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951.
Two hydroxyl containing dithiocarbamates, sodium N-methyl-D-glucamine dithiocarbamate (NaG) and sodium dihydroxyethyl dithiocarbamate (NaY) have been examined as agents for the control of the renal dysfunction in rats given cisplatin. Of these, NaG was found to be the more effective in controlling such renal dysfunction when administered at 1 and 3 h after 5 mg cisplatin kg-1, i.p. Renal function was examined 5 days after the administration of cisplatin by measurement of serum and urinary levels of creatinine and urea, creatinine clearance, serum and urinary levels of Na+, K+, Mg2+, Ca2+, as well as the concentrations of these ions in the renal medulla and cortex. Treatment of rats given cisplatin with NaG at 1 and 3 h post cisplatin resulted in indices of renal function which were not significantly different from those of animals which had received no cisplatin. The sole difference was found to be a slight increase in renal cortical Na+ concentration.  相似文献   
952.
A multi-channel functional electrical stimulation (FES) system for the restoration of hand function of the quadriplegic is described. The system is composed of a personal computer NEC PC-880lmkII, peripheral electronic circuits and two kinds of sensors, i.e. an analog displacement sensor for volitional control (channel 1) and a logical sensor (high pitch sound or head switch, channel 2). Combination of the two channel signals allow three major function: 1) designation of the desired prehension pattern among cylindrical grasp, key grip and parallel extension grip; 2) selection of the operation status--'start', 'proportional control', 'hold', 'stop'--and, 3) volitional control which can be controlled by the shoulder movement. In the clinical application, Caldwell-Reswick type multistrand stainless steel percutaneous electrodes were used. In this FES system, standard multi-channel stimulation patterns were obtained from electromyographical analysis of joint movement of the upper extremities in normal subjects which gave us precise information about a role of each muscle during various kinds of motion. Such stimulation patterns have enabled us to restore motor function of the paralyzed upper extremities for activities of daily living (ADL).  相似文献   
953.
G I Hatton  Q Z Yang 《Neuroscience》1989,31(2):289-297
To establish the functional nature of the anatomically demonstrated main olfactory bulb inputs to the supraoptic nucleus, electrophysiological responses of intracellularly recorded supraoptic neurons to lateral olfactory tract stimulation were recorded in horizontal slices of basal forebrain and hypothalamus. A total of 71 synaptically influenced neurons were studied in slices from adult rats of both sexes. Of these, 60 cells (84%) were monosynaptically activated by olfactory tract stimulation; seven cells (10%) were activated via polysynaptic pathways; and four cells (6%) were characterized by long latency inhibitory responses. Lucifer Yellow was injected into 64 cells and subsequent immunocytochemical identification of 44 of these neurons showed that both oxytocin and vasopressin cells, in approximately equal numbers, were excited by olfactory stimulation. Polysynaptically mediated excitation, however, was only associated with oxytocin cells (six of the six identified cells). These results corroborate anatomical tract tracing data showing main olfactory bulb efferents to both supraotic neurons and to neurons of the perinuclear zone. Also supported are earlier speculations of olfactory participation in release of oxytocin and vasopressin during various physiological states.  相似文献   
954.
Y Takagishi  H Yamamura 《Brain research》1989,492(1-2):116-128
The course of cytological abnormalities and synaptogenesis of Purkinje cells were investigated in the culmen of cerebella from homozygous Gunn rats with hereditary hyperbilirubinemia from postnatal day 7 to adulthood (5-10 months old). The affected Purkinje cells were abundant at day 7. A large number of Purkinje cells reached the fully advanced stage of degeneration during the ensuring 16 days and disappeared between days 12 and 30. The Purkinje cells remaining at day 30 were less affected and recovered by the adult stage. Various abnormalities in Purkinje cell synaptogenesis with the parallel fibers, climbing fibers, and basket and stellate cell axons were observed. Primitive junctions between parallel fibers and Purkinje dendritic shafts were often found in adulthood. The parallel fiber boutons lacking postsynaptic partners and facing astrocytic processes were often noted from day 18 to adulthood. The persistence of such presynaptic elements suggests some mechanisms for stabilizing the synaptic elements once they have been formed. Many of the parallel fiber synaptic boutons with or without their postsynaptic partners were enlarged and were assumed to be transsynaptically affected by Purkinje cell damage. A number of climbing fiber synapses with perisomatic process of Purkinje cells, which are transient in normal synaptogenesis, were present at day 30 and a few of them were still found even in adulthood. Basket and stellate cell synapses were often found in abundance on the remaining Purkinje cells in adulthood, though they were not frequently encountered during the development period.  相似文献   
955.
A randomly selected sample of 662 12-year-old Hong Kong children, 529 of whom were Southern Chinese and 133 non-Chinese, was clinically examined for dental caries. The DMFT values were 2.76 and 1.66 for the Chinese and non-Chinese children, respectively. The D component for the Chinese children was 2.12, while for the non-Chinese children it was only 0.45. Approximately 24.0% of the Chinese children had attended the dentist because they were in pain. Only 3.8% of the Chinese children had sought orthodontic or preventive treatment, compared with 24.0% of the non-Chinese children. Although these findings indicate the caries experience to be well below the FDI/WHO global goal for the year 2000, there is a great need to increase the level of dental awareness among Chinese children.  相似文献   
956.
Two neonates who went into acute hypovolaemic shock due to a tight nuchal cord were successfully resuscitated. The occurrence of this life threatening complication in two low risk pregnancies emphasises the importance of having staff trained in resuscitation immediately available in the delivery unit.  相似文献   
957.
The aim of this study was to investigate the value of elemental diet in steroid-resistant and steroid-dependent Crohn's disease. Elemental diet (Vivonex HN, 39.4 +/- 9.2 kcal/kg/d) was delivered through a nasogastric tube at a constant rate. Twenty therapeutic periods lasting from 20 to 74 days (median, 32 days) were undertaken in 18 patients. Elemental diet was well tolerated. Mean values of hemoglobin, serum albumin, and serum transferrin increased significantly through the therapeutic period; body weight and anthropometric data did not change significantly. The short-term response to elemental diet was excellent in 11 cases, demonstrated by achievement of clinical remission and steroid withdrawal; six patients had an incomplete remission and remained slightly active or had to be maintained under low dose steroids; three patients did not respond to therapy and had to be operated upon. During the follow-up (6-30 months), 8 patients out of 17 had a relapse. Relapse was controlled by medical therapy in 5 cases and led to surgery in the 3 other cases. We conclude that elemental diet, as total parenteral nutrition, is an effective therapy of steroid-resistant and steroid-dependent Crohn's disease. However, elemental diet does not prevent relapse.  相似文献   
958.
959.
960.
To determine the clinical significance of regional left ventricular asynergy in patients with impending myocardial infarction, we recorded two-dimensional echocardiograms (2DE) serially and performed coronary angiography immediately after the hospital admission in nine patients with initial impending infarction and their last anginal attacks were within 48 hours. Left ventricular asynergy on the first 2DE was observed in six of nine patients during symptom-free periods (Group A: LV asynergy group). Five of the six patients had significant coronary artery lesions (greater than or equal to 75% stenosis) in at least one major coronary artery. Intracoronary filling defects were detected in four of the five patients. Another three patients without asynergy (Group B) had significant fixed stenosis. Coronary artery spasm was observed in two patients during coronary angiography, but no patient had intracoronary filling defects. Intracoronary nitroglycerin (0.1-0.3 mg) reduced the severity of coronary artery narrowing in two patients. In addition, urokinase (240,000-480,000 IU) via the corresponding vessel (PTCR) in the remaining seven patients resulted in reduction in the severity of coronary artery stenosis in four patients, but not in the remaining three patients. Left ventricular wall movement in the asynergy group improved rapidly and no asynergy was observed by the seventh hospital day in five of the six patients. Successful PTCR treatment resulted in improvement of left ventricular wall movement. No asynergy was found in the non-asynergy group throughout their hospitalizations. These findings indicated that abnormal left ventricular wall movement is found in patients with impending myocardial infarction, even during symptom-free periods, but the wall movement gradually improves. The 2DE observations are useful for estimating the clinical status and for planning precise therapy for impending myocardial infarction.  相似文献   
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