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191.
为探讨不同营养条件下甜菜夜蛾Spodoptera exigua对甜菜夜蛾核型多角体病毒(Spodoptera exigua multiple nucleopolyhedrovirus,SeMNPV)的敏感性及取食行为响应,本研究通过改变甜菜夜蛾人工饲料配方建立高蛋白低糖(简称高蛋白)、中蛋白中糖(简称中蛋白)、低蛋白高糖(简称低蛋白)3种营养品系,观察不同营养品系幼虫对SeMNPV的敏感性,以及染毒前后对不同营养饲料的取食趋性.结果 显示,高蛋白、中蛋白、低蛋白3种营养品系中,SeMNPV对甜菜夜蛾初孵幼虫的半数致死浓度(LC50)分别是1.76×105 PIB/mL、2.85×105 PIB/mL和2.10×104 PIB/mL.统计分析显示,中蛋白品系的LC50显著高于低蛋白品系,高蛋白品系的LC50同其余两种品系相比无显著性差异.以8×105 PIB/mL浓度的病毒饲喂甜菜夜蛾初孵幼虫,3种营养品系的半数致死时间(LT50)分别是6.07 d、6.85 d和5.20 d,中蛋白品系的存活时间显著长于低蛋白品系,高蛋白品系的LT50同其余两种品系相比无显著性差异.未染毒状态下,低龄幼虫偏向蛋白质含量较高的饲料,而高龄幼虫则偏向于高糖的饲料;染毒状态下,甜菜夜蛾各龄期幼虫都偏向于取食蛋白质含量较高的饲料.以上研究结果表明,营养条件的变化可以显著影响甜菜夜蛾幼虫对SeMNPV的敏感性,染毒后幼虫明显偏向于蛋白质含量高的饲料,推测蛋白质可能有助于提高甜菜夜蛾幼虫对SeMNPV的抵抗力.  相似文献   
192.
为探明北京地区芦苇(Phragmites australis)的资源状态和多样性, 实地考察北京主要河流、湿地和水库, 发现北京地区芦苇总生长面积已超过600 hm2。芦苇染色体倍性以八倍体为主, 四倍体次之。在面积较大的湿地内, 八倍体单一芦苇群落占据优势地位; 而在城市的浅河内有形态和遗传性多样的混合种群。研究表明, 植物性状和倍性水平之间无显著相关性。在小清河发现了6种形态各异的芦苇克隆, 均属于叶绿体DNA片段的P单倍型; 其单倍体基因组大小为(0.499±0.019) pg, 变异系数为3.8%。这表明表型与单倍型之间也不具相关性。此外, 发现1个具有变叶特性的芦苇, 将其命名为金条芦苇。北京地区芦苇形态和遗传多样性为研究芦苇基因型与环境适应性之间的关系提供了珍贵的资源。  相似文献   
193.
Ti  Dongdong  Bai  Miaomiao  Li  Xiaolei  Wei  Jianshu  Chen  Deyun  Wu  Zhiqiang  Wang  Yao  Han  Weidong 《中国科学:生命科学英文版》2021,64(3):363-371
Impaired tumor-specific effector T cells contribute to tumor progression and unfavorable clinical outcomes. As a compensatory T cell-dependent cancer immunoediting strategy, adoptive T cell therapy(ACT) has achieved encouraging therapeutic results,and this strategy is now on the center stage of cancer treatment and research. ACT involves the ex vivo stimulation and expansion of tumor-infiltrating lymphocytes(TILs) with inherent tumor reactivity or T cells that have been genetically modified to express the cognate chimeric antigen receptor or T cell receptor(CAR/TCR), followed by the passive transfer of these cells into a lymphodepleted host. Primed T cells must provide highly efficient and long-lasting immune defense against transformed cells during ACT. Anin-depth understanding of the basic mechanisms of these living drugs can help us improve upon current strategies and design better next-generation T cell-based immunotherapies. From this perspective, we provide an overview of current developments in different ACT strategies, with a focus on frontier clinical trials that offer a proof of principle. Meanwhile, insights into the determinants of ACT are discussed, which will lead to more rational, potent and widespread applications in the future.  相似文献   
194.
Advances in high-throughput sequencing(HTS)have fostered rapid developments in the field of microbiome research,and massive microbiome datasets are now being generated.However,the diversity of software tools and the complexity of analysis pipelines make it difficult to access this field.Here,we systematically summarize the advantages and limitations of micro-biome methods.Then,we recommend specific pipelines for amplicon and metagenomic analyses,and describe commonly-used software and databases,to help researchers select the appropriate tools.Furthermore,we introduce statistical and visualization methods suit-able for microbiome analysis,including alpha-and beta-diversity,taxonomic composition,difference compar-isons,correlation,networks,machine learning,evolu-tion,source tracing,and common visualization styles to help researchers make informed choices.Finally,a step-by-step reproducible analysis guide is introduced.We hope this review will allow researchers to carry out data analysis more effectively and to quickly select the appropriate tools in order to efficiently mine the bio-logical significance behind the data.  相似文献   
195.
Ai  Xiaopeng  Dong  Xing  Guo  Ying  Yang  Peng  Hou  Ya  Bai  Jinrong  Zhang  Sanyin  Wang  Xiaobo 《Purinergic signalling》2021,17(2):229-240

Adenosine triphosphate (ATP) and its metabolites adenosine diphosphate, adenosine monophosphate, and adenosine in purinergic signaling pathway play important roles in many diseases. Activation of P2 receptors (P2R) channels and subsequent membrane depolarization can induce accumulation of extracellular ATP, and furtherly cause kinds of diseases, such as pain- and immune-related diseases, cardiac dysfunction, and tumorigenesis. Active ingredients of traditional Chinese herbals which exhibit superior pharmacological activities on diversified P2R channels have been considered as an alternative strategy of disease treatment. Experimental evidence of potential ingredients in Chinese herbs targeting P2R and their pharmacological activities were outlined in the study.

  相似文献   
196.
The ADP-ribosylation factor-like proteins (ARLs) have been proved to regulate the malignant phenotypes of several cancers. However, the exact role of ARLs in gastric cancer (GC) remains elusive. In this study, we systematically investigate the expression status, interactive relations, potential pathways, genetic variations and clinical values of ARLs in GC. We find that ARLs are significantly dysregulated in GC and involved in various cancer-related pathways. Subsequently, machine learning models identify ARL4C as one of the two most significant clinical indicators among ARLs for GC. Furthermore, ARL4C silencing remarkably inhibits the growth and metastasis of GC cells both in vitro and in vivo. Moreover, enrichment analysis indicates that ARL4C is highly correlated with TGF-β1 signalling. Correspondingly, TGF-β1 treatment dramatically increases ARL4C expression and ARL4C knockdown inhibits the phosphorylation level of Smads, downstream factors of TGF-β1. Meanwhile, the coexpression of ARL4C and TGF-β1 worsens the prognosis of GC patients. Our work comprehensively demonstrates the crucial role of ARLs in the carcinogenesis of GC and the specific mechanisms underlying the GC-promoting effects of TGF-β1. More importantly, we uncover the great promise of ARL4C-targeted therapy in improving the efficacy of TGF-β1 inhibitors for GC patients.  相似文献   
197.
The use of human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) is limited in drug discovery and cardiac disease mechanism studies due to cell immaturity. Micro-scaled grooves can promote the maturation of cardiomyocytes by aligning them in order, but the mechanism of cardiomyocytes alignment has not been studied. From the level of calcium activity, gene expression and cell morphology, we verified that the W20H5 grooves can effectively promote the maturation of cardiomyocytes. The transient receptor potential channels (TRP channels) also play an important role in the maturation and development of cardiomyocytes. These findings support the engineered hPSC-CMs as a powerful model to study cardiac disease mechanism and partly mimic the myocardial morphological development. The important role of the TRP channels in the maturation and development of myocardium is first revealed.  相似文献   
198.
目的探讨支气管镜肺泡灌洗联合抗生素对小儿重症肺炎的疗效及对痰细菌清除率和其他指标的影响。方法选取我科收治的重症肺炎患儿126例,分为研究组及对照组,各63例。其中研究组在常规治疗基础上联合支气管镜肺泡灌洗及局部应用抗生素治疗,对照组采用常规治疗,比较2组患者的临床治疗效果。结果治疗后,研究组的临床有效率为90.5%,高于对照组的76.2%(χ~2=4.629,P=0.031);治疗后研究组患者的痰液中病菌清除率为77.7%,显著高于对照组的57.2%(χ~2=6.110,P=0.013);治疗后研究组患者的相关炎性指标(高敏C反应蛋白、肿瘤坏死因子α及白介素-6)均较对照组显著降低(t=3.522、4.912、4.183,P=0.033、0.032、0.033);治疗后研究组患者的相关血气指标(动脉血氧分压及氧合指数)均较对照组显著升高,而二氧化碳分压较对照组显著降低(t=3.612、3.312、6.162,P=0.039、0.040、0.028)。结论 BAL联合抗生素对小儿重症肺炎的疗效更为显著,值得临床推广应用。  相似文献   
199.
目的评价一种以乙醇和银离子为主要成分的免洗手消毒液(安可信)的效果及其安全性。方法采用悬液定量杀菌试验、消毒剂对手消毒现场试验、急性经口毒性试验和小鼠骨髓嗜多染红细胞微核试验等方法,研究该免洗手消毒液杀菌效果以及安全性。结果银离子浓度为41.6 mg/kg、乙醇含量为54.4%(w/w)的该免洗手消毒液作用1 min,对大肠埃希菌、金黄色葡萄球菌和铜绿假单胞菌平均杀灭对数值>3.00;对白假丝酵母菌的平均杀灭对数值>4.00。该免洗手消毒液原液经37 ℃恒温培养箱保存3个月后,样品乙醇含量下降率为0.37%,银离子含量无下降。该免洗手消毒液对小鼠急性经口毒性LD50>5 000 mg/kg,对新西兰家兔皮肤无刺激性,小鼠骨髓嗜多染红细胞微核试验结果为阴性。结论安可信银离子免洗手消毒液对细菌和真菌具有较好消毒作用;对人体无皮肤刺激;各项指标均符合国家要求。  相似文献   
200.
补充益生菌对功能性腹泻患者焦虑抑郁状态的影响   总被引:1,自引:0,他引:1  
目的探讨益生菌对功能性腹泻患者临床症状和心理健康的影响。方法将2019年3月至2019年12月在广东省肇庆市高要区人民医院消化内科门诊收治的伴有焦虑抑郁状态的90例功能性腹泻住院病人随机分为试验组、对照组A、对照组B。三组受试者均口服匹维溴铵,试验组口服双歧杆菌四联活菌,对照组A服用氟西汀,对照组B未给其他药物治疗,疗程均为1个月。治疗前后,比较患者大便次数及性状、汉密尔顿焦虑量表(HAMA)和汉密尔顿抑郁量表(HAMD)评分。结果治疗前三组患者每周排便不同次数的人数比较,差异无统计学意义(P0.05)。治疗第3周和第4周后,与对照组A相比,对照组B和试验组的排便不同次数的人数差异具有统计学意义(P0.05)。治疗第4周后,试验组与对照组B的排便不同次数的人数比较,差异具有统计学意义(P0.05)。治疗前3组患者Bristol粪便性状评分比较差异无统计学意义(P0.05)。治疗第3和第4周后,与对照组A相比,对照组B和试验组的Bristol粪便性状评分比较,差异有统计学意义(P0.05)。治疗第4周后,试验组与对照组B的Bristol粪便性状评分比较,差异有统计学意义(P0.05)。治疗后与对照组A比较,对照组B和试验组HAMA评分和HAMD评分显著低于对照组A,且差异具有统计学意义(P0.05)。与对照组B比较,试验组HAMA评分和HAMD评分显著低于对照组B(P0.05)。结论通过补充益生菌可调节功能性腹泻患者腹泻次数,提高功能性腹泻患者生活质量,改善患者焦虑抑郁症状。  相似文献   
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