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83.
The innervation pattern of vasoactive intestinal polypeptide-immunoreactive (VIP-IR) nerves in the quail internal carotid artery (ICA) and cerebral arterial tree was investigated and compared with that of acetylcholinesterase-positive (AChE-P) nerves. The supply of VIP-IR nerves to the two arterial systems was distinctly richer than that of AChE-P nerves. It was focused mainly on the walls from the distal ICA to the caudal half of the anterior ramus (AR) through the cerebral carotid artery (CCA). Indeed, double staining clearly showed that numerous VIP+/AChE-axons were distributed over these arterial regions where VIP+/AChE+ or AChE+/VIP- axons were sporadic or often lacking. The finding that nerve bundles accompanying the ICA within the carotid canal contained abundant VIP+/AChE- nerve cells suggests that cerebrovascular VIP-IR nerves in the quail have their major source at these neurons and enter the cranial cavity through the CCA. Another significant finding was that a small number of nerve cells, which were mostly stained for AChE alone and occasionally for VIP alone or both, occurred in the major arteries located more rostral than the middle AR. Thus, the quail cerebral arterial tree, at least the rostral segment of the anterior circulation, is multiply innervated by these three distinct categories of the extracranial and intracranial VIP-IR and AChE-P neurons.  相似文献   
84.
The effects of including essential oil cyclodextrin (CD) complexes on ruminal methane and hydrogen production, volatile fatty acid (VFA) and protozoa were studied in vitro. The essential oil CD complexes used in the present study were both αCD and βCD with cineol, eucalyptus, menthol, peppermint, thyme and wasabi. Diluted rumen fluid (60 mL) was incubated anaerobically at 38°C for 6 h with the essential oil CD complex (1–40 mg as oil). Eucalyptus‐αCD reduced methane production by 40% with 10 mg as oil along with decreasing the protozoal number and increasing total VFA and proportion of propionic acid. Both wasabi‐αCD and wasabi‐βCD reduced methane production by 85% and 97%, respectively, with 10 mg as oil, though they increased hydrogen production notably. The protozoal number was unchanged by wasabi‐βCD and decreased to 50% by wasabi‐αCD. Propionic acid was increased by both wasabi‐αCD and wasabi‐βCD. The other essential oil‐CD showed no significant effect on reducing methane production. The combined use of 20 mM of fumaric acid with wasabi‐αCD (1 mg as oil) caused about a 50% depression of methane production compared to the control without increasing hydrogen production. Fumaric acid was more effective than malic acid in reducing methane production. The addition of eucalyptus‐αCD, wasabi‐αCD or wasabi‐βCD together with organic acid to rumen fluid turned out to be effective for reducing methane production with no increase in hydrogen production.  相似文献   
85.
The taste buds of bovine fungiform papillae were studied by light and electron microscopy using both histological and immunohistochemical methods. The taste buds existed in the epithelium of the apical region of the papillae. By electron microscopy, two types of taste cells, namely type I and type II cells, could be classified according to the presence of dense-cored vesicles, the cytoplasmic density and the cell shape. Type I cells were thin, had an electron-dense cytoplasm containing dense-cored vesicles, and possessed long thick apical processes in the taste pore. Type II cells were thick, had an electron-lucent cytoplasm containing many electron-lucent vesicles, rather than dense-cored vesicles, and possessed microvilli in the taste pore. Immunohistochemical staining with an antiserum against gustducin was investigated by both light and electron microscopy using the avidin-biotin complex (ABC) method. Some, but not all, of the type II cells exhibited gustducin immunoreactivity, whereas none of the type I cells showed any immunoreactivity.  相似文献   
86.
选用10头经产荷斯坦种乳牛分为对照和试验两组,以二乘反转法,研究了增加日粮中非降解蛋白质(RUP)的含量对高产奶牛瘤胃发醇、产乳量和乳成分的影响。两组日粮基本相同,试验组日粮是用加热大豆粕替代了对照组日粮中的生大豆粕,使RUP比例提高3.9%。结果表明,RUP比例的提高对瘤胃液氨氮浓度、纤毛虫种类及其数量和挥发性脂肪酸浓度及其组成无显著影响(P>0.1)。试验组牛血浆葡萄糖浓度有下降趋势(P<0.1),尿素氮、总游离氨基酸和必需氨基酸浓度两组间均无明显差异(P>0.1)。虽然两组乳牛干物质采食量无明显差异,但是试验组产乳量、4%脂肪校正乳量、乳糖和无脂固形物生产量显著增加(P<0.05),分别比对照组提高7.1%(2.3kg/d)、6.1%(1.9kg/d)、5.8%(80g/d)和6.8%(180g/d);乳蛋白质和乳脂肪生产量稍有提高,但无明显差异(P>0.1)。试验组比对照组乳蛋白质率低0.09%单位(P<0.1),乳脂率、乳糖率和无脂固形物率低0.06%~0.08%单位(P>0.1),乳脂中脂肪酸比例无明显变化。以上结果显示:提高高产奶牛日粮中RUP比例可增加产奶量,但是同时要想改善乳蛋白质含量为主的乳成分,需要平衡地改善能量、蛋白质乃至葡萄糖营养的供给状况。  相似文献   
87.
The phagocytosis of Vibrio anguillarum by peritoneal macrophages from normal rainbow trout was enhanced by antibody and complement. Treatment of either macrophages or the bacteria by antibody also enhanced opsonisation. Five weeks after immunisation with V anguillarum, the phagocytic activity of macrophages from rainbow trout was increased significantly compared with the activity of those from unvaccinated fish. Although agglutinin titres did not increase until three weeks after immunisation, seven out of 10 fish challenged one week after immunisation survived, indicating that immunised fish had developed resistance to vibrio infection before significant levels of antibody or phagocytic activity became detectable.  相似文献   
88.
Thy-1 expression may influence myofibroblast development. Through the epithelial-mesenchymal transition (EMT), injured renal epithelial cells undergo regression to the metanephric mesenchymal phenotype and then acquire a myofibroblastic nature (expressing α-smooth muscle actin; α-SMA). Because the metanephric blastema differentiates into mesenchymal and renal epithelial cells, we investigated Thy-1 immunoexpression during nephrogenesis in F344 rats in correlation with vimentin and α-SMA expressions. Kidney samples were obtained from fetuses on gestation days 18 and 21, neonates on days 1-18 and adults at 6 weeks of age. Mesangial cells in S-shaped bodies and immature and mature glomeruli continuously expressed both Thy-1 and α-SMA during early nephrogenesis (fetuses and neonates on days 1-9). During early nephrogenesis, loosely-arranged blastemal cell-derived mesenchymal cells in the cortex and medulla also exhibited Thy-1 and α-SMA, although the α-SMA expression was weaker than that of Thy-1. Vimentin expression coincided with that of Thy-1. These findings indicate that the derivation of α-SMA-expressing myofibroblastic cells may be related to mesangial or blastemal cells expressing both Thy-1 and α-SMA. Interestingly, there was a difference in Thy-1 expression between cortical and medullary tubulointerstitial cells from late nephrogenesis (neonates on days 12-18) and those from adults in that the cortical cells reacted faintly or negatively to Thy-1, whereas the medullary cells reacted strongly to Thy-1; additionally, bundle-arranged mesenchymal cells that were only observed in the neonates on days 1-12 reacted strongly to α-SMA, but faintly to Thy-1. Blastemal cell-derived mesenchymal cells seem to alter the immunoexpressions of Thy-1 and α-SMA, depending on the conditions which they develop. Thy-1 immunoexpression would be useful for investigation of reverse embryogenesis, which might occur in fibrotic kidneys.  相似文献   
89.
Mouse monoclonal antibody c 143 was purified and F(ab')2 fragments were generated by pepsin digestion and then radiolabeled with 125I. The 125I-labeled c 143 F(ab')2 fragments were injected into athymic mice bearing bovine lymphoid tumor cells. The fragments became preferentially localized in tumor tissues, but not in normal tissues, as determined by differential counting of tissue radioactivity. The fragments became localized specifically in those tumors that were reactive with c 143 in vitro, but did not become localized in unrelated tumors. Localization of labeled F(ab')2 fragments of a monoclonal antibody of the same isotype directed against Taka virus (a variant of Newcastle disease virus) was not observed in athymic mice bearing bovine lymphoid tumor cells. Tumors were detectable by radioimmunoscintigraphy, using radiolabeled c 143 F(ab')2 fragments, without background subtraction, and by use of silver-grain scattering in light microscopic autoradiography.  相似文献   
90.
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