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In many brain areas, few cholinergic synapses are identified. Acetylcholine is released into the extracellular space and acts through diffuse transmission. Motoneurons, however, are contacted by numerous cholinergic terminals, indicating synaptic cholinergic transmission on them. The muscarinic m2 receptor is the major acetylcholine receptor subtype of motoneurons; therefore, we analyzed the localization of the m2 receptor in correlation with synapses by electron microscopic immunohistochemistry in the mouse trigeminal, facial, and hypoglossal motor nuclei. In all nuclei, m2 receptors were localized at the membrane of motoneuronal perikarya and dendrites. The m2 receptors were concentrated at cholinergic synapses located on the perikarya and most proximal dendrites. However, m2 receptors at cholinergic synapses represented only a minority (<10%) of surface m2 receptors. The m2 receptors were also enriched at glutamatergic synapses in both motoneuronal perikarya and dendrites. A relatively large proportion (20–30%) of plasma membrane–associated m2 receptors were located at glutamatergic synapses. In conclusion, the effect of acetylcholine on motoneuron populations might be mediated through a synaptic as well as diffuse type of transmission. J. Comp. Neurol. 521:2008–2024, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
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ABSTRACT

Background: Ginkgo biloba leaves extract has been widely used worldwide to protect against oxidative stress-induced cell damage and improves blood circulation. Methods: The potential protective role of the standardized leaf extract of Ginkgo biloba (EGb761) on hypertension-induced renal injury was investigated in rats. Hypertension was induced in rats by L-NAME. Result: Repeated treatment with EGb761 produced progressive reductions in the systolic, diastolic and mean arterial blood pressure. Also, EGb761 increased the progressive reductions in blood pressure induced by losartan. Hypertension-induced marked elevation of renal malondialdehyde (MDA) and nitrite levels and reduction of reduced glutathione (GSH) level were inhibited by EGb761. In addition, hypertension-induced increases in tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β)) levels in renal tissues were inhibited by EGb761. Also, treatment with EGb761 inhibited hypertension-induced decrease in endothelial nitric oxide synthase (eNOS) protein expression and increase in the protein expressions of inducible NO synthase (iNOS), TNF-α, IL-6 and IL-1B in the kidney tissues. EGb761 enhanced losartan effects on renal tissues oxidative stress, nitrite, and inflammatory markers levels and on protein expressions of eNOS, iNOS, TNF-α, IL-6 and IL-1B. effects. Conclusions:These results indicate that EGb761 has the ability to protect against hypertension-induced renal injury.  相似文献   
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The etiology of achalasia is believed to be the neuropathy associated with chronic inflammation of the nerve plexus, but the cause of plexus inflammation is unknown. The purpose of this study was to evaluate the pathophysiology of achalasia by examining the muscularis externa of the esophagus. We used the muscularis externa of the esophagus of 62 patients with achalasia (median 44 years, male : female 32:30) who underwent surgical treatment (achalasia group) and of 10 patients (median 65.5 years, male : female 9:1) who underwent esophagectomy for thoracic esophageal cancer (control group) to perform immunohistochemical staining with S‐100, CD43, c‐kit (CD117), n‐NOS, vasoactive intestinal polypeptide (VIP), and ubiquitin. The cell counts that were positive for S‐100, n‐NOS, VIP, and ubiquitin were significantly lower in the achalasia group compared with the control group (P < 0.001, P= 0.001, P < 0.001, and P= 0.001, respectively). There were no statistically significant differences with respect to CD43 and c‐kit staining (P= 0.586 and P= 0.209, respectively). In conclusion, the pathophysiology of achalasia is therefore considered to be an impaired production of NO and VIP, which both affect interstitial cell of Cajal and smooth muscles, and this impairment is therefore considered to play a role in the pathophysiology of achalasia.  相似文献   
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This is the first part of a 3‐part comprehensive review of intraosseous carcinoma of the jaws. We have outlined 4 groups of intraosseous carcinoma of the jaws (metastatic, salivary‐type, odontogenic, and primary intraosseous carcinoma), emphasizing the need for accurate diagnosis and the problems associated with changing classification systems, standardization of diagnostic criteria and nomenclature, and the accuracy of existing literature. In this first part, the features of metastatic and the very rare salivary‐type carcinomas of the jaws are examined with particular emphasis on histologic and immunohistochemical characteristics, diagnostic difficulties, and uncertainties. © 2012 Wiley Periodicals, Inc. Head Neck, 2012  相似文献   
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Oncotype DX has been criticized for not providing significantly more prognostic information than histopathologic analysis. Oncotype DX was validated in cohorts that included poor prognostic factors (HER2‐positive, low‐estrogen receptor [ER] expression), raising the question: if patients with known high recurrence rates are excluded, is the Recurrence Score (RS) still valid? Our purpose was to determine if RS can be predicted with readily available measures. One hundred and twenty samples from August 2006 to November 2010 that underwent Oncotype DX testing were analyzed. Data included RS, ER, progesterone receptor (PR), HER2, and Ki67 status by immunohistochemistry (IHC). IHC data were used to create two linear regression models to predict RS. SAS's JMP‐7 was used for statistical analysis. When comparing Oncotype DX‐ and IHC‐derived ER and PR values, there were 21 discordant samples. The linear regression model PRS‐F created with IHC data (ER, PR, HER2, Ki67) from all samples (= 120) had an adjusted R2 = 0.60 indicating a good model for predicting RS. The PRS‐R model was built without low‐ER and HER2‐positive samples (= 110). It had an adjusted R2 = 0.38 indicating poor prediction of RS. Oncotype DX data showed good concordance with IHC for ER‐ and PR‐expression in this cohort. Low‐ER samples had high RS. After removing low‐ER and HER2‐positives, calculating RS with PRS‐R from remaining data showed poor predictive power for RS (adjusted R2 = 0.38). This result questions whether RS is prognostic in this subgroup (who would most benefit from further clarification of recurrence risk) and independent of pathology, or is simply producing random RS values. Data bases available to Genomic Health can resolve this issue.  相似文献   
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目的:探讨干扰素-α诱导蛋白27(IFI27)在胰腺癌组织中的表达情况及其临床意义。方法:免疫组织化学法检测IFI27蛋白在胰腺癌、癌旁及慢性胰腺炎组织中的表达情况,分析阳性表达与胰腺癌患者相关临床病理参数和预后的关系。利用生物信息学方法基于TCGA数据库分析IFI27在胰腺癌组织中的表达差异和预后相关性。结果:IFI27在胰腺癌组织中表达的阳性率高于癌旁以及慢性胰腺炎组织(P<0.05),且与血管侵犯、淋巴结转移以及肿瘤分化程度相关。胰腺癌患者的总体生存期与肿瘤分化程度、血管侵犯、淋巴结转移以及IFI27阳性表达相关。多因素分析显示IFI27阳性表达是胰腺癌患者预后的独立危险因素。基于TCGA数据库分析得出IFI27在胰腺癌组织中的表达量高于正常组织(P<0.05),生存曲线提示IFI27低表达患者的预后优于高表达患者(P<0.05)。结论:IFI27高表达的胰腺癌患者预后差,IFI27阳性表达是胰腺癌患者的独立预后指标。  相似文献   
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