全文获取类型
收费全文 | 9804篇 |
免费 | 728篇 |
国内免费 | 62篇 |
专业分类
耳鼻咽喉 | 61篇 |
儿科学 | 188篇 |
妇产科学 | 50篇 |
基础医学 | 1307篇 |
口腔科学 | 38篇 |
临床医学 | 1018篇 |
内科学 | 1104篇 |
皮肤病学 | 16篇 |
神经病学 | 3364篇 |
特种医学 | 144篇 |
外科学 | 371篇 |
综合类 | 1154篇 |
预防医学 | 793篇 |
眼科学 | 11篇 |
药学 | 660篇 |
7篇 | |
中国医学 | 218篇 |
肿瘤学 | 90篇 |
出版年
2024年 | 26篇 |
2023年 | 227篇 |
2022年 | 387篇 |
2021年 | 658篇 |
2020年 | 563篇 |
2019年 | 478篇 |
2018年 | 441篇 |
2017年 | 551篇 |
2016年 | 482篇 |
2015年 | 365篇 |
2014年 | 925篇 |
2013年 | 936篇 |
2012年 | 598篇 |
2011年 | 700篇 |
2010年 | 470篇 |
2009年 | 468篇 |
2008年 | 432篇 |
2007年 | 385篇 |
2006年 | 309篇 |
2005年 | 219篇 |
2004年 | 151篇 |
2003年 | 145篇 |
2002年 | 99篇 |
2001年 | 83篇 |
2000年 | 54篇 |
1999年 | 44篇 |
1998年 | 48篇 |
1997年 | 29篇 |
1996年 | 39篇 |
1995年 | 29篇 |
1994年 | 32篇 |
1993年 | 28篇 |
1992年 | 18篇 |
1991年 | 15篇 |
1990年 | 28篇 |
1989年 | 7篇 |
1988年 | 16篇 |
1987年 | 10篇 |
1986年 | 11篇 |
1985年 | 16篇 |
1984年 | 5篇 |
1983年 | 4篇 |
1982年 | 7篇 |
1981年 | 10篇 |
1980年 | 7篇 |
1979年 | 7篇 |
1974年 | 4篇 |
1973年 | 5篇 |
1972年 | 3篇 |
1971年 | 5篇 |
排序方式: 共有10000条查询结果,搜索用时 724 毫秒
41.
Analysis is presented of the relationship between decline in ventilatory function and possible symptoms of bronchial hypereactivity. Data comes from three consecutive surveys within a 13-year follow-up study of a population sample of 1747 persons (718 males and 1029 females) who completed spirometric testing and interviews. Chest symptoms recorded in the two initial surveys were used as baselines for the prognostic study on FEV1 change. To evaluate changes in lung function the FEV1 decline index, expressed as percentage of FEV1 loss during the study period, was calculated. Chronic wheezing and asthma-like attacks were very strongly related to FEV1 baseline level. Multiple linear regression analysis for each separate symptom including age and smoking habits as confounders and showed that the FEV1 decline index was higher and more significant when wheezing and asthma-like attacks or chronic cough were present. When the combination of symptoms were introduced into the regression model, the effect of wheezing became insignificant. Only attacks of shortness of breath in both sexes and chronic cough in women were significantly associated with more rapid FEV1 decline. However, the effect of persistent wheezing in men had a rather substantial impact on FEV1 change. Comparing the effect of the number of cigarettes smoked with the effect of symptoms, one can see that FEV1 decline due to attacks of shortness of breath is comparable to that seen with heavy smoking. There was no strong evidence that the symptoms under study precede the more rapid FEV1 decline. 相似文献
42.
Martin Haupt Alexander Kurz Stefan Pollmann Barbara Romero 《Journal of neurology》1992,239(5):248-250
Summary Ninety outpatients with Alzheimer's disease according to ICD-10 diagnostic draft criteria were studied to test the hypothesis that cases with a familial aggregation are different from cases without such an aggregation with respect to cognitive impairment. In all cases the diagnosis of Alzheimer's disease was confirmed by prospective observation within 12 months of initial evaluation. Patients were divided into two groups: one consisting of 23 patients with a familial aggregation, the other consisting of 67 patients without secondary cases among first-degree relatives. By means oft-tests differences in impairment of cognitive functions between the groups were calculated. The results did not yield statistically significant differences between the groups for any of the neuropsychologically investigated cognitive deficits. Thus the hypothesis that the presence of a familial aggregation may lead to a distinct phenotype in Alzheimer's disease was not confirmed. 相似文献
43.
R. Raininko I. Elovaara E. Poutiainen A. Virta L. Valanne M. Haltia J. Lhdevirta 《European journal of neurology》1997,4(2):143-151
The course of the organic brain disease caused by human immunodeficency virus (HIV-1) was evaluated in a follow-up study. The primary material included 200 consecutive HIV-1 infected persons. Sixty-one subjects, in whom other brain-affecting factors were excluded, consented to the follow-up. They underwent 278 radiologic examinations: computed tomography, magnetic resonance imaging, or a combination of both (mean 4.6 examinations/subject). Clinical neurologic status and, in 40 subjects, cognitive performance were repeatedly evaluated. Sixteen subjects were followed up until death and 11 of them were autopsied. Median follow-up time was 27 mo (range 2.5–66 mo). The most common radiologic finding was atrophy, found in 19 subjects at study entry and developing in 10 subjects during the study. Twenty-four subjects (39%) showed the development and/or progression of atrophy. Atrophic changes progressed most rapidly in acquired immunodeficiency syndrome (AIDS), but mild developing/progressive atrophy was found even in 33% of asymptomatic or neurologically intact subjects. Cognitive and radiologic worsening were simultaneous in 6/7 subjects with declining neuropsychologic test performance. Signal intensity changes including HIV-1 leukoencephalopathy appeared in AIDS patients with clear cognitive decline. 相似文献
44.
M. Fujimura Y. Nishizawa M. Nishitsuji M. Abo T. Kita S. Nomura 《Clinical and experimental allergy》2003,33(5):588-594
OBJECTIVE: Cough variant asthma and atopic cough are different clinical manifestations of eosinophilic airway inflammation presenting with isolated chronic non-productive cough. The aim of this study was to examine the longitudinal change in pulmonary function in cough variant asthma and atopic cough. METHODS: Longitudinal change in FEV1 was prospectively examined in 20 patients with cough variant asthma, 14 patients with atopic cough and 271 asymptomatic healthy subjects. All were lifetime non-smokers. Of the 20 cough variant asthma patients, 13 were taking long-term inhaled corticosteroid therapy (ICS) (beclomethasone dipropionate 615 +/- 58 micro g/day) and the other seven were not. Spirometry was taken at first visit, after cough was almost completely relieved on therapy, and at least once every year for 5 or more years afterwards. RESULTS: The slope of longitudinal change in FEV1 was not significantly different among cough variant asthma patients (- 0.029 +/- 0.007/year), atopic cough patients (- 0.021 +/- 0.022/year) and asymptomatic subjects (- 0.028 +/- 0.002 L/year). In patients with cough variant asthma, the slope in patients not taking inhaled corticosteroids (ICS) was 0.032 +/- 0.007 L/year, which was not significantly different from that in patients taking ICS (- 0.027 +/- 0.010 L/year). CONCLUSION: Pulmonary function decline is not greater in cough variant asthma than atopic cough and the normal population, and long-term ICS has no effect on the decline in cough variant asthma. 相似文献
45.
Jonathan Parke Mark D. Griffiths Adrian Parke 《International journal of mental health and addiction》2007,5(1):39-52
Background Research has demonstrated that optimism and “positive illusions” can be used a coping mechanism among those facing adversity.
Gamblers are a little studied group who also experience adversity and uncertainty. They often feel considerable levels of
frustration, guilt, anger and a sense of feeling cheated after making significant losses. In order to deal with such feelings
it is hypothesized that these individuals will search for positive consequences from their behaviour in order to offset this
negative affect.
Objectives To (1) determine whether after gambling, gamblers compensate and reduce negative affect by identifying positive consequences
from experiencing a loss, and (2) identify types of strategies which gamblers employ and consider how these should be classified.
Materials and Methods Eighty-seven regular slot machine gamblers were interviewed in a variety of environments housing slot machines. Each participant
was asked a series of questions in a semi-structured format, to explore possible styles of positive thinking.
Results Nine types of ‘positive thinking’ experienced by gamblers were identified. These included Comparative thinking, Prophylactic thinking, Biased frequency thinking, Responsibility avoidance, Chasing Validation, Prioritization,
Resourcefulness, Thoughtfulness, and Fear Reduction. Gamblers who were positive thinkers experienced significantly less guilt than non-positive thinkers.
Conclusions While reduction of negative affect may be perceived as positive in many other contexts, it is argued that it may counteract
efforts to promote responsible gambling. Clinical implications and directions for future research are discussed. 相似文献
46.
47.
J C Henry T van Amelsvoort R G Morris M J Owen D G M Murphy K C Murphy 《Neuropsychologia》2002,40(5):471-478
Velo-cardio-facial syndrome (VCFS) is associated with deletions on the long arm of chromosome 22, mild intellectual disability, poor social interaction and a high prevalence of psychosis. However, to date there have been no studies investigating the neuropsychological functioning of adults with VCFS. We compared 19 adults with VCFS with 19 age, gender and IQ matched controls using a comprehensive neuropsychological battery. Compared to controls, adults with VCFS had significant impairments in visuoperceptual ability (Visual Object and Space Perception Battery), problem solving and planning (Tower of London) and abstract and social thinking (Comprehension WAIS-R). It is likely that haploinsufficiency (reduced gene dosage) of a neurodevelopmental gene or genes mapping to chromosome 22q11 underlies the cognitive deficits observed in individuals with VCFS. 相似文献
48.
吉林省经七年来的鼠情监测,基本查清与人们接触密切的鼠类,特别是传播疾病的主要鼠类的分布规律,分析出我省家鼠有两个高峰(6月和10~11月),野鼠也有两个高峰(6月和10月),这与我省流行性出血热两个高峰相吻合,鼠峰在病峰之前。1986年以后,由于我省开展大规模灭家鼠活动,家鼠高峰已不存在规律性。通过几年来的灭鼠活动,使家鼠密度呈下降趋势,城镇褐家鼠和小家鼠构成比发生变化。城镇未爆发家鼠型流行性出血热。鼠情监测为灭鼠防病工作提供了科学依据。 相似文献
49.
Functional decline in frail community-dwelling stroke patients 总被引:1,自引:0,他引:1
F. Landi G. Onder M. Cesari V. Zamboni A. Russo C. Barillaro R. Bernabei 《European journal of neurology》2006,13(1):17-23
Patients who suffer a stroke event are at high risk of functional decline after the post-acute rehabilitation period. The aim of the present study was the evaluation of factors associated with functional decline in a large sample of older patients with stroke living in the community. The study population consisted of all patients admitted to home care programs after a post-acute rehabilitation program--with at least 1 year of follow-up--in twenty-two Italian Home Health Agencies from 2000 to 2002 (n=1338). For the present study we selected 355 (26%) patients with diagnosis of stroke. After 1 year of in-home care program, 149 out of 355 stroke survivors (42%) had presented a worsening in the activities of daily living (ADL) scale score. In the final adjusted model, patients with cognitive impairment (OR 2.59, 95% CI, 1.45-4.64), pressure ulcer (OR 2.74, 95% CI, 1.45-5.18), urinary incontinence (OR 1.64, 95% CI, 1.01-3.29), or hearing impairment (OR 1.83, 95% CI, 1.02-3.29) were more likely to significantly decline in physical functioning after a period of 1 year in-home care program. Our study documents that functional decline of stroke patients was largely dependent on specific subjects' clinical characteristics. Three of four concomitant disabling conditions associated in our sample with functional decline--pressure ulcer, urinary incontinence, hearing--can be prevented and eventually treated or modified. Appropriate post-acute rehabilitation programs and adequate home care interventions focused on the prevention and treatment of these conditions might be correlated to better outcomes in older post-stroke patients. 相似文献
50.
The Effect of Antiepileptic Drugs on Cognition: Patient Perceived Cognitive Problems of Topiramate versus Levetiracetam in Clinical Practice 总被引:1,自引:0,他引:1
Hans-Peter R. Bootsma †Albert P. Aldenkamp Leonie Diepman Jacques Hulsman Danielle Lambrechts Loes Leenen Marian Majoie Ad Schellekens †Marc de Krom 《Epilepsia》2006,47(S2):24-27
Summary: Introduction: Neurocognitive complaints may interfere with long-term antiepileptic drug (AED) treatment and are an important issue in clinical practice. Most data about drug-induced cognitive problems are derived from highly controlled short-term clinical trials. We analyzed such cognitive complaints for the two most commonly used AEDs in a clinical setting using patient perceived problems as primary outcome measure.
Method: All patients of the epilepsy center Kempenhaeghe that received topiramate (TPM) or levetiracetam (LEV) from the introduction to mid 2004 were analyzed using a medical information system, an automated medical file. Patients were analyzed after 6, 12, and 18 months of treatment.
Results: Four hundred and two patients used either TPM (n = 260) or LEV (n = 142); 18 months retention showed a statistically significant difference, revealing 15% more patients that continued LEV compared to TPM: 18 months retention 46% for TPM and 61% for LEV [F (1.400) = 3.313, p = 0.043]. Neurocognitive complaints accounted for a significant number of drug discontinuations and especially the high frequency of neurocognitive complaints in the first period of TPM treatment appeared to be significant different from LEV [F(2,547) = 3.192, p = 0.042]. In the remaining patients, the difference in neurocognitive complaints was not statistically significant.
Conclusion: cognitive complaints are common in TPM treatment and frequently lead to drug withdrawal. The impact of LEV on cognitive function is only mild. This leads to a much higher (15%) drug discontinuation rate for TPM compared to LEV. 相似文献
Method: All patients of the epilepsy center Kempenhaeghe that received topiramate (TPM) or levetiracetam (LEV) from the introduction to mid 2004 were analyzed using a medical information system, an automated medical file. Patients were analyzed after 6, 12, and 18 months of treatment.
Results: Four hundred and two patients used either TPM (n = 260) or LEV (n = 142); 18 months retention showed a statistically significant difference, revealing 15% more patients that continued LEV compared to TPM: 18 months retention 46% for TPM and 61% for LEV [F (1.400) = 3.313, p = 0.043]. Neurocognitive complaints accounted for a significant number of drug discontinuations and especially the high frequency of neurocognitive complaints in the first period of TPM treatment appeared to be significant different from LEV [F(2,547) = 3.192, p = 0.042]. In the remaining patients, the difference in neurocognitive complaints was not statistically significant.
Conclusion: cognitive complaints are common in TPM treatment and frequently lead to drug withdrawal. The impact of LEV on cognitive function is only mild. This leads to a much higher (15%) drug discontinuation rate for TPM compared to LEV. 相似文献