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111.
蛇毒C-型凝集素研究进展 总被引:5,自引:2,他引:5
蛇毒中含有丰富的非酶活性C-型凝集素蛋白,根据其结构及功能的差异,该类蛋白可分为Ca^2 依赖的有糖基识别活性的C-型真凝集素及无糖基识别活性的C-型凝集素样蛋白。C-型真凝集素的结构相似度高,而功能却较为单一,具有特异性糖结合活性;C-型凝集样蛋白的结构变异度大,活性亦具有多样性。后者能通过特异性的蛋白质-蛋白质相互作用而作用于血液凝固系统及血小板,从而发挥抗凝或促凝的生理功能。 相似文献
112.
利用K型、D型和W型三种不育胞质与三个保持系培育成的9个(三套)同质异核或同核异质不育系,以其与5个恢复系按p×q交配模式设计,研究三种不育胞质对F1粒长、粒宽、千粒重和长/宽等谷粒性状的遗传效应.结果表明:各性状均以不育胞质一般配合力效应最重要,随性状而异,还有与保持系、恢复系及二者的一、二级特殊配合力效应;三种不育胞质各性状的一般配合力效应均表现显著或极显著差异,K胞质在千粒重方面、D胞质在粒长和长/宽方面、W胞质在粒宽方面有加性促进作用.因此,注意选择不育胞质源和对质核组合的评价,可进一步改良杂交水稻谷粒性状. 相似文献
113.
九种蹄盖蕨科植物配子体的酯酶同工酶分析 总被引:4,自引:1,他引:4
本文培养了蹄盖蕨科9个种即中华蹄盖蕨(Athyriumsinense)带岭蹄盖蕨(A.dalingense)、多齿蹄盖蕨(A.multidentatum)(包括青柄和紫柄2种带岭蹄蕨类型)、东北蛾眉蕨(Lunathyriumpycnosorum)、朝鲜介蕨(Dryoathyriumcoreanum)、山冷蕨(Cystopterissudetica)、假冷蕨(Pseudocystopterisspinulosa)、欧洲羽节蕨(Gymnocarpiumdryopteris)和黑鳞短肠蕨(Alantodiacrenata)的配子体为材料,进行酯酶同工酶的分析,以表明它们的种间差异,其中多齿蹄盖蕨的青柄和紫柄两种类型的酶谱存在明显差异,应考虑紫柄为多齿蹄盖蕨的变型。 相似文献
114.
Wen‐Yuan Xie Fen‐Yao Zhang Zheng‐Hai Chen Gen‐You Li Guo‐Hua Xia 《Nordic Journal of Botany》2013,31(4):414-418
Ostericum atropurpureum G. Y. Li, G. H. Xia & W. Y. Xie (Apiaceae, Apioideae) from Zhejiang, China, is described and illustrated. It is closely related to O. huadongense Z. H. Pan & X. H. Li and O. sieboldii (Miquel) Nakai, but differs in having leaves with 1.5–9.0 cm long petiole, linear bracteoles 6–12 mm long, 5–9 rays, 7–14‐flowered umbellules, dark purple petals, broadly winged dorsal and lateral fruit ribs, 1.0–1.5 mm broad, 3–6 vittae in each furrow and 4–8 on the commissure. 相似文献
115.
Wei Chen Wen Shu Min Wang Yongchun Hou Yinyin Xia Weiguo Xu Liqiong Bai Shaofa Nie Shiming Cheng Yihua Xu 《PloS one》2013,8(3)
The incidence of tuberculosis (TB) and its risk factors in China remains unclear. This study examined TB incidence and relative risk factors in rural areas of China. Participants (n = 177,529) were recruited in Xiangtan County (in the central area of China) and in Danyang County (in the eastern area of China) in 2009 and a followed-up study was conducted for one year. The incidence density of pulmonary TB and smear-positive TB were 91.6 (95% CI: 78.7, 106.0) per 100,000 person-year and 36.7 (95% CI: 33.1, 52.4) per 100,000 person-year respectively in Xiangtan, and 47.3 (95% CI: 38.2, 57.5) per 100,000 person-year and 22.7 (95% CI: 16.5, 30.8) per 100,000 person-year in Danyang. The medical history of TB was associated with TB, with the relative risk (RR) of 7.00 (95% CI: 2.76, 17.18) in Xiangtan and that of 31.08 (95% CI: 13.22, 73.10) in Danyang. The association between TB and per capita living space over median was found in Xiangtan, with the RR of 1.86 (95% CI: 1.15, 3.01). No association was found between TB and the insurance status, the contact history with TB, the history of diabetes, smoking, or per capita annual income. The host genetic susceptibility, and social factors such as education and income could be considered in future studies. 相似文献
116.
Zhou Xin Yang Zhi-Bo Han Yue Ru Ji You Wei Wang Lu Liang Ying Chi Shao Guang Yang Li Na Li Wei Feng Luo Jian Ping Li Dan Dan Chen Wen Jing Du Xiao Cang Cao Guang Sheng Zhuo Tao Wang Zhong Chao Han 《PloS one》2013,8(3)
Mesenchymal stem cells (MSCs) reside in almost all of the body tissues, where they undergo self-renewal and multi-lineage differentiation. MSCs derived from different tissues share many similarities but also show some differences in term of biological properties. We aim to search for significant differences among various sources of MSCs and to explore their implications in physiopathology and clinical translation. We compared the phenotype and biological properties among different MSCs isolated from human term placental chorionic villi (CV), umbilical cord (UC), adult bone marrow (BM) and adipose (AD). We found that CD106 (VCAM-1) was expressed highest on the CV-MSCs, moderately on BM-MSCs, lightly on UC-MSCs and absent on AD-MSCs. CV-MSCs also showed unique immune-associated gene expression and immunomodulation. We thus separated CD106+cells and CD106−cells from CV-MSCs and compared their biological activities. Both two subpopulations were capable of osteogenic and adipogenic differentiation while CD106+CV-MSCs were more effective to modulate T helper subsets but possessed decreased colony formation capacity. In addition, CD106+CV-MSCs expressed more cytokines than CD106−CV-MSCs. These data demonstrate that CD106 identifies a subpopulation of CV-MSCs with unique immunoregulatory activity and reveal a previously unrecognized mechanism underlying immunomodulation of MSCs. 相似文献
117.
人白细胞介素18(IL-18)是新近发现的细胞因子之一.研究表明它参与T1辅助细胞介导的细胞免疫.利用RT-PCR技术从人外周血细胞扩增得到了IL-18的cDNA并测定其核酸序列.利用基因重组技术构建IL-18的表达载体,并在大肠杆菌中进行了表达.这为以后进一步研究IL-18的功能奠定了基础. 相似文献
118.
用聚丙烯酰胺凝胶电泳和紫外光谱法分析非冬眠期喜马拉雅土拨鼠4种组织的乳酸脱氢酶(LDH)同工酶的酶谱及其活力,该鼠骨骼肌酶带的多态分布,可能是潜在的调节基因调控所致。另外,本文还对构象异构体产生的亚带进行了研讨。 相似文献
119.
120.
Olivier Maurin Artemis Anest Sidonie Bellot Edward Biffin Grace Brewer Tristan Charles-Dominique Robyn S. Cowan Steven Dodsworth Niroshini Epitawalage Berta Gallego Augusto Giaretta Renato Goldenberg Deise J.P. Gonçalves Shirley Graham Peter Hoch Fiorella Mazine Yee Wen Low Catherine McGinnie Fabián A. Michelangeli Sarah Morris Darin S. Penneys Oscar Alejandro Pérez Escobar Yohan Pillon Lisa Pokorny Gustavo Shimizu Vanessa G. Staggemeier Andrew H. Thornhill Kyle W. Tomlinson Ian M. Turner Thais Vasconcelos Peter G. Wilson Alexandre R. Zuntini William J. Baker Félix Forest Eve Lucas 《American journal of botany》2021,108(7):1087-1111