全文获取类型
收费全文 | 110篇 |
免费 | 21篇 |
国内免费 | 1篇 |
出版年
2021年 | 2篇 |
2019年 | 1篇 |
2018年 | 2篇 |
2017年 | 4篇 |
2015年 | 2篇 |
2014年 | 3篇 |
2013年 | 4篇 |
2012年 | 4篇 |
2011年 | 4篇 |
2010年 | 9篇 |
2009年 | 7篇 |
2008年 | 6篇 |
2007年 | 8篇 |
2006年 | 11篇 |
2005年 | 3篇 |
2004年 | 5篇 |
2003年 | 3篇 |
2002年 | 3篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1998年 | 5篇 |
1997年 | 3篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1994年 | 4篇 |
1992年 | 5篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 3篇 |
1980年 | 3篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1975年 | 1篇 |
1971年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有132条查询结果,搜索用时 15 毫秒
1.
Cleavage of a hydrophilic C-terminal domain increases growth-inhibitory activity of oncostatin M. 总被引:4,自引:1,他引:3
下载免费PDF全文
![点击此处可从《Molecular and cellular biology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Oncostatin M is a polypeptide cytokine, produced by normal and malignant hematopoietic cells, that has several in vitro activities, including the ability to inhibit growth of cultured carcinoma cells. Here we present a structural and functional comparison of two oncostatin M-related proteins (Mr 36,000 and 32,000) secreted by COS cells transfected with oncostatin M cDNA. The smaller of these forms lacked a hydrophilic C-terminal domain comprising predominantly basic amino acids. This domain was also absent from native oncostatin M produced by U937 cells. The 32,000-Mr form of oncostatin M was not produced by cells transfected with plasmids (G195 and G196) in which a potential trypsinlike cleavage site within the hydrophilic C-terminal domain was altered by site-directed mutagenesis. A 32,000-Mr fragment was produced by trypsin treatment of the 36,000-Mr form of oncostatin M. These observations suggest that the 32,000-Mr form of oncostatin M was derived from the 227-amino-acid propeptide by proteolytic cleavage at or near the paired basic residues at positions 195 and 196. Pro-oncostatin M was equally active in radioreceptor assays as the processed form but was 5- to 60-fold less active in growth inhibition assays. Likewise, nonprocessed mutant protein encoded by plasmid G196 was equally active in the radioreceptor assays as the processed form but was five- to ninefold less active in growth inhibition assays. Thus, the highly charged C-terminal domain of pro-oncostatin M is not required for receptor binding or growth-inhibitory activity but may alter the functional properties of the molecule. Propeptide processing of oncostatin M may be important for regulating in vivo activities of this cytokine. 相似文献
2.
Between 60% and 100% of epidermal growth factor (EGF) binding activity was recovered from membranes of the A431 human epidermoid carcinoma cell line treated with solutions containing the nonionic detergent Triton X-100. Approximately half of the recovered binding activity was sedimented at low centrifugal forece and hence was operationally insoluble in nonionic detergent solution. Receptors in both the detergent-soluble and -insoluble fractions displayed similar affinities for 125I-EGF, and the values were in good agreement with those obtained for receptors in untreated membranes. The receptors in both fractions also formed identical direct linkage complexes with 125I-EGF in similar yield, providing no evidence for partitioning of different molecular species of EGF receptors in the detergent-soluble and -insoluble fractions. Gel chromatography of the detergent-soluble membrane fraction on Sepharose 6-B revealed heterogeneity of 125I-EGF binding activity; the smallest and most monodisperse peak of activity resolved by this technique was eluted at a Stokes radius of 95 Å. Operationally soluble 125I-EGF binding activity also behaved heterogeneously during velocity sedimentation; more than half the activity sedimented more rapidly than the apparently monidisperse, 7S form. An average of less than half the nonionic detergent-solubilized activity recovered from 10 independent membrane preparations behaved as an apparently monodisperse entity. Since a maximum of 60% of 125I-EGF binding activity was operationally soluble, less than 25% of the total EGF binding activity was recovered in an apparently monodisperse form. The remaining 75% of the EGF receptors displayed a marked tendency to exist as aggregates in nonionic detergent solutions. 相似文献
3.
Identification of Proteins Secreted by Malaria Parasite into Erythrocyte using SVM and PSSM profiles
Ruchi Verma Ajit Tiwari Sukhwinder Kaur Grish C Varshney Gajendra PS Raghava 《BMC bioinformatics》2008,9(1):201
Background
Malaria parasite secretes various proteins in infected RBC for its growth and survival. Thus identification of these secretory proteins is important for developing vaccine/drug against malaria. The existing motif-based methods have got limited success due to lack of universal motif in all secretory proteins of malaria parasite. 相似文献4.
The signal produced by fluorescence in situ hybridization (FISH) often is inconsistent among cells and sensitivity is low. Small DNA targets on the chromatin are difficult to detect. We report here an improved nick translation procedure for Texas red and Alexa Fluor 488 direct labeling of FISH probes. Brighter probes can be obtained by adding excess DNA polymerase I. Using such probes, a 30 kb yeast transgene, and the rp1, rp3 and zein multigene clusters were clearly detected. 相似文献
5.
The signal produced by fluorescence in situ hybridization (FISH) often is inconsistent among cells and sensitivity is low. Small DNA targets on the chromatin are difficult to detect. We report here an improved nick translation procedure for Texas red and Alexa Fluor 488 direct labeling of FISH probes. Brighter probes can be obtained by adding excess DNA polymerase I. Using such probes, a 30?kb yeast transgene, and the rp1, rp3 and zein multigene clusters were clearly detected. 相似文献
6.
Uxmal and Tulum are two important Mayan sites in the Yucatan peninsula. The buildings are mainly composed of limestone and grey/black discoloration is seen on exposed walls and copious greenish biofilms on inner walls. The principal microorganisms detected on interior walls at both Uxmal and Tulum were cyanobacteria; heterotrophic bacteria and filamentous fungi were also present. A dark‐pigmented mitosporic fungus and Bacillus cereus, both isolated from Uxmal, were shown to be acidogenic in laboratory cultures. Cyanobacteria belonging to rock‐degrading genera Synechocystis and Gloeocapsa were identified at both sites. Surface analysis previously showed that calcium ions were present in the biofilms on buildings at Uxmal and Tulum, suggesting the deposition of biosolubilized stone. Apart from their potential to degrade the substrate, the coccoid cyanobacteria supply organic nutrients for bacteria and fungi, which can produce organic acids, further increasing stone degradation. 相似文献
7.
8.
Archibald SC Head JC Linsley JM Porter JR Robinson MK Shock A Warrellow GJ 《Bioorganic & medicinal chemistry letters》2000,10(9):993-995
Acyclic, disulphide derivatives of cysteine have been identified as moderately potent antagonists of alpha4beta1-mediated leukocyte cell adhesion to VCAM. This communication describes how they were discovered from a simple L-cystine derivative and using the structure-activity data of C*DThioPC* related cyclic peptides. 相似文献
9.
10.