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81.
概述了新型冠状病毒肺炎疫情期间辽宁省食用菌产业生产和管理现状,分析了疫情对辽宁省食用菌产业产前、产中、产后的影响,指出了原辅料准备、菌种(棒)生产、养菌管理、产品销售以及人员用工、交通物流等存在的诸多问题,明确了疫情对食用菌产业结构、销售市场结构、投资市场结构主要的影响因素,提出了应对交通不畅、劳动力匮乏、资金短缺、技术缺乏的具体措施,并对辽宁省食用菌产业健康持续高质量发展提出建议。  相似文献   
82.
TRIM家族是一个结构保守、进化快速的蛋白家族,它参与了细胞凋亡、周期调控、细胞对病毒的应答等重要的生命过程。结构上的保守预示着TRIM家族可能是以一种共同的机制参与各种生命过程的。最近的一些研究显示TRIM家族可能是一类新的RING指泛素连接酶。  相似文献   
83.
To maintain genomic stability, chromosome architecture needs to be tightly regulated as chromosomes undergo condensation during prophase and separation during anaphase, but the mechanisms remain poorly understood. Here, we show that the Plk1-binding protein PICH and Plk1 kinase coordinately maintain chromosome architecture during prometaphase. PICH knockdown results in a loss of Plk1 from the chromosome arm and an increase in highly disorganized “wavy” chromosomes that exhibit an “open” or “X-shaped” configuration, consistent with a loss of chromosome arm cohesion. Such chromosome disorganization occurs with essentially no change in the localization of condensin or cohesin on chromosomes. Interestingly, the chromosome disorganization could be prevented by treatment with a topoisomerase II inhibitor ICRF-193, suggesting that the PICH–Plk1 complex normally maintains chromosome architecture in a manner that involves topoisomerase II activity. PICH knockdown does not affect initial chromosome compaction at prophase but causes anaphase DNA bridge formation and failed abscission. Our studies suggest that the PICH–Plk1 complex plays a critical role in maintaining prometaphase chromosome architecture.  相似文献   
84.
目的评价硫糖铝在胃内对H.pyloriVacA IgY型抗体的保护作用,为制备H.pyloriVacA IgY型抗体口服剂提供实验依据。方法大量诱导工程菌DH5α-vacA-pQE30,表达并纯化重组蛋白VacA。以VacA为抗原接种洛曼母鸡,制备纯化的IgY。建立H.pylori感染的小鼠模型,在不同浓度的IgY液中分别加入30%硫糖铝,灌胃后观察胃黏膜慢性炎症反应以评价硫糖铝在胃内对VacA IgY的保护作用。结果在小鼠胃内,0.5mg IgY+30%硫糖铝/天灌胃小鼠即可有效防治H.pylori感染引起的胃黏膜损害,与不加硫糖铝比较,其效果提高了8倍。结论 30%以上的硫糖铝在小鼠胃内可增强VacA IgY对低pH和胃蛋白酶的耐受能力,是较理想的抗H.pyloriVacA IgY型抗体保护剂。  相似文献   
85.
Jurkat T cells were found to adhere to a tissue culture flask or cover glass when 10% fetal bovine serum (FBS) was withdrawn. However, the cells adhered to extracellular matrix, especially fibronectin, regardless of the presence of FBS. We hypothesized that a substance in FBS inhibits T cells' adherence. Through a purification and identification procedure performed on the substance, bovine serum albumin (BSA) was found to inhibit T cell adhesion. BSA, furthermore, inhibited the adhesion of human primary cultured T cells. These results suggest a novel function for albumin as a T cell adhesion inhibitor.  相似文献   
86.
以冬小麦为实验材料 ,研究了三种不同浓度的Co(C6H9N3 O2 ) 2 Cl2 对冬小麦种子萌发和苗期生长的影响。结果表明 :不同浓度的Co(C6H9N3 O2 ) 2 Cl2 均具有生物活性 ,它们对小麦的发芽势、生长势、发芽率、种子萌发过程中淀粉酶活力、根系发育以及生物量均有明显的生理作用。  相似文献   
87.
Sexual behavior between males and females, as well as between males, is described and discussed for the cerambycid beetlePhytoecia rufiventris. The beetles' taxis toward plants taller than average height brings the sexes together from a distance. A male may mount another individual (male or female) and attempt copulation without sex discrimination. The male can discern the sex of another individual only when the terminal part of his abdomen touches the ventral surface of the fifth visible sternite of the latter. No evidence of a sex pheromone is found in this species. Within 1.5–5.5 cm the substrateborne vibrations produced by a moving individual may be the important factor which elicits males to approach a moving individual and attempt copulation. If a female is receptive when a male touches her, he can copulate with her without any courtship display. However, if the female runs away and appears unreceptive, the male will perform courtship displays. Copulation is usually terminated by males. Homosexual behavior between males is discussed.  相似文献   
88.
从云南程海湖分离到473株淡水真菌,用滤纸片法测定其抗菌活性,活性菌株经显微形态观察进行分类鉴定。结果显示有290株菌对至少1种病原菌具有抗菌活性,占总菌株数的61.31%;高抗菌活性菌株59株(抑菌圈直径≥15 mm),占总菌株的12.47%。将具有抗菌活性的菌株鉴定为46个属,优势属为青霉属(Penicillium)、曲霉属(Aspergillus)和枝孢属(Cladosporium)。  相似文献   
89.
Cranial radiotherapy induces progressive and debilitating cognitive deficits, particularly in long-term cancer survivors, which may in part be caused by the reduction of hippocampal neurogenesis. Previous studies suggested that voluntary exercise can reduce the cognitive impairment caused by radiation therapy. However, there is no study on the effect of forced wheel exercise and little is known about the molecular mechanisms mediating the effect of exercise. In the present study, we investigated whether the forced running exercise after irradiation had the protective effects of the radiation-induced cognitive impairment. Sixty-four Male Sprague–Dawley rats received a single dose of 20 Gy or sham whole-brain irradiation (WBI), behavioral test was evaluated using open field test and Morris water maze at 2 months after irradiation. Half of the rats accepted a 3-week forced running exercise before the behavior detection. Immunofluorescence was used to evaluate the changes in hippocampal neurogenesis and Western blotting was used to assess changes in the levels of mature brain-derived neurotrophic factor (BDNF), phosphorylated tyrosine receptor kinase B (TrkB) receptor, protein kinase B (Akt), extracellular signal-regulated kinase (ERK), calcium-calmodulin dependent kinase (CaMKII), cAMP-calcium response element binding protein (CREB) in the BDNF–pCREB signaling. We found forced running exercise significantly prevented radiation-induced cognitive deficits, ameliorated the impairment of hippocampal neurogenesis and attenuated the down-regulation of these proteins. Moreover, exercise also increased behavioral performance, hippocampal neurogenesis and elevated BDNF–pCREB signaling in non-irradiation group. These results suggest that forced running exercise offers a potentially effective treatment for radiation-induced cognitive deficits.  相似文献   
90.
There is no commercial or industrial-scale process for the remediation of black liquor using microorganisms to date. One of the most important causes is that most microorganisms are not able to use lignin as their principal metabolic carbon or energy source. The bacterial strain Comamonas sp. B-9 has shown remarkable ability to degrade kraft lignin and decolorize black liquor using lignin as its principal metabolic carbon and energy source. This report looks at the depolymerization and decolorization of kraft lignin by Comamonas sp. B-9. The degradation, decolorization, and total carbon removal reached 45, 54, and 47.3 %, respectively, after 7 days treatment. Comamonas sp. B-9 was capable of depolymerizing kraft lignin effectively as analyzed by gel permeation chromatography and decolorization via degrading benzene ring structures as shown using Fourier transform infrared spectroscopy analysis.  相似文献   
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