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1.
A 3.5-yr-old, 2.5-kg female African penguin (Spheniscus demersus) was diagnosed with a choanal squamous cell carcinoma on the basis of biopsy after a history of choanal ulceration and anorexia with weight loss. Therapeutic modalities included the use of intralesional cisplatin followed by localized, topical cryotherapy with liquid nitrogen. The penguin remained free of clinical disease for a period of 9 mo, at which time a second cryotreatment was performed. The patient has remained free of all signs of choanal carcinoma for a period of 13 mo since the second cryotreatment.  相似文献   
2.
Oral eosinophilic granulomas were diagnosed in 16 tigers (Panthera tigris). All lesions were located on the hard or soft palate and typically consisted of flat or slightly raised circular ulcers. Histologic features of these lesions were essentially identical to those seen in oral eosinophilic granulomas of domestic cats and dogs. No clinical signs were noted in eight cases, though various degrees of inappetence, excessive salivation, and dysphagia were noted in the other eight tigers. Six cases were not treated. Treatment for the remaining 10 cases centered on corticosteroids and additional treatments included surgical removal, cryotherapy, antibiotics, and chlorpheniramine. Treatment with corticosteroids did appear to be effective in some cases, though lesions would worsen after cessation of therapy and no cases were cured. In addition, three cases developed complications possibly related to this corticosteroid therapy. The etiology of these lesions remains unknown, though an underlying allergic condition is likely.  相似文献   
3.
Near extinction of a highly fecund fish: the one that nearly got away   总被引:6,自引:0,他引:6  
It is widely assumed that commercial fisheries of highly fecund species are particularly resilient to exploitation, and that, should populations become seriously diminished, economic constraints will force fishing to cease before biological extinction can occur. Indeed, among commercially exploited marine fishes there is not one confirmed global extinction. Here we document, using nonconventional means, a story that not only questions such assumptions but that should also alert us to how little we know about significant fisheries in some parts of the world. Our case study is that of the highly threatened Chinese bahaba, Bahaba taipingensis, a member of the Sciaenidae (the drums or croakers), and an example of a fecund and commercially important group of fishes that appears to be especially vulnerable to fishing. We also demonstrate that the careful use of informal, or traditional, information can provide a powerful, sometimes unique, means of identifying and assessing the status and history of species that might be quietly slipping away before we learn anything about them.  相似文献   
4.
The following sequence of treatments was administered to a Saint Bernard dog with a primary distal right radius osteosarcoma: 54 days of daily disodium 1-hydroxyethylidenediphosphonate (HEDP) subcutaneous injections; 53 days of HEDP per os ; one 32P-HEDP intravenous injection. During the pretreatment period, there was an extensive increase in calcific tumor growth and osteoblastic proliferation. After the subcutaneous HEDP treatment, almost complete tumor necrosis was seen. After the oral HEDP treatment, only the deepest tumor portion contained active osteoblasts, calcific growth of the tumor was completely blocked, and uptake of 99mTc-Sn-HEDP was reduced to one fourth of the pretreatment uptake. After a single 32P-HEDP dose, large areas of tumor necrosis were evident histopathologically. However, subsequent resumption of cellular activity occurred in the tumor, and the uptake of 99mTc-Sn-HEDP increased to pretreatment values. These data suggest that systemically administered HEDP should be studied further for its possible therapeutic potential in the treatment of osteosarcoma and indicate a need for further study of 32P-HEDP or possibly 33P-HEDP.  相似文献   
5.
6.
The establishment and evaluation of family lines using pedigree information provides an advanced understanding of the variability that exists for complex, economically valuable traits and is a necessary step in the execution of an effective breeding programme. The aim of this study was to assign parentage to mass‐spawned Haliotis midae juveniles using species‐specific microsatellite markers. Screening of wild abalone individuals revealed that the nine loci selected complied with the minimum requirements for parentage analyses: a null allele frequency <5% as well as a high number and frequency of alleles per locus. A total of 598 individuals were genotyped (198 breeding individuals and 400 F1 progeny) from two farms, with parentage results yielding 91% and 90% successful assignment for Farms A and B respectively. This study, therefore, provided the necessary pedigree information required for controlled breeding of individual adult abalone and indicated the usefulness of the panel of microsatellite markers selected for parentage assignment.  相似文献   
7.
The current US corn grading system accounts for the portion of damaged kernels, measured by time-consuming and inaccurate visual inspection. Near infrared spectroscopy (NIRS), a non-destructive and fast analytical method, was tested as a tool for discriminating corn kernels with heat and frost damage. Four classification algorithms were utilized: Partial least squares discriminant analysis (PLS-DA), soft independent modeling of class analogy (SIMCA), k-nearest neighbors (K-NN), and least-squares support vector machines (LS-SVM). The feasibility of NIRS for discriminating normal or viable-germinating corn kernels and soybean seeds from abnormal or dead seeds was also tested. This application could be highly valuable for seed breeders and germplasm-preservation managers because current viability tests are based on a destructive method where the seed is germinated. Heat-damaged corn kernels were best discriminated by PLS-DA, with 99% accuracy. The discrimination of frost-damaged corn kernels was not possible. Discrimination of non-viable seeds from viable also was not possible. Since previous results in the literature contradict the current damage-discrimination results, the threshold of seed damage necessary for NIRS detection should be analyzed in the future. NIRS may accurately classify seeds based on changes due to damage, without any correlation with germination.  相似文献   
8.
BACKGROUND: Ingestion of wilted red maple leaves by horses can result in severe hemolytic anemia and methemoglobinemia. Little is known about what factors influence the outcome of red maple leaf toxicosis in horses. HYPOTHESIS: Our hypothesis was that physical examination findings, clinicopathologic variables or therapeutic modalities may predict outcome in horses with red maple leaf toxicity. ANIMALS: Horses with red maple leaf toxicosis presented to referral hospitals in the southeast region of the United States. METHODS: A multi-institutional retrospective study was designed to identify factors that predict mortality in horses with red maple toxicosis. RESULTS: Thirty-two horses with red maple toxicosis were identified, 19 of which died. Twenty-nine horses presented with anemia and 24 had clinicopathologic evidence of systemic inflammation. Renal insufficiency was identified in 12/30 (41%) horses. Laminitis (9/28) and colic (13/30) also were identified in horses with red maple toxicosis, but development of these 2 conditions did not have a negative effect on short-term survival. Horses with red maple toxicosis that survived to discharge were likely to have developed pyrexia during hospitalization (P = .030). Horses that were treated with a corticosteroid had a significantly increased likelihood of death (P = .045). There was no significant relationship between initial serum hemoglobin concentration, methemoglobin concentration, or percentage methemoglobin and mortality in this horse series. CONCLUSIONS AND CLINICAL IMPORTANCE: This study suggests that information obtained on initial examination cannot be used to accurately predict survival in horses with red maple toxicosis, but horses that receive corticosteroids are unlikely to survive.  相似文献   
9.
余健秀  庞义 《昆虫天敌》1995,17(3):128-137
本文应用DNASIS(V7.12)和PROSIS(V7.12)软件、GenBank(1994.8,Releasee 84.0)和Swiss—Prot(1994.2,Releasee 28.0)数据库对苏云金杆菌(Bacillus Thuringiensis,BT)杀虫晶体蛋白(Insecticidal Crystal Proteins,ICPs)及其编码基因进行了检索,在此基础上对ICPs基因序列结构的同源性、DNA片段总碱基数、晶体蛋白氨基酸数及分子量、晶体蛋白基因编码序列(CodingSequence,CDS)范围、目标生物等进行了比较,发现属同一基因型的不同菌株来源的晶体蛋白基因编码蛋白区的序列几乎完全一样,同源性高达99%,而不同基因型编码的蛋白氨基酸序列则差异较大。文中根据上述资料对100个苏云金杆菌晶体蛋白基因进行归类,将之分为cryⅠ——cryⅧ、cytA、cytB等10类36个亚类,还对晶体蛋白基因分类的有关问题进行了讨论。  相似文献   
10.
Five cases of xanthomatosis in geckos were evaluated, one in a northern green gecko (Naultinus grayi) and the remaining four in three species of leaf-tailed geckos (two Uroplatus henkeli, one U. sikorae, one U. fimbriatus). All geckos were females 3-11 yr of age, were clinically ill on presentation, and either died or were euthanized. Necropsies showed emaciation in three geckos, with white nodular foci on coelomic surfaces in two of these geckos. The other two geckos had no gross abnormalities. Histopathologic examination revealed xanthomatosis involving the coelomic surfaces of four geckos and the ventricles of the brain in all geckos. Xanthomas in the brain were associated with various degrees of hydrocephalus. The lesions were comprised of stacks of clear clefts consistent with cholesterol crystals, and these structures were surrounded by epithelioid macrophages, multinucleated giant cells, and lymphocytes. Four geckos had active folliculogenesis, and two had foci of follicular degeneration and localized yolk coelomitis. In all cases, xanthomatosis was believed to have contributed significantly to morbidity and mortality.  相似文献   
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