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41.
547例垂体腺瘤延迟诊断原因及影像诊断分析   总被引:2,自引:0,他引:2  
目的:提高垂体腺瘤特别是微腺瘤早期影像诊断率。方法:通过对所搜集病史资料完整,经医学影像学确诊和手术病理证实的547例垂体腺瘤(内有251例微腺瘤)延迟诊断原因的分析,找到影响垂体腺瘤早期诊断的因素。结果:296例垂体大腺瘤蝶鞍X线平片、CT、MR常规检查即可诊断。CT骨窗蝶鞍片有助于垂体微腺瘤的诊断,251例微腺瘤经高分辨力CT薄层冠状强化扫描和高场强MR薄层强化扫描得以明确诊断。结论:熟悉垂体腺瘤的首发症状,及时行CT、MR常规扫描可明确大腺瘤的诊断,CT骨窗片可发现垂体微腺瘤的佐证。高场强MR薄层强化扫描是目前诊断垂体微腺瘤的最佳方法,高分辨力CT冠状薄层强化扫描次之,结合神经内分泌学检查是提高垂体腺瘤影像学早期诊断率的主要措施。  相似文献   
42.
Regulation of erythropoietin production   总被引:6,自引:0,他引:6  
  相似文献   
43.
目的:探讨不同方案治疗早期糖尿病视网膜病变的经济效果,找出既经济又有效的方案。方法:对目前临床常用的4种不同治疗方案(导升明、胰激肽原酶、复方血栓通胶囊、复方丹参滴丸,治疗时间均为90d)运用药物经济学方法进行成本-效果分析。结果:4种方案所需费用分别为1417.50元、810.00元、891.00元、656.10元;治疗有效率分别为94.25%、85.09%、85.17%、83.53%;成本-效果比分别为15.04、9.52、10.46、7.85。结论:复方丹参滴丸治疗效果较好,不良反应少,成本低廉。  相似文献   
44.
BACKGROUND: Abnormal glucose tolerance is a frequent co-morbidity in cystic fibrosis patients (CF), and is associated with a worse prognosis. The objectives are to investigate (a) the relative contribution of insulinopenia and insulin resistance (IR) for glucose tolerance and (b) the association between various glucose parameters and CF clinical status. METHODS: Oral glucose tolerance tests were performed in 114 consecutive CF patients not known to be diabetic as well as 14 controls similar for age and BMI. RESULTS: Abnormal glucose tolerance was found in 40% of patients with CF: 28% had impaired glucose tolerance (IGT) and 12% had new cystic fibrosis related diabetes (CFRD). Compared to control subjects, all CF patients were characterized by an increased glucose excursion (AUC). While reduced early insulin release characterised CF, IGT and CFRD patients also present IR thus both mechanisms significantly contribute to glucose tolerance abnormalities. Increased glucose AUC and reduced early insulin release but not glucose tolerance categories were associated with a reduced pulmonary function (FEV(1)). CONCLUSION: In CF, early insulin secretion defect but also IR contribute to glucose intolerance. Early in the course of the disease, increased glucose AUC and reduced early insulin secretion are more closely associated with a worse clinical status than conventional glucose tolerance categories.  相似文献   
45.
市场机制下政府调节与医疗管制制度框架的构建   总被引:4,自引:1,他引:3  
医疗机构分类管理的政策确定了我国医疗服务的市场取向.我国医疗市场服务因其特殊的技术经济特点也存在一般意义上的市场失灵,使政府管制这一非市场治理机制的产生与存在成为必要,以弥补与矫正市场缺陷,保证医疗服务市场的规范运行和卫生改革的顺利推进.  相似文献   
46.
The binary opposition of trusting or not trusting is inadequate to understand the often ambiguous and contradictory ideas people possess about risk regulators, particularly when knowledge and experience of such institutions is limited. The paper reports qualitative and quantitative data from a major study of public perceptions (n?=?30 focus groups) of UK risk regulators. We compare the complex and widely different ‘trust profiles’ of two regulatory organisations which are institutionally related (the Health and Safety Executive and the Railways Inspectorate) but very separate in the minds of our participants. The paper develops the notion of critical trust to interrogate the various ways in which people make sense of such organisations, as well as discussing the modes of reasoning that people deploy. The paper argues that views of participants are the outcome of a reconciliation of diverse perceptions concerning the role of the organisation, structural factors and the nature of the regulated risk.  相似文献   
47.
总结胸腹轴型皮瓣早期修复上肢不同部位的深度蛇伤溃疡的经验,评价其应用价值。本组16例,胸脐皮瓣2例,侧胸腹皮瓣1例,髂腰皮瓣5例,下腹皮瓣6例,下腹分叶皮瓣1例,髂腰加下腹Y形皮瓣1例。术后1例皮瓣远端坏死,3例轻度感染,16例断蒂后全部成活。随访3个月~7年,皮瓣质地和弹性均好,手功能基本恢复。认为,带蒂胸腹轴型皮瓣是修复上肢深度蛇伤溃疡理想的方法。  相似文献   
48.
We wanted to clarify whether the postprandial intestinal feedback control activated by nutrients in the distal gut exerts different effects on motility, transit of digesta, and absorption of nutrients in the proximal gut. Additionally, interrelationships among motility, transit, and absorption were to be elucidated because these relationships have only been investigated in the fasted state. In five minipigs, a 150-cm segment of the proximal jejunum was isolated by two cannulas. Motility of the jejunal segment was recorded by multiple strain gauges and analyzed by computerized methods. Markers (Cr- and Cu-EDTA) were used for the measurement of the flow rate, transit time, and absorption of nutrients. After a meal, the test segment was perfused with 2 kcal/min of an elemental diet over a period of 90 min. A feedback inhibition was activated by infusion of nutrients into the midgut at rates of 1–4 kcal/min. Saline was infused as control. With increasing energy loads infused into the midgut, the motility index and the length of contraction waves decreased, whereas the incidence of stationary contractions increased, ie, the motility changed from a propulsive to a segmenting pattern. These modulations of motility were associated with a linear decrease in the flow rate and a linear increase in transit time. Flow and transit were linearly correlated with each other. Additionally, the reduction in flow rate and the delay in luminal transit were associated with a linear increase in the absorption of nutrients. However, the increase in absorption induced by the feedback mechanism was small (7.3–13.4%) compared to the marked inhibition of the motility parameters (54–64%), the flow rate (59%), and the delay of transit (5.8-fold). Feedback control primarily modulated motor patterns and luminal flow, whereas the small increase in absorption was only a side effect due to the longer contact time of the nutrients with the mucosa.The study was supported by the Deutsche Forschungsgemeinschaft, grant Eh 64/6-3.  相似文献   
49.
50.
The in vitro capacity of sympathetic superior cervical ganglia (SCG) to take up [3H]choline from the extracellular medium, to synthesize acetylcholine from [3H]choline, and to release [3H]acetylcholine in response to a high K+ concentration, were examined in rats throughout a 24-h cycle. Both the release of [3H]acetylcholine and the synthesis of [3H]acetylcholine from [3H]choline exhibited significant diurnal variations, showing maxima during the first half of the night. After these maxima, nocturnal acetylcholine release and synthesis decayed to daytime levels and remained low until the end of the night. [3H]Choline uptake by rat SCG did not vary significantly throughout a 24-h period. A 1.5-h exposure of rats to darkness at the 5th hour of light phase of the daily photoperiod did not change significantly any parameter studied. A 20-min, 5-Hz, electrical stimulation of the preganglionic trunk of SCG excised from rats at noon increased significantly subsequent K+-induced [3H]acetylcholine release but did not change [3H]acetylcholine synthesis. In decentralized SCG of rats subjected to a unilateral SCG decentralization and a contralateral sham-operation 7 days earlier, [3H]acetylcholine release and synthesis were highly reduced or abolished at the decentralized side, while [3H]choline uptake remained unaltered. The present results suggest that an activation of preganglionic rat SCG neurons takes place during the first half of the scotophase.  相似文献   
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