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   12622篇
  免费   1130篇
  国内免费   16篇
耳鼻咽喉   152篇
儿科学   369篇
妇产科学   234篇
基础医学   1652篇
口腔科学   448篇
临床医学   1146篇
内科学   3139篇
皮肤病学   184篇
神经病学   1287篇
特种医学   272篇
外国民族医学   3篇
外科学   1723篇
综合类   264篇
一般理论   14篇
预防医学   1290篇
眼科学   286篇
药学   712篇
中国医学   10篇
肿瘤学   583篇
  2021年   190篇
  2020年   103篇
  2019年   151篇
  2018年   215篇
  2017年   141篇
  2016年   136篇
  2015年   191篇
  2014年   258篇
  2013年   500篇
  2012年   589篇
  2011年   649篇
  2010年   369篇
  2009年   356篇
  2008年   618篇
  2007年   718篇
  2006年   679篇
  2005年   674篇
  2004年   685篇
  2003年   640篇
  2002年   639篇
  2001年   148篇
  2000年   150篇
  1999年   132篇
  1998年   135篇
  1997年   138篇
  1996年   114篇
  1995年   107篇
  1994年   113篇
  1993年   108篇
  1992年   105篇
  1991年   131篇
  1990年   121篇
  1989年   125篇
  1988年   113篇
  1987年   87篇
  1986年   108篇
  1985年   118篇
  1984年   154篇
  1983年   152篇
  1982年   173篇
  1981年   155篇
  1980年   169篇
  1979年   120篇
  1978年   135篇
  1977年   120篇
  1976年   115篇
  1975年   99篇
  1974年   78篇
  1973年   98篇
  1972年   85篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
71.
Comparison of the use of nalbuphine and fentanyl during third molar surgery   总被引:1,自引:0,他引:1  
In a double-blind, randomized plan of drug administration, nalbuphine, fentanyl, and a placebo were compared for efficacy in sedation and analgesia during third molar removal. Fifty-eight patients participated in this study. Using accepted intravenous sedation and surgical techniques, fentanyl and nalbuphine were found to be better than placebo for anxiety and pain control in third molar surgery. Fentanyl had a longer duration of pain relief postoperatively than did nalbuphine. The study confirmed the need for a narcotic supplement to sedation techniques for third molar surgery.  相似文献   
72.
73.
Gallbladder dyskinesia in chronic acalculous cholecystitis   总被引:4,自引:0,他引:4  
To test the hypothesis that there is an early stage of cholesterol gallstone formation in man characterized by symptoms of chronic cholecystitis, poor gallbladder emptying, and biliary cholesterol crystals, we studied cholecystokinin-stimulated gallbladder emptying by DISIDA scintigraphy and examined bile for cholesterol crystals in symptomatic patients with normal oral cholecystography and gallbladder sonography. Of 36 patients studied, 16 had biliary cholesterol crystals; their mean 30-min gallbladder ejection fraction was 25.9±14.8%. Among the 20 patients without crystals, the mean ejection fraction was 60.3±23.3%. Fifteen patients, 11 with crystals and four without, had cholecystectomy because of persistent symptoms. All with crystals preoperatively and three without had chronic cholecystitis histologically. One patient without crystals had normal histology. We conclude that poor gallbladder contractility, well-established as an etiologic factor in animal models of cholesterol cholelithiasis, is now linked to acalculous cholecystitis, an early stage of human cholesterol cholelithiasis.  相似文献   
74.
Hematological Complications of Alcoholism   总被引:4,自引:0,他引:4  
Numerous clinical observations support the notion that ethanol has multiple pathologic effects on hematopoietic tissue. The effects of alcohol on blood are diverse. The long-term ingestion of large quantities of ethanol has been shown to alter a substantial number of physiologic and biochemical variables. Abnormalities involving leukocytes, platelets, and erythrocytes may occur singly or in various combinations. Due to the frequent concomitant presence of alcohol-related hepatic disease, nutritional deficiencies, infection, and other chronic diseases, it is often difficult to distinguish the specific hematologic toxicities of alcohol ingestion from the hematologic toxicities of associated morbid conditions. Depressed hematopoietic cell formation (Table 2), increased destruction, and alterations in morphology and function of hematopoietic cells have been described.  相似文献   
75.
76.
77.
Summary: Tumors and cortical dysplasia are associated with epilepsy, but few studies have examined the coexistence of neoplasia and dysplasia in these patients. We studied 13 patients (age 4–29 years) with recurrent seizures of 1 month to 21-year' duration (median 72 months). Ten patients were aged <21 years. Imaging studies localized the lesion to the temporal lobe (10 patients), parietal lobe (2 patients), and frontal lobe (1 patient). Tumors included ganglioglioma (8 patients), dysembryoplastic neuroepithelial tumor (DNT) (3 patients), and low-grade as- trocytoma (2 patients). Cortical dysplasia, including atypical aggregates of neurons (6 patients), multifocal loss of the cortical laminar architecture (7 patients), and neurons in the molecular layer of the cortex (3 patients) were observed near but separate from the tumor. Coexistence of certain tumors with cortical dysplasia, most frequently observed in the pediatric population, suggests a hamar-tomatous/dysplastic nature of the neoplasms.  相似文献   
78.
Dolasetron is a 5-hydroxytryptamine antagonist active at type III receptors; it is presently undergoing clinical evaluation for the reduction/prevention of cancer chemotherapyinduced nausea and vomiting. A previous study demonstrated that following intravenous administration to healthy male subjects, dolasetron disappeared extremely rapidly from plasma, and less than 1 per cent of the dose appeared in the urine. A major plasma metabolite, reduced dolasetron, peaked rapidly in the plasma. In this study, dolasetron was administered orally to healthy male subjects at doses ranging from 50 to 400 mg (mesylate monohydrate). Plasma concentrations of dolasetron were low and sporadic, and there was little excreted in urine; this prevented dolasetron pharmacokinetic analysis. Reduced metabolite concentrations peaked rapidly, with a median value of 1.00 h. The median terminal disposition half-life was 7.80 h. Median values for fraction of dose excreted in urine and renal clearance were 22.2 per cent and 2.56 ml min?1 kg?1. Whereas areas under the plasma concentration—time curves were proportional to dose, renal clearance increased with dose (p < 0.05). However, given dose proportionality to AUC, this is probably of little therapeutic consequence. Since reduced dolasetron has significant anti-emetic activity in the ferret model, it appears that this metabolite may play a significant role in pharmacodynamic activity.  相似文献   
79.
A patient is reported in whom pretreatment with intravenous lidocaine resulted in failure to elicit a seizure even at stimulus intensity markedly greater than that used successfully at prior and subsequent treatments. Together with one other report, this experience suggests that lidocaine may prevent a seizure by raising the seizure threshold. An alternative explanation is proposed for the classic findings of Ottosson that lidocaine-modified seizures are reduced in therapeutic efficacy.  相似文献   
80.
This paper explores a number of the dimensions of the process of afterwork: the psychological work that former patients engage in after treatment has terminated. Ten former patients, who had worked with 10 different therapists, were interviewed utilizing a semi-structured interview protocol, and their experiences form the basis for the findings and observations that are described. It was found that subjects remembered little by way of lessons or insights; rather, what remained with them were changes of perspective, the internalization of the process of the treatment, and the experience of their therapists' human qualities. In addition, it was found that most subjects had had some form of contact with their therapists post-termination. The implications of these findings are discussed.  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