968 resultados para Cats


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Hyphema (hemorrhage within the anterior chamber of the eye) can be caused by several mechanisms and can easily be detected in routine ophthalmic or necroscopic examination as discolored red eye(s). The purpose of this study is to report the cause of hyphema diagnosed as a postmortem finding in dogs and cats. Twenty cases, 14 dogs and six cats of several ages and breeds and of both sexes were included in the study. Hyphema presented as a unilateral (14 cases out of 20) or bilateral (6/20) disorder in dogs and cats and extension of hemorrhage varied from minimal to diffuse. Hyphema was secondary to systemic disease (15/20) or occurred as a primary ocular lesion (5/20) in four dogs and one cat. Primary hyphema was always unilateral. In four of these cases, the cause of hyphema was trauma and remaining case was caused by phacoclastic uveitis in a dog with bilateral hypermature cataract. Various causes of bleeding disorders were found related to secondary hyphema: in decreasing order of frequency, they included vasculitis (8/15), systemic hypertension (5/15), and acquired coagulopathies (2/15). Vasculitis due to feline infectious peritonitis accounted for half of the cases (n=3) of systemic hyphema in cats. The various pathological aspects and pathogenesis of hyphema in dogs and cats are described and discussed.

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To improve the understanding of implications of Campylobacterspp. infections in pets and children of different environments were analysed 160 faecal samples from children and 120 from pets (103 dogs and 17 cats). Campylobacter spp. were detected in 6.87% of the children and in 18.3% of the dogs and cats. From 33 stool samples positive for Campylobacter spp., 57.6% were identified as C. jejuni, and 33.4% were identified as C. coli. More than 50% of the isolates in pets were resistant to ceftiofur, sulphazotrim, norfloxacin and tetracycline. In humans, most of the isolates were resistant to amoxicillin, cefazolin, ceftiofur, erythromycin and norfloxacin. From 19 isolates of C. jejuni, 11 isolates from children and 5 from dogs contained two to four of the virulence genes flaA, pldA, cadF or ciaB.We found an association between the presence of virulence genes and diarrhoea. Furthermore, an association was observed between the presence of Campylobacter spp. and diarrhoea in dewormed pets with blood picture suggestive of bacterial infection, and the therapeutic use of antibiotics was associated with more positive detection of Campylobacterspp. in the faeces of pets. Our data indicate that virulent strains of Campylobacter spp. can be risk factor to diarrhoea in animals, and that high resistance to antimicrobial agents is common in pets.

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Abstract: Tritrichomonas foetus, a parasite well known for its significance as a venereally transmitted pathogen in cattle, has been identified as a cause of chronic large bowel diarrhea in domestic cats in many countries of the world. In Brazil, several studies on the diagnosis of bovine trichomoniasis have been performed, but until now, no study was made regarding feline trichomoniasis. Thus, this is the first study to report the occurrence of T. foetus and Pentatrichomonas hominis in cats using morphological and molecular analysis. Feces from 77 cats were examined, four of which (5.2%) were positive for the presence of parabasalids. Morphological analysis of stained smears revealed piriform trophozoites showing the three anterior flagella, elongated nucleus and axostyle ending abruptly in fillet, characteristic of T. foetus. In scanning and transmission electron microscopy, identification characters similar to those previously reported for T. foetus were observed. The cultures containing trophozoites were submitted for molecular analysis, which resulted positive for T. foetus DNA using specific primers (TFR3 and TFR4), and all samples were positive and subjected to sequencing in which they showed 99.7-100% similarity with another isolate sequencing of T. foetus (JX960422). Although no trophozoite with consistent morphology of P. hominis has been visualized in the samples, differential diagnosis was performed using specific primers for P. hominis (TH3 and TH5) amplicon. In three of the four samples (3.89%) sequencing revealed 100% similarity when compared with another sequence of P. hominis deposited in Genbank (KC623939). Therefore, the present study revealed through the diagnostic techniques employed the simultaneous infection by T. foetus and P. hominis in the feces of cats. However, it was necessary to use more than one technique for the diagnosis of the co-infection. These results demonstrate the importance of a correct diagnosis to allow an appropriate treatment by the veterinarian.

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Previous data from our laboratory have indicated that nitric oxide (NO) acting at the presynaptic level increases the amplitude of muscular contraction (AMC) of the phrenic-diaphragm preparations isolated from indirectly stimulated rats, but, by acting at the postsynaptic level, it reduces the AMC when the preparations are directly stimulated. In the present study we investigated the effects induced by NO when tetanic frequencies of stimulation were applied to in vivo preparations (sciatic nerve-anterior tibial muscle of the cat). Intra-arterial injection of NO (0.75-1.5 mg/kg) induced a dose-dependent increase in the Wedensky inhibition produced by high frequencies of stimulation applied to the motor nerve. Intra-arterial administration of 7.2 µg/kg methylene blue did not produce any change in AMC at low frequencies of nerve stimulation (0.2 Hz), but antagonized the NO-induced Wedensky inhibition. The experimental data suggest that NO-induced Wedensky inhibition may be mediated by the guanylate cyclase-cGMP pathway

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The effects of methylmercury (MeHg) on histochemical demonstration of the NADPH-diaphorase (NADPH-d) activity in the striate cortex were studied in 4 adult cats. Two animals were used as control. The contaminated animals received 50 ml milk containing 0.42 µg MeHg and 100 g fish containing 0.03 µg MeHg daily for 2 months. The level of MeHg in area 17 of intoxicated animals was 3.2 µg/g wet weight brain tissue. Two cats were perfused 24 h after the last dose (group 1) and the other animals were perfused 6 months later (group 2). After microtomy, sections were processed for NADPHd histochemistry procedures using the malic enzyme method. Dendritic branch counts were performed from camera lucida drawings for control and intoxicated animals (N = 80). Average, standard deviation and Student t-test were calculated for each data group. The concentrations of mercury (Hg) in milk, fish and brain tissue were measured by acid digestion of samples, followed by reduction of total Hg in the digested sample to metallic Hg using stannous chloride followed by atomic fluorescence analysis. Only group 2 revealed a reduction of the neuropil enzyme activity and morphometric analysis showed a reduction in dendritic field area and in the number of distal dendrite branches of the NADPHd neurons in the white matter (P<0.05). These results suggest that NADPHd neurons in the white matter are more vulnerable to the long-term effects of MeHg than NADPHd neurons in the gray matter.

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Although it has been demonstrated that nitric oxide (NO) released from sodium nitrite induces tetanic fade in the cat neuromuscular preparations, the effect of L-arginine on tetanic fade and its origin induced by NO have not been studied in these preparations. Furthermore, atropine reduces tetanic fade induced by several cholinergic and anticholinergic drugs in these preparations, whose mechanism is suggested to be mediated by the interaction of acetylcholine with inhibitory presynaptic muscarinic receptors. The present study was conducted in cats to determine the effects of L-arginine alone or after pretreatment with atropine or 1H-[1,2,4]oxadiazole [4,3-a]quinoxalin-1-one (ODQ) on neuromuscular preparations indirectly stimulated at high frequency. Drugs were injected into the middle genicular artery. L-arginine (2 mg/kg) and S-nitroso-N-acetylpenicillamine (SNAP; 16 µg/kg) induced tetanic fade. The Nw-nitro-L-arginine (L-NOARG; 2 mg/kg) alone did not produce any effect, but reduced the tetanic fade induced by L-arginine. D-arginine (2 mg/kg) did not induce changes in tetanic fade. The tetanic fade induced by L-arginine or SNAP was reduced by previous injection of atropine (1.0 µg/kg) or ODQ (15 µg/kg). ODQ alone did not change tetanic fade. The data suggest that the NO-synthase-GC pathway participates in the L-arginine-induced tetanic fade in cat neuromuscular preparations. The tetanic fade induced by L-arginine probably depends on the action of NO at the presynaptic level. NO may stimulate guanylate cyclase increasing acetylcholine release and thereby stimulating presynaptic muscarinic receptors.

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Beat-sukupolvi, opiskelijoiden poliittinen aktiivisuus ja hipit olivat tunnettuja ilmiöitä Yhdysvalloissa 1950- ja 1960-luvuilla. Ilmiöillä oli paljon yhteistä ja ne vaikuttivat toisiinsa merkittävästi. Tätä yhteyttä ei aina tuoda esiin. Tämä tutkielma tuo esiin sen, miten The New York Times kirjoitti ilmiöistä. Tutkimus kertoo myös, miten The New York Times yhdistää ilmiöt keskenään. Sen lisäksi tulee esiin The New York Timesin näkemys ilmiöiden taustoista suhteessa nuorisokulttuuriin. Tutkimuksen kohteena on The New York Timesin lehtiartikkeleita vuosilta 1952-1969. Tutkimuksen pääkysymykset ovat: Miten The New York Times suhtautui beat-sukupolveen ja nuorisokulttuurin muutokseen? Miten The New York Times suhtautui yliopisto-opiskelijoihin ja heidän suhteeseensa nuorisokulttuurin muutokseen sekä miten The New York Times näkee hippien muuttavan yhteiskuntaa? Ensimmäistä pääkysymystä tarkastelen kahden alakysymyksen kautta: Miten beat-sukupolven synty esitetään The New York Timesissa, ja toisaalta millaisen kuvan The New York Times antaa beat-sukupolven vaikutuksesta nuorisoon? Toista pääkysymystä käsittelen kysymällä: Miten The New York Times näki nuorten poliittisen vaikuttavuuden nousun ja miten lehti suhtautui ajanjakson yliopistomellakoihin?. Kolmannessa luvussa tarkastelen pääkysymystä kysymällä: Keitä hipit olivat, ja olivatko hipit poliittisesti aktiivisia vai ei? Tutkimuksesta selviää, että The New York Times pyrkii kuvaamaan ilmiöitä mahdollisimman objektiivisesti. Lehti antaa ilmiöitä kuvatessa asioihin hyvin perehtyneiden henkilöiden esittää ilmiö. Sen jälkeen lehti antaa lukijoiden ja muiden asiantuntijoiden kommentoida. The New York Times näkee näiden ilmiöiden yhteyden ja se tulee voimakkaasti esille laajoissa artikkeleissa. Lyhyemmissä uutisissa yhteyttä ei aina näe, ja terminologia on yleistävämpi, tekstin eri tarkoitusperän takia. Kaiken kaikkiaan The New York Times tuo esiin mahdollisimman vähän moralisoivaa kuvaa ilmiöistä ja tuo esiin niiden keskinäisiä suhteita. Tuloksista näkee, että The New York Times on arvoiltaan vapaamielinen lehti, joka uutisoi, näiden aiheiden perusteella, kattavasti koko Yhdysvaltoja koskevista tapahtumista.

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Les lésions de la moelle épinière ont un impact significatif sur la qualité de la vie car elles peuvent induire des déficits moteurs (paralysie) et sensoriels. Ces déficits évoluent dans le temps à mesure que le système nerveux central se réorganise, en impliquant des mécanismes physiologiques et neurochimiques encore mal connus. L'ampleur de ces déficits ainsi que le processus de réhabilitation dépendent fortement des voies anatomiques qui ont été altérées dans la moelle épinière. Il est donc crucial de pouvoir attester l'intégrité de la matière blanche après une lésion spinale et évaluer quantitativement l'état fonctionnel des neurones spinaux. Un grand intérêt de l'imagerie par résonance magnétique (IRM) est qu'elle permet d'imager de façon non invasive les propriétés fonctionnelles et anatomiques du système nerveux central. Le premier objectif de ce projet de thèse a été de développer l'IRM de diffusion afin d'évaluer l'intégrité des axones de la matière blanche après une lésion médullaire. Le deuxième objectif a été d'évaluer dans quelle mesure l'IRM fonctionnelle permet de mesurer l'activité des neurones de la moelle épinière. Bien que largement appliquées au cerveau, l'IRM de diffusion et l'IRM fonctionnelle de la moelle épinière sont plus problématiques. Les difficultés associées à l'IRM de la moelle épinière relèvent de sa fine géométrie (environ 1 cm de diamètre chez l'humain), de la présence de mouvements d'origine physiologique (cardiaques et respiratoires) et de la présence d'artefacts de susceptibilité magnétique induits par les inhomogénéités de champ, notamment au niveau des disques intervertébraux et des poumons. L'objectif principal de cette thèse a donc été de développer des méthodes permettant de contourner ces difficultés. Ce développement a notamment reposé sur l'optimisation des paramètres d'acquisition d'images anatomiques, d'images pondérées en diffusion et de données fonctionnelles chez le chat et chez l'humain sur un IRM à 3 Tesla. En outre, diverses stratégies ont été étudiées afin de corriger les distorsions d'images induites par les artefacts de susceptibilité magnétique, et une étude a été menée sur la sensibilité et la spécificité de l'IRM fonctionnelle de la moelle épinière. Les résultats de ces études démontrent la faisabilité d'acquérir des images pondérées en diffusion de haute qualité, et d'évaluer l'intégrité de voies spinales spécifiques après lésion complète et partielle. De plus, l'activité des neurones spinaux a pu être détectée par IRM fonctionnelle chez des chats anesthésiés. Bien qu'encourageants, ces résultats mettent en lumière la nécessité de développer davantage ces nouvelles techniques. L'existence d'un outil de neuroimagerie fiable et robuste, capable de confirmer les paramètres cliniques, permettrait d'améliorer le diagnostic et le pronostic chez les patients atteints de lésions médullaires. Un des enjeux majeurs serait de suivre et de valider l'effet de diverses stratégies thérapeutiques. De telles outils représentent un espoir immense pour nombre de personnes souffrant de traumatismes et de maladies neurodégénératives telles que les lésions de la moelle épinière, les tumeurs spinales, la sclérose en plaques et la sclérose latérale amyotrophique.

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Les effets des lésions de la moelle épinière sur la locomotion sont souvent évalués sur un tapis roulant avec une surface plane, ce qui demande peu d’implication active des structures supraspinales. L’objectif du présent travail est d’évaluer si un type d’entraînement nécessitant une plus grande part de contrôle volontaire (c.-à-d. supraspinal) pourrait améliorer la récupération de la marche chez le chat après une hémilésion unilatérale spinale au niveau thoracique (T10). Pour ce faire, pendant 6 semaines les chats ont été entrainés sur un tapis roulant conventionnel ou sur un tapis-échelle roulante, tâche requérant un placement des pattes plus précis. Les paramètres de la marche ont été évalués par cinématique et électromyographie (EMG) avant et une fois par semaine pendant 6 semaines après lésion. Nos résultats comparant la marche sur tapis conventionnel à celle sur échelle roulante montrent des différences dans les excursions angulaires et les couplages entre les membres. On observe aussi des différences dans l’amplitude des EMG notamment une augmentation de la deuxième bouffée du muscle Semitendineux (St) sur l’échelle roulante. Après l’hémilésion spinale cette bouffée disparait du côté de la lésion tandis qu’elle est maintenue du côté intact. Après l’entrainement sur échelle roulante, on observe des changements de trajectoire de la patte et une disparition du pied tombant (foot drag) qui suggèrent une amélioration du contrôle de la musculature distale. Nos résultats montrent que le patron locomoteur observé sur tapis conventionnel est influencé par le type d’entraînement procuré. De plus, certains paramètres de la locomotion suggèrent que l’entraînement sur échelle roulante, qui requiert plus de contrôle supraspinal, favorise une meilleure récupération de la marche après lésion spinale.

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Colección de poemas que tratan de animales, a veces, absurdos, y disfrazados, también, de forma absurda, rodeados asimismo, de objetos absurdos.

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Predation by house cats (Felis catus) is one of the largest human-related sources of mortality for wild birds in the United States and elsewhere, and has been implicated in extinctions and population declines of several species. However, relatively little is known about this topic in Canada. The objectives of this study were to provide plausible estimates for the number of birds killed by house cats in Canada, identify information that would help improve those estimates, and identify species potentially vulnerable to population impacts. In total, cats are estimated to kill between 100 and 350 million birds per year in Canada (> 95% of estimates were in this range), with the majority likely to be killed by feral cats. This range of estimates is based on surveys indicating that Canadians own about 8.5 million pet cats, a rough approximation of 1.4 to 4.2 million feral cats, and literature values of predation rates from studies conducted elsewhere. Reliability of the total kill estimate would be improved most by better knowledge of feral cat numbers and diet in Canada, though any data on birds killed by cats in Canada would be helpful. These estimates suggest that 2-7% of birds in southern Canada are killed by cats per year. Even at the low end, predation by house cats is probably the largest human-related source of bird mortality in Canada. Many species of birds are potentially vulnerable to at least local population impacts in southern Canada, by virtue of nesting or feeding on or near ground level, and habitat choices that bring them into contact with human-dominated landscapes where cats are abundant. Because cat predation is likely to remain a primary source of bird mortality in Canada for some time, this issue needs more scientific attention in Canada.

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Even though they are fed daily by their owners, free-ranging pet cats Felis catus may kill wild birds and, given their high densities (typically > 200 cats/km(2)), it has been postulated that cat predation could be a significant negative factor affecting the dynamics of urban bird populations. In this study, we: (1) used questionnaire surveys in 10 sites within the city of Bristol, UK, to estimate cat density; (2) estimated the number of birds killed annually in five sites by asking cat owners to record prey animals returned home; and then (3) compared the number of birds killed with breeding density and productivity to estimate the potential impact of cat predation. In addition, we (4) compared the condition of those birds killed by cats versus those killed in collisions, e.g. window strikes. Mean (+/- sd) cat density was 348 +/- 86 cats/km(2) (n = 10 sites); considering the eight species most commonly taken by cats, the mean ratios of adult birds/cats and juvenile birds/cats across the five sites were 1.17 +/- 0.23 and 3.07 +/- 0.74, respectively. Approximately 60% of the cats studied for up to 1 year at each site never returned any prey home; despite this, the estimated number of birds killed was large relative to their breeding density and productivity in many sites. Across species, cat-killed birds were in significantly poorer condition than those killed following collisions; this is consistent with the notion that cat predation represents a compensatory rather than additive form of mortality. Interpretation of these results is, however, complicated by patterns of body mass regulation in passerines. The predation rates estimated in this study would suggest that cats were likely to have been a major cause of mortality for some species of birds. The effect of cat predation in urban landscapes therefore warrants further investigation. The potential limitations of the current study are discussed, along with suggestions for resolving them.