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201.
Triatomines display most of their activities during the night. Before sunrise, they search, select and occupy adequate shelters to stay during the photophase, avoiding exposure to diurnal predators. In this work, we first explored the interactions between individuals of the same or different species in the shelter selection process of Triatoma infestans (Klug 1834) and Rhodnius prolixus (Stål 1859). When two groups of insects (either of different nutritional status, nymphal instar or species) were released together over an experimental arena containing two identical shelters, all nymphs were distributed randomly, suggesting the absence of intra- and inters-pecific interactions. Secondly, we analysed their preferences for particular features of shelters by releasing one group of insects (either T. infestans or R. prolixus) over an arena containing two different refuges. Nymphs exhibited preferences for darker shelters with a vertical orientation of its substrate and elevated from the ground, highlighting the importance of such features in a shelter selection context. We conclude that these species disregard the presence of other individuals but evaluate certain characteristics of the shelters to choose them. This information may contribute to understanding the colonization/recolonization dynamic processes of these Chagas disease vectors.  相似文献   
202.
仿脑组织体模是指可以有效模拟人脑组织形状、性质的等效材料组织或数字模型,可以在实验中代表人脑组织的某些生理特性从而达到特定的研究目标,根据其物理形态,通常可分为固体、液体、数字体模3类。仿脑组织体模具有安全经济,配置简单并且可重复使用的优势,被广泛应用于脑部疾病诊断、系统安全性评估等研究。本文就仿脑组织体模的分类、物理特性和脑科学研究应用3方面进行论述,在阐述当前仿脑组织体模与真实脑组织存在一定性质差异的同时也说明其在替代真实脑组织实验上有良好的应用前景。  相似文献   
203.
杨树拟茎点菌溃疡病的研究   总被引:1,自引:0,他引:1  
本病系我国杨树新发生的一种病害。病原菌的分生孢子有2种形状,无色透明、单胞,呈纺缍形孢子大小为1.64—2.74×9.59—13.7μm。线形孢子顶端弯钩状大小为1.37—1.78×15—27.4μm。病原菌适宜生长的培养基为PDA、麦芽粉、豆饼粉培养基;温度为25—32℃和pH6—10。本病于4月下旬发病,5月中下旬分生孢子成熟,6月中下旬为分生孢子飞散高峰期。经室内采用多菌灵、甲基托布津、福美砷的200倍液浸泡插穗30、60、90分钟处理均有药害,采用100—200倍液浸泡10分钟无药害,对病害有防效。造林地幼树可采用上述药剂的100倍液进行刮破病斑涂抹,防效可达87.5%。  相似文献   
204.
BackgroundThe impact of the coronavirus disease 2019 (COVID-19) pandemic on cancer screening participation is a global concern. A national database of screening performance is available in Japan for population-based cancer screening, estimated to cover approximately half of all cancer screenings.MethodsUtilizing the fiscal year (FY) 2017–2020 national database, the number of participants in screenings for gastric cancer (upper gastrointestinal [UGI] series or endoscopy), colorectal cancer (fecal occult blood test), lung cancer (chest X-ray), breast cancer (mammography), and cervical cancer (Pap smear) were identified. The percent change in the number of participants was calculated.ResultsCompared with the pre-pandemic period (FY 2017–2019), in percentage terms FY 2020 recorded the largest decline in gastric cancer UGI series (2.82 million to 1.91 million, percent change was −32.2 %), followed by screening for breast cancer (3.10 million to 2.57 million, percent change was −17.2 %), lung cancer (7.92 million to 6.59 million, percent change was −16.7 %), colorectal cancer (8.42 million to 7.30 million, percent change was −13.4 %), cervical cancer (4.26 million to 3.77 million, percent change was −11.6 %), and gastric cancer via endoscopy (1.02 million to 0.93 million, percent change was −9.0 %).ConclusionThe number of participants in population-based screenings in Japan decreased by approximately 10–30 % during the pandemic. The impact of these declines on cancer detection or mortality should be carefully monitored.  相似文献   
205.
As a distinctive member of the noncoding RNA family, circular RNAs (circRNAs) are generated from single-stranded, covalently closed structures and are ubiquitous in mammalian cells and tissues. Due to its atypical circular architecture, it was conventionally deemed insignificant dark matter for a prolonged duration. Nevertheless, studies conducted over the last decade have demonstrated that this abundant, structurally stable and tissue-specific RNA has been increasingly relevant in diverse diseases, including cancer, neurological disorders, diabetes mellitus and cardiovascular diseases (CVDs). Therefore, regulatory pathways controlled by circRNAs are widely involved in the occurrence and pathological processes of CVDs through their function as miRNA sponges, protein sponges and protein scaffolds. To better understand the role of circRNAs and their complex regulatory networks in CVDs, we summarize current knowledge of their biogenesis and function and the latest research on circRNAs in CVDs, with the hope of paving the way for the identification of promising biomarkers and therapeutic strategies for CVDs.  相似文献   
206.
Coronavirus disease 2019 (COVID-19) is a systemic inflammatory condition with high mortality that may benefit from personalized medicine and high-precision approaches. COVID-19 patient plasma was analysed with targeted proteomics of 1161 proteins. Patients were monitored from Days 1 to 10 of their intensive care unit (ICU) stay. Age- and gender-matched COVID-19-negative sepsis ICU patients and healthy subjects were examined as controls. Proteomic data were resolved using both cell-specific annotation and deep-analysis for functional enrichment. COVID-19 caused extensive remodelling of the plasma microenvironment associated with a relative immunosuppressive milieu between ICU Days 3–7, and characterized by extensive organ damage. COVID-19 resulted in (1) reduced antigen presentation and B/T-cell function, (2) increased repurposed neutrophils and M1-type macrophages, (3) relatively immature or disrupted endothelia and fibroblasts with a defined secretome, and (4) reactive myeloid lines. Extracellular matrix changes identified in COVID-19 plasma could represent impaired immune cell homing and programmed cell death. The major functional modules disrupted in COVID-19 were exaggerated in patients with fatal outcome. Taken together, these findings provide systems-level insight into the mechanisms of COVID-19 inflammation and identify potential prognostic biomarkers. Therapeutic strategies could be tailored to the immune response of severely ill patients.  相似文献   
207.
Indanone derivatives containing meta/para-substituted aminopropoxy benzyl/benzylidene moieties were designed based on the structures of donepezil and ebselen analogs as the cholinesterase inhibitors. The designed compounds were synthesized and their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities were measured. Inhibitory potencies (IC50 values) for the synthesized compounds ranged from 0.12 to 11.92 μM and 0.04 to 24.36 μM against AChE and BChE, respectively. Compound 5 c showed the highest AChE inhibitory potency with IC50 value of 0.12 μM, whereas the highest BChE inhibition was achieved by structure 7 b (IC50=0.04 μM). Structure-activity relationship (SAR) analysis revealed that there is no significant difference between meta and para-substituted derivatives in AChE and BChE inhibition. However, the most potent AChE inhibitor 5 c belongs to meta-substituted compounds, while the most active BChE inhibitor is para-substituted derivative 7 b . The order of enzyme inhibition potency based on the substituted amine group is dimethyl amine>piperidine>morpholine. Compounds containing C=C linkage are more potent AChE inhibitors than the corresponding saturated structures. Molecular docking studies indicated that 5 c interacts with AChE in a very similar way to that observed experimentally for donepezil. The introduced indanone-aminopropoxy benzylidenes could be used in drug-discovery against Alzheimer's disease.  相似文献   
208.
摘要 目的:探讨尿铜蓝蛋白(CP)、肾损伤因子1(KIM-1)与糖尿病肾病(DKD)患者肾功能的关系及对预后不良的预测价值。方法:回顾性分析2017年1月~2019年1月陆军第八十二集团军医院肾内科收治的160例DKD患者(DKD组)的临床资料,随访3年,根据是否发展为终末期肾脏疾病(ESRD)分为预后不良组42例和预后良好组118例,另选取同期56例单纯2型糖尿病(T2DM)患者作为T2DM组和47例体检健康者作为对照组。采用微量法和酶联免疫吸附试验法检测尿CP、KIM-1水平,并计算尿白蛋白/肌酐比值(UACR)和估算肾小球滤过率(eGFR)。通过Spearman相关性分析DKD患者尿CP、KIM-1与UACR、eGFR的相关性,单因素和多因素Logistic回归分析DKD患者预后不良的影响因素,受试者工作特征(ROC)曲线分析尿CP、KIM-1对DKD患者预后不良的预测价值。结果:随访3年,160例DKD患者有42例发展为ESRD,预后不良发生率为26.25%(42/160)。DKD组尿CP、KIM-1、UACR高于T2DM组、对照组,eGFR低于T2DM组、对照组(P<0.05);T2DM组尿CP、KIM-1、UACR高于对照组,eGFR低于对照组(P<0.05)。Spearman相关性分析显示,DKD患者尿CP、KIM-1与UACR呈正相关(P均<0.001),与eGFR呈负相关(P均<0.001)。多因素Logistic回归分析显示,高血压、DKD分期4期和糖化血红蛋白(HbA1c)(较高)、低密度脂蛋白胆固醇(LDL-C)(较高)、UACR(较高)、尿CP(较高)、尿KIM-1(较高)为DKD患者预后不良的独立危险因素(P<0.05),eGFR(较高)为独立保护因素(P<0.05)。ROC曲线分析显示,尿CP、KIM-1联合预测DKD患者预后不良的曲线下面积大于各指标单独预测。结论:DKD患者尿CP、KIM-1升高与肾功能降低和预后不良密切相关,尿CP、KIM-1联合预测DKD患者预后不良的价值较高。  相似文献   
209.
摘要 目的:探讨血糖控制水平与2型糖尿病合并根尖周病的相关性。方法:回顾性选择2018年9月~2022年9月我院收治的300例2型糖尿病患者临床资料,根据是否发生根尖周病将患者分为根尖周病组(45例)和对照组(255例),根据糖化血红蛋白(HbA1c)分为血糖控制不佳组(HbA1c≥6.5%,105例),血糖控制良好组(HbA1c<6.5%,195例)。多因素Logistic回归分析2型糖尿病合并根尖周病的相关因素,受试者工作特征曲线(ROC)分析HbA1c诊断2型糖尿病合并根尖周病的价值。结果:血糖控制不佳组根尖周病发病率(28.57% vs 7.69%)、PAI评分(2.66±0.41分 vs1.24±0.26分)均高于血糖控制良好组(P<0.001)。根尖周病组吸烟史比例、牙周疾病比例、血糖控制不佳比例、FPG高于对照组(P<0.001),2型糖尿病病程长于对照组(P<0.001),服用二甲双胍比例低于对照组(P<0.01)。多因素Logistic回归结果显示血糖控制不佳、吸烟史是2型糖尿病患者合并根尖周病的危险因素(P<0.001,P<0.01),服用二甲双胍是保护因素(P<0.001)。HbA1c诊断2型糖尿病患者合并根尖周病的曲线下面积为0.659(95%CI:0.650-0.756, P<0.01),灵敏度为73.33%,特异度为62.75%,约登指数为0.3608。结论:血糖控制不佳可能与2型糖尿病患者根尖周病的发生有关,临床应积极控制血糖水平以阻止根尖周病的发生。  相似文献   
210.
摘要 目的:分析血清生长分化因子15(GDF-15)、高敏心肌肌钙蛋白T(hs-cTnT)对冠状动脉旁路移植术后新发心房颤动(房颤)及近期主要心血管事件的预测效能。方法:选择自2020年1月至2022年1月在我院行冠状动脉旁路移植术的140例冠心病患者作为研究对象,根据术后是否新发房颤,分为房颤组(46例)和非房颤组(94例)。检测两组术前血清GDF-15、hs-cTnT水平,使用多因素Logistic回归分析血清GDF-15、hs-cTnT与术后新发房颤的关系;随访6个月,观察主要心血管事件发生情况,通过受试者工作特征曲线下面积(AUC)评价血清GDF-15、hs-cTnT对术后新发房颤及近期主要心血管事件的预测效能。结果:两组患者年龄、性别、体重指数等一般资料比较无差异(P>0.05);房颤组SYNTAX积分高于非房颤组,差异有统计学意义(P<0.05);房颤组血清GDF-15、hs-cTnT水平均高于非房颤组(P<0.05);经多因素Logistic回归分析,SYNTAX积分、血清GDF-15、hs-cTnT均是冠状动脉旁路移植术后新发房颤的独立预测因素(P<0.05);经ROC曲线分析,血清GDF-15联合hs-cTnT预测冠状动脉旁路移植术后新发房颤的AUC为0.933,大于SYNTAX积分的0.790,预测近期主要心血管事件的AUC为0.925,大于SYNTAX积分的0.750(P<0.05)。结论:血清GDF-15联合hs-cTnT对冠状动脉旁路移植术后新发房颤及近期主要心血管事件均具有良好的预测效能,值得临床予以重视。  相似文献   
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