141 resultados para Bloomington-Normal Park District (Proposed)
Resumo:
Abstract Background: More than 50% of the patients with heart failure have normal ejection fraction (HFNEF). Iodine-123 metaiodobenzylguanidine (123I-MIBG) scintigraphy and cardiopulmonary exercise test (CPET) are prognostic markers in HFNEF. Nebivolol is a beta-blocker with vasodilating properties. Objectives: To evaluate the impact of nebivolol therapy on CPET and123I-MIBG scintigraphic parameters in patients with HFNEF. Methods: Twenty-five patients underwent 123I-MIBG scintigraphy to determine the washout rate and early and late heart-to-mediastinum ratios. During the CPET, we analyzed the systolic blood pressure (SBP) response, heart rate (HR) during effort and recovery (HRR), and oxygen uptake (VO2). After the initial evaluation, we divided our cohort into control and intervention groups. We then started nebivolol and repeated the tests after 3 months. Results: After treatment, the intervention group showed improvement in rest SBP (149 mmHg [143.5-171 mmHg] versus 135 mmHg [125-151 mmHg, p = 0.016]), rest HR (78 bpm [65.5-84 bpm] versus 64.5 bpm [57.5-75.5 bpm, p = 0.028]), peak SBP (235 mmHg [216.5-249 mmHg] versus 198 mmHg [191-220.5 mmHg], p = 0.001), peak HR (124.5 bpm [115-142 bpm] versus 115 bpm [103.7-124 bpm], p= 0.043), HRR on the 1st minute (6.5 bpm [4.75-12.75 bpm] versus 14.5 bpm [6.7-22 bpm], p = 0.025) and HRR on the 2nd minute (15.5 bpm [13-21.75 bpm] versus 23.5 bpm [16-31.7 bpm], p = 0.005), but no change in peak VO2 and 123I-MIBG scintigraphic parameters. Conclusion: Despite a better control in SBP, HR during rest and exercise, and improvement in HRR, nebivolol failed to show a positive effect on peak VO2 and 123I-MIBG scintigraphic parameters. The lack of effect on adrenergic activity may be the cause of the lack of effect on functional capacity.
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The main object of the present paper consists in giving formulas and methods which enable us to determine the minimum number of repetitions or of individuals necessary to garantee some extent the success of an experiment. The theoretical basis of all processes consists essentially in the following. Knowing the frequency of the desired p and of the non desired ovents q we may calculate the frequency of all possi- ble combinations, to be expected in n repetitions, by expanding the binomium (p-+q)n. Determining which of these combinations we want to avoid we calculate their total frequency, selecting the value of the exponent n of the binomium in such a way that this total frequency is equal or smaller than the accepted limit of precision n/pª{ 1/n1 (q/p)n + 1/(n-1)| (q/p)n-1 + 1/ 2!(n-2)| (q/p)n-2 + 1/3(n-3) (q/p)n-3... < Plim - -(1b) There does not exist an absolute limit of precision since its value depends not only upon psychological factors in our judgement, but is at the same sime a function of the number of repetitions For this reasen y have proposed (1,56) two relative values, one equal to 1-5n as the lowest value of probability and the other equal to 1-10n as the highest value of improbability, leaving between them what may be called the "region of doubt However these formulas cannot be applied in our case since this number n is just the unknown quantity. Thus we have to use, instead of the more exact values of these two formulas, the conventional limits of P.lim equal to 0,05 (Precision 5%), equal to 0,01 (Precision 1%, and to 0,001 (Precision P, 1%). The binominal formula as explained above (cf. formula 1, pg. 85), however is of rather limited applicability owing to the excessive calculus necessary, and we have thus to procure approximations as substitutes. We may use, without loss of precision, the following approximations: a) The normal or Gaussean distribution when the expected frequency p has any value between 0,1 and 0,9, and when n is at least superior to ten. b) The Poisson distribution when the expected frequecy p is smaller than 0,1. Tables V to VII show for some special cases that these approximations are very satisfactory. The praticai solution of the following problems, stated in the introduction can now be given: A) What is the minimum number of repititions necessary in order to avoid that any one of a treatments, varieties etc. may be accidentally always the best, on the best and second best, or the first, second, and third best or finally one of the n beat treatments, varieties etc. Using the first term of the binomium, we have the following equation for n: n = log Riim / log (m:) = log Riim / log.m - log a --------------(5) B) What is the minimun number of individuals necessary in 01der that a ceratin type, expected with the frequency p, may appaer at least in one, two, three or a=m+1 individuals. 1) For p between 0,1 and 0,9 and using the Gaussean approximation we have: on - ó. p (1-p) n - a -1.m b= δ. 1-p /p e c = m/p } -------------------(7) n = b + b² + 4 c/ 2 n´ = 1/p n cor = n + n' ---------- (8) We have to use the correction n' when p has a value between 0,25 and 0,75. The greek letters delta represents in the present esse the unilateral limits of the Gaussean distribution for the three conventional limits of precision : 1,64; 2,33; and 3,09 respectively. h we are only interested in having at least one individual, and m becomes equal to zero, the formula reduces to : c= m/p o para a = 1 a = { b + b²}² = b² = δ2 1- p /p }-----------------(9) n = 1/p n (cor) = n + n´ 2) If p is smaller than 0,1 we may use table 1 in order to find the mean m of a Poisson distribution and determine. n = m: p C) Which is the minimun number of individuals necessary for distinguishing two frequencies p1 and p2? 1) When pl and p2 are values between 0,1 and 0,9 we have: n = { δ p1 ( 1-pi) + p2) / p2 (1 - p2) n= 1/p1-p2 }------------ (13) n (cor) We have again to use the unilateral limits of the Gaussean distribution. The correction n' should be used if at least one of the valors pl or p2 has a value between 0,25 and 0,75. A more complicated formula may be used in cases where whe want to increase the precision : n (p1 - p2) δ { p1 (1- p2 ) / n= m δ = δ p1 ( 1 - p1) + p2 ( 1 - p2) c= m / p1 - p2 n = { b2 + 4 4 c }2 }--------- (14) n = 1/ p1 - p2 2) When both pl and p2 are smaller than 0,1 we determine the quocient (pl-r-p2) and procure the corresponding number m2 of a Poisson distribution in table 2. The value n is found by the equation : n = mg /p2 ------------- (15) D) What is the minimun number necessary for distinguishing three or more frequencies, p2 p1 p3. If the frequecies pl p2 p3 are values between 0,1 e 0,9 we have to solve the individual equations and sue the higest value of n thus determined : n 1.2 = {δ p1 (1 - p1) / p1 - p2 }² = Fiim n 1.2 = { δ p1 ( 1 - p1) + p1 ( 1 - p1) }² } -- (16) Delta represents now the bilateral limits of the : Gaussean distrioution : 1,96-2,58-3,29. 2) No table was prepared for the relatively rare cases of a comparison of threes or more frequencies below 0,1 and in such cases extremely high numbers would be required. E) A process is given which serves to solve two problemr of informatory nature : a) if a special type appears in n individuals with a frequency p(obs), what may be the corresponding ideal value of p(esp), or; b) if we study samples of n in diviuals and expect a certain type with a frequency p(esp) what may be the extreme limits of p(obs) in individual farmlies ? I.) If we are dealing with values between 0,1 and 0,9 we may use table 3. To solve the first question we select the respective horizontal line for p(obs) and determine which column corresponds to our value of n and find the respective value of p(esp) by interpolating between columns. In order to solve the second problem we start with the respective column for p(esp) and find the horizontal line for the given value of n either diretly or by approximation and by interpolation. 2) For frequencies smaller than 0,1 we have to use table 4 and transform the fractions p(esp) and p(obs) in numbers of Poisson series by multiplication with n. Tn order to solve the first broblem, we verify in which line the lower Poisson limit is equal to m(obs) and transform the corresponding value of m into frequecy p(esp) by dividing through n. The observed frequency may thus be a chance deviate of any value between 0,0... and the values given by dividing the value of m in the table by n. In the second case we transform first the expectation p(esp) into a value of m and procure in the horizontal line, corresponding to m(esp) the extreme values om m which than must be transformed, by dividing through n into values of p(obs). F) Partial and progressive tests may be recomended in all cases where there is lack of material or where the loss of time is less importent than the cost of large scale experiments since in many cases the minimun number necessary to garantee the results within the limits of precision is rather large. One should not forget that the minimun number really represents at the same time a maximun number, necessary only if one takes into consideration essentially the disfavorable variations, but smaller numbers may frequently already satisfactory results. For instance, by definition, we know that a frequecy of p means that we expect one individual in every total o(f1-p). If there were no chance variations, this number (1- p) will be suficient. and if there were favorable variations a smaller number still may yield one individual of the desired type. r.nus trusting to luck, one may start the experiment with numbers, smaller than the minimun calculated according to the formulas given above, and increase the total untill the desired result is obtained and this may well b ebefore the "minimum number" is reached. Some concrete examples of this partial or progressive procedure are given from our genetical experiments with maize.
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O presente trabalho tem por objetivo extrair e determinar diversos íons, como o alumínio, hidrogênio, cálcio e magnésio que se acham ligados aos colóides do solo por eletrovalência, em alguns solos do Município de Piracicaba. Além disso, constitui também finalidade dêste trabalho relacionar as diversas características dos solos estudados a fim de esclarecer vários aspectos considerados importantes na química do solo. Trinta e seis amostras de solos, correspondentes aos horizontes superficiais e subsuperficiais de dez séries do citado Município, foram submetidas à extração com solução 1 N de KCl e no extrato foram determinados os cátions já mencionados, além de determinar o pH em suspensão da solução 1 N em KCl. Nas mesmas amostras foram determinados: pH em suspensão aquosa, carbono total, cálcio, magnésio e potássio extraídos com solução 0,05 N de HNO3 e hidrogênio extraído com solução 1 N de acetato de cálcio com pH = 7,0. Os dados obtidos permitem concluir que a carga negativa permanente dos colóides dos solos estudados é muito baixa e que uma fração elevada da mesma é neutralizada pelo alumínio, em muitas das amostras analisadas. Verificou-se, também, que o teor de alumínio trocável correlaciona-se tanto com o pH determinado em suspensão aquosa, como com o determinado em suspensão de solução 1 N de CKl e com o hidrogênio, extraído com solução de acetato de cálcio 1 N com pH = 7,0. A porcentagem de saturação de bases, calculada em função da carga permanente e a calculada em função da extração das bases com solução de HNO3 0,05 N e da extração do hidrogênio com solução de acetato de cálcio 1N, pH = 7,0, correlacionam-se com o pH do solo. Finalmente, constatou-se que o teor de cálcio mais magnésio extraído com solução 1 N de KCl é equivalente ao extraído com solução 0,05 N de HNO3, indicando que, provàvelmente, os solos estudados não apresentam minerais silicatados ou carbonatados dos mencionados cátions.
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Fez-se a aplicação de giberelinas (50 e 100 ppm) e de clorofenoxipropionamida (250, 500 e 1000 ppm) sobre figos em vários estádios de desenvolvimento, de plantas podadas em dezembro, visando-se à produção de figos fora da época normal. Os resultados demostraram que as giberelinas a 50 ppm provocaram alongamento no comprimento dos figos. O tratamento com clorofenoxipropionamida (Fruitone CPA) a 1000 ppm resultou em frutos mais pesados, porém, estes valores não diferiram estatisticamente daqueles do tratamento controle. O peso médio dos figos foi de 50,0 gramas, para as primeiras oito semanas de colheita, período considerado no experimento.
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Conduziu-se um experimento na Fazenda Canchim, em São Carlos, SP, para se verificar se determinados componentes do sangue de bovinos jovens refletiriam diferentes estados nutricionais. 0 delineamento estatístico foi o de blocos casualizados. Empregaram - se 36 bovinos canchim desmamados, inteiros, em regime de pasto exclusivo (T1), ou confinados, recebendo feno de soja e rolão de milho (T2), torta de algodão e cana-de-açúcar (T3), ou ração completa (T4), de março a setembro de 1973, e em seguida somente pasto, até março de 1974. No período de confinamento, as pesagens e coletas de sangue foram a cada 2 semanas, passando para 4no período seguinte. Embora os tratamentos houvessem proporcionado diferentes níveis de consumo, de ganho de peso e de conversão, não houve variação correspondente nos diversos componentes de sangue analisados, talvez porque os intervalos de coleta e de pesagens deveriam ter sido mais curtos, para que se relacionassem melhor, pois os primeiros dados corresponderam às médias diárias do intervalo entre pesagens, enquanto que as dosagens correspondiam a uma única determinação do dia da coleta. A utilização de "kits" para análise do sangue comprovou-se plenamente satisfatória, mais simples e rápida em relação ao sistema convencional. Foram assumidos como normais os níveis médios para os seguintes parâmetros do sangue: uréia, 11,1 a 16,1 mg;proteínas totais, 5,92 a 6,32 g; fósforo, 6,24 a 7,11 mg; Ca, 11,01 a 12,66 mg; e hemoglobina, 10,14 a 10,55 g por decilitro.
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We analysed species abundance and composition during one year of sampling at Itapuã State Park, a conservation unit in the State of Rio Grande do Sul, southern Brazil. Samples were collected monthly from May 2003 to April 2004 along a 4 km forest trail divided in three transects along the slopes of a small hill. Terrestrial isopods were hand searched by three people for 40 minutes at two sampling sites along each transect, summing 240 minutes of sampling effort per transect per month. Six species distributed in six families were found. The collector curve stabilised when half the samples were taken, demonstrating sampling sufficiency: analytical estimates did not predict more species to be found in the trail. Atlantoscia floridana (van Name, 1940) was dominant in all transects. Abundance varied along the year with a summer and a winter peak, but peaks were not consistent among transects. The first part of the trail, used for ecotourism, was less diverse, had less species (4 as compared to 6 in the other transects), and was thus also less similar in composition.
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The Ilha Grande National Park, Paraná, Brazil, is located in the Upper Paraná River and has characteristics typical of a floodplains. This protected area includes lagoons connected and disconnected to the Paraná River, although the latter also connect during periods of high water level, thus composing a heterogeneous group of lacustrine environments. The enormous potential the flora and fauna diversities are still little known to the region, as can be seen through benthic invertebrates, inclunding bivalves mollusks. The granulometric composition of these floodplain lagoons was formed mainly by mud and very fine sand. Furthermore, organic matter composition was predominantly of fine particulate. The other abiotic factors differed from lagoons located within the island of the park to those located in the left margin of Paraná River. The results demonstrated the importance of abiotic factors such as the physical composition of granulometric texture, organic matter and macrophyte banks, to the establishment of bivalves in these floodplain lagoons. We recorded bivalves of Pisidium (native), Diplodon (native), and Corbicula (invasive). The highest values of Diplodon sp. density were observed at São João/C lake, for Pisidium sterkianum (Pilsbry, 1897) at São João/M lake, and to Jatobá/C lagoon with high density of invasive species Corbicula fluminea (Müller, 1774). This study to obtain conduct the first records of freshwater bivalves in floodplains lagoon in the Ilha Grande National Park, and provides contributions to better understanding the ecology of these mollusks. The recording of native species in the region of Upper Paraná River floodplain after a lomg period without new records, demonstrated the importance of protecting the lagoons of the Ilha Grande National Park as they can be a possible refuge to some species of native freshwater bivalves.
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Some bat species are able to adapt to urban areas, where they find food and roosts. Despite the high number of parks in Brazilian cities, they did not yet raise the interest of most zoologists, except for some surveys of birds and butterflies. The objectives of the present study were: (i) to inventory the bat species of Quinta da Boa Vista (QBV), a large (25 ha) urban park centrally located in densely populated Rio de Janeiro, which is Brazil's second largest metropolis; (ii) to compare the species richness observed in roosts with the richness recorded through mist netting in flight routes and near fruiting fig trees; and (iii) to analyze recaptures of bats marked in this park and recaptured in other sites and vice-versa. Sampling totaled 104 sampling nights resulting in 3,256 captures (including 133 recaptures) between April 1989 and December 2004. We also sampled roosts and received some specimens from park visitors and city workers. We documented 21 bat species, predominantly large frugivores. The number of expected species for this park was 24.0 ± 4.6, and the total sampled represented 87.5% of the expected. The recapture of bats marked in surrounding forest fragments and in QBV shows the importance of urban parks for the maintenance of bat diversity. Inspection of roosts produced two species that had not been captured with other methods. Sampling near fruiting fig trees did not differ in terms of richness from sampling carried out far from these trees or during their non-fruiting periods.
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1. In a series of 21 normal cases we found for fatty acids per 100 cc. of plasma an average of 332 mgm., being 314 mgm. for the male sex and 350 mgm. for the female sex. 2.- For lecithin, in four normal cases we found per 100 cc. of plasma 182 mgm. estimated by the contents is phosphorus which ranged from 6.12 to 9.0 mgrs. 3.- Cholesterol in 20 normal cases showed 172 mgm. per 100 cc. of plasma. The averages were 151 mgm. for men and 194 mgm. for women. 4.- The readings of the fractions were 2.01 for the ratio fatty acids divided by lecithins 0.90 for lecithin divided by cholesterol and 1.93 for fatty acids divided by cholesterol. 5.- On comparing the results obtained by us with those reported in foreign literature an absolute conformity is noted chiefly with the values supplied by Bloor and Horiuchi for the ratios among the various lipoid fractions. The average for Cholesterol is comparable with that obtained by Myers but is slightly under that of Bloor's. The lecithin contents found by us did not reach such high values as those supplied by foreign authors.
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1.) - Woodward-Fry's and Okuda-Hess technics were employed in the determination of blood glutathione in normal healthy adults of both sexes. 2.) - It was found more accurately results with the technic of Woodward and Fry than of any others for the dosage of G. S. H. of blood. 3.) - When the process of Okuda-Hess is modified by the use of an intern indicator (starch) the readings of the end-point are much more easy and therefore the results more exacts. 4.) - The averages of the data obtained for normal blood by the technic of Woodward and Fry were for men per hundred cubic cent. 27 mgrs (G.S.H); 6.6 mgrs. (G.S.S) and 33.6 mges. (G. T) and for women: 28.4 mgrs. (G.S.H), 7.8 mgrs. (G.S.S) and 36,2 mgrs. (G.T). 5.) - Autoxidation in the blood filtrate is only apreciated after 24 hs. In the first eight hours autoxidation is never observed. 6.) - The increase of glutathione in hyperglobulia is a function of the amount of red corpuscles. In acrocyanosis arterial blood is richest in these component than venous blood and this fact is in accordance with the observation of Blanchetière, Mélon and Binet for the experimental asphyxia of dogs.
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A critical study of three methods for the determination of lactic acid (EDWARDS, MENDEL & GOLDSCHEIDER, MILLER & MUNTZ) is presented and some modifications are proposed. It was shown t hat more accurate results could be obtained with Edward's technic when an Iena glass filter is connected with the absorption tube. Before the dropping of the permanganate solution it is necessary to pass a current of air through the reaction flask to avoid the oxidation of the non-lactic acid substances which interfere with the reaction. The absorption tube must be maintained at 18°C during the destillation and the titration of the bisulphite binding aldehyde at 4°C. When the sample contains more than 5 mg it is useful to work with greater quantities of the bisulphite. More permanganate is consumed when the lactic acid concentration is higher. The sensivity of the method permits the titration of 0.04 mg to 5 mg of lactic acid in the sample. The calculated error of the method gave 0.018 % and the normal values for blood determined in 20 human cases averaged 10.30 mg per 100 ml (Table VI). MENDEL and GOLDSCHEIDER'S method was modified in the following details: Somogyis deproteinization was performed instead metaphosphoric acid as in the original method; to avoid the evaporation of the acetic aldehyde during the heating time with sulfuric acid a special glass stopped tube is proposed (Fig. 2). The reaction with sulfuric acid and veratrol is performed in an ice bath. Blood proteins precipitants were tried and Somogyi's lattest tecnic showed better results (Table V). Colorimetric readings were done in the PULFRICH photometer using filter S 53 and a 10 mm cup. The method is accurate within an error of 0.23 % and samples of 5 to 70 microg. could be easily determined. Normal values for human blood averaged 10.78 mg per 100 ml. More accurate results were obtained with the technic of MILLER & MUNTZ. Slight modifications were introduced: deproteinization with copper sulfate and sodium tungstate; satured p-hydroxydiphenyl solution according to KOENEMANN which is stable for 5 months when stored in the ice-box. Using the PULFRICH step-photometer the error is 0.17% with samples varying from 0.1 to 10 microg. of lactic acid. The filter employed was S 57 with the 5 mm cup. The method was adapted to 0.1 ml of blood. Normal values for human blood gave an average of 10.58 mg per 100 ml.
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In this paper, preliminary to a series of investigations that the A. has the purpose to make about the influence of climatic factors particularly upon the prevalence of the most important acute infectious diseases in Brazil, he raises the question whether such factors do affect in this country the total death rates, as it is reasonable to suppose, according to what has been observed in temperate zones of northern and southern hemispheres. The inclusion of absolute humidity among other climatic factors to be dealt with seems justifiable according to Rogers and Stallybrass. Owing to scarcety of reliable data the A. was obliged to limit to a five-years period (1940-1944) the complete proposed investigation, which includes seven of the most important cities, scattered throughout the brazilian territory, from north to south - Belém, recife, Salvador, Rio, S. Paulo, Curitiba and Porto Alegre. Reference is made to their normal climatic conditions and monthly death-rates variations with their mean values and standard deviations. In a first part dealing with seasonal variations only for purposes of comparison, he points out that in there tropical cities of Brazil, without very clear seasonal differentiation, the curve of general mortality reached its highest point in austral autumn season and the remaining four (including Rio near the tropic) in the spring, with the exception of Curitiba, where the peak coincided with the summer season. He shows how such important causes of deaths, as diarrheas, common respiratory diseases and tuberculosis, whose seasonal distribution for each one of the seven cities is referred, may explain such seasonal variations. On a second part, a study is made of the general mortality distribution by four-months periods selected in accordance respectively with the highest or lowest values of rainfall and of mean temperature and humidity during period 1940-1944. Finally he compares the monthly waves of such climatic factors and the corresponding waves of total death - rates and finds through correlation coefficients 17 significant values with respect to their standard errors. Variations in the death - rates seemed to be perhaps more closely and uniformly associated with variations of mean humidity, as is indicated by coefficients ranging from + 0.3 to 0.6.
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A new tick, Amblyomma parkeri, n. sp., is described as a parasite of Coendu sp. from S. Paulo, Brazil. Female holotype, nymph and larva are described (Figs. 2 e 3). The n. sp. differs completly from Koch's species Amblyomma longirostre, the common parasite of the Erethizotidae. Standard data for measures of the female dorsal scutum ixodidae are proposed as follows (fig. 1): PA = Antero-posterior; PB = Postero-basal; PM = Postero-median; TT = Transversal; OO = Inter-ocular; OT= Occulo-transversal; SS = Inter-scapular; CC = Cervical; PT = Postero-transversal; ST = Scapulo-transversal; NPT = Normal to the postero-transversal; NST = Normal to the scapulo-transversal. In the female holotype the standard data are as follows: PA = 2.00 mm; PB = 2.26 mm; PM = 1.10 mm; TT = 2.20 mm; OO = 2.26 mm; SS = 0,84 mm; CC = 0.63 mm; SC = 0.12 mm; NPT = 0.20mm; STN = 0.1 mm. Peritrema 0.80 x 0.42 mm with a narrow postero-internal angle and a large, elongated macula. Coxa I with two short spines and all other coxae with only one shorter spine, shortest in coxa IV. Hypostoma spatulated with formula 3/3. Gnathosoma 1.42 mm long and basis 0.63 mm long by 0.84 greatest wide. Palpi with smoth external surface, 1.00 mm long. Type lot No. 4458 from Cotia, S. Paulo, Brazil; in the acarological collection of the Escola Paulista de Medicina, S. Paulo. Ixodes didelphidis, n. sp., differing from Ixodes loricatus Neumann by the shape of the peritremata (figs. 4 a 5) of the male and female and by the number of the punctations in this organ is described form Didelphidae, Muridae and Cavidae. Twenty eight lots were obtained from Anápolis, Goiás, Brasil, where I. loricatus is subtituded by the n. sp. under description. Comparison with NEUMANN'S types of I. loricatus was possible through the courtesy of Prof. A. BRIZARD from Toulouse, who kindly loaned NEUMANN'S material. Female cotypes N° 40 and male allotype N° 531 in the Collection of Ixodidae of the Oswaldo Cruz Institute.
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Total urinary neutral 17-steroids were determined in normal and in castrated horses. One liter of a 15-26 hours urine collection was hydrolysed by refluxing with 10% HC1 (v/v) for ten minutes and extracted with peroxyde-free ethyl ether. The extract was purified by washing with saturated NaHCO³ and KOH solutions. One half of the crude neutral fraction was fractionated with Girard's "T" reagent . The Zimmermann reaction was performed both in the ketonic and in the crude neutral extracts, using alcoholic 2.5N KOH and a 60 minutes period for the colour development in the dark. Optical density measuments were made in a grating Coleman Universal Spectrophotometer at 420 mµ and 520mµ; for the crude neutral fraction a colour correction equation was applied. The aliquot fraction used for colorimety was adjusted for keeping optical density measurements within the range 0.2 to 0.7. Androsterone (mp. 184-184.5°C) with an absorption maximum at 290.5 mµ (Beckman Model DU Spectrophotometer) was used as a reference standard. Table I, ilustrates the results obtained. At the 0.05 probability level there is a significant difference among castrated and normal group means (Fischer's "t" test.) when were used the data obtained from the ketonic fractions; in spite of the use of a colour correction applied for inespecific chromogens, the same results could not be obtained with the crude neutral fractions, Since Girard's reagent fractionation is generaly accepted as the best method for correcting the inespecific chromogen interference in the determination of the 17-ketosteroids by the Zimmermann reaction, we emphasize the value of the results obtained with the ketonic fractions. From these results it appears, as occurs in others mammals, that castrated horses show a lower level of urinary 17-ketosteroids excretion than the normal horses. The significance of the horse testis contribution for the neutral urinary steroid metabolites is discussed. Since horse urine has a low androgenic activity, the fractionation of the neutral 17-ketosteroids must be studied more accurately.