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41.
The value of inversion-recovery (IR) sequences in the diagnosis and staging of prostatic carcinoma with magnetic resonance (MR) imaging was studied. Twenty-six patients with carcinoma of the prostate were imaged at 1.5 T with an endorectal surface coil and with a variety of IR sequences and a set of spin-echo (SE) sequences for comparison. Ex vivo prostate specimens were imaged again at the same field strength. The two images were correlated with histologic sections. Cancer was identified with MR imaging in 96% of patients. Of the tumors more than 4 mm in diameter, 87% were identified on T2-weighted SE images, whereas only 26% were identified on IR images. However, IR images may be more useful in local staging of carcinoma. Gross capsular infiltration was present in only two patients; however, it was detectable (and excluded in five other patients) by means of IR images. It was not detectable on SE images. The high quality of images obtained with the endorectal coil was confirmed. The authors conclude that addition of the IR sequence to MR imaging with the endorectal coil may improve the usefulness of this examination.  相似文献   
42.
目的探讨心力衰竭并发心律失常的发病规律及治疗方法。方法回顾性分析了93例慢性心力衰竭病人的临床资料,包括临床特点、诊断治疗方法以及预后。结果心律失常发生率为60.2%,以室性早搏发生率最高32.1%,其次是房性早搏26.8%,心房纤颤21.4%,其他19.7%,经治疗有效71例,总有效率76.3%。结论纠正心功能不全是治疗的关键,应根据具体情况选择性地应用抗心律失常药。  相似文献   
43.
Objective To investigate the clinical characteristics and imaging manifestations of AIDS complicated with disseminated Penicillium marneffei (PM) infection. Methods A total of 12 patients with AIDS complicated with disseminated PM infection were collected and the symptoms, signs, laboratory examination results and image manifestations of these patients were analyzed retrospectively. Results (1) The diagnosis of PM infection in all the 12 cases were confirmed by peripheral blood culture. All the 12 cases (100%) had irregular fever (38-41℃) and enlarged lymph nodes, 8 cases (66%) had skin rashes; 8 cases (66%) had hepatomegaly; 9 cases (75%) had splenomegaly while 8 cases (66%) had anemia. (2) Imaging manifestation: Five cases manifested bilateral pulmonary disseminated miliary nodular shadows or lattice signs; 1 case showed enlarged hilar lymph node and 2 cases showed patchy shadow with pleuritis. One case presented sub-pleural curve line shadow at the posterior part of the right lower lung, and adhesion between the intestinal wall and intestinal mesentery in mass form in the abdomen by CT examination. Conclusion Patients suffering from AIDS (CD4 T lymphocytes 〈50/μ L) with impaired immunity might be susceptible to complication of disseminated PM infection, which presents mainly damage of multiple organs and symptoms such as fever; enlargement of liver, spleen and lymph nodes, as well as specific skin maculopapular rashes. Imaging manifestations in the lungs were revealed as miliary nodular shadows and lattice-like shadows. Intensified abdominal CT might reveal presence of several enlarged postperitoneal lymph nodes and intestinal adhesion in shape of "cakes".  相似文献   
44.
慢性多发性肌炎临床及病理分析   总被引:1,自引:0,他引:1  
目的探讨慢性多发性肌炎的发病机制、临床和病理特征。方法回顾性分析95例慢性多发性肌炎患者临床表现、肌酶学和肌电图检查结果,总结肌肉病理学特征。结果慢性多发性肌炎以四肢近端肌无力、肌萎缩为主要表现,血清酶谱轻-中度增高,肌电图以肌源性损害为主,病理改变为灶性坏死、炎性细胞浸润与再生肌纤维共存。结论临床特点结合病理学检查有助于慢性多发性肌炎的诊断,多数患者激素治疗有效。  相似文献   
45.
目的 :探讨单纯疱疹性角膜炎是中西医联合用药的治疗方法。方法 :本组 10 0例 ( 10 6只眼 )单纯疱疹性角膜炎患者应用抗病毒药物联合清热解毒中药的疗效观察。结果 :本组病例治疗后总有效率 82 .0 8%。结论 :中西医联合治疗措施是我们对单纯疱疹性角膜炎治疗的一项新的探讨。  相似文献   
46.
目的:探讨宫颈癌的临床、病理特点、诊治方法及预后因素。方法:收集1996年1月至2001年1月226例宫颈癌患者进行回顾性分析。结果:平均患病年龄为48.18岁。130例患者为阴道流血,70例为阴道流液,25例下腹疼痛,l例精神减退、贫血、浮肿。病理分期:Ⅰ期病例数为169例(75%);Ⅱ期病例数为3l例(13.72%);Ⅲ期病例数为23例(10.18%);Ⅳ期病例数为3例(1.1%)。比较2l例宫颈鳞癌与宫颈腺癌的转移,显示后者的腹主动脉旁淋巴结转移、肾上腺转移、子宫转移、胸水形成明显高于前者。结论:重视宫颈癌发病相关因素及临床症状,争取早期诊断,严格手术病理分期,选择适当治疗方案。  相似文献   
47.
多站点综合性毕业考试的改革与实践   总被引:5,自引:0,他引:5  
我校改革临床医学专业毕业考试模式与方法,在临床实习过程中组织多站点综合性考试,采用闭卷笔试方法考核临床理论知识,占70%;采用实践操作与现场口试方法考核临床技能及相关知识,占20%;采用开卷笔试方法考核医疗文书书写,占10%。实践证明,此项改革能促进医学生端正实习态度,调动实习的积极性与主动性,引导医学生在实习中重视理论学习与临床实践的密切结合,促进临床教学质量的提高。  相似文献   
48.
Physical inactivity, excess adiposity and premature mortality   总被引:5,自引:0,他引:5  
The purpose of this report is to review the evidence that physical inactivity and excess adiposity are related to an increased risk of all‐cause mortality, and to better identify the independent contributions of each to all‐cause mortality rates. A variance‐based method of meta‐analysis was used to summarize the relationships from available studies. The summary relative risk of all‐cause mortality for physical activity from the 55 analyses (31 studies) that included an index of adiposity as a covariate was 0.80 [95% confidence interval (CI) 0.78–0.82], whereas it was 0.82 [95% CI 0.80–0.84] for the 44 analyses (26 studies) that did not include an index of adiposity. Thus, physically active individuals have a lower risk of mortality by comparison to physically inactive peers, independent of level of adiposity. The summary relative risk of all‐cause mortality for an elevated body mass index (BMI) from the 25 analyses (13 studies) that included physical activity as a covariate was 1.23 [95% CI 1.18–1.29], and it was 1.24 [95% CI 1.21–1.28] for the 81 analyses (36 studies) that did not include physical activity as a covariate. Studies that used a measure of adiposity other than the BMI show similar relationships with mortality, and stratified analyses indicate that both physical inactivity and adiposity are important determinants of mortality risk.  相似文献   
49.
Theoretical and simulation evidence is presented in support of the idea that the optimal manner of determining blood flow from MR perfusion studies is not necessarily obtained by setting experimental conditions to maximize either the arterial input or the measured tissue concentration level for a particular echo time (TE). The noise power in the contrast concentration curve is associated with its peak because of the nonlinear relationship between the contrast concentration and MR signal intensity curves. The optimum signal-to-noise ratio (SNR), SNR(C), for a particular contrast concentration curve can be obtained when the experimental concentration level and TE are adjusted to produce an MR intensity curve whose signal loss is 63% of the precontrast MR signal intensity. It is demonstrated that the stability of the singular valued decomposition (SVD) deconvolution approach to determine blood flow parameters is increased when the tissue curve maximum signal loss is in the range of 40-80%. The accuracy and stability of the SVD-determined blood flow parameters are affected by deviations from these optimum conditions in a manner that depends on the mean transit time (MTT) associated with the residue function. It is recommended that the experimental TE value be set so that neither the tissue nor the arterial curves are placed a region of rapidly deteriorating SNR(C).  相似文献   
50.
Objective: The scientific quality of research is an important ethical issue. To clarify the quality of research projects in pharmacotherapy/pharmacology, 40 randomly selected research projects in pharmacotherapy/pharmacology submitted to a research ethics committee were reviewed. Results: Eight of the projects would not have contributed new knowledge nor were they necessary as controls for the results of previous research. Fifteen of the research protocols were of good quality, 15 could be used after revisions, and 10 were unfit for use. Eleven of the research projects were not finished 5 years after they were started. A written report was produced from 26 of the projects. Nine were of good quality and could be accepted for publication in a medical journal, 10 of the reports were in need of revision before publication, and 7 should not be accepted for publication. Conclusion: Research in this field ought to be improved, and ways to improve the standard of clinical trials in pharmacotherapy are dicussed. Received: 1 April 1996 / Accepted in revised form: 28 June 1996  相似文献   
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