全文获取类型
收费全文 | 5252篇 |
免费 | 394篇 |
国内免费 | 268篇 |
专业分类
5914篇 |
出版年
2024年 | 8篇 |
2023年 | 75篇 |
2022年 | 126篇 |
2021年 | 236篇 |
2020年 | 179篇 |
2019年 | 216篇 |
2018年 | 196篇 |
2017年 | 176篇 |
2016年 | 282篇 |
2015年 | 321篇 |
2014年 | 358篇 |
2013年 | 417篇 |
2012年 | 480篇 |
2011年 | 425篇 |
2010年 | 251篇 |
2009年 | 204篇 |
2008年 | 282篇 |
2007年 | 227篇 |
2006年 | 194篇 |
2005年 | 173篇 |
2004年 | 184篇 |
2003年 | 132篇 |
2002年 | 141篇 |
2001年 | 82篇 |
2000年 | 48篇 |
1999年 | 73篇 |
1998年 | 48篇 |
1997年 | 54篇 |
1996年 | 38篇 |
1995年 | 29篇 |
1994年 | 32篇 |
1993年 | 21篇 |
1992年 | 33篇 |
1991年 | 12篇 |
1990年 | 13篇 |
1989年 | 15篇 |
1988年 | 15篇 |
1987年 | 13篇 |
1986年 | 10篇 |
1985年 | 11篇 |
1984年 | 12篇 |
1983年 | 19篇 |
1980年 | 5篇 |
1979年 | 6篇 |
1978年 | 5篇 |
1977年 | 5篇 |
1975年 | 6篇 |
1974年 | 5篇 |
1973年 | 6篇 |
1970年 | 3篇 |
排序方式: 共有5914条查询结果,搜索用时 0 毫秒
101.
本研究对葡萄(Vitis vinifera L.)的Golden2-like (GLK)转录因子家族进行了全基因组鉴定和表达模式分析,并利用品种‘玫瑰香’(V.vinifera cv.Muscat Hamburg)进一步验证其在低温胁迫下的响应。结果显示,葡萄Golden2-like家族共46个成员,分为5个亚族,同一亚族的保守结构域相似。46个VvGLK分别定位于细胞核、叶绿体、细胞质和过氧化物酶体中,其启动子区域含多种逆境应答顺式作用元件。基因芯片分析结果表明,22个Golden2-like基因在果实发育过程中变化显著。同时,有15、15和9个基因分别响应盐、干旱和低温胁迫。qRT-PCR分析发现26个基因参与低温应答。VvGLK41在所有胁迫处理中均下调表达。 相似文献
102.
103.
Wan Yun Ho Jer-Cherng Chang Kenneth Lim Amaury Cazenave-Gassiot Aivi T. Nguyen Juat Chin Foo Sneha Muralidharan Ashley Viera-Ortiz Sarah J.M. Ong Jin Hui Hor Ira Agrawal Shawn Hoon Olubankole Aladesuyi Arogundade Maria J. Rodriguez Su Min Lim Seung Hyun Kim John Ravits Shi-Yan Ng Markus R. Wenk Edward B. Lee Greg Tucker-Kellogg Shuo-Chien Ling 《The Journal of cell biology》2021,220(9)
104.
References: 《生物数学学报》1998,13(4):435-438
IIntroductionIn1993,KuangY[11gavetheopenp毗fern9.2:恤tainsufficientCOnditionsfortheeds-tenceofpO8ltlvependIc劝utionsinN”(t)=N(t)[a(t)一B(t)N()一b(t)N(t—r(t))-c(t)N”(t一巾》】(1)wherea(t),尸(t),b(t),c(t),,(t)are。"negativecontinuouspo。odlcfunctionswithpenodT.Inthispaper,weconsideraspecialcasewheng(t)。0,b(t)>0,c(t)。c,r(t)。,,i.e.O鹏idertheexlstenceOfp用tlvependicdutionsOftkforirlBynsf叩ofsomenewtechnicsandtoPOloglcaldeg… 相似文献
105.
Liangming Chen Zhigang Zhao Xi Liu Linglong Liu Ling Jiang Shijia Liu Wenwei Zhang Yihua Wang Yuqiang Liu Jianmin Wan 《Molecular breeding : new strategies in plant improvement》2011,27(2):247-258
The incomplete fertility of japonica × indica rice hybrids has inhibited breeders’ access to the substantial heterotic potential of these hybrids. As hybrid sterility
is caused by an allelic interaction at a small number of loci, it is possible to overcome it by simple introgression at the
major sterility loci. Here we report the use of marker-assisted backcrossing to transfer into the elite japonica cv. Zhendao88 a photoperiod-sensitive male sterility gene from cv. Lunhui422S (indica) and the yellow leaf gene from line Yellow249 (indica). The microsatellite markers RM276, RM455, RM141 and RM185 were used to tag the fertility genes S5, S8, S7 and S9, respectively. Line 509S is a true-breeding photoperiod-sensitive male sterile plant, which morphologically closely resembles
the japonica type. Genotypic analysis showed that the genome of line 509S comprises about 92% japonica DNA. Nevertheless, hybrids between line 509S and japonica varieties suffer from a level of hybrid sterility, although the line is highly cross-compatible with indica types, with the resulting hybrids expressing a significant degree of heterosis. Together, these results suggest that segment
substitution on fertility loci based on known information and marker-assisted selection are an effective approach for utilizing
the heterosis of rice inter-subspecies. 相似文献
106.
107.
Fei Yao Pramila N. Ariyaratne Axel M. Hillmer Wah Heng Lee Guoliang Li Audrey S. M. Teo Xing Yi Woo Zhenshui Zhang Jieqi P. Chen Wan Ting Poh Kelson F. B. Zawack Chee Seng Chan See Ting Leong Say Chuan Neo Poh Sum D. Choi Song Gao Niranjan Nagarajan Hervé Thoreau Atif Shahab Xiaoan Ruan Valère Cacheux-Rataboul Chia-Lin Wei Guillaume Bourque Wing-Kin Sung Edison T. Liu Yijun Ruan 《PloS one》2012,7(9)
Structural variations (SVs) contribute significantly to the variability of the human genome and extensive genomic rearrangements are a hallmark of cancer. While genomic DNA paired-end-tag (DNA-PET) sequencing is an attractive approach to identify genomic SVs, the current application of PET sequencing with short insert size DNA can be insufficient for the comprehensive mapping of SVs in low complexity and repeat-rich genomic regions. We employed a recently developed procedure to generate PET sequencing data using large DNA inserts of 10–20 kb and compared their characteristics with short insert (1 kb) libraries for their ability to identify SVs. Our results suggest that although short insert libraries bear an advantage in identifying small deletions, they do not provide significantly better breakpoint resolution. In contrast, large inserts are superior to short inserts in providing higher physical genome coverage for the same sequencing cost and achieve greater sensitivity, in practice, for the identification of several classes of SVs, such as copy number neutral and complex events. Furthermore, our results confirm that large insert libraries allow for the identification of SVs within repetitive sequences, which cannot be spanned by short inserts. This provides a key advantage in studying rearrangements in cancer, and we show how it can be used in a fusion-point-guided-concatenation algorithm to study focally amplified regions in cancer. 相似文献
108.
109.
110.
The psychrophile Clostridium sp. strain 69 contains a thermolabile triose phosphate isomerase which is inactivated rapidly in vitro and in vivo at 32 C. 相似文献