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31.
Dyspepsiareferstopainordiscomfortfo cusedintheepigastrium,whichwasreportedtooccurinmorethan 1 0 %ofoutpatientsininternalmedicine,andnearlyhalfthepatientsinthegas trointestinal(GI)department(1).Almosthalfofthesepatientswithdyspepsiawhohavenodefi niteorgani…  相似文献   
32.
PTH has diverse effects on bone metabolism: anabolic when given intermittently, catabolic when given continuously. The cellular mechanisms underlying the varying target cell response are not clear yet. PTH induces RGS-2, a member of the Regulator of G-protein Signaling protein family, via cAMP/PKA, and inactivates PKC-mediated signaling. To investigate intracellular signaling pathways with different PTH concentration-time patterns, we treated UMR 106-01 osteoblast-like cells in a perfusion system. PTH was administered intermittently (4 min/h, 10−7 M) or continuously at an equivalent cumulative dose (6.6 × 10−9 M). cAMP was measured using radioimmunoassay, mRNA levels using real-time rtPCR and ribonuclease protection assay, and protein levels using Western immunoblotting. A single PTH pulse transiently increased cAMP levels by 2000% ± 1200%. In contrast to continuous PTH exposure, cAMP induction remained unchanged with intermittent PTH, ruling out desensitization of the PTH receptor. In continuously perfused cells, RGS-2 abundance was three to five times higher than in cells intermittently exposed to PTH for up to 12 h. MKP-1 and -3 were significantly less induced with pulsatile PTH; exposure-mode-dependent differences in MMP-13 and IGFBP-5 were small. Pulsatile but not continuous PTH administration prevents PTHrP receptor desensitization and accumulation of RGS-2 in osteoblasts, which should preserve PKC-dependent signaling.  相似文献   
33.
[目的]探讨一氧化氮在激素性股骨头坏死发病中的作用.[方法]制作激素性股骨头坏死家兔模型后,在不同时期测定血浆及软骨中的一氧化氮含量,观察股骨头的组织学变化.[结果]激素性股骨头坏死家兔血浆和软骨中的一氧化氮含量均明显升高,股骨头髓腔中的脂肪细胞明显增多,骨小梁变细、稀疏及断裂,空骨陷窝明显增多.电子显微镜观察见骨细胞核染色质浓缩,体积缩小,胞浆中内质网及线粒体肿胀变性,粗面内质网上的核糖体脱落.[结论]一氧化氮参与激素性股骨头坏死的发病过程.  相似文献   
34.
Chronic intestinal pseudo-obstruction (CIPO) is a rare pathological condition characterized by a marked derangement of gut propulsive motility mimicking mechanical obstruction, in the absence of any lesion occluding the gut lumen. This disease is often associated with a disabling and potentially life-threatening complications and is still too often unrecognized even in referral centres. As a result, patients receive neither appropriate care nor recognition of their severe health condition. Medical and surgical therapies are often unsatisfactory and long-term outcome turns out to be poor in the vast majority of cases. This article focuses on the main clinical features, the management and long-term outcome of patients affected by CIPO, with particular emphasis on those aspects which remain a matter of debate.  相似文献   
35.
The purpose of the study was to attempt to replicate a finding of Persky et al. (1978) that midcycle peak values of testosterone (T) in women predicted differences in frequency of intercourse among married couples. Luteinizing hormone (LH), total testosterone (TT), and free testosterone (FT) values from 10 to 14 daily midcycle blood samples donated by 43 volunteering wives were analyzed against sexual activity patterns reported by the couples over a longer period of time. All couples were contracepting by means other than exogenous hormones or the rhythm method. Each morning through three menstrual cycles husbands and wives recorded independently and on separate forms answers to a series of questions concerning sexual activity in the previous 24 hr. Wives also recorded basal body temperatures (BBT). We designated midcycle values of TT and FT according to several definitions of midcycle. Total testosterone levels at the day of the BBT nadir and the day before the nadir correlated significantly with average intercourse frequency. Correlations with FT were statistically significant regardless of which midcycle measure was used; the day before the BBT nadir gave the highest correlation, 0.618, p = 0.01. Mean testosterone (TT or FT) values were not significantly related. We conclude that female midcycle total testosterone or free testosterone is indexing some unobserved event that affects the frequency of intercourse of couples. We speculate that this event affects the motivation of females, which influences the set point of the compromise frequency characteristic of couples.Research supported in part by NICHD Grant No. 1-R01-HDO7454-01.  相似文献   
36.
This is a retrospective review of the results at our institution of using multi-detector CT angiography (CTA) to localise lower gastrointestinal (GI) bleeding. We hypothesised that in our patient population: (i) CTA was unlikely to demonstrate bleeding in patients who were haemodynamically stable; (ii) in haemodynamically unstable patients in whom CTA was undertaken, the results could be used to select patients who would benefit from catheter angiography; and (iii) in haemodynamically unstable patients in whom CTA was undertaken, a subgroup of patients could be identified who would benefit from primary surgical treatment, avoiding invasive angiography completely. A retrospective review was conducted of the clinical records of all patients undergoing CTA for lower GI haemorrhage at our institution between 1 January 2005 and 30 June 2007. Out of the 20 patients examined, 10 had positive CTAs demonstrating the bleeding site. Nine were haemodynamically unstable at the time of the study. Four patients with positive CT angiograms were able to be treated directly with surgery and avoided invasive angiography. Ten patients had negative CTAs. Four of these were haemodynamically unstable, six haemodynamically stable. Only one required intervention to secure haemostasis, the rest stopped spontaneously. No haemodynamically stable patient who had a negative CTA required intervention. CTA is a useful non-invasive technique for localising the site of lower GI bleeding. In our patient population, in the absence of haemodynamic instability, the diagnostic yield of CTA was low and bleeding was likely to stop spontaneously. In haemodynamically unstable patients, a positive CTA allowed patients to be triaged to surgery or angiography, whereas there was a strong association between a negative CTA and spontaneous cessation of bleeding.  相似文献   
37.
目的:探讨提高原发胃肠道淋巴瘤术前诊断率及治疗效果的方法。方法:对36例原发胃肠道淋巴瘤患者的临床表现、体征及辅助检查进行分析,通过COX回归等统计方法对其预后因素及生存率等进行分析。结果:该病临床表现无特异性;诊断主要依靠内窥镜病理活检;手术方式、综合治疗完成情况、临床分期为与预后有关的影响因素。结论:提高对该病临床表现及内镜、造影检查特点的认识,采用正确的活检方法是提高术前诊断率的关键;以手术及化疗为主的综合治疗措施是提高疗效的关键。  相似文献   
38.
目的:分析上消化道出血相关因素,制定预防和护理对策。方法:对120例上消化道出血病人相关因素进行总结分析,提出对策。结果:本病相关因素最多的分别是发病原因系十二指肠溃疡和胃溃疡;有发病诱因,主要是饮食不当、饮酒、药物和劳累;中青年、农村和农民发生率各占72.5%、69.17%和57.50%;中度出血35.00%;出血发生24小时后就诊68.33%。结论:本病应从个人、家庭、社会和早期诊治四方面预防,并通过系统护理,促进疾病康复。  相似文献   
39.
下消化道出血的少见病因   总被引:2,自引:0,他引:2  
下消化道出血病因复杂,随着诊疗技术的发展,人们对一些少见病因有了越来越多的了解,现就部分少见病因作一综述,以帮助临床诊断与治疗.  相似文献   
40.
鼻胃管胃肠减压在择期腹部手术中的应用价值   总被引:6,自引:0,他引:6  
鼻胃管胃肠减压曾被常规应用于择期和急诊的腹部手术后,目的是预防急性胃扩张的发生、治疗梗阻、降低吻合口压力等。但是,鼻胃管置入也会带来一些副作用,如呼吸道并发症、胃-食道反流、体液和电解质的丢失、声带的损伤,以及越来越被重视的患者的不适感。近年来的研究结果也对择期的腹部手术后常规应用鼻胃管胃肠减压提出不同的看法。现重新评价应用鼻胃管胃肠减压的理论基础及相关临床研究的结果,并对鼻胃管胃肠减压在择期腹部手术中的价值作一综述。  相似文献   
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