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991.
以现有乳酸菌信息为依据,利用汉字foxbase2.10进行数据处理,研制出一套乳酸菌微机检索软件。该软件的特点:检索速度快,途径灵活,增添、修改、删除、打印方便,各模块性能优良,实用性强。  相似文献   
992.
深黄被孢霉高产脂变株的选育及其发酵的研究   总被引:33,自引:0,他引:33  
以深黄被孢霉(Mortierellaisabellina)AS3.3410为出发菌株,经紫外线,硫酸二乙酯和亚硝基胍复合诱变处理,选育成功高产脂深黄被抱霉M018变株,其摇瓶培养菌体油脂含量达65.6%,比出发菌株提高133%。60m3罐三级发酵培养菌体油脂含量高达79.2%,生物量达37.8g/L.气相色谱分析表明变株M018r-亚麻酸的含量比出发菌株提高了53%。连续传代试验表明M018是一稳定的变株。该变株油脂合成的最佳碳源为葡萄糖,最佳氮源为酵母膏,最佳C/N为  相似文献   
993.
活菌制剂活菌数急剧衰降的原因与减缓衰降的方法   总被引:4,自引:0,他引:4  
市售活菌制剂口服液活菌数急剧衰降的原因是营养缺乏,特别是缺乏部分氨基酸及某些维生素。增加动物性蛋白胨及强化酵母膏,添加适量维生素可使活菌数一年后保持在10/ml以上。  相似文献   
994.
本文研究了球形芽孢杆菌(Bacillussphaericus)C3-41超氧化物歧化酶(SOD)的产生条件和部分特性。当C3-41菌株处于孢子囊中期时为产SOD酶高峰期,在30℃下的平板培养物及培养基起始pH为中性(pH7.0)时产生的SOD酶比活最高,经硫酸铵分级沉淀,DEAE-32离子交换层析和SephadexG-100凝胶过滤提纯了SOD酶。此酶属Mn-SOD,在25~35℃和pH5~9范围内较稳定,但在55℃下10min完全失活。  相似文献   
995.
介绍一种快速提取禽源性大肠埃希氏菌外膜蛋白的方法。该法是对Kapur等发表的方法的改进。全过程只需超速离心一次,比Kapur等的方法缩短了4h。所得样品可直接用于禽源性大肠埃希氏菌外膜蛋白模式的测定。  相似文献   
996.
Pain is a multidimensional perception that includes unpleasant somatosensory and affective experiences; however, the underlying neural circuits that mediate different components of pain remain elusive. Although hyperactivity of basolateral amygdala glutamatergic (BLAGlu) neurons is required for the somatosensory and emotional processing of pain, the precise excitatory inputs to BLAGlu neurons and their roles in mediating different aspects of pain are unclear. Here, we identified two discrete glutamatergic neuronal circuits in male mice: a projection from the insular cortex glutamatergic (ICGlu) to BLAGlu neurons, which modulates both the somatosensory and affective components of pain, and a projection from the mediodorsal thalamic nucleus (MDGlu) to BLAGlu neurons, which modulates only the aversive-affective component of pain. Using whole-cell recording and fiber photometry, we found that neurons within the IC→BLA and MD→BLA pathways were activated in mice upon inflammatory pain induced by injection of complete Freund’s adjuvant (CFA) into their paws. Optical inhibition of the ICGlu→BLA pathway increased the nociceptive threshold and induced behavioral place preference in CFA mice. In contrast, optical inhibition of the MDGlu→BLA pathway did not affect the nociceptive threshold but still induced place preference in CFA mice. In normal mice, optical activation of the ICGlu→BLA pathway decreased the nociceptive threshold and induced place aversion, while optical activation of the MDGlu→BLA pathway only evoked aversion. Taken together, our results demonstrate that discrete ICGlu→BLA and MDGlu→BLA pathways are involved in modulating different components of pain, provide insights into its circuit basis, and better our understanding of pain perception.  相似文献   
997.
There is increasing amount of evidence indicating the close interplays between the replication cycle of SARS-CoV-2 and the autophagy-lysosome pathway in the host cells. While autophagy machinery is known to either assist or inhibit the viral replication process, the reciprocal effects of the SARS-CoV-2 on the autophagy-lysosome pathway have also been increasingly appreciated. More importantly, despite the disappointing results from the clinical trials of chloroquine and hydroxychloroquine in treatment of COVID-19, there is still ongoing effort in discovering new therapeutics targeting the autophagy-lysosome pathway. In this review, we provide an update-to-date summary of the interplays between the autophagy-lysosome pathway in the host cells and the pathogen SARS-CoV-2 at the molecular level, to highlight the prognostic value of autophagy markers in COVID-19 patients and to discuss the potential of developing novel therapeutic strategies for COVID-19 by targeting the autophagy-lysosome pathway. Thus, understanding the nature of such interactions between SARS-CoV-2 and the autophagy-lysosome pathway in the host cells is expected to provide novel strategies in battling against this global pandemic.  相似文献   
998.
Symbiotic microbes play a crucial role in regulating parasite–host interactions; however, the role of bacterial associates in parasite–host interactions requires elucidation. In this study, we showed that, instead of introducing numerous symbiotic bacteria, dispersal of 4th-stage juvenile (JIV) pinewood nematodes (PWNs), Bursaphelenchus xylophilus, only introduced few bacteria to its vector beetle, Monochamus alternatus (Ma). JIV showed weak binding ability to five dominant bacteria species isolated from the beetles’ pupal chamber. This was especially the case for binding to the opportunistic pathogenic species Serratia marcescens; the nematodes’ bacteria binding ability at this critical stage when it infiltrates Ma for dispersal was much weaker compared with Caenorhabditis elegans, Diplogasteroides asiaticus, and propagative-stage PWN. The associated bacterium S. marcescens, which was isolated from the beetles’ pupal chambers, was unfavorable to Ma, because it caused a higher mortality rate upon injection into tracheae. In addition, S. marcescens in the tracheae caused more immune effector disorders compared with PWN alone. Ma_Galectin2 (MaGal2), a pattern-recognition receptor, was up-regulated following PWN loading. Recombinant MaGal2 protein formed aggregates with five dominant associated bacteria in vitro. Moreover, MaGal2 knockdown beetles had up-regulated prophenoloxidase gene expression, increased phenoloxidase activity, and decreased PWN loading. Our study revealed a previously unknown strategy for immune evasion of this plant pathogen inside its vector, and provides novel insights into the role of bacteria in parasite–host interactions.  相似文献   
999.
1000.
This study aimed to explore the clinical practice of phospholipid metabolic pathways in COVID-19. In this study, 48 COVID-19 patients and 17 healthy controls were included. Patients were divided into mild (n=40) and severe (n=8) according to their severity. Phospholipid metabolites, TCA circulating metabolites, eicosanoid metabolites, and closely associated enzymes and transfer proteins were detected in the plasma of all individuals using metabolomics and proteomics assays, respectively. 30 of the 33 metabolites found differed significantly (P<0.05) between patients and healthy controls (P<0.05), with D-dimmer significantly correlated with all of the lysophospholipid metabolites (LysoPE, LysoPC, LysoPI and LPA). In particular, we found that phosphatidylinositol (PI) and phosphatidylcholine (PC) could identify patients from healthy controls (AUC 0.771 and 0.745, respectively) and that the severity of the patients could be determined (AUC 0.663 and 0.809, respectively). The last measurement before discharge also revealed significant changes in both PI and PC. For the first time, our study explores the significance of the phospholipid metabolic system in COVID-19 patients. Based on molecular pathway mechanisms, three important phospholipid pathways related to Ceramide-Malate acid (Cer-SM), Lysophospholipid (LPs), and membrane function were established. Clinical values discovered included the role of Cer in maintaining the inflammatory internal environment, the modulation of procoagulant LPA by upstream fibrinolytic metabolites, and the role of PI and PC in predicting disease aggravation.  相似文献   
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