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   1324篇
  免费   116篇
  国内免费   19篇
耳鼻咽喉   13篇
儿科学   35篇
妇产科学   15篇
基础医学   176篇
口腔科学   39篇
临床医学   72篇
内科学   417篇
皮肤病学   127篇
神经病学   86篇
特种医学   25篇
外科学   131篇
综合类   13篇
预防医学   59篇
眼科学   6篇
药学   54篇
肿瘤学   191篇
  2024年   5篇
  2023年   14篇
  2022年   21篇
  2021年   21篇
  2020年   19篇
  2019年   26篇
  2018年   47篇
  2017年   58篇
  2016年   50篇
  2015年   48篇
  2014年   58篇
  2013年   51篇
  2012年   91篇
  2011年   101篇
  2010年   57篇
  2009年   40篇
  2008年   65篇
  2007年   81篇
  2006年   92篇
  2005年   90篇
  2004年   74篇
  2003年   74篇
  2002年   73篇
  2001年   15篇
  2000年   11篇
  1999年   20篇
  1998年   17篇
  1997年   9篇
  1996年   5篇
  1995年   12篇
  1994年   11篇
  1993年   5篇
  1992年   11篇
  1991年   11篇
  1990年   10篇
  1989年   13篇
  1988年   9篇
  1987年   5篇
  1986年   5篇
  1985年   5篇
  1984年   5篇
  1983年   2篇
  1982年   4篇
  1981年   3篇
  1979年   4篇
  1978年   2篇
  1977年   4篇
  1975年   1篇
  1973年   2篇
  1972年   1篇
排序方式: 共有1459条查询结果,搜索用时 15 毫秒
11.
We performed morphological and physiological studies in 43 male patients with alcohol dependence (ALC) who had no other apparent lesions in the upper gastrointestinal tract except atrophic and erosive gastritis. A gastric secretory study in which tetragastrin was used as the stimulant revealed that acid and pepsin secretion was less in ALC patients than in hospital controls (p less than 0.001). Endoscopic biopsy specimens of gastric mucosa from ALC patients revealed that atrophy of the gastric mucosa advanced with age. A strong negative correlation was also found between the secretory capacity of the stomach and the degree of atrophy. Possibly, the interval between recurrent episodes of acute mucosal damage was too short to allow complete healing of mucosal lesions. Failure to regenerate denuded epithelium would result in a decrease in the gastric secretory area. Thus, chronic alcohol abuse seems to be an etiological factor in atrophic gastritis.  相似文献   
12.
13.
A 51-year-old man had a reddish flat granular lesion in the stomach on endoscopic examination. Histology of biopsied specimen confirmed the diagnosis of low-grade B-cell gastric lymphoma of mucosaassociated lymphoid tissue (gastric MALT lymphoma) and simultaneous infection withHelicobacter pylori. He was given antibiotic treatment. Five weeks later, endoscopy and histology of biopsied specimen showed eradication ofH. pylori, and the tumor had regressed. Six months later,H. pylori reemerged, but the tumor had not recurred. After the second antibiotic therapy,H. pylori has been eradicated. The lymphoma has been in remission for 14 months.  相似文献   
14.
Background—It is well established that glutaminesupplemented elemental diets result in less severe intestinal damage inexperimental colitis. However, few studies have examined the mode ofaction of glutamine in reducing intestinal damage.
Aims—To examine the effects of glutaminesupplemented elemental diets on the potent inflammatory cytokinesinterleukin 8 (IL-8) and tumour necrosis factor α (TNF-α) intrinitrobenzene sulphonic acid (TNBS) induced colitis which presentswith both acute and chronic features of ulcerative colitis.
Methods—Sprague-Dawley rats were randomised intothree dietary groups and fed 20% casein (controls), or 20% caseinsupplemented with either 2% glutamine (2% Gln) or 4% glutamine (4%Gln). After two weeks they received intracolonic TNBS to inducecolitis.
Results—Both Gln groups of rats gained more weight thanthe control group (p<0.05) which had progressive weight loss. Colon weight, macroscopic, and microscopic damage scores for the Gln groupswere lower than in the control group (p<0.05). IL-8 and TNF-αconcentrations in inflamed colonic tissues were lower in the Gln groupsthan in the control group (p<0.05), and correlated well with diseaseseverity. Bacterial translocation was lower both in incidence (p<0.05)and in the number of colony forming units (p<0.05) for the Gln groups,than in the control group. With respect to all indices studied, the 4%Gln group performed better than did the 2% Gln group.
Conclusion—Prophylactic glutamine supplementationmodulates the inflammatory activities of IL-8 and TNF-α in TNBSinduced colitis.

Keywords:glutamine; trinitrobenzene sulphonic acid; inflammatory bowel disease; rats; interleukin 8; tumour necrosis factorα

  相似文献   
15.
We place on record 2 infants with the DiGeorge syndrome and anomalous origin of the left pulmonary artery from the ascending aorta. We postulate that: (1) embryogenesis of anomalous origin of the left pulmonary artery from the ascending aorta might be due to the persistent fifth aortic arch connecting both arterial systems; (2) an anomalous pulmonary artery arising from the ascending aorta is part of the aortic arch abnormality accompanied by normal conotruncal septation; and (3) in the DiGeorge syndrome, cardiac anomalies that originate from the conotruncus or aortic arch, or both, may have the same embryologic mechanisms.  相似文献   
16.
BACKGROUND: To evaluate the imaging possibility of a newly designed electronic radial scanning echoendoscope (ER-ES). METHODS: In the in vivo study of swine, we obtained B-mode endoscopic ultrasonography (EUS) images of the gastric and gallbladder (GB) walls and checked the ability to detect Doppler signals using ER-ES and electronic linear array echoendoscope (EL-ES). Furthermore, in the ex vivo study of swine, B-mode EUS images of fixed gastric and GB wall specimens were obtained using ER-ES, EL-ES and mechanical radial scanning echoendoscope (MR-ES). In the study of resected human specimens, we obtained B-mode EUS images of five resected GB specimens (three normal GB, one cholecystitis and one cancerous) using the three types of echoendoscope. RESULTS: In the in vivo study of swine, ER-ES and EL-ES depicted the gastric walls as five-layered, and the GB walls as single-layered structures. The ability to detect Doppler signals was equal between ER-ES and EL-ES. In the ex vivo study of swine, ER-ES, MR-ES and EL-ES equally delineated the gastric walls as five-layered and GB walls as three-layered structures. In the study of resected human specimens, results demonstrated the normal GB walls as three-layered, the cholecystitis as a combination of outer high-echoic and inner low-echoic layers, and the cancer as a protruded tumor. CONCLUSIONS: We conclude that ER-ES has faculties for making B-mode images as well as EL-ES and MR-ES. In addition, in the in vivo study, ER-ES can analyze blood flow information as well as EL-ES.  相似文献   
17.
18.
19.
To clarify the role of mucosal blood flow in the pathogenesis of ulcer formation, the authors investigated dulcerozine-induced duodenal ulcers in rats. Administration of dulcerozine, 500 mg/kg by intragastric route or 250 mg/kg given intraperitoneally, induced acute ulcers in the duodenum, but not the stomach, in all rats. Using the pyloric ligation method, it was determined that although dulcerozine significantly increased gastric acid secretion, no duodenal ulcers were observed in these animals. The administration of 1 ml of 0.1 N HC1 every hour for 6 hours did not induce duodenal ulceration. The mucus glycoprotein content of the corpus, antrum and proximal duodenum did not differ following dulcerozine administration. Duodenal mucosal blood flow, which was measured by an electrolytically generated hydrogen gas clearance technique, decreased significantly following dulcerozine administration even in pylorus-ligated rats. In contrast, there was an increase in the gastric mucosal blood flow following administration of the drug. Therefore, not only an increase in gastric acid secretion but also a decrease in duodenal mucosal blood flow are suggested to be responsible for dulcerozine-induced duodenal ulceration.  相似文献   
20.
A 75-year-old woman was diagnosed with esophageal cancer with difficulty in swallowing. She had a past history of rheumatoid arthritis, scleroderma, interstitial pneumonia, angina pectoris (with coronary artery bypass surgery) and arrhythmia (with pacemaker implantation). She refused surgery, and chemotherapy and radiotherapy were not performed because of the high risk accompanied with multiple comorbidities. She received proton therapy at another hospital and the primary lesion shrank. Bone metastasis in the thoracic vertebrae was diagnosed 10 months after diagnosis of esophageal cancer. Non-steroidal anti-inflammatory drugs and zoledronic acid were administered for back pain. Oxycodone was also administered but discontinued due to nausea. After strontium-89 (89Sr) chloride administration, her back pain was relieved. 89Sr was administered five times every 3 months, and the pain did not worsen until her death due to pneumonia 2 years after diagnosis of esophageal cancer. 89Sr was effective for pain from bone metastasis of esophageal cancer, and its repeated administration was safe.  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