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   527篇
  免费   26篇
  国内免费   2篇
耳鼻咽喉   20篇
儿科学   25篇
妇产科学   6篇
基础医学   64篇
口腔科学   8篇
临床医学   21篇
内科学   96篇
皮肤病学   22篇
神经病学   12篇
特种医学   17篇
外科学   101篇
综合类   17篇
预防医学   22篇
眼科学   13篇
药学   51篇
中国医学   6篇
肿瘤学   54篇
  2023年   2篇
  2022年   7篇
  2021年   14篇
  2020年   15篇
  2019年   10篇
  2018年   14篇
  2017年   13篇
  2016年   17篇
  2015年   20篇
  2014年   14篇
  2013年   15篇
  2012年   47篇
  2011年   47篇
  2010年   17篇
  2009年   17篇
  2008年   39篇
  2007年   26篇
  2006年   27篇
  2005年   18篇
  2004年   25篇
  2003年   7篇
  2002年   17篇
  2001年   15篇
  2000年   16篇
  1999年   15篇
  1998年   6篇
  1997年   6篇
  1995年   2篇
  1994年   2篇
  1993年   1篇
  1992年   6篇
  1991年   6篇
  1990年   7篇
  1989年   11篇
  1988年   4篇
  1987年   4篇
  1986年   4篇
  1985年   4篇
  1984年   5篇
  1983年   9篇
  1982年   2篇
  1979年   2篇
排序方式: 共有555条查询结果,搜索用时 15 毫秒
1.
2.
3.
The co-existence of fungal elements in allergic nasal Polyposis, has given rise to a distinct clinical entity known as ‘Allergic fungal sinusitis ’ (AF’S). Many a time, these fungal elements may not be diagnosed pre-operatively by routine diagnostic nasal endoscopy or CT scan of paranasal sinuses, due to the florid presentation of nasal polyps, which usually obscure the underlying fungal pathology. The diagnosis is often made intra-operatively. The post-operative confirmation of AFS is by histopathology, fungal smear, fungal culture, allergic murin study and fungal specific IgE titres. We report a series often such cases done in our institution, which highlight that AFS should be considered as a differential diagnosis in Sinonasal Polyposis cases, for their effective management.  相似文献   
4.
A two and half year old male child was seen with systemic hypertension, left ventricular dysfunction, mitral regurgitation and congestive cardiac failure. Examination revealed adenoid hypertrophy. He was also suffering from obstructive sleep apnea. He was being treated with anti-hypertensive and anti-failure drugs. Adenoidectomy was performed following which obstructive sleep apnea symptoms disappeared and his cardiac status improved markedly. Subsequently he was weaned off anti-hypertensive and anti-failure therapy.  相似文献   
5.
6.
Chemotherapy for primary or metastatic hepatic malignancy is limited by poor tumor response and dose-related systemic toxicity. As an alternative to chemotherapy infusion by vein or by the hepatic artery, the authors have developed a percutaneous technique of isolated liver perfusion that allows the regional delivery of high-dose chemotherapy to the liver with little systemic toxicity. After placement of a hepatic artery infusion catheter, an 18-F double-balloon catheter is placed into the inferior vena cava through the opposite femoral vein. Balloons are inflated above and below the hepatic veins, thus isolating hepatic venous outflow. The effluent passes through fenestrations in the catheter and is pumped through charcoal hemoperfusion filters where the drug is removed. The filtered blood is returned to the patient through the internal jugular vein. Fifteen treatments have been conducted in eight patients in a phase I dose-escalation study with use of 5-fluorouracil (5-FU). While it is premature to assess tumor response to isolated liver perfusion, the data demonstrate that the procedure is safe and is tolerated by patients. Pharmacokinetic studies show a 5-FU extraction of up to 85%, with minimal drug leakage into the systemic circulation. This technique shows potential for improving liver tumor response while decreasing systemic toxicity.  相似文献   
7.
The natural product quercetin is a flavonoid found in many fruits and vegetables. Previous research has shown that quercetin has antitumor, anti-inflammatory, antiallergic, and antiviral activities. In the present investigation we studied the effect of quercetin on the ability of prostate cancer cell lines with various degrees of aggressive potential to form colonies in vitro. Specifically, we examined the molecular mechanisms underlying this effect, including the expression of cell cycle and tumor suppressor genes as well as oncogenes. We observed that quercetin at concentrations of 25 and 50 μM significantly inhibited the growth of the highly aggressive PC-3 prostate cancer cell line and the moderately aggressive DU-145 prostate cancer cell line, whereas it did not affect colony formation by the poorly aggressive LNCaP prostate cancer cell line or the normal fibroblast cell line BG-9. Using the gene array methodology, we found that quercetin significantly inhibited the expression of specific oncogenes and genes controlling G1, S, G2, and M phases of the cell cycle. Moreover, quercetin reciprocally up-regulated the expression of several tumor suppressor genes. In conclusion, our results demonstrate that the antitumor effects of quercetin directly correlate with the aggressive potential of prostate cancer cells and that the mechanism(s) of quercetin-mediated antitumor effects may involve up-regulation of tumor suppressor genes and reciprocal down-regulation of oncogenes and cell cycle genes. The results of these studies provide a scientific basis for the potential use of flavonoids as nutraceuticals in the chemoprevention of cancer.  相似文献   
8.
The natural product quercetin is a flavonoid found in many fruits and vegetables. Previous research has shown that quercetin has antitumor, anti-inflammatory, antiallergic, and antiviral activities. In the present investigation we studied the effect of quercetin on the ability of prostate cancer cell lines with various degrees of aggressive potential to form colonies in vitro. Specifically, we examined the molecular mechanisms underlying this effect, including the expression of cell cycle and tumor suppressor genes as well as oncogenes. We observed that quercetin at concentrations of 25 and 50 micro M significantly inhibited the growth of the highly aggressive PC-3 prostate cancer cell line and the moderately aggressive DU-145 prostate cancer cell line, whereas it did not affect colony formation by the poorly aggressive LNCaP prostate cancer cell line or the normal fibroblast cell line BG-9. Using the gene array methodology, we found that quercetin significantly inhibited the expression of specific oncogenes and genes controlling G(1), S, G(2), and M phases of the cell cycle. Moreover, quercetin reciprocally up-regulated the expression of several tumor suppressor genes. In conclusion, our results demonstrate that the antitumor effects of quercetin directly correlate with the aggressive potential of prostate cancer cells and that the mechanism(s) of quercetin-mediated antitumor effects may involve up-regulation of tumor suppressor genes and reciprocal down-regulation of oncogenes and cell cycle genes. The results of these studies provide a scientific basis for the potential use of flavonoids as nutraceuticals in the chemoprevention of cancer.  相似文献   
9.
The efficacy of supravital staining in the detection of malignancies in oro and oropharyngeal lesions and its role in the detection of malignant changes in premalignant lesions were studied. This prospective study comprises 90 cases of clinically suspicious lesions and it was done over a period of 3 years. Most of the patients had multiple risk factors for the development of malignancy. All underwent staining with a modified solution of 1% toluidine blue (TB). In our study the overall sensitivity was 97.29% and the specificity was 62.5%.  相似文献   
10.
ObjectiveTo investigate the antibacterial potential of 5 different metal oxide nanoparticles against antibiotic resistant bacterial pathogens viz., Pseudomonas aeruginosa, Klebsiella sp. Streptococcus pneumoniae, Staphylococcus aureus and Streptococcus sp.MethodsThe antibacterial activity of the five different nanoparticles was assessed by well diffusion method. Different concentrations of the nanoparticles were analyzed by MIC and MBC techniques. Finally the potential MgO nanoparticle was also subjected for the time kill assay method.ResultsThe results reveal that, the MgO nanoparticle showed maximum sensitivity [(16.00±0.53) mm dia] against Streptococcus pneumoniae and showed minimum sensitivity against Klebsiella sp. [(9.00±0.31) mm dia]. None of the nanoparticles showed sensitivity against the Streptococcus sp. The MIC result reveals that, the MgO nanoparticle showed maximum inhibition at a concentration of 10 μ g against Streptococcus pneumoniae. Moreover, the time kill assay reveals that, the bacterial growth was inhibited from the 2nd h onwards at a concentration of 10μ g.ConclusionsIt is concluded from the present findings that, the MgO nanoparticle could be used as an alternative antibacterial agent after completing successful in vivo trials.  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