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   8472篇
  免费   648篇
  国内免费   73篇
耳鼻咽喉   70篇
儿科学   208篇
妇产科学   61篇
基础医学   979篇
口腔科学   187篇
临床医学   592篇
内科学   2486篇
皮肤病学   379篇
神经病学   441篇
特种医学   392篇
外科学   1492篇
综合类   34篇
一般理论   1篇
预防医学   207篇
眼科学   89篇
药学   454篇
中国医学   9篇
肿瘤学   1112篇
  2024年   9篇
  2023年   145篇
  2022年   292篇
  2021年   457篇
  2020年   220篇
  2019年   296篇
  2018年   370篇
  2017年   333篇
  2016年   354篇
  2015年   336篇
  2014年   430篇
  2013年   446篇
  2012年   757篇
  2011年   763篇
  2010年   393篇
  2009年   316篇
  2008年   516篇
  2007年   578篇
  2006年   499篇
  2005年   463篇
  2004年   376篇
  2003年   297篇
  2002年   239篇
  2001年   33篇
  2000年   26篇
  1999年   29篇
  1998年   31篇
  1997年   27篇
  1996年   19篇
  1995年   16篇
  1994年   14篇
  1993年   17篇
  1992年   16篇
  1991年   13篇
  1990年   12篇
  1989年   11篇
  1988年   8篇
  1987年   4篇
  1986年   9篇
  1985年   5篇
  1984年   5篇
  1983年   3篇
  1981年   1篇
  1980年   1篇
  1979年   1篇
  1978年   1篇
  1977年   2篇
  1974年   1篇
  1973年   3篇
排序方式: 共有9193条查询结果,搜索用时 15 毫秒
991.
We describe a case of cardiac masses (high- and iso-echoic mass) which were detected by echocardiography in a 57-year-old man with cerebral infarction. Because he refused both biopsy and surgery, the patient was treated with an anticoagulant and antibiotic in our outpatient clinic. During 3-year follow-up, the iso-echoic mass disappeared and the high-echoic mass did not change. Thus, we considered the iso-echoic mass a thrombus and the high-echoic mass a benign tumor. Cardiac computed tomography revealed that the high-echoic mass had extensive calcifications like phleboliths, and magnetic resonance imaging pattern coincided with that of hemangiomas. We conclude that the benign tumor/high-echoic mass might be a vascular malformation.  相似文献   
992.
993.
Aims/Introduction: Gastric inhibitory polypeptide (GIP) and glucagon‐like peptide‐1 (GLP‐1) are the major incretins; their secretion after various nutrient loads are well‐evaluated in Caucasians. However, little is known of the relationship between incretin secretion and differing nutritional loading in Japanese subjects. In the present study, we evaluated GIP and GLP‐1 secretion in Japanese subjects with normal glucose tolerance (NGT) after glucose loading (75 g glucose and 17 g glucose) and meal ingestion. Materials and Methods: A total of 10 Japanese NGT subjects participated in 75 g oral glucose tolerance test (OGTT), 17 g OGTT and meal tolerance test (MTT). Plasma glucose (PG), serum insulin (IRI), serum C‐peptide (CPR), plasma total GIP, and plasma total GLP‐1 levels during OGTT and MTT were determined. Results: Area under the curve (AUC)‐GIP was increased in proportion to the amount of glucose, and was highest in MTT, showing that GIP secretion is also stimulated by nutrients other than glucose, such as lipid. In contrast, although the larger glucose load tended to induce a larger GLP‐1 release, AUC‐GLP‐1 was not significantly different among the three loading tests (75 g OGTT, 17 g OGTT, MTT) irrespective of the kind or amount of nutrition load. Conclusions: Our results suggest that nutritional composition might have a greater effect on GIP secretion than that on GLP‐1 secretion in Japanese NGT subjects . (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2011.00143.x, 2012)  相似文献   
994.
Aims/Introduction: The effectiveness of incretin‐based therapies in Asian type 2 diabetes requires investigation of the secretion and metabolism of glucose‐dependent insulinotropic polypepide (GIP) and glucagon‐like peptide 1 (GLP‐1). Plasma extractions have been suggested to reduce variability in intact GLP‐1 levels among individuals by removing interference that affects immunoassays, although no direct demonstration of this method has been reported. We have evaluated the effects of ethanol and solid‐phase extractions on incretin immunoassays. We determined incretin levels during meal tolerance tests in Japanese patients with type 2 diabetes and characterized predictors for incretin secretion. Materials and Methods: Japanese patients with type 2 diabetes (23 anti‐diabetic drug‐naïve and 18 treated with sulfonylurea [SU] alone) were subjected to meal tolerance tests, and incretin levels were determined by immunoassays with or without extraction. Results: Intact GLP‐1 levels determined by an intact GLP‐1 immunoassay with ethanol and solid‐phase extractions were lower than those determined without extraction. Intact GLP‐1 levels determined by the extractions were highly correlated with each other, much more so than the levels with and without extraction. Total GLP‐1 was unaffected by extractions, showing that extractions remove interference only in the case of intact GLP‐1. Incretin secretion after meal ingestion was similar between drug‐naïve and SU‐treated patients. Fasting and postprandial GLP‐1 levels were correlated positively with fasting free fatty acids and negatively with dipeptidyl peptidase‐4 activity. Conclusions: Ethanol and solid‐phase extractions remove interference for intact GLP‐1 immunoassay. SU showed little effect on incretin secretion. GLP‐1 and GIP secretion were predicted by different factors. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2011.00141.x, 2012)  相似文献   
995.
Anti‐diabetic agent‐related hypoglycemia is a serious complication in type 2 diabetic patients on hemodialysis. Therefore, we assessed the efficacy and tolerability of 24 weeks of monotherapy with vildagliptin, a dipeptidyl peptidase four inhibitor, which is a new class of antidiabetic agent. This open‐label, single‐arm clinical trial was performed on 26 patients on hemodialysis. The primary assessments were changes in postprandial glucose level and glycated albumin (GA). During the study, three patients dropped out, and data from 23 patients were analyzed. Significant reductions were seen in postprandial glucose (−2.60 ± 3.80 mmol/L, P < 0.001) and GA (−2.59 ± 2.33%, P < 0.001) levels. No serious drug‐related adverse events were observed. Vildagliptin monotherapy can be recommended for glycemic control in type 2 diabetic patients on hemodialysis. This trial was registered with the University Hospital Medical Information Network (no. UMIN000003661). (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2011.00169.x, 2011)  相似文献   
996.
Aims/Introduction: Oral ingestion of carbohydrate triggers secretion of glucagon‐like peptide (GLP)‐1, which inhibits the postprandial rise in blood glucose levels. However, the mechanism of carbohydrate‐induced GLP‐1 secretion from enteroendocrine L cells remains unclear. In the present study, GLP‐1 secretion was examined by meal tolerance tests of healthy Japanese volunteers. Materials and Methods: Twenty‐one healthy Japanese men participated in the study. The meal tolerance test was performed with modified nutrient compositions, with or without pretreatment with the α‐glucosidase inhibitor acarbose, or with substitution of sucrose with an equivalent dose of sweeteners in the meal. Blood concentrations of glucose, insulin, GLP‐1, and apolipoprotein (Apo) B‐48 were measured. Results: GLP‐1 secretion started concomitant with the increase in blood glucose levels 10 min after meal ingestion. Insulin secretion started at 5 min, before the increase in blood glucose levels, reflecting the contribution of direct nutrient stimulation on the former parameter and neural regulation in the latter. Carbohydrate retention in the gut lumen induced by acarbose pretreatment extended postprandial GLP‐1 secretion and negated the increase in serum ApoB‐48 levels. GLP‐1 secretion was markedly decreased by a reduction in the amount of sucrose in the meal and was not restored by an equivalent dose of sweeteners used to compensate for the sweet taste. Conclusions: The results indicate that direct stimulation of L cells with sugar, but not sweetener, is required for carbohydrate‐induced GLP‐1 secretion. In addition, inhibition of digestion of dietary carbohydrate by α‐glucosidase inhibitors may prevent postprandial hyperglycemia by increasing GLP‐1 secretion and by inhibiting glucose absorption. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2011.00163.x, 2011)  相似文献   
997.
Breast cancer is the most common type of cancer in women. However, it is very rarely manifested as hematologic disorders. A 35-year-old woman was admitted because of disseminated intravascular coagulation. Examinations revealed the presence of breast cancer in her left breast; therefore, paclitaxel was administered weekly. Although disseminated intravascular coagulation was controlled, pulmonary dysfunction due to lymphangitis carcinomatosa suddenly occurred 10 weeks after treatment. Pulmonary dysfunction was effectively treated with epirubicin and cyclophosphamide. Twenty-three weeks after treatment, the patient developed liver dysfunction accompanied with jaundice due to progressive metastatic lesions in the liver; liver dysfunction improved after the administration of vinorelbine. Subsequently, because of the recurrence of pulmonary dysfunction, rechallenge with epirubicin and cyclophosphamide was performed and was effective; however, this therapy was discontinued because of its adverse effects. She expired of liver failure 33 weeks after the occurrence of disseminated intravascular coagulation. Metastatic tumors in the bone marrow, lung, and liver showed different sensitivities to different anti-cancer agents. We report a case of breast cancer manifested by hematologic disorders which was treated by a sequential chemotherapy.KEY WORDS : Breast cancer, disseminated intravascular coagulation, multiple organ metastases  相似文献   
998.

Purpose

To describe the feasibility of a dual microcatheter-dual interlocking detachable coil (DMDI) technique for preoperative embolization of the common hepatic artery (CHA) in preparation for distal pancreatectomy with en bloc celiac axis resection (DP-CAR) for locally advanced pancreatic body cancer.

Methods

From January 2007 to December 2009, 26 patients underwent embolization of the CHA by the DMDI technique. We compared the results with those of 37 patients in whom the CHA was embolized by conventional techniques from August 1998 to February 2007.

Results

With the DMDI technique, no coil migration or other embolization-related complications occurred. The success rate was 100%. The rate of embolization-related complications was significantly lower in the DMDI embolization group (0%) than in the conventional embolization group (24.3%) (P?=?0.008). The frequency of improper positioning of the embolic material necessitating its removal during DP-CAR was significantly lower in the DMDI embolization group (10%) than in the conventional embolization group (37.5%) (P?=?0.044).

Conclusion

The DMDI technique allows the development of collateral pathways, reduces the surgeon's burden in ligating the distal CHA, and prevents coil migration. For these reasons, we believe that this technique is feasible for embolization of the CHA in preparation for DP-CAR for locally advanced pancreatic body cancer.  相似文献   
999.
Interleukin (IL)‐10 is an anti‐inflammatory cytokine mainly produced by monocytes and is essential for the induction of anti‐inflammatory intestinal macrophages with macrophage colony‐stimulating factor (M‐CSF). Thus, IL‐10‐ and M‐CSF‐rich conditions in colonic tissues seem to contribute to the improvement of pathological conditions in patients with inflammatory bowel diseases (IBD). We have already reported that ulinastatin, a serine protease inhibitor, increases M‐CSF production during granulocyte/monocyte (GM) adsorption to cellulose acetate (CA) beads (carriers for Adacolumn therapy). However, the effects of ulinastatin on IL‐10 production have not been clarified. The aim of the present study was to clarify the effects of ulinastatin on IL‐10 production during GM adsorption by in vitro experiments. Peripheral blood was divided into four groups: (Control) no ulinastatin added, no contact with CA beads; (1) no ulinastatin added, contact with CA beads; (2) ulinastatin added, no contact with CA beads; and (3) ulinastatin added, contact with CA beads. After incubation, IL‐10 in the plasma was measured. Compared with the level in the Control group, plasma IL‐10 was significantly higher only in group 3, in which ulinastatin was added in the presence of CA beads, but did not increase in the absence of CA beads. These results suggest that ulinastatin synergistically increases IL‐10 production with monocyte adsorption stimuli. By increasing not only M‐CSF but also IL‐10, a combination of ulinastatin and Adacolumn therapy may improve clinical efficacy for the treatment of IBD in terms of the induction of anti‐inflammatory intestinal macrophages.  相似文献   
1000.
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