生物体微弱磁场检测技术在某部特殊作业人员健康评估中的应用研究

目的:研究某部特殊作业人员的健康状况,为有针对性地提出防护措施提供参考依据。方法:随机抽取某部不同工作岗位的特殊作业人员145名,进行生物体微弱磁场检测分析,以获取包括疲劳、免疫、睡眠、脑机能、血压、心脏、消化、肝胆、泌尿生殖、呼吸、运动、钙代谢、糖代谢、脂代谢、嘌呤代谢等15个系统在内的108项健康评估检测指标。对于每一项指标,仪器自带有其正常值范围,凡低于下限或高于上限的指标被视为异常。结果:所测特殊作业人员总体在钙代谢系统、消化系统、心脏系统、血压系统、呼吸系统、运动系统、免疫系统等七个系统存在不适症状的较为突出,其中钙代谢失衡的占比83.45%,脾胃不和的占比78.62%,心脏功能欠佳的占比72.41%,血压不稳的占比64.14%,咽喉不适的占比59.31%,骨关节不适的占比58.62%,免疫功能下降的占比51.72%。出现运动系统"颈椎疾患"症状的人数占比,实验组明显高于对照组(P0.05)。结论:特殊作业环境可能会影响作业人员的身体健康,应采取有效的安全防护措施,以减弱或消除有毒有害化学物质污染、强噪声、电磁辐射等对人体健康的影响。     

Modulation of dynamic parameters of muscle reflex by selective activation of its gamma system

The ability of the gamma system to modify the dynamics of the muscle reflex control system is investigated. The dynamics of the triceps surae muscle in decerebrate cat preparations with intact reflex loops were modulated by contralateral tibial and peroneal nerve stimulation. The parameters of the mathematical models representing the muscle reflex system were estimated by the least squares method. The behaviour of the mathematical models of the system, under various degrees of gamma system stimulation, was then studied in response to disturbance inputs. It is shown that the gamma motor system is an efficient agent for carrying out modifications in the dynamics of the muscle reflex system. The possible functional significance of this phenomenon within the framework of operation of the muscular control system is discussed with reference to optimal adaptive system concepts.     

Evaluation of Radiometric System for Detecting Bacteremia

An automated radiometric system (BACTEC, Johnston Laboratories) for detection of bacteremia was evaluated in parallel with a standard blood culture system in use in our laboratory. Of 1,445 blood cultures from 484 patients with possible bacteremia, 106 sets of cultures (excluding 39 presumed contaminated), representing 56 patients, were positive by both methods. The conventional system yielded 85 positive cultures from 48 patients, whereas the BACTEC system yielded 84 positive cultures from 43 patients. The BACTEC system failed to detect 22 cultures that were positive in the conventional system, and the conventional system failed to detect 21 cultures that were positive in the BACTEC system. The detection efficiency was generally equivalent in the two systems except for the lower detection rates of anaerobes and Enterobacter aerogenes by the BACTEC system and the lower detection rates of Torulopsis glabrata and, possibly, Pseudomonas sp. (group IVD) in the conventional system. The BACTEC system had a slight advantage over the conventional system in the time interval to detection of positivity. Approximately 20% of the positive cultures detected by the BACTEC system were detected on the first day of incubation compared with 7% by the conventional system. The recovery rates and detection times of anaerobes were less efficient by the BACTEC system than by the conventional system. It does not appear that the radiometric method has much advantage over available conventional methods.     

河西走廊山地-绿洲-荒漠复合系统耦合的景观生态学机制

系统耦合的基础为非生物环境的空间异质性,基本条件为具有类型相同并且相互连通的廓道,系统耦合的景观生态学机制为非生物环境的空间分异和各种干扰导致的景观异质化,各种干扰是系统耦合的介质,系统耦合从本质上可以被看作尺度变大过程中景观组分的融合与性质转换的过程,系统耦合根据干扰的性质可以分为自然耦合和人为耦合2类,自然耦合是人为耦合的基础,系统生态生产力的提高取决于人为耦合的优化过程。     

制度供给视角下的基本医疗体制改革之决策

基本医疗改革的财政投入模式应从单一关注医疗服务供给转向协同关注医疗服务产出，无过错医疗损害救济应纳入国家财政投入的预算体系。面对医疗损害的高发性，以救济为心的医疗侵权责任制度应向以预防中心的制度进行改革。医疗过失诉讼制度对医疗体系有着深刻的负面制约作用。基本医疗改革的决策应从更宏观的视角进行制度供给设计。     

门诊预约服务体系建设中的问题与对策

门诊预约服务在政府的倡导下广泛开展,门诊预约服务体系的建设是现阶段的主要任务。预约体系包括信息系统、服务系统、管理系统和评价系统,各系统相互配合构成统一的整体。目前预约服务还面临着不少难题,对不同系统的主要问题和解决思路作一简要探讨。     

“山地-绿洲-荒漠”复合系统土地利用变化的生态系统服务权衡与协同效应——以张掖市为例

开展复合生态系统土地利用变化的生态服务效应研究可为优化国土空间格局和强化生态系统管理提供重要的基础依据。以干旱区"山地-绿洲-荒漠"复合系统的典型区域张掖市为例，基于1987年、2000年和2018年3期土地利用数据，以乡级行政区为基本单元，引入相对优势度指数划分山地、绿洲、荒漠子系统，研究复合系统的土地利用变化特征及生态系统服务权衡/协同效应。结果表明：（1）张掖市复合系统呈现地域分异特征，由南部山地系统，中部绿洲系统和北部荒漠系统构成；山地系统以林地和草地为主，绿洲系统以耕地和建设用地为主，荒漠系统以未利用地为主。（2）从时间上看，2000-2018年各系统的土地利用变化更强烈，其中，绿洲系统的耕地面积增加量最大，为363.08km²，荒漠系统的建设用地面积增加幅度最大，为78.23%。各系统土地利用转移模式为：山地系统以草地转耕地为主，绿洲系统和荒漠系统以未利用地转耕地为主。（3）张掖市复合系统的生态服务价值呈增加趋势，其中，荒漠系统生态服务价值量的增幅最大，各子系统的价值量之间的关系表现为山地系统 > 绿洲系统 > 荒漠系统，耕地对各系统生态服务价值贡献量最大。（4）张掖市土地利用变化的协同效应大于权衡效应，其中荒漠系统的生态服务之间均为协同关系，山地系统中供给服务与其他服务呈现权衡关系，占比32.73%，绿洲系统中调节服务与其他服务呈现权衡关系，占比18.18%。     

Immobilization of glycolysis system of yeasts and production of cytidine diphosphate choline

Summary Glycolysis system of yeast was successfully immobilized into a derivative of polyethylene glycol hydroxyethylacrylate. The immobilized system could produce ATP and then phosphorylate nucleotides (CMP). The CTP thus formed was effectively converted to CDP-choline in the same system (Fig.2).This system is a kind of bioreactor, consisting of energy (ATP) generating and transformation systems of various substances.     

山水林田湖草生态保护修复的系统性认知

系统治理是山水林田湖草生态保护修复的核心,然而在工程实施和评估中如何有效落实和考核山水林田湖草生态保护修复的系统性仍是目前一大难题。通过厘清系统性与整体性的逻辑关系,从山水林田湖草生态保护修复的对象、主体及其耦合联系入手,明晰系统治理是山水林田湖草生态保护修复的必然选择,进而提出关键要素控制与全要素耦合相结合的治理思路,并以云南抚仙湖项目区为例阐明系统治理在山水林田湖草生态保护修复中的实践路径。最后,依据结构-功能复杂度、要素关联紧密度及其认知,将山水林田湖草治理系统分为形态系统、级联系统、过程-响应系统、控制系统等四级递进系统,从流域内和流域外的空间视角出发,提出基于“目标-约束-成本”的山水林田湖草生态保护修复系统性评估方法,为山水林田湖草系统治理的实施与考核提供核心科学支撑。     

Optimal control mode of a biochemical feedback system

An optimal feedback system for constant-value control of biochemical reaction system was investigated by computer simulations. A feedback system containing a cyclic enzyme system where two enzyme types share a substrate in a cyclic manner, was found to be the most reliable one. This feedback system has a capability to keep the stationary value of the end product at a desired level against not only exogenous substrate supply but also endogenous parametric disturbances. The cyclic enzyme system installed as a control element of this feedback system played the role of comparator in this feedback system. The control mode of this feedback system was in good agreement with that of a system established by means of optimization technique based on the maximum principle. Also bang - bang control could be performed in this biochemical feedback system as well as in electrical one.     

部分国家和地区分级诊疗特点及启示

通过剖析部分国家和地区分级诊疗的特点,即分级诊疗是医疗卫生服务体系健全的自然结果,分级诊疗的实质在于服务整合,合理的支付制度是分级诊疗的重要促进因素;提出以强基层、建机制的原则发展分级诊疗,将医疗机构分工合作、服务功能整合作为分级诊疗的重要路径,增强医保对医疗服务体系的影响力以促进分级诊疗等建议。     

毕赤酵母蛋白表达系统研究进展

选择合适的蛋白表达系统是外源基因能否成功表达的关键.毕赤酵母(Pichia pastoris)蛋白表达系统是近些年来发展起来的一种真核表达系统,与其他表达系统相比,该系统所具有的诸多优势使其研究价值和应用价值越来越广泛,已经成功表达了多种蛋白质.简要综述其特点、表达宿主菌、表达载体以及其元件、外源蛋白的表达及其影响因素等方面的基础研究和最新进展.     

Gametogenesis of intergroup hybrids of hemiclonal frogs

European water frog hybrids Rana esculenta (R. ridibundaxR. lessonae) reproduce hemiclonally, by hybridogenesis: in the germ line they exclude the genome of one parental species and produce haploid gametes with an unrecombined genome of the other parental species. In the widespread L-E population system, both sexes of hybrids (E) coexist with R. lessonae (L). They exclude the lessonae genome and produce ridibunda gametes. In the R-E system, hybrid males coexist with R. ridibunda (R); they exclude either their ridibunda or their lessonae genome and produce sperm with a lessonae or with a ridibunda genome or a mixture of both kinds of sperm. We examined 13 male offspring, 12 of which were from crosses between L-E system and R-E system frogs. All were somatically hybrid. With one exception, they excluded the lessonae genome in the germ line and subsequently endoreduplicated the ridibunda genome. Spermatogonial metaphases contained a haploid or a diploid number of ridibunda chromosomes, identified through in situ hybridization to a satellite DNA marker, and by spermatocyte I metaphases containing a haploid number of ridibunda bivalents. The exception, an F1 hybrid between L-E system R. lessonae and R-E system R. ridibunda, was not hybridogenetic, showed no genome exclusion, and evidenced a disturbed gametogenesis resulting from the combination of two heterospecific genomes. None of the hybridogenetic hybrids showed any cell lines excluding the ridibunda genome, the pattern most frequent in hybrids of the R-E system, unique to that system, and essential for its persistence. A particular combination of R-E system lessonae and R-E system ridibunda genomes seems necessary to induce the R-E system type of hemiclonal gametogenesis.     

Long-term culturing of plants with aseptic roots Determination of rape root exudates

Abstract A plant culture system allowing growth of aseptic roots has been designed. One version of the system comprises vessels developed for plant root-microorganism interaction studies in series. A second version has been built for measurements of different physiological parameters of the shoot and root system during growth periods of at least 2 months. The system was tested by determining soluble organic carbon glucose and sucrose in the root exudates of rape plants (Brassica napus L.) grown for 3 weeks in the culture system. The plants were cultivated with a sterile or a non-sterile root system, or with a root system infected with Verticillium dahliae Kleb.     

Development of an automated flow-injection system for the determination of trace level ammonia

An in-housed designed computerised flow injection system for low level ammonia analysis is examined. The system features an on-line microdistillation preconcentration unit, which was used as an on-line sample pretreatment step in an ammonia gas-sensing probe flow injection system. A simple, low cost computerised control and data acquisition system was designed using a commercial pH meter with RS-232 interface and in-house designed control system. The system offered a practical and effective means of extending the detection limit of commercial available ammonia gas sensing probes to 5 μg/1 NH₃N.     

对建设中国特色现代医院管理制度的思考

公立医院在我国医疗卫生服务体系中承担着重要保障作用。随着改革的不断推进,社会各界对建立符合中国特色要求的现代医院管理制度的呼声日渐高涨。在对已有研究进行总结的基础上,结合各地开展公立医院改革的具体实践经验,从目前医院运营管理现状入手,逐步梳理医院管理制度建设面临的困境及存在的困难,对现代医院管理制度内涵进行梳理,探讨建立中国特色现代医院管理制度的具体实现路径。     

铅的生物学毒性效应

铅对生物体具有多方面的毒性,可导致智力低下、造血机能障碍、高血压、肾病等,其毒性机理还在探索阶段。本文主要介绍了铅对各个系统如神经系统、心血管系统、泌尿系统、生殖系统以及个体发育的毒性效应。