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   531432篇
  免费   27730篇
  国内免费   504篇
耳鼻咽喉   6711篇
儿科学   16970篇
妇产科学   12547篇
基础医学   92799篇
口腔科学   12378篇
临床医学   48655篇
内科学   95771篇
皮肤病学   11906篇
神经病学   34144篇
特种医学   19771篇
外国民族医学   53篇
外科学   78279篇
综合类   7614篇
现状与发展   2篇
一般理论   108篇
预防医学   38658篇
眼科学   11956篇
药学   41536篇
  1篇
中国医学   1134篇
肿瘤学   28673篇
  2019年   3925篇
  2018年   5764篇
  2017年   4150篇
  2016年   4890篇
  2015年   5396篇
  2014年   7158篇
  2013年   10557篇
  2012年   15660篇
  2011年   17477篇
  2010年   10002篇
  2009年   8870篇
  2008年   15784篇
  2007年   17522篇
  2006年   16996篇
  2005年   16328篇
  2004年   15965篇
  2003年   15343篇
  2002年   14870篇
  2001年   22483篇
  2000年   23038篇
  1999年   18982篇
  1998年   5249篇
  1997年   4382篇
  1996年   4414篇
  1995年   4138篇
  1992年   14437篇
  1991年   15826篇
  1990年   15965篇
  1989年   15640篇
  1988年   14322篇
  1987年   14209篇
  1986年   13179篇
  1985年   12691篇
  1984年   9402篇
  1983年   8002篇
  1982年   4181篇
  1979年   8943篇
  1978年   6388篇
  1977年   5151篇
  1976年   5507篇
  1975年   6613篇
  1974年   7423篇
  1973年   7163篇
  1972年   6597篇
  1971年   6310篇
  1970年   5888篇
  1969年   5467篇
  1968年   5161篇
  1967年   4621篇
  1966年   3964篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
52.
OBJECTIVE: This study was conducted to compare an otolaryngologist's experience with a cohort of epilepsy patients implanted with a vagal nerve stimulator (VNS) to previously published data. METHODS: Demographics, preoperative seizure frequency, medications, and complications were retrospectively collected from patients implanted by the senior author. Postoperative medications and seizure frequency were obtained from referring neurologists. RESULTS: Seventeen patients were implanted over a 24-month period. Average age was 28.3 years. Patients presented with petit mal (n = 3), tonic-clonic (n = 6), complex partial (n = 5), and grand mal (n = 8) seizures. Mean follow-up postimplantation was 13.5 months. Most patients had at least a 50% reduction of seizure frequency, with 3 patients being seizure free. There were no postoperative infections. One patient had left vocal cord immobility. The most common side effect was voice disturbance during device activation. CONCLUSION: Otolaryngologists are well equipped to perform VNS implantation and to diagnose and treat possible laryngeal side effects. EBM rating: C-4.  相似文献   
53.
A rapid procedure for determining angiotensin II in the blood by inverse voltammetry using a TA-2 device (Tekhnoanalit Company, Tomsk) with a graphite electrode has been developed. The results of analyses using the proposed technique agree with the clinical data. The rapid analytical procedure favors optimization of cardiotropic drug therapy. __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 40, No. 12, pp. 54–56, December, 2006.  相似文献   
54.
55.
56.
The purposes of this study were to examine how hospital patients' backgrounds and clinical illness are related to their perceptions of the individualized care they receive and to test the sensitivity of the Individualized Care Scale (ICS). Cross-sectional explorative survey data were obtained using questionnaires completed by 861 (response rate = 88%) predischarge hospital patients from six hospitals in Southern Finland in 2004. Self-administered questionnaires included the ICS as well as the 15D, a measure of health-related quality of life, and gathered information about the patients' backgrounds. Based on association tests, younger age, poorer state of health, and higher level of education were associated with more critical perceptions of individualized care. Using simultaneous regression analysis and presenting the results from stronger to weaker, we found age to be the strongest predictor of patients' positive perceptions of the individualized care they received. This was followed by health-related quality of life (HRQoL) as measured by the 15D, vocational education, and type of admission. The ICS was found to be a valid tool for the measurement of individualized care in hospitals. The self-reported patient data from this survey suggest that some patient characteristics are associated with the patients' perceptions about the individualized care they receive. There is now a need to consider how these characteristics can be taken into account in nursing care delivery to increase individualized care for hospital patients. The results also support use of the ICS in the measurement of individualized care in hospitals.  相似文献   
57.
Conclusions Limitation of this analysis is participation of limited centers. Though all the regions of the country are represented total number of procedures reported are less. Isolated CABG is commonest procedure performed in 2004. Congenital surgical procedures are more than the valvular heart disease procedure. For appropriate categorization we need standard nomenclature for various congenital surgical procedures.  相似文献   
58.
59.
OBJECTIVES: to examine the management and outcome of patients with traumatic popliteal artery pseudoaneurysms with delayed presentation. MATERIALS: over a 2-year period 7 patients with traumatic popliteal pseudoaneurysms presenting to a tertiary referral unit after a delay of 1 month were reviewed. METHODS: a retrospective review of clinical records. RESULTS: the median interval between injury and presentation was 1.5 months (range 1-24 months). Penetrating trauma from gunshot wounds was the cause of the initial vascular injury in 6 patients and a stab wound in one. All patients had large pseudoaneurysms of more than 8 cm filling the popliteal fossa with variable degrees of fixed flexion deformity (FFD) of the knee. Severe FFD of more than 40 degrees was noted in 2 patients and 3 others had mild flexion deformities of 10 to 20 degrees. Six patients underwent repair of the pseudoaneurysm. One patient required an above knee amputation due to an infected false aneurysm. There were no deaths or graft related complications. Despite aggressive post-operative physiotherapy only 2 patients were able to completely straighten the leg at the time of discharge. CONCLUSIONS: in patients with neglected popliteal artery pseudoaneurysms, morbidity is associated with the pre-operative degree of fixed flexion deformity of the knee.  相似文献   
60.
V Frecer  S Miertus 《Neoplasma》1988,35(5):525-538
A mechanistic QSAR study on N-nitrosamines (NA) was performed with the aid of the semiempirical MINDO/3 method. Both the chemical reactivity and the transport in biological medium were taken into account. The parent NA molecules and their first reaction intermediates in the metabolic activation pathway were examined for possible determinants of the relative carcinogenic potency. The correlations found support the previous suggestions concerning the metabolic C alpha radical hydroxylation of NA. The role of transport properties in the early stage of NA biotransformation was also demonstrated.  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