996 resultados para cavity QED


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Cephalobium bidentatum sp. nov., parasitizing nymphs of Gryllodes laplatae Sauss (Orthoptera, Gryllidae) from Argentina, is described and illustrated. It is distinguished from other members of the genus Cephalobium COBB, 1920, by having the buccal cavity very sclerotized with two hook-shaped teeth, vagina short and muscular, male has two spicules with hook-shaped tips, and by the distribution pattern of the postanal papillae: one pair under the anus, three pairs between the anus and the tail, and two pairs at the base of the tail appendage.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The population growth of Simpulopsis ovata (Sowerby, 1822) from the Centro de Pesquisas e Conservação da Natureza - Pró-Mata, São Francisco de Paula, Rio Grande do Sul, Brazil, was studied along eleven months of 1996. Two discontinuous age classes were identified. The first one, with a monthly growth rate of 1.55 mm, was reproductively mature during April and May. The second one appeared after the previous group and had a monthly growth rate of 0.44 mm. The fact that no adults from the two age classes were found together is a characteristic of a semelparous species. New insights about its shell, pallial cavity and reproductive system are given. This is the first record of S. ovata for the State of Rio Grande do Sul.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Macrocyclis peruvianus (Lamarck, 1822) is a large terrestrial snail which is endemic in Chile. A detailed description of its shell structure, jaw, radula, palial cavity and reproductive system is presented here for the first time.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The only breeding record of Spartonoica maluroides (d'Orbigny & Lafresnaye, 1837) for Brazil is based on the observation of a fledgling in southern Rio Grande do Sul in January 1976. On 7 December 2005 we discovered a nest containing three nestlings at the southeastern end of Lagoa Pequena, municipality of Pelotas, Rio Grande do Sul. The nest was concealed at the base of a cavity in a Spartina densiflora (Poaceae) tussock located at the edge of a saltmarsh. The nest was built of fine pieces of dead Scirpus olneyi (Cyperaceae) and S. densiflora leaves firmly interlaced to the internal leaves of the tussock. Live leaves of S. densiflora lining the cavity comprised a substantial part of the nest's architecture, forming most of its upper lateral walls and roof. The lower section was more elaborate, resembling a deep cup and forming a distinct incubation chamber. Adults reached the nest's interior through an irregular apical opening amidst the leaves. The nest was 244 mm high and 140 mm wide. The incubation chamber had an external diameter of 138.5 mm, an internal diameter of 79.4 mm and was 86 mm deep. It was lined with fine leaves and white plant fibers. Nestlings were five to six days old. A total of 107 neossoptiles restricted to the capital, spinal and alar tracts were recorded in one nestling. The distribution of neossoptiles in the ocular region of S. maluroides forms a distinct pattern which can be typical of Furnariidae and related families. Two adults attended the nest, bringing small insects to the nestlings and removing fecal sacs. We recorded at least 74 visits to the nest during a ca. 6 h period during an afternoon. The average number of visits per hour was 12.8 ± 1.3. An adult bird spent on average 0.7 ± 0.56 minutes inside the nest attending nestlings. The nest remained unattended on average for 3.61 ± 3.13 minutes. The hour of the day had no influence on the amount of time spent by an adult in the nest or away from it. We returned to the area on 15 December 2005 and found the nest abandoned. Observations confirm that S. maluroides is a resident breeder in southern Brazil and that the saltmarshes of the Lagoa do Patos estuary are an important year-round habitat for the species. A nestling and the nest were collected to document the record.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The A. studies critically the literature on D. caudispina (Molin, 1858) and concludes that it is a good species, differing from D. gracilis (Rudolphi, 1809), principally, by the longer spicule. This conclusion is confirmed by the study of material collected by d'Almeida in the abdominal cavity of one specimen of Ateles paniscus (L.), of the State of Pará, Brazil. In contradiction to Stiles & Hassall's opinion the A. indicates this monkey for host-type of the Molin's species. A synonymic list and a redescription of D. caudispina are given.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The authors described the experiments with Penicillin Merck-Sodium Salt n. 135 in order to verify the curative action on the experimental disesase of the guineapig. I - They found that small doses, of 1,600 units, Oxford, when inoculated during the first 24 or 48 hours of the appearance of the feverish reaction are impotent to modify the course of the disease, whether in the thermic curve, or the testicular or esplenomegalic manifestations. II - Penicillin, when used in larger doses, from 25,000 to 30,000 units, Oxford, in 24 hours through peritonial cavity is capable of normalising the temperature, modifying to a certain degree the virulence of the virus in guinea-pigs. III - In large doses, even when injected later, it causes the temperature to fall, in all animals, attenuating the viceral manifestations. IV - Direct contact of Penicillin with the virus, during many hours, cause it to loose its virulence.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In two experiments, 8 Hamsters inoculated with material from yaws lesions (Treponema pertenue), developed skin lesions considered specific by their clinical and histopathological aspects and by the presence of treponemae. These lesions appeared on the scrotumm, testicle, prepuce, anus, tail, muzzle, back and hinders paws (palm surface). In the internal organs no treponemae were found in direct examinations and inoculation of brain, spleen and lymph node. The incubation period was of 35 days for the testicle, 55 days for the scrotum and 107 days for peritoneal cavity inoculation. Positive sub-inoculations were obtained. The serum reactions (Qasserman's and Kahn's) were negative in all 5 tested Hamsters. Out of 4 normal females matched to infected males two developed nasal lesions resulting from direct contact. Apparently the genital lesions hindered copulation. Hamsters are very well suited for an experimental study of yaws.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

We had the opportunity to study 6 cases of the congenital form of toxoplasmosis, found in a series of 1200 necropsies of fetuses and newborn babies, realized at 3 different hospitals in Rio de Janeiro, Brazil. Among the 6 cases, 4 were premature babies liveborn at the 6th-8th gestational month and 2 were stillborn (1 premature and 1 at term). In all those cases, the diagnosis was based in the detection of the parasite in tissues and in one case it was even isolated the Toxoplasma from the necrotic material found in the cranial cavity. This strain of Toxoplasma, pathogenic to pigeons, to guinea pigs and to mice, is preserved by successive transfers in mice. Some facts observed in those cases present an interest not only strictly anatomic but also have certain value for the better acknowlegment of the disease. First, we want to call the attention to the presence of a sudden high fever, during or just before pregnancy in the 4 cases in which the maternal anamnesis was perfectly studied; this fever that was preceded by a normal beginning of pregnancy, had relatively rapid remission, but in 2 cases was immediately followed by uterine bleeding and premature delivery, although the puerperium had been apparently normal. It is known that are normal the subsequent children of the mothers that delivered a baby with toxoplasmosis and that several women have normal babies before the toxoplasmotic one. We believe that the fever observed in our cases could be indicative of the beginning of maternal infection and those are the reasons why we emphasize the need of careful anamnesis, specially in the cases actually diagnosed as inapparent infection. Another fact to notice is that in 5 of our cases the event premature delivery happened always between the 6th and the 8th months of pregnancy, and the only term fetus was delivered in advanced stage of maceration. The above mentioned facts could agree with the opinion of FRENKEL (1949), when he declared that "primary infection of the pregnant mother appears more likely to be the commoner mode of fetal toxoplasmic infection", but they would disagree with WEINMAN (1952) who believes that the transmission of Toxoplasma to the fetus is more frequent through a pregnant woman with chronic disease and who says "that infection contracted during pregnancy may and probably does happen from time to time"...Still in connection with the transmission of toxoplasmosis, we want to note the verification of inflammatory lesions in the placental villi and in the umbilical cord in 3 of the 4 cases in which such organs were examined at the microscope. In the case n. 1, we found several pseudocysts of Toxoplasma in the placenta, and the fibroblasts of Wharton's jelly were particularly rich in isolated forms and in colonies of Toxoplasma; the easy multiplication of the parasite in that tissue calls the attention and even suggests its utilisation for Toxoplasma's cultivation. The confirmation of Toxoplasma in human placenta was made only recently by CRISTEN et al. (1951) and by NEGHME et al. (1952), in Chile; it is not frequent in the literature, what gives some value to our present verification. Another observation was that provided by the case n. 6. This baby, a premature one of the 6th month, was 14 days old and-died with signs of respiratory disease, the causa mortis have been pneumonia. At the necropsy, we found no gross change that suggested toxoplasmosis, except the presence of some small necrotic focuses in the cerebral nervous substance around the ventricles. As a matter of fact, there was no enlargement of spleen or liver and neither leptomeningitis nor hydrocephalus. Such focuses were attributed to possible anoxia and in fact they are extremely similar to anoxial softenings, even when they are examined at the microscope; its structure composed of a central necrotic zone, surrounded by proliferated neuroglia and by a variable deposit of calcium salts, closely simulated the anoxial softenings, when the microscopical examination is based in the common histological preparations (hematoxilin-eosin, etc.). But when we examine preparations by the Giemsa or by the periodic acid-Schiff methods, we will note the presence of Toxoplasma, with its typical aspect or a little changed by degeneration. When we describe this observation, we wish to evidence the need of the search of Toxoplasma and closed parasites, in the cases of supposed pure anoxial softenings of nervous substance, in children. The frequency with which the congenital toxoplasmosis was anatomically verified should be emphasized, although the disease had not been clinically suspected, and it should be borne in mind that the second case of toxoplasmosis reported in the world was observed in Brazil by MAGARINOS TORRES; this case was the first to be described of the generalized congenital form of the infection, i. e. with myocardial lesions and parasites in skeletal muscles and skin.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In 1939, Mangabeira obtained, under laboratory conditions, the development of eggs of Phlebotomus brasiliensis Costa Lima, 1932, collected at Lassance (typical locality), Minas Gerais, Brasil. He then studied the female and immature stages of this Phlebotomus. The results of these observations plus some more recent data on the male, geographical distribution and bionomics are presented. Morphologically it is closest to Phlebotomus runoides. However, the male Phlebotomus brasiliensis differs from all other Phlebotomus because of its very long spicules, similar to those of Brumptomyia. The female differs by its longer ducts, and by possessing only four horizontal teeth in the buccal cavity, whereas P. runoides has approximately 12 teeth. The pupae of P. brasiliensis is characterized by its two pre-alar setae, which are very simple and small and by the abdominal setae, which are not planted on a protruding tubercle. The fourth stage larvae main characteristics are very thin antennae, inserted on a protruding tuberculum, and slightly brush-like hind frontal setae. P. brasiliensis is here reported, for the first time, for the State of Bahia (Cachoeira, Pojuca and Salvador). The species has almost always been found in armadillo burrows. In the State of Bahia it is more frequent during the dry season. Under laboratory conditions, the female lays about 53 eggs.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The Embioptera are rather generalized insects whose internal anatomy is simple and not subject to great modifications. For this reason these insects form an ideal group for elementary anatomical and histological studies (fig. 2). The digestive tract is a long, simple tube without convolutions or diverticulae from the buccal cavity to the rectum. The buccal structures are of the chewing type. The oesophagus and ingluvia are differentiated only by slight dilation of their walls. In nymphs and females the proventriculus is very distinct due to folds which flatten as the structure becomes packed with food. The enteron is the largest in such forms and in both sexes limited caudally by the Malpighian tubules. The proctodeus has six large rectal papillae. The nervous system is complete with only the fifth abdominal segment lacking a ganglion in the metathorax includes the ganglion of the first abdominal segment. The brain exhibits very clear structure in histological sections. The tracheal system includes two pairs of thoracic spiracles and eight abdominal pairs. Only th metathoracic spiracle has an air expiration function; all others serve for inspiration. Various structures in the spiracles protect the atrium. The circulatory system includes a long, simple dorsal vessel which extends forward from the ninth abdominal segment into the cranium. It opens anteriorly near the circumoesophageal connectives. The dorsal vessel has a pair of ostia and valves corresponding to each abdominal and thoracic segment. It lacks the diverticulae or folds commonly found in more highly evolved insects. The excretory system is represented by Malphighian tubules, pericardial cells, and fat-body. The number and disposition of Malpighian tubules is variable within the order. The pericardial cells are localized around the entire dorsal vessel up to the opening of the aorta in the head. The fat-bodies form compact layers in the dorsal and ventral regions of the body. In males they are more developed in the abdominal region. The mandibles, maxillae, and salivary glands are of a simple type with very few cytological modifications. Only the salivary glands which extend into the mesothoracic region show appreciable specialization. The reproductive system is bi-sixual and shows considerable sexual dimorphism. Males have five pair of testes with a metameric disposition, two distinct ducts, two epidymis, and the ejaculatory organs. The accessory glands vary in number and size and open in the anterior portion of the ejaculatory duct. The female reproductive organs are of the panoistic type. The system includes five pairs of ovarioles, two long paired oviducts a small, unpaired oviduct and the spermatheca which opens in the vagina. Reproduction usually involves a union of male and female gametes, and eggs are usually laid in clusters attached to a substrate.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Mice treated with hyperchlorinated water (50 ppm of chlorine) and control mice, drinking tap water (1-3 ppm of chlorine) were inoculated with 2.5 x 10 [raised to the power of 6] sarcoma 180 cells, by intraperitoneal route. Tumor evolution was measured by enumeration of tumor cells in peritoneal cavity and by evaluation of weight gain at different time intervals after tumor implantation. In mice treated with excessive amounts of chlorine there was enhancement of tumor growth demonstrated by: (a) shorter incubation period and increased weight gain (ascites formation) after tumor implantation; (b) increased number of tumor cells in the peritoneal cavity 2, 3 and 4 days after tumor challenge. The number of peritoneal cells exsudated after tumor implantation was lower in mice treated with hyperchlorinated water than in controls. The tumor enhancement observed after excessive chlorine ingestion would be due to: (a) reduction of the number of peritoneal macrophages that migrate to the peritoneal cavity and (b) reduction of the tumoricidal capacity of peritonela macrophages induced by the direct effect of chlorine or by the reduction of the amount of endogenous endotoxins due to the bactericidal effect of chlorine.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The morphological sequence of Trypanosoma rangeli development in the body cavity of Rhodnius prolixus is described. The metacyclic trypanosome is the product of successive division and transformation during the intra and extracellular development in the haemocoele. The significance of the early invasion of T. rangeli into the haemolymph is discussed. The epidemiological importance of the developmental pattern of T. rangeli in the vectors haemolymph and the host-response to the parasite are considered.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

A description of the species Lymnaea diaphana King, 1830 is presented, on the basis of material collected at its type-locality, San Gregorio, on the north coast of the Strait of Magellan, in the Chilean province of Magallanes. It may be identified by the following characters taken together: adult shell over 10 mm in length, whorls inflated, regularly convex, separated by a well-marked suture, aperture ovate occupying about half the shell length; renal organ forming an approximately right angle with the ureter; pouch of the oviduct well noticeable high on the right ventral surface and on the right side of the nidamental gland; uterus bent to the right into an approximately right angle; body of the spermatheca projected into the pulmonary cavity and adhered to the pericardium and to the roof of the pulmonary cavity; spermiduct highly sinuous, folding dorsalward between the left half of the oviduct and the left shoulder of the nidamental gland, and then winding on ventralward to reach the prostate on the middle line; prostate voluminous, convex on the left, pushed in on the right, with a deep dorsal furrow corresponding to a fold which projects into the prostatic lumen and is more developed at the fore half of the organ; apical end of the penial sheath with about six minute protuberances corresponding to inner chambers; prepuce from about as long about twice as long as the penial sheath, with some variation beyond those limits; lateral teeth of the radula basically tricuspid, with a usually simple ectocone which may show a bifid or trifid point. A diagnosis between lymnaea diaphana and three other lymnaeids which also occur in South America and were previously studied by the author - L. columella, L. viatrix and L. rupestris - is presented.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

BACKGROUND: Only a few studies have explored the relation between coffee and tea intake and head and neck cancers, with inconsistent results. METHODS: We pooled individual-level data from nine case-control studies of head and neck cancers, including 5,139 cases and 9,028 controls. Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (95% CI), adjusting for potential confounders. RESULTS: Caffeinated coffee intake was inversely related with the risk of cancer of the oral cavity and pharynx: the ORs were 0.96 (95% CI, 0.94-0.98) for an increment of 1 cup per day and 0.61 (95% CI, 0.47-0.80) in drinkers of >4 cups per day versus nondrinkers. This latter estimate was consistent for different anatomic sites (OR, 0.46; 95% CI, 0.30-0.71 for oral cavity; OR, 0.58; 95% CI, 0.41-0.82 for oropharynx/hypopharynx; and OR, 0.61; 95% CI, 0.37-1.01 for oral cavity/pharynx not otherwise specified) and across strata of selected covariates. No association of caffeinated coffee drinking was found with laryngeal cancer (OR, 0.96; 95% CI, 0.64-1.45 in drinkers of >4 cups per day versus nondrinkers). Data on decaffeinated coffee were too sparse for detailed analysis, but indicated no increased risk. Tea intake was not associated with head and neck cancer risk (OR, 0.99; 95% CI, 0.89-1.11 for drinkers versus nondrinkers). CONCLUSIONS: This pooled analysis of case-control studies supports the hypothesis of an inverse association between caffeinated coffee drinking and risk of cancer of the oral cavity and pharynx. IMPACT: Given widespread use of coffee and the relatively high incidence and low survival of head and neck cancers, the observed inverse association may have appreciable public health relevance.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

During the schistosomiasis infection there is a [quot ]dance of the cells[quot ], varying from site to site and related to the time of infection. 1 - Eosinophil levels exhibit a bimodal pattern, with the first peak related to the egg deposition and maturation and increased Kupfferian hyperplasia; the second peak precedes the death of some adult worms; 2 - The peritoneal eosinophilic levels are inversely proportional to the blood eosinophilic levels; 3 - Eosinopoiesis in the bone marrow begins at day 40, reaching the highest levels at day 50 and coincides with hepatic eosinophilic and neutrophilic metaplasia; 4 - Peritoneal mast cell levels present a bimodal pattern similar to the blood eosinophils, and inverse to the peritoneal eosinophils. They also show a cyclic behaviour within the hepatic and intestinal granulomas. Integral analysis of the events related to the eosinophils in the blood, bone marrow, peritoneal cavity and hepatic and intestinal granulomas allows the detection of two important eosinophilic phases: the first is due to mobilization and redistribution of the marginal pool and the second originates from eosinophilic production in the bone marrow and liver. The productive phase is characterized by an increase in the number of eosinophils and monocyte/macrophages, and a decrease in neutrophils and stabilization of megakariocytes and erithroid lineages.