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   1688篇
  免费   109篇
  国内免费   5篇
耳鼻咽喉   17篇
儿科学   71篇
妇产科学   30篇
基础医学   213篇
口腔科学   48篇
临床医学   172篇
内科学   413篇
皮肤病学   44篇
神经病学   164篇
特种医学   138篇
外国民族医学   1篇
外科学   180篇
综合类   19篇
预防医学   52篇
眼科学   23篇
药学   69篇
中国医学   1篇
肿瘤学   147篇
  2021年   13篇
  2019年   15篇
  2018年   21篇
  2017年   15篇
  2016年   25篇
  2015年   34篇
  2014年   41篇
  2013年   45篇
  2012年   45篇
  2011年   43篇
  2010年   61篇
  2009年   48篇
  2008年   48篇
  2007年   43篇
  2006年   50篇
  2005年   39篇
  2004年   42篇
  2003年   54篇
  2002年   56篇
  2001年   65篇
  2000年   53篇
  1999年   69篇
  1998年   51篇
  1997年   53篇
  1996年   50篇
  1995年   43篇
  1994年   29篇
  1993年   35篇
  1992年   32篇
  1991年   35篇
  1990年   29篇
  1989年   45篇
  1988年   43篇
  1987年   49篇
  1986年   40篇
  1985年   47篇
  1984年   25篇
  1983年   28篇
  1982年   25篇
  1981年   28篇
  1980年   14篇
  1979年   22篇
  1978年   12篇
  1977年   10篇
  1976年   14篇
  1974年   12篇
  1972年   10篇
  1969年   11篇
  1966年   8篇
  1965年   8篇
排序方式: 共有1802条查询结果,搜索用时 15 毫秒
71.
A multicentre double-blind comparison of choline magnesium trisalicylate (CMT) and acetylsalicylic acid (ACSA) compared the two medications for seven weeks in rheumatoid arthritis patients. Investigators measured the number of painful and swollen joints and the duration of morning stiffness, and assessed the overall condition of each patient. Both medications were highly effective in significantly reducing the severity of symptoms flaring after interruption of prior therapy. CMT achieved a greater reduction in the number of swollen joints than did ACSA (P less than 0.05). The incidence of adverse side-effects per patient was significantly less with CMT (P less than 0.05) (ACSA 32.1%; CMT, 16.3%. A larger percentage of ACSA patients (50.8%) reported adverse side-effects than did CMT patients 28.4%) (P less than 0.02).  相似文献   
72.
There is consensus that matching of unrelated donors (URD) and patients for HLA class II alleles improves the outcome of hematopoietic stem cell transplantation (HSCT). However, the significance of HLA class I allelic mismatches for transplant outcome is under discussion and reports on long-term effects like chronic graft-versus-host disease (GVHD) are rare. Thus, we investigated the association of human leukocyte antigen (HLA) class I allele mismatches and outcome in 144 patients given HSCT from URD who were matched for HLA-DRB1, DRB3/4/5, and DQB1 alleles. The risk of chronic GVHD was significantly increased in patients with class I mismatched donors, the mismatch either detected by low- or high-resolution typing. A single HLA class I allele mismatch significantly increased the risk of chronic GVHD in multivariate analysis. Overall survival was significantly reduced in patient/donor pairs with more than one-allele class I mismatch. Thus, selection of unrelated donors for transplantation should be based on high-resolution HLA class I typing.  相似文献   
73.
Summary Chromosome studies were performed in 24 patients who underwent allogeneic bone marrow transplantation (BMT) for severe aplastic anaemia (8), chronic myeloid leukemia (5 in chronic, 2 in accelerated phase and 1 in lymphoid blast crisis), acute myeloid leukemia (6), acute lymphoblastic leukemia in relapse (1) and Hodgkin's disease (1). Donor-cell type engraftment was demonstrated in 21 patients: in all 17 sex-mismatched transplants and — as demonstrated by reconstitution with Ph-negative cell populations — in 4 CML patients with a sex-matched donor. Recipient-type mitoses were seen in the bone marrow of 5 cases (1 SAA, 3 CML, 1 AML) after transplantation. They were only observed on one occasion in patients with SAA (4 of 25 on day 33) and AML (44 of 50 on day 14). Despite the continued demonstration of some Ph-positive mitoses in 3 patients with CML up to day 28, 323 and 451 after BMT, respectively, all surviving CML patients are still in complete haematological and clinical remission. So far the significance of these cytogenetically abnormal persisting host cells remains unknown. Present address: Roswell Park Memorial Institute, Department of Genetics and Endocrinology, 666 Elm Street, Buffalo, NY 14 222, USA  相似文献   
74.
75.
Breast cancer is the most common cause of cancer death in women in this country. Until recently, the traditional treatment has been radical surgery with or without radiation therapy for patients with primary breast cancer, and palliative endocrine therapy followed by chemotherapy for patients with advanced disease. These treatments have met with limited effectiveness in terms of eradicating the disease. Studies in the past decade have given cause for optimism for breast cancer patients. Adjuvant systemic therapy after local treatment appears promising for certain subsets of patients with primary breast cancer. The development of estrogen receptor assays has markedly changed our approach to the disease and improved patient care. Estrogen receptor is an important prognostic factor and is useful in planning appropriate therapy for patients with primary breast cancer as well as those with advanced disease. Further research is urgently needed to improve the dismal survival of certain women with this common malignancy.  相似文献   
76.

Purpose

In the two consecutive German studies III and IIIA on chronic myeloid leukemia, between 1995 and 2004, 781 patients were randomized to receive either allogeneic hematopoietic stem cell transplantation with a related donor or continued drug treatment. Despite comparable transplantation protocols and most centers participating in both studies, the post-transplant survival probabilities for patients transplanted in first chronic phase were significantly higher in study IIIA (144 patients) than in study III (113 patients). Prior to the decision on a combined analysis of both studies, reasons for this discrepancy had to be investigated.

Methods

The Cox proportional hazard cure model was used to identify prognostic factors for post-transplant survival.

Results

Donor–recipient matching for human leukocyte antigen, patient age, time between diagnosis and transplantation, and calendar time showed a significant influence on survival and/or the incidence of cure. Added as a further factor, affiliation to study IIIA had no significant impact any longer.

Conclusions

Discrepancies in influential prognostic factors explained the different post-transplant survival probabilities between the studies. The significance of calendar time suggests a lack of consistency of transplantation practice over time. Accordingly, the prerequisite for a common assessment of overall survival in the two randomized transplantation arms was not met. Moreover, our analyses provide an independent validation of established prognostic factors and their cutoffs. The statistical approach in investigating and modeling potential prognostic factors for survival sets an example for the examination of studies with unexpected outcome differences in concurrent treatment arms.  相似文献   
77.
Smoking cessation interventions for cardiac patients need improvement given their weak effects on long-term abstinence rates and low compliance by nurses to implementation. This study tested the effectiveness of two smoking cessation interventions against usual care in cardiac patients, and conditional effects for patients’ motivation to quit and socio-economic status (SES). An experimental study was conducted from 2009 to 2012 for which Dutch cardiac patient smokers were assigned to: usual care (UC; n = 245), telephone counseling (TC; n = 223) or face-to-face counseling (FC; n = 157). The three groups were comparable at baseline and had smoked on average 21 cigarettes a day before hospitalization. After six months, interviews occurred to assess self-reported smoking status. Patients in the TC and FC group had significantly higher smoking abstinence rates than patients in the UC group (p ≤ 0.05 at all times). Regression analysis further revealed significant conditional effects of the interventions on smoking abstinence in patients with lower SES, with a larger effect for TC than FC when compared to UC. These findings suggest that intensive counseling is effective in increasing short-term abstinence rates, particularly in patients with lower SES. Future studies need to investigate how patients with higher SES can profit equally from these type of interventions.  相似文献   
78.
Now is an exciting era of development in immunotherapy checkpoint inhibitors and their effect on the treatment of NPC. While the general prognosis of R/M disease is poor, immunotherapy offers some promise in a malignancy associated with EBV and characterized by a peritumoural immune infiltrate. Our study aims to review past and on-going clinical trials of monoclonal antibody therapies against the checkpoint inhibitors (e.g. PD1 and CTLA-4), in R/M NPC. All randomized and nonrandomized controlled trials involving immune checkpoint inhibitor interventions for treatment of NPC were included in the study. We utilized a validated “risk of bias” tool to assess study quality. Four separate Phase I–II trials report the potential of PD1 inhibitor treatment for patients with NPC. Within the observed groups, camrelizumab combined with chemotherapy achieved an objective response in 91% of patients as first-line treatment for metastatic NPC (PFS 68% at 1-year) but this was associated with a high rate of grade >3 adverse events (87%; CTCAE version 4.03). The remaining three studies focused on recurrent NPC disease in patients who had received at least one line of prior chemotherapy. Within this group, camrelizumab monotherapy achieved an objective response in 34% of patients (PFS 27% at 1-year; range across all three studies 20.5–34%). No NPC trial has yet reported on specific outcomes for non-PD1 checkpoint inhibitors but 11 on-going studies include alternative targets (e.g. PD-L1/CTLA-4) as combination or monotherapy treatments. In considering checkpoint immunotherapies for NPC, initial results show promise for anti-PD1 interventions. Further phase I–III trials are in progress to clarify clinical outcomes, fully determine safety profiles, and optimize drug combinations and administration schedules.  相似文献   
79.
80.
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