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91.
目的 :研究皖北地区经输血传播病毒 (TTV)在血透患者中的感染。方法 :选TTVORF1的保守序列作内外引物 ,采用微板核酸杂交 -ELISA方法检测血透患者 6 0例及对照组血清标本中的TTV DNA。结果 :对照组和血透患者间TTV的阳性率差异显著 (P <0 0 5 ) ;TTV阳性和阴性的血透患者 ,在透析次数和透析时间方面有统计学意义 (P<0 0 5 )。结论 :皖北地区一般人群和血透患者中存在TTV感染 ,后者是TTV感染的高危人群。TTV可能与HBV ,HCV ,或HGV有类似的传播途径 ,主要经血液途径传播。  相似文献   
92.
运用轨道的有限单元模型,采用荷载增量法,计算了低温条件下大型养路机械维修超长无缝线路对钢轨应力和锁定轨温的影响。计算结果表明,大型机械在一次性起道时会对钢轨产生较大的应力,建议一次性起道量不超过40mm。  相似文献   
93.
A new generation of intelligent systems is growing up in the community of Artificial Intelligence in Medicine. The main goal of these systems is the representation and use of real theory of diseases, as they are represented in medical textbooks or in scientific articles, rather than the heuristic shortcuts of human experts. In this paper, we will argue that the difficulties in the integration of basic science and clinical knowledge in intelligent systems arise from ontological differences between these kinds of knowledge and that the solution can be found in their dynamic integration during the reasoning process. In order to illustrate this point, we will first describe an epistemological analysis of the interplay between basic science knowledge and clinical knowledge, and then we will provide the example of a computational architecture implementing this view. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
94.
目的: 分析影响维持性血液透析患者 (血透) 感染HCV 的因素。方法: 收集120 例血透患者的临床资料并进行统计学分析。结果: 血透患者HCV感染与血透时间、每周透析时间、输血、血制品史和量、肾移植史、院内感染史、ALT增高史显著相关。结论: 输血为血透患者感染HCV的主要途径, 但也存在医源性传播的可能  相似文献   
95.
目的:探讨维持性血液透析对老年人心血管系统的影响;方法:对46例老年维持性血透与50例非老年维持性血透对患者心血管系统的影响进行了分析比较;结果:维持性血透引起血压、高血压、心律失常、心绞痛、心力衰竭等心血管并发症,老年组显著高于对照组(P〈0.01)。因心血管并发症致死者,老年组占60.0%;结论:维持性血液透析对老年人尤易引起心血管系统并发症,并为其主要死亡原因。故在透析中有效防治心血管并发症  相似文献   
96.
Effect of metabolic acidosis on hyperlipidemia in uremia   总被引:2,自引:0,他引:2  
Nine patients (aged 18±1 years) on maintenance hemodialysis with metabolic acidosis and hyperlipidemia were studied before and after 2 weeks of oral sodium bicarbonate (NaHCO3) treatment to correct the acidosis. To control for the effect of additional sodium, they were also studied after 2 weeks of an equivalent amount of oral sodium chloride (NaCl). Oral NaHCO3 treatment led to significant increases in venous pH, serum bicarbonate, and serum 1,25-dihydroxyvitamin D3 concentrations, but no significant change in total and ionized calcium, phosphate, sodium, potassium, creatinine, blood urea nitrogen, and intact parathyroid hormone concentrations. Oral NaCl did not change any of the biochemical parameters. Before treatment of acidosis, these uremic patients had high serum triglycerides, low serum high-density lipoprotein (HDL) cholesterol, but normal total cholesterol compared with controls. Following 2 weeks of NaHCO3 treatment, there was a significant decrease in the serum concentrations of triglycerides (P<0.01). HDL and total cholesterol did not change. There were no changes in triglycerides, HDL or total cholesterol from baseline values following 2 weeks of NaCl. Thus treatment of metabolic acidosis ameliorated hypertriglyceridemia but had no effect on HDL and total cholesterol in patients with uremia on hemodialysis. The underlying mechanism may involve 1,25-dihydroxyvitamin D3. Received: 3 August 1998 / Revised: 30 November 1998 / Accepted: 2 December 1998  相似文献   
97.
 Amyloidosis is a complication of long-term hemodialysis treatment. The major histological feature of hemodialysis-associated amyloidosis (HAA) is the deposition of amyloid fibrils in the affected lesions, due, in part, to elevated serum β2-microglobulin (β2M) levels. In vitro studies reveal that serum immunoglobulin light and heavy chains co-deposit with β2M in tissues affected by HAA. Only one study of HAA has been performed in young dialysis patients. We therefore assessed risk factors for HAA in a group (n=30) of young (18.7±0.9 years) patients receiving chronic, uninterrupted hemodialysis using cellulose acetate membranes. All patients initiated dialysis before reaching 18 years of age. The pre-dialysis serum β2M level was 49.7±3.9 mg/l (normal 0–2.4 mg/l). Since serum albumin was normal (4.3±0.1 mg/dl) and serum protein/albumin was elevated (1.7±0.0, normal 1.2–1.5), indicating increased circulating protein, we assayed immunoglobulins in the same patients. The serum immunoglobulin levels (expressed as a percentage of the total level of serum proteins) were elevated (21.3±0.9%, normal 11.1%–21.0%). The Kt/v was 1.37±0.03, suggesting that the high levels of serum β2M and immunoglobulins were not due to inadequate dialysis in these patients. Patients with residual renal function (Kr) did display significantly lower serum levels of β2M (33.2±2.3, P=0.03). Furthermore, improved clearance of β2M correlated with higher values of Kr (r=0.914). In contrast, serum levels of immunoglobulin (22.6±3.7, P=0.5) were unaffected by Kr. In addition, there was no correlation between older age at onset of dialysis and serum levels of either β2M (r=0.107) or immunoglobulins (r=0.321). Finally, the length of time on dialysis had no effect on serum levels of either β2M (r=0.105) or immunoglobulins (r=0.092). Taken together, these results indicate that young hemodialysis patients may be at risk for HAA. Received: 13 January 1998 / Revised: 1 June 1998 / Accepted: 2 June 1998  相似文献   
98.
Autoimmune maintenance and neuroprotection of the central nervous system   总被引:6,自引:0,他引:6  
The genesis of immune privilege high in the evolutionary tree suggests that immune privilege is necessary, if not advantageous for the progressive development of the CNS. Upon reaching a certain degree of complexity, it seems as if the CNS was obliged to restrain the immune system from penetrating the blood-brain barrier. CNS autoimmunity against myelin proteins is known to be a contributory factor in the pathophysiology of multiple sclerosis and in the animal model of experimental autoimmune encephalomyelitis (EAE) (Wekerle, 1993). Such autoimmunity has therefore been regarded as detrimental and hence obviously undesirable. However, recent findings in our laboratory suggest that T-cell autoimmunity to CNS self-antigens (Moalem et al., 1999), if expressed at the right time and the right place, can do much good in the CNS. We shall review the experiments briefly, and then discuss their implications for our understanding of immune privilege and CNS maintenance after injury.  相似文献   
99.
Summary Since 1995 German health maintenance laws require hospitals to document and code all referals, admissions and discharges using the 4-digit ICD. Operative procedures are documented and coded using the ICPM. Beginning in January 1996, reimbursement for health services requires a diagnosis-related billing and payment for special procedures. The decision for billing is based on documented diagnosis and therapy. This extended request for documentation makes an online access to diagnosis and therapy with a computer-assisted coding system advisable. In 1996 in our hospital each diagnosis and operation was manually documented and coded on a form. Since the beginning of 1997, documentation and coding has been exclusively computer-assisted. On the basis of documented diagnosis and therapy the computer provides the route of reimbursement. Retrospectively we evaluated the number of charged diagnosis-related billings and payments for special procedures from January to April of 1996 and 1997. It became evident that with computer-assisted documentation and coding the number of detected and charged diagnosis-related billings and payments for special procedures was significantly increased in comparison with the previous year.   相似文献   
100.
定志丸对东莨菪碱诱发大鼠被动回避反应的影响   总被引:3,自引:0,他引:3  
唐·孙思邈《备急千金要方》的定志丸在防治记忆障碍作用上较《太平惠民和剂局方》记载的定志丸为佳。茯苓、远志、石菖蒲有协同人参之作用。《和剂局方》中的朱砂未见有改善学习记忆障碍的作用,故无组成方剂意义。  相似文献   
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