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The distribution of the neuronal form of nitric oxide synthase (bNOS) was investigated in the brain and pituitary gland of the catfish, Synodontis multipunctatus. Immunoreactive neurons were found mainly in the nucleus praeopticus periventricularis, the parvocellular and supraoptic subdivisions of the nucleus praeopticus, the nucleus recessus lateralis and the nucleus recessus posterioris. In addition, some scattered bNOS labeled somata were noted in the dorsal hypothalamic area. A few positive cells in the adenohypophysis and some reactive fibers in the pituitary stalk were also seen. Our results are compatible with the notion that the cells expressing bNOS in the diencephalon and hypophysis are involved in the control of hormone regulation. Moreover, the presence of bNOS positive cells in the rostral pars distalis of the pituitary gland supports a role of nitric oxide in osmoregulation.  相似文献   
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Over a two-year period, 100 venous angiograms were performed on 75 patients because of difficulty with vascular access. Seventy percent of the patients had decreased arterial flow or increased venous resistance. High output failure, sepsis, and aneurysm formation were also found. Venous angiography of the fistula demonstrated significant stenosis in 40% of the cases as well as total occlusion by thrombus in 9%, aneurysm formation in 7%, and abnormal fistula needle placement or anatomic abnormalities in 20% of the cases. Definitive diagnosis with the aid of venous angiography permitted specific surgical intervention in 62% of the cases, and identified new sites for needle placement in 18% of the cases, thus prolonging fistula life and reducing the need for new fistula placement. Our experience with local cellulitis of the fistula site and sepsis is also discussed.  相似文献   
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Despite the vast abundance of glial progenitor cells in the mouse brain parenchyma, little is known about the molecular mechanisms driving their proliferation in the adult. Here we unravel a critical role of the G1 cell cycle regulator cyclin D1 in controlling cell division of glial cells in the cortical grey matter. We detect cyclin D1 expression in Olig2‐immunopositive (Olig2+) oligodendrocyte progenitor cells, as well as in Iba1+ microglia and S100β+ astrocytes in cortices of 3‐month‐old mice. Analysis of cyclin D1‐deficient mice reveals a cell and stage‐specific molecular control of cell cycle progression in the various glial lineages. While proliferation of fast dividing Olig2+ cells at early postnatal stages becomes gradually dependent on cyclin D1, this particular G1 regulator is strictly required for the slow divisions of Olig2+/NG2+ oligodendrocyte progenitors in the adult cerebral cortex. Further, we find that the population of mature oligodendrocytes is markedly reduced in the absence of cyclin D1, leading to a significant decrease in the number of myelinated axons in both the prefrontal cortex and the corpus callosum of 8‐month‐old mutant mice. In contrast, the pool of Iba1+ cells is diminished already at postnatal day 3 in the absence of cyclin D1, while the number of S100β+ astrocytes remains unchanged in the mutant. GLIA 2014;62:829–839  相似文献   
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Occurring in China, DPR Korea, Japan, and Russian Federation and classified in the Red List of Chinese Flora as a vulnerable species, Rhodiola sachalinensis Boriss. is used increasingly in cosmetics, dietary supplements, and Traditional Chinese Medicines (TCMs). The aim of this study was to evaluate the (i) conservation status, harvesting and trade levels of R. sachalinensis,(ii) current state of experimental and commercial farming, and (iii) evidence of substitution or interchangeable use of R. sachalinensis with other Rhodiola species. We assessed data from multiple disciplines and languages including studies on R. sachalinensis biology and ecology, information on impacts of wild harvest, management measures, and current levels of cultivation. Our assessment shows that while R. sachalinensis is increasingly produced by cultivation, wild populations are decreasing and face multiple threats. These include (a) habitat loss including due to oil and gas infrastructure development on Sakhalin island,(b) climate change impacts on alpine ecosystems, and (c) overexploitation of wild plants to satisfy the growing commercial demand. Assessments of the conservation status of R. sachalinensis should commence in each Range State, as well as resource assessments and monitoring of harvesting and trade of wild R. sachalinensis. Even with increased reliance on cultivation, biodiversity conservation, and genetic diversity in wild populations are relevant to future use of this species.  相似文献   
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Introduction First-trimester screening according to Nicolaides uses maternal age to obtain a common background risk for trisomy 21. The likelihood ratios by nuchal translucency, free β-human chorionic gonadotropin and pregnancy-associated plasma protein-A are not with respect to maternal age. It was the aim of this study to investigate if likelihood ratios should better take care of it. Materials Pearson’s correlation and different models of regression analysis had been performed on the results of 8,116 first-trimester screenings. The total number of pregnancies was subdivided into three subgroups of healthy fetuses (n = 8,038); fetuses with Down’s syndrome (n = 46) and fetuses with other genetic abnormalities (n = 32). Statistical testing was applied to each of the three groups. Results Strong independence from maternal age could be found for each of the first-trimester screening measurement parameter, as well for healthy and as for affected fetuses. Neither Pearson’s test nor nonlinear regression models could detect a correlation. Accordingly significance of Pearson’s test is not given. Discussion First-trimester screening would not be improved by considering the maternal age in the calculation of the likelihood ratios. Therefore the currently used algorithm is adequate. According, to the results, it seems to be proper as well to disregard the maternal age in newer test strategies advanced first-trimester screening (AFS) at all.  相似文献   
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Background Fine-needle aspiration (FNA) is accurate in diagnosing papillary, medullary, and anaplastic thyroid cancer, as well as lymphoma. Although many surgeons routinely perform FNA before surgery, some question whether FNA influences operative management. Therefore, to determine whether FNA affects surgical management in patients with thyroid cancer, we reviewed our experience. Methods A total of 442 consecutive patients underwent thyroid surgery at 1 academic center. Of these, 411 had surgery for an index nodule in the absence of previous radiation or familial thyroid cancer. FNA, operative, and permanent histology findings were reviewed. Results The average patient age was 46 years, and 79% were female. A total of 211 patients (51%) had a preoperative FNA, and 71 (17%) had a final diagnosis of cancer. The sensitivity and specificity of FNA for thyroid cancer were 89% and 92%, respectively. In the FNA group, 1 (2.4%) of 41 patients with papillary thyroid cancer required completion thyroidectomy. In contrast, in the no-FNA group, 4 (40%) of 10 patients with papillary thyroid cancer required a second operation. No patient in the FNA group received thyroid resection for lymphoma, whereas three (100%) of three patients with lymphoma in the no-FNA group were treated surgically. A total of 98% of the FNA group, compared with 54% of the no-FNA group, received optimal surgical treatment for thyroid cancer. Conclusions FNA is a sensitive and specific test for the diagnosis of thyroid cancer, allowing definitive initial surgery and avoiding unnecessary procedures. Therefore, we recommend routine use of preoperative thyroid FNA, even in those patients in whom a resection is already planned. Presented at the 58th Annual Meeting of the Society of Surgical Oncology, Atlanta, Georgia, March 3–6, 2005.  相似文献   
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