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Large numbers of pancake tortoises (Malacochersus tornieri) and Horsfield tortoises (Testudo horsfieldii) in three consignments imported into Japan died soon after arrival. Some tortoises in the first consignment were dead on arrival. Postmortem examination of two of the pancake tortoises and four of the Horsfield tortoises revealed necrotizing lesions of the oral mucosa in both species, primarily in the tongue. Eosinophilic to amphophilic inclusion bodies were visible in the nuclei of mucosal epithelial cells in the lesions. Similar inclusion bodies were observed in the liver, spleen, adrenal glands, stomach, lungs, kidneys, small and large intestines, pancreas, and cerebrum of the pancake tortoises and in the liver, spleen, and pancreas of the Horsfield tortoises. Electron microscopic examination of the cells containing inclusion bodies showed herpesvirus-like particles about 100 nm in diameter in the cytoplasm. Nested polymerase chain reaction analysis using a herpesvirus consensus primer method confirmed the presence of a characteristic herpesvirus base sequence in tissue from these lesions. 相似文献
164.
Miller RL Suits AG Houston PL Toumi R Mack JA Wodtke AM 《Science (New York, N.Y.)》1994,265(5180):1831-1838
Highly vibrationally excited O(2)(X(3)sigmag(-), v >/= 26) has been observed from the photodissociation of ozone (O(3)), and the quantum yield for this reaction has been determined for excitation at 226 nanometers. This observation may help to address the "ozone deficit" problem, or why the previously predicted stratospheric O(3) concentration is less than that observed. Recent kinetic studies have suggested that O(2)(X(3)sigmag(-), v >/= 26) can react rapidly with O(2) to form O(3) + O and have led to speculation that, if produced in the photodissociation of O(3), this species might be involved in resolving the discrepancy. The sequence O(3) + hv --> O(2)(X(3)sigmag(-), v >/= 26) + O; O(2)(X(3)sigmag(-), v >/= 26) + O(2) --> O(3) + O (where hv is a photon) would be an autocatalytic mechanism for production of odd oxygen. A two-dimensional atmospheric model has been used to evaluate the importance of this new mechanism. The new mechanism can completely account for the tropical O(3) deficit at an altitude of 43 kilometers, but it does not completely account for the deficit at higher altitudes. The mechanism also provides for isotopic fractionation and may contribute to an explanation for the anomalously high concentration of heavy O(3) in the stratosphere. 相似文献
165.
Isolation and characterization of bacteria causing mortality in early stage larvae of captive‐bred Japanese eels (Anguilla japonica Temminck & Schlegel) 下载免费PDF全文
Gentoku Nakase Masaharu Tokuda Kazuharu Nomura Hideki Tanaka 《Aquaculture Research》2015,46(11):2637-2643
Bacteria with lethal effect on eel larvae were isolated from moribund captive‐bred eel larvae and their 16S rRNA gene sequences were analysed. Nucleotide sequence of 10 isolates showed highest similarity with Lacinutrix algicola, Crocinitomix catalasitica and Pseudoalteromonas rubra. Age‐dependent changes in the susceptibility of eel larvae were observed in response to challenge by a highly lethal isolate. Compared with 10 and 11 days after hatching (DAH), larval susceptibility to the highly lethal isolate was lower at 18 DAH. We found that the bacterial isolates have lethal effect on the captive‐bred eel larvae, especially at the early developmental stage. These results will be useful to establish appropriate culture practices for eel larvae that will improve the success of mass production of glass eels for aquaculture. 相似文献
166.
The expression of estrogen receptor-alpha (ER) and progesterone receptor (PR) in normal, hyperplastic, and neoplastic endometrium in rabbits was evaluated by immunohistochemistry. The tissues evaluated were 27 normal uteri, 19 cases with endometrial hyperplasia, and 42 adenocarcinomas. Sixteen of 27 cases of normal uteri (59.3%) and 13 out of 19 hyperplasias (68.4%) stained positive with both ER-alpha and PR. Adenocarcinomas were further subdivided into 26 papillary and 16 tubular/solid adenocarcinomas. Papillary adenocarcinoma infiltrated the myometrium late in the disease and caused attenuation of the myometrium. In contrast, tubular/solid adenocarcinoma invaded into the deep myometrium early in the disease without thinning of the myometrium. Twenty-one cases out of 26 (80.8%) cases of papillary adenocarcinoma were both ER-alpha and PR negative, whereas 15 out of 16 (93.8%) of the tubular/solid adenocarcinomas were positive for ER-alpha, PR, or both. The total immunoreactive scores of ER-alpha, PR, and mode of myometrial invasion were significantly different between histopathologic types. This suggests that there may be 2 different developmental pathways for uterine adenocarcinomas in the rabbit. 相似文献
167.
S. Ieiri T. Nomura H. Hirooka M. Satoh 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2004,121(2):90-100
Using Monte Carlo simulation, two schemes of restricted selection were compared under various combinations of genetic parameters and constraints on the genetic gains. The first selection scheme is the combination of best linear unbiased prediction (BLUP) evaluation and linear programming technique (BLUP + LP), and the second one is based on the restricted BLUP selection (RBLUP). Selection for two traits was supposed, in which animals were selected to maximize the genetic gain in trait 2 (Δg2) under a proportional restriction on the genetic gain in trait 1 (Δg1) to satisfy the intended ratio (Δg1:Δg2). Little differences were found between the two selection schemes with respect to the genetic gains averaged over replicates. However, in all the cases studied, the variance of genetic gains among replicates under BLUP + LP selection was smaller and less sensitive to the genetic parameters and the intended restriction than RBLUP selection. Under the situations of antagonistic selection, the difference tended to be larger. When the heritabilities of the two traits were different, RBLUP selection remarkably increased the variance of genetic gain in a trait with a higher heritability. These results suggest that BLUP + LP selection should always be preferable to RBLUP selection because of the smaller risk of selection. This choice is especially important for the situation where the genetic parameters act as limiting factors for the achievement of intended genetic gains. 相似文献
168.
Nomura T 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》1997,114(1-6):13-21
SUMMARY: To obtain a simple formula for predicting variation in selection response, the drift variance of selection response has been approximated by that under random selection. Using computer simulation, the validity of this approximation was examined under various combinations of population size, heritability, and proportion selected. It was shown that the approximation gives a good prediction when the heritability of the selected trait is low, but produces a serious error when applied to a trait with high heritability. However, when the approximation was used for the prediction of coefficient of variation of selection response, a satisfactory prediction was obtained in all cases studied. Although this predictor includes a coincidental factor, it may be used as a criterion for determining the population size required for selection programmes. ZUSAMMENFASSUNG: Simulationsuntersuchung über Selektionserfolg und notwendige Populationsgr??en für Selektions-programme Zur Sch?tzung der Variabilit?t von Selektionserfolgen wurde die Driftvarianz durch die bei Zufallspaarung erwartete approximiert. Die Gültigkeit dieser Approximation wurde an verschiedenen Kombinationen von Populationsgr??e, Heritabilit?t und Remontierungsprozentsat überprüft. Die Approximation ergibt gute Sch?tzwerte bei geringer Heritabilit?t, aber erhebliche Fehler bei hoher. Allerdings konnte der Variationskoeffizient des Selektionserfolges in allen F?llen zufriedenstellend gesch?tzt werden. Obwohl dies auf über-bzw. Untersch?tzung von Z?hler wie Nenner zurückzuführen ist, kann es als Kriterium zur Bestimmung der bei Selektionsprogrammen notwendigen Populationsgr??e verwendet werden. 相似文献
169.
T Ito Y Kawaoka A Nomura K Otsuki 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(8):955-958
The distribution of specific receptors on target organs is a major factor in the host range restriction of influenza A viruses. To assess the correlation between host receptors and the receptor specificity of influenza A viruses from sea mammals, we examined the receptors for influenza A virus in seal and whale lungs. A binding assay using two sialyloligosaccharide (SAalpha2,3Gal and SAalpha2,6Gal)-specific lectins showed that SAalpha2,3Gal, but not SAalpha2,6Gal, was found in both seal and whale lungs. Correspondingly, seal and whale influenza viruses preferentially recognized SAalpha2,3Gal, but not SAalpha2,6Gal. These results indicate that sialyloligosaccharides present at the replication site of influenza A viruses correlate with the receptor recognition of the viruses isolated from sea mammals. 相似文献
170.