Respiratory Variations in Arterial Blood Pressure and Heart Rate in Normotensive and Renal Hypertensive Dogs

Respiratory sinus arrhythmia (RSA), systolic and diastolic respiratory blood pressure waves (RBPWsyst, RBPWdiast), mean heart rate (HR), mean respiratory frequency (RF) and the heart beat to respiratory cycle ratio (HB/RC) were measured in 23 spontaneously breathing, normotensive or renal hypertensive dogs under light anaesthesia. No significant differences were found between conditions of normal and chronically elevated blood pressure. All these parameters were analyzed statistically by means of linear regression analysis and rank correlation coefficient (rs). A correlation was found to exist between RSA and mean systolic blood pressure (negative), RF (negative), RBPWsyst (positive), RBPWdiast (positive). RF correlated with both HB/RC (negative) and RBPWsyst (negative). A correlation was also seen between PA and both BPsyst (positive) and BPdiast (positive), BPsyst and BPdiast (positive) and between HR and RBPWdiast (negative); however, all the remaining, theoretically possible correlations were not significant. The results may be referred to resonance mechanisms in a common nervous oscillator system.     

飞行任务中分心物的速度与数量变化对手眼协调追踪绩效的影响

目的通过比较不同任务条件下的持续追踪时间,考察在多目标追踪范式下个体的手眼协调追踪绩效。方法采用多目标追踪的变式,志愿者用鼠标操控红色方块—飞机,躲避运动的若干蓝色方块—干扰物,飞机碰触到干扰物或灰色边界,任务结束,记录志愿者的持续追踪时间。结果志愿者的手眼协调追踪绩效受到干扰物速度和数量的影响。当运动速度加快或干扰物数量增加,持续追踪时间下降。结论手眼协调绩效受到干扰物速度和数量的影响,速度和干扰物数量的增加使追踪成绩直线下降。     

Arm load magnitude affects selective shoulder muscle activation

For isometric tasks, shoulder muscle forces are assumed to scale linearly with the external arm load magnitude, i.e., muscle force ratios are constant. Inverse dynamic modeling generally predicts such linear scaling behavior, with a critical role for the arbitrary load sharing criteria, i.e., the “cost function”. We tested the linearity of the relation between external load magnitude exerted on the humerus and shoulder muscle activation. Six isometric force levels ranging from 17 to 100% of maximal arm force were exerted in 24 directions in a plane perpendicular to the longitudinal axis of the humerus. The direction of maximum muscle activation, the experimentally observed so called Principal Action (PA), was determined for each force magnitude in 12 healthy subjects. This experiment was also simulated with the Delft Shoulder and Elbow Model (DSEM) using two cost functions: (1) minimizing muscle stress and (2) a compound, energy related cost function. PA, both experimental (PA_exp) and simulated (PA_sim), was expected not to change with arm forces magnitudes. PA_exp of the mm. trapezius pars descendens, deltoideus pars medialis and teres major changed substantially as a function of external force magnitude, indicating external load dependency of shoulder muscle activation. In DSEM simulations, using the stress cost function, small non-linearities in the muscle force–external load dependency were observed, originating from gravitational forces working on clavicular and scapular bone masses. More pronounced non-linearities were introduced by using the compound energy related cost function, but no similarity was observed between PA_exp and PA_sim.     

小儿脊髓拴系综合征显微手术的护理

目的：探讨小儿脊髓拴系综合征显微手术的术中护理要点。方法：回顾2005年11月～2007年2月在显微镜下治疗脊髓拴系综合征的手术期护理记录,总结手术期间的护理要点。结果：47例患儿均在显微镜下行脊髓拴系松解术,手术全部成功,无术中并发症发生。结论：要保证手术顺利进行,必须注意以下几点：（1）术前正确的体位摆放;（2）充分的器械、物品准备;（3）保证显微器械的正常使用;（4）细致的病情观察和密切的护理配合。     

儿童发育性运动协调障碍与注意缺陷多动障碍的关系研究

目的探讨注意缺陷多动障碍与发育性运动协调障碍之间的关系。方法对我院门诊的60例注意缺陷多动障碍患儿进行评估,以发育性运动协调问卷（DCDQ）评定发育性运动协调问题。结果注意缺陷多动障碍患儿DCDQ得分低于正常儿童,差别具有显著性意义（P〈0.01）。注意缺陷多动障碍患儿中20.0%同时存在发育性运动协调障碍,33.3%为可疑发育性运动协调障碍。其中25.0%的注意缺陷型、20.0%的多动-冲动型和22.2%的混合型注意缺陷多动障碍患儿同时存在发育性运动协调障碍,三种亚型与发育性运动协调障碍的共病率间差别无显著性意义（P〉0.05）。结论注意缺陷多动障碍与发育性运动协调障碍密切相关,且注意缺陷多动障碍的三种亚型与发育性运动协调障碍均存在共病,这为注意缺陷多动障碍的治疗提供了新思路。     

Influence of arm movements on saccades in humans

When reaching for an object we usually look at it before we touch it with the hand. This often unconscious eye movement prior to the arm movement allows guiding of the final part of the hand trajectory by visual feedback. We examined the temporal and spatial coordination of this control system by psychophysical measurements of eye and arm movements of naive human subjects looking or looking and pointing as fast as possible to visual targets in physical and virtual-reality setups. The reaction times of saccades to a step-displaced target were reduced, and the number of corrective saccades decreased, when the subject had to produce a corresponding simultaneous hand movement to the same target. The saccadic reaction time was increased when saccade and hand movement went in opposite directions. In a double-step task the reaction time for the second saccade was longer than for the first. Co-use of the hand leads to an additional increase of saccadic reaction time. Taken together this study shows an improvement in initial saccades if they are accompanied by hand movements to the same target. This effect might ensure that the reach target is foveated early and accurately enough to support the visual feedback control of the hand near the target. Longer reaction times for the second saccade to double-step displaced targets might reflect a saccadic refractory time intensified by simultaneous arm movements. These results are discussed in the light of recent findings from our laboratory on saccade- and reach-related neurons in the superior colliculus of macaque monkeys.     

中药配位化学研究进展

从中药毒理学和药理学、中药功效成分的改进以及中药功效成分的分离制备和鉴定3个方面论述了中药配位学说在中药研究领域中的重要意义,并列举了中药配位研究领域常用的技术。指出中药配位热力学和动力学的研究、中药中微量元素的存在状态与药效和毒性关系的研究、利用配位作用开发高效分离吸附剂或者高效分离色谱柱、利用有机成分与某些金属或微量元素生成有色配合物的特性开发高灵敏度的分析方法可能成为中药现代化研究过程中的热点和关键。     

Hypoglossal and reticular interneurons involved in oro-facial coordination in the rat

Chewing, swallowing, breathing, and vocalization in mammals require precise coordination of tongue movements with concomitant activities of the mimetic muscles. The neuroanatomic basis for this oro-facial coordination is not yet fully understood. After the stereotaxic microinjection of retrograde and anterograde neuronal tracers (biotin-dextran, Fluoro-Ruby, Fluoro-Emerald, and Fluoro-Gold) into the facial and hypoglossal nuclei of the rat, we report here a direct bilateral projection of hypoglossal internuclear interneurons onto facial motoneurons. We also confirm the existence of a small pool of neurons in the dorsal part of the brainstem reticular formation that project ipsilaterally to both facial and hypoglossal nuclei. For precise tracer injections, both motor nuclei were located and identified by the electrical antidromic activation of their constituent motoneurons. Injections of retrograde tracers into the facial nucleus consistently labeled neurons in the hypoglossal nucleus. These neurons prevalently lay in the ipsilateral side, were small in size, and, like classic intrinsic hypoglossal local-circuit interneurons, had several thin dendrites. Reverse experiments - injections of anterograde tracers into the hypoglossal nucleus - labeled fine varicose nerve fiber terminals in the facial nucleus. These fiber terminals were concentrated in the intermediate subdivision of the facial nucleus, with a strong ipsilateral prevalence. Double injections of different tracers into the facial and the hypoglossal nuclei revealed a small, but constant, number of double-labeled neurons located predominantly ipsilateral in the caudal brainstem reticular formation. Hypoglossal internuclear interneurons projecting to the facial nucleus, as well as those neurons of the parvocellular reticular formation that project to both facial and hypoglossal nuclei, could be involved in oro-facial coordination.     

Deficits in attention, motor control and perception (DAMP): a simplified school entry examination

OBJECTIVE: To suggest an empirically based school entry screening examination for the detection of deficits in attention, motor control and perception (DAMP) in 6-y-old children. MATERIAL AND METHODS: A population-based cohort of 113 children, 6-7 y of age (62 with and 51 without DAMP), compared on measures of attention, motor functions, language and cognition. RESULTS: Attention deficits were convincingly identified by both parents and paediatrician. The motor function tests clearly distinguished between the two groups. Linguistic and meta-linguistic tests demonstrated greater phonological processing difficulties in the DAMP group. The cognitive test revealed an overall lower IQ but no consistent characteristic pattern in the DAMP group. CONCLUSIONS: A simplified paediatric school entry examination test is suggested. Four motor tests (standing on one foot, Fog test, design copying and diadochokinesis) administered by the paediatrician, combined with a brief structured clinical observation and a structured parent interview, identified 80% of children with DAMP-and all those with severe DAMP-as well as a small number of false positives.     

Polymerization of 4‐Methyl‐1,3‐pentadiene with Catalysts Based on Cyclopentadienyl Titanium Chlorides: Effect of anti/syn Isomerism of the Allylic Group on the Chemoselectivity and the Role of Backbiting Coordination in 1,3‐Diene Polymerization

Summary: Homopolymerization of 4‐methyl‐1,3‐pentadiene (MP) and copolymerization of 4‐methyl‐1,3‐pentadiene with alkenes (ethylene, 1‐pentene, 4‐methyl‐1‐pentene) were performed to investigate the effect of the so‐called backbiting coordination on the chemoselectivity of 1,3‐diene polymerization. Three homogeneous catalyst systems were used: CpTiCl₃‐MAO, Cp₂TiCl₂‐MAO and Cp₂TiCl‐MAO. Backbiting coordination is possible with the first catalyst, but not with the other two. The three catalysts gave similar results, which indicates that backbiting has no effect on the polymerization chemoselectivity, contrary to what has been reported in recent literature. An interpretation is presented for the formation of 1,4 units in MP/alkene copolymers. This interpretation is based on the fact that allyl groups have predominantly a syn configuration in MP homopolymerization, whereas allyl groups of anti configuration are formed in MP/alkene copolymerization. The role of backbiting in diene polymerization is discussed.

The effect of anti/syn isomerism on the chemoselectivity in the different polymerizations.