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   6441篇
  免费   357篇
  国内免费   43篇
耳鼻咽喉   53篇
儿科学   169篇
妇产科学   56篇
基础医学   687篇
口腔科学   105篇
临床医学   371篇
内科学   1885篇
皮肤病学   75篇
神经病学   391篇
特种医学   135篇
外科学   1262篇
综合类   35篇
一般理论   1篇
预防医学   176篇
眼科学   229篇
药学   521篇
中国医学   12篇
肿瘤学   678篇
  2023年   59篇
  2022年   89篇
  2021年   173篇
  2020年   80篇
  2019年   123篇
  2018年   154篇
  2017年   132篇
  2016年   172篇
  2015年   172篇
  2014年   212篇
  2013年   237篇
  2012年   381篇
  2011年   380篇
  2010年   229篇
  2009年   205篇
  2008年   320篇
  2007年   325篇
  2006年   327篇
  2005年   327篇
  2004年   324篇
  2003年   253篇
  2002年   264篇
  2001年   175篇
  2000年   187篇
  1999年   163篇
  1998年   84篇
  1997年   51篇
  1996年   42篇
  1995年   57篇
  1994年   57篇
  1993年   43篇
  1992年   103篇
  1991年   76篇
  1990年   78篇
  1989年   88篇
  1988年   89篇
  1987年   76篇
  1986年   66篇
  1985年   74篇
  1984年   48篇
  1983年   39篇
  1982年   19篇
  1980年   23篇
  1979年   25篇
  1978年   17篇
  1974年   17篇
  1973年   16篇
  1972年   20篇
  1969年   27篇
  1968年   26篇
排序方式: 共有6841条查询结果,搜索用时 15 毫秒
1.
Mutations in the gene encoding 11beta-hydroxysteroid dehydrogenase type 2, HSD11B2, cause a rare monogenic juvenile hypertensive syndrome called apparent mineralocorticoid excess (AME). In AME, defective HSD11B2 enzyme activity results in overstimulation of the mineralocorticoid receptor (MR) by cortisol, causing sodium retention, hypokalemia, and salt-dependent hypertension. Here, we have studied whether genetic variations in HDS11B2 are implicated in essential hypertension in Japanese hypertensives and the general population. By sequencing the entire coding region and the promoter region of HDS11B2 in 953 Japanese hypertensives, we identified five missense mutations in 11 patients (L14F, n = 5; R74H, n = 1; R147H, n = 3; T156I, n = 1; R335H, n = 1) and one novel frameshift mutation (4884Gdel, n = 1) in a heterozygous state, in addition to 19 genetic variations. All genetic variations identified were rare, with minor allele frequencies less than 0.005. Four of 12 patients with the missense/frameshift mutations showed renal failure. Four missense mutations, L14F, R74H, R147H, and R335H, were successfully genotyped in the general population, with a sample size of 3,655 individuals (2,175 normotensives and 1,480 hypertensives). Mutations L14F, R74H, R147H, and R335H were identified in hypertensives (n = 6, 8, 3, and 0, respectively) and normotensives (n = 8, 12, 5, and 0, respectively) with a similar frequency, suggesting that these missense mutations may not strongly affect the etiology of essential hypertension. Since the allele frequency of all of the genetic variations identified in this study was rare, an association study was not conducted. Taken together, our results indicate that missense mutations in HSD11B2 do not substantially contribute to essential hypertension in Japanese.  相似文献   
2.
A 23-year-old man was admitted for treatment of acute exacerbation of ileitis and perianal abscess caused by Crohn's disease. After incision and drainage of the abscess, coupled with antibiotic therapy, 6-mercaptopurine (6-MP) was commenced. His white blood cell (WBC) count on day 12 after initiation of 6-MP was not decreased. However, on day 24 he was re-admitted because of severe myelosuppression (WBC: 300/microl), which was complicated by the recurrence of the perianal abscess. Myelosuppression was prolonged and required the administration of granulocyte colony stimulating factor (G-CSF). G-CSF was continued for 17 days to achieve recovery of his WBC count to a normal level.  相似文献   
3.
A 44-year-old women developed marked myopathy one year earlier, when she was treated with intravenous prednisolone for acute severe exacerbation of ulcerative colitis. When she was admitted to our hospital for another severe exacerbation, intravenous cyclosporine A was administered as monotherapy because she could not tolerate corticosteroid. The treatment was successful and she obtained complete remission. Cyclosporine A monotherapy is considered to be a valuable alternative to proctocolectomy for severe ulcerative colitis patients who cannot tolerate corticosteroid.  相似文献   
4.
The requirement for endoscopic access to a stricture is a major limitation of the endoscopic dilatation for the treatment of strictures in the gastrointestinal tract. We have developed the double‐balloon enteroscopy method that enables visualization of the entire small bowel. In addition, double‐balloon enteroscopy has a potential for the interventional therapy including dilatation of strictures. We present here a case of jejunal strictures in a 47‐year‐old woman with Crohn's disease successfully treated with a balloon catheter in combination with double‐balloon enteroscopy. Balloon dilation with double‐balloon enteroscopy is a promising method for the treatment of small bowel strictures in Crohn's disease.  相似文献   
5.
6.
Gross hemorrhage is the most serious complication of anticoagulant therapy. We report the discovery and treatment of a large pseudoaneurysm of the superior gluteal artery in one patient who had been receiving oral anticoagulant therapy. We diagnosed the pseudoaneurysm by contrast-enhanced computed tomography, and embolized the artery with stainless steel coils. The exact cause of the pseudoaneurysm remains unclear, however, minor trauma appears most likely.  相似文献   
7.
8.
An aggressive pancreatectomy was performed on a 53 year old Japanese man with advanced cancer of the pancreas. The tumor originated from the body of the pancreas and invaded the stomach, duodenum, left kidney, transverse colon and common hepatic artery. An unexpected cancer was also found in the head of the pancreas during the operation. Therefore, total pancreatectomy, total gastrectomy, left adrenonephrectomy, resection of the left transverse colon and dissection of the regional lymph nodes were performed. Resection of the common hepatic artery was also performed, followed by an end-to-end anastomosis between the common hepatic artery and celiac trunk. The postoperative course was uneventful and the patient was doing well until nine months after the operation when multiple metastatic lesions were noted in the liver. He died 391 days after the operation from hepatic failure.  相似文献   
9.
Yamamoto and colleagues have developed a novel insertion method of the endoscope, the ‘double balloon method’ for enteroscopy and, recently, a specialized system for the ‘double balloon method’ has been commercialized by Fujinon. The double balloon endoscopy enables visualization of the entire small bowel and also allows for interventional therapy in the small intestine. This method could be used either from the oral or anal approach. Observation of an affected area with controlled movement of the endoscope enables interventions, including biopsies, hemostasis, balloon dilatation, stent placement, polypectomy, and endoscopic mucosal resection. The procedure is safe and useful, and it provides high diagnostic yields and therapeutic capabilities.  相似文献   
10.
We examined a gene polymorphism of a novel Z-disc-related protein, myospryn (cardiomyopathy-associated 5). We focused on one haplotype block associated with a tag single nucleotide polymorphism (SNP) that covered 16 of 27 coding SNPs with linkage disequilibrium (minor allele frequency 0.413). Screening a myospryn polymorphism (K2906N) in a general health check-up of a rural Japanese population revealed an association with cardiac diseases (p=0.0082). In further analysis of the interaction between K2906N and cardiac function in patients, K2906N was associated with the anteroseptal wall thickness of the left ventricle in a recessive model (p=0.0324) and with the ratio of the peak velocity of the early diastolic filling wave to the peak velocity of atrial filling (A/E) (p=0.0278). In an association study based on left ventricular wall thickness, we found a significant difference in the K2906N genotype between controls and patients with cardiac hypertrophy. These results suggest that the K2906N polymorphism could be clinically associated with left ventricular hypertrophy and diastolic dysfunction independent of known parameters. Although the precise mechanism underlying this association remains to be elucidated, treatment with angiotensin II induced an increase in heart myospryn mRNA level in vitro and in vivo. Our results suggest that the polymorphism of myospryn is associated with left ventricular hypertrophy, and an association between a Z-disc protein and cardiac adaptation in response to pressure overload.  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