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   171925篇
  免费   9853篇
  国内免费   444篇
耳鼻咽喉   2237篇
儿科学   5579篇
妇产科学   3602篇
基础医学   23296篇
口腔科学   7597篇
临床医学   12617篇
内科学   38501篇
皮肤病学   4371篇
神经病学   14346篇
特种医学   5419篇
外国民族医学   26篇
外科学   21084篇
综合类   1429篇
现状与发展   1篇
一般理论   61篇
预防医学   17914篇
眼科学   3181篇
药学   10489篇
中国医学   695篇
肿瘤学   9777篇
  2023年   889篇
  2022年   1949篇
  2021年   3637篇
  2020年   2446篇
  2019年   3459篇
  2018年   4847篇
  2017年   3646篇
  2016年   3391篇
  2015年   3967篇
  2014年   5441篇
  2013年   6893篇
  2012年   10692篇
  2011年   11180篇
  2010年   5688篇
  2009年   5109篇
  2008年   8653篇
  2007年   9288篇
  2006年   8576篇
  2005年   8869篇
  2004年   8347篇
  2003年   7638篇
  2002年   5684篇
  2001年   4980篇
  2000年   4989篇
  1999年   4373篇
  1998年   1586篇
  1997年   1319篇
  1996年   1305篇
  1995年   1100篇
  1994年   1103篇
  1993年   1005篇
  1992年   2674篇
  1991年   2579篇
  1990年   2359篇
  1989年   2361篇
  1988年   2134篇
  1987年   1975篇
  1986年   1848篇
  1985年   1774篇
  1984年   1270篇
  1983年   1027篇
  1982年   585篇
  1981年   525篇
  1980年   511篇
  1979年   931篇
  1978年   618篇
  1977年   498篇
  1975年   553篇
  1974年   550篇
  1973年   545篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
Transoesophageal echocardiography is a safe and rapid means of obtaining anatomical and dynamic information about the descending aorta. It was used to confirm a suspected diagnosis of ruptured descending aorta.  相似文献   
83.
Percutaneous nephrolithotomy (PCN) enables the urologist to remove upper urinary tract stones through a percutaneous nephrostomy tract. The principal advantages of PCN are the low morbidity, shortened hospital stay and rapid recovery. Percutaneous puncture failed in 5 (11%) of the first 44 patients with upper tract urolithiasis treated by PCN at Tygerberg Hospital. In 35 patients (80%) PCN cleared the kidney of stones but in 4 patients (9%) all stone fragments were not removed during the procedure. If the puncture and dilatation was successful, then 90% of patients were stone-free after PCN. Complications were minimal except for a diabetic who died of septicaemia. PCN is an alternative to open renal surgery in the management of most upper urinary tract stones. The technique is readily mastered by any urologist experienced in endoscopic surgery.  相似文献   
84.
85.
This research presents reports of cases where a biocompatible and alloplastic biomaterial—Bioplastique—was used, associated with conventional plastic surgery or as a complement to it, with the aim of achieving a better final aesthetic result. Four cases are presented where Bioplastique was used in association with rhytidoplasty, rhinoplasty, and other surgical techniques. This material has shown itself to be appropriate to complement surgery; achieving a final result which would not be possible without any resort to a complement or any other hard procedure by the surgeon and is not more traumatic for the patient.  相似文献   
86.
Contradictory results have been reported about the inhibitory input to the medial rectus subdivision of the oculomotor nucleus of the cat. In the present ultrastructural study, we quantified the GABAergic and glycinergic terminals in the various subdivisions of the rabbit oculomotor nucleus with the use of post-embedding immunocytochemistry combined with retrograde tracing of horseradish peroxidase. The density of the GABAergic input to the medial rectus subdivision was as substantial as that to the other subdivisions and the postsynaptic distribution of the GABAergic and glycinergic innervation did not differ among the different oculomotor subdivisions.  相似文献   
87.
88.
The pharmacokinetics of midazolam and its metabolites were studied in 17 patients on mechanical ventilation in a general intensive care unit who were receiving a continuous intravenous infusion of midazolam, adjusted according to the level of induced sedation. Three patients were studied twice. Serum midazolam and alpha-hydroxymidazolamglucuronide levels were determined during and after infusion. The sedation level was scored on a four-point scale. Half of the observed patients were still drowsy or asleep 10 hours after termination of midazolam infusion. In only one patient was midazolam serum elimination half-life less than 2 hours and in six patients the half-life was greater than 10 hours. A wide range of midazolam serum levels was associated with adequate sedation, and similarly the midazolam levels at the moment of awakening were highly variable. The serum concentration ratio of midazolam/alpha-hydroxymidazolamglucuronide at the end of the infusion varied from 0.03 to 15.6. Renal function could account for only a part of this variation.  相似文献   
89.
A 67-year-old man with non-insulin-dependent diabetes mellitus progressively developed, over a 2-year period, lower extremity sensory and motor defects associated with impaired bladder function and perineal and perianal sensation related to a disease of the conus medullaris extending from T12 to S5. The magnetic resonance imaging scan suggested myelomalacia and the diagnosis of progressive necrotic myelopathy was confirmed by surgical intervention.  相似文献   
90.
Dexenfluramine, an effective and safe serotoninergic drug with anorectic and possible food-selection-tuning properties, was investigated in a placebo-controlled study of 1 year's duration in severe and refractory obesity. The aim of the study was to assess weight loss, and changes in cardiovascular risk factors, food intake and eating behaviour. Dexfenfluramine- and placebo-treated patients achieved a similar weight loss (greater than 10% of initial weight, by 39.5 and 30.0%, greater than 20% of initial overweight by 42.1% and 32.5% and greater than 10 kg by 41.4 and 33.3%, respectively, of the initial cohorts). Furthermore, the decreases in weight (10.7 vs. 8.0 kg), in body mass index (3.9 vs. 2.9 kg m2) and in waist/hip ratio (0.04 vs. 0.02) were not significantly different. After discontinuation of the drug, the increase in weight (2.8 vs. 1.0 kg) was significantly higher in the dexfenfluramine-treated group. Except for a borderline better effect on glucose of dexfenfluramine, both groups showed similar beneficial changes in food intake and cardiovascular risk factors. Eating behaviour in response to emotional and external stimuli was comparable in the two groups, but placebo-treated patients had to restrain their eating more in order to achieve the same weight loss. Notwithstanding the fact that weight losses and an associated amelioration of health-risk factors were of similar magnitude in dexfenfluramine- and placebo-treated patients, dexfenfluramine might have a useful role in promoting a less stressed adherence to prolonged restriction of energy intake in the severe and refractory obese subject.  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