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。     

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.     

“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%。     

Fine structure of the body wall,nervous system,and digestive tract in the Lobatocerebridae Rieger and the organization of the gliointerstitial system in Annelida

The new family Lobatocerebridae, Rieger, contains a group of turbellariomorph worms in the annelid line of evolution. The fine structural organization of the body wall, the digestive tract, and parts of the central and peripheral nervous system are described and the findings are discussed in light of general invertebrate cytology. The epidermis and gastrodermis contain a basal granule cell system which is structurally very similar to the neuroglia cell system of the nervous system. The continuity of the neuroglia cell system, and the epidermal basal granule cell system and the basal granule cell system in the digestive epithelia suggests the existence of a single glial-basal granule cell system, similar to the gliointerstitial cell system first recognized in the Mollusca (see Nicaise, '73). The Annelida may show a dual (ectodermal and mesodermal) origin of such a gliointerstitial cell system as suggested by similarities in the epidermal basal cell system in the Oligochaeta and of certain epidermal and gastrodermal cells in polychaete regeneration with neuroglia in the Annelida. The structural similarity of neuroglia and basal granule cells in Lobatocerebridae may be the result of similarity in the formation, maintenance, or regulation of the extracellular matrix.     

草原鼢鼠土丘与不同根系类型植物的关系

本研究于2013-2015年的5月（春季）和9月（秋季）,在锡林浩特市南部白银库伦牧场的天然草地监测草原鼢鼠（Myospalax aspalax）生境中植被情况及新旧土丘数量,采用偏冗余分析的方法研究了新旧土丘数量与植物地上生物量的干重、株丛数和物种数之间的关系。结果表明：5月鼢鼠新土丘数量与轴根型、根蘖型植物呈正相关且具有较大解释量。鼢鼠旧土丘数量与疏丛型植物呈正相关,与轴根型和根蘖型植物呈负相关,且具有较大解释量。9月鼢鼠新土丘数量与疏丛型、密丛型和根蘖型植物呈正相关且解释量较大。鼢鼠旧土丘与疏丛型、密丛型和根蘖型植物呈正相关且解释量较大。这些结果说明草原鼢鼠的造丘活动和微栖息地选择和食物资源有关,存在季节差异。轴根型和根蘖型植物对鼢鼠的春季活动有重要影响;疏丛型、密丛型和根蘖型植物对鼢鼠的秋季活动有重要影响。     

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.     

The blood vascular system in the head of the herring gull (Larus argentatus)

The structure and development of the blood vascular system in the head of the herring gull (Larus argentatus) have been studied using injection techniques and histological sections. Three different but interconnected divisions of the arterial system are recognized in the adult: the cerebral carotid artery system, the external ophthalmic artery system, and the external carotid artery system. Embryologically, the arterial system is characterized by changes in the relative development of these three divisions; the cerebral carotid system being the most prominent in the first half of the embryonic period. The venous system is divided into two parts, the rostral cephalic system and the caudal cephalic system, which drain separate regions of the head. The Rete ophthalmicum, which is an arteriovenous network associated with the external ophthalmic artery system, can be identified from the fifth day of incubation, and its development appears to be coupled with changes in the arterial supply to the eye. The possibility of a homology between the Rete ophthalmicum of birds and the Rete caroticum of mammals is briefly discussed.     

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。     

国家重点生态功能区生态-经济-社会系统耦合协调的动态演化——以新疆阿勒泰地区为例

探究国家重点生态功能区生态-经济-社会系统耦合协调的演化特征,对实现可持续发展目标、建设美丽中国有重要意义。运用耦合协调模型、剪刀差方法、耦合度模型以及VAR模型对2007—2019年阿勒泰地区EES系统耦合协调度的动态演化进行分析。结果表明：(1)2007—2019年阿勒泰地区整体耦合协调度呈现不断上升趋势,由2007年的中度失调(0.271)向2019年的轻度失调(0.371)演进,生态系统与经济系统、社会系统的发展水平呈现“X”型变动趋势,经济系统与社会系统持续上升,而生态系统略微下降。(2)经济系统与社会系统、生态系统与社会系统演化速率的剪刀差在2014年以后出现较大幅度的波动,而生态系统与经济系统演化速率的剪刀差趋于稳定态势,生态系统与经济系统、经济系统与社会系统的耦合度呈现出由无序到有序的初始过渡。(3)由脉冲响应函数及方差分解可得,阿勒泰地区EES系统耦合协调水平的提升是三系统共同作用的结果,前期主要由社会系统、经济系统驱动,后期主要依赖生态系统的改善。研究表明：国家重点生态功能区应着重减轻经济系统对社会系统和生态系统的胁迫强度,进而实现三者的协同发展。     

A Switching Controller System for a Wheeled Mobile Robot

A wheeled mobile mechanism with a passive and/or active linkage mechanism for rough terrain environment is developed and evaluated. The wheeled mobile mechanism which has high mobility in rough terrain needs sophisticated system to adapt various environments.We focus on the development of a switching controller system for wheeled mobile robots in rough terrain. This system consists of two sub-systems: an environment recognition system using link angles and an adaptive control system. In the environment recognition system, we introduce a Self-Organizing Map (SOM) for clustering link angles. In the adaptive controllers, we introduce neural networks to calculate the inverse model of the wheeled mobile robot.The environment recognition system can recognize the environment in which the robot travels, and the adjustable controllers are tuned by experimental results for each environment. The dual sub-system switching controller system is experimentally evaluated. The system recognizes its environment and adapts by switching the adjustable controllers. This system demonstrates superior performance to a well-tuned single PID controller.     

Escherichia coli K-12 mutants that allow transport of maltose via the beta-galactoside transport system.

We have isolated mutants of Escherichia coli that have an altered beta-galactoside transport system. This altered transport system is able to transport a sugar, maltose, that the wild-type beta-galactoside transport system is unable to transport. The mutation that alters the specificity of the transport system is in the lacY gene, and we refer to the allele as lacYmal. The lacYmal allele was detected originally in strains in which the lac genes were fused to the malF gene. Thus, as a result of gene fusion and isolation of the lacYmal mutation, a new transport system was evolved with regulatory properties and specificity similar to those of the original maltose transport system. Maltose transport via the lacYmal gene product is independent of all of the normal maltose transport system components. The altered transport system shows a higher affinity than the wild-type transport system for two normal substrates of the beta-galactoside transport system, thiomethyl-beta-D-galactoside and o-nitrophenyl-beta-D-galactoside.     

A STUDY OF THE T SYSTEM IN RAT HEART

The technique of extracellular space tracing with horseradish peroxidase is adapted for labeling the transverse tubular system (T system) in rat heart. In rat ventricular muscle the T system shows extensive branching and remarkable tortuosity. The T system can only be defined operationally, since it does not display specific morphological features throughout its entire structure. Owing to branching of the T system, a sizable proportion of the apposition between the T system and L system (or closed system) occurs at the level of longitudinal branches of the T system and is not restricted to the Z line region. The regions of apposition between the T system and L system are analyzed in rat ventricular muscle and skeletal muscle (diaphragm) and compared with the intercellular tight junctions (nexuses) of heart muscle by the use of a photometric method. The over-all thickness of the nexus is significantly smaller than that of T-L junctions in both cardiac and skeletal muscles. The thickness of the membranes of the T and L systems are not significantly different in the two muscles, but the gap between both membranes is larger in the heart. In atrial muscle the following two types of cells are found: (a) those cells with a well-developed T system in which the tubular diameter is quite uniform and the orientation predominantly longitudinal and, (b) cells with no T system, but with a well-developed L system. Atrial cells possessing a T system are richly provided with specific granules and show little micropinocytotic activity, whereas cells devoid of T system show intense micropinocytotic activity and few specific granules. The possible functional implications of these findings are discussed.     

内源性大麻素系统与神经保护浅识

内源性大麻素系统包括大麻素受体、内源性配体以及参与其合成与降解的酶类,在人体内广泛分布,参与诸多生理和病理生理过程。新近报道内源性大麻素系统在中枢神经系统的许多疾病的病理生理过程中扮演重要的角色。对内源性大麻素系统的研究,不仅能阐明一些疾病的病理生理机制,还有助于新药研发并为疾病治疗提供新的方向。本文基于现有的文献报道,就内源性大麻素系统及其在一些中枢神经疾病特别是脑缺血和帕金森病的发病机制的新进展进行综述。     

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。     

Activation of human brain galactosylceramidase by phosphatidylserine.

Assays of sphingolipid hydrolases in vitro generally require bile salts or other detergents. A few 'activator proteins' have been reported that can partially replace the detergents in the assay mixture. We report here that phosphatidylserine from bovine brain is a relatively specific activator of human brain galactosylceramidase in the absence of sodium taurocholate (phosphatidylserine system). Activity similar to that obtained with the conventional assay system containing taurocholate and oleic acid (taurocholate system) could be obtained. Other lipids tested generally gave less than 10% of the taurocholate system activity, but sulfatide could activate human brain galactosylceramidase to 20--30% of the taurocholate system. The properties of the reaction in the phosphatidylserine system were examined with human brain whole homogenate, crude soluble post-concanavalin A preparations, and partially purified preparations as the enzyme source and compared with those obtained with the taurocholate system. The pH optimum shifted from 4.2 in the taurocholate system to 4.7 in the phosphatidylserine system. The phosphatidylserine system was superior in the linearity of the reaction with respect to the enzyme protein. Reasonably linear Lineweaver-Burk plots could be obtained. The Km values for the phosphatidylserine system were greater than those for the taurocholate system. The effect of phosphatidylserine was not additive to that of taurocholate. Additional phosphatidylserine to the taurocholate system was either without effect at lower concentrations or inhibitory at higher concentrations. The assays of galactosylceramidase with phosphatidylserine and without taurocholate do not necessarily provide pragmatic advantages but offer a potentially useful system with which to study the mechanism of in vivo degradation of the membrane-bound glycosphingolipid.     

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。     

Anaerobic fumarate transport in Escherichia coli by an fnr-dependent dicarboxylate uptake system which is different from the aerobic dicarboxylate uptake system.

Escherichia coli grown anaerobically with fumarate as electron acceptor is able to take up C4-dicarboxylates by a specific transport system. The system differs in all tested parameters from the known aerobic C4-dicarboxylate transporter. The anaerobic transport system shows higher transport rates (95 mumol/g [dry weight] per min versus 30 mumol/g/min) and higher Kms (400 versus 30 microM) for fumarate than for the aerobic system. Mutants lacking the aerobic dicarboxylate uptake system are able to grow anaerobically at the expense of fumarate respiration and transport dicarboxylates with wild-type rates after anaerobic but not after aerobic growth. Transport by the anaerobic system is stimulated by preloading the bacteria with dicarboxylates. The anaerobic transport system catalyzes homologous and heterologous antiport of dicarboxylates, whereas the aerobic system operates only in the unidirectional mode. The anaerobic antiport is measurable only in anaerobically grown bacteria with fnr+ backgrounds. Additionally, the system is inhibited by incubation of resting bacteria with physiological electron acceptors such as O2, nitrate, dimethyl sulfoxide, and fumarate. The inhibition is reversed by the presence of reducing agents. It is suggested that the physiological role of the system is a fumarate/succinate antiport under conditions of fumarate respiration.