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   271373篇
  免费   7037篇
  国内免费   803篇
耳鼻咽喉   2208篇
儿科学   9494篇
妇产科学   5376篇
基础医学   29451篇
口腔科学   3721篇
临床医学   20009篇
内科学   52333篇
皮肤病学   2904篇
神经病学   25565篇
特种医学   12573篇
外国民族医学   23篇
外科学   42089篇
综合类   3960篇
一般理论   47篇
预防医学   23436篇
眼科学   4245篇
药学   17218篇
  3篇
中国医学   1148篇
肿瘤学   23410篇
  2023年   456篇
  2022年   1069篇
  2021年   1911篇
  2020年   1251篇
  2019年   1731篇
  2018年   23727篇
  2017年   18775篇
  2016年   20964篇
  2015年   2925篇
  2014年   3426篇
  2013年   4620篇
  2012年   12004篇
  2011年   26054篇
  2010年   22028篇
  2009年   14416篇
  2008年   23896篇
  2007年   26252篇
  2006年   5119篇
  2005年   6586篇
  2004年   8055篇
  2003年   8842篇
  2002年   7007篇
  2001年   3975篇
  2000年   4055篇
  1999年   3124篇
  1998年   1348篇
  1997年   1098篇
  1996年   916篇
  1995年   905篇
  1994年   800篇
  1993年   727篇
  1992年   1816篇
  1991年   1842篇
  1990年   1616篇
  1989年   1517篇
  1988年   1378篇
  1987年   1220篇
  1986年   1190篇
  1985年   1064篇
  1984年   788篇
  1983年   716篇
  1982年   473篇
  1980年   393篇
  1979年   570篇
  1978年   425篇
  1975年   433篇
  1974年   502篇
  1973年   464篇
  1972年   422篇
  1971年   393篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
Follicular fluids from eight patients with one ovary and from ten patients with two ovaries were investigated for bioactive inhibin, total renin, oestradiol (E2) and progesterone (P4) concentrations. Four follicular fluids were pooled per patient before assessment. All women had been stimulated similarly using a protocol including a GnRH agonist, HMG and HCG. Renin levels were significantly lower and P4 significantly higher in pools of follicular fluid from patients with one ovary, whereas inhibin and E2 concentrations were similar in both patient groups. A significant negative correlation was found in the pools of follicular fluid between inhibin and E2 in both groups. These results suggest a role for inhibin and renin in the paracrine and autocrine control of stimulated follicular development.  相似文献   
93.
94.
95.
Abstract We report a case of SMV injury in a critically ill patient. The patient was a 19-year-old woman involved in a motor vehicle collision. Her injuries included grade II splenic and renal lacerations, devascularized and lacerated right and transverse colon, a transected transverse mesocolon, a massive shear injury of her abdominal wall, and two partial SMV transections. At initial damage control laparotomy, the SMV was ligated, the devascularized bowel resected and a temporary abdominal closure applied. At re-operation, a mesocaval shunt using saphenous vein was employed. The shunt failed and the patient required a saphenous vein jump graft. Although visceral vascular injuries are rare, ligation of the SMV in a damage control situation is acceptable. This case study is the first to discuss appropriate treatment when interruption to a patient's collateral visceral venous drainage limits the surgeon’s ability to ligate. In these situations, bypass shunts may be successful.  相似文献   
96.
97.
98.
For persons battling HIV/AIDS a stable place to live may decide the length and quality of life itself. It is nearly impossible for a person on the streets to engage in a needed continuous AIDS treatment regimen when the very basic question of where that person will rest his or her head when darkness comes in just a few hours is unresolved. When danger lurks on the streets, when cold numbs the limbs, when tiredness overwhelms the mind, when fear breaks the spirit, a place to call home would make all the difference.  相似文献   
99.
100.
Abstract Objective: To define the diagnostic accuracy of clinical examination in patients with impaired consciousness or endotracheal intubation to detect pelvic ring fractures and to identify those with severe bleeding. Methods: Included in this prospective data collection with retrolective data analysis were a consecutive series of blunt trauma victims with either a Glasgow Coma Scale ≤ 13 or tracheal intubation. Clinical examination comprised testing for stability of the iliac wings. Results: From 784 subjects (injury severity score 23.3 ± 17.4) 93 patients (11.9%) were found to have a pelvic ring fracture. Clinical instability of the pelvic ring was found in 42 patients. There was only one false positive. Fifty-two fractures could not be identified by clinical examination, including nine fractures (17%) that required surgical fracture stabilization (sensitivity of clinical examination 44.1%). Seventeen fractures (18.3%) were associated with a blood loss larger than 20% of circulating blood volume. Sixteen of those were identified by clinical instability of the pelvic ring (sensitivity 94.1%, specificity 97.0%, positive predictive value 38.1%, negative predictive value 99.9%). Conclusions: Clinical examination for stability of the pelvis in this selected group of patients missed a significant number of pelvic ring fractures including fractures that require surgical stabilization. The finding of a clinically unstable identifies most of the patients with the pelvic ring fracture being a major source of bleeding. A stable pelvis makes pelvic ring fracture as being the source of bleeding quite unlikely.  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