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   35505篇
  免费   2084篇
  国内免费   162篇
耳鼻咽喉   383篇
儿科学   673篇
妇产科学   490篇
基础医学   4659篇
口腔科学   1076篇
临床医学   2502篇
内科学   8241篇
皮肤病学   943篇
神经病学   2531篇
特种医学   1415篇
外科学   6130篇
综合类   198篇
一般理论   2篇
预防医学   1328篇
眼科学   740篇
药学   2609篇
中国医学   45篇
肿瘤学   3786篇
  2023年   167篇
  2022年   371篇
  2021年   686篇
  2020年   401篇
  2019年   548篇
  2018年   668篇
  2017年   606篇
  2016年   636篇
  2015年   719篇
  2014年   919篇
  2013年   1187篇
  2012年   1676篇
  2011年   1785篇
  2010年   1044篇
  2009年   904篇
  2008年   1568篇
  2007年   1557篇
  2006年   1561篇
  2005年   1637篇
  2004年   1494篇
  2003年   1481篇
  2002年   1388篇
  2001年   1325篇
  2000年   1358篇
  1999年   1230篇
  1998年   404篇
  1997年   346篇
  1996年   314篇
  1995年   287篇
  1994年   248篇
  1993年   246篇
  1992年   830篇
  1991年   733篇
  1990年   739篇
  1989年   702篇
  1988年   714篇
  1987年   625篇
  1986年   618篇
  1985年   603篇
  1984年   398篇
  1983年   326篇
  1982年   151篇
  1979年   322篇
  1978年   208篇
  1977年   154篇
  1975年   149篇
  1974年   213篇
  1973年   152篇
  1972年   165篇
  1971年   147篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
Although dose reduction of S‐1 is recommended for patients with impaired renal function, dose modification for such patients has not been prospectively evaluated. The aim of the present study was to investigate the pharmacokinetic parameters of 5‐fluorouracil, 5‐chloro‐2,4 dihydroxypyridine and oteracil potassium, and to review the recommended dose modification of S‐1 in patients with renal impairment. We classified patients receiving S‐1 into 4 groups according to their renal function, as measured using the Japanese estimated glomerular filtration rate (eGFR) equation. The daily S‐1 dose was adjusted based on the patient's eGFR and body surface area. Blood samples were collected for pharmacokinetic analysis. A total of 33 patients were enrolled and classified into 4 groups as follows: 10 patients in cohort 1 (eGFR ≥ 80 mL/min/1.73 m2), 10 patients in cohort 2 (eGFR = 50‐79 mL/min/1.73 m2), 10 patients in cohort 3 (eGFR = 30‐49 mL/min/1.73 m2), and 3 patients in cohort 4 (eGFR < 30 mL/min/1.73 m2). Those in cohorts 3 and 4 treated with an adjusted dose of S‐1 showed a similar area under the curve for 5‐fluorouracil (941.9 ± 275.6 and 1043.5 ± 224.8 ng/mL, respectively) compared with cohort 2 (1034.9 ± 414.3 ng/mL). Notably, while there was a statistically significant difference between cohort 1 (689.6 ± 208.8 ng/mL) and 2 (= 0.0474) treated with an equal dose of S‐1, there was no significant difference observed in the toxicity profiles of the cohorts. In conclusion, dose adjustment of S‐1 in patients with impaired renal function using eGFR is appropriate and safe.  相似文献   
3.
4.
5.
6.
7.
8.
Purpose of the study: the aim of this study was to synthesize PFC fNIRS outcomes on the effects of cognitive tasks compared to resting/baseline tasks in healthy adults from studies utilizing a pre/post design.

Material and methods: original research studies were searched from seven databases (MEDLINE, EMBASE, CENTRAL, CINAHL, SCOPUS, PEDro and PubMed). Subsequently, two independent reviewers screened the titles and abstracts followed by full-text reviews to assess the studies' eligibility.

Results: eleven studies met the inclusion criteria and had data abstracted and quality assessed. Methodology varied considerably and yet cognitive tasks resulted in the ΔO2Hb increasing in 8 of the 11 and ΔHHb decreasing in 8 of 8 studies that reported this outcome. The cognitive tasks from 10 of the 11 studies were classified as “Working Memory” and “Verbal Fluency Tasks”.

Conclusions: although, the data comparison was challenging provided the heterogeneity in methodology, the results across studies were similar.  相似文献   

9.
10.

Background

Controversy continues as to whether single-incision laparoscopic cholecystectomy, with the somewhat larger incision at the umbilicus, may lead to a worse postoperative quality of life and more pain compared with the more classic 4-port laparoscopic cholecystectomy. The aim of this study was to compare single-incision and 4-port laparoscopic cholecystectomy from the perspective of quality of life.

Methods

This study was a multicenter, parallel-group, open-label, randomized clinical trial. A total of 120 patients who were scheduled to undergo elective cholecystectomy were randomly assigned 1:1 into the single-incision laparoscopic cholecystectomy or the 4-port laparoscopic cholecystectomy group and then assessed continuously for 2 weeks during the postoperative period. The primary outcome was quality of life, defined as the time to resume normal daily activities. Postoperative pain was also assessed. To explore the heterogeneity of treatment effects, we assessed the interactions of sex, age, and working status on recovery time.

Results

A total of 58 patients in the single-incision group and 53 in the 4-port group (n?=?111, 47 male, mean age 57 years) were analyzed. The mean time to resume daily activities was 10.2 days and 8.8 days, respectively, for single-incision and 4-port laparoscopic cholecystectomy (95% confidence interval –0.4 to 3.2, P?=?.12). Similarly, the time to relief from postoperative pain did not differ significantly between the groups. Statistically insignificant but qualitative interactions were noted; in the subgroups of women, full-time workers, and patients younger than 60 years, recovery tended to be slower after single-incision laparoscopic cholecystectomy.

Conclusion

Postoperative quality of life did not differ substantially between single-incision laparoscopic cholecystectomy and 4-port laparoscopic cholecystectomy. Patients younger than 60 years, women, and full-time workers tended to have a somewhat slower recovery after single-incision laparoscopic cholecystectomy.  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