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   208740篇
  免费   2923篇
  国内免费   106篇
耳鼻咽喉   1555篇
儿科学   8492篇
妇产科学   3660篇
基础医学   20849篇
口腔科学   2302篇
临床医学   14724篇
内科学   37526篇
皮肤病学   1488篇
神经病学   18190篇
特种医学   9651篇
外科学   33370篇
综合类   3623篇
一般理论   15篇
预防医学   20049篇
眼科学   4231篇
药学   12770篇
中国医学   898篇
肿瘤学   18376篇
  2023年   238篇
  2022年   671篇
  2021年   1165篇
  2020年   644篇
  2019年   870篇
  2018年   22747篇
  2017年   17891篇
  2016年   20273篇
  2015年   1855篇
  2014年   2107篇
  2013年   2456篇
  2012年   9218篇
  2011年   23207篇
  2010年   19993篇
  2009年   12587篇
  2008年   21074篇
  2007年   23225篇
  2006年   2210篇
  2005年   3459篇
  2004年   4657篇
  2003年   5424篇
  2002年   3409篇
  2001年   1073篇
  2000年   1261篇
  1999年   878篇
  1998年   499篇
  1997年   406篇
  1996年   306篇
  1995年   312篇
  1994年   269篇
  1993年   205篇
  1992年   532篇
  1991年   485篇
  1990年   548篇
  1989年   468篇
  1988年   407篇
  1987年   393篇
  1986年   370篇
  1985年   351篇
  1984年   280篇
  1983年   239篇
  1982年   163篇
  1979年   232篇
  1978年   156篇
  1977年   183篇
  1975年   176篇
  1974年   201篇
  1973年   183篇
  1972年   173篇
  1971年   161篇
排序方式: 共有10000条查询结果,搜索用时 156 毫秒
91.
92.
Allergic autoimmune reaction after exposure to heavy metals such as mercury may play a causal role in autism, a developmental disorder of the central nervous system. As metallothionein (MT) is the primary metal-detoxifying protein in the body, we conducted a study of the MT protein and antibodies to metallothionein (anti-MT) in normal and autistic children whose exposure to mercury was only from thimerosal-containing vaccines. Laboratory analysis by immunoassays revealed that the serum level of MT did not significantly differ between normal and autistic children. Furthermore, autistic children harboured normal levels of anti-MT, including antibodies to isoform MT-I (anti-MT-I) and MT-II (anti-MT-II), without any significant difference between normal and autistic children. Our findings indicate that because autistic children have a normal profile of MT and anti-MT, the mercury-induced autoimmunity to MT may not be implicated in the pathogenesis of autism.  相似文献   
93.
94.
95.
96.

Background  

Acromioclavicular injuries are common in sports medicine. Surgical intervention is generally advocated for chronic instability of Rockwood grade III and more severe injuries. Various methods of coracoclavicular ligament reconstruction and augmentation have been described. The objective of this study is to compare the biomechanical properties of a novel palmaris-longus tendon reconstruction with those of the native AC+CC ligaments, the modified Weaver-Dunn reconstruction, the ACJ capsuloligamentous complex repair, screw and clavicle hook plate augmentation.  相似文献   
97.
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   
98.
The abdominal compartment syndrome is a life threatening condition resulting from pathologic elevation of the intraabdominal pressure. Prompt diagnosis is required to avoid significant sequelae. Diagnosis of this syndrome is based on clinical findings and intra abdominal pressure monitoring. Treatment consists of decompressive laparotomy, which corrects the pathology. Various surgical techniques are described to manage the open abdomen. Despite considerable attention accorded to this disorder, it is still associated with high morbidity and mortality. This review article deals with the identification of risk factors, pathophysiology, diagnostic criteria and treatment of critically ill patients with the abdominal compartment syndrome.  相似文献   
99.
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   
100.
OBJECTIVES: This study sought to characterize epileptic phenotypes in children with nonspecific mitochondrial disease (MD) and to evaluate MD diagnostic approaches. METHODS: A retrospective analysis of the medical, electroencephalogram, and laboratory records of 142 patients with epilepsy was performed. The patients were evaluated for MD, and 124 patients were included in the final cohort. The MD criteria used included an oral glucose lactate stimulation test (OGLST) and urine organic acid/plasma amino acid (UOA/PAA) assays as metabolic indicators of modified Walker criteria, as suggested by Bernier et al. (Neurology 59:1406-1411, 2002). RESULTS: Twenty-two patients were classified as having definite MD (9), probable MD (5), possible MD (6), or pyruvate dehydrogenase (PDH) deficiency (3), including one patient which showed a respiratory chain (RC) defect and PDH deficiency. Seven out of eight patients in whom significant RC defects were observed showed complex I defects. In 14 patients, epileptic seizures start at infantile ages. Of 17 patients who substantially presented generalized seizures, 4 patients started with partial seizures. Five patients consistently presented only partial seizures. The OGLST and UOA/PAA assays were useful for a more precise diagnosis of MD, although low positive predictive value of the OGLST was regrettable. No patient was classified as definite MD by Walker's original criteria, but the use of our revised MD criteria resulted in the classification of nine additional patients as definite MD. CONCLUSIONS: MD manifested considerable diverse epileptic phenotypes and should be considered in the differential diagnosis of epilepsy in children with unexplained encephalomyopathy and progressive and fluctuating clinical courses.  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