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41.
Meningioma is the most common primary brain tumor in cats, although there are few reports about their pathological features. To investigate the histopathological subtypes and immunohistochemical features including expression of cytokeratin and cell adhesion molecules, 45 cases of feline meningioma were examined. The mean age was 12.5 years (range 6–21 years). No statistically significant sex predilection was observed. Regarding the anatomical location of meningioma, tumors mostly developed in the cerebrum, followed by spinal cord and cerebellum, and multiple meningioma was observed in one cat. Microscopically, linear or focal mineralization was observed in 40 cases and cholesterol cleft was observed in 14 cases. Based on histopathological subtypes, there were 15 fibrous, 22 transitional, 2 meningothelial, 5 atypical, and 1 anaplastic meningiomas. These subtypes are classified into grade 1 (39 cases), grade 2 (5 cases), and grade 3 (1 case). There was no significant difference in the Ki-67 index among histological subtypes or grades. Immunohistochemically, the tumor cells were positive for cytokeratin in 5 cases (12.8%), vimentin in 17 cases (43.6%), E-cadherin in 36 cases (92.3%), β-catenin in 21 cases (53.8%), and N-cadherin in 1 case (2.6%), demonstrating the utility of E-cadherin-immunohistochemistry for the diagnosis of feline meningiomas.  相似文献   
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The secretion of prolactin (PRL) is under the dominant and tonic inhibitory control of dopamine (DA); however, we have recently found that salsolinol (SAL), an endogenous DA‐derived compound, strongly stimulated the release of PRL in ruminants. The aim of the present study was to clarify the inhibitory effect of DA on the SAL‐induced release of PRL in ruminants. The experiments were performed from late June to early July. Male goats were given a single intravenous (i.v.) injection of SAL (5 mg/kg body weight (BW)), a DA receptor antagonist (sulpiride, 0.1 mg/kg BW), or thyrotropin‐releasing hormone (TRH, 1 µg/kg BW) before and after treatment with a DA receptor agonist (bromocriptine), and the effect of DA on SAL‐induced PRL release was compared to that on sulpiride‐ or TRH‐induced release. Bromocriptine completely inhibited the SAL‐induced release of PRL (P < 0.05), and the area under the response curve (AUC) for a 120‐min period after the treatment with bromocriptine was 1/28 of that for before the treatment (P < 0.05). Bromocriptine also completely inhibited the sulpiride‐induced release (P < 0.05). The AUC post‐treatment was 1/17 that of pre‐treatment with bromocriptine (P < 0.05). Bromocriptine also inhibited the TRH‐induced release (P < 0.05), though not completely. The AUC post‐treatment was 1/3.8 that of pre‐treatment (P < 0.05). These results indicate that DA inhibits the SAL‐induced release of PRL in male goats, and suggest that SAL and DA are involved in regulating the secretion of PRL. They also suggest that in terms of the regulatory process for the secretion of PRL, SAL resembles sulpiride but differs from TRH.  相似文献   
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Immunohistochemical localization of TGF-alpha and cell proliferation kinetics during liver regeneration after two-thirds partial hepatectomy (PH) were investigated. Twenty-four to 72 hr after PH, appreciable increase in the number of TGF-alpha-positive hepatocytes was observed in zones 1 and 2. At the peak at 36 hr, almost all positive cells were stained in their nuclei. Considerable increase in the BrdU labeling index was observed 24-36 hr after PH with a peak at 24 hr in zones 1 and 2. These results indicated an association between TGF-alpha expression and hepatocyte regeneration. It is suggested that immunohistochemical localization of TGF-alpha may be a useful marker of cell proliferation activity in rat liver.  相似文献   
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Six Wagyu (Japanese Black) steers fitted with a ruminal cannula were used in a split‐plot design experiment comprising a 3 × 3 Latin square design (whole plot) and a randomized blocks design (subplot) to determine the effect of the treatment of potato pulp (PP) with urea and the effect of inclusion levels of PP silage in feed supplement on digestibility, ruminal in situ degradation and ruminal fermentation. The whole plot consisted of 20%, 50% and 80% PP silage (dry matter (DM) basis), with PP silage replacing formula feed. The subplot included untreated or 0.5% (on an as‐fed basis) urea‐treated PP. The treatment of PP with urea showed no effect on DM intake and digestibility. The percentage of the rapidly degradable DM fraction of the urea‐treated PP silage was higher (P < 0.01) and the percentage of its slowly degradable DM fraction was lower (P < 0.01) than for the untreated PP silage. Ruminal ammonia concentration was greater (P < 0.01) for steers fed urea‐treated PP silage than that for steers fed the untreated PP silage. The treatment of PP with urea caused a decrease in the molar proportion of acetate and an increase in the proportion of propionate in ruminal fluid after feeding. The rate of DM degradations in hay (linear, P < 0.01) and in PP silage decreased (linear, P < 0.01) as the inclusion level of PP silage increased. Increasing the inclusion level of PP silage in supplement decreased the effective degradability of DM in hay (linear, P < 0.05) and in PP silage (linear, P < 0.05). An increase in the amount of PP silage increased the molar proportion of acetate (linear, P < 0.01) and decreased the butyrate proportion (linear, P < 0.05) in ruminal fluid. The results suggest that urea treatment of PP facilitates microbial access to starch of PP silage in the rumen and that surplus level of PP silage in supplement have adverse effect on ruminal digestion.  相似文献   
45.
There appears to be strong evidence supporting four major clades of placental mammals: (i) Afrotheria; (ii) Xenarthea; (iii) Euarchontoglires; and (iv) Laurasiathera. This is the first study in which the carbohydrates have been analyzed in the milks of Xenarthea. Our aim was to clarify whether the saccharides of giant anteater milk resemble those of other eutherian species, especially of the Asian elephant, which is one of the Afrotherea. We found that lactose is a dominant saccharide in this milk, as it is in that of most eutherians, and that the milk contains smaller amounts of oligosaccharides, whose structures were determined as Gal(α1‐3)Gal(β1‐4)Glc (isoglobotriose), Neu5Ac(α2‐6)Gal(β1‐4)Glc (6'‐N‐acetylneuraminyllactose), Neu5Gc(α2‐6)Gal(β1‐4)Glc (6'‐N‐glycolylneuraminyllactose), Neu5Ac(α2‐6)Gal(β1‐4)GlcNAc(β1‐3)Gal(β1‐4)Glc (LST c) and Neu5Gc(α2‐6)Gal(β1‐4)GlcNAc(β1‐3)Gal(β1‐4)Glc. This pattern of milk carbohydrates is rather close to that of the milks of other eutherian species. It is notable that the milk contained oligosaccharides with Neu5Gc residues but no oligosaccharides containing α(2‐3) linked Neu5Ac residues such as Neu5Ac(α2‐3)Gal(β1‐4)Glc.  相似文献   
46.
Using path analyses, we investigated relationships between size at release from hatcheries, the early marine growth of juveniles, and adult return rates for chum salmon from five river stocks of Hokkaido, Japan, in relation to sea surface temperature during ocean residence. Marine growth was estimated using scales collected from 11 760 adults of age 0.3 (1980–2004). The growth and survival of each stock appeared to have a different suite of regulatory processes. Interannual variability in return rates was mainly regulated by size at release in two stocks from the Sea of Okhotsk. A similar relationship was found in one stock from the Sea of Japan, but growth during coastal residency also affected their return rates. In two stocks from the Pacific coast of Hokkaido, variability in return rates was not related to size at release or to the coastal growth of juveniles, but with offshore growth in the Sea of Okhotsk, the nursery area for juveniles after leaving Japanese coastal waters. Whereas coastal growth tended to be negatively correlated with size at release in some stocks, offshore growth was positively associated with the August–November sea surface temperature in all stocks. This study confirmed that mortality of juvenile salmon occurred in two phases, during the coastal residency and the late period of the growing season, but the relative importance of both phases varied by stock and region, which probably regulated year‐class strength of Hokkaido chum salmon.  相似文献   
47.
云南稻种冲腿的孕穗期耐冷性QTL分析   总被引:24,自引:6,他引:24  
 利用352 个探针分析了日本品种农林20和云南品种冲腿之间的限制性片段长度多态性(RFLP),从中筛选出157个在农林20和冲腿间显示多态性的探针,其中55个被用于其杂交后代(农林20/冲腿)的70个F3系统的孕穗期耐冷性数量性状位点(QTL)分析。结果初步显示出一些与水稻孕穗期耐冷性有关的QTL,它们主要分布在第1、3、4、5、6、7、8、10和第12染色体上。可能在第3和第7染色体上具有对孕穗期耐冷性作用较大的QTL。  相似文献   
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