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   3893篇
  免费   267篇
  国内免费   100篇
耳鼻咽喉   14篇
儿科学   74篇
妇产科学   23篇
基础医学   730篇
口腔科学   65篇
临床医学   349篇
内科学   808篇
皮肤病学   304篇
神经病学   280篇
特种医学   117篇
外科学   454篇
综合类   39篇
一般理论   1篇
预防医学   139篇
眼科学   96篇
药学   413篇
中国医学   46篇
肿瘤学   308篇
  2024年   4篇
  2023年   22篇
  2022年   90篇
  2021年   129篇
  2020年   77篇
  2019年   95篇
  2018年   118篇
  2017年   110篇
  2016年   165篇
  2015年   213篇
  2014年   268篇
  2013年   300篇
  2012年   401篇
  2011年   359篇
  2010年   220篇
  2009年   185篇
  2008年   246篇
  2007年   226篇
  2006年   186篇
  2005年   164篇
  2004年   118篇
  2003年   101篇
  2002年   89篇
  2001年   40篇
  2000年   41篇
  1999年   24篇
  1998年   36篇
  1997年   34篇
  1996年   25篇
  1995年   17篇
  1994年   14篇
  1993年   15篇
  1992年   21篇
  1991年   20篇
  1990年   11篇
  1989年   16篇
  1988年   13篇
  1987年   13篇
  1986年   5篇
  1985年   6篇
  1979年   1篇
  1978年   1篇
  1977年   1篇
  1976年   4篇
  1975年   2篇
  1974年   2篇
  1973年   4篇
  1971年   2篇
  1970年   1篇
  1968年   2篇
排序方式: 共有4260条查询结果,搜索用时 11 毫秒
51.
52.
Cardiac involvement in Churg–Strauss syndrome (CSS) is a major cause of mortality. Here we report a case of a 75‐year‐old woman with eosinophilic endomyocarditis due to CSS. An electrocardiogram showed intraventricular conduction delay, and echocardiography showed an impaired relaxation pattern and biventricular apical thickening. Magnetic resonance imaging revealed subendocardial delayed enhancement with biventricular apical thrombi. Endomyocardial biopsy showed perivascular eosinophilic infiltration. Despite resolution of the hypereosinophilia after steroid therapy, her left ventricular (LV) diastolic function worsened into a restrictive pattern and she died with a ventricular escape rhythm on her 14th day in the hospital. This case is unusual in that there was rapid progression of the LV diastolic dysfunction and conduction disturbance due to CSS.  相似文献   
53.
BackgroundThe current position of robotic surgery in the field of minimally invasive surgery remains ambiguous. We evaluated long-term trends of robotic general surgery and the future direction of its development.MethodsData on robotic cancer surgeries between 2005 and 2014 were retrospectively collected by volunteer institutions in the Republic of Korea. Spearman's correlation and logistic regression analyses were used to compare robotic and laparoscopic surgery trends in general surgery.ResultsThe odds that robotic surgery was performed instead of laparoscopic surgery significantly decreased in the fields of colorectal, stomach, and hepato-biliary-pancreatic surgery (odds ratio [OR]: 0.95, 95% confidence interval [CI]: 0.93–0.97; OR: 0.90, 95% CI: 0.88–0.92; and OR: 0.71, 95% CI: 0.65–0.78, respectively), except for thyroid surgery (OR: 1.28, 95% CI: 1.25–1.30). Of the total numbers of each procedure, proportions of robotic intersphincteric resections, abdominoperineal resections, and pylorus-preserving surgery performed significantly increased (r = 0.98, P < .001; r = 0.78, P = .01; and r = 0.86, P = .007, respectively).ConclusionsThe use of robotic surgery failed to preponderate that of laparoscopic surgery, except for thyroid surgery. Robotic surgery is increasingly preferred for limited fields or complex surgeries, but the use of robotics in simple surgeries has decreased.  相似文献   
54.

Purpose

To compare the efficacy of lymph node (LN) embolization using N-butyl cyanoacrylate versus ethanol sclerotherapy in the management of symptomatic postoperative pelvic lymphorrhea.

Materials and Methods

Thirty-three patients with 40 instances of symptomatic postoperative lymphorrhea were treated with either LN embolization or sclerotherapy at Seoul National University Hospital from January 2009 to July 2017 and were retrospectively included (LN embolization group: 24 lymphoceles of 19 patients, mean age of 59.29 years; sclerotherapy group: 16 lymphoceles of 14 patients, mean age of 60.95 years). The types of operations were hysterectomy and bilateral oophorectomy with pelvic lymph node dissection (n = 9), radical prostatectomy (n = 3), and renal transplantation (n = 2) for the sclerotherapy group and radical prostatectomy (n = 10) and hysterectomy and bilateral oophorectomy with pelvic lymph node dissection (n = 9) for the LN embolization group. The 3 most common indications of treatment were lower extremity edema (n = 11), pain (n = 11), and fever (n = 8). The amount of leak before treatment (initial daily drainage) and clinical outcomes, including the clinical success rate in 3 weeks, treatment period, and complication rate were compared between both groups.

Results

LN embolization showed a higher 3-week clinical success rate than sclerotherapy in a univariate analysis (83.3% and 43.8%, P = .026). There was no statistically significant difference in the treatment period and the complication rate (7.1 days and 12.3 days, P = .098; 8.3% and 25.0%, P = .184).

Conclusions

LN embolization is more effective for treating postoperative pelvic lymphorrhea than sclerotherapy with similar safety.  相似文献   
55.
56.
Excessive dietary fat intake causes systemic metabolic toxicity, manifested in weight gain, hyperglycemia, and insulin resistance. In addition, carbohydrate utilization as a fuel is substantially inhibited. Correction or reversal of these effects during high-fat diet (HFD) intake is of exceptional interest in light of widespread occurrence of diet-associated metabolic disorders in global human populations. Here we report that mangiferin (MGF), a natural compound (the predominant constituent of Mangifera indica extract from the plant that produces mango), protected against HFD-induced weight gain, increased aerobic mitochondrial capacity and thermogenesis, and improved glucose and insulin profiles. To obtain mechanistic insight into the basis for these effects, we determined that mice exposed to an HFD combined with MGF exhibited a substantial shift in respiratory quotient from fatty acid toward carbohydrate utilization. MGF treatment significantly increased glucose oxidation in muscle of HFD-fed mice without changing fatty acid oxidation. These results indicate that MGF redirects fuel utilization toward carbohydrates. In cultured C2C12 myotubes, MGF increased glucose and pyruvate oxidation and ATP production without affecting fatty acid oxidation, confirming in vivo and ex vivo effects. Furthermore, MGF inhibited anaerobic metabolism of pyruvate to lactate but enhanced pyruvate oxidation. A key target of MGF appears to be pyruvate dehydrogenase, determined to be activated by MGF in a variety of assays. These findings underscore the therapeutic potential of activation of carbohydrate utilization in correction of metabolic syndrome and highlight the potential of MGF to serve as a model compound that can elicit fuel-switching effects.  相似文献   
57.
58.
Resistin is a protein secreted from adipose tissue that is thought to play a role in insulin sensitivity. We examined the effects of rosiglitazone and metformin on the plasma resistin levels in individuals with type 2 diabetes mellitus. Patients with type 2 diabetes mellitus who showed poor glycemic control with glimepiride (4 mg/d) were randomized to rosiglitazone (4 mg/d) and metformin (500 mg bid) treatment groups. All subjects continued glimepiride treatment as well. The plasma concentrations of resistin were measured at baseline and at 6 months of treatment for both groups. The anthropometric parameters, fasting plasma glucose, HbA1c, total cholesterol, triglyceride, high-density lipoprotein cholesterol, free fatty acids, and adiponectin concentrations were also measured. After 6 months of treatment, the reduction in plasma glucose levels was similar between the 2 groups. There were no significant changes in the lipid profiles of either group during the study period. The plasma resistin levels decreased in the rosiglitazone group (2.49 +/- 1.93 vs 1.95 +/- 1.59 ng/ml; P < .05) but increased in the metformin group (2.61 +/- 1.69 vs 5.13 +/- 2.81 ng/ml; P < .05). The plasma adiponectin concentrations were increased in the rosiglitazone group (2.91 +/- 1.46 vs 4.23 +/- 1.77 microg/ml; P < .05) but were unchanged in the metformin group. In summary, rosiglitazone treatment decreased the plasma resistin levels whereas metformin treatment increased them in patients with type 2 diabetes mellitus showing poor glycemic control with sulfonylurea therapy. These results suggest that the observed changes in plasma resistin levels are not the consequences of improved insulin resistance, nor are they consequences of glycemic control. Considering the potential role of resistin in insulin resistance, decrease in resistin levels may contribute to improving insulin action with rosiglitazone treatment.  相似文献   
59.
Small cell carcinoma is usually seen in the lung, but rarely involves the gastrointestinal tract including biliary tract. A 65 year-old man was admitted because of obstructive jaundice. A smooth-surfaced round intraluminal mass with proximal bile duct dilatation was seen in the proximal common bile duct on endoscopic retrograde cholangiogram. Under the diagnosis of bile duct cancer, pylorus-preserving pancreatoduodenectomy was done. Pathology revealed a 2 cm sized small cell carcinoma in the proximal common bile duct and distal common hepatic duct. On immunohistochemical stain, the tumor cells were positive for neuroendocrine markers CD56 and synaptophysin. After surgery, the patient received 5 cycles of adjuvant chemotherapy with VIP (etoposide, ifosfamide, and cisplatin) regimen. However, the patient died of liver metastasis 12 months after the diagnosis. We report a case of extrapulmonary small cell carcinoma arising from the common bile duct.  相似文献   
60.
Lee  SB; Rao  AK; Lee  KH; Yang  X; Bae  YS; Rhee  SG 《Blood》1996,88(5):1684-1691
Platelets from a patient with a mild inherited bleeding disorder and abnormal platelet aggregation and secretion show reduced generation of inositol 1,4,5-trisphosphate, mobilization of intracellular Ca2+, and phosphorylation of pleckstrin in response to several G protein mediated agonists, suggesting a possible defect at the level of phospholipase C (PLC) activation (see accompanying report). A procedure was developed that allows quantitation of platelet PLC isozymes. After fractionation of platelet extracts by high-performance liquid chromatography, 7 out of 10 known PLC isoforms were detected by immunoblot analysis. The amount of these isoforms in normal platelets decreased in the order PLC- gamma 2 > PLC-beta 2 > PLC-beta 3 > PLC-beta 1 > PLC-gamma 1 > PLC- delta 1 > PLC-beta 4. Compared with normal platelets, platelets from the patient contained approximately one-third the amount of PLC-beta 2, whereas PLC-beta 4 was increased threefold. These results suggest that the impaired platelet function in the patient in response to multiple G protein mediated agonists is attributable to a deficiency of PLC-beta 2. They document for the first time a specific PLC isozyme deficiency in human platelets and provide an unique opportunity to understand the role of different PLC isozymes in normal platelet function.  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