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   1269310篇
  免费   86718篇
  国内免费   6284篇
耳鼻咽喉   17544篇
儿科学   36495篇
妇产科学   35589篇
基础医学   176432篇
口腔科学   36091篇
临床医学   105724篇
内科学   256088篇
皮肤病学   27076篇
神经病学   97326篇
特种医学   49698篇
外国民族医学   413篇
外科学   199182篇
综合类   33365篇
现状与发展   18篇
一般理论   331篇
预防医学   83488篇
眼科学   29543篇
药学   95438篇
  56篇
中国医学   6206篇
肿瘤学   76209篇
  2021年   9928篇
  2019年   9829篇
  2018年   14166篇
  2017年   11351篇
  2016年   11835篇
  2015年   13734篇
  2014年   19120篇
  2013年   27542篇
  2012年   37280篇
  2011年   39093篇
  2010年   24178篇
  2009年   22768篇
  2008年   36620篇
  2007年   38809篇
  2006年   38661篇
  2005年   37226篇
  2004年   35186篇
  2003年   34013篇
  2002年   33100篇
  2001年   66249篇
  2000年   68069篇
  1999年   57206篇
  1998年   14812篇
  1997年   13052篇
  1996年   12558篇
  1995年   11595篇
  1994年   10938篇
  1993年   10131篇
  1992年   42469篇
  1991年   40222篇
  1990年   39042篇
  1989年   37848篇
  1988年   34805篇
  1987年   33934篇
  1986年   32211篇
  1985年   30448篇
  1984年   22072篇
  1983年   18570篇
  1982年   10576篇
  1979年   19628篇
  1978年   13293篇
  1977年   11392篇
  1976年   10214篇
  1975年   11413篇
  1974年   13542篇
  1973年   12856篇
  1972年   12280篇
  1971年   11520篇
  1970年   10936篇
  1969年   10404篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
83.
French asthma patients may be supervised by general practitioners (GPs) and/or specialists. Therefore, this study examined asthma management in patients exclusively supervised by specialists (SPE), GPs, (GP) and both (GP+SPE group), and compared the findings. Asthma patients were consecutively recruited in 348 pharmacies. Each patient completed a questionnaire providing data on personal characteristics, asthma management, perception of disease and asthma supervision. Asthma control was measured using the Asthma Control Test. Questionnaires were linked to computerised records of medications which had been dispensed before inclusion in the study. From the 1,256 patients (mean age = 36.1 yrs, 54.3% females), 11.4, 36.6, and 52.0% were placed in the SPE, GP, and GP+SPE groups, respectively. During the previous 4 weeks, most patients in the SPE group were properly controlled (52.2 versus 26.4 and 21.5% in GP and GP+SPE groups, respectively). The SPE group made more use of fixed combinations of long-acting beta agonist and inhaled corticosteroid, while receiving less short-acting beta agonists, antitussives and antibiotics. Striking differences in symptoms and asthma management were observed according to the type of asthma supervision. The current results strongly support the need to improve the management of asthma in primary care, and the coordination of care between general practitioners and specialists.  相似文献   
84.
85.
86.
87.
OBJECTIVE: A safe entry zone to tegmental lesions was identified based on intraoperative electrophysiological findings, the compound muscle action potentials (CMAP) from the extraocular muscles, and anatomic considerations. This entry zone is bordered caudally by the intramesencephalic path of the trochlear, laterally by the spinothalamic tract, and rostrally by the caudal margin of the brachium of the superior colliculus. METHODS: Four intrinsic midbrain lesions were operated upon via the safe entry zone using the infratentorial paramedian supracerebellar approach. All lesions involved the tegmentum and included an anaplastic astrocytoma, a metastatic brain tumor, a radiation necrosis, and a cavernous angioma. CMAP were bilaterally monitored from the inferior recti (for oculomotor function) and superior oblique (for trochlear nerve function) muscles. RESULTS: In three of four cases, CMAP related to the oculomotor nerve were obtained upon stimulation at the cavity wall after removal of the tumor. Stimulation at the surface of the quadrigeminal plate, however, did not cause any CMAP response. Using this monitoring as an indicator, the lesions were totally removed. CONCLUSIONS: In the surgery of tegmental lesions, CMAP monitoring from extraocular muscles is particularly helpful to prevent damage to crucial neural structures during removal of intrinsic lesions, but less so to select the site of the medullary incision. The approach via the lateral part of the colliculi is considered to be a safe route to approach the tegmental lesions.  相似文献   
88.
Our group have studied a patient affected by a malignant schwannoma in the posterior tibial nerve. Schwannomas are uncommon neoplasms that originate from the Schwann cells of the peripheral nerves: the most common forms are benign. Malignant transformation is rarer. The therapy is surgical and the operation undertaken, if possible, should be the amputation. Alternatively, where amputation is not possible due to the specific localisation or due to patient refusal, the alternative must be the largest and most radical excision possible.  相似文献   
89.
Inter-individual variations in the development of silicosis, even within the same environments, have been reported, which suggest the contribution of genetic factors in silicosis aetiology. The aim of the present study was to determine whether there is any significant genetic influence on the development of silicosis. Furthermore, which genetic loci are responsible for the pulmonary response to silica exposure? Eight strains of inbred mice were used to examine the genetic influence on the lung fibrotic response to silica exposure. After intercross-breeding between the most susceptible and most resistant strains, a genome-wide linkage analysis of quantitative trait loci (QTL) was performed. Hydroxyproline was applied as an index, and genotypes of 167 marker genes were analysed by fragment analysis using a capillary-type sequencer. There was significant inter-strain difference in the mean concentration of hydroxyproline contents among the eight strains of mice. Breeding studies were conducted between the most susceptible, C57BL/6J, and the most resistant strain, CBA/J. A genome-wide linkage analysis of silica-exposed intercrossed cohorts identified significant QTL on chromosome 4 and suggestive QTL on chromosomes 3 and 18. The present study demonstrates that genetic factors may play a significant role in fibrotic-lung responses to silica; one significant and two suggestive quantitative trait loci were identified.  相似文献   
90.
AIMS: To establish all-cause and cause-specific death rates, and risk factors for mortality in insulin-treated diabetic individuals living in the province of Canterbury, New Zealand. METHODS: Insulin-treated diabetic subjects (n = 995) on the Canterbury Diabetes Registry were followed up over 15 years and vital status determined. Death rates were standardized and hazard regression was used to model the effects of demographic covariates on relative survival time. RESULTS: There were 419 deaths in 11 226.3 person-years of follow-up with a standardized mortality ratio (SMR) of 2.0 (95% confidence interval (CI) 1.8-2.2). Relative mortality was greatest for the group aged 0-29 years (SMR 3.0 (95% CI 2.4-3.7)). After controlling for diabetes duration and gender, a 10-year increment in age of onset was associated with a 33% decrease in relative hazard (95% CI 29-36%), indicating that excess mortality due to diabetes declines with rising age of onset. After controlling for age of onset and gender, each 10-year increment in duration of diabetes is associated with a 26% decrease in relative hazard (95% CI 24-29%), indicating that with longer survival the mortality hazard approaches the general population hazard. Relative mortalities were increased for cardiovascular, renal and respiratory disease, but not malignancy. Relative mortality from acute metabolic complications was increased in the subgroup with age of onset of diabetes < 30 years and requiring insulin within 1 year of diagnosis. CONCLUSIONS: Mortality rates are high for insulin-treated diabetic individuals relative to the general population.  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