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排序方式: 共有1380条查询结果,搜索用时 15 毫秒
1.
Maud Lafortune Sherman O Canapp Darryl Heard Lisa L Farina 《Journal of zoo and wildlife medicine》2004,35(1):104-106
Bats in captivity reproduce well and contraceptive techniques are needed. In initial attempts at vasectomy using a prescrotal approach, it was difficult to identify the mesoductus deferens. The technique described here uses a scrotal approach with exteriorization of the testis, followed by identification and ligation of the mesoductus deferens. Nine Egyptian fruit bats (Rousettus aegyptiacus) underwent vasectomy for this study. No postoperative complications were seen (n = 18 testes), but some of the testes (5/18, 27%), which previously moved freely from the scrotum to the abdominal cavity, were still adhered to the scrotal sac 14 mo postoperatively. This technique appears safe, is fast, and is relatively easy to perform. 相似文献
2.
Characteristics of free-roaming cats and their caretakers 总被引:1,自引:0,他引:1
OBJECTIVES: To describe the characteristics of unowned, free-roaming cats and their caretakers who participated in a trap-neuter-return (TNR) program and to determine the effect of the program on free-roaming cat colonies. DESIGN: Prospective study. SAMPLE POPULATION: 101 caretakers of 920 unowned, free-roaming cats in 132 colonies in north central Florida. RESULTS: Most (85/101; 84%) caretakers were female. The median age was 45 years (range, 19 to 74 years). Most (89/101; 88%) caretakers owned pets and of those, most (67/101; 66%) owned cats. The major reasons for feeding free-roaming cats were sympathy and love of animals. Most caretakers reported that the cats they cared for were too wild to be adopted, but many also reported that they considered the cats to be like pets. The total surveyed cat population was 920 before participation in TNR and 678 after TNR. Mean colony size was 7 cats before TNR and 5.1 cats after TNR. Most cats lived on the caretaker's property. At the time of the survey, 70% (644/920) of the cats had been neutered. CONCLUSIONS AND CLINICAL RELEVANCE: The decrease in the surveyed free-roaming cat population was attributed to a reduction in births of new kittens, adoptions, deaths, and disappearances. Recognition of the human-animal bond that exists between caretakers and the feral cats they feed may facilitate the development of effective control programs for feral cat populations. 相似文献
3.
The African Penguin (Spheniscus demersus) has suffered population declines and is listed in the IUCN Red List as Endangered. The species is endemic to the coast of southern Africa, and breeding colonies are distributed on the south-western coast of Africa. Currently, African Penguins are being kept in zoo and aquarium facilities throughout South Africa. In this study, molecular genetic data based on 12 microsatellite markers from 1 119 African Penguin samples from four facilities were generated in order to determine the level of genetic variation, population structure and differentiation, and effective population size to assist in the development of an effective captive management plan. Expected heterozygosity ranged from 0.57 to 0.62, and allelic richness from 4.2 to 5.1. However, based on differences between first- and second-generation captive birds, we conclude that the ex situ population is at risk of losing genetic variability in the future and management programmes should include exchange of birds between captive facilities in order to induce gene flow and increase effective population size. Adding individuals from in situ populations should also be considered in the future in cases where these birds cannot be rehabilitated. Molecular genetic analyses of wild penguin populations should be carried out for comparison, and to ascertain to what degree ‘in situ genetic diversity’ is represented among ex situ populations. With regular resampling and analyses, the extent of the effect of processes such as genetic drift on diversity in the ex situ penguin populations will become evident. 相似文献
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Stephanie Scheemaeker Eva Vandermeulen Richard Ducatelle Lisa Stammeleer Nausikaa Devriendt Tom Roggeman Sylvie Daminet 《Veterinary and comparative oncology》2023,21(2):349-356
Currently, a histological diagnosis of highly vascularized canine (c) thyroid carcinoma (TC) is primarily obtained following excisional biopsy (EB) through thyroidectomy. Non-EBs are contraindicated in unresectable invasive cTCs due to their highly vascularized nature, which subsequently, lack histological diagnosis. We hypothesised ultrasound-guided core needle biopsy (UGCNB) to be a safe biopsy technique to obtain an accurate histological diagnosis in unresectable TCs. Nine client-owned dogs with suspected naturally occurring TC, presented for surgical excision, were included. First, a UGCNB was taken from the cervical tumour, followed by EB. Haemorrhage following UGCNB was evaluated preoperatively and once the tumour was surgically exposed by visual inspection and ultrasonography. Histological analysis, including cell organisation, tumour capsular and vascular invasion, and immunohistochemistry were performed and compared between both biopsy specimens (i.e., UGCNB and EB) of the same dog. Pre- and peroperative visual inspection revealed minor, localised haemorrhage, subsequent to the UGCNB, in 7/9 dogs. Histology of the EBs confirmed TC in 8/9 dogs and was inconclusive in 1/9 dogs. Histology of the UGCNBs revealed neoplastic thyroid tissue in 7/9 UGCNBs and was inconclusive in 1/9 UGCNBs. The remaining UGCNB contained no mass related tissue and was, therefore, excluded. Histological parameters (i.e., cell organisation, tumour capsular and vascular invasion) were not concordant between 6/8 included UGCNBs and their respective EB. Immunolabelling for thyroglobulin and calcitonin was concordant between all eight included UGCNBs and their respective EB. The remaining evaluated immunohistochemical markers (i.e., cyclooxygenase-2 [COX-2], P-glycoprotein and vascular endothelial growth factor [VEGF]) were concordant between the included UGCNBs and the EBs in 6/8 dogs. To conclude, UGCNBs can be safely obtained in suspected cTCs and enable a reliable diagnosis of the thyroid origin, thyroid cell origin and potential therapeutic markers such as COX-2, P-glycoprotein and VEGF. Subsequently, UGCNB enables clinicians to establish an individually tailored treatment plan in dogs with unresectable TC. 相似文献
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Ken CF Chen IJ Lin CT Liu SM Wen L Lin CT 《Journal of agricultural and food chemistry》2011,59(8):3828-3835
Glutaredoxins (Grxs) play important roles in the redox system via reduced glutathione as a reductant. A TcmonoGrx cDNA (1039 bp, EU158772) encoding a putative monothiol Grx was cloned from Taiwanofungus camphorata (formerly named Antrodia camphorata). The deduced amino acid sequence is conserved among the reported monothiol Grxs. Two 3-D homology structures of the TcmonoGrx based on known structures of human Grx3 (pdb: 2DIY_A) and Mus musculus Grx3 (pdb: 1WIK_A) have been created. To characterize the TcmonoGrx protein, the coding region was subcloned into an expression vector pET-20b(+) and transformed into E. coli C41(DE3). The recombinant His6-tagged TcmonoGrx was overexpressed and purified by Ni(2+)-nitrilotriacetic acid Sepharose. The purified enzyme showed a predominant band on 10% sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The enzyme exhibited glutathione reductase (GR) activity via dithionitrobenzoate (DTNB) assay. The Michaelis constant (K(M)) values for GSSG and NADPH were 0.064 and 0.041 mM, respectively. The enzyme's half-life of deactivation at 60 °C was 10.5 min, and its thermal inactivation rate constant (k(d)) was 5.37 × 10(-2) min(-1). The enzyme was active under a broad pH range from 6 to 8. The enzyme retained 50% activity after trypsin digestion at 37 °C for 40 min. Both mutants C(40)→S(40) and C(165)→S(165) lost 40-50% GR activity, whereas the mutant S(168)→C(168) showed a 20% increase in its GR activity. 相似文献
10.
Allan J. Williamson Joao H.N. Soares Noah D. Pavlisko Robert McAlister Council-Troche Natalia Henao-Guerrero 《Veterinary anaesthesia and analgesia》2017,44(4):738-745