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   13129篇
  免费   1509篇
  国内免费   66篇
耳鼻咽喉   128篇
儿科学   418篇
妇产科学   271篇
基础医学   2158篇
口腔科学   298篇
临床医学   1639篇
内科学   2542篇
皮肤病学   260篇
神经病学   1050篇
特种医学   518篇
外科学   1665篇
综合类   335篇
一般理论   16篇
预防医学   1483篇
眼科学   147篇
药学   1080篇
  1篇
中国医学   8篇
肿瘤学   687篇
  2021年   216篇
  2020年   105篇
  2019年   195篇
  2018年   221篇
  2017年   169篇
  2016年   208篇
  2015年   227篇
  2014年   298篇
  2013年   443篇
  2012年   576篇
  2011年   608篇
  2010年   326篇
  2009年   336篇
  2008年   538篇
  2007年   570篇
  2006年   579篇
  2005年   543篇
  2004年   532篇
  2003年   482篇
  2002年   444篇
  2001年   403篇
  2000年   428篇
  1999年   366篇
  1998年   202篇
  1997年   179篇
  1996年   174篇
  1995年   153篇
  1994年   137篇
  1993年   139篇
  1992年   272篇
  1991年   296篇
  1990年   277篇
  1989年   281篇
  1988年   270篇
  1987年   247篇
  1986年   221篇
  1985年   223篇
  1984年   204篇
  1983年   163篇
  1982年   111篇
  1981年   127篇
  1980年   116篇
  1979年   172篇
  1978年   166篇
  1977年   136篇
  1976年   117篇
  1975年   107篇
  1974年   143篇
  1973年   129篇
  1972年   100篇
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
101.
The implementation of a national cervical screening programme in Ireland will require agreement on achievable standards in reporting cervical cytology similar to those published by the NHS cervical screening programme. Due to the opportunistic nature of screening in the Republic of Ireland, national incidence figures for uterine cervical disease are not available. An audit of our practice was performed to find the incidence of human papilloma virus related cervical disease in our population. Our laboratory reported 158,066 cases from 1996-2000. The overall rate of dyskaryosis increased from 3.6% to 7.9%, mostly due to increased low grade dyskaryosis (up from 2.3% to 6.0%). High grade dyskaryosis also increased (from 1.3% to 1.9%), particularly in the under-25 year age group who account for a growing proportion of high grade dyskaryosis (from 15.4% of all high grade diagnoses in 1996 to 23.0% in 2000). The positive predictive value of a diagnosis of high grade dyskaryosis remained stable between 76.0 and 79.5%. While opportunistic screening data may not be directly applicable to the entire screening population it is hoped that these data may form a foundation on which to estimate national incidence figures and define achievable standards for cervical screening cytology in Ireland.  相似文献   
102.
The case of a white-heroin addict who developed disseminated candidiasis following coinfection byCandida glabrata andCandida albicans is reported. Genomic random amplified polymorphic DNA typing suggested that theCandida glabrata blood isolates originated in the oral cavity of the patient. This case strengthens the evidence thatCandida species other thanCandida albicans can be involved in the pathogenesis of disseminated candidiasis in heroin addicts.  相似文献   
103.
Proteins of Rous sarcoma virus   总被引:32,自引:0,他引:32  
  相似文献   
104.
Lymphokine production by human milk lymphocytes.   总被引:3,自引:1,他引:3       下载免费PDF全文
To assess the functional capability of human milk lymphocytes, we studied phytohemagglutinin-induced lymphokine production by breast milk and, for comparison, peripheral blood lymphocyte cultures. Two lymphokines, lymphocyte-derived chemotactic factor (LDCF) and immune interferon, were assayed in supernatants of milk and blood lymphocyte cultures obtained from women 2 to 6 days postpartum. Eleven parallel milk and blood samples were studied for LDCF production. In nine experiments, both milk and blood lymphocytes produced LDCF. In the two other experiments, milk cells did not produce LDCF. In 10 milk cultures studied, all produced interferon activity. Acid and heat lability characteristics were typical of immune interferon. These results further characterize milk lymphocytes as immunologically competent and possibly important effector cells in neonatal immunity.  相似文献   
105.
106.
107.
Polymorphisms in exon 1 of the MBL-2 gene, resulting in reduced plasma levels of mannose binding lectin, were significantly overrepresented in 23 patients with primary antibody deficiency and culture-proven mycoplasma infections (P = 0.0038). This association persisted with the inclusion of a further nine suspected (doxycycline-responsive) cases (P = 0.0087). The lectin was shown to bind to three strains of mycoplasma.  相似文献   
108.
BACKGROUND: Continence services in the UK have developed at different rates within differing care models, resulting in scattered and inconsistent services. Consequently, questions remain about the most cost-effective method of delivering these services. AIM: To evaluate the impact of a new service led by a continence nurse practitioner compared with existing primary/secondary care provision for people with urinary incontinence and storage symptoms. DESIGN OF STUDY: Randomised controlled trial with a 3- and 6-month follow-up in men and women (n = 3746) aged 40 years and over living in private households (intervention [n = 2958]; control [n = 788]). SETTING: Leicestershire and Rutland, UK. METHOD: The continence nurse practitioner intervention comprised a continence service provided by specially trained nurses delivering evidence-based interventions using predetermined care pathways. They delivered an 8-week primary intervention package that included advice on diet and fluids; bladder training; pelvic floor awareness and lifestyle advice. The standard care arm comprised access to existing primary care including GP and continence advisory services in the area. Outcome measures were recorded at 3 and 6 months post-randomisation. RESULTS: The percentage of individuals who improved (with at least one symptom alleviated) at 3 months was 59% in the intervention group compared with 48% in the standard care group (difference of 11%, 95% CI = 7 to 16; P<0.001) The percentage of people reporting no symptoms or 'cured' was 25% in the intervention group and 15% in the standard care group (difference of 10%, 95% CI = 6 to 13, P = 0.001). At 6 months the difference was maintained. There was a significant difference in impact scores between the two groups at 3 and 6 months. CONCLUSIONS: The continence nurse practitioner-led intervention reduced the symptoms of incontinence, frequency, urgency and nocturia at 3 and 6 months; impact was reduced; and satisfaction with the new service was high.  相似文献   
109.
Monoclonal antibodies (MCA) were obtained by immunizing BALB/c mice with 99% pure granulocytes from normal donors or with a whole leukocyte suspension obtained from a chronic myelogenous leukemia (CML) patient, and then fusing the mouse spleen cells with a 315–43 myeloma cell clone. Four MCA were selected and studied using ELISA, immunofluorescence, cytotoxicity assays, and FACS analysis. Antibodies 80H.1. 80H.3. and 80H.5 (from normals) and 81H.1 (from CML) detected antigens expressed on neutrophils. Antibodies 80H.1 and 80H.3 (lgG) also reacted with monocytes but not with other blood cell subsets. Antibodies 80H.5 and 81H.1 (lgM) were cytotoxic and reacted strongly with most of the cells of the neutrophil maturation sequence. i.e., myeloblasts, promyelocytes, myelocytes, and mature granulocytes. Antibodies 80H.5 and 81H.1 also inhibited BFU-GM and CFU-E. Antigens recognized by 80H.3. 80H.5, and 81H.1 were expressed both on a proportion of cells from HL.60, KG.1, ML.1, and K562 myeloid cell lines, and on a proportion of blast cells isolated from patients with acute myelogenous leukemia. They were not found on lymphoid cell lines or lymphoid leukemia cells. These MCA recognize either late differentiation antigens expressed on mature neutrophils and monocytes (80H.1 and 80H.3) or early differentiation antigens (80H.5 and 81H.1) specific to the granulocytic lineage. They may be useful for a better definition of those antigens specific to hematopoietic stem cells and their relationship with normal or neoplastic hematopoiesis.  相似文献   
110.
Studies that used the MMPI to predict the response of chronic low back pain patients to standard medical treatment have not produced definitive results. Patients seen in a university hospital orthopedic back pain clinic were given the MMPI before treatment, and 6 to 12 months later 76 patients completed follow-up forms that indicated their level of intensity during the previous week and their ratings of the success of treatment in relieving their pain as well as in enabling them to return to normal activities. Predictions of poor response were made in terms of either single MMPI scales or code types. Patients with poor outcome on two of the three criteria (level of pain intensity and ability to return to normal activities) had significantly higher scores on the Hs scale. The predicted high risk code types very accurately identified patients with poor response on the same two criteria; however, the code-type procedure overpredicted poor response in the good outcome group.  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