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81.
医疗机构实施ISO9001,其目的是为了提高医疗服务质量,满足病人一切明确和隐含的需求。那么,内审是否发挥作用,直接关系管理体系的有效性。文章对此进行了初步的探讨,即:①明确内审的目的是检查体系满足标准要求的程度;②建立正规的内审机构,要选拔责任心强、综合素质高的人担任内审员;③编制合理且有特色的内审计划,是内审有效性的关键;④适当增加专题审核;⑤医院最高管理者应重视内审结果。  相似文献   
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83.
Renal nerves play an important role in the setting of the sensitivity of the tubuloglomerular feedback (TGF) mechanism. We recently reported a time-dependent resetting of TGF to a lower sensitivity 3–4 h after acute unilateral renal denervation (aDNX). This effect persisted after 1 week, but was then less pronounced. To determine whether normal TGF sensitivity could be restored in aDNX kidneys by low-frequency renal nerve stimulation (RNS), the following experiments were performed. Rats with aDNX were prepared for micropuncture. In one experimental group proximal tubular free flow (Pt) and stop flow pressures (Psf) were measured during RNS at frequencies of 2, 4 and 6 Hz. In another series of experiments the TGF sensitivity was evaluated from the Psf responses at different loop perfusion rates after 20 min of RNS at a frequency of 2 Hz. The maximal drop in PsfPsf) and the tubular flow rate at which half the maximal response in ΔPsf was observed (turning point, TP), were recorded. At RNS frequencies of 2, 4 and 6 Hz, Pt decreased from the control level of 14.1 ± 0.8–13.1 ± 1.0, 12.4 ± 1.1 and 11.2 ± 0.8 mmHg (decrease 21%, P < 0.05), respectively, while at zero perfusion and during RNS at 2 and 4 Hz Psf decreased from 42.5 ± 1.6 to 38.2 ± 1.4 and 32.8 ± 4.3 mmHg (decrease 23%, P < 0.05), respectively. The TGF characteristics were found to be reset from the normal sensitivity with TP of 19.0 ± 1.1 nL min–1 and ΔPsf of 8.7 ± 0.9 mmHg to TP of 28.3 ± 2.4 nL min–1 (increase 49%, P < 0.05) and ΔPsf of 5.8 ± 1.2 mmHg (decrease 33%) after aDNX. After 20 min of RNS at 2 Hz TP was normalized and ΔPsf was 33% higher. Thus the present findings indicate that the resetting of the TGF sensitivity that occurred 2–3 h after aDNX could be partially restored by 20 min of RNS at a frequency of 2 Hz. These results imply that renal nerves have an important impact on the setting of the sensitivity of the TGF mechanism.  相似文献   
84.
The functional relation between receptive fields of climbing fibres projecting to the C1, C3 and Y zones and forelimb movements controlled by nucleus interpositus anterior via the rubrospinal tract were studied in cats decerebrated at the pre-collicular level. Microelectrode tracks were made through the caudal half of nucleus interpositus anterior. This part of the nucleus receives its cerebellar cortical projection from the forelimb areas of these three sagittal zones. The C3 zone has been demonstrated to consist of smaller functional units called microzones. Natural stimulation of the forelimb skin evoked positive field potentials in the nucleus. These potentials have previously been shown to be generated by climbing fibre-activated Purkinje cells and were mapped at each nuclear site, to establish the climbing fibre receptive fields of the afferent microzones. The forelimb movement evoked by microstimulation at the same site was then studied. The movements usually involved more than one limb segment. Shoulder retraction and elbow flexion were frequently evoked, whereas elbow extension was rare and shoulder protraction never observed. In total, movements at the shoulder and/or elbow occurred for 96% of the interpositus sites. At the wrist, flexion and extension movements caused by muscles with radial, central or ulnar insertions on the paw were all relatively common. Pure supination and pronation movements were also observed. Movements of the digits consisted mainly of dorsal flexion of central or ulnar digits. A comparison of climbing fibre receptive fields and associated movements for a total of 110 nuclear sites indicated a general specificity of the input-output relationship of this cerebellar control system. Several findings suggested that the movement evoked from a particular site would act to withdraw the area of the skin corresponding to the climbing fibre receptive field of the afferent microzones. For example, sites with receptive fields on the dorsum of the paw were frequently associated with palmar flexion at the wrist, whereas sites with receptive fields on the ventral side of the paw and forearm were associated with dorsiflexion at the wrist. Correspondingly, receptive fields on the lateral side of the forearm and paw were often associated with flexion at the elbow, whereas sites with receptive fields on the radial side of the forearm were associated with elbow extension. The proximal movements that were frequently observed also for distal receptive fields may serve to produce a general shortening of the limb to enhance efficiency of the withdrawal. It has previously been suggested that the cerebellar control of forelimb movements via the rubrospinal tract has a modular organisation. Each module would consist of a cell group in the nucleus interpositus anterior and its afferent microzones in the C1, C3 and Y zones, characterised by a homogenous set of climbing fibre receptive fields. The results of the present study support this organisational principle, and suggest that the efferent action of a module is to withdraw the receptive field from an external stimulus. Possible functional interpretations of the action of this system during explorative and reaching movements are discussed.  相似文献   
85.
Summary Oculomotor response has been assessed in humans during the presentation of conflicting retinal motion stimuli. In the majority of experiments a background stimulus was made to move with a constant velocity ramp in one direction followed by rapid resets at regular intervals. In the absence of an adequate fixation target this ramp-reset stimulus induced a nystagmus with a slow-phase velocity and saccadic frequency which remained almost constant as reset frequency was increased from 2 to 5 Hz. Moreover, the induced eye velocity could be considerably increased if the subject attempted active matching of display velocity. During both active and passive responses eye velocity gain reached a peak when display velocity was between 2°/s and 5°/s. The presence of small stationary targets induced a suppression of the passive ramp-reset response which was modified by target eccentricity and by tachistoscopic target illumination. When subjects pursued a sinusoidally oscillating target against a stationary structured background, eye velocity gain was significantly less than for pursuit against a blank background. The degree of interaction between conflicting stimuli was found to be dependent on their relative size, peripheral location and velocity. However, it appears that the human observer is able selectively to enhance feedback gain from one particular source in order to dominate stimuli from other unwanted sources.  相似文献   
86.
M Ennis  F L Pearce  C A Vernon 《Neuroscience》1979,4(9):1391-1398
The effects of antibodies to the nerve growth factor from mouse salivary gland were examined in vitro and in vivo. Treatment of explants of receptive ganglia with antibody and complement did not produce cell damage as judged by the ability of the tissue to respond to nerve growth factor. New-born mice experimentally depleted of or genetically deficient in key complement components were susceptible to the action of the antiserum.These results show that the effect of the antibody is independent of complement and are consistent with the view that it acts by neutralization of endogenous nerve growth factor.  相似文献   
87.
Lateralized rewarding brain stimulation affects forepaw preference in rats   总被引:1,自引:0,他引:1  
Rats trained to reach for food pellets into a narrow tubular feeder consistently prefer to perform this stereotype instrumental movement with either the left or right forepaw. In 16 rats with established handedness electrodes were implanted into both lateral hypothalami. The animals were rewarded by intracranial self stimulation (ICSS, 300 msec, 50 Hz, 20-60 microA) for reaching into a modified feeder for a plastic ball operandum, the movement of which between the bottom and entrance of the feeder was monitored by mechanical contacts. The rats readily continued to reach when ICSS was delivered immediately after the photoelectrically detected reach or after the displacement of the operandum. Most rats learned in a single session to modify the movement when ICSS delivery was made contingent upon holding the operandum between the bottom and entrance of the feeder for 256 or 512 msec. The efficiency of reaching (ratio of successful reaches to all reaches) decreased with increasing holding time; only a few animals were able to master a 1024 msec delay. Reaching was supported by ICSS of either lateral hypothalamus. Whereas in 8 rats the strongly expressed forepaw preference was not changed by lateralized ICSS, in 8 latently ambidextrous animals stimulation of the lateral hypothalamus ipsilateral to the preferred forepaw increased reaching with the normally non-preferred forepaw from 15% to 60%. Stimulation of the lateral hypothalamus contralateral to the preferred forepaw did not change the preference. The preference shift was equally well expressed in simple and difficult versions of the task. It is concluded that lateralization of motivational influences can be reflected in the asymmetry of the neural mechanisms processing the lateralized sensory signals and/or elaborating the lateralized motor output.  相似文献   
88.
 Although it is obvious that vision plays a primary role in reaching and grasping objects, the sources of the visual information used in programming and controlling various aspects of these movements is still being investigated. One source of visual information is feedback relating to the characteristics of the reach itself – for example, the speed and trajectory of the moving limb and the change in the posture of the hand and fingers. The present study selectively eliminated this source of visual information by blocking the subject’s view of the reaching limb with an opaque barrier while still enabling subjects to view the goal object. Thus, a direct comparison was made between standard (closed-loop) and object-only (open-loop) visual-feedback conditions in a situation in which the light levels and contrast between an object and its surroundings were equivalent in both viewing conditions. Reach duration was longer with proportionate increases in both the acceleration and deceleration phases when visual feedback of the reaching limb was prevented. Maximum grip aperture and the proportion of movement time at which it occurred were the same in both conditions. Thus, in contrast to previous studies that did not employ constant light levels across closed- and open-loop reaching conditions, a dissociation was found between the spatial and temporal dimensions of grip formation. It appears that the posture of the hand can be programmed without visual feedback of the hand – presumably via a combination of visual information about the goal object and proprioceptive feedback (and/or efference copy). Nevertheless, maximum grip aperture (like the kinematic markers examined in the transport component) was also delayed when visual feedback of the reaching limb was selectively prevented. In other words, the relative timing of kinematic events was essentially unchanged, reflecting perhaps a tight coupling between the transport and grip components. Received: 3 July 1998 / Accepted: 18 November 1998  相似文献   
89.
目的调查本地某乡镇一次麻疹疫情的流行强度,描述其三间分布,分析暴发原因及影响因素。方法现场流行病学调查,酶联免疫捕获法检测麻疹IgM抗体,作免疫空白与麻疹发病关联的病例对照研究。结果2006年5月~7月,该乡镇发生30例麻疹局部暴发,其中29例儿童麻疹,1例成人麻疹,5例麻疹IgM抗体阳性。发病地点主要为小学和和幼儿园,罹患率分别为7.94%、7.87%。免疫空白与发病关系研究表明,初种免疫空白OR=7.2,X2=6.84,复种免疫空白OR=11.0,X2=9.48;影响免疫空白形成的社会因素调查,未接受麻疹疫苗初种或复种儿童的父母双亲常年在外务工占82.4%(28/34),有麻疹疫苗接种史儿童的父母常年在外务工占35.3%(12/34),二者有统计学差异(X2=15.54)。结论免疫空白是麻疹暴发形成的重要因素,农村儿童的父母常年在外务工形成隔代抚养教育对计免工作有负面影响。  相似文献   
90.
Summary When the hand of the observer is used as a visual target, oculomotor performance evaluated in terms of tracking accuracy, delay and maximal ocular velocity is higher than when the subject tracks a visual target presented on a screen. The coordination control exerted by the motor system of the arm on the oculomotor system has two sources: the transfer of kinaesthetic information originating in the arm which increases the mutual coupling between the arm and the eyes and information from the arm movement efferent copy which synchronizes the motor activities of both subsystems (Gauthier et al. 1988; Gauthier and Mussa-Ivaldi 1988). We investigated the involvement of the cerebellum in coordination control during a visuo-oculo-manual tracking task. Experiments were conducted on baboons trained to track visual targets with the eyes and/or the hand. The role of the cerebellum was determined by comparing tracking performance defined in terms of delay, accuracy (position or velocity tracking errors) and maximal velocity, before and after lesioning the cerebellar dentate nucleus. Results showed that in the intact animal, ocular tracking was more saccadic when the monkey followed an external target than when it moved the target with its hand. After lesioning, eye-alone tracking of a visual target as well as eye-and-hand-tracking with the hand contralateral to the lesion was little if at all affected. Conversely, ocular tracking of the hand ipsilateral to the lesion side became more saccadic and the correlation between eye and hand movement decreased considerably while the delay between target and eyes increased. In normal animals, the delay between the eyes and the hand was close to zero, and maximal smooth pursuit velocity was around 100 degrees per second with close to unity gain; in eye-alone tracking the delay and maximal smooth pursuit velocity were 200 ms and 50 deg per second, respectively. After lesioning, delay and maximum velocity were respecttively around 210 ms and 40 deg per second, that is close to the values measured in eye-alone tracking. Thus, after dentate lesioning, the oculomotor system was unable to use information from the motor system of the arm to enhance its performance. We conclude that the cerebellum is involved in the coordination control between the oculomotor and manual motor systems in visuo-oculo-manual tracking tasks.  相似文献   
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