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111.
C. P. A. Strome P. L. De Santis R. L. Beaudoin 《In vitro cellular & developmental biology. Plant》1979,15(7):531-536
Summary Cultures of embryonic rat brain and liver, and embryonic turkey brain were inoculated with sporozoites ofPlasmodium berghei. Sporozoites succeeded in establishing exoerythrocytic infections in approximately 10% of the cultures. The exoerythrocytic
parasites developed to a late schizont stage with some showing early segmentation although free merozoites were not observed.
The morphology and rate of development of the exoerythrocytic parasites in culture appear similar to that seen in vivo.
This work was supported by ONR Contract No. N00014-76-C-1132 and Naval Medical Research and Development Command, Research
Work Unit No. M0095PN.002.5058. the opinions and assertions contained herein are the private ones of the authors and are not
to be construed as official or reflecting the views of the Navy Department or the naval service at large. The experiments
reported herein were conducted according to the principles set forth in theGuide for the Care and Use of Laboratory Animals, Institute of Laboratory Resources, National Research Council, DHEW, Pub. No. (NIH) 74-23. 相似文献
112.
Partially purified preparations of Phe- and Tyr-tRNA synthetases were obtained from seed or seedlings of Phaseolus aureus, Delonix regia and Caesalpinia tinctoria, and the ability of a variety of structural analogues of Phe or Tyr to act as alternative substrates or inhibitors was tested. 3-Hydroxymethylphenylalanine, a natural product of C. tinctoria, formed a particularly effective substrate for the Tyr-tRNA synthetase from P. aureus. The structural features commensurate with substrate activity in an analogue molecule are discussed. 相似文献
113.
JOSE A. O'DALY 《The Journal of eukaryotic microbiology》1975,22(4):550-555
SYNOPSIS. Five proteins capable of stimulating [3 H]thymidine uptake by Trypanosoma cruzi in vitro were isolated from fetal calf serum by (NH4 )2 SO4 precipitation and ion exchange column chromatography. The proteins were partially characterized by immunodiffusion, immunoelectrophoresis, polyacrylamide gel disc electrophoresis, and SDS electrophoresis. As estimated by SDS electrophoresis, using 4 standards, the molecular weight of protein 1 was 100,000, that of protein 2 was 76,000. and that of proteins 3–5 was 68,000 daltons. 相似文献
114.
On the ecology of Trichocercidae (Rotifera) 总被引:2,自引:2,他引:0
A material consisting of 46 trichocercid rotifers from diverse waters in south and central Sweden was analyzed to reveal their relationships to their substrate. Most species were found in a wide variety of periphytic environments, but a few seemed to be specialized on bogs or psammon, respectively. Several trichocercids are generally regarded as plankters, but some of them obviously invade the open water only on certain occasions. A few species of Trichocerca are registered as indicators of eutrophy, but in some cases only a planktic occurrence may be regarded as indicating. On the other hand, hypertrophic environments are generally avoided. Trichocerca similis prefers polyhumic environments, T. uncinata oligotrophic and running-water conditions. The occurrence is often best explained by studying the food choice. 相似文献
115.
《Mycoscience》2014,55(5):405-416
Boletus edulis is a well-known ectomycorrhizal mushroom. Although cultivation has been widely attempted, no artificial fruiting has been achieved owing to difficulties associated with mycorrhizal synthesis and acclimatization in fields. We collected fifteen B. edulis basidiomata samples from locations in Japan and identified them microscopically and by phylogenetic analysis of their nuclear ribosomal internal transcribed spacer (ITS) regions. Pure culture isolates of B. edulis were established efficiently on malt extract agar medium, and one isolate, EN-63, was inoculated to axenic Pinus densiflora seedlings in vitro. Brownish ectomycorrhizal tips were observed on the pine lateral roots within four months of inoculation. Ten pine seedlings that formed ectomycorrhizae were acclimatized under laboratory and greenhouse conditions. At four months after transplant, mycorrhizal colonization by B. edulis was observed on newly grown root tips under laboratory conditions, but no B. edulis ectomycorrhiza survived under greenhouse conditions. These results suggest that B. edulis ectomycorrhizae synthesized in vitro with P. densiflora requires additional steps for acclimatization to greenhouse conditions. 相似文献
116.
蛹虫草是一种可利用大米、小麦等谷物培育的名贵药用真菌,其采收后的菌糠里仍富含许多生物活性物质。本研究立足于蛹虫草菌糠多糖,先分析其化学抗氧化活性,再以H2O2诱导氧化应激损伤的LO2细胞为模型,评价其对肝细胞氧化损伤的保护作用,进而解析活性多糖的单糖组分。结果显示,菌糠多糖能够有效清除DPPH自由基、羟基(?OH)自由基和ABTS自由基,EC50分别为0.26mg/mL、1.03mg/mL、0.57mg/mL,提示其具有良好的抗氧化能力;在H2O2诱导氧化应激损伤的LO2细胞中,菌糠多糖能有效地保护细胞形态的完整性,并且随浓度梯度递增式地提高细胞存活率,当多糖浓度为5mg/mL时,细胞存活率可达91.83%;在分析其作用机制上,与模型组对比,菌糠多糖能通过调节细胞抗氧化酶SOD(提高4.91倍)和CAT(提高3.40倍)的表达来清除ROS含量(P<0.01),降低氧化损害;经检测,虫草菌糠活性多糖主要含有葡萄糖、甘露糖、半乳糖、阿拉伯糖、葡萄糖醛酸、木糖、半乳糖醛酸、鼠李糖和岩藻糖等单糖。研究结果表明蛹虫草MF27菌糠多糖具有保护肝细胞氧化损伤的作用,为进一步开发和利用虫草菌糠提供了重要理论依据。 相似文献
117.
118.
119.
桔黄赛多孢菌Scedosporium aurantiacum是慢性肺病患者的常见呼吸道定植菌,在免疫缺陷人群中可引起侵袭性感染,致死率高,但由于致病机理不明,目前仍然缺乏有效的防控手段。我们在前期研究中,通过差异蛋白组学及酶工程技术发现分泌胰蛋白酶是桔黄赛多孢菌的潜在毒力因子,目前对这种蛋白酶的遗传信息、结构及致病机制并不清楚。本研究用Superdex S-200分子筛和DEAE-Sepharose离子交换两种填料将这种蛋白酶分离纯化出来,通过酶谱验证了纯化效果。进一步研究发现,这种胰蛋白酶对bFSR、bLSTR和bEKK 3种底物的水解性能最佳,对zFR和bzLR的水解性能最差。酶解最快的反应所对应的Km为6.09μmol/L,Vmax为13.01μmol/L/s,Kcat为23.65/s;酶解最慢的反应所对应的Km为29.94μmol/L,Vmax为11.35μmol/L/s,Kcat为20.63/s。研究结果对于填补赛多孢菌毒力因子研究的空白、针对毒力因子开发新型的抗真菌药物和治疗方法都具有重要意义。 相似文献
120.
野生田头菇菌株的驯化及其子实体营养成分分析 总被引:1,自引:0,他引:1
采自湖南洞庭湖大通湖区芦苇湿地的野生菌株,经鉴定为田头菇Agrocybe praecox。通过驯化实现人工栽培,栽培原料以芦苇屑为主,使用液体菌种和覆土栽培方式,初潮菇平均生物转化率为45.6%。营养成分分析表明:以芦苇屑为栽培培养基,子实体中矿物元素含量分别为K(2 190mg/kg)、Fe(16.2mg/kg)、Mg(59.7mg/kg)、Ca(33.4mg/kg),必需氨基酸含量占比高达44.85%,谷氨酸、蛋氨酸、天冬氨酸含量高,是一种高蛋白、低脂肪、高钾低钠的食用菌。 相似文献