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   13739篇
  免费   1062篇
  国内免费   43篇
耳鼻咽喉   82篇
儿科学   244篇
妇产科学   246篇
基础医学   1946篇
口腔科学   463篇
临床医学   1775篇
内科学   2770篇
皮肤病学   283篇
神经病学   1136篇
特种医学   590篇
外科学   1992篇
综合类   87篇
一般理论   2篇
预防医学   1208篇
眼科学   243篇
药学   850篇
中国医学   34篇
肿瘤学   893篇
  2023年   81篇
  2022年   75篇
  2021年   221篇
  2020年   159篇
  2019年   222篇
  2018年   284篇
  2017年   260篇
  2016年   250篇
  2015年   240篇
  2014年   357篇
  2013年   528篇
  2012年   706篇
  2011年   758篇
  2010年   386篇
  2009年   346篇
  2008年   620篇
  2007年   632篇
  2006年   588篇
  2005年   514篇
  2004年   506篇
  2003年   451篇
  2002年   425篇
  2001年   364篇
  2000年   445篇
  1999年   383篇
  1998年   181篇
  1997年   158篇
  1996年   145篇
  1995年   142篇
  1994年   136篇
  1993年   119篇
  1992年   322篇
  1991年   337篇
  1990年   329篇
  1989年   275篇
  1988年   260篇
  1987年   292篇
  1986年   275篇
  1985年   217篇
  1984年   212篇
  1983年   196篇
  1982年   117篇
  1981年   95篇
  1979年   125篇
  1978年   90篇
  1977年   80篇
  1975年   78篇
  1974年   75篇
  1973年   81篇
  1970年   73篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Ordinary surgical rubber gloves are penetrated by methylmethacrylate monomer (MMA) in less than 1 minute, as demonstrated by gas chromatographic measurements. A three-layered PVP glove, 0.07 mm thick - consisting of an outer layer of polyethylene, an intermediary layer of ethylene vinyl alcohol copolymer, and an inner layer of polyethylene - was impervious for 20 minutes, whereas a viton-butyl rubber glove, 0.27 mm thick, was impervious for 15 minutes.

The PVP glove is recommended to orthopedic surgeons, nurses, and other handling acrylic bone cements to avoid sensitization, and is especially recommended to persons with known contact allergy to MMA.  相似文献   
22.
Incidence of colorectal cancer increasing exponentially with age is confirmed but sex-age differences in incidence throughout the large bowel are shown. Observations of incidence within countries indicate that colorectal cancer is a disease of affluent societies. Furthermore, it is hypothesized that a high dietary fat intake leads to an increase in faecal components associated with colon cancer risk.  相似文献   
23.
24.
25.
26.
This prospective randomized controlled outcome study was designed to evaluate whether a MultiModal Cognitive—Behavioral Treatment for chronic spinal pain (MMCBT) specifically designed for women has an increased effect on well being and return to work compared to a regular MMCBT regimen. In Sweden, spinal pain is most prevalent among women. A tremendous amount of money is spent on secondary prevention of spinal pain. Yet, little is known about the effect of the interventions. A need for well designed outcome studies exist. Fifty-four subjects from a cohort of all registered sick-listed women in three districts of Stockholm participated in the study. Subjects were allocated by central randomization into two groups. One group was treated with a regular MMCBT program and the other group with a MMCBT program specifically designed for women. Assessments were performed at pretreatment–posttreatment (last treatment day) and at 6 and 18 months posttreatment. Questionnaires covering the bio-psycho-social spectra of the chronic pain syndrome, and sick leave were used to measure outcome. Intention to treat and true to protocol analyses were performed. The only significant differences found between groups were improvements in self-reported disability and in coping with pain, favoring the experimental treatment. About one-third of the variance in disability was explained by the set of pain-coping strategies assessed in the study. The results do not lend sufficient statistical support to warrant acceptance of the experimental treatment as superior to the regular treatment in improving health and sick leave. Further investigation with larger groups is needed before a solid scientific conclusion can be drawn.  相似文献   
27.
E J Jensen  E Schmidt  B Pedersen    R Dahl 《Thorax》1990,45(11):831-834
Four hundred and ninety six smokers participated in a randomised comparison of the effect of silver acetate, nicotine, and ordinary chewing gum on smoking cessation. All were motivated to stop smoking abruptly and all had smoked at least 10 cigarettes a day for at least five years. Side effects and taste acceptability were related to outcome after six months. The participants attended nine meetings over a year, at which lectures, support, and advice about stopping smoking were given. Tobacco abstinence was confirmed by measurement of carbon monoxide in expired air. The chewing gums were used for 12 weeks. After 12 weeks there was a trend towards more abstainers in the nicotine group (59%) than in the silver acetate (50%) and ordinary (45%) chewing gum groups that was not quite significant (p = 0.07). At 26 and 52 weeks the number of cigarette abstainers was similar in the three treatment groups. Subjects in the nicotine chewing gum group had a longer mean time before relapse than those in the silver acetate and ordinary chewing gum groups. Mean success rates for all subjects combined at 12, 26, and 52 weeks were 52.8%, 39.7%, and 23.3%. The side effects of nicotine and silver acetate chewing gum were generally mild and transient, and unimportant except for mouth irritation from silver acetate, which had a negative effect on outcome, and the low taste acceptability of nicotine, which had a strong negative influence on the success rate. The results suggest a short term effect on nicotine chewing gum on smoking cessation, but the abstinence rates after one year were generally disappointing.  相似文献   
28.
Sixteen dogs had one tibia filled with acrylic PMMA bone cement and the opposite, control tibia filled with inert bone wax. After 1, 4, and 12 weeks, the blood perfusion in diaphyses was measured with Sc-46 labeled microspheres. The blood flow rates increased from 1 to 4 weeks and dropped to about the 1-week level after 12 weeks on both sides, with the acrylic side lower than the control side. On both sides, Disulphine Blue staining of the bones showed severe endosteal avascularity after 1 and 4 weeks and massive periosteal apposition after 4 and 12 weeks. The initial increase in blood flow is considered due to periosteal apposition, and the differences in blood flow rates are attributed to avascularity caused by the polymerization heat and toxicity of the acrylic cement.  相似文献   
29.
Background: Neuropathic pain in spinal cord injury is a common challenging therapeutic condition. The current study examines the analgesic effect of the sodium channel blocker lidocaine on neuropathic pain in patients with spinal cord injury and the predictive role of concomitant evoked pain on pain relief with lidocaine.

Methods: Twenty-four spinal cord injury patients with neuropathic pain at or below the level of injury were randomized and completed a double-blind crossover trial of 5 mg/kg lidocaine and placebo infused over 30 min. Twelve patients reported evoked pain, and 12 patients had no evoked pain. Spontaneous and evoked pains were assessed using a visual analog scale and quantitative sensory testing.

Results: Lidocaine significantly reduced spontaneous pain in all patients (P < 0.01) and in each of the two groups with (P < 0.01) and without (P = 0.048) evoked pain, with no difference in number of responders (pain reduction >= 33%) between the patients with (n = 6) and without (n = 5) evoked pain. Lidocaine significantly relieved both at-level and below-level neuropathic pain and decreased brush-evoked dysesthesia but not cold allodynia, pinprick hyperalgesia, or pain evoked by repetitive pinprick.  相似文献   

30.
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