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1.
2.
In a genetic epidemiology study of a trait, prior to collecting genotype data the foremost task is to test for familial aggregation and examine heritability. Recently, functional traits have drawn attentions from investigators. Here, to test for familial aggregation of a functional trait in the family studies, a test constructed based on the leading functional principal component of heritability, which is a summary measure of temporal genetic variation in a functional trait, is proposed. The p‐value of the test can be approximated by a permutation procedure given the family structure. The asymptotic distribution of the test statistic is derived. Simulations are carried out to examine the size and the power of the test. The proposed methods are applied to the total cholesterol data in the Framingham Heart Study. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
3.
Cholesterol intakes in Britain have been re-estimated by analysing Total Diet samples taken in 1991 and from 1993 National Food Survey records. The Total Diet samples contained only 284 mg/day compared with 319 mg/day in 1987 and 337 mg/day in 1981, while the National Food Survey showed intakes had fallen to 238 mg/day from 259 mg/day in 1990 and 405 mg/day in 1970-75. More details of the intakes by adults in 1986/87 are given, and compared with the results from the other methods. Daily intakes of eight phytosterols were also estimated, the main ones being β-sitosterol, campesterol, stigmasterol and 57-stigmastenol whose intakes were 104, 49, 10 and 4 mg/day, respectively, in 1991. These intakes had increased since 1981, reflecting the rising consumption of vegetable oils.  相似文献   
4.
This report uses cross-sectional results from the Scottish Heart Health Study to investigate whether milk consumption has an independent effect on the prevalence of coronary heart disease. Milk consumption was assessed by questionnaire in men and women aged 40–59 years (n = 10359) who participated in a survey of risk factors for coronary heart disease between 1984 and 1986. Odds ratios for coronary heart disease were calculated according to volume and type of milk consumed for subjects with and without symptoms of coronary heart disease. Statistical adjustment was made for the classicial risk factors.
A higher percentage of men and women with diagnosed coronary heart disease (CHD) usually consume low-fat milk, compared with asymptomatic controls. Odds ratios for having undiagnosed heart disease did not differ significantly with volume or type of milk. However, the odds ratios for having diagnosed heart disease were lower in the moderate (0.5–1 pint/d) milk consumption group. Patterns of milk consumption in patients diagnosed as having CHD are likely to be confounded by dietary changes post-diagnosis. Milk consumption appears to have little independent effect on the prevalence of coronary heart disease in this Scottish population.  相似文献   
5.
不同病因腹泻病儿肠道主要菌群变化的研究和比较   总被引:1,自引:0,他引:1  
对88例不同病因腹泻儿肠道双歧杆菌、乳酸杆菌、大肠杆菌的变化进行研究。对照组25例。结果:研究组较对照组双歧杆菌、乳酸杆菌有显著下降(P<0.01和P<0.05),大肠杆菌下降不明显(P<0.05)。非感染性腹泻组较感染性腹泻组双歧杆菌、乳酸杆菌下降更显著(P<0.01和P<0.05),大肠杆菌下降不显著(P<0.05)。感染性腹泻组中,双歧杆菌在轮状病毒肠炎组中较急性菌痢下降更显著(P<0.05),而其它两种菌下降程度相差不明显(两者P<0.05)  相似文献   
6.
目的 对六草二苓汤治疗急性黄疸型病毒性肝炎的疗效进行对比临床研究,并探讨其作用机制。方法采用六草二苓汤的治疗组治疗急性黄疸型病毒性肝炎72例,并与使用肝泰乐、益肝灵、甘草甜素片的67例对照组作对比研究。结果 治疗组总有效率为93.1%,对照组总有效率为76.1%。在治疗后显效率、显效者复发率二方面,治疗组明显优于对照组(P<0.01)。在治疗前后主要症状体征变化、治疗前后肝功能变化、治疗后肝功能复常天数三方面,治疗组优于对照组(P<0.05)。结论 六草二苓汤治疗急性黄疸型病毒性肝炎,在较快地消除主要症状体征、消退黄疸、恢复肝功能、减少复发率方面有较好的疗效。  相似文献   
7.
院科两级病案质量评定误差因素的调查研究   总被引:5,自引:1,他引:4  
2002年某医院出院15448人次,全院科室评定病案质量平均甲级率为96.5%,而该医院病案质量检测办公室随机抽查了5010份病案,甲级率则为89.4%,二者之间存在着7.1%的差距。为了解存在误差的原因,我们对此进行了调查研究,分析了存在问题的原因,提出了对策性的改进措施。  相似文献   
8.
The present paper reports on the inaugural meeting of the Mental Health Special Interest Research Group (SIRG) of the International Association for the Scientific study of Intellectual disability which was held at Fitzwilliam College, Cambridge, UK, in March 1998. The meeting was organized in conjunction with the Ninth Annual SIRG on ageing and intellectual disability. Representatives from North America, several European and Scandinavian countries, Australia, and Israel attended. Two broad themes had been determined prior to the meeting: ‘Improving the detection of mental health problems’ and ‘Research strategies for identifying risk factors for mental health problems’. In the presentations and subsequent discussions, it was apparent that there were extrenely diverse perspectives both across and within the different countries represented. Not only were individuals' experiences very different, but most strikingly, the theoretical frameworks were very diverse. This was partly a function of there being understandable differences in perspectives across disciplines, but at its most marked, there were fundamental differences in the way both intellectual disability and mental health were conceptualized.  相似文献   
9.

Purpose

There is presently an ongoing debate on the relative merits of suggested criteria for spirometric airway obstruction. This study tests the null hypothesis that no superiority exists with the use of fixed ratio (FR) of forced expiratory volume in the first second (FEV1)/forced vital capacity (FVC) < 0.7 versus less than lower limit predicted (LLN) criteria with or without FEV1 <80% predicted in regards to future mortality.

Methods

In 1988–1994 the Third National Health and Nutrition Examination Survey (NHANES III) measured FEV1 and FVC with mortality follow-up data through December 31, 2011. For this survival analysis 7472 persons aged 40 and over with complete data formed the analytic sample.

Results

There were a total of 3554 deaths. Weighted Cox proportional hazards regression revealed an increased hazard ratio in persons with both fixed ratio and lower limit of normal with a low FEV1 (1.79, p < 0.0001), in those with fixed ratio only with a low FEV1 (1.77, p < 0.0001), in those with abnormal fixed ratio only with a normal FEV1 (1.28, p < 0.0001) compared with persons with no airflow obstruction (reference group). These remained significant after adjusting for demographic variables and other confounding variables.

Conclusions

The addition of FEV1 < 80% of predicted increased the prognostic power of the fixed ratio <0.7 and/or below the lower limit of predicted criteria for airway obstruction.  相似文献   
10.
采用定性分析与定量灰关联分析相结合的方法处理医学综合评价性的问题和诊断性的问题。定义了诊断值,诊断灰度和信息覆盖率等医学新概念,实例应用说明,这种分析研究和于临床诊断时,诊断符合率高,误诊率低,而且克服了一般医学诊断模式只能定性分析,不能作定量分析的缺点。  相似文献   
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