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   1751篇
  免费   67篇
  国内免费   11篇
耳鼻咽喉   2篇
儿科学   78篇
妇产科学   18篇
基础医学   193篇
口腔科学   12篇
临床医学   109篇
内科学   398篇
皮肤病学   44篇
神经病学   32篇
特种医学   122篇
外科学   165篇
综合类   294篇
预防医学   66篇
眼科学   35篇
药学   153篇
中国医学   5篇
肿瘤学   103篇
  2022年   13篇
  2021年   22篇
  2020年   14篇
  2019年   21篇
  2018年   25篇
  2017年   20篇
  2016年   23篇
  2015年   36篇
  2014年   32篇
  2013年   47篇
  2012年   67篇
  2011年   53篇
  2010年   84篇
  2009年   58篇
  2008年   79篇
  2007年   81篇
  2006年   91篇
  2005年   70篇
  2004年   92篇
  2003年   46篇
  2002年   48篇
  2001年   44篇
  2000年   47篇
  1999年   53篇
  1998年   44篇
  1997年   56篇
  1996年   56篇
  1995年   33篇
  1994年   30篇
  1993年   12篇
  1992年   32篇
  1991年   20篇
  1990年   22篇
  1989年   19篇
  1988年   26篇
  1987年   21篇
  1986年   19篇
  1985年   20篇
  1984年   22篇
  1982年   13篇
  1981年   20篇
  1979年   13篇
  1978年   15篇
  1976年   12篇
  1975年   11篇
  1974年   18篇
  1971年   10篇
  1970年   14篇
  1969年   10篇
  1968年   17篇
排序方式: 共有1829条查询结果,搜索用时 15 毫秒
51.
A 23-year-old female with an echinococcal cyst in the atrioventricular groove of the heart is reported. The diagnosis and the location of the cyst were confirmed by echocardiography and cardiac catheter. Successful enucleating of the cyst with the aid of cardiopulmonary bypass and the length of follow-up is reported, along with a review of relevant literature.  相似文献   
52.
53.
Malignant phyllodes tumour is an uncommon breast neoplasm which undergoes osteosarcomatous differentiation in 1.3% of cases. We document the plain film, CT and scintigraphic features of a case of pulmonary metastases from this rare primary tumour.  相似文献   
54.
Protection of the thiolate function of dimercaptosuccinic acid (DMSA) and ethylenedi‐l ‐cysteine diethyl ester (ECD) by S‐thiomethylation allowed automatic deprotection during technetium‐99m (99mTc) radiolabelling by direct reduction with stannous chloride dihydrate. Protection of the free thiolate group increased the stability of the ligands as well as deprotection during complexation, which resulted in the desired radiopharmaceuticals. The complexes obtained from the protected ligands were chromatographically (HPLC) and biologically compared with the corresponding 99mTc complexes of the unprotected ligands. The results suggest that the aforementioned method of protection by S‐thiomethylation could be utilized for the development of single‐vial DMSA and ECD kit. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
55.
Annular elastolytic giant cell granuloma is a condition characterized histologically by damaged elastic fibers associated with preponderance of giant cells along with absence of necrobiosis, lipid, mucin, and pallisading granuloma. It usually occurs on sun-damaged skin and hence the previous name actinic granuloma. A similar process occurs on the conjunctiva. Over the past three decades only four cases of conjunctival actinic granuloma have been documented. All the previous patients were females with lesions in nasal or temporal bulbar conjunctiva varying 2-3 mm in size. We report a male patient aged 70 years presenting with a 14 mm × 7 mm fleshy mass on right lower bulbar conjunctiva. Clinical differential diagnoses were lymphoma, squamous cell carcinoma in situ and amyloidosis. Surgical excision followed by histopathology confirmed it to be a case of actinic granuloma. This is the first case of isolated conjunctival actinic granuloma of such a large size reported from India.  相似文献   
56.
Foot‐and‐mouth disease (FMD) is endemic in India and causes severe economic loss. Status of FMD in the country for five fiscal years is presented. Outbreaks were more in number in 2007–2008 than 2010–2011. Three serotypes of FMD virus (O, A and Asia1) are prevalent. Serotype O was responsible for 80% of the confirmed outbreaks/cases, whereas Asia1 and A caused 12% and 8%, respectively. Geographical region‐wise assessment indicated varying prevalence rate in different regions viz; 43% in Eastern region, 31.5% in Southern region, 11.6% in North‐eastern region, 5% Central region, 4.4% Western region and 4% in Northern region. Highest number of outbreaks/cases was recorded in the month of September and lowest in June. Emergence and re‐emergence of different genotypes/lineages within the serotypes were evident in real‐time investigation carried out from time to time. Continues antigenic divergence in serotype A resulted in change in the vaccine strain in 2009. As on date, all genetic diversity within the serotypes is well tolerated by the vaccine strains. Unrestricted animal movements in the country play a major role in the spread of FMD.  相似文献   
57.
Prion diseases are fatal neurodegenerative diseases affecting mammals. Prions are misfolded amyloid aggregates of the prion protein (PrP), which form when the alpha helical, soluble form of PrP converts to an aggregation-prone, beta sheet form. Thus, prions originate as protein folding problems. The discovery of yeast prion(s) and the development of a red-/white-colony based assay facilitated safe and high-throughput screening of antiprion compounds. With this assay three antiprion compounds; 6-aminophenanthridine (6AP), guanabenz acetate (GA), and imiquimod (IQ) have been identified. Biochemical and genetic studies reveal that these compounds target ribosomal RNA (rRNA) and inhibit specifically the protein folding activity of the ribosome (PFAR). The domain V of the 23S/25S/28S rRNA of the large ribosomal subunit constitutes the active site for PFAR. 6AP and GA inhibit PFAR by competition with the protein substrates for the common binding sites on the domain V rRNA. PFAR inhibition by these antiprion compounds opens up new possibilities for understanding prion formation, propagation and the role of the ribosome therein. In this review, we summarize and analyze the correlation between PFAR and prion processes using the antiprion compounds as tools.  相似文献   
58.
59.
60.
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