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91.
Seventeen patients who had undergone extensive small bowel resection were studied for calcium absorption (FACa) and plasma vitamin D metabolites. FACa was measured by a double radio-tracer technique and expressed as percentage of total oral dose. FACa was decreased compared with controls (34%, range: 3-46 v 65%, range: 57-73, P less than 0.01). A positive correlation (r = 0.49, P = 0.05) was found between FACa and the remaining length of small bowel (SBL). As wide variations in both SBL and duration after surgery were observed among the seventeen investigated patients, we were led to individualize less heterogeneous subgroups of patients. Better correlations were found when the patients were divided into two subgroups according to whether the time interval between the resection and the investigation was shorter (r = 0.75, n = 11, P less than 0.02) or longer (r = 0.89, n = 6, P = 0.05) than 2 years. In thirteen patients who had a SBL shorter than 100 cm, a positive correlation was observed between FACa and the time interval after surgery (months): r = 0.65, P less than 0.05. Plasma 1,25 (OH)2D was markedly reduced in the whole group (31 pmol l-1, range: 8-108) compared with controls (103 pmol-1, range: 59-134, P less than 0.01). The present study shows that in extensively small bowel resected patients, calcium absorption is reduced, the alteration being dependent both on the length of the remnant small bowel and on the time after surgery.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
92.
Using a sandwich enzyme-linked immunoassay, plasma total cathepsin D concentration was assayed in 40 breast cancer patients and 84 patients with various liver diseases and compared to that of 52 normal subjects. There were no significant variations found in breast cancer patients related to tumor size, node invasiveness or metastases. In normal women, cathepsin D levels were slightly but not significantly increased in the luteal phase and in pregnancy. By contrast, plasma cathepsin D concentration was significantly increased in 70-75% of patients with liver disease (cirrhosis, hepatocarcinoma, hepatitis), but not in those with liver steatosis. Cathepsin D was independent of most of the plasma hepatic function tests and was correlated with alpha-fetoprotein in cirrhosis and with alpha-fucosidase in primary hepatocellular carcinoma. We conclude that plasma cathepsin D is not a useful marker in breast cancer. However, since the cellular level of this protease is associated with risk of metastasis in breast cancer, clinical follow-up will be required to test whether high cathepsin D plasma concentration has any prognostic value in liver cirrhosis and primary hepatocarcinoma.  相似文献   
93.
Vitamin A (retinol), a fat-soluble vitamin, is an essential nutrient for the normal functioning of the visual system, epithelial cell integrity and growth, immunity, and reproduction. Our group has investigated the effect of high doses of oral vitamin A on early childhood diarrhea in our prospective community-based studies from Northeast Brazil and found a beneficial role in reducing the mean duration but not incidence of diarrheal episodes. In this study, we explored the role of retinol supplementation in intestinal cell lines following Clostridium difficile toxin A (TxA) challenge. C. difficile is the most common anaerobic pathogen borne with antibiotic-borne diarrhea and pseudomembranous colitis. Since retinol is critical for the integrity of tight junctions and to modulate the cell cycle, we have focused on changes in transepithelial electrical resistance (TEER) in Caco-2, a more differentiated intestinal cell line, and on models of cell proliferation, migration and viability in IEC-6 cells, an undifferentiated crypt cell line, following TxA injury. In this model, retinol therapy reduced apoptosis, improved cell migration and proliferation, and prevented the reduction in TEER, following C. difficile TxA challenge in a glutamine-free medium. These results suggest the role of retinol in protecting intestinal epithelial barrier function from C. difficile TxA enterotoxic damage.  相似文献   
94.
制作缺血性中风气虚血瘀证大鼠模型的实验研究   总被引:3,自引:0,他引:3  
目的 探索建立缺血性中风气虚血瘀证大鼠模型的制作方法和评价体系。  相似文献   
95.
缩泉丸对肾阳虚多尿大鼠内分泌及免疫功能的影响   总被引:4,自引:0,他引:4  
目的 观察缩泉丸对肾阳虚多尿模型大鼠内分泌及免疫功能的影响.方法 用腺嘌呤250 mg/kg灌服大鼠4周,造成肾阳虚多尿模型,分别给予缩泉丸、肾气丸和去氨加压素(dDAVP)治疗4周,检测缩泉丸对体重、脏器系数、血清中皮质酮浓度和外周血T淋巴细胞亚群水平的影响.结果 模型组大鼠体重比正常对照组大鼠明显降低,dDAVP组、缩泉丸中、高剂量组与模型组大鼠体重相比,具有显著性差异(P<0.05或P<0.01).与正常对照组比较,模型组大鼠胸腺、肾上腺和垂体系数明显降低(P<0.05或P<0.01);与模型组比较,除缩泉丸低剂量组外,其余各治疗组的胸腺系数均明显提高,差异具有显著性(P<0.05);与模型组比较,垂体和肾上腺系数,仅在肾气丸组和缩泉丸高剂量组发现有明显提高,差异具有显著性(P<0.05).模型组具有较低的血清中皮质酮浓度,与正常对照组比较,具有非常显著性差异(P<0.01),肾气丸组和缩泉丸中、高剂量组血清中皮质酮浓度比模型组明显增加,具有显著性差异(P<0.05或P<0.01).与正常对照组比较,肾阳虚多尿模型组大鼠外周血T淋巴细胞CD3+百分比、CD3+/CD4+百分比明显减少,CD3+/CD8+百分比明显增加,差异具有显著性(P<0.05或P<0.01);与模型组比较,肾气丸组和缩泉丸低、中、高剂量组CD3+百分比、CD3+/CD4+百分比明显增加,CD3+/CD8+百分比明显减少,差异具有显著性,与模型组相比dDAVP组CD3+百分比、CD3+/CD4+百分比和CD3+/CD8+百分比均无显著性差异.结论 缩泉丸能够调节肾阳虚多尿大鼠的内分泌及免疫功能.  相似文献   
96.
目的 评价诊断中老年男子部分雄激素缺乏综合征(PADAM)的游离睾酮指数(FTI).方法 对129例45岁以上健康男性的FTI进行年龄相关分析.以推算的游离睾酮(CFT)值为依据,对FTI进行有效性检验.结果 男子在中老年期FTI与增龄呈明显的负相关.FTI敏感性97.78%,特异性58.33%.结论 计算简单的FTI可用于PADAM病人的筛选和随访,尤其对70岁以上男子是血清FT较为有效的参数.  相似文献   
97.
目的:检测胰腺癌及癌旁组织中Pin1和周期素D1基因的表达,探讨Pin1在胰腺癌发病中所起的作用。方法:收集27例胰腺肿瘤组织及其相应的肿瘤旁组织标本,采用实时荧光定量逆转录聚合酶链反应法(RQ RT-PCR)检测胰腺良恶性肿瘤及肿瘤旁组织中Pin1和周期素D1 mRNA 的表达,运用Fisher精确概率分析两者之间的相关性及其与肿瘤临床分期和病理特征的关系。结果:7例胰腺囊腺瘤中周期素D1和Pin1的表达与肿瘤旁组织之间无显著性差异;而20例胰腺癌中周期素D1和Pin1的表达明显高于肿瘤旁组织[(2.78±1.02)vs.(4.36±1.27)和(5.48±1.69) vs. (9.97±1.86),P<0.05)]。Pin1和周期素D1与肿瘤的临床分期和病理分化程度无明显的相关(组间差异均为P>0.05),但Pin1与周期素D1的表达有关(P<0.01)。 结论:胰腺癌中Pin1的过表达可促进周期素D1表达,由此诱导了肿瘤的发生;Pin1可能在胰腺癌中起着重要作用。  相似文献   
98.
肠易激综合征(IBS)是一组持续存在或反复发作的临床症候群,主要症状有腹痛、腹胀、排便习惯改变和大便性状异常、黏液便等,经检查排除可引起这些症状的器质性疾病。临床分为肝木乘脾型腹泻、脾胃虚弱型腹泻、脾肾阳虚型腹泻、肝郁脾虚型便秘四型,根据临床辨证分别施以不同治法,不同方药治疗,有显著疗效。同时,教育患者平时养成良好的饮食卫生习惯,不饮生水,不食生冷瓜果,忌食辛辣、油腻、肥厚之品,保持心情舒畅,怡情悦志,注意保暖,可加强疗效,防止复发。  相似文献   
99.
Iron deficiency (ID) is one of the most commonly known forms of nutritional deficiencies. Low body iron is thought to induce neurologic defects but may also play a protective role against cancer development by cell growth arrest. Thus, ID may affect cellular pathways controlling cell growth and proliferation, the mechanism of which is still not fully understood. The serine/threonine protein kinase Akt and its downstream target, the mammalian Target of Rapamycin (mTOR), is known to play a crucial role in the regulation of cell growth and survival. Therefore, we hypothesized that Akt/mTOR pathway could be influenced by ID. Three-week-old male Wistar-strain rats were divided into 3 groups and the 2 groups had free access to a control diet (C group) or an iron-deficient diet (D group). The third group (PF group) were pair-fed the control diet to the mean intake of the D group. After 4 weeks, rats were killed and their brains were sampled. In separate experiments, COS-1 cells were cultured with or without the iron chelator deferoxamine. Western blots of brain samples and COS-1 lysates were used to analyze the expression and phosphorylation state of Akt, TSC2, mTOR, and S6 kinase proteins implicated in the Akt/mTOR pathway. Using 2 different ID models, we show for the first time that iron deficiency depresses Akt activity in rats and in COS-1 cells, leading to a decrease in mTOR activity.  相似文献   
100.
邻近皮瓣修复面部皮肤缺损   总被引:1,自引:0,他引:1  
目的 探讨邻近皮瓣修复面部皮肤缺损的应用效果。方法 162例面部病变切除后皮肤缺损患者,其中先天性色素痣63例,基底细胞癌28例,鳞状细胞癌6例,其他皮肤病变65例。均采用邻近皮瓣即时修复,其中菱形皮瓣57例、双叶皮瓣8例,A-T皮瓣23例、V-Y皮瓣13例、Z成形术23例、推进皮瓣27例、鼻状皮瓣11例。结果 162例皮瓣存活良好,手术切口1期愈合,存活后皮瓣颜色与邻近部位无明显差异,术后无眼睑、眉毛、鼻梁及口角牵扯歪钭,术后3个月切口不显露。结论 邻近皮瓣是修复面部较大皮肤缺损的良好方法,手术外观效果好。  相似文献   
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