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991.
992.
Two monoclonal antibodies, bd-17 and bd-24, specific for the beta- and alpha-subunit of the GABAA/benzodiazepine receptor/chloride channel complex, respectively, were used to determine the subcellular distribution of immunoreactivity in the cerebellum by electron microscopy. The 2 antibodies showed similar antigen distribution on the plasma membrane (except in the rat; bd-24 does not recognize the rat antigen), but intracellular immunoreactivity was more prevalent for the alpha-subunit. The plasma membrane of all neuronal types was immunopositive. The degree of immunoreactivity varied greatly between different types of cell, but it was stereotyped among individual cells of the same type. Granule cells showed the strongest immunoreactivity, not only on their dendrites which receive synapses from GABA-containing Golgi cell terminals, but also on their somata which do not receive synapses. Stellate and basket cells were somewhat weaker in immunoreactivity. Purkinje cells were only weakly positive on their somatic membrane but stronger on their dendritic shafts and spines. Golgi cells showed negligible if any immunoreactivity. Neurons of the deep cerebellar nuclei were strongly immunopositive along their plasma membrane. Immunoreactivity was strong in cisternae of the endoplasmic reticulum and in the Golgi saccules of stellate and basket cells, variable in Purkinje cells, while granule cells were rarely immunoreactive intracellularly. It is suggested that these differences reflect differences in the turnover of the receptor complex in the different cell types. The synaptic clefts established by boutons of the GABAergic stellate, basket, and Golgi cells were immunopositive, as were many synapses in the deep cerebellar nuclei. However, immunoreactivity was also present along the nonjunctional plasma membrane, and it was concluded that this reflected the distribution of the antigen. The synaptic clefts at the presumed glutamate-releasing parallel and mossy fiber terminals were almost always immunonegative. No immunoreactivity was detected on axons, nerve terminals, or glial cells. The results demonstrate that different neuronal types express the GABAA/benzodiazepine receptor/chloride channel complex to different degrees. The distribution of the receptor complex suggests that the cellular topography of GABAergic influence is not governed by the precise spatial arrangement of the receptors but by the precise placement of the GABA-releasing terminals, a characteristic of the cerebellar circuit.  相似文献   
993.
With a view to modifying the respective behaviors of patient, protector and operator so that a relationship of reliability can be established among them, we have adopted the training for dental treatment in the medical care system for handicapped children. We took this opportunity to classify the present handling methods at the practice of medical care into 4 groups (A, B-1, B-2, C) and to examine the training effect in each group and its features. [Method] On 145 patients having received treatment in the Dental Center for the Handicapped Children in our Hospital, number of patients by group, average age at the first examination, average training frequencies before and after treatment, average treating frequency, behavior in the training and relationship between each group and the disorder were examined for the card. [Results] 1) About 40% of the subjects for examination became capable of receiving treatment without any controlling appliance before the final treatment. 2) Average training frequency and average treating frequency had higher values of B-1 group than for other groups. 3) Behavioral estimation during the training revealed that A and B-1 groups showed better performance in mouth washing, brushing and cleaning by brushing than B-2 group, but the case was the contrary with oral use of three-way syringe and the vacuum. [Conclusion] Application of various behavior-modifying techniques to the training for dental treatment in children with psychosomatic disorder made its effect and features.  相似文献   
994.
No method has been reported for measuring CBF, repeatedly and noninvasively, in the rat brain. A new method is described, which is noninvasive to the brain, skull, or cervical large vessels. Two pairs of coincidence detectors were positioned, one over the rat brain and the other at the loop of a catheter inserted into the femoral artery. The coincidence head curve and arterial curve were recorded after intravenous injection of 1-[11C]butanol in 15 rats. CBF was calculated by one-compartment curve fitting ( CBFo ) from 1-min data and with the recirculation corrected height/area method from 3-min data ( CBFh X 3 min) and 5-min data ( CBFh X 5 min). CBFo agreed well with CBFh X 5 min, although a slight overestimation was observed in CBFh X 3 min. The normal CBFo in the normocapnic group (n = 6, paCO2 36.7 +/- 2.3 mm Hg) was 1.76 +/- 0.49 ml/g min (mean +/- SD). A good correlation was observed between CBFo (y) and PaCO2 (x), and the regression line was y = 0. 0629x -0.715 (r = 0.88, p less than 0.0001). We concluded that this method gives the stable blood flow values noninvasively and with a minimum loss of blood (less than 0.28 ml per measurement). Applications of this method include activation studies, studies on the effect of drugs and treatments, and water and oxygen extraction fraction studies using different tracers in the same rat.  相似文献   
995.
996.
Experiments using 3 analgesic tests, the tail-pinch, hot-plate and tail-flick methods, were done to evaluate the roles of the spinal noradrenergic and serotonergic systems in the production of morphine analgesia in rats. To deplete noradrenaline or serotonin in the spinal cord, 6-hydroxydopamine or 5,6-dihydroxytryptamine was given intrathecally. 6-Hydroxydopamine suppressed the antinociceptive effects of morphine injected systemically or intracerebrally (into the nuclei reticularis gigantocellularis and paragigantocellularis or into the periaqueductal gray matter) in the tail-pinch test, but not significantly in the hot-plate and tail-flick tests. Conversely, 5,6-dihydroxytryptamine suppressed the antinociceptive effects of systemically given morphine in the hot-plate test, but not significantly in the tail-pinch and the tail-flick tests. The results not only provide further evidence for the involvement of the descending inhibitory systems in morphine antinociception, but also show that the extent of participation of the spinal noradrenergic and serotonergic systems in the effects of morphine has to be carefully assessed as different analgesic tests (tail-pinch, tail-flick and hot-plate) yield different results.  相似文献   
997.
A 16-year-old, 28-week pregnant woman was admitted to our hospital with multiple bone fractures caused by a traffic accident. She had massive blood transfusion because of anemia in her laboratory findings and ritodrine hydrochloride was administered because of the fear of threatened abortion. She developed a cough with bloody sputum on the 4th day after admission, and developed pulmonary insufficiency with PaO2 41.0 torr and presented bilateral diffuse infiltrates on chest roentgenograms on the next day. Swan-Ganz catheterization revealed normal pulmonary capillary wedge pressure and analysis of the lavage fluid from the patient showed an increase in the percentage of neutrophils (40.0%) and the existence of leukotriene B4 which is known to be the most potent chemokinetic and chemotactic agent for neutrophils. Her condition was considered to be permeability edema developing adult respiratory distress syndrome (ARDS) and 1 g/day of methylprednisolone was administered intravenously for 3 days, which brought about remarkable improvement of her respiratory failure. This report suggests that analysis of the lavage fluid may provide useful information for the early diagnosis of ARDS and the indications of corticosteroid treatment.  相似文献   
998.
999.
Three cases of bilateral traumatic abducens nerve palsy were presented and the mechanism of damage to the abducens nerve was discussed in relation to the analysis of traumatic force at the time of impact and topographical anatomy of the abducens nerve in detail. Case 1. A 70 year old man sustained a traffic accident with one hour loss of consciousness. Physical examination revealed a contused area on the medial side of his right forehead. Neurological examination revealed bilateral abducens nerve palsy (Fig. 1). There were no ther cranial nerve abnormalities. Roentgenograms of the skull, including views of the base and orbit showed no fracture. At follow up examination 12 months later, bilateral Duane's retraction syndrome could be noticed with slight increase in size of the pupil on each side of lateral gaze (Fig. 2). Case 2. A 32 year old women sustained a traffic accident with 31 days of loss of consciousness. At the time of admission, bilateral abducens nerve palsy and slight left hemiparesis were noticed in semicomatose condition. Right carotid angiogtam showed no evidence of intracranial hematoma. One month later, the right eye began to abduct and 2 months later, the left eye began to abduct. Three months after the injury, bilateral abducens nerve palsy could no longer be demonstrated. No retraction syndrome was observed during this period. Case 3. A 3 year old boy sustained a traffic accident with 32 days of loss of consciousness. At the time of admission, neurological examination showed bilateral abducens palsy and left sided decerebrate posture in comatose condition. At the time of discharge 3 months after admission, bilateral abducens palsy, right hemiataxia, left spastic hemiparesis and scanning speach were noticed. Three months later, right eye began to abduct and 4 months later, the left eye began to abduct. At follow up examination 6 months later, there was no evidence of abducens nerve palsy. Topographical details of anatomy of the abducens nerve are shown in Fig. 3, 4. It is greatly speculated that both abducens nerves are streched by the lineal accerelated force on mid sagittal plane at the time of impact, then the apex of petrous pyramid acts as the fulculum, so that the abducens nerves are compressed, contused and streched at this point (Fig. 5-a). The authors pointed out that the abducens nerve are impossible to be damaged at the petroclinoid ligament (Grüber's lig.) by the upward movement of the brainstem, because the abducens nerve is fixed downward below this ligament by the dura and apex of the petrous pyramid (Fig. 4-b, c). One case showed bilateral acquired retraction syndrome with slight increase in size of the pupil on each side of lateral gaze, the fact greatly suggesting that the sympathetic nerve have intimate relationship to the miss direction during the recovery stage of abducens nerve palsy.  相似文献   
1000.
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