全文获取类型
收费全文 | 171篇 |
免费 | 16篇 |
国内免费 | 43篇 |
出版年
2024年 | 2篇 |
2023年 | 1篇 |
2022年 | 4篇 |
2021年 | 8篇 |
2020年 | 4篇 |
2019年 | 3篇 |
2018年 | 2篇 |
2017年 | 6篇 |
2016年 | 8篇 |
2015年 | 5篇 |
2014年 | 14篇 |
2013年 | 12篇 |
2012年 | 10篇 |
2011年 | 21篇 |
2010年 | 10篇 |
2009年 | 13篇 |
2008年 | 12篇 |
2007年 | 10篇 |
2006年 | 11篇 |
2005年 | 9篇 |
2004年 | 8篇 |
2003年 | 7篇 |
2002年 | 8篇 |
2001年 | 3篇 |
2000年 | 4篇 |
1999年 | 4篇 |
1998年 | 5篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1993年 | 1篇 |
1990年 | 2篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1984年 | 1篇 |
1983年 | 3篇 |
1982年 | 1篇 |
1980年 | 1篇 |
1978年 | 3篇 |
1976年 | 3篇 |
1975年 | 2篇 |
排序方式: 共有230条查询结果,搜索用时 15 毫秒
51.
流式细胞术研究细胞凋亡的方法与技术 总被引:1,自引:0,他引:1
细胞发生凋亡时,会伴随着一系列形态学、生物化学及分子生物学性质的变化,包括细胞皱缩,核染色质凝聚,细胞膜通透性改变,Caspases激活,线粒体跨膜电位降低,膜磷酯酰丝氨酸外化,胞质Ca2+浓度升高,DNA片段化及含量变化等特点.应用流式细胞术进行细胞凋亡的研究,对于探讨胚胎发育、衰老以及研究肿瘤的发生、发展和转化等病理生理过程和病毒感染及免疫等具有十分重要的意义.本文就细胞凋亡的特征、基于细胞膜功能的流式细胞术检测方法和基于细胞器功能的流式细胞术检测方法等关键性问题进行了阐述. 相似文献
52.
圆瓣姜花根茎挥发油的化学成分 总被引:1,自引:0,他引:1
纳智 《热带亚热带植物学报》2006,14(5):417-420
利用水蒸汽蒸馏法提取圆瓣姜花根茎挥发油,运用毛细管气相色谱-质谱联用法对挥发油进行了分析,分离出60个峰,鉴定了其中的51种成分,所鉴定成分占挥发油总量的97.32%,其主要化学成分为单萜及倍半萜类化合物。 相似文献
53.
大鼠子宫内膜异位模型的建立与组织学观察 总被引:8,自引:1,他引:7
目的为开发诊治子宫内膜异位症(endometriosis,EMT)的新药研究提供理想的动物模型。方法取雌性未交配性成熟大鼠,术前雌激素诱导,麻醉开腹取部份右侧子宫,将内膜种植于左腹壁内,术后16周取出包块,进行组织形态学、组织化学观察。结果异位内膜在腹壁内生长,呈隆起囊状小包块,内有黏液,具有正常子宫内膜基本组织结构,囊腔较大。异位内膜中有糖原、RNA的存在。结论该手术方法建立的子宫异位内膜生长良好,术后一周就可摸及包块大小,为开发研究子宫内膜异位症的新药提供了方便。 相似文献
54.
HELÉNA RAGONÉ 《American anthropologist》2004,106(1):176-177
Experiencing the New Genetics: Family and Kinship on the Medical Frontier. Kaja Finkler. Philadelphia: University of Pennsylvania Press, 2000. 296 pp.
Born and Bred: Idioms and New Reproductive Technologies in England. Jeanette Edwards. New York: Oxford University Press, 2000. 264 pp. 相似文献
Born and Bred: Idioms and New Reproductive Technologies in England. Jeanette Edwards. New York: Oxford University Press, 2000. 264 pp. 相似文献
55.
56.
Gene and domain duplication in the chordate Otx gene family: insights from amphioxus Otx 总被引:6,自引:1,他引:5
We report the genomic organization and deduced protein sequence of a
cephalochordate member of the Otx homeobox gene family (AmphiOtx) and show
its probable single-copy state in the genome. We also present molecular
phylogenetic analysis indicating that there was single ancestral Otx gene
in the first chordates which was duplicated in the vertebrate lineage after
it had split from the lineage leading to the cephalochordates. Duplication
of a C-terminal protein domain has occurred specifically in the vertebrate
lineage, strengthening the case for a single Otx gene in an ancestral
chordate whose gene structure has been retained in an extant
cephalochordate. Comparative analysis of protein sequences and published
gene expression patterns suggest that the ancestral chordate Otx gene had
roles in patterning the anterior mesendoderm and central nervous system.
These roles were elaborated following Otx gene duplication in vertebrates,
accompanied by regulatory and structural divergence, particularly of Otx1
descendant genes.
相似文献
57.
58.
59.
Rosellinia desmazieresii was found for the first time on a tree of Scots pine. It occurred on a dying tree in a mixed Scots pine-oak plantation in Poland. The fungus girdled the base of the trunk, where perithecia were produced abundantly. The fungus was evidently the cause of the tree's poor growth and ultimate death. 相似文献
60.
Cousens C Bishop JV Philbey AW Gill CA Palmarini M Carlson JO DeMartini JC Sharp JM 《Journal of virology》2004,78(16):8506-8512
Ovine pulmonary adenocarcinoma (OPA) is an infectious lung tumor of sheep caused by Jaagsiekte sheep retrovirus (JSRV). To test the hypothesis that JSRV insertional mutagenesis is involved in the oncogenesis of OPA, we cloned and characterized 70 independent integration sites from 23 cases of OPA. Multiple integration sites were identified in most tumors. BLAST analysis of the sequences did not disclose any potential oncogenic motifs or any identical integration sites in different tumors. Thirty-seven of the integration sites were mapped to individual chromosomes by PCR with a panel of sheep-hamster hybrid cell lines. Integration sites were found on 20 of the 28 sheep chromosomes, suggesting a random distribution. However, four integration sites from four different tumors mapped to chromosome 16. By Southern blot hybridization, probes derived from two of these sites mapped to within 5 kb of each other on normal sheep DNA. These sites were found within a single sheep bacterial artificial chromosome clone and were further mapped to only 2.5 kb apart, within an uncharacterized predicted gene and less than 200 kb from a mitogen-activated protein kinase-encoding gene. These findings suggest that there is at least one common integration site for JSRV in OPA and add weight to the hypothesis that insertional mutagenesis is involved in the development of this tumor. 相似文献