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   25874篇
  免费   1360篇
  国内免费   99篇
耳鼻咽喉   175篇
儿科学   444篇
妇产科学   406篇
基础医学   3112篇
口腔科学   792篇
临床医学   1821篇
内科学   6223篇
皮肤病学   554篇
神经病学   2269篇
特种医学   1106篇
外科学   4143篇
综合类   104篇
预防医学   708篇
眼科学   517篇
药学   1951篇
  1篇
中国医学   57篇
肿瘤学   2950篇
  2023年   136篇
  2022年   226篇
  2021年   504篇
  2020年   294篇
  2019年   398篇
  2018年   452篇
  2017年   381篇
  2016年   489篇
  2015年   491篇
  2014年   668篇
  2013年   785篇
  2012年   1213篇
  2011年   1386篇
  2010年   702篇
  2009年   641篇
  2008年   1118篇
  2007年   1163篇
  2006年   1137篇
  2005年   1132篇
  2004年   1063篇
  2003年   1069篇
  2002年   1077篇
  2001年   934篇
  2000年   952篇
  1999年   934篇
  1998年   319篇
  1997年   253篇
  1996年   236篇
  1995年   199篇
  1994年   178篇
  1993年   161篇
  1992年   661篇
  1991年   575篇
  1990年   603篇
  1989年   588篇
  1988年   498篇
  1987年   461篇
  1986年   454篇
  1985年   405篇
  1984年   281篇
  1983年   239篇
  1980年   93篇
  1979年   240篇
  1978年   143篇
  1977年   131篇
  1975年   101篇
  1974年   96篇
  1972年   105篇
  1971年   107篇
  1969年   101篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
We report a case of a diaphragmatic hernia after a heart transplant operation. A 43-year-old woman, who underwent orthotropic heart transplantation for hypertrophic cadiomyopathy two year earlier, presented with vomiting and epigastric pain. A computed tomography scan showed that the stomach and transverse colon were dislocated in the left thoracic cavity. We diagnosed left diaphragmatic hernia incarceration and performed laparoscopic repair of the diaphragmatic hernia. A 12 × 8 cm diaphragmatic defect was found intraoperatively on the ventrolateral aspect of the left diaphragm, and the stomach with volvulus had herniated into the thorax through the defect. The hernia was considered to be iatrogenic. The diaphragmatic defect was large, and the diaphragm was thinning. We closed the defect by mesh repair. Laparoscopic mesh repair of the diaphragmatic hernia could be performed safely and with minimal invasiveness.  相似文献   
2.

Background

There were few studies assessed the postoperative sarcopenia in patients with cancers. The objective of present study was to assess whether postoperative development of sarcopenia could predict a poor prognosis in patients with adenocarcinoma of esophagogastric junction, (AEG) and upper gastric cancer (UGC).

Methods

Patients with AEG and UGC who were judged as non-sarcopenic before surgery were reassessed the presence of postoperative development of sarcopenia 6 months after surgery. Patients were divided into the development group or non-development group, and clinicopathological factors and prognosis between these two groups were analyzed.

Results

The 5-year overall survival rates were significantly poorer in the development group than non-development group (68.0% vs. 92.6%, P?=?0.0118). Multivariate analyses showed that postoperative development of sarcopenia was an independent prognostic factor for poor overall survival (P?=?0.0237).

Conclusions

Postoperative development of sarcopenia was associated with a poor prognosis in patients with AEG and UGC.  相似文献   
3.
Idiopathic myointimal hyperplasia of mesenteric veins (IMHMV) is a rare and poorly understood ischemic colitis that occurs in the rectosigmoid colon of predominantly young, previously healthy, male patients. A 76‐year‐old Japanese man presented to our hospital with a 1‐year history of worsening diarrhea, lower abdominal pain, and weight loss (−6 kg). Laboratory evaluation revealed white blood cell count of 13 200/μL, C‐reactive protein level of 2.0 mg/dL (normal range, 0.0–0.3), and negative results for stool culture (including Clostridium difficile). Colonoscopy showed circumferential and edematous narrowing of the sigmoid colon with deep longitude ulceration. Biopsy was done and examination of the specimen demonstrated no specific ischemia. The patient was treated with bowel rest, antibiotics, and i.v. fluids; however, his symptoms worsened. Finally, sigmoidectomy was carried out. Histological examination demonstrated significant myointimal hyperplasia of mesenteric veins leading to thickening and stenosis of the venous lumen. Therefore, the final diagnosis was IMHMV. Three months following sigmoidectomy, he was asymptomatic.  相似文献   
4.
5.
6.
7.
8.
EDITORIAL COMMENT: We accepted this case for publication to remind readers that although uterine rupture during labour in a primigravida is extremely uncommon it does occur, or at any rate nulliparas can develop abdominal pain and shock in labour with a haemoperitoneum resulting from a tear in a vein in the lower posterior uterine wall. When one sees the hugely dilated uterine and ovarian venous plexuses at Caesarean section it is easy to believe that bleeding from such a vessel during labour could be prodigious. This case suggests that a dilated vein with blood flow derangements may be the cause. Nonetheless, as the authors warn us, the necessary response is not a precise diagnosis, but rapid laparotomy. See also Editorial Comment to Chin MMS, Harvey JA, Duffy BL. Uterine rupture during labour in a primigravida. Aust NZ J Obstet Gynaecol 1996; 36: 210.  相似文献   
9.
10.
Experiments were performed on spinalized rats, transected at the Cl level. The intravenous administration of TRH and its analog YM-14673 (N alpha-[(S)-4-oxo-2-azetidinyl) carbonyl]-L-histidyl-L-prolinamide dehydrate) produced marked increases in the amplitude of mono- and polysynaptic reflex potentials and those of the withdrawal flexor reflexes. The effects of YM-14673 were stronger and longer-lasting than those of TRH. The stimulant action of TRH and YM-14673 on the flexor reflexes was not antagonized by prazosin, chlorpromazine, haloperidol or cyproheptadine, suggesting no involvement of the release of catecholamines or serotonin in the stimulant effects of TRH and its analog. Therefore, YM-14673 may be beneficial for the treatment of several spinal motor neuron diseases.  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