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   194466篇
  免费   38780篇
  国内免费   8167篇
耳鼻咽喉   3349篇
儿科学   3886篇
妇产科学   3256篇
基础医学   12057篇
口腔科学   6750篇
临床医学   37800篇
内科学   37095篇
皮肤病学   4110篇
神经病学   16560篇
特种医学   7391篇
外国民族医学   43篇
外科学   28068篇
综合类   20461篇
现状与发展   73篇
一般理论   6篇
预防医学   21418篇
眼科学   4188篇
药学   11734篇
  125篇
中国医学   7143篇
肿瘤学   15900篇
  2024年   1172篇
  2023年   6574篇
  2022年   5155篇
  2021年   7940篇
  2020年   9370篇
  2019年   5199篇
  2018年   10059篇
  2017年   10564篇
  2016年   10807篇
  2015年   12769篇
  2014年   16000篇
  2013年   17885篇
  2012年   12137篇
  2011年   12359篇
  2010年   13218篇
  2009年   14464篇
  2008年   9483篇
  2007年   7809篇
  2006年   8649篇
  2005年   6453篇
  2004年   4675篇
  2003年   4145篇
  2002年   3434篇
  2001年   3680篇
  2000年   2766篇
  1999年   3047篇
  1998年   2843篇
  1997年   2618篇
  1996年   2574篇
  1995年   2297篇
  1994年   1555篇
  1993年   1210篇
  1992年   1100篇
  1991年   964篇
  1990年   772篇
  1989年   741篇
  1988年   719篇
  1987年   563篇
  1986年   495篇
  1985年   421篇
  1984年   352篇
  1983年   374篇
  1982年   290篇
  1981年   257篇
  1980年   171篇
  1979年   120篇
  1978年   175篇
  1977年   151篇
  1976年   113篇
  1974年   110篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
13.
14.
15.
皮质发育障碍模型的建立及其致痫敏感性的研究   总被引:1,自引:0,他引:1  
目的:建立皮质发育障碍模型,探讨皮质发育障碍模型的敏感性。方法:在SD大鼠孕17d腹腔注入1,3-二氯乙烯-亚硝基脲(BCNU)制作皮质发育障碍模型;Nissl染色观察P60d仔鼠病理变化;选取P60d雄性仔鼠,腹腔注射氯化锂-毛果芸香碱,分别比较两组大鼠癫发生的潜伏期、持续状态时间和死亡率。结果:同龄仔鼠脑组织湿重实验组比对照组显著减轻(P<0.01);Nissl染色显示皮质变薄、皮质层次紊乱、海马区域异位细胞异常聚集;有皮质发育障碍的仔鼠注射氯化锂-毛果芸香碱后,癫发生的潜伏期显著缩短(P<0.01),癫持续状态时间延长(P<0.01),死亡率显著升高(P<0.05)。结论:BCNU致皮质发育障碍模型具有癫易感性。  相似文献   
16.
17.
Objective To investigate effect of reduced glutathione and diammonium glycyrrhizinate on the treatment of hepatic damage in experimental dogs following open abdominal injuries coupled with seawater immersion. Methods Twenty-four dogs with open abdominal injuries were randomly divided into 3 groups: the control group (given with simple observation after 1.5 h seawater immersion); the routine treatment group (given routine care and fluid transfusion after 1.5 h seawater immersion) ; the hepatic treatment group (given routine are, fluid transfusion and hepatic treatment as well, after 1.5 h seawater immersion). Each group consisted of 8 dogs. Blood samples were taken at different time points to measure total bilirubin (TB), alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), prothromin time (PT), endotoxin, tumor necrosis factor-α(TNF-α), interleukin-6 (IL-6), and pathological examination was also made at the same time. Results For the control group, contents of TB, ALT, AST and LDH increased significantly and survival time was less than 24 hours. Contents of TB, ALT, AST and LDH of the routine treatment group also increased significantly, but survival time of all the experimental animals was mere than 24 hours. Reduced glutathione and diammonium glycyrrhizinate could reduce the extent of lesion quite significantly 12~24 hours following open abdominal injuries. Conclusions Reduced glutathione and diammonium glycyrrhizinate seemed to have good effects on the treatment and prevention against hepatic damage induced by trauma coupled with seawater immersion. It could be used as a primary means for the treatment of such kind of hepatic damage.  相似文献   
18.
19.
The purpose of this study was to investigate radiographic measurements in a cohort of patients with juvenile hallux valgus (with a hallux valgus angle > 15 degrees ) using standardized weightbearing x-rays compared with an age-matched control group. First metatarsal protrusion distance, metatarsus primus adductus angle, metatarsus adductus, first metatarsal cuneiform angle, calcaneal inclination angle, and talocalcaneal angles were assessed with discriminant functional analysis. A total of 37 sets of data were analyzed from patients with a mean age of 13.45 +/- 1.75 years. The study identified 2 significant components of juvenile hallux valgus: a positive first metatarsal protrusion distance (P <.001) and metatarsal primus adductus angle (P = .002). Discriminant functional analysis was then used to determine the best predictors of juvenile hallux valgus. This analysis allowed only 1 variable, metatarsal protrusion distance, as a predictor of whether juvenile hallux valgus was present (P < .001), with 94.3% accuracy. This study showed that a positive metatarsal protrusion distance is a significant component of juvenile hallux valgus.  相似文献   
20.
CONTEXT: Although the nonmedical use of stimulant drugs such as cocaine and methamphetamine is increasingly common in many rural areas of the United States, little is known about the health beliefs of people who use these drugs. PURPOSE: This research describes illicit stimulant drug users' views on health and health-related concepts that may affect their utilization of health care services. METHODS: A respondent-driven sampling plan was used to recruit 249 not-in-treatment, nonmedical stimulant drug users who were residing in 3 rural counties in west central Ohio. A structured questionnaire administered by trained interviewers was used to collect information on a range of topics, including current drug use, self-reported health status, perceived need for substance abuse treatment, and beliefs about health and health services. FINDINGS: Participants reported using a wide variety of drugs nonmedically, some by injection. Alcohol and marijuana were the most commonly used drugs in the 30 days prior to the interview. Powder cocaine was used by 72.3% of the sample, crack by 68.3%, and methamphetamine by 29.7%. Fair or poor health status was reported by 41.3% of the participants. Only 20.9% of the sample felt they needed drug abuse treatment. Less than one third of the sample reported that they would feel comfortable talking to a physician about their drug use, and 65.1% said they preferred taking care of their problems without getting professional help. CONCLUSIONS: Stimulant drug users in rural Ohio are involved with a range of substances and hold health beliefs that may impede health services utilization.  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