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   504篇
  免费   49篇
  国内免费   2篇
耳鼻咽喉   4篇
儿科学   11篇
妇产科学   23篇
基础医学   84篇
口腔科学   17篇
临床医学   37篇
内科学   133篇
皮肤病学   44篇
神经病学   64篇
特种医学   12篇
外科学   35篇
综合类   3篇
一般理论   1篇
预防医学   35篇
眼科学   16篇
药学   17篇
肿瘤学   19篇
  2024年   1篇
  2023年   4篇
  2022年   12篇
  2021年   28篇
  2020年   13篇
  2019年   14篇
  2018年   18篇
  2017年   14篇
  2016年   20篇
  2015年   22篇
  2014年   26篇
  2013年   37篇
  2012年   28篇
  2011年   38篇
  2010年   18篇
  2009年   15篇
  2008年   17篇
  2007年   20篇
  2006年   26篇
  2005年   18篇
  2004年   30篇
  2003年   18篇
  2002年   20篇
  2001年   11篇
  2000年   9篇
  1999年   9篇
  1998年   6篇
  1997年   8篇
  1996年   3篇
  1995年   2篇
  1994年   2篇
  1993年   7篇
  1992年   7篇
  1991年   5篇
  1990年   5篇
  1989年   7篇
  1988年   3篇
  1987年   3篇
  1986年   1篇
  1985年   3篇
  1984年   2篇
  1983年   1篇
  1982年   2篇
  1980年   1篇
  1974年   1篇
排序方式: 共有555条查询结果,搜索用时 15 毫秒
1.
2.
Summary In June 1989, two trains exploded when passing over the trans-Ural natural gas pipeline. Eight hundred people were badly burned and between 1500–3000 people died. International assistance was requested by the Soviet government, and the Israel Army Medical Corps assistance delegation treated 40 burned patients who were transferred to the Sklifosovsky Trauma Center in Moscow. Fifteen of them suffered second degree burns with a BSA between 15% to 60%, and were treated with the skin substitute omiderm. Ten days after the application of the dressing, the wounds were epithelized and the patients discharged. The advantages of the omiderm as a skin substitute in second degree burns are described and its usefulness in mass burn casualties emphasized.  相似文献   
3.
4.
General mechanisms by which Hox genes establish cell fates are known. However, a few Hox effectors mediating cell behaviors have been identified. Here we found the first effector of LIN-39/HoxD4/Dfd in Caenorhabditis elegans. In specific vulval precursor cells (VPCs), LIN-39 represses early and late expression of EFF-1, a membrane protein essential for cell fusion. Repression of eff-1 is also achieved by the activity of CEH-20/Exd/Pbx, a known cofactor of Hox proteins. Unfused VPCs in lin-39(-);eff-1(-) double mutants fail to divide but migrate, executing vulval fates. Thus, lin-39 is essential for inhibition of EFF-1-dependent cell fusion and stimulation of cell proliferation during vulva formation. Supplemental material is available at http://www.genesdev.org.  相似文献   
5.
6.
Trio exome sequencing is a powerful tool in the molecular investigation of monogenic disorders and provides an incremental diagnostic yield over proband‐only sequencing, mainly due to the rapid identification of de novo disease‐causing variants. However, heterozygous variants inherited from unaffected parents may be inadvertently dismissed, although multiple explanations are available for such scenarios including mosaicism in the parent, incomplete penetrance, imprinting, or skewed X‐inactivation. We report three probands, in which a pathogenic or likely pathogenic variant was identified upon exome sequencing, yet was inherited from an unaffected parent. Segregation of the variants (in NOTCH1, PHF6, and SOX10) in the grandparent generation revealed that the variant was de novo in each case. Additionally, one proband had skewed X‐inactivation. We discuss the possible genetic mechanism in each case, and urge caution in data interpretation of exome sequencing data. We illustrate the utility of expanding segregation studies to the grandparent generation and demonstrate the impact on exome interpretation strategies, by showing that objective genotype data can overcome subjective parental report of lack of symptoms.  相似文献   
7.
Summary Specific insulin receptors are present in the liver and brain of the lizard Anolis carolinesis. In this study, the specific binding of 125I-insulin to the receptors showed time, temperature and pH dependency. Specific binding to crude membranes prepared from brain was 1–2% of the total radioactivity added compared to 4–5% in the crude membranes prepared from liver. Solubilization and wheat germ agglutinin purification of the membranes resulted in an increase in the specific binding (per mg of protein) between 6 and 32 times for liver membranes and 13–186 for brain membranes. Binding inhibition of tracer insulin by unlabeled porcine insulin was characteristic for insulin receptors with 50% inhibition for liver crude membranes at 60 ng/ml of porcine insulin and 0.7 ng/ml for purified brain insulin receptors. Chicken insulin was 2- to 3-fold more potent and proinsulin about 100 times less potent than porcine insulin. The -subunits of liver and brain had apparent molecular weights on sodium dodecyl sulfate polyacrylamide gel electrophoresis of 135 kDa and 120 kDa respectively. Apparent molecular weights of subunits were 92 kDa for both tissues. Insulin stimulated phosphorylation of the subunit of both brain and liver receptors. Both tissues demonstrated tyrosine-specific phosphorylation, which was stimulated by insulin, of exogenously added artificial substrates. In addition, purified brain insulin receptor preparations contained an endogenous protein with apparent molecular weight of 105 kDa, whose phosphorylation was stimulated by insulin (10–7 mol/l). This phosphoprotein was not immunoprecipitated by anti-insulin receptor antibodies. These studies suggest that the structural differences between brain and liver receptors previously demonstrated in the rat are also present in the lizard, which is about 300,000,000 years older than the mammalian species. Thus, there is strong evolutionary conservation of the brain insulin receptor.  相似文献   
8.
BackgroundIncreasing cancer incidence among children alongside improved treatments has resulted in a growing number of pediatric cancer survivors. Despite childhood cancer survivors’ exposure to various factors that compromise kidney function, few studies have investigated the association between childhood cancer and future kidney disease.MethodsTo assess the risk of ESKD among childhood cancer survivors, we conducted a nationwide, population-based, retrospective cohort study that encompassed all Israeli adolescents evaluated for mandatory military service from 1967 to 1997. After obtaining detailed histories, we divided the cohort into three groups: participants without a history of tumors, those with a history of a benign tumor (nonmalignant tumor with functional impairment), and those with a history of malignancy (excluding kidney cancer). This database was linked to the Israeli ESKD registry to identify incident ESKD cases. We used Cox proportional hazards models to estimate the hazard ratio (HR) of ESKD.ResultsOf the 1,468,600 participants in the cohort, 1,444,345 had no history of tumors, 23,282 had a history of a benign tumor, and 973 had a history of malignancy. During a mean follow-up of 30.3 years, 2416 (0.2%) participants without a history of tumors developed ESKD. Although a history of benign tumors was not associated with an increased ESKD risk, participants with a history of malignancy exhibited a substantially elevated risk for ESKD compared with participants lacking a history of tumors, after controlling for age, sex, enrollment period, and paternal origin (adjusted HR, 3.2; 95% confidence interval, 1.3 to 7.7).ConclusionsChildhood cancer is associated with an increased risk for ESKD, suggesting the need for tighter and longer nephrological follow-up.  相似文献   
9.
BACKGROUND: The arbovirus infections West Nile fever (WNF) and sandfly fever (SFF) are both endemic in the Middle East. Despite the fact that the mosquito and sandfly vectors of these viruses are still found in Israel, SFF has not been reported since 1948, whereas outbreaks of WNF occur periodically. It is suspected that some of the cases of nonspecific febrile illnesses in Israel may in fact be either WNF or SFF. AIM: To determine the extent of past arbovirus infections in subgroups of Israeli soldiers. METHODS: Sera from random samples of three groups of healthy soldiers aged 18-20 (n=273), 21-30 (n=497), and 40-55 years (n=285) were examined for IgG and IgM antibodies to West Nile virus (WNV), sandfly fever Sicilian virus (SFSV), and sandfly fever Naples virus (SFNV), using an ELISA method. RESULTS: The prevalence of antibodies increased with age for all three viruses examined, and ranged from 7.0%, 0, and 2.8%, for WNV, SFSV, AND SFNV, respectively, in soldiers aged 18-20 years, to 41.9%, 23.7%, and 30.8%, in those aged 40-55 years. The percentage of seropositives for IgG who were also IgM positive were 1.0%, 5.9%, and 3.4%, for WNV, SFSV, AND SFNV, respectively. 17.5% of the seropositives for WNV were also positive for SFSV, as compared with 5.7% among the WNV-seronegatives. Among the seropositives for WNV, 23.99% were positive for SFNV, compared with 9.1% of WNV seronegatives. 48.2% of seropositives for SFSV were positive for SFNV, as compared with 8.4% for SFSV-seronegatives. In the age agroup 40-55 years, there were significantly higher prevalence rates in those born in Israel compared with those born abroad. CONCLUSIONS: There is still significant exposure to WNV, SFSV, and SFNV in Israel. Arborviruses are probably responsible for many cases of non-specific febrile illness in this region.  相似文献   
10.
The aim of the present study was to assess the post-smallpox vaccination complication rate in a cohort of Israel Defense Force recruits enlisted in the calendar years 1991 to 1996 and to compare it with rates reported, in similar age groups, in large surveys during the 1960s. The overall complication rate was 0.4 per 10,000 vaccinees, and the rate of severe complications was very low, similar to previously published data. We conclude that among young healthy adults, vaccination with smallpox vaccine is relatively safe and is associated with a low rate of complications. Severe complications were very rare in this age group in our study. However, the complication rate is increasing with the increased percentage of primary vaccinees.  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