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21.
22.
目的:痛经的发病率逐年增高,重新分析痛经患者的临床因素,提出新的认识。方法:将1 158例痛经患者的临床资料及超声检查结果进行统计学分析。结果:人工流产史与痛经的发生有密切相关性(P<0.001)。结论:人工流产手术是引起痛经的主要原因。该手术所产生的副作用可对女性生理健康造成严重伤害,必须引起全社会的高度关注。  相似文献   
23.
Most ureteral tumors are transitional cell neoplasms. Neuroendocrine tumors of the genitourinary tract are extremely rare. To our knowledge, only one ureteral carcinoid tumor has been reported before. We report a second case of ureteral carcinoid tumor found in a 70-year-old female.  相似文献   
24.
Clinical decisions are often made with incomplete information, yet patient care decisions are made every day. Patients vary clinically, uncertainty exists in diagnostic and prognostic information, and many preventive and treatment alternatives have not been formally assessed for their effectiveness. Because scientific information will never answer all clinical questions, clinical decisions are partially based on probabilistic information.
This paper describes how to apply clinical decision making to diagnosing and managing dental caries and periodontal diseases. By using explicit information to quantify probabilities and outcomes, clinical decision making analyzes decisions made under uncertain conditions and the uncertain impact of clinical information.
Clinical decision making incorporates concepts for preventing, diagnosing and treating dental caries and periodontal diseases: risk assessment, evidence-based dentistry, and multiple oral health outcomes. This information can serve as a tool for clinicians to augment clinical judgment and expertise.  相似文献   
25.
PTEN及Bcl-2蛋白在膀胱移行细胞癌中的表达及其意义   总被引:1,自引:0,他引:1  
乔宝民  孙光  畅继武  韩瑞发  王文成  马腾骧 《天津医药》2006,34(12):844-845,I0004
目的:探讨PTEN及Bcl-2蛋白在膀胱移行细胞癌的表达规律及其临床意义。方法:应用免疫组织化学链亲和素-生物素-霉复合物(SP)方法检测43例膀胱移行细胞癌和7例正常黏膜组织中PTEN及Bcl-2蛋白的表达.分析二者的表达与膀胱癌病理参数的关系。结果:(1)G1、G2、G3肿瘤PTEN表达阳性率分别为85.7%、80.4%、73.3%,浸润性肿瘤和表浅性肿瘤表达阳性率分别为70.4%和93.8%,说明PTEN表达阳性率与肿瘤病理分级、临床分期有关。(2)G。、G2、G3肿瘤Bcl-2表达阳性率分别为14.2%、57.14%、66.67%,浸润性肿瘤和表浅性肿瘤表达阳性率分别为59.3%和43.8%,说明Bcl-2表达阳性率与肿瘤病理分级、临床分期有关。(3)随着肿瘤恶性程度的增高和临床分期进展,PTEN蛋白阳性率呈下降,Bcl-2表达呈增高趋势,二者表达呈负相关关系。结论:PTEN的抑癌作用可能与Bcl-2有关.二者的异常表达在膀胱移行细胞癌的发生、发展过程中起重要作用。二者同时检测有助于判断预后。  相似文献   
26.
脑血管病诊治研究新策略探索及其评介   总被引:16,自引:10,他引:6  
脑卒中作为发病率、致残率最高的疾病,一直备受广泛的瞩目,随着脑卒中诊治研究不断地深入发展进步,近年来的新认识与探索呈现出爆炸式增长。我们在此扼要评介脑血管病诊治研究中热点问题及其相关新策略,以期引起同道们更深入地关注。  相似文献   
27.
INTRODUCTION: Vasopressin, mainly through the V1a-receptor, is thought to be a major player in the maintenance of hyperfiltration. Its inhibition could therefore lead to a decrease in progression of chronic renal failure. To this end, the effect of the vasopressin V1a-receptor-selective antagonist, YM218, was studied on proteinuria and focal glomerulosclerosis in early and late intervention after 5/6 nephrectomy in rats, and compared with an angiotensin-converting enzyme inhibitor (ACE-I). MATERIALS AND METHODS: After 5/6 nephrectomy, early intervention was performed between week 2 and 10 thereafter with the V1a-receptor-selective antagonist (VRA, 10 mg/kg/day, n=10), enalapril (ACE-I, 10 mg/kg/day, n=9), or vehicle (n=8). Late intervention was performed in another group between week 6 and 12 with VRA (10 mg/kg/day, n=7), lisinopril (ACE-I, 5 mg/kg/day, n=7), or vehicle (n=7). RESULTS: In early intervention, proteinuria and focal glomerulosclerosis were significantly decreased by VRA compared to vehicle (44+7% and 59+8% respectively). ACE-I significantly decreased proteinuria (67+7%) and a trend towards a decrease in focal glomerulosclerosis was observed (30+18%). In late intervention, VRA did not decrease proteinuria and focal glomerulosclerosis compared to vehicle (21+20% and 0%, respectively), ACE-I significantly lowered proteinuria (92+2%) and a focal glomerulosclerosis (69+1%) lowering trend was observed. CONCLUSION: These results indicate that VRA may protect against early progression of renal injury after 5/6 nephrectomy, whereas its effectiveness seems limited in established renal damage.  相似文献   
28.
Animal models have traditionally provided the basis for preliminary investigation of new techniques prior to trials taking place in human subjects. The timing of when to proceed with human trials is difficult, as the accuracy of preclinical models can only be determined with hindsight. This review outlines the progression from transplantation in animal models to man. Now that many transplant procedures are well established, it is possible to assess the predictive value and limitations of animal models. These results are of great importance in the current debate about composite tissue allotransplantation (CTA) and in particular facial transplantation. This progression of CTA from animal models to man is outlined and compared with early renal, cardiac, and liver transplants. There is some evidence to suggest that animal models may have been misleading in CTA and that this has effectively delayed the transition to humans. The role for animal models in facial transplantation, which is currently making the step to clinical trials, is discussed.  相似文献   
29.
鸡抗内毒素卵黄抗体IgY的制备   总被引:2,自引:1,他引:1  
目的:研究分别应用内毒素(LPS)、类脂A(LipidA)和大肠杆菌突变株15免疫鸡后其蛋黄中抗内毒素抗体IgY的产量、纯度、效价并筛选最佳免疫抗原。方法:分别应用内毒素(LPS)、类脂A(LipidA)和大肠杆菌J5突变株作为抗原免疫25周龄Leghom鸡,水溶法(WD)提取蛋黄中抗体IgY,双紫外光测定抗体含量,SDS-PSGE电泳检测抗体纯度,细胞酶联染色和ELISA检测抗体特异性、效价及筛选最佳免疫抗原。结果:3种抗内毒素IgY含量和效价分别为14.4mg/ml和1:12 800(J5)、10.61mg/ml和1:12 800(LPS)、9.26mg/ml和1:3200(LipidA),抗体纯度均为95%左右。结论:大肠杆菌突变株J5和内毒素(LPS)为最佳免疫抗原,免疫鸡后其蛋黄中抗内毒素抗体IgY的产量和效价最高。  相似文献   
30.
Some 50% of human cancers are associated with mutations in the core domain of the tumor suppressor p53. Many mutations are thought just to destabilize the protein. To assess this and the possibility of rescue, we have set up a system to analyze the stability of the core domain and its mutants. The use of differential scanning calorimetry or spectroscopy to measure its melting temperature leads to irreversible denaturation and aggregation and so is useful as only a qualitative guide to stability. There are excellent two-state denaturation curves on the addition of urea that may be analyzed quantitatively. One Zn2+ ion remains tightly bound in the holo-form of p53 throughout the denaturation curve. The stability of wild type is 6.0 kcal (1 kcal = 4.18 kJ)/mol at 25°C and 9.8 kcal/mol at 10°C. The oncogenic mutants R175H, C242S, R248Q, R249S, and R273H are destabilized by 3.0, 2.9, 1.9, 1.9, and 0.4 kcal/mol, respectively. Under certain denaturing conditions, the wild-type domain forms an aggregate that is relatively highly fluorescent at 340 nm on excitation at 280 nm. The destabilized mutants give this fluorescence under milder denaturation conditions.  相似文献   
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