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   1646831篇
  免费   126422篇
  国内免费   3651篇
耳鼻咽喉   21956篇
儿科学   54954篇
妇产科学   47803篇
基础医学   237122篇
口腔科学   43757篇
临床医学   145940篇
内科学   327345篇
皮肤病学   38423篇
神经病学   133441篇
特种医学   62992篇
外国民族医学   501篇
外科学   247831篇
综合类   38783篇
现状与发展   4篇
一般理论   612篇
预防医学   126229篇
眼科学   37281篇
药学   115792篇
  35篇
中国医学   3918篇
肿瘤学   92185篇
  2021年   12742篇
  2019年   13330篇
  2018年   19244篇
  2017年   14651篇
  2016年   16596篇
  2015年   18565篇
  2014年   26003篇
  2013年   38955篇
  2012年   52158篇
  2011年   55146篇
  2010年   32923篇
  2009年   31257篇
  2008年   50916篇
  2007年   54093篇
  2006年   54564篇
  2005年   52820篇
  2004年   50501篇
  2003年   48077篇
  2002年   46270篇
  2001年   82744篇
  2000年   84573篇
  1999年   70029篇
  1998年   19388篇
  1997年   17585篇
  1996年   17610篇
  1995年   16729篇
  1994年   15233篇
  1993年   14300篇
  1992年   52299篇
  1991年   50195篇
  1990年   48215篇
  1989年   46138篇
  1988年   42125篇
  1987年   41105篇
  1986年   38353篇
  1985年   36673篇
  1984年   27771篇
  1983年   23403篇
  1982年   14240篇
  1981年   12473篇
  1979年   24446篇
  1978年   17313篇
  1977年   14437篇
  1976年   13509篇
  1975年   14086篇
  1974年   16904篇
  1973年   16428篇
  1972年   15365篇
  1971年   14007篇
  1970年   13408篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
941.
Choosing the best way to approach adrenal gland and retroperitoneal tumours is still difficult. We reviewed our first 10 cases operated on by retroperitoneoscopy and compared this approach with other possible ways described in the literature. There were 2 intraoperative complications: 1 opening of the diaphragm and 1 bleeding. Tumour resection was always complete. There was no conversion. There were no postoperative complications. The retroperitoneoscopic approach for adrenalectomy and retroperitoneal tumour resection is increasingly being used. In children, operation is quite fast, without much blood loss and with spectacular postoperative recovery results. Even for the right side we advocate this approach, due to the particular anatomy (small tumour size, less fat, thinner muscle layers) in this age group. Trained surgeons are, of course, mandatory.  相似文献   
942.
Background: Dreaming reported after anesthesia remains a poorly understood phenomenon. Dreaming may be related to light anesthesia and represent near-miss awareness. However, few studies have assessed the relation between dreaming and depth of anesthesia, and their results were inconclusive. Therefore, the authors tested the hypothesis that dreaming during anesthesia is associated with light anesthesia, as evidenced by higher Bispectral Index values during maintenance of anesthesia.

Methods: With approval, 300 consenting healthy patients, aged 18-50 yr, presenting for elective surgery requiring relaxant general anesthesia with a broad range of agents were studied. Patients were interviewed on emergence and 2-4 h postoperatively. The Bispectral Index was recorded from induction until the first interview. Dream content and form were also assessed.

Results: Dreaming was reported by 22% of patients on emergence. There was no difference between dreamers and nondreamers in median Bispectral Index values during maintenance (37 [23-55] vs. 38 [20-59]; P = 0.68) or the time at Bispectral Index values greater than 60 (0 [0-7] vs. 0 [0-31] min; P = 0.38). Dreamers tended to be younger and male, to have high home dream recall, to receive propofol maintenance or regional anesthesia, and to open their eyes sooner after surgery. Most dreams were similar to dreams of sleep and were pleasant, and the content was unrelated to surgery.  相似文献   

943.
Unicompartmental knee arthroplasty (UKA) is considered the treatment of choice in patients with single compartment arthritis of the knee at early stages or with osteonecrosis limited to one compartment. However, results in the literature are still controversial and it is a technically difficult procedure. The main goal of UKA is to restore the articular space of the afflicted compartment, without influencing the limb alignment. Selection of patients and pre-operative planning are crucial. The necessity to improve functional results and to reduce immobilization of the patients has led to the development of minimally invasive surgery. Applied to UKA, this approach reduces blood loss and surgical time, causes fewer symptomatic postoperative complications, and permits earlier recovery compared to the traditional incision. The shorter incision makes careful pre-operative planning essential. We briefly review the indications for UKA, the pre-operative clinical and radiological assessment, and the surgical procedure. Proocedings of the Consensus Conference “TSS in hip and knee replacement” (Rapallo, Italy 22–24 June 2006)  相似文献   
944.
945.
Background: Gabapentin has been reported to inhibit various acute and chronic pain conditions in animals and humans. Although the efficacy of gabapentin depends on the [alpha]2[delta] subunit of voltage-gated calcium channels, its analgesic mechanisms in vivo are still unknown. Here, the authors tested the role of spinal noradrenergic inhibition in gabapentin's analgesia for postoperative pain.

Methods: Gabapentin was administered orally and intracerebroventricularly to rats on the day after paw incision, and withdrawal threshold to paw pressure was measured. The authors also measured cerebrospinal fluid concentration of norepinephrine and postoperative morphine use after surgery in patients who received oral placebo or gabapentin.

Results: Both oral and intracerebroventricular gabapentin attenuated postoperative hypersensitivity in rats in a dose-dependent manner. This effect of gabapentin was blocked by intrathecal administration of the [alpha]2-adrenergic receptor antagonist idazoxan and the G protein-coupled inwardly rectifying potassium channel antagonist tertiapin-Q, but not by atropine. In humans, preoperative gabapentin, 1,200 mg, significantly increased norepinephrine concentration in cerebrospinal fluid and decreased morphine requirements.  相似文献   

946.
Accurate images of the craniofacial region are critical for the development of an orthodontic diagnosis and treatment plan. The NewTom QR 9000 Volume Scanner (QR s.r.l., Verona, Italy) represents a significant advance in imaging capabilities for dentistry and orthodontics. This new-generation scanner uses computed tomography technology to provide a complete 3D view of the maxilla and mandible with relatively high resolution and low radiation exposure to patients. This article discusses some technical aspects of this new scanner and its possible orthodontic uses.  相似文献   
947.
948.
Arteriovenous (AV) fistulas are common in renal cell carcinoma. These are usually small and asymptomatic. Case reports have previously described symptomatic fistulas in primary renal cell tumour or, less commonly, bone metastases. The current study describes a patient with lung metastases from renal cell carcinoma who developed a symptomatic pulmonary AV fistula. The patient presented with debilitating progressive shortness of breath, which resolved after coiling of the pulmonary AV fistula. Supporting radiographs include a unique ventilation-perfusion finding of perfusion tracer in the kidney that is diagnostic of a pulmonary shunt. This is the first report of a pulmonary fistula from renal cell carcinoma. This rare complication of renal cell carcinoma reflects its diverse clinical presentations and unique tumour biology.  相似文献   
949.
950.
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