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   522284篇
  免费   33936篇
  国内免费   625篇
耳鼻咽喉   6934篇
儿科学   17228篇
妇产科学   13682篇
基础医学   85903篇
口腔科学   15089篇
临床医学   45051篇
内科学   95027篇
皮肤病学   12250篇
神经病学   36975篇
特种医学   18846篇
外国民族医学   65篇
外科学   78463篇
综合类   8567篇
一般理论   123篇
预防医学   39616篇
眼科学   12356篇
药学   41048篇
中国医学   1008篇
肿瘤学   28614篇
  2018年   5051篇
  2015年   4598篇
  2014年   6205篇
  2013年   9775篇
  2012年   13151篇
  2011年   14624篇
  2010年   8504篇
  2009年   7972篇
  2008年   14052篇
  2007年   15050篇
  2006年   15303篇
  2005年   14699篇
  2004年   14407篇
  2003年   13675篇
  2002年   13555篇
  2001年   24315篇
  2000年   25322篇
  1999年   20767篇
  1998年   5505篇
  1997年   4784篇
  1996年   5125篇
  1995年   4700篇
  1994年   4379篇
  1993年   4191篇
  1992年   15929篇
  1991年   16495篇
  1990年   16611篇
  1989年   16001篇
  1988年   14756篇
  1987年   14615篇
  1986年   13765篇
  1985年   13128篇
  1984年   9776篇
  1983年   8346篇
  1982年   4627篇
  1981年   4293篇
  1979年   9547篇
  1978年   6959篇
  1977年   5855篇
  1976年   5703篇
  1975年   6493篇
  1974年   7734篇
  1973年   7245篇
  1972年   7054篇
  1971年   6760篇
  1970年   6245篇
  1969年   5943篇
  1968年   5622篇
  1967年   5065篇
  1966年   4493篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
992.
Although cardiac arrhythmias remain a serious clinical problem in many patients with heart disease, the exact role of antiarrhythmic drug therapy is currently under intense evaluation. Within the last several years it has become clear that there are significant risks as well as potential benefits associated with existing agents. Ongoing studies in large patient populations should help determine the benefit/risk ratio of traditional therapy. Regardless of the outcome of these trials, current electrophysiological dogma will have to be re-evaluated and newer concepts evolve for drug development to make further progress. The goal of this symposium is to exchange information among basic and clinical investigators so as to facilitate the emergence of novel electrophysiological concepts that will form the basis for future generations of antiarrhythmic drugs.  相似文献   
993.
994.
At the burn centre in Donetsk, from 1979 to 1988, 236 sufferers with a III-IV degree frostbite of the extremities were treated. Operated on were 189 patients, who underwent necrectomy, amputation of the extremity and different types of skin plasty. Of these patients, 49.8% were recognized as invalids. After 1-10 years, all the patients after a III-IV degree frostbite of the extremities make complaints, require different types of treatment, 38.9%--the operative one. For timely and qualitative rehabilitation of this category of the sufferers, their prophylactic medical examination is necessary.  相似文献   
995.
On the basis of their clinical experience in the treatment of 146 patients with congenital dislocation of the hip the authors have evaluated the state of the limb in this pathologic condition. Various changes in the limb's form have been observed depending on the expression of the hip dislocation and on the patient's age. The instruments for incisions and for correcting the limb's position have been worked out. The fixation of the limb in the functionally correct position is carried out by stitching its fragments and fixing the strained threads in the greater trochanter area. The correction of the limb's position allows the subsequent correct development of the acetabular roof.  相似文献   
996.
The article deals with the results of complex study of the effect of pulmonary insufficiency on intracardiac hemodynamics and function of the heart in the immediate and late-term periods after radical correction of Fallot's tetralogy. Answers are also given to questions concerning the expediency of the use and functional adequacy of a xeno-pericardial monocusp in the closure mechanism of the pulmonary artery valve. The study showed that massive pulmonary regurgitation has a negative effect on the functional condition of the right ventricle in late-term postoperative periods. Convincing data were obtained which allow a graft with a monocusp of a bull's pericardium to be recommended for further clinical use to prevent insufficiency of the pulmonary artery valve after radical correction of Fallot's tetralogy.  相似文献   
997.
998.
Mercury exposure of different origins among dentists and dental nurses   总被引:2,自引:0,他引:2  
Mercury exposure was studied among dental personnel with the use of urinary mercury excretion rates and questionnaires. The study covered 314 dentists and dental nurses employed in public clinics and private practices in Stockholm. The obtained urinary mercury excretion rates were analyzed by stepwise regression for assigning them to different origins, such as environmental factors, number of amalgam surfaces, chewing of gum, kind of employment and profession, age, sex, amalgam handling time, and use of amalgam capsules. On the average the occupational contribution to the total urinary mercury excretion rate was small and of the same order as the contribution from their own amalgam fillings (approximately 2 micrograms of mercury/24 h). There were, however, individuals showing excretion rates close to the levels at which effects on the central nervous system and the kidneys have been reported.  相似文献   
999.
1000.
The purpose of this study was to examine the possible influence of the phases of the menstrual cycle on dermal reactivity to skin-prick testing. We studied 15 atopic, menstruating women with seasonal rhinoconjunctivitis and/or asthma, with known sensitivity to olive and parietaria (mean age 25.2 years) and 15 non-atomic, healthy, female controls (mean age 24.7 years). Skin-prick tests with histamine, morphine, and in the atopic group with parietaria/and/or olive, were repeated three times during the same menstrual cycle, corresponding to bleeding (day 1–4), midcycle (day 12–16) and the late progesterone phase (day 24–28). None of the patients had received oral antihistamines or exogenous hormones for at least 1 month prior to testing. Results indicate a significant increase in weal-and-flare size to histamine, morphine, and parietaria on days 12–16 of the cycle, corresponding to ovulation and peak oestrogen levels. This was observed in both atopic and non-atopic women. Differences in skin reactivity to histamine and morphine between the groups were not significant. Therefore, in women, the phase of the menstrual cycle is another factor that may influence skin-test results.  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