避孕措施与细菌性阴道病关系的研究

目的：探讨避孕措施与细菌性阴道病（BV）的关系，为预防BV、指导选择避孕措施提供依据。方法：对某医院妇科门诊接受计划生育服务的育龄妇女非选择性地进行BV筛检。以筛检出的267例BV患者为病例组，其余478例未患BV且无BV史的妇女为对照组进行病例对照研究。结果：与未采用避孕措施者比较，单因素logistic回归分析显示：BV与IUD有正关联，而与避孕套、口服避孕药（OC）无关联。经婚姻状况、性卫生、性行为习惯调整后，BV与IUD的关联仍有统计学意义（OR=2．364，95％C1：1．216～3．620），但与OC及避孕套使用无关。同IUD使用者比较，BV与避孕套使用呈负关联，调整后的OR=0．299（95％C1：0．158～0．566）；BV与OC使用间无关联。结论：使用IUD与未采用避孕措施者比较可能增加BV发生的危险，而避孕套使用者发生BV危险低于IUD使用者。无论从避孕还是预防BV角度，避孕套均是一种较好的选择。     

基于GMDH型神经网络的EEG分类研究

为了提高对不同认知状态下脑电信号(EEG)的分类正确率，提出一种GMDH型神经网络及改进的训练算法。此网络结构在演化中生成，分类规则由简单多项式表示，训练算法可防止出现过拟合。此网络用于区分算术运算和休息状态下的脑电信号，正确率达到84．5％，与标准前向型神经网络(FNN)比较，显示了较好的分类效果。     

益肾通淋汤防治草酸钙肾结石的实验研究

本文观察了益肾通淋汤对大鼠实验性草酸钙结石的防治实验。结果表明,实验组在草酸钙晶体数和聚体数、肾小管扩张数,肾钙含量等方面均少于对照组(P<0.05或P<0.01);同时观察了实验大鼠肾脏的一般组织学改变,可见对照组肾小管上皮细胞浊肿变性,甚至细胞崩解、细胞碎片,胞核和刷状堟PAS阳性物质脱落于管腔内,有的与结石晶体粘附,肾小管明显扩张,而实验组未见明显的组织学损害。因而认为益肾通淋汤可能是通过抑制草酸钙结晶的析出和聚集,改善肾组织细胞的代谢和功能,减少细胞器脱落成为结石核心和基质物质以及加速尿液排泄,促进微结石排出的途径而起到防治尿结石作用的。     

Hospital versus population controls in a retrospective study on diet and stomach cancer

The aim of the present study is to evaluate drawbacks and advantagesof the choice of hospital versus population controls in a casecontrol study on diet and cancer through the analysis of a retrospectivestudy on diet and gastric cancer (GC) conducted in Forli, Italy,involving 232 cases, 430 population controls and 252 hospitalizedcontrols. The present paper reports the comparison of resultson diet and GC risk obtained using the 2 types of controls.Population controls tended, in general, to eat all kinds offoods slightly more frequently (bread, pasta, cold cuts, freshfish, seasoned cheeses, legumes, garlic, onions and preservedfruits), with the exception of cooked vegetables, which werereported less frequently by population than by hospital controls.ORs for specific foods adjusted for confounders and other foodswere consistent in the separate models including populationand hospital controls respectively for all food groups, withthe exception of cooked vegetables which represented a protectivefactor only when hospital controls were considered (high consumers,population controls: adjusted, OR=0.9, trend p value 0.54; highconsumers, hospital controls, adjusted OR=0.5, trend p value<0.01). Hospital controls were slightly less often currentsmokers (22.6 versus 30.0%) and more often regular wine drinkers(57.5 versus 47.8%) compared with population controls, but noneof these variables was associated with GC risk. The main resultsin this study were consistent using both types of controls,nevertheless the distribution of some dietary variables notrelated to the disease under study differed between the 2 controlgroups, suggesting some caution in the use of hospital controlswhen studying diseases other than GC.     

中医药抗消化性溃疡复发的研究

总结了运用中医药疗法对68例消化性溃疡愈合后的患者追踪观察2～4年的临床疗效,显示其具有复发率低的优势;又根据消化性溃疡发生及复发的机制分析了所采用的预防性治疗措施的作用机理;还对溃疡病复发的一些相关问题作了简单论述。     

RESULTS OF EXTERNAL BEAM RADIOTHERAPY IN 448 PATIENTS WITH CLINICALLY LOCALIZED ADENOCARCINOMA OF THE PROSTATE

The results of external beam radiotherapy for clinically localized adenocarcinorna of the prostate in 448 patients treated in the period 1980–90 were reviewed. The average follow up was 4.9 years. The patients were aged 44–87 years (median 69 years) and all had histopathological evidence of adenocarcinoma by needle biopsy or transurethral resection of prostate. The histopathological grading was: 127 G₁; 154 G₂; 127 G₃; 12 G₄; 28 G_x. Clinical staging according to TNM (American Urological Association) was: 29 T₀ (A2); 4 T₁ (B1); 173 T₂ (B2); 176 T₃ (C1); 63 T₄ (C2); 3 T_x. Routine surgical pelvic lymph node staging was not performed but patients had radiological (computerized tomography scan or lymphogram) nodal staging: 350 N₀; 22 N₁; 12 N₂; 64 N_x. High energy linear accelerator external beam radiotherapy was given by multiple fields to total doses of 50–70 Gy (median 60 Gy). The majority of patients (307, 69%) was treated by a uniform policy under the care of one radiation oncologist (HM). The rates of local and distant failure at 5 years were 10% (s.e. = 2%) and 42% (s.e. = 3%), respectively. The late complication rate at 5 years was 25% (s.e. = 2%), comprising mild 16%, moderate 7% and severe 1.3%. The 5 year overall survival rate was 64% (s.e. = 2%) and the cancer-specific survival rate was 74% (s.e. = 3%). Both histological grade and clinical stage were strongly predictive of overall survival and distant failure. Only histological grade was predictive of local failure. Treatment with external beam radiotherapy for this common cancer resulted in survival and disease control rates that compare favourably with other published radiotherapy series and has been accompanied by acceptably low morbidity.     

Mammographic screening: case-control studies.

BACKGROUND: The case-control design can be used to evaluate the benefit of cancer screening programmes. MATERIALS AND METHODS: This paper outlines the main methodological features of the case-control design in this context, and indicates some potential biases. It also reviews the existing case-control literature on mammographic screening. RESULTS: Case-control studies consistently indicate a reduction of approximately 50% in breast cancer mortality associated with mammography. This result indicates greater benefit than shown in randomised trials; however, one should recognise that trials indicate effectiveness whereas case-control studies indicate efficacy. The two types of evidence are broadly compatible when one allows for screening non-compliance and contamination in the randomised trials. CONCLUSIONS: The case-control evidence supports and is consistent with the findings of randomised trials of mammography. Effectiveness estimates from trials indicate the benefit of screening to the population as a whole, and are pertinent to the public policy debate as to the value of offering screening. In contrast, case-control studies indicate benefit to actual screening participants. As such, case-control estimates of efficacy are appropriate for individual decision-making by women about their use of mammography when it is potentially available to them.     

A simple model describes large individual differences in simultaneous colour contrast

We report experimental evidence for substantial individual differences in the susceptibility to simultaneous colour contrast. Interestingly, we found that not only the general amount of colour induction varies across observers, but also the general shape of the curves describing asymmetric matching data. A simple model based on von Kries adaptation and crispening describes the data rather well when we regard its free parameters as observer specific. We argue that the von Kries component reflects the action of a temporal adaptation mechanism, while the crispening component describes the action of the instantaneous, purely spatial mechanism most appropriately labeled simultaneous colour contrast. An interesting consequence of this view is that traditional ideas about the general characteristics of simultaneous contrast must be considered as misleading. According to Kirschmann’s 4th law, for instance, the simultaneous contrast effect should increase with increasing saturation of the surround, but crispening predicts the converse. Based on this reasoning, we offer a plausible explanation for the mixed evidence on the validity of Kirschmann’s 4th law. We also argue that simultaneous contrast, the crispening effect, Meyer’s effect and the gamut expansion effect are just different names for the same basic phenomenon.