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   3792篇
  免费   201篇
  国内免费   22篇
耳鼻咽喉   137篇
儿科学   95篇
妇产科学   38篇
基础医学   492篇
口腔科学   95篇
临床医学   211篇
内科学   964篇
皮肤病学   54篇
神经病学   443篇
特种医学   80篇
外科学   611篇
综合类   14篇
预防医学   105篇
眼科学   60篇
药学   277篇
中国医学   9篇
肿瘤学   330篇
  2023年   16篇
  2022年   51篇
  2021年   76篇
  2020年   39篇
  2019年   55篇
  2018年   64篇
  2017年   50篇
  2016年   45篇
  2015年   55篇
  2014年   72篇
  2013年   92篇
  2012年   164篇
  2011年   184篇
  2010年   102篇
  2009年   99篇
  2008年   175篇
  2007年   186篇
  2006年   160篇
  2005年   156篇
  2004年   163篇
  2003年   169篇
  2002年   138篇
  2001年   148篇
  2000年   166篇
  1999年   147篇
  1998年   52篇
  1997年   45篇
  1996年   45篇
  1995年   34篇
  1994年   28篇
  1993年   30篇
  1992年   102篇
  1991年   72篇
  1990年   86篇
  1989年   109篇
  1988年   84篇
  1987年   72篇
  1986年   67篇
  1985年   60篇
  1984年   43篇
  1983年   28篇
  1982年   19篇
  1980年   19篇
  1979年   37篇
  1978年   20篇
  1977年   26篇
  1975年   15篇
  1974年   15篇
  1968年   16篇
  1966年   14篇
排序方式: 共有4015条查询结果,搜索用时 15 毫秒
1.
IgG-maleimide peroxidase, Fab'-maleimide peroxidase, polymer and monomer types of Fab'-periodate peroxidase were prepared from an antibody against rat lipoamide dehydrogenase, a component of the pyruvate dehydrogenase complex which is located in mitochondria. They were examined for immunohistochemical staining of the rat kidney. Fab'-maleimide peroxidase was the best for staining mitochondrial protein. IgG-maleimide peroxidase and the monomer type of Fab'-periodate peroxidase had the same intensity of staining. The polymer type of Fab'-periodate peroxidase could not stain the lipoamide dehydrogenase.  相似文献   
2.
3.
4.
We report herein a rare case of a 26 year old woman with pheochromocytoma complicated by paralytic ileus. She presented with remarkable abdominal distension and respiratory difficulty but was effectively treated by surgical removal of the tumor with preoperative and operative management using alpha and beta adrenergic blocking agents. An excessive and persistent catecholamine production from large tumors or massive metastases characterizes this rare complication, and a review of the English and Japanese literature is given following this report.  相似文献   
5.
6.
In 97 neonates receiving total parenteral nutrition in the postoperative period, clinical assessment was made for a newly devised amino acid solution (PF-I-III) from the standpoint of plasma amino acid profile and nutritional effect. These amino acid solutions prepared are characterized by the high concentration of branched-chain amino acids up to 40%, increased arginine and decreased glycine, phenylalanine and methionine as compared with commercially available solutions. In the PF group, each amino acid was kept within the range of standard value. Correlation between plasma amino acid profiles and the dose of each amino acid administered was obtained, from which minimum, standard, and maximum doses for each amino acid was determined. Based on these values, we proposed new formula for neonates which elicits no abnormal plasma amino acid pattern even when amino acids are administered at the dosage level of 1.5-2.5 g/kg/day.  相似文献   
7.
We determined the inhibition-dissociation constant (Ki) of a number of neuroleptics for D1 receptors of normal human brain tissue using [3H]SCH23390 [R-(+)-8-chloro-2,3,4,5-tetrahydro-3-methyl-5-phenyl-1H-3[benzazepine-7- ol]. SCH23390 had the highest affinity with a Ki of 0.76 nM. Among clinically used drugs, propericiazine showed the highest affinity with a Ki of 10 nM. When neuroleptics were classified according to chemical structures, the Ki values were as follows. Phenothiazines ranged from 10 nM to 250 nM. Butyrophenones ranged from 45 nM to 250 nM. Thioxanthenes ranged from 12 nM to 340 nM. Orthopramines were more than 10,000 nM. The Ki values for the binding site of this study were significantly correlated with those reported in studies using animal brain. The possible relationship between D1 receptors and negative symptoms is discussed.  相似文献   
8.
9.
The acute onset of peritoneal signs and shock in a 7year-old boy who had been hit in the epigastrium by a log-seesaw mandated surgical treatment. Enhanced computed tomography (CT) demonstrated complete laceration of the pancreas as well as duodenal injury, and a duodenoduodenostomy with distal pancreaticogastrostomy was subsequently performed. Temporary external drainage of the stomach and distal pancreas led to an uneventful recovery in the early postoperative period. Although the patient's postoperative development was appropriate for his age, the orifice of the distal pancreas spontaneously closed 2.5 years following surgery. We present this report to stress the fact that every effort should be made to preserve the pancreas following abdominal injury in children.  相似文献   
10.
Purine deoxyribonucleoside 3'-phosphates were reacted separately with the four configurational isomers of benzo[c]phenanthrene 3,4-dihydrodiol 1,2-epoxide. Products resulting from the cis and trans opening of the epoxide ring by the exocyclic amino groups of deoxyadenosine and deoxyguanosine 3'-phosphates were separated by high-pressure liquid chromatography and identified by comparison of the observed circular dichroism spectra with the known spectra for the corresponding nucleoside adducts. The 16 structurally identified benzo[c]phenanthrene-purine deoxyribonucleoside 3'-phosphate adducts were then separately postlabeled according to the Randerath method, and the positions of the individual bisphosphates were mapped by thin-layer chromatography. Chromatographic conditions were developed that allowed separation of the four adducts for 3 of the 4 dihydrodiol epoxide isomers.  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