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   2349866篇
  免费   171613篇
  国内免费   3331篇
耳鼻咽喉   32050篇
儿科学   75894篇
妇产科学   62686篇
基础医学   348172篇
口腔科学   63649篇
临床医学   211363篇
内科学   457303篇
皮肤病学   51727篇
神经病学   185270篇
特种医学   88008篇
外国民族医学   489篇
外科学   353861篇
综合类   47510篇
现状与发展   12篇
一般理论   848篇
预防医学   182730篇
眼科学   54329篇
药学   175104篇
  11篇
中国医学   4575篇
肿瘤学   129219篇
  2021年   18982篇
  2019年   19539篇
  2018年   27062篇
  2017年   20358篇
  2016年   22747篇
  2015年   25640篇
  2014年   36096篇
  2013年   53957篇
  2012年   74680篇
  2011年   79412篇
  2010年   47059篇
  2009年   44568篇
  2008年   74608篇
  2007年   79480篇
  2006年   80294篇
  2005年   77779篇
  2004年   74370篇
  2003年   71690篇
  2002年   69365篇
  2001年   108738篇
  2000年   111452篇
  1999年   93498篇
  1998年   26995篇
  1997年   23660篇
  1996年   24054篇
  1995年   22716篇
  1994年   20897篇
  1993年   19715篇
  1992年   72005篇
  1991年   70071篇
  1990年   68391篇
  1989年   65664篇
  1988年   60303篇
  1987年   59130篇
  1986年   55219篇
  1985年   53006篇
  1984年   39313篇
  1983年   33396篇
  1982年   19858篇
  1979年   35866篇
  1978年   25651篇
  1977年   21230篇
  1976年   20332篇
  1975年   21816篇
  1974年   26148篇
  1973年   24804篇
  1972年   23203篇
  1971年   22037篇
  1970年   20248篇
  1969年   19315篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
151.
The reliable change index (RCI) expresses change relative to its associated error, and is useful in the identification of post-operative cognitive dysfunction (POCD). This paper examines four common RCIs that each account for error in different ways. Three rules incorporate a constant correction for practice effects and are contrasted with the standard RCI that had no correction for practice. These rules are applied to 160 patients undergoing coronary artery bypass graft (CABG) surgery who completed neuropsychological assessments preoperatively and 1 week post-operatively using error and reliability data from a comparable healthy non-surgical control group. The rules all identify POCD in a similar proportion of patients, but the use of the within subject standard deviation, expressing the effects of random error, as an error estimate is a theoretically appropriate denominator when a constant error correction, removing the effects of systematic error, is deducted from the numerator in a RCI.  相似文献   
152.
153.
Safety and efficacy of botulinum toxin type A following long-term use   总被引:2,自引:0,他引:2  
Botulinum toxin serotype A (BoNT-A) has long heritage of use leading to confidence in its safety and efficacy. The application of BoNT-A does not lead to persistent histological changes in the nerve terminal or the target muscle. Clinical trials defined the safety and tolerability profile of BoNT-A across common therapeutic indications and showed an incidence of adverse events of approximately 25% in the BoNT-A-treated group compared with 15% in the control group. Focal weakness was the only adverse event to occur more often following BoNT-A treatment. Long-term BoNT-A administration has been assessed in various treatment settings, with the level and duration of BoNT-A efficacy response being maintained over repeated rounds of injection with no major safety concerns. The treatment of children with cerebral palsy often require long-term, repeated, multimuscle BoNT-A injections that lead to the administration of comparably higher toxin doses. Despite the high total body doses used, their distribution over multiple muscles and injection sites means that systemic side effects are rare. Recent formulation changes have reduced the incidence of antibody development following treatment with BOTOX®. These findings show long-term BoNT-A treatment to be both safe and efficacious for a wide variety of indications.  相似文献   
154.
To understand in situ behavior of osteocytes, we characterized a model of osteocytes in their native bone matrix and demonstrated real-time biologic activity of osteocytes while bending the bone matrix. Using 43 male Sprague-Dawley rats, dumbbell-shaped explants were harvested from stainless steel femoral implants after 6-12 weeks and incubated in culture medium or fixed. Sixteen specimens were used to determine bone volume density (BV/TV), volumetric bone mineral density (BMD) and histology for different implantation periods. Osteocyte viability was evaluated by L-lactate dehydrogenase (LDH) activity in 12 cultured explants. Confocal microscopy was used to assess tracer diffusion in three explants and changes in osteocyte pH of a mechanically loaded explant. From 6 to 12 weeks, explant BV/TV and volumetric BMD trended up 92.5% and 101%, respectively. They were significantly and highly correlated. Tissues were uniformly intramembranous and all bone cell types were present. Explants maintained LDH activity through culture day 8. Diffusion at 200 microM was limited to 1,209 Da. Explants appeared capable of reproducing complex bone biology. This model may be useful in understanding osteocyte mechanotransduction in the context of a physiologically relevant bone matrix.  相似文献   
155.
156.
We report the case of a patient with a 13-year history of pemphigus vulgaris (PV) treated with immunosuppressive agents, prednisone and mycophenolate mofetil who had developed lesions of Kaposi's sarcoma (KS) on a sole plaque of PV that had been previously treated with intralesional injections of steroids. The lesions were surgically removed and polymerase chain reaction (PCR) demonstrated human herpesvirus-8 (HHV-8) DNA. There were neither recurrences nor later dissemination of KS following gradual decrease of the immunosuppressive therapy. We suggest that the treatment with intralesional steroids may have influenced the local reactivation of a latent infection of the virus, determining the appearance of this localized KS.  相似文献   
157.
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   
158.
159.
Relationship-centered care reflects both knowing and feeling: the knowledge that physician and patient bring from their respective domains of expertise, and the physician’s and patient’s experience, expression, and perception of emotions during the medical encounter. These processes are conveyed and reciprocated in the care process through verbal and nonverbal communication. We suggest that the emotional context of care is especially related to nonverbal communication and that emotion-related communication skills, including sending and receiving nonverbal messages and emotional self-awareness, are critical elements of high-quality care. Although nonverbal behavior has received far less study than other care processes, the current review argues that it holds significance for the therapeutic relationship and influences important outcomes including satisfaction, adherence, and clinical outcomes of care.  相似文献   
160.
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