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   1583篇
  免费   85篇
  国内免费   9篇
耳鼻咽喉   4篇
儿科学   63篇
妇产科学   165篇
基础医学   210篇
口腔科学   42篇
临床医学   141篇
内科学   281篇
皮肤病学   54篇
神经病学   93篇
特种医学   154篇
外科学   153篇
综合类   78篇
预防医学   40篇
眼科学   4篇
药学   100篇
  1篇
肿瘤学   94篇
  2022年   10篇
  2021年   27篇
  2020年   8篇
  2019年   8篇
  2018年   41篇
  2017年   26篇
  2016年   41篇
  2015年   43篇
  2014年   48篇
  2013年   73篇
  2012年   71篇
  2011年   66篇
  2010年   63篇
  2009年   54篇
  2008年   55篇
  2007年   51篇
  2006年   57篇
  2005年   32篇
  2004年   40篇
  2003年   45篇
  2002年   39篇
  2001年   32篇
  2000年   29篇
  1999年   33篇
  1998年   36篇
  1997年   55篇
  1996年   57篇
  1995年   44篇
  1994年   39篇
  1993年   41篇
  1992年   42篇
  1991年   28篇
  1990年   29篇
  1989年   30篇
  1988年   33篇
  1987年   19篇
  1986年   14篇
  1985年   23篇
  1984年   19篇
  1983年   15篇
  1982年   21篇
  1981年   18篇
  1980年   16篇
  1979年   12篇
  1978年   9篇
  1977年   10篇
  1976年   20篇
  1975年   13篇
  1973年   7篇
  1923年   9篇
排序方式: 共有1677条查询结果,搜索用时 0 毫秒
61.
Immunological and functional protein S, protein C and antithrombin III levels and anticoagulant responses to activated protein C were measured in 24 patients with stroke in childhood. No hereditary deficiencies were found. The protein S levels in healthy controls of younger age did not differ from the adult levels. For optimal screening of protein S deficiency, measurements using functional as well as immunological assays are recommended. Appropriate criteria for the diagnosis of the deficiencies must be carefully applied if unnecessary anxiety and inappropriate treatment of children are to be avoided.  相似文献   
62.
The diagnosis of brain death in the newborn infants is elusive and often difficult. The lack of cerebral blood flow has become an identified criterion for loss of cerebral function. The diagnosis can be obtained by the technique of digital subtraction angiography, which is presented in two case reports demonstrating the utility of this technique.  相似文献   
63.
64.
BACKGROUND: Interleukin-2 (IL-2) and granulocyte-macrophage-colony stimulating factor (GM-CSF) are cytokines with nonoverlapping pleiotropic effects. In a prior Phase Ib study, this combination of agents exhibited antitumor effects in the lungs of four of eight patients with renal cell carcinoma and pulmonary metastases. We conducted this Phase Ib/II trial to determine the response rate of renal cell carcinoma patients with pulmonary metastases treated with continuous infusion IL-2 plus GM-CSF. METHODS: Patients with renal cell carcinoma and pulmonary metastases were treated with 1.5, 2.25, or 4.5 x 10(6) IU/m(2)/day 96-hour continuous infusion IL-2 on Days 1-4, 8-11, and 15-18, and 1.25, 2.25, or 2.5 microg/kg/day GM-CSF on Days 8-19. RESULTS: Sixteen patients were treated per protocol, 14 of whom could be evaluated for disease progression. None of these 14 patients had >50% shrinkage of either total tumor burden or pulmonary metastasis. One patient developed Grade 5 neurotoxicity. Autopsy revealed acute multifocal cerebral venous thrombosis as well as acute subdural and subarachnoid hemorrhage. CONCLUSIONS: The combination of IL-2 and GM-CSF may be associated with marked morbidity and, as in one case in this study, mortality. No significant antitumor activity was appreciated. Thus, the combination of IL-2 and GM-CSF, when administered at this dose and according to this schedule, does not appear to be active in renal cell carcinoma and is associated with significant toxicities. Further studies using this combination of agents should only be undertaken with extreme caution and particular attention to neurotoxicity.  相似文献   
65.
66.
There is disagreement among authors as to what criteria are most reliable in assessing postnatal fetal age. A comparison–for objectivity, accuracy, and frequency of use– of specific criteria was made using three independent examiners at different educational levels: a second-year medical student, a perinatal nurse practitioner, and a pediatrics resident. It was shown that trained examiners develop favorite criteria which differ among examiners and thus sacrifice accuracy; however, accurate assessment of fetal age can be accomplished by an examiner with minimum clinical knowledge.  相似文献   
67.
Arterial hypoxemia induced by fiberoptic bronchoscopy   总被引:3,自引:0,他引:3  
R E Albertini  J H Harrell  N Kurihara  K M Moser 《JAMA》1974,230(12):1666-1667
  相似文献   
68.
69.
Drug-resistant lymphocytes in man as indicators of somatic cell mutation   总被引:1,自引:0,他引:1  
Direct in vivo tests of somatic mutation in man may provide realism in assessing the genetic risks of potential environmental mutagens. The autoradiographic determination of purine analogue (8-azaguanine; 6-thioguanine) resistant (AGr; TGr) peripheral blood lymphocytes (PBLs) arising in vivo in man is proposed as a candidate test. PBLs bearing the naturally occurring Lesch-Nyhan (LN) mutation are prototype mutant cells. LN PBLs are AGr and TGr, whereas normal PBLs are AG and TG sensitive. When judged by the inhibition of phytohemagglutinin (PHA) stimulated 3H-thymidine incorporation in vitro, analogue-resistant LN PBLs may be distinguished from analogue-sensitive normal PBLs by several methods. Early studies quantitating PHA stimulation by scintillation spectrometry detected down to 1% of LN PBLs in artificial mixtures with normal PBLs. Although LN heterozygous females could be identified on the basis of lymphocyte mosaicism, scintillation spectrometry was too insensitive to detect rare "LN-like" PBLs in non-LN individuals. Autoradiography, however, detected rare TGr PBLs in normal non-LN individuals. Their frequencies did not increase with age. With this method, TGr PBL frequencies in LN heterozygous females were found to range from 1 x 10(-3) to 5 x 10(-2), whereas blood samples from LN males showed from 23% to 100% TGr cells. Rare LN PBLs could be detected in artificial mixtures with normal cells. Studies in human patients undergoing various potential mutagenic therapies assessed the effects of these therapies on the TGr PBL variant frequencies (Vf) of non-LN individuals. Group TGr PBL Vf values were higher in treated patient groups than in controls. However, some untreated patient groups (cancer and psoriasis) also had elevated values, suggesting that disease itself may affect TGr PBL frequencies. Nonetheless, one patient group (vitiligo) showed elevated Vf values in treated (8-methoxypsoralen and long-range UV light = PUVA) but not in untreated patients, suggesting that treatment was responsible for the TGr PBL elevations. Longitudinal studies over time in cancer patients receiving X-irradiation therapy demonstrated that such exposures also are associated with TGr PBL frequency rises and suggested that longitudinal studies may be necessary to relate TGr PBL Vf elevations to specific environmental influences. Variant TGr PBLs were found at frequencies comparable to those in man in the peripheral blood of rats. They increased in a single study following treatment of the animals with a clinical alkylating agent. Characterization of the TGr PBLs suggests that some of these cells are mutants. Presumably the mutant cells arise in vivo by somatic cell mutation.  相似文献   
70.
The author believes that professional advice given the parents of a mongoloid infant determines their initial decision on institutionalization. Multidisciplinary counseling by the health team can help parents decide on a course of action that will prove satisfactory in the long run. Consultation should include health t e r n efforts to help parents work through the mourning process and presentation of a) an objective, comprehensive view of the child's condition, b) information on integrating a mongoloid into the family unit, and c) outside resources available to the parents. Deliberation with the parents to help them reach their own decision is essential.  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