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941.
In the cat synapses between vesicle containing profiles were observed in ventral and dorsolateral pontine nuclei. The presynaptic elements consisted of two types of axon terminals: axon terminals characterized by a population of small (38-40 nm) round synaptic vesicles (SSV) and axon terminals containing pleomorphic synaptic vesicles (PSV). The postsynaptic pale elements (PP) had pleomorphic vesicles and some features attributed to dendrites. In the dorsolateral pontine nucleus most of PP profiles took part in serial synapses, usually as an intermediate component, they were rarely observed in triads. On the basis of their electron microscopical appearance and synaptic relations they might be considered to represent a dendritic part of putative interneurons.  相似文献   
942.
This paper reports on 1330 infants, from birth to 24 months old, suffering from diarrhoea and moderate to severe dehydration who were hospitalized in Tehran University Hospital over a period of 11 months. Fifteen per cent of them had signs of shock and 36% had marasmus. All patients were treated orally in two phases: rehydration therapy and maintenance therapy. For rehydration, an isotonic fluid (sodium 80 mmol l-1, potassium 20 mmol l-1) was administered at a rate of 40 ml kg-1 h-1 until all signs of dehydration disappeared. Following complete hydration, the patients were discharged and maintenance therapy was performed at home, by mothers, administering Maintenance Solution (sodium 40 mmol l-1, potassium 30 mmol l-1) ad libitum. Intravenous fluids were not used, even in severe dehydration. The efficacy and safety of this regimen were confirmed by rapid and successful rehydration in 99.7% of the patients and correction of a wide variety of electrolyte abnormalities present on admission, though some relapsed. The study suggests that this protocol could be employed in varied types and severities of dehydration and electrolyte abnormalities, and could also be used in both well nourished infants and in those with severe marasmus. It also demonstrates that mothers can serve as effective health workers and can perform successful maintenance therapy. Nine per cent of treated children required readmission to hospital within 24 h of discharge and a further 8% were hospitalized elsewhere with recurrent symptoms.  相似文献   
943.
944.
Skin Granulomas due to Mycobacterium gordonae   总被引:2,自引:0,他引:2  
A 38-year-old woman presented with small, ulcerated, red or bluish nodules on the right hand, clinically resembling mycobacterial granulomas; these appeared a few months after a bite by a rat, while the patient was collecting frogs in a pond in the Belgian Ardennes. The histopathologic picture was compatible with a diagnosis of mycobacterial infection and rare acid-fast bacilli could be found. Repeated bacteriologic investigations were performed and these led to the identification of a strain displaying characteristics of Mycobacterium gordonae. The skin condition responded well to rifampicin (300 mg/day) within 6 months.  相似文献   
945.
Forty-five displaced olecranon fractures including 14 accompanying dislocated radial heads and seven radial head fractures were treated over a 13-year period by the tension band wiring technique. The use of supplemental internal fixation when necessary allows excellent results with the use of this technique, even in the presence of severe comminution or radial head dislocation. Primary silicone radial head implants fractured in all three patients in which they were used, necessitating repeat surgery in two patients to date. While loss of motion in terminal extension was a common aftermath of displaced olecranon fracture (59%), it was usually minor and functionally insignificant. True Kirschner-wire migration was not a common problem and can probably be eliminated by proper technique. The presence of gaps in the intraarticular surface of the semilunar notch of the ulna produced no ill effects and was compatible with excellent results. If only those cases with isolated olecranon fractures in this series are considered, there were good and excellent results in 29 of 30 cases (97%). Excision of the olecranon fragment(s) should be reserved for those cases when anatomic restoration cannot be achieved with internal fixation.  相似文献   
946.
The aim of this study was to investigate the role of plasma glucagon levels on the blood glucose response to intravenous insulin administered continuously or in a pulsatile manner. Six type I diabetic patients proven to have no residual insulin secretion were investigated. Endogenous glucagon secretion was inhibited by a continuous intravenous infusion of somatostatin (100 micrograms/h) and replaced by exogenous infusions of the hormone at three different rates (7.5, 4.5, and 2.5 micrograms/h), resulting in three different plasma glucagon steady-state levels (i.e., approximately equal to 200, approximately equal to 130, and approximately equal to 75 pg/ml, respectively). Each subject, in random order and on different days, was infused intravenously with regular human insulin either continuously (0.17 mU X kg-1 X min-1) or with the same amount of insulin infused in a pulsatile manner (0.85 mU X kg-1 X min-1 during 2 min followed by 8 min during which no insulin was infused). At plasma glucagon levels approximately equal to 200 pg/ml, blood glucose rose from approximately 10 to approximately 13 mM without any difference between the two modalities of insulin infusion. For plasma glucagon levels approximately equal to 130 pg/ml, plasma glucose remained steady throughout the experiments, but during the last 40 min, plasma glucose levels were significantly lower when insulin was administered intermittently. This greater blood glucose-lowering effect of pulsatile insulin occurred earlier and was more pronounced for plasma glucagon levels averaging 75 pg/ml. We conclude that the greater hypoglycemic effect of insulin administered intravenously in a pulsatile manner in type I diabetics critically depends on plasma glucagon circulating levels.  相似文献   
947.
948.
Monandry (monogamy) in natural populations of anopheline mosquitoes   总被引:1,自引:0,他引:1  
Polymorphic Y chromosomes within two species of anopheline mosquitoes provide markers for testing if females are inseminated by one or more males in nature. Wild-caught females of Anopheles dirus (sp. A) and An. maculatus s.s. produced 291 and 55 families, respectively, which showed a single type of Y chromosome. One family of the former species showed two types of Y chromosomes. These field data support the idea, established from laboratory studies, that female mosquitoes are largely monandrous (monogamous). Such information is important in interpretation of population biological data and, practically, in attempts to control insect pests by use of genetically designed males.  相似文献   
949.
950.
High-frequency jet-ventilation (HFJV) was applied to 30 patients undergoing vertical partial surgery of the larynx for carcinoma of the vocal cords. This technique gave good surgical conditions as it interfered little with the air-ducts. It was carried out with a catheter of only 3 mm external diameter; control of ventilation during surgery was adequate, the average PaO2 being 27.9 +/- 5.6 kPa (209.3 +/- 4.2 mmHg) and the average PaCO2 5.4 +/- 1.4 kPa (40.5 +/- 10.5 mmHg). It avoided also the need for a tracheotomy. In the past, anaesthetic techniques were local anaesthesia combined with neuroleptanalgesia, endotracheal intubation or preoperative tracheotomy. None of these methods being satisfactory, our practice now includes first a nasotracheal intubation with an armoured tube at the beginning of the surgical procedure, followed by HFJV during the removal of the vocal cord, the tracheal tube being slightly pulled out. The tracheal tube is then put back in place before the thyroid cartilage is closed. The contra-indications are the same as those of HFJV. There are two types of complications: complications of HFJV itself, and postoperative complications due to the absence of tracheotomy. No accidents were observed. The only incidents seen were related to the lack of tracheotomy: subcutaneous oedema of the neck during the postoperative period in eight patients and moderate tracheobronchial congestion in five patients.  相似文献   
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