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   2057篇
  免费   71篇
  国内免费   6篇
耳鼻咽喉   3篇
儿科学   42篇
妇产科学   30篇
基础医学   350篇
口腔科学   9篇
临床医学   185篇
内科学   468篇
皮肤病学   22篇
神经病学   220篇
特种医学   26篇
外科学   226篇
综合类   7篇
预防医学   135篇
眼科学   11篇
药学   114篇
中国医学   4篇
肿瘤学   282篇
  2023年   9篇
  2022年   11篇
  2021年   25篇
  2020年   30篇
  2019年   33篇
  2018年   37篇
  2017年   21篇
  2016年   23篇
  2015年   30篇
  2014年   36篇
  2013年   65篇
  2012年   144篇
  2011年   160篇
  2010年   76篇
  2009年   65篇
  2008年   148篇
  2007年   182篇
  2006年   164篇
  2005年   154篇
  2004年   117篇
  2003年   139篇
  2002年   112篇
  2001年   30篇
  2000年   14篇
  1999年   21篇
  1998年   23篇
  1997年   31篇
  1996年   23篇
  1995年   10篇
  1994年   10篇
  1993年   16篇
  1992年   15篇
  1991年   13篇
  1990年   10篇
  1989年   11篇
  1988年   10篇
  1987年   10篇
  1986年   12篇
  1985年   8篇
  1984年   6篇
  1983年   5篇
  1979年   10篇
  1978年   6篇
  1976年   4篇
  1975年   4篇
  1974年   4篇
  1973年   6篇
  1971年   7篇
  1969年   4篇
  1968年   5篇
排序方式: 共有2134条查询结果,搜索用时 109 毫秒
71.
We here describe 13 patients with non-Hodgkin's lymphoma (NHL) and a translocation t(11:14)(q13:q32). They were part of a series of 163 patients with NHL and an abnormal karyotype, serially referred to our institution between January 1984 and 1990. Patients with t(11:14) seem to present several common and interesting features. Males are more frequently affected than females, and old people more than young. They present at diagnosis with advanced disease and usually show involvement of epithelium and bone marrow. With respect to histologic diagnoses, these patients are usually considered to be of low-grade malignancies. However, most of them do very poorly, have short complete remission and frequent relapses whatever the treatment. As a whole, the median survival rate is rather low. The cytologic, histologic as well as the immunologic patterns tend to be uniform: tumours are composed of small cells and display features of mantle zone/intermediate lymphocytic lymphoma. They express high IgM and low IgD levels and more commonly bear Ig lambda light chains. They also express all pan-B antigens (except CD23) as well as the CD5 antigen, but usually lack the CD10. According to these characteristics, these tumours could be placed in between lymphocytic lymphomas (which usually express CD23) and follicular lymphomas (which commonly lack IgD and CD5 and bear CD10 as well as a t(14:18).  相似文献   
72.
The rate of relapse after allogeneic bone marrow transplantation (BMT) varies between 15 and 60%. New therapeutic strategies are required urgently as no significant results have been obtained with standard chemotherapy. The best results of second allogeneic BMT have been obtained when the interval between the first and the second transplant was more than 6 to 20 months, depending on the study. Veno-occlusive disease was an important cause of non-leukemic death (13–65%). As the toxicity of second BMT is very high, other treatments have been considered: complete remissions were reported after sudden discontinuation of the immunosuppressive therapy. Interferon-alpha has been used for chronic myeloid leukemia patients and may achieve hematological and cytogenetic complete remission. More recently, donor leucocytes transfusions have been proposed and at least in some cases, have led to molecular complete remission (polymerase chain reaction with double amplification) in chronic myeloid leukemia patients. However, non predictable marrow aplasias and graft-versus-host reactions hamper the efficacy of this strategy. Finally, hemopoietic growth factors used to promote donor cell growth produce interesting results which deserve further studies.  相似文献   
73.
The prevalence of hepatitis C virus (HCV) infection was studied prospectively in pregnant women in France and their children by detection of anti-HCV with second-generation ELISA (ELISA2). In ELISA2-positive women, anti-HCV was detected with second- and third-generation RIBA (RIBA2 and RIBA3) and serum HCV RNA was detected with PCR. Among 670 women, anti-HIV1-negative, 26 (3.9%) were positive with ELISA2. RIBA2 was positive in 13 and HCV RNA was found in 10. Ten ELISA2-positive women had a further evaluation with assessment of HCV infection in their children. Among the 10 children born to the index pregnancy, only one was positive with ELISA2 and RIBA2 but negative with RIBA3 and PCR; the nine other children were ELISA2, RIBA2, RIBA3, and PCR negative. All 26 siblings (2–16 years old), of whom 14 were born to PCR-positive mothers, were ELISA2 and RIBA2 negative. We conclude that among anti-HIV1-negative pregnant women with normal serum ALT levels, the prevalence of HCV infection is relatively high but the risk for mother-to-infant transmission of HCV seems to be low.  相似文献   
74.
75.

Background

Liver stiffness evaluation (LSE) by Fibroscan is now widely used to assess liver fibrosis in chronic hepatitis C. Liver steatosis is a common lesion in chronic hepatitis C as in other chronic liver diseases, but its influence on LSE remains unclear. We aimed to precisely determine the influence of steatosis on LSE by using quantitative and precise morphometric measurements of liver histology.

Methods

650 patients with chronic hepatitis C, liver biopsy, and LSE were included. Liver specimens were evaluated by optical analysis (Metavir F and A, steatosis grading) and by computerized morphometry to determine the area (%, reflecting quantity) and fractal dimension (FD, reflecting architecture) of liver fibrosis and steatosis.

Results

The relationships between LSE and liver histology were better described using morphometry. LSE median was independently linked to fibrosis (area or FD), steatosis (area or FD), activity (serum AST), and IQR/LSE median. Steatosis area ≥4.0 % induced a 50 % increase in LSE result in patients with fibrosis area <9 %. In patients with IQR/LSE median ≤0.30, the rate of F0/1 patients misclassified as F ≥ 2 by Fibroscan was, respectively for steatosis area <4.0 and ≥4.0 %: 12.6 vs 32.4 % (p = 0.003). Steatosis level did not influence LSE median when fibrosis area was ≥9 %, and consequently did not increase the rate of F ≤ 3 patients misclassified as cirrhotic.

Conclusion

A precise evaluation of liver histology by computerized morphometry shows that liver stiffness measured by Fibroscan is linked to liver fibrosis, activity, and also steatosis. High level of steatosis induces misevaluation of liver fibrosis by Fibroscan.  相似文献   
76.
77.
78.
79.
The aim of the present study was to check whether platinum (Pt) concentrations achieved in tumors with a daily low-dose schedule were close to those promoting radiosensitization. Fifteen previously untreated patients with histologically proven advanced uterine cervix tumors were studied. They received a daily irradiation 30 min after a short infusion of 5 mg cisplatin for 5 consecutive days every week. A biopsy was taken from the accessible tumor mass, 4 to 6 hr after the daily injection. Blood samples were obtained once a week, just before the daily injection (H0) and 30 min after (H30). Quantificative analysis of Pt concentrations was performed by atomic absorption spectrophotometry. Plasma and tumoral Pt concentrations exhibited a marked intersubject variability. The median tumoral Pt concentration was 1,710 mg/g. Median total and ultrafiltrable Pt concentrations in plasma taken at H0 and H30 were 231 and 360 ng/ml, and 7 and 90 ng/ml respectively. Tumoral and total plasma Pt concentrations significantly increased during the course of treatment. Present data show that tumoral Pt concentrations achieved with this CDDP schedule are in the range of tumoral Pt concentrations previously shown to promote radiosensitization (2,000 ng/g). These results suggest that this CDDP radiosensitization regimen might be started with higher CDDP doses in order to reach earlier radiosensitizing Pt tumoral concentrations. © 1996 Wiley-Liss, Inc.  相似文献   
80.
(1) Background: There is much debate about the use of salt-restricted diet for managing heart failure (HF). Dietary guidelines are inconsistent and lack evidence. (2) Method: The OFICSel observatory collected data about adults hospitalised for HF. The data, collected using study-specific surveys, were used to describe HF management, including diets, from the cardiologists’ and patients’ perspectives. Cardiologists provided the patients’ clinical, biological, echocardiography, and treatment data, while the patients provided dietary, medical history, sociodemographic, morphometric, quality of life, and burden data (burden scale in restricted diets (BIRD) questionnaire). The differences between the diet recommended by the cardiologist, understood by the patient, and the estimated salt intake (by the patient) and diet burden were assessed. (3) Results: Between March and June 2017, 300 cardiologists enrolled 2822 patients. Most patients (90%) were recommended diets with <6 g of salt/day. Mean daily salt consumption was 4.7 g (standard deviation (SD): 2.4). Only 33% of patients complied with their recommended diet, 34% over-complied, and 19% under-complied (14% unknown). Dietary restrictions in HF patients were associated with increased burden (mean BIRD score of 8.1/48 [SD: 8.8]). (4) Conclusion: Healthcare professionals do not always follow dietary recommendations, and their patients do not always understand and comply with diets recommended. Restrictive diets in HF patients are associated with increased burden. An evidence-based approach to developing and recommending HF-specific diets is required.  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