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   25261篇
  免费   1975篇
  国内免费   47篇
耳鼻咽喉   282篇
儿科学   911篇
妇产科学   580篇
基础医学   3383篇
口腔科学   752篇
临床医学   2993篇
内科学   4361篇
皮肤病学   364篇
神经病学   2259篇
特种医学   981篇
外国民族医学   1篇
外科学   3970篇
综合类   558篇
一般理论   13篇
预防医学   2424篇
眼科学   615篇
药学   1372篇
中国医学   30篇
肿瘤学   1434篇
  2022年   174篇
  2021年   369篇
  2020年   230篇
  2019年   372篇
  2018年   506篇
  2017年   355篇
  2016年   333篇
  2015年   407篇
  2014年   680篇
  2013年   962篇
  2012年   1324篇
  2011年   1380篇
  2010年   826篇
  2009年   703篇
  2008年   1176篇
  2007年   1299篇
  2006年   1227篇
  2005年   1282篇
  2004年   1177篇
  2003年   1091篇
  2002年   1004篇
  2001年   569篇
  2000年   568篇
  1999年   530篇
  1998年   352篇
  1997年   262篇
  1996年   259篇
  1995年   218篇
  1994年   235篇
  1993年   214篇
  1992年   477篇
  1991年   405篇
  1990年   377篇
  1989年   379篇
  1988年   378篇
  1987年   334篇
  1986年   345篇
  1985年   348篇
  1984年   261篇
  1983年   272篇
  1982年   203篇
  1981年   217篇
  1980年   193篇
  1979年   279篇
  1978年   219篇
  1977年   178篇
  1976年   169篇
  1975年   167篇
  1974年   199篇
  1973年   211篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
Summary: We report a series of 8 patients with ictal déjà vu. Subdural strip electrocorticographic (ECoG) monitoring localized the ictal epileptogenic focus as follows: right (n = 6) and left (n = 2) mesiotemporal lobe. In all 8 patients, the left hemisphere was dominant for language function based on intracarotid amytal testing. In 6 right-handed patients, ictal déjà vu was associated with a right temporal lobe focus. However, in the 2 left-handed patients, the ictal focus was left temporal lobe. Although ictal déjà vu localizes the epileptic focus to temporal lobe, this experiential phenomenon appears to lateralize to the hemisphere nondominant for handedness.  相似文献   
32.
Combined high grade sarcoma and serous ovarian neoplasm.   总被引:1,自引:0,他引:1       下载免费PDF全文
A case of an ovarian serous epithelial neoplasm of borderline type admixed with sarcomatous elements is reported. This combination seems to be extremely rare with only four cases previously reported. It may represent a type of collision tumour or the development of a sarcoma in a growth with borderline differentiation.  相似文献   
33.
34.
Co-existence of facial and occipital pain may occur in occipital neuralgia, migraine and cluster headache; suggesting convergence of trigeminal and cervical afferents. Such convergence has been shown in humans and other animals, but the site and extent of this are uncertain. In anaesthetized adult cats, the superior sagittal sinus and occipital nerve were stimulated electrically, and extracellular recordings made in the dorsolateral area of the upper cervical cord using glass-coated tungsten electrodes. Of 49 units in 10 cats, 33 (67%) had input from the superior sagittal sinus and the occipital nerve. Thirteen (27%) had superior sagittal sinus input and 3 (6%) had occipital nerve input. Convergent receptive fields were identified mechanically in 7 units. These experiments in cats show convergent input from occipital nerve and superior sagittal sinus on dorsolateral area units in two-thirds of cases studied. This experimental site of trigeminocervical convergence may relate to referral of pain in occipital neuralgia and other headaches.  相似文献   
35.
I Ahmad  T M Allen 《Cancer research》1992,52(17):4817-4820
Liposome entrapment of doxorubicin has been shown to reduce its cardiotoxicity in vivo and increase its therapeutic index. A further improvement in therapeutic index could be achieved through targeting of liposome-entrapped drug selectively to cancer cells. Monoclonal antibodies against the squamous lung cancer cell line KLN-205 have been ligated to the surface of long-circulating (Stealth) and conventional liposomes. The antibody-bearing liposomes showed specific, competitive uptake by KLN-205 cells as compared to liposomes bearing nonspecific isotype-matched antibodies or antibody-free liposomes. Doxorubicin-containing antibody-liposomes resulted in as much as a 15-fold decrease in the 50% inhibitory concentration for doxorubicin against KLN-205 cells as compared to free doxorubicin or doxorubicin entrapped in antibody-free liposomes.  相似文献   
36.
Genetic analysis of a set of six Mycobacterium tuberculosis strains differing in virulence for the guinea pig revealed an altered restriction enzyme fragmentation pattern associated with the superoxide dismutase (SOD) gene in a low-virulence, isoniazid-resistant strain. In addition, it was found that the SOD enzyme produced by the isoniazid-resistant strain differed in its electrophoretic mobility from the SOD of other M. tuberculosis strains. Detailed analysis of these strain-specific differences showed that the restriction fragment length polymorphism resulted from the presence of a copy of a repetitive element 552 bp upstream of the SOD gene and that the anomalous electrophoretic mobility arose from a single nucleotide change, resulting in replacement of an aspartic acid residue by histidine in the SOD enzyme of the isoniazid-resistant strain. Possible relationships between genetic changes and strain-dependent differences in virulence are discussed.  相似文献   
37.
A fatal case of strychnine intoxication is reported. The patient expired despite early aggressive management and prevention of metabolic complications. Serial blood levels are reported. In contrast to a previous report describing first order elimination kinetics, our data suggest that strychnine follows Michaelis-Menton elimination kinetics. The case illustrates the rapid, dramatic course of severe strychnine ingestions. A review of the toxicokinetics, mechanism of action and treatment of strychnine intoxication follows.  相似文献   
38.
In patients with PG-dependent renal function, NSAID administration constantly reduces GFR and RBF in a dose-dependent fashion. In this situation, the risk of overt acute renal failure is high and should be taken into proper account. In contrast, the incidence of NSAID-related renal structural alterations appears to be very low, yet the absolute number of patients may be significant considering the wide use of such drugs. Concerning the antiproteinuric effect of NSAIDs, the unfavourable ratio risk/benefit does not seem to support their indication in proteinuric nephropathies. The development of PGHS-2 selective inhibitors is promising, and may open new therapeutical strategies in the treatment of the progression of renal disease.   相似文献   
39.
40.
Medical complications of prematurity   总被引:4,自引:0,他引:4  
The improved survival of extremely premature infants has generated intense interest in the quality of life of the survivors. This review focuses on the major long-term complications of prematurity (developmental disability, retinopathy of prematurity, chronic lung disease) and concludes with an overview of the broader spectrum of morbidity. Severe impairment (cerebral palsy, mental retardation, retrolental fibroplasia, severe chronic lung disease) fortunately occurs in a small proportion of survivors. However, the prevalence of the lesser morbidities (minimal cerebral dysfunction/learning disability, poor growth, postneonatal illnesses, rehospitalization) is less clearly defined. These problems all have an impact on families, and on medical and educational services.  相似文献   
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