简介:摘要:力标准机作为比较稳定的计量设备,拥有使用寿命长的特点,所以现有的大多数力标准机产于上世纪60年代~80年代。其控制系统老旧,可靠性不高。针对这一国内普遍存在的问题,本文提供了一种基于西门子PLC的控制系统设计方案,通过对力标准机结构的分析,针对其运行特点,选用适当的人机交换硬件,建立以太网或RS485通讯,从而建立一条从人机界面——PLC——电机的控制链,实现对力标准机的手动和自动控制。
简介:摘要:在某些行业的粉料或颗粒料半自动包装设备中,生产出来的产品通常都用编织袋来包装,在编织袋缝口的时候传统操作都需要人工用手放置一个标签,跟随缝包机缝合在袋口上,在现有的技术中,人工在缝口的时候手动放置标签,不仅存在人员的安全隐患,而且费时费力,严重影响生产效率。
简介:AbstractObjective:To characterize and compare the microbiome signature in the maternal, intrauterine, and fetal environments and the associated bacterial species in women who experienced preterm birth and term birth.Methods:A total of 140 women with singleton pregnancies were enrolled in this study. Among them, 31 experienced spontaneous preterm delivery (gestational age < 37 weeks), and 28 of them experienced vaginal delivery at term. Maternal peripheral blood, saliva, and vaginal discharge samples and fetal membrane, amniotic fluid, and cord blood samples were collected immediately after delivery under sterile conditions. DNA was isolated from the fetal membrane and umbilical cord blood samples, and the V3-V4 region of the bacterial 16S rRNA gene was sequenced. The sequence data were quality-filtered, chimera-checked, and organized into operational taxonomic units (OTUs) based on phylogeny. Principal coordinate analysis of beta diversity measures was used for visualization. The linear discriminant analysis effect size (LEfSe) algorithm and Wilcoxon test were used to differentiate the microbiomes found in the fetal membranes and cord blood in the cases of preterm birth.Results:OTU analysis based on the 16S rRNA gene showed similar microbiomes in the maternal peripheral blood, amniotic fluid, fetal membranes, and cord blood. However, the LEfSe algorithm revealed significantly different bacterial compositions in the fetal environment between the preterm and term groups, with some of the bacterial species originating from the maternal peripheral blood or saliva.Conclusions:The bacteria in the intrauterine and fetal environments may originate from other body sites through hematogenous transmission, and may cause the occurrence of preterm birth.
简介:摘要:为提高精子库工作人员精子库信息管理工作效率,解决精子库数据记录不全、现有系统扩展性差等问题,本文构建了基于B/S架构的精子库信息管理系统,该系统可为采集部门、冷冻部门、供给部门及档案管理部门工作人员提供捐精者管理、档案管理、精液质量控制、精液管理、供精管理以及统计管理等功能,实现精子库业务流程的信息化管理。
简介:摘要目的探讨不同部位症状性Rathke's囊肿(RCC)手术方式的选择及临床疗效。方法选择广东三九脑科医院神经外科自2016年1月至2019年12月和手术治疗的47例症状性RCC患者进入研究,其中21例单纯鞍内型患者行右侧单鼻孔入路,19例鞍内-鞍上型患者行双侧鼻孔入路,3例鞍上型患者采用内镜扩大经鼻蝶入路,4例单纯鞍上型患者采用开颅经翼点入路。比较不同手术方式治疗患者疗效及并发症发生情况。所有患者随访3~36个月,观察复发情况。结果患者术后症状得到有效改善,其中头痛缓解比例为27/31,视力下降改善比例为5/5,高泌乳素缓解比例为11/13,垂体功能改善比例为9/18;共6例患者出现并发症,均表现为尿崩。随访期间4例患者出现复发。结论鞍内型及鞍内-鞍上型RCC经鼻蝶入路行内镜治疗安全有效,单纯鞍上型RCC应根据囊肿体积及生长方向选择手术方式。