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   8033篇
  免费   566篇
  国内免费   31篇
耳鼻咽喉   136篇
儿科学   303篇
妇产科学   188篇
基础医学   1110篇
口腔科学   126篇
临床医学   720篇
内科学   1465篇
皮肤病学   97篇
神经病学   900篇
特种医学   222篇
外科学   1131篇
综合类   107篇
一般理论   15篇
预防医学   576篇
眼科学   209篇
药学   572篇
中国医学   10篇
肿瘤学   743篇
  2023年   89篇
  2022年   180篇
  2021年   266篇
  2020年   188篇
  2019年   212篇
  2018年   264篇
  2017年   221篇
  2016年   242篇
  2015年   255篇
  2014年   327篇
  2013年   422篇
  2012年   626篇
  2011年   537篇
  2010年   352篇
  2009年   262篇
  2008年   399篇
  2007年   441篇
  2006年   389篇
  2005年   351篇
  2004年   342篇
  2003年   323篇
  2002年   326篇
  2001年   131篇
  2000年   109篇
  1999年   133篇
  1998年   63篇
  1997年   58篇
  1996年   44篇
  1995年   38篇
  1994年   29篇
  1993年   29篇
  1992年   71篇
  1991年   63篇
  1990年   55篇
  1989年   68篇
  1988年   51篇
  1987年   52篇
  1986年   50篇
  1985年   58篇
  1984年   42篇
  1983年   35篇
  1982年   34篇
  1981年   28篇
  1979年   48篇
  1978年   26篇
  1977年   25篇
  1976年   25篇
  1975年   22篇
  1973年   27篇
  1972年   27篇
排序方式: 共有8630条查询结果,搜索用时 15 毫秒
91.
92.
Most intra-abdominal and other types of fluid collections are now successfully drained percutaneously under image guidance. The utility of percutaneous drainage of tuberculous abscesses, especially those associated with osseous changes, is, however, less well established. Six patients with tuberculous iliopsoas abscesses were successfully managed by percutaneous drainage combined with antituberculous therapy. The abscesses were bilateral in one patient and unilateral in the other five. Drainage was by needle aspiration under ultrasound (US) guidance in one patient, and by catheter under CT guidance in the other patients. Three patients had associated osseous changes. There were no procedural complications. Tuberculous iliopsoas abscess can be successfully treated by percutaneous drainage and appropriate antituberculous therapy.  相似文献   
93.

Background

We have previously reported that children receive significantly less radiation exposure after abdominal and/or pelvis computed tomography (CT) scanning for acute appendicitis when performed at our children's hospital (CH) rather than at outside hospitals (OH). In this study, we compare the amount of radiation children receive from head CTs for trauma done at OH versus those at our CH.

Methods

A retrospective chart review was performed on all children transferred to our hospital after receiving a head CT for trauma at an OH between July 2012 and December 2012. These children were then blindly case matched based on date, age, and gender to children at our CH.

Results

There were 50 children who underwent head CT scans for trauma at 28 OH. There were 21 females and 29 males in each group. Average age was 7.01 ± 0.5 y at the OH and 7.14 ± 6.07 at our CH (P = 0.92). Average weight was 30.81 ± 4.69 kg at the OH and 32.69 ± 27.21 kg at our CH (P = 0.81). Radiation measures included dose length product (671.21 ± 22.6 mGycm at OH versus 786.28 ± 246.3 mGycm at CH, P = 0.11) and CT dose index (53.4 ± 2.26 mGy at OH versus 49.2 ± 12.94 mGy at CH, P = 0.56).

Conclusions

There is no significant difference between radiation exposure secondary to head CTs for traumatic injuries performed at OH and those at a dedicated CH.  相似文献   
94.
IntroductionAngiopoietin-2 (Ang-2) is a novel marker of coronary artery disease (CAD) and diabetes (DM). The aim was to evaluate Ang-2 as a potential new biomarker of non-ST elevation myocardial infarction (NSTEMI) in patients with or without type 2 DM (T2DM).Material and methodsThis was a multi-center, prospective study that included 138 (males: 91/66%) consecutive patients hospitalized due to NSTEMI, T2DM, or different cardiac disorders. The subjects were divided into four study groups: group A: 28 patients with NSTEMI and T2DM; group B: 47 patients with NSTEMI without T2DM; group C: 31 patients with T2DM, without a history of CAD; group D: 32 patients as a control group. Patients with NSTEMI underwent urgent coronarography. Clinical characteristics including biomarkers (hs-CRP, hsTnT, NT-proBNP, VEGF, HbA1c), SYNTAX SCORE, type of intervention (PCI vs. CABG), and number of implanted stents were taken into account in the analysis.ResultsSerum Ang-2 concentrations were significantly higher in patients with NSTEMI (group A: 1769 pg/ml; group B: 1757 pg/ml) and patients with T2DM (group C: 1993 pg/ml) as compared to the patients without CAD and without T2DM (group D: 866.8 pg/ml; p < 0.05). The prognostic accuracy of Ang-2 in NSTEMI diagnosis was determined with the area under the ROC curve (area under curve (AUC) = 0.63).ConclusionsAngiopoietin-2 serum concentration is elevated in the presence of NSTEMI in patients with and without T2DM and does not correspond to the degree of myocardial injury and hemodynamic status. Ang-2 remains elevated also in patients with T2DM without a history of CAD.  相似文献   
95.
Curcumin inhibits UDP‐glucuronyltransferases, a primary metabolic pathway for cancer chemotherapeutic agents like irinotecan. Concurrent administration of both agents may exacerbate irinotecan toxicity. We conducted this phase I study to determine the safety of concurrent curcumin and irinotecan administration. Ten participants with advanced solid tumors received one of four doses (1, 2, 3, and 4 g) of a curcumin phosphatidylcholine complex (PC) orally daily, and 200 mg/m2 of i.v. infusion irinotecan on days 1 and 15 of a 28‐day cycle, to determine the maximum tolerated dose (MTD) of PC. Thirteen participants received 4 g of PC (MTD) to assess the effect on the pharmacokinetic (PK) properties of irinotecan and its metabolites, SN‐38 and SN‐38G. Irinotecan, SN‐38, and SN‐38G exposure equivalence with and without curcumin was assessed using area under the plasma concentration‐time curves from 0 to 6 h (AUC0‐6h). Safety assessments and disease responses were also evaluated. The combination of irinotecan and PC was well‐tolerated. Because there was no dose limiting toxicity, the maximum dose administered (4 g) was defined as the recommended phase II dose of PC. PC did not significantly alter the plasma exposure and other PK properties of irinotecan and its metabolites. There was no apparent increase in the incidence of irinotecan‐associated toxicities. The objective response rate was 3/19 (22%, 95% confidence interval [CI]: 5–39%), median progression free survival and overall survival (n = 23) were 4 months (95% CI: 2.9–8.9 months) and 8.4 months (95% CI: 3.7 – not evaluable [NE]), respectively. Future studies are required to evaluate the efficacy of this combination.

Study Highlights
  • WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?
Curcumin can be safely administered with some standard chemotherapy agents like gemcitabine, taxanes, and 5‐fluorouracil.
  • WHAT QUESTION DID THIS STUDY ADDRESS?
Both curcumin and irinotecan are metabolized by UGT enzymes and concurrent administration may affect the pharmacokinetics (PKs) and clinical effect of irinotecan. This study sought to assess the effect of curcumin on the PK properties and adverse effect profile of irinotecan.
  • WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?
Up to 4 g of a phosphatidylcholine curcumin (PC) formulation can be safely administered with irinotecan without an impact on the PK and adverse event profile of irinotecan.
  • HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?
Curcumin’s anticancer properties have been documented. Higher doses of PC can be investigated to determine a dose that acts synergistically with irinotecan to improve clinical outcomes.  相似文献   
96.
97.
98.
The MYC genes are the most frequently activated oncogenes in human tumors and are hence attractive therapeutic targets. MYCN amplification leads to poor clinical outcome in childhood neuroblastoma, yet strategies to modulate the function of MYCN do not exist. Here we show that 10058-F4, a characterized c-MYC/Max inhibitor, also targets the MYCN/Max interaction, leading to cell cycle arrest, apoptosis, and neuronal differentiation in MYCN-amplified neuroblastoma cells and to increased survival of MYCN transgenic mice. We also report the discovery that inhibition of MYC is accompanied by accumulation of intracellular lipid droplets in tumor cells as a direct consequence of mitochondrial dysfunction. This study expands on the current knowledge of how MYC proteins control the metabolic reprogramming of cancer cells, especially highlighting lipid metabolism and the respiratory chain as important pathways involved in neuroblastoma pathogenesis. Together our data support direct MYC inhibition as a promising strategy for the treatment of MYC-driven tumors.  相似文献   
99.
100.
Excessive activity of NADPH oxidase (Nox) is considered to be of importance for the progress of diabetic nephropathy. The aim of the study was to elucidate the effect of melatonin, known for its nephroprotective properties, on Nox activity under diabetic conditions. The experiments were performed on three groups of animals: (i) untreated lean (?/+) Zucker diabetic fatty (ZDF) rats; (ii) untreated obese diabetic (fa/fa) ZDF rats; and (iii) ZDF fa/fa rats treated with melatonin (20 mg/L) in drinking water. Urinary albumin excretion was measured weekly. After 4 wk of the treatment, the following parameters were determined in kidney cortex: Nox activity, expression of subunits of the enzyme, their phosphorylation and subcellular distribution. Histological studies were also performed. Compared to ?/+ controls, ZDF fa/fa rats exhibited increased renal Nox activity, augmented expression of Nox4 and p47phox subunits, elevated level of p47phox phosphorylation, and enlarged phospho‐p47phox and p67phox content in membrane. Melatonin administration to ZDF fa/fa rats resulted in the improvement of renal functions, as manifested by considerable attenuation of albuminuria and some amelioration of structural abnormalities. The treatment turned out to nearly normalize Nox activity, which was accompanied by considerably lowered expression and diminished membrane distribution of regulatory subunits, that is, phospho‐p47phox and p67phox. Thus, it is concluded that: (i) melatonin beneficial action against diabetic nephropathy involves attenuation of the excessive activity of Nox; and (ii) the mechanism of melatonin inhibitory effect on Nox is based on the mitigation of expression and membrane translocation of its regulatory subunits.  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