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181.
目的:探讨皮质醇增多症的临床表现和内分泌检查等辅助检查的意义.方法:从年龄、性别、病程及实验室检查等方面,观察22例不同原因所致皮质醇增多症患者不同的临床表现和测定实验室检查指标.结果:22例中诊断库欣病(增生型)14例[63.6%,其中13例(92.9%)得到MRI检查证实],肾上腺腺瘤6例[27.3%,均得到MRI检查证实(100%)],另有肾上腺结节样增生1例(4.5%),异位ACTH综合征1例(4.5%).临床表现:按出现的频率前4位依次为,库欣病:高血压(100%)、满月脸(92.9%)、向心性肥胖(85.7%)、多血质(85.7%),肾上腺腺瘤:高血压(100%)、满月脸(100%)、向心性肥胖(100%)、多血质(83.3%).实验室检查:小剂量地塞米松不能抑制:库欣病与肾上腺腺瘤均为100%.结论:根据高血压、满月脸、向心性肥胖,小剂量地塞米松抑制试验和MRI检查可诊断绝大多数皮质醇增多症.  相似文献   
182.
Platelet Endothelial Cell Adhesion Molecule 1 (PECAM-1) deficient mice in the FVB/n strain exhibit fatal chronic pulmonary fibrotic disease. The illness occurs in the absence of a detectable pro-inflammatory event. PECAM-1 is vital to the stability of vascular permeability, leukocyte extravasation, clotting of platelets, and clearance of apoptotic cells. We show here that the spontaneous development of fibrotic disease in PECAM-1 deficient FVB/n mice is characterized by early loss of vascular integrity in pulmonary capillaries, resulting in spontaneous microbleeds. Hemosiderin-positive macrophages were found in interstitial spaces and bronchoalveolar lavage (BAL) fluid in relatively healthy animals. We also observed a gradually increasing presence of hemosiderin-positive macrophages and fibrin deposition in the advanced stages of disease, corresponding to the accumulation of collagen, IL-10 expression, and myofibroblasts expressing alpha smooth muscle actin (SMA). Together with the growing evidence that pulmonary microbleeds and coagulation play an active part in human pulmonary fibrosis, this data further supports our hypothesis that PECAM-1 expression is necessary for vascular barrier function control and regulation of homeostasis specifically, in the pulmonary environment.  相似文献   
183.
Tic severity is composed of several dimensions. Tic frequency and intensity are two such dimensions, but little empirical data exist regarding their relative contributions to functional impairment in those with chronic tic disorders (CTD). The present study examined the relative contributions of these dimensions in predicting tic-related impairment across several psychosocial domains. Using data collected from parents of youth with CTD, multivariate regression analyses revealed that both tic frequency and intensity predicted tic-related impairment in several areas; including family and peer relationships, school interference, and social endeavors, even when controlling for the presence of comorbid anxiety symptoms and Attention Deficit Hyperactivity Disorder diagnostic status. Results showed that tic intensity predicted more variance across more domains than tic frequency.  相似文献   
184.
Apolipoprotein A-IV (apoA-IV) is secreted by the small intestine in response to fat absorption. Here we demonstrate a potential role for apoA-IV in regulating glucose homeostasis. ApoA-IV-treated isolated pancreatic islets had enhanced insulin secretion under conditions of high glucose but not of low glucose, suggesting a direct effect of apoA-IV to enhance glucose-stimulated insulin release. This enhancement involves cAMP at a level distal to Ca(2+) influx into the β cells. Knockout of apoA-IV results in compromised insulin secretion and impaired glucose tolerance compared with WT mice. Challenging apoA-IV(-/-) mice with a high-fat diet led to fasting hyperglycemia and more severe glucose intolerance associated with defective insulin secretion than occurred in WT mice. Administration of exogenous apoA-IV to apoA-IV(-/-) mice improved glucose tolerance by enhancing insulin secretion in mice fed either chow or a high-fat diet. Finally, we demonstrate that exogenous apoA-IV injection decreases blood glucose levels and stimulates a transient increase in insulin secretion in KKAy diabetic mice. These results suggest that apoA-IV may provide a therapeutic target for the regulation of glucose-stimulated insulin secretion and treatment of diabetes.  相似文献   
185.

Background and Aim

Negative association has been reported between presence of Helicobacter pylori and developing gastroesophageal reflux disease (GERD) and its complications. The aim of this study was to determine whether H. pylori (HP) can be protective against GERD in an African American (AA) population.

Methods

From 2004 to 2007, we studied 2,020 cases; esophagitis (58), gastritis (1,558), both esophagitis and gastritis (363) and a normal control group (41). We collected their pathology and endoscopy unit reports. HP status was determined based on staining of gastric biopsy.

Results

HP data was available for 79 % (1,611) of the cases. The frequency of HP positivity in gastritis patients was 40 % (506), in esophagitis patients 4 % and in normal controls 34 % (11), while HP was positive in 34 % of the patients with both esophagitis and gastritis. After adjusting for effects of age and sex, odds ratio of HP was 0.06 (95 % CI 0.01–0.59; P value = 0.01) for the esophagitis group versus the normal group.

Conclusions

Our results show H. pylori has a significant negative association with esophagitis in AAs which may point to a protective role of H. pylori in the pathogenesis of esophagitis. In addition, H. pylori may be the reason for the low GERD complications in AAs.  相似文献   
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187.
Abstract. To determine whether West Nile virus (WNV) persistent infection in avian hosts may potentially serve as an overwintering mechanism, House Sparrows and House Finches, experimentally and naturally infected with several strains of WNV, and two naturally infected Western Scrub-Jays were held in mosquito-proof outdoor aviaries from 2007-March 2008. Overall, 94% (n = 36) of House Sparrows, 100% (n = 14) of House Finches and 2 Western Scrub-Jays remained WNV antibody positive. When combined by species, 37% of the House Sparrows, 50% of the House Finches, and 2 Western Scrub-Jays were WNV RNA positive at necropsy, up to 36 weeks post-infection. Infectious WNV was not detected. Our study supports the hypothesis that some avian hosts support the long-term persistence of WNV RNA, but it remains unresolved whether these infections relapse to restart an avian-arthropod transmission cycle and thereby serve as an overwintering mechanism for WNV.  相似文献   
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