东北地区2000～2005年住院军事飞行人员疾病构成和常见病疾病谱调查

目的 探讨东北地区2000～2005年住院军事飞行人员疾病的发生、发展与分布规律,为完善新时期飞行人员疾病预防、诊治和医学鉴定提供客观依据. 方法 采用流行病学回顾性调查方法 ,统计分析东北地区2000～2005年2223人次住院军事飞行人员的病例资料,并按国际疾病分类法第9版(ICD-9)编制"东北地区2000～2005年军事飞行人员疾病构成"和"东北地区2000～2005年军事飞行人员常见病疾病谱".应用SPSS 10.0统计软件进行统计分析. 结果 疾病构成显示,军事飞行人员肌肉骨骼系统疾病多年居首位,构成比是居第2位的消化系统疾病的2～3倍.与1995年比较,肌肉骨骼系统、感觉器官及泌尿生殖系统疾病的构成比上升显著;疾病谱显示腰椎间盘突出症、颈椎病、头痛、神经性耳聋和心律失常居前5位. 结论 21世纪前6年东北地区军事飞行人员常见病是腰椎间盘突出症、颈椎病、头痛、神经性耳聋和心律失常.提示转氨酶增高、半月板损伤和颈椎间盘突出症增加迅速,应引起关注.     

Endorectal surface coil MR imaging of prostatic carcinoma with the inversion-recovery sequence

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.     

广州市大学生尝试自杀现况及其影响因素分析

目的了解广州市大学生尝试自杀现状及其影响因素，为高校健康教育提供理论依据。方法采用整群随机抽样方法，用自编调查表对大学生进行问卷调查，在此基础上结合专题小组讨论的定性研究方法进行分析。结果大学生近1a内尝试自杀报告率为6．0％，不同性别、学校、专业的学生尝试自杀报告率差异无统计学意义（P〉0．05）；城镇学生尝试自杀报告率为6．6％，高于农村学生的4．2％（x^2=4．71，P=0．032）。对自杀行为的态度、朋友和家人有过自杀行为、消极应对、负性生活事件等是尝试自杀的危险因素，获得社会支持是尝试自杀的保护因素。定性访谈发现，学校几乎没有开展过自杀行为的健康教育活动，绝大部分学生对自杀行为持中立态度。结论加强健康教育、消除危险因素、提高保护因素可以最大限度地预防自杀.     

手助腹腔镜与开腹肝切除术的临床对照研究

目的：探讨手助腹腔镜肝切除术的可行性及微创性。方法：随机将60例肝切除患者分为两组,30例行手助腹腔镜肝切除术,30例行开腹肝切除术,比较两组的手术时间、术中出血量、切口长度、术后肛门排气时间、术后住院时间、术后并发症、术前及术后第1、4、7天C反应蛋白（CRP）及中性粒细胞的动态变化。结果：手助腹腔镜组与开腹组的平均手术时间（114.3minvs.105.8min）和切缘距肿瘤边缘（3.22cmvs.3.33cm）差异无统计学意义（P〉0.05）。手助腹腔镜组术中平均出血量明显少于开腹组（212mlvs.376.5ml,P〈0.05）,切口长度差异有统计学意义（6.95cmvs.22cm,P〈0.01）。手助腹腔镜组术后胃肠功能恢复时间明显早于开腹组（术后肛门排气时间2.34dvs.3.48d,P〈0.05）。手助腹腔镜组住院时间明显短于开腹组（8.35dvs.10.8d,P〈0.01）。手助腹腔镜组与开腹组均无严重并发症发生。两组术后第7天CRP值比较有显著差异（23.23vs.63.35,P〈0.05）。两组于术后第4天中性粒细胞值比较有显著差异（6.45vs.9.51,P〈0.05）。结论：手助腹腔镜肝切除安全可行,并且具有创伤小、术后康复快等特点,是值得选择的微创肝切除方式。     

Physical inactivity, excess adiposity and premature mortality

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.     

老年人前瞻性记忆损害的研究

目的 了解健康老年人前瞻性记忆改变的情况,初步探讨老年人基于事件的前瞻性记忆(EBPM)和基于时间的前瞻性记忆(TBPM)损害程度的区别.方法 建立前瞻性记忆的神经心理学测验方法,测试教育程度相匹配的40名健康老年人和40名健康成年人的EBPM和TBPM.结果 与成年组[EBPM(6.25±1.60)分;TBPM(5.38±0.87)分]相比,老年组的EBPM[(2.50±0.85)分和TBPM(4.93±1.07)分]均较成年组差(P＜0.01,P＜0.05),而EBPM损伤指数的差异亦有统计学意义(P＜0.01).老年组前瞻性记忆的EBPM和TBPM存在双分离.结论 老年人存在前瞻性记忆的损害,EBPM损害较TBPM损害更为显著.EBPM和TBPM的双分离表明其可能有不同的神经机制,推测额叶可能特异性地参与了EBPM.     

Signal-to-noise ratio effects in quantitative cerebral perfusion using dynamic susceptibility contrast agents.

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).     

Designed polyanionic coiled-coil proteins: acceleration of heparin cofactor II inhibition of thrombin

Novel polyanionic proteins were designed to increase the rate of heparin cofactor II (HC) inhibition of α-thrombin, an essential protease in the coagulation cascade. Two α-helical coiled-coil proteins, a 62-residue dimer containing 8 Glu residues (E8C) and a 104-residue dimer containing 14 Glu residues (E14C), plus two 31-residue control peptides containing 8 Glu residues each (E8A and E8B), were chemically synthesized, structurally characterized and enzymatically assayed. Circular dichroic spectrophotometry indicated that both E8C and E14C formed stable two-chain α-helical coiled coils at pH 7 and 25 °C. The control peptides were only partially α-helical. E14C remained folded at 90 °C but E8C was half unfolded at 49 °C. Coiled-coil proteins E8C and E14C maximally accelerated by 35- and 33-fold, respectively, the rate of HC inhibition of α-thrombin. None of these compounds accelerated antithrombin inhibition of α-thrombin, and neither control peptide accelerated HC inhibition of α-thrombin. Acceleration of the HC inhibition of α-thrombin showed bimodal dependence on the concentration of the polyanionic protein, which is consistent with formation of a HC-coiled-coil-thrombin ternary complex. The results suggest that antithrombotic polyanionic α-helical coiled-coil proteins can be designed and synthesized and that the occurrence of secondary structure can be correlated with biologcal activity. © Munksgaard 1995.