全文获取类型
收费全文 | 653篇 |
免费 | 123篇 |
国内免费 | 17篇 |
出版年
2022年 | 6篇 |
2021年 | 8篇 |
2019年 | 7篇 |
2018年 | 13篇 |
2017年 | 7篇 |
2016年 | 18篇 |
2015年 | 22篇 |
2014年 | 31篇 |
2013年 | 21篇 |
2012年 | 39篇 |
2011年 | 38篇 |
2010年 | 22篇 |
2009年 | 29篇 |
2008年 | 25篇 |
2007年 | 27篇 |
2006年 | 20篇 |
2005年 | 31篇 |
2004年 | 26篇 |
2003年 | 25篇 |
2002年 | 20篇 |
2001年 | 24篇 |
2000年 | 31篇 |
1999年 | 13篇 |
1998年 | 11篇 |
1997年 | 7篇 |
1996年 | 12篇 |
1995年 | 9篇 |
1994年 | 14篇 |
1993年 | 10篇 |
1992年 | 10篇 |
1991年 | 12篇 |
1990年 | 7篇 |
1989年 | 14篇 |
1988年 | 6篇 |
1987年 | 12篇 |
1986年 | 14篇 |
1985年 | 13篇 |
1984年 | 13篇 |
1983年 | 10篇 |
1982年 | 10篇 |
1981年 | 5篇 |
1980年 | 7篇 |
1979年 | 6篇 |
1977年 | 11篇 |
1976年 | 8篇 |
1973年 | 5篇 |
1972年 | 5篇 |
1971年 | 5篇 |
1970年 | 5篇 |
1967年 | 5篇 |
排序方式: 共有793条查询结果,搜索用时 93 毫秒
141.
Kathryn B. Garber 《American journal of human genetics》2009,84(3):305-306
142.
Manuel Garber Michael C Zody Harindra M Arachchi Aaron Berlin Sante Gnerre Lisa M Green Niall Lennon Chad Nusbaum 《Genome biology》2009,10(6):R60-6
The most recent release of the finished human genome contains 260 euchromatic gaps (excluding chromosome Y). Recent work has
helped explain a large number of these unresolved regions as 'structural' in nature. Another class of gaps is likely to be
refractory to clone-based approaches, and cannot be approached in ways previously described. We present an approach for closing
these gaps using 454 sequencing. As a proof of principle, we closed all three remaining non-structural gaps in chromosome
15. 相似文献
143.
144.
Samuel D Vasikaran SA Paul Chubb Peter R Ebeling Nicole Jenkins Graham RD Jones Mark A Kotowicz Howard A Morris Hans-Gerhard Schneider Markus J Seibel Greg Ward 《The Clinical biochemist. Reviews / Australian Association of Clinical Biochemists》2014,35(4):237-242
Bone turnover markers (BTMs) are classified as either formation or resorption markers. Their concentrations in blood or urine of adults are considered to reflect the rate of bone remodelling and may be of use in the management of patients with bone disease. Major inter-method differences exist for BTMs, and harmonisation of methods is currently being pursued at an international level. Based on published data, this article describes age- and sex-specific Australian consensus reference intervals for adults for serum procollagen type I amino-terminal propeptide (s-PINP) and serum β-isomerised carboxy-terminal cross-linking telopeptide of type I collagen (s-CTX). 相似文献
145.
报道了内蒙古清水河黄土丘陵地区发现的紫萼藓科1新变种——缨齿藓菱形变种[Jaffueliobryum wrightii(Sull.)Thér.var.rhombicumX.L.BaiSarula],该变种与干旱山地岩面生境中的原变种缨齿藓[Jaffueliobryum wrightii(Sull.)Thér.]相似,生境的变化导致其形态发生变化,主要表现在上部细胞菱形和细胞壁背部强烈加厚,未分化的叶上部边缘细胞、中肋横切面细胞不分化,叶片长0.7~0.8mm,毛尖长0.8~1.3mm。文中对缨齿藓及其新变种的形态学特征,分布和生境进行了描述,并提供了显微照片,另外,列出了缨齿藓属5个种的检索表。 相似文献
146.
Emily M. Mallick John J. Garber Vijay K. Vanguri Sowmya Balasubramanian Timothy Blood Stacie Clark Didier Vingadassalom Christopher Louissaint Beth McCormick Scott B. Snapper John M. Leong 《Cellular microbiology》2014,16(9):1405-1424
Enterohaemorrhagic Escherichia coli (EHEC) colonizes the intestine and causes bloody diarrhoea and kidney failure by producing Shiga toxin. Upon binding intestinal cells, EHEC triggers a change in host cell shape, generating actin ‘pedestals’ beneath bound bacteria. To investigate the importance of pedestal formation to disease, we infected genetically engineered mice incapable of supporting pedestal formation by an EHEC‐like mouse pathogen, or wild type mice with a mutant of that pathogen incapable of generating pedestals. We found that pedestal formation promotes attachment of bacteria to the intestinal mucosa and vastly increases the severity of Shiga toxin‐mediated disease. 相似文献
147.
Purpose
In addition to excess adiposity, low cardiorespiratory fitness (CRF) and low musculoskeletal fitness (MSF) are important independent risk factors for future cardio-metabolic disease in adolescents, yet global fitness surveillance in adolescents is poor. The objective of this study was to describe and investigate geographical variation in levels of health-related physical fitness, including CRF, MSF, body mass index (BMI), and waist circumference (WC) in Chilean 8th graders.Methods
This cross-sectional study was based on a population-based, representative sample of 19,929 8th graders (median age = 14 years) in the 2011 National Physical Education Survey from Chile. CRF was assessed with the 20-meter shuttle run test, MSF with standing broad jump, and body composition with BMI and WC. Data were classified according to health-related standards. Prevalence of levels of health-related physical fitness was mapped for each of the four variables, and geographical variation was explored at the country level by region and in the Santiago Metropolitan Area by municipality.Results
Girls had significantly higher prevalence of unhealthy CRF, MSF, and BMI than boys (p<0.05). Overall, 26% of boys and 55% of girls had unhealthy CRF, 29% of boys and 35% of girls had unhealthy MSF, 29% of boys and 44% of girls had unhealthy BMI, and 31% of adolescents had unhealthy WC. High prevalence of unhealthy fitness levels concentrates in the northern and middle regions of the country and in the North and Southwest sectors for the Santiago Metropolitan Area.Conclusion
Prevalence of unhealthy CRF, MSF, and BMI is relatively high among Chilean 8th graders, especially in girls, when compared with global estimates. Identification of geographical regions and municipalities with high prevalence of unhealthy physical fitness presents opportunity for targeted intervention. 相似文献148.
目的研究长爪沙鼠发情周期,揭示发情规律,优化判定方法。方法连续18 d采集50只长爪沙鼠阴道上皮脱落细胞涂片,采用角化细胞计数法研究长爪沙鼠发情周期规律。比较瑞氏染色、HE染色和直接镜检判定发情周期4个时相的优缺点。结果长爪沙鼠的发情周期有稳定型、不稳定型、假孕三种类型。其中稳定型占68.6%,发情周期为(106.3±35.0)h,可分为4个时相。4个时相角化细胞的比例分别为发情前期(13.5±7.8)%、发情期(86.7±9.9)%、发情后期(27.9±12.8)%和发情间期(3.3±2.8)%。结论角化细胞计数能准确地判定长爪沙鼠的发情周期及各个时相。直接镜检法能快速反映阴道脱落细胞的形态。 相似文献
149.
人TRAIL基因cDNA的克隆及其在COS—7细胞中的表达 总被引:1,自引:0,他引:1
TRAIL(TNFrelatedapoptosisinducingligand)是最近克隆的肿瘤坏死因子(TNF)家族的新成员,由于它的蛋白质结构和生物学效应类似于FAS/APO1L,因此,也被称为APO2L。在低浓度下,TRAIL能迅速地诱导多种肿瘤细胞系的?.. 相似文献
150.