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1.
将对结素和破类呈现阳性皮肤延迟超敏反应的恒河猴的淋巴结和脾脏剪碎,匀浆,过滤和高速离心,以葡聚糖G25凝胶过滤分离成6个组分。只有组分Ⅳ不仅能将皮肤延迟超敏反应在同种异体之间转移,而且能从恒河猴转移到人。不管TF供体和培养淋巴细胞供体对抗原的应答如何,所有组分均有增强SK—SD刺激淋巴细胞转化作用,组分Ⅲ和Ⅳ的混合物作用最强。组分Ⅲ和Ⅳ对人的淋巴细胞亦有类似的作用。因此,恒河猴TF增强抗原刺激淋巴细胞转化的作用是没有抗原特异性和种属特异性的。 初步的生化分析表明,组分Ⅳ含有RNA,多肽和次黄嘌呤,薄层色谱有2个254nm紫外光吸收成分和2个节三酮显色成分,等电点聚焦电泳时出现17条考马斯兰R250着色带。 这些结果说明,有可能用恒河猴制备某些人类疾病的特异性TF。 相似文献
2.
水稻无花药型不育材料的发现及其转育后代育性初步观察 总被引:4,自引:0,他引:4
水稻无花药型不育材料的发现及其转育后代育性初步观察①1宋德明1王志2刘永胜1王茂理1龙太康2孙敬三1(四川省绵阳市农业科学研究所绵阳621002)2(中国科学院植物研究所北京100093)关键词水稻,野生稻,无花药细胞质雄性不育DEVELOPMENT... 相似文献
3.
Wang F Liu P Zhang Q Zhu J Chen T Arimura SI Tsutsumi N Lin J 《The Plant journal : for cell and molecular biology》2012,72(1):43-56
The balance between mitochondrial fission and fusion is disrupted during mitosis, but the mechanism governing this phenomenon in plant cells remains enigmatic. Here, we used mitochondrial matrix‐localized Kaede protein (mt‐Kaede) to analyze the dynamics of mitochondrial fission in BY‐2 suspension cells. Analysis of the photoactivatable fluorescence of mt‐Kaede suggested that the fission process is dominant during mitosis. This finding was confirmed by an electron microscopic analysis of the size distribution of mitochondria in BY‐2 suspension cells at various stages. Cellular proteins interacting with Myc‐tagged dynamin‐related protein 3A/3B (AtDRP3A and AtDRP3B) were immunoprecipitated with anti‐Myc antibody‐conjugated beads and subsequently identified by microcapillary liquid chromatography–quadrupole time‐of‐flight mass spectrometry (CapLC Q‐TOF) MS/MS. The identified proteins were broadly associated with cytoskeletal (microtubular), phosphorylation, or ubiquitination functions. Mitotic phosphorylation of AtDRP3A/AtDRP3B and mitochondrial fission at metaphase were inhibited by treatment of the cells with a CdkB/cyclin B inhibitor or a serine/threonine protein kinase inhibitor. The fate of AtDRP3A/3B during the cell cycle was followed by time‐lapse imaging of the fluorescence of Dendra2‐tagged AtDRP3A/3B after green‐to‐red photoconversion; this experiment showed that AtDRP3A/3B is partially degraded during interphase. Additionally, we found that microtubules are involved in mitochondrial fission during mitosis, and that mitochondria movement to daughter cell was limited as early as metaphase. Taken together, these findings suggest that mitotic phosphorylation of AtDRP3A/3B promotes mitochondrial fission during plant cell mitosis, and that AtDRP3A/3B is partially degraded at interphase, providing mechanistic insight into the mitochondrial morphological changes associated with cell‐cycle transitions in BY‐2 suspension cells. 相似文献
4.
Mitochondria isolated from 2-day-old etiolated soybean (Glycine max) seedlings which had been subjected to various heat shock treatments, i.e. (A) 28°C (2 h), (B) 38°C (2 h), (C) 38°C (2 h)-42.5°C (0.5 h), and (D) 38°C (2 h)-42.5°C (0.5 h)-28°C (4 h), were monitored for O2 uptake using an oxygen electrode. Mitochondria isolated after all four heat shock treatments were active in O2 consumption at 28°C in response to succinate and ADP (derived P/O ratios were 1.6, 1.7, 1.3, and 1.3, respectively.) The mitochondria from all four treatments were also active in O2 uptake at 42.5°C. However, only mitochondria isolated after treatment (C) were tightly coupling at 42.5°C (derived ADP/O ratio was about 1.4). Combined with our earlier findings on the subcellular localization of heat shock proteins, our present data demonstrate that association of heat shock proteins with mitochondria by treatment (C) enables them to phosphorylate at 42.5°C (i.e. they become thermotolerant). Isolated mitochondria from treatment (C) and treatment (A) were compared by electron microscopy. They appeared to be very similar and no significant ultrastructural differences were noted. 相似文献
5.
6.
A d-aminoacylase-producing microorganism, strain DA181, isolated from soil was identified as Alcaligenes denitrificans subsp. denitrificans. This strain produced about 29,300 units (micromoles of product formed per hour) of d-aminoacylase and 2,300 units of l-aminoacylase per gram of cells (wet weight) when cultivated in a medium containing 1% N-acetyl-dl-leucine as the carbon source. The d-aminoacylase was purified 345-fold. The specific activity of the purified enzyme was 108,600 units per mg of protein when N-acetyl-d-methionine was used as a substrate. The apparent molecular weight was 58,000, as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. N-Acetyl-d-methionine was the favored substrate, followed by N-acetyl-d-phenylalanine. This enzyme had a high stereospecificity, and its hydrolysis of N-acetyl-l-amino acids was almost negligible. 相似文献
7.
蟹蛛科(Thomisidae)是蜘蛛目中一个大科,常见于农田和园林,与人类关系密切。蟹蛛行动缓慢,常隐蔽于树叶、花草丛中捕食害虫。色泽艳丽,形态多样,并有拟态现象。 中国的蟹蛛研究报道尚不多,笔者近年来通过镜检大量标本,初步鉴定23属70种。本文限于篇幅,将新种先作一报道。我国幅员广阔,蟹蛛种数决不止此数,尚待今后进一步研究。 相似文献
8.
9.
Chen Guanfang Institute of Vertebrate Paleontology Paleoanthropology Academia Sinkica 《古脊椎动物学报》1988,(4)
<正> The mastodont materials described in the present paper, associated with Amblycastor tunggurensis, Amphicyon sp., Anchitherium cf. aurelianense, Brachypotherium sp., ?Chilotherium sp., Stephanocemas thomsoni, Dicrocerus grangeri, Eotragus sp., Oioceros grangeri and O. noverca, were collected from the Haramagai formation of Junggar Basin in Xinjiang by an IVPP field team in 1982. The geology of the area has already been reported by Tong (1986, 1987). The mastodont fossils found at 5 sites on the north and west banks of the Ulungur river, Junggar Basin are abundant. They comprise 5 species, among which is one new species.The author is greatly indebted to the IVPP field team (Tong, Y., the head of the 1982 Junggar field team) allocating the mastodont materials for me to study. 相似文献
10.
流行性出血热病毒R22株cDNA克隆及其特异性鉴定 总被引:3,自引:0,他引:3
用家鼠型流行性出血热病毒R22株RNA,经polyA接尾,以Oligo-dT做引物,合成cDNA。用pUC18为载体转染E.coli Mc1061,建立cDNA克隆。再经菌落杂交,选择病毒特异性的5个阳性克隆制成缺口翻译探针,与病毒RNA3个片段进行反杂交,确定RNA片段的特异性。结果表明,3个克隆为中(M)片段的cDNA,另两个分别为大(L)和小(S)片段cDNA。核苷酸序列分析证明,克隆的DNA中含病毒特异的核苷酸序列。 相似文献