全文获取类型
收费全文 | 1040篇 |
免费 | 56篇 |
国内免费 | 595篇 |
出版年
2024年 | 3篇 |
2023年 | 17篇 |
2022年 | 51篇 |
2021年 | 28篇 |
2020年 | 34篇 |
2019年 | 56篇 |
2018年 | 37篇 |
2017年 | 81篇 |
2016年 | 75篇 |
2015年 | 66篇 |
2014年 | 64篇 |
2013年 | 38篇 |
2012年 | 74篇 |
2011年 | 68篇 |
2010年 | 76篇 |
2009年 | 62篇 |
2008年 | 64篇 |
2007年 | 62篇 |
2006年 | 54篇 |
2005年 | 30篇 |
2004年 | 43篇 |
2003年 | 32篇 |
2002年 | 21篇 |
2001年 | 39篇 |
2000年 | 55篇 |
1999年 | 67篇 |
1998年 | 31篇 |
1997年 | 39篇 |
1996年 | 31篇 |
1995年 | 34篇 |
1994年 | 35篇 |
1993年 | 21篇 |
1992年 | 19篇 |
1991年 | 12篇 |
1990年 | 10篇 |
1989年 | 27篇 |
1988年 | 10篇 |
1987年 | 6篇 |
1986年 | 7篇 |
1985年 | 8篇 |
1983年 | 48篇 |
1982年 | 6篇 |
1981年 | 8篇 |
1980年 | 6篇 |
1979年 | 3篇 |
1978年 | 3篇 |
1975年 | 3篇 |
1966年 | 3篇 |
1965年 | 4篇 |
1964年 | 3篇 |
排序方式: 共有1691条查询结果,搜索用时 15 毫秒
101.
<正>背景:使用23价肺炎球菌多糖疫苗(PPV23)的好处是有争议的。作者研究了PPV23在年龄大于等于60岁人群中预防社区获得性肺炎(CAP)的临床效果。方法 :研究是在西班牙的塔拉戈纳地区,从2008年11月1日到2011年12月30日,年龄≥60岁人群中选取27 204人作为队列研究的人群基础。主要结果来自肺炎球菌CAP(有菌血症和非菌血 相似文献
102.
De Rossi A Zanchetta M Vitone F Antonelli G Bagnarelli P Buonaguro L Capobianchi MR Clementi M Abbate I Canducci F Monachetti A Riva E Rozera G Scagnolari C Tagliamonte M Re MC;SIVIM 《The new microbiologica》2010,33(4):293-302
Despite the widespread use of molecular biology techniques, standardized methods for the measurement of HIV-1 proviral DNA are currently lacking and several discordant results are still present in different studies. To assess the clinical meaning of the proviral DNA load, a study group comprising seven different laboratories was set up to standardize a HIV-1 proviral DNA quantification method able to assess the DNA proviral load of the most relevant circulating HIV-1 subtypes. Reference samples (24 cellular samples infected with HIV-1 clade B, and 40 samples of peripheral blood mononuclear cells containing different concentrations of plasmids expressing different HIV-1 clades) were distributed and tested blindly. All laboratories employed hTERT gene as housekeeping gene and primers within the gag gene to quantify different HIV-1 clades. Inter-laboratory results did not differ statistically but showed only minor variations concerning HIV-1 DNA amounts and different HIV clades, with a good agreement among the laboratories participating in the study. Since test standardization represents a key step for future application in clinical practice, further studies of the patients' samples are in progress to establish the real meaning and utility of the proviral DNA load for clinical management of HIV-1 infected patients. 相似文献
103.
作为保证销售额的支柱产品免疫制剂的专利到期,Astellas公司需要新产品。为了强化新药研究,扩大了在筑波市的研究中心并在其中设立了新的研究所。通过合作在公司外部培育新技术和新药的种子,然后择机引入公司生产。 相似文献
104.
105.
Genetic analysis of fluvastatin response and dyslipidemia in renal transplant recipients 总被引:1,自引:0,他引:1
Singer JB Holdaas H Jardine AG Fellstrøm B Os I Bermann G Meyer JM;Assessment of Lescol in Renal Transplantation 《Journal of lipid research》2007,48(9):2072-2078
The Assessment of Lescol in Renal Transplantation clinical trial demonstrated the efficacy of fluvastatin in reducing cardiovascular (CV) disease in renal transplant recipients. The study included a voluntary pharmacogenetic component, enrolling 1,404 patients, which allowed association testing of baseline measures and longitudinal analysis of the 707 fluvastatin-treated and 697 placebo-treated individuals. A candidate gene approach, examining 42 polymorphisms in 18 genes, was used to test for association between selected polymorphisms and major adverse cardiac events, graft failure, change in LDL and HDL cholesterol, and baseline LDL and HDL cholesterol. Reported associations between cholesteryl ester transfer protein (CETP) and baseline HDL cholesterol were replicated, with four previously implicated single nucleotide polymorphisms significantly associated in males and one in females; tests of reported associations between CETP and CV disease yielded varying results. We found no evidence for genetic factors affecting fluvastatin response. Polymorphisms in 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) previously reported to affect the efficacy of pravastatin did not show a similar effect on the reduction of LDL cholesterol by fluvastatin. 相似文献
106.
c-mos基因在动物卵母细胞减数分裂调控中起作用,但其作用机制目前仍不清楚。本实验通过RT-PCR、免疫荧光激光共聚焦检测方法检测了猪卵母细胞在体外成熟培养过程中c-mos基因在转录水平、翻译水平上的表达以及蛋白的分布,并应用注射小干扰RNA(siRNA)方法对其进行了RNA干扰(RNAi)研究。结果显示,猪卵母细胞在体外成熟培养过程中c-mos基因mRNA量逐渐增高,电激活后6h接近完全降解;MOS(c-mos基因蛋白产物)在GV卵母细胞生发泡中有一定量的表达,生发泡破裂(GVBD)前表达量增加且开始向卵母细胞胞质弥散,成熟培养44h未成熟卵母细胞中的MOS表达量要高于成熟卵母细胞,激活后6h核区MOS明显减少,但仍然有少量MOS分布于胞质中;成熟培养前干扰c-mos基因,所用三个siRNA都能成功敲低mRNA量,分别是同时期对照组mRNA量的0.08±0.03,0.11±0.06和0.20±0.06倍,干扰后虽然没有完全剔除MOS,但MOS量比同期卵母细胞有明显下降,仍可以引发成熟卵母细胞染色体解凝集。研究结果揭示了猪卵母细胞体外成熟及发育进程中c-mos基因在转录和翻译水平上的动态表达规律,建立了猪卵母细胞c-mos基因RNAi体系,为MOS在猪卵母细胞发育过程中的功能研究建立了重要的基础。 相似文献
107.
Admixture mapping of an allele affecting interleukin 6 soluble receptor and interleukin 6 levels
下载免费PDF全文
![点击此处可从《American journal of human genetics》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Reich D Patterson N Ramesh V De Jager PL McDonald GJ Tandon A Choy E Hu D Tamraz B Pawlikowska L Wassel-Fyr C Huntsman S Waliszewska A Rossin E Li R Garcia M Reiner A Ferrell R Cummings S Kwok PY Harris T Zmuda JM Ziv E;Health Aging Body Composition 《American journal of human genetics》2007,80(4):716-726
Circulating levels of inflammatory markers can predict cardiovascular disease risk. To identify genes influencing the levels of these markers, we genotyped 1,343 single-nucleotide polymorphisms (SNPs) in 1,184 African Americans from the Health, Aging and Body Composition (Health ABC) Study. Using admixture mapping, we found a significant association of interleukin 6 soluble receptor (IL-6 SR) with European ancestry on chromosome 1 (LOD 4.59), in a region that includes the gene for this receptor (IL-6R). Genotyping 19 SNPs showed that the effect is largely explained by an allele at 4% frequency in West Africans and at 35% frequency in European Americans, first described as associated with IL-6 SR in a Japanese cohort. We replicate this association (P<1.0x10-12) and also demonstrate a new association with circulating levels of a different molecule, IL-6 (P<3.4x10-5). After replication in 1,674 European Americans from Health ABC, the combined result is even more significant: P<1.0x10-12 for IL-6 SR, and P<2.0x10-9 for IL-6. These results also serve as an important proof of principle, showing that admixture mapping can not only coarsely localize but can also fine map a phenotypically important variant. 相似文献
108.
109.
Xue-mei ZHANG Yan-chun CHE Jing-jing WANG Long-ding LIU Ming-xue XIE Qi-han LI 《Virologica Sinica》2007,22(1):41-45
The genome of a new SV40 strain (SV-IMB) isolated from a rhesus monkey was completely sequenced and compared with other isolates. The results showed that the whole genome contains 5246bp, and the average identity of SV-IMB was 98.1% as compared to other SV40 isolates. Its regulatory region is composed of a complete enhancer and a defective enhancer. Amino acid changes occurred to some extent in both the large T antigen (T-Ag) and VP1 region. The findings demonstrate that the SV-IMB is a new SV40 isolate. 相似文献
110.
Insect viruses are attractive as biological control agents and could be a feasible alternative to chemical insecticides in the management of insect infestations. This review describes recent advances in the development of wild-type and genetically modified viruses as insecticides. A new strategy of application of insect viruses in China is reviewed. Also, the assessment of biosafety of genetically modified Helicoverpa armigera Nucleopolyhedovirus (HearNPV) is emphasized as a case-study. 相似文献