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   313篇
  免费   23篇
  国内免费   1篇
儿科学   35篇
妇产科学   6篇
基础医学   40篇
口腔科学   1篇
临床医学   35篇
内科学   104篇
神经病学   13篇
特种医学   37篇
外科学   10篇
综合类   30篇
预防医学   7篇
眼科学   1篇
药学   8篇
肿瘤学   10篇
  2020年   2篇
  2019年   2篇
  2018年   6篇
  2016年   4篇
  2015年   7篇
  2014年   6篇
  2013年   7篇
  2012年   4篇
  2011年   2篇
  2010年   16篇
  2009年   11篇
  2008年   4篇
  2007年   13篇
  2006年   13篇
  2005年   7篇
  2004年   10篇
  2003年   10篇
  2002年   9篇
  2001年   8篇
  2000年   4篇
  1999年   8篇
  1998年   20篇
  1997年   21篇
  1996年   15篇
  1995年   14篇
  1994年   12篇
  1993年   8篇
  1992年   6篇
  1991年   4篇
  1990年   8篇
  1989年   8篇
  1988年   9篇
  1987年   6篇
  1986年   9篇
  1985年   3篇
  1984年   5篇
  1983年   2篇
  1982年   5篇
  1981年   3篇
  1980年   4篇
  1977年   3篇
  1976年   2篇
  1974年   1篇
  1973年   3篇
  1971年   1篇
  1970年   1篇
  1969年   2篇
  1968年   2篇
  1967年   3篇
  1966年   2篇
排序方式: 共有337条查询结果,搜索用时 15 毫秒
41.
42.
Porter  PN; Ogawa  M 《Blood》1982,59(6):1207-1212
Bone marrow conditioned media (BMCM) increases burst number and the incorporation of 59Fe into heme by bursts when peripheral blood or bone marrow cells are cultured at limiting serum concentrations. Burst- promoting activity (BPA) has now been purified approximately 300-fold from this source by ion-exchange chromatography on DEAE-Sephadex and absorption chromatography on hydroxyapatite agarose gel. Marrow BPA increased burst number and hemoglobin (Hb) synthesis in a dose- dependent manner. A larger increase in Hb synthesis than in burst number was consistently observed, which was probably a consequence of the increase in the number of cells per burst that occurs in the presence of BPA. The role of BPA in culture could be distinguished from erythropoietin (Ep), since no bursts grew in the absence of Ep, whether or not BPA was present, and since it had no effect on the growth of erythroid colonies scored at day 5 of culture. Our purified fraction did not support the growth of CFU-C in culture. Activity was stable at temperatures of 70 degrees C or lower for 10 min; exposure to 80 degrees C resulted in approximately 50% loss of activity. BPA was completely inactivated by treatment at 100 degrees C for 10 min. Thus, human bone marrow cells produce a heat-sensitive factor that specifically promotes the growth of early erythroid progenitors in culture.  相似文献   
43.
OBJECTIVE: To describe the outcome of patients with juvenile idiopathic arthritis (JIA) treated with subcutaneous (Sc) methotrexate (MTX) after failing oral MTX (either because of inefficacy or toxicity) in a clinic population. METHODS: The study cohort was identified from our clinical database, and consisted of 61 children with JIA treated with MTX between 1988-2001. All patients fulfilled International League Against Rheumatism (ILAR) criteria for JIA and had disease duration of >/= 6 months and 3 or more active joints before institution of MTX. All patients had a core set of outcome variables assessed at baseline and at 3 months after achieving both maximum oral and SC MTX. Outcome variables included physician global assessment of disease activity, number of active joints, number of joints with limited range of motion, duration of early morning stiffness, and erythrocyte sedimentation rate (ESR). Improvement was defined as at least 30% improvement from baseline in 3 of 5 variables in the core set, with no more than one of the remaining variables worsening by more than 30%. RESULTS: A total of 61 patients, 43 females and 18 males with JIA were studied. The disease subtypes were systemic 8, polyarticular 25 (12 rheumatoid factor positive), oligoarticular 14, enthesitis related arthritis 5, and unclassified 4. Thirty-one patients were switched to SC MTX, 13 of whom had not improved, and 18 who had improved, but had nausea (11) or insufficient clinical improvement (7). After 3 months of SC MTX treatment, 76% of patients were classified as improved and 23% as not improved. Toxicity on SC MTX was less than on oral MTX. CONCLUSION: Our results suggest that for patients failing oral MTX either because of inefficacy or toxicity, the use of SC MTX has a high likelihood of success with more than 70% of patients achieving clinically significant improvement, without clinically significant toxicity.  相似文献   
44.
The bleeding patterns of severe von Willebrand's disease (VWD) adversely affect quality of life, and may be life threatening. There is a presumed role for prophylaxis with VWF‐containing concentrates, but data are scarce. The von Willebrand Disease Prophylaxis Network (VWD PN) was formed to investigate the role of prophylaxis in clinically severe VWD that is not responsive to other treatment(s).Using a retrospective design, the effect of prophylaxis was studied. Availability of records to document, or reliably assess, the type and frequency of bleeding episodes prior to, and after, the initiation of prophylaxis was required. Annualized bleeding rates were calculated for the period prior to prophylaxis, during prophylaxis and by primary bleeding indication defined as the site accounting for more than half of all bleeding symptoms. The Wilcoxon signed‐rank test of differences in the medians was used. Sixty‐one subjects from 20 centres in 10 countries were enrolled. Data for 59 were used in the analysis. The median age at onset of prophylaxis was 22.4 years. Type 3 VWD accounted for the largest number (N = 34, 57.6%). Differences in bleeding rates within individuals during compared with before prophylaxis were significant for the total group (< 0.0001), and for those with primary bleeding indications of epistaxis (= 0.0005), joint bleeding (= 0.002) and GI bleeding (= 0.001). The effect of prophylaxis was similar among those age < 18 years and those ≥18. One person developed an inhibitor during treatment. We conclude that prophylactic treatment of VWD is efficacious.  相似文献   
45.
To evaluate the reliability of phosphorus-31 magnetic resonance (MR) spectroscopy in the assessment of acute testicular ischemia, vascular integrity, and spermatogenesis, the authors studied in vivo canine and primate testicles grouped as follows: group 1 testes (n = 8), in situ canine controls; group 2 (n = 11), canine testes subjected to warm ischemia; group 3, canine (n = 4) and primate (n = 4) testicles from hormone-treated animals. Group 1 control testicles showed high monophosphoester (MP) levels; low levels of inorganic phosphate (Pi), phosphodiester (PD), and phosphocreatine; and high levels of adenosine triphosphate (ATP). Group 2 testes revealed a time-dependent decay of MP/Pi ratios (from 2.1 to 0.70). Regeneration of ATP was noted in the acute reperfusion period. After 6 weeks of pituitary gonadotropin suppression, group 3 testes showed a significant decrease (P less than .05) in MP/PD ratios from a control level of 2.6 +/- 0.3 and a decrease in the MP/beta-ATP ratio from 2.4 +/- 0.1 to 1.8 +/- 0.3. P-31 MR spectroscopy appears to be a potential method for noninvasively assessing testicular ischemic injury and the metabolic integrity of spermatogenesis.  相似文献   
46.
SUMMARY The aim of this review is to sort out from the huge amount of facts related to digoxin in the literature those pertinent to current clinical practice. Seven aspects of digoxin are discussed: its mechanism of action, therapeutic controversy, clinical efficacy, avoidance of toxicity, manifestations of toxicity, indications, and its use in coronary artery disease  相似文献   
47.
Grunhaus L, Schreiber S, Dolberg OT, Hirshman S, Dannon PN. Response to ECT in major depression: are there differences between unipolar and bipolar depression? Bipolar Disord 2002: 4(Suppl. 1): 91–93. © Blackwell Munksgaard, 2002  相似文献   
48.
49.
50.
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