首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   672篇
  免费   67篇
  国内免费   4篇
耳鼻咽喉   13篇
儿科学   44篇
妇产科学   4篇
基础医学   54篇
口腔科学   60篇
临床医学   30篇
内科学   171篇
皮肤病学   27篇
神经病学   80篇
外科学   95篇
综合类   23篇
预防医学   36篇
眼科学   31篇
药学   16篇
中国医学   2篇
肿瘤学   57篇
  2024年   3篇
  2023年   12篇
  2022年   9篇
  2021年   11篇
  2020年   17篇
  2019年   22篇
  2018年   13篇
  2017年   19篇
  2016年   23篇
  2015年   19篇
  2014年   25篇
  2013年   56篇
  2012年   24篇
  2011年   25篇
  2010年   17篇
  2009年   32篇
  2008年   31篇
  2007年   37篇
  2006年   40篇
  2005年   25篇
  2004年   23篇
  2003年   24篇
  2002年   32篇
  2001年   23篇
  2000年   25篇
  1999年   23篇
  1998年   9篇
  1997年   20篇
  1996年   8篇
  1995年   11篇
  1994年   6篇
  1993年   7篇
  1992年   6篇
  1991年   6篇
  1990年   10篇
  1989年   8篇
  1988年   2篇
  1987年   4篇
  1986年   3篇
  1985年   4篇
  1984年   7篇
  1983年   1篇
  1982年   2篇
  1981年   4篇
  1980年   4篇
  1979年   5篇
  1978年   2篇
  1977年   2篇
  1976年   1篇
  1975年   1篇
排序方式: 共有743条查询结果,搜索用时 15 毫秒
91.
Valid classification of stroke is essential to initiate effective acute management and early secondary prevention strategies. To accurately evaluate stroke subtype a number of diagnostic procedures have to be performed. This study sought to investigate variations in use of diagnostic procedures across selected European hospitals. First-ever stroke patients were sampled over a 1-year period through 11 hospital-based registers across 10 European countries. We defined a diagnostic standard for valid aetiological classification of ischemic stroke including brain imaging, vascular imaging and echocardiography. The impact of socio-demographic, clinical and structural characteristics on performance of the diagnostic standard was assessed using multivariate logistic regression analyses. A total of 1721 patients were included in the study. 83.1% received brain imaging, ranging from 32.8% to 100%. The diagnostic standard was performed in 40.4% of stroke patients, ranging from 0% to 77.2%. Patients with increasing age ( P  < 0.001) and with more severe strokes ( P  = 0.001) were less probably to receive the diagnostic standard. Patients treated in stroke units and neurological departments were more frequently investigated with the diagnostic standard ( P  < 0.001). Less than half of hospitalized stroke patients across Europe underwent diagnostic procedures to allow for aetiological classification of stroke, which may hamper the initiation of effective early management and secondary prevention.  相似文献   
92.
We are in the midst of an increasingly acrimonious discussion regarding the use of mesh in pelvic reconstructive surgery. Modern mesh kits, aggressively marketed by biotech companies, have become widespread. At times, they are used inappropriately, and significant complications such as pain syndromes and erosion are not uncommon. While conventional alternatives such as sacrospinous colpopexy and Burch colposuspension are not without their problems either, the discussion surrounding mesh use has a character never encountered before in urogynaecology. Many colleagues feel that the resolution of this conflict may be found in large randomised controlled trials such as the PROSPECT trial currently being planned in the UK. I feel that such a trial may well do more harm than good, unless certain precautions are taken. In this opinion piece I'll try and explain why.  相似文献   
93.
Present prospective study was conducted on 350 patients presenting with chief complaints of impaired hearing and delayed speech from 1996–2006. The aim of the present study was to find out the prevalence of deafmutism in our area, the aetiology of childhood deafness and to ascertain the role of acoustic reflex test (ART) for hearing screening considering brain stem evoked response audiometry (BSERA) as gold standard. A detailed history, clinical and other relevant systemic examination and investigations were done to find out the cause. All patients were subjected to ART test and BSERA. Male to female ratio was 2.1:1. Prevalence was found to be 5.59 per one lac population in our district. The commonest age of presentation was in the second decade. The causes for childhood deafness were genetic (15.8%), embryopathies (10%), perinatal (10.8%) and postnatal problems (12.5%). In 50.6% cases it was aediopathic. Congenital syndromic abnormalities were found in 5.4% patients. In BSERA 21% patients were found to have residual hearing varying from 60 dB to 100dB. The positive predictive value of ART was found to be low (10.4%). Hence it was recommended that ART should not be used as screening tool for childhood deafness.  相似文献   
94.
Background: Are there sex differences in the etiology of high performance in science in childhood that could contribute to the under‐representation of women in scientific careers? In this study the relative contributions of genetic and environmental influences on high performance in science in both boys and girls were assessed using standard twin analyses. Methods: The sample included 3000 twin pairs from the UK Twins Early Development Study (TEDS). Science performance ratings based on the UK National Curriculum were collected from teachers when the twins were 9, 10 and 12 years old. Science excellence was defined as performing above the 85th percentile. Sex‐limitation liability threshold models were used to assess sex differences in etiology. Results: We found no evidence for quantitative or qualitative sex differences in the etiology of science excellence, which was moderately heritable (30–50%), and influenced by both shared (40–56%) and non‐shared (10–13%) environmental influences. Conclusions: Although boys and girls do not differ genetically in relation to school science performance per se, the under‐representation of women in scientific careers may be due to attitudes rather than aptitudes.  相似文献   
95.
Aims: The aim of this paper was to analyse the aetiology and characteristics of 2000 patients who visited a multidisciplinary bad breath clinic in Leuven, Belgium and to correlate organoleptic ratings with portable device measurements.
Materials and Methods: The characteristics and aetiology of breath malodour of two thousand consecutive patients who visited a halitosis consultation were explored by means of a standard questionnaire and a clinical examination, including organoleptic scores provided by a trained and calibrated judge, and a portable bad breath detector (Halimeter®).
Results: Most patients came without referral and had complaints for several years (mean: 7 years, SD: 8 years). For 76% of the patients, an oral cause was found [tongue coating (43%), gingivitis/periodontitis (11%) or a combination of the two (18%)]. Pseudo-halitosis/halitophobia was diagnosed in 16% of the cases; and ear, nose and throat/extra-oral causes were found in 4% of the patients. Most patients had an organoleptic score <3 and a Halimeter® value <240 p.p.b.
Conclusions: Even though it was observed that halitosis has a predominantly oral origin, a multidisciplinary approach remains necessary to identify ear, nose and throat or extra-oral pathologies and/or pseudo-halitosis/halitophobia.  相似文献   
96.
The need for research on dementia in developing countries   总被引:1,自引:0,他引:1  
Dementia is one of the commonest and most disabling late-life mental disorders. Its prevalence and incidence have been assessed in developed countries, and show little geographical variation between countries and regions. Although most older people live in developing countries, little research has been carried out in those settings. There is some evidence that age-specific prevalence rates for dementia in developing countries may be relatively low. More research is needed to allow developing countries to estimate the current extent, type and cost of medical and social service provision, and to make confident predictions of future need. Research in different cultures with different levels of economic and industrial development will also increase the variance of environmental exposure, facilitating the identification of environmental risk factors and gene–environment interactions for dementia. Research methodologies need to be adapted to the different circumstances of developing countries, with implications for sampling, cognitive screening and definitive dementia diagnosis.  相似文献   
97.
Abstract We tested the hypothesis that the febrile stress of routine vaccination would increase central apnoea in normal infants. Twenty-one normal infants had continuous overnight breathing and temperature recorded at home, before and after 58 routine vaccination episodes. Central apnoea, of at least 5 sec duration, was detected by computer algorithm and confirmed by human inspection. The longest recorded apnoea was 16 sec ( n = 1) during 3629 h of sleep. Overnight rectal temperature increased after vaccination (median 0.52°C, 95% CI 0.40, 0.65). Apnoea density reduced on 46/53 vaccination nights (median -29%, 95% CI -20, -37) followed by an increase on subsequent nights (median +10%, 95% CI +1%, +21%). Overall, apnoea density was similar during the 3 nights preceding and 4 nights following vaccination (median +1%, 95% CI +9,-6). The febrile stress of routine vaccination did not increase central apnoea in normal infants.  相似文献   
98.
Bladder pain syndrome (BPS) is a condition of chronic bladder pain or discomfort that can significantly disrupt normal daily activities and reduce quality of life. It can be difficult to diagnose and manage because of vague symptoms, a poorly understood aetiology and few universally effective treatments. This article reviews the current literature on BPS aetiology, clinical presentation, diagnosis, and treatment options.  相似文献   
99.
四川省于1979~1983年在秀山县试点取得一个县净化丝虫病的成功经验,并于1982年开始逐步在全省丝虫病流行区推广。30个流行县(市、区)在基本消灭丝虫病后三年内实施巩固措施,经过11—14年病原学、媒介和血清学监测已连续8~14年来检出微丝蚴血症者,9~14年未发现感染人体幼丝虫的蚊媒,纵向监测点人群抗体阳性率接近非流行区人群抗体水平,达到卫生部颁布的消灭丝虫病标准,证实基本消灭丝虫病后的巩固和监测措施适合四川省实际情况。分析认为基本消灭丝虫病后实施巩固措施和进行足够范围的人群横向监测和重点人群监测可较迅速彻底地检出和消除残存传染源,尽快达到消灭丝虫病的标准。  相似文献   
100.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号