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101.
Accurate diagnosis of canine filariosis is essential for choosing correct therapeutic approach. Therefore, reliable methods for discriminating among the different filarial infections in dogs are needed. The authors report simple and highly specific molecular methods that identify the three most common filarial nematodes of European dogs: Dirofilaria immitis, D. repens and Acanthocheilonema (syn. Dipetalonema) reconditum, based on (1) PCR amplifications of mitochondrial DNA (12S rDNA and coxI) with general filarial primers followed by digestion with restriction enzymes that generates band polymorphisms clearly discriminating the three species and (2) PCR amplifications with species-specific primers to support the restriction analysis, in particular in the case of multiple infections.  相似文献   
102.
Cyclosporin is currently considered a new and interesting drug in veterinary dermatology for the treatment of immune-mediated skin diseases, and a safe and effective alternative to immunosuppressive therapy with glucocorticoids. The authors report a case of granulomatous folliculitis and furunculosis and of sebaceous adenitis in two cats and a case of alopecia areata in a dog, successfully controlled with cyclosporin.  相似文献   
103.
New neurons follow the flow of cerebrospinal fluid in the adult brain   总被引:1,自引:0,他引:1  
In the adult brain, neuroblasts born in the subventricular zone migrate from the walls of the lateral ventricles to the olfactory bulb. How do these cells orient over such a long distance and through complex territories? Here we show that neuroblast migration parallels cerebrospinal fluid (CSF) flow. Beating of ependymal cilia is required for normal CSF flow, concentration gradient formation of CSF guidance molecules, and directional migration of neuroblasts. Results suggest that polarized epithelial cells contribute important vectorial information for guidance of young, migrating neurons.  相似文献   
104.
OBJECTIVES: To investigate the use of a capecitabine (CAP)-based regimen after renal transplantation in dogs. STUDY DESIGN: Prospective, pilot study. ANIMALS: Healthy, unrelated, dog erythrocyte antigen (DEA)-matched, adult beagles. METHOD: Standard heterotopic renal transplantation with native nephrectomy was performed in 7 dogs. Dogs received oral, twice daily, CAP (250 mg/m2), cyclosporine-A (CsA) (4 mg/kg), ketoconazole (5 mg/kg), and prednisolone (0.25 mg/kg). After 90 days the surviving dogs were euthanatized and complete necropsy was performed. RESULTS: Seven transplants were performed. All dogs survived surgery. Six dogs had acute neurotoxicity, which resulted in death or euthanasia of 2 dogs within 2 days of surgery. In the remaining dogs, toxicity resolved rapidly with cessation of drug administration. Thereafter, modification of the regimen minimized toxicity. The 5 remaining dogs survived to study end; 4 dogs had no evidence of graft rejection. Necropsy examination was mostly unremarkable in all dogs. There were no major changes in CBC or biochemical values, except for a significant increase in serum calcium. CONCLUSIONS: CAP appeared well tolerated in most dogs. Toxicity occurred but abated with modification of the drug regimen. Efficacy for postoperative immunosuppression cannot be determined by this study, although results are promising. CLINICAL RELEVANCE: CAP-CsA-prednisolone is an effective, oral immunosuppressive regimen for prevention of acute allograft rejection in DEA-matched beagles. Further studies on dose, toxicity, and efficacy compared with current immunosuppressive regimens are needed before use in clinical practice.  相似文献   
105.
BACKGROUND: Swab cytology of ear canals is one of the most useful and rapid methods to assess the presence of external ear infections. Smears are generally stained with rapid Romanowsky-type stains, with or without prior heat fixation. OBJECTIVES: The aim of this study was to compare 4 different methods of fixation and staining of ear swab cytology samples from dogs. METHODS: Eight dogs with otitis externa were selected from a dermatology referral population. A cotton swab was used to obtain ceruminous material from 12 ear canals. Four smears of each swab were prepared on glass slides (randomly identified as A, B, C, or D) and air-dried for cytologic examination. Samples marked A were stained with Dip Quick (Jorgensen Laboratories Inc, Loveland, CO, USA) after heat fixation; samples marked B were stained without heat fixation; samples marked C were heat-fixed and dipped only in the counterstain (the blue reagent) of Dip Quick; and samples marked D were dipped only in the counterstain, without heat fixation. Ten high-power fields (hpf; X100 oil immersion objective) in each slide were evaluated by 2 observers, and total numbers of keratinocytes, yeast, bacteria, and neutrophils were counted. Statistical comparison was performed using an ANOVA model applied after verifying the normal distribution of the data, and using nonparametric sign tests and Wilcoxon signed rank tests. RESULTS: No statistically significant differences were observed in the numbers of keratinocytes, yeast, bacteria, or neutrophils among the 4 staining methods (P > .05), although significant interobserver differences were found. CONCLUSION: We conclude that heat fixation does not improve the quality of ceruminous ear swab samples for cytologic evaluation, and propose a 1-step dip in the blue reagent alone as a rapid method of staining samples from canine ear canals.  相似文献   
106.
Questionnaires potentially have a broad applicability in measuring stress levels in dogs, as owners know their dogs’ behavior and personality better than anyone else. The aim of this research was to evaluate how owners perceive stress in their dogs through understanding of displayed behaviors.The survey was carried out using 1,190 questionnaires completed by dog owners. More than half of respondents were able to correctly identify stress as a short- or long-term alteration of the psychophysical equilibrium that can develop into illness. This ability was higher with higher educational levels. The behavioral indicators of stress most frequently identified by owners were trembling and whining, followed by aggressiveness, excessive barking, and panting. More subtle behaviors such as looking elsewhere, turning head, yawning, and nose licking were more rarely reported, suggesting that few owners are able to correctly interpret and intervene in early stages of stress. The vast majority of respondents indicated that dogs were stressed seldom or only in specific situations. Men generally considered their dogs as experiencing low stress more often than did women, whereas women considered their dogs as being moderately stressed more often than did men.An owner’s ability to recognize behavioral signs of stress is important, as it enables the owner to help the animal to avoid welfare problems, such as stressful situations, and favors a rapid recovery of psychophysical homeostasis by interrupting the progression to overstress and distress. The results show that some owners can help in protecting the welfare of their dogs, but that many owners would benefit from educational efforts to improve their ability to interpret their dogs’ behavior.  相似文献   
107.
Hidden fumonisins have received great attention in the last years as they have been frequently found in maize products in addition to the free forms. Several papers have shown that interaction with macromolecular components such as protein and starch is at the base of the phenomenon: although the nature of the interaction (covalent or not) is still not clarified, the occurrence of hidden forms is generally revealed by the application of an alkaline hydrolysis procedure. In this study, an in vitro digestion model has been applied to raw maize to evaluate the possible release of hidden fumonisins under gastrointestinal conditions. Upon digestion of the food matrix, an increased amount of total detectable fumonisins was observed in comparison with the analysis on the nondigested matrix, an amount even higher than that calculated through the application of the hydrolysis procedure. Besides the analytical issues, our data have serious implications, since consumers may be exposed to a systematic higher risk than that estimated by conventional techniques.  相似文献   
108.
With the purpose of obtaining apple plants with reduced vigour but deep and expanded root apparatus, more adapted for establishment of apple orchards in dry, windy areas and higher altitudes, different interstem/rootstock combinations were compared, using seedling as rootstock and, alternatively, two weak interstocks (M.9 and M.27). For all treatments the plants were grafted at two height from soil (10 and 20 cm), interposing interstock 10 or 20 cm long. Plants with interstock showed lower vegetative growth in comparison with control plants with a reduction of 80% (M.27) and of 50% (M.9) of canopy growth. Moreover, use of interstock determined, as compared with the control plants, an increase of fruit production and average fruit weight. It was noted that increasing the interstock length, caused reduction of plants vigour and fruit production. The results showed that, the combination “Annurca Rossa del Sud”/M.9 (10 cm long)/seedling rootstock (20 cm high) was the most efficient for productivity, early maturing and plant vigour control.  相似文献   
109.
Objectives To describe and evaluate the use of equine amniotic membrane trans‐plantation after lamellar keratectomy for the treatment of corneal sequestrum in cats. Methods Six cats (seven eyes) of various breed and ages with corneal sequestra were treated surgically with lamellar keratectomy and amniotic membrane transplantation. All the sequestra and a small piece of the amniotic membranes used for each surgery were submitted for histopathologic examination. Results Five of the seven eyes showed minimal level of scarring in the cornea and good transparency. No recurrences of the sequestra have been noted during the follow‐up period (3–9 months). One eye had necrosis of the amniotic membrane 2 weeks after the surgery. The sequestrum of this eye showed a high level of bacterial contamination on histopathology. Three months later the same cat developed a descemetocele in the area where the necrotic amniotic membrane was rejected. A second eye developed a perforation under the amniotic membrane two weeks after the surgery. The sequestrum of this eye was deep and without vascularization. Conclusion Amniotic membrane transplantation after lamellar keratectomy was a valid procedure for surgical treatment of corneal sequestrum in cats. The procedure resulted in excellent cosmesis and functional vision in five of seven eyes; although case selection is important, particularly to exclude the very deep and non‐vascularized sequestra.  相似文献   
110.
A case of leishmaniasis in a domestic cat (Felis domesticus) is described. The animal showed a single, nodular lesion on the nose and many nodules of different size on the ears and digital regions of all the paws. Diagnosis was made by microscopic detection of amastigotes in Giemsa-stained smears from the lesions. By monoclonal antibodies the aetiological agent was identified as Leishmania (Leishmania) amazonensis, one of the seven species implicated in human leishmaniasis in Brazil. The clinical signs in feline leishmaniasis are unspecific and similar to those observed in other diseases such as cryptococcosis and in sporotrichosis, commonly found in cats. Leishmaniasis should therefore, be added to the differential diagnosis by feline veterinary practitioners and adequate investigations should carried out for dermal leishmaniasis in the area where the feline infection is detected.  相似文献   
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