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   7779篇
  免费   689篇
  国内免费   30篇
耳鼻咽喉   51篇
儿科学   172篇
妇产科学   207篇
基础医学   1161篇
口腔科学   109篇
临床医学   1012篇
内科学   1592篇
皮肤病学   87篇
神经病学   607篇
特种医学   396篇
外科学   1014篇
综合类   210篇
一般理论   2篇
预防医学   880篇
眼科学   48篇
药学   553篇
  2篇
中国医学   3篇
肿瘤学   392篇
  2021年   101篇
  2020年   81篇
  2019年   103篇
  2018年   127篇
  2017年   119篇
  2016年   87篇
  2015年   118篇
  2014年   169篇
  2013年   252篇
  2012年   376篇
  2011年   413篇
  2010年   211篇
  2009年   181篇
  2008年   348篇
  2007年   312篇
  2006年   316篇
  2005年   298篇
  2004年   334篇
  2003年   316篇
  2002年   279篇
  2001年   301篇
  2000年   278篇
  1999年   256篇
  1998年   111篇
  1997年   102篇
  1996年   98篇
  1995年   95篇
  1994年   88篇
  1993年   74篇
  1992年   210篇
  1991年   196篇
  1990年   208篇
  1989年   172篇
  1988年   154篇
  1987年   140篇
  1986年   147篇
  1985年   136篇
  1984年   117篇
  1983年   91篇
  1982年   68篇
  1981年   55篇
  1979年   81篇
  1978年   61篇
  1977年   50篇
  1976年   46篇
  1975年   47篇
  1974年   68篇
  1973年   47篇
  1972年   46篇
  1970年   52篇
排序方式: 共有8498条查询结果,搜索用时 849 毫秒
1.
Aims. Functional connectivity is providing new insights into the network nature of epilepsy with growing clinical applications. Our objective was to validate a novel magnetoencephalography‐based method to non‐invasively measure the epileptic network. Methods. We retrospectively identified pediatric and adult patients with refractory focal epilepsy who underwent pre‐surgical magnetoencephalography with subsequent intracranial electrographic monitoring. Magnetoencephalography tracings were visually reviewed, and interictal epileptiform discharges (“spikes”) were individually marked. We then evaluated differences in whole‐brain connectivity during brief epochs preceding the spikes and during the spikes using the Network‐Based Statistic to test differences at the network level. Results. In six patients with statistically‐significant network differences, we observed substantial overlap between the spike‐associated networks and electrographically active areas identified during intracranial monitoring (the spike‐associated network was 78% and 83% sensitive for intracranial electroencephalography‐defined regions in the irritative and seizure onset zones, respectively). Conclusion. These findings support the neurobiological validity of the spike‐associated network method. Assessment of spike‐associated networks has the potential to improve surgical planning in epilepsy surgery patients by identifying components of the epileptic network prior to implantation.  相似文献   
2.
3.
Gonadoblastoma, a rare gonadal neoplasm, presents most frequently in phenotypic female or phenotypically male patients with dysgenetic gonads or undescended testes. To date, only 2 cases of gonadoblastoma have been reported in anatomically normal male patients with scrotal testes. Both of these patients presented with testicular masses and germ cell tumors. We report a case of a genotypically and phenotypically normal, fertile man with descended testes who on evaluation for chronic orchialgia had a gonadoblastoma unaccompanied by a germ cell neoplasm. The tumor was nonpalpable and was initially discovered on scrotal ultrasound.  相似文献   
4.
The acting or interim leadership position has been neglected in terms of selection, role identification, and status. Individuals, programs, and organizations are paying a price for this inattention.  相似文献   
5.
The traditional role of the high school based community community health nurse has changed considerably over recent decades. This article describes a qualitative study, in which nine community health nurses from eight different high schools completed a diary of the interventions and events during the course of two working days in order to identify the dimensions of their role. A short demographic questionnaire was also completed by the nurses and included two open-ended questions concerning their main professional issues and concerns. The researchers sought verification of the interpretation of the data through a focus group interview with the high school nurses. Data analysis indicated that the role of the high school community health nurses (CHN) consisted of seven categories. These were provider of clinical care, counsellor/ mediator, advocacy and support, liaison/referral, health promotion/education and resource agent, and professional management and research role. The findings highlight the complex and demanding aspects of the role of the high school nurse and articulate the importance of describing the contribution of such practitioners in to the promotion of health among adolescents.  相似文献   
6.
Intraperitoneal (i.p.) injection of platelet activating factor (PAF) in guinea pigs caused a dose-related increase in the number of eosinophils recovered from bronchoalveolar lavage fluid (BALF). The prevalence of eosinophils in BALF had significantly increased within 1 hr of i.p. injection of PAF (10 micrograms/animal) and was maximal after 24 hr. Subcutaneous osmotic mini-pumps were used to administer drugs for 5 days prior to i.p. injection of PAF (10 micrograms/animal) and for the subsequent 24 hr. The percentage increase of eosinophils in BALF, due to PAF, was inhibited in animals treated with dexamethasone, aminophylline, cromoglycate, tranilast or ketotifen, but not in animals treated with oxatomide, azelastine, amlexanox, ibudilast or AA-861. These results suggest that inhibition of pulmonary eosinophilia may be a necessary property of prophylactic anti-asthma drugs and provide indirect evidence favoring a role for PAF in eosinophilia of asthma.  相似文献   
7.
Colonoscopy and bacteraemia: an experience in 50 patients   总被引:1,自引:0,他引:1  
There is little consensus concerning the incidence of bacteraemia during colonoscopy and the need for antibiotic prophylaxis in susceptible patients. Hepatic abscesses in one patient which may have been related to prior colonoscopic examinations led the authors to carry out a prospective study of 50 patients undergoing colonoscopy. Multiple blood cultures were carried out to maximise the positive yield of transient bacteraemia and to attempt to determine the time when bacteraemia is most likely to occur. Five patients had positive blood cultures. In two patients S epidermidis was isolated, but only from the precolonoscopic blood sample. In three subjects enteric organisms were cultured from blood samples obtained during the procedure. In one of these three the same organism was cultured from the preendoscopic blood sample so that in only two patients (4%) could the bacteraemia be attributed to the colonoscopy. These results would suggest that the risk of bacteraemia during colonoscopy is low.  相似文献   
8.
9.
A manic depressive illness is diagnosed in many women of childbearing age; thus they are candidates for lithium therapy. Since lithium has the most clearly documented teratogenic effect of all the psychotropic drugs, special care must be taken by the physician and patient when considering its use during this period of life. A review of the literature is presented and suggested guidelines are given for the use of lithium in this at-risk population.  相似文献   
10.
We describe a 15-y-old girl with Fechtner-like syndrome, who is the first Chinese reported to have this rare syndrome. She presented with left homonymous hemianopia and neuroimaging revealed haemorrhage in both parietal and occipital lobes. Peripheral blood smear showed macrothrombocytopenia and intracytoplasmic inclusion bodies inside leucocytes. Thrombocytopenia and proteinuria responded to intravenous immunoglobulin and pulsed methylprednisolone. This case illustrates that life-threatening haemorrhage can occur in patients with Fechtner syndrome. Although there was no effective treatment reported in the literature, high dose steroid and immunoglobulin seemed to be useful in our patient. Our patient also had nephritic-nephrotic syndrome with renal insufficiency, which is unusual in adolescent female patients.  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