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   2374894篇
  免费   195048篇
  国内免费   4215篇
耳鼻咽喉   34271篇
儿科学   72747篇
妇产科学   62930篇
基础医学   334894篇
口腔科学   67536篇
临床医学   215541篇
内科学   468677篇
皮肤病学   47930篇
神经病学   200788篇
特种医学   95967篇
外国民族医学   886篇
外科学   360428篇
综合类   56221篇
现状与发展   1篇
一般理论   977篇
预防医学   190606篇
眼科学   55465篇
药学   177538篇
  4篇
中国医学   4366篇
肿瘤学   126384篇
  2018年   24207篇
  2016年   20581篇
  2015年   23285篇
  2014年   33540篇
  2013年   50835篇
  2012年   68747篇
  2011年   72283篇
  2010年   42472篇
  2009年   40866篇
  2008年   68770篇
  2007年   73105篇
  2006年   74003篇
  2005年   72038篇
  2004年   69342篇
  2003年   67016篇
  2002年   66268篇
  2001年   112451篇
  2000年   116531篇
  1999年   98337篇
  1998年   27862篇
  1997年   25523篇
  1996年   25451篇
  1995年   24612篇
  1994年   23162篇
  1993年   21554篇
  1992年   79397篇
  1991年   76399篇
  1990年   73578篇
  1989年   70852篇
  1988年   65849篇
  1987年   64817篇
  1986年   61346篇
  1985年   58408篇
  1984年   44229篇
  1983年   37668篇
  1982年   22888篇
  1981年   20336篇
  1980年   19037篇
  1979年   41305篇
  1978年   28985篇
  1977年   24348篇
  1976年   22836篇
  1975年   23964篇
  1974年   29640篇
  1973年   28044篇
  1972年   26230篇
  1971年   24153篇
  1970年   22756篇
  1969年   21092篇
  1968年   19138篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
A patient with end-stage renal failure, two previously failed kidney transplants and high serum lymphocytotoxic antibody levels was transplanted electively with an ABO-mismatched, HLA-identical kidney from his sibling. Immunosuppression consisted of pretransplant splenectomy and plasma exchange, followed by rabbit antithymocyte serum, azathioprine, prednisone and plasma exchange in the early post-transplant period. He is now 3 years post-transplant with normal renal function on conventional immunosuppressive therapy. This case, and a review of the literature, suggest that ABO blood group incompatibility need not be an absolute barrier to successful kidney transplantation. ABO incompatible kidney transplantation may be a potentially fruitful area for further research as the demand for donor organs continues to outstrip the supply.  相似文献   
992.
Based on residue characteristic physical parameters, a new scoring matrix, called EMPAR, for amino acid exchanges in proteins was obtained. When comparing protein sequences for detecting homologies, the use of this matrix in place of the Dayhoff log-odds matrix yields results that reflect the topological similarities in the proteins. The use of EMPAR is equivalent to the parametric correlation coefficient approach of Ooi and his colleagues. This matrix correlates at 0.63 with the Dayhoff matrix.  相似文献   
993.
The records of 29 consecutive patients treated by a pure, open, anterior acromioplasty were reviewed retrospectively. Excluded from consideration were patients with the following pathologic diagnoses or histories: (1) previously attempted acromioplasty on the same shoulder; (2) intraoperatively confirmed rotator cuff tear; (3) any surgically treatable biceps tendon or acromioclavicular abnormality; (4) lost to follow-up study. Three different techniques were employed to perform the acromioplasties. The first technique required partial deltoid origin detachment with an osteotome. The second technique spared the deltoid origin, while again using an osteotome to perform the acromioplasty. The third technique also spared the deltoid origin but used a high-speed burr to perform the acromioplasty. Evaluated in terms of patient satisfaction, residual pain, length of convalescence, suboptimal results, and complications, the first technique proved to be the least effective. The second technique produced early, excellent results. The third technique, in which a burr was employed through an intact deltoid origin, was most effective; technically, the method was also relatively simple and reliable.  相似文献   
994.
Several reports in the literature suggest a relationship between lead intoxication and thermoregulatory capacity. To investigate the effects of lead on the control of body temperature, mice of the BALB/c strain were injected intraperitoneally with lead acetate (0 to 100 mg/kg) while colonic temperature was measured 30, 60, and 90 min post-injection at ambient temperatures (Ta) of 20 and 30 degrees C. Lead acetate caused a transient hypothermia, an effect which was augmented at cooler Ta's. In a second experiment, mice were injected with 100 mg/kg lead acetate and placed in a longitudinal temperature gradient to measure their preferred Ta. Lead acetate significantly reduced the preferred Ta during the first 30 min post-injection which augmented the lead-induced hypothermia. In a third experiment it was found that lead acetate-induced lethality was potentiated with increasing Ta. Hence, the hypothermic response to acute lead acetate treatment may be beneficial to survival.  相似文献   
995.
The Alaska mental health program is endowed with a 1-million-acre trust fund. A coalition of groups that make up the mental health constituency of the state united in a lawsuit to establish the trust. The history of this legacy, the struggle to realize its benefits, its current status, and some of its psychopolitical significance are discussed.  相似文献   
996.
997.
We isolated hybridoma cells, which secreted monoclonal antibody (MAb) 121 SLE, an IgM showing the following reactivities: (1) by immunodiffusion, MAb 121 SLE and MAb NS 19-9 (a monoclonal antibody directed against a sialylated Lewis(a) antigen called CA 19-9) showed an identical precipitin line with mucin preparation containing this CA 19-9; (2) by immunoradiometric assay, MAb 121 SLE totally inhibited fixation of radiolabelled MAb NS 19-9; (3) by immunoperoxidase, MAb 121 SLE stained the normal gastrointestinal mucosa of Le-positive individuals exclusively, and this staining disappeared after neuraminidase treatment, as observed using MAb NS 19-9. However, the pattern of the staining obtained with MAb 121 SLE differed slightly from that given by MAb 19-9 on the different positive areas of the gastrointestinal mucosae. These differences principally concerned the number of positive epithelial cells and the intensity of their staining; (4) moreover, antibodies against idiotype determinant of NS 19-9 antibody did not react with the antibody 121 SLE. We concluded that MAb 121 SLE is different from the MAb NS 19-9. However, both these antibodies were associated with the same molecular sialylated Lewis(a) structure.  相似文献   
998.
Outcomes were compared between consecutive patients who had received either total lymphoid irradiation (TLI) or immunosuppressant treatment for intractable rheumatoid arthritis (RA). There were 33 TLI and 32 immunosuppressive recipients; all patients had failed standard therapy. Average followup from the start of therapy was 2.7 years for TLI and 5.9 years for immunosuppressive recipients. Final disability levels were the same in both groups; mortality was equal in both groups as well. There were more hospitalizations for infections in the TLI group and the infecting organisms tended to be staphylococcus or gram negative organisms. Apart from infections, there were more adverse effects reported in the immunosuppressive therapy group.  相似文献   
999.
This paper provides a comprehensive methodological review of the literature assessing the relationship between marital satisfaction and communication. The investigations vary greatly in the adequacy of their assessment measures and soundness of their research design. Although it is generally concluded that both content and process communication are related to marital satisfaction, replication of the better designs is necessary. Specific findings and their practical implications for both future research and marital therapy are discussed.  相似文献   
1000.
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