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   5617篇
  免费   291篇
  国内免费   24篇
耳鼻咽喉   42篇
儿科学   331篇
妇产科学   84篇
基础医学   670篇
口腔科学   87篇
临床医学   410篇
内科学   1227篇
皮肤病学   64篇
神经病学   436篇
特种医学   116篇
外科学   765篇
综合类   154篇
一般理论   1篇
预防医学   309篇
眼科学   201篇
药学   612篇
中国医学   78篇
肿瘤学   345篇
  2023年   49篇
  2022年   94篇
  2021年   212篇
  2020年   91篇
  2019年   135篇
  2018年   187篇
  2017年   128篇
  2016年   140篇
  2015年   166篇
  2014年   239篇
  2013年   324篇
  2012年   422篇
  2011年   450篇
  2010年   251篇
  2009年   211篇
  2008年   318篇
  2007年   305篇
  2006年   251篇
  2005年   253篇
  2004年   195篇
  2003年   177篇
  2002年   183篇
  2001年   83篇
  2000年   80篇
  1999年   83篇
  1998年   57篇
  1997年   36篇
  1996年   39篇
  1995年   29篇
  1993年   27篇
  1992年   41篇
  1991年   57篇
  1990年   56篇
  1989年   42篇
  1988年   35篇
  1987年   43篇
  1986年   26篇
  1985年   49篇
  1984年   31篇
  1983年   27篇
  1982年   24篇
  1981年   17篇
  1980年   16篇
  1979年   20篇
  1978年   23篇
  1977年   19篇
  1974年   15篇
  1973年   23篇
  1971年   17篇
  1969年   18篇
排序方式: 共有5932条查询结果,搜索用时 15 毫秒
1.
Intussusception is a very rare cause of intestinal obstruction in neonates. It is of extremely rare occurrence among premature neonates. We present a case of 11-day-old premature neonate who presented with abdominal distension, intolerance to feeds, vomiting, significant bilious aspirate and bleeding per rectum. The initial diagnosis of necrotizing enterocolitis (NEC) led to a delay in the diagnosis. On exploratory laparotomy, it turned out to be a case of ileo-colic intussusception with Meckel''s diverticulum as a lead point. This site of intussusception (ileo-colic) and presence of a lead point among premature neonate is of exceedingly rare occurrence and very few such cases have been reported.In this article, the published work about clinical features and management on intussusceptions in premature neonates has been reviewed. The authors intend to highlight the difficulty in distinguishing the NEC and intussusception. Subtle clinical and radiological features which can help in differentiating the two conditions have been emphasized. This can avoid the delay in diagnosis and management which can prove critical. High index of suspicion with timely intervention is the key for optimizing outcome. A diagnosis of intussusception should always be considered in any preterm infant with suspected NEC.  相似文献   
2.
3.
Ziprasidone (Geodone), a novel atypical antipsychotic agent, is recently approved for the treatment of schizophrenia. It undergoes extensive metabolism in preclinical species and humans after oral administration, and only a very small amount of administered dose is excreted as unchanged drug. In vitro studies using human liver microsomes have shown that the oxidative metabolism of ziprasidone is mediated primarily by CYP3A4. However, coadministration of ziprasidone with ketoconazole, a CYP3A4 inhibitor, showed only a modest increase in its exposure. Therefore, in vitro metabolism of ziprasidone was investigated in hepatic cytosolic fractions to further understand its clearance mechanisms in preclinical species and humans. The major metabolite from incubation of ziprasidone in cytosolic fractions of rat, dog, and human was characterized by liquid chromatography-tandem mass spectrometry and found to be the product of reductive cleavage. Derivatization and hydrogen/deuterium exchange were used to deduce that the addition of two hydrogen atoms had occurred at the benzisothiazole moiety. Further studies to determine the enzyme involved in the formation of this metabolite are currently in progress. The identification of this novel metabolite in cytosol has clarified the clearance mechanism of ziprasidone in humans and preclinical species.  相似文献   
4.
5.
6.
BACKGROUND: Intrahepatic stones, though common in East Asia, are uncommon in India. There is paucity of data from India regarding the treatment and long-term outcome of patients with intrahepatic stones. METHODS: We retrospectively analyzed medical records of 35 patients with intrahepatic stones who had been treated surgically. Endoscopic biliary drainage had been used in patients who presented with acute cholangitis. Intraoperative stone clearance was confirmed by choledochoscopy and intraoperative cholangiography. Outcome of surgery, frequency and subsequent management of recurrent intrahepatic stones, and factors associated with stone recurrence and cholangitis were analyzed. RESULTS: Twenty-one (60%) patients had bilobar disease. Eight patients underwent hepatectomy and 16 hepatico-jejunostomy with access loop; 12 of these were jejuno-duodenal anastomoses. Postoperative morbidity was observed in 10 patients (29%). Recurrence of stones occurred in 12 patients (34%) and cholangitis in 9 patients (26%). Presence of bilobar disease and associated biliary strictures were associated with recurrent cholangitis (p< 0.05). Two patients (6%) required re-operation for recurrent cholangitis. Complete removal of recurrent stones using conventional endoscope was possible through jejuno-duodenostomy in all 5 cases who had this type of access loop construction. CONCLUSION: Surgical treatment for intrahepatic stones depends on the site of involvement. Construction of a jejuno-duodenal access loop in patients with bilobar disease and intrahepatic strictures is helpful in facilitating postoperative stone clearance. A multidisciplinary approach is beneficial especially when the disease is bilobar and recurrent in type.  相似文献   
7.
8.
Supragaleal placement of tissue expander for management of alopecia of scalp excludes tough galeal layer so that easier and faster expansion of scalp may be achieved.  相似文献   
9.
This communication highlights scleral dellen as an unusual complication of strabismus surgery in a 55-year-old hypertensive male. The clinical significance, differential diagnosis and management of this condition has been discussed.  相似文献   
10.
Combined Tc-99m MDP skeletal imaging and Tc-99m(V) DMSA whole body scans to detect metastases were performed during the follow-up of 30 patients who underwent surgery for breast carcinoma. Eight patients had normal Tc-99m MDP and Tc-99m(V) DMSA scans and were declared free of metastatic disease, further confirmed by no change in symptomatology over a 1-year follow-up period. Twenty-two patients had positive Tc-99m MDP scans with varied skeletal involvement. Tc-99m(V) DMSA scans showed matched areas of increased radiotracer concentration in bony metastases in 20 of these patients. Tc-99m(V) DMSA concentration was not seen in traumatic vertebral collapse or in coexistent osteoarthritic disease in vertebral metastatic involvement. Interestingly, Tc-99m(V) DMSA showed increased concentration in brain and liver metastases. Pentavalent Tc-99m(V) DMSA appears useful for detecting skeletal and soft-tissue metastases in breast carcinoma, and can improve the specificity of Tc-99m MDP bone scans in screening for bone metastases.  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