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921.
Fourty-four narcotized rats were split into two equal groups, one being treated with nimodipine and the other with a placebo. By use of norfenefrine the blood pressure was raised to values of 150 and 180 mm Hg within the limits of the autoregulation of brain perfusion and under continuous measurement. Fifteen minutes after application of the standard tracer, horseradish peroxidase, the animals were exsanguinated using a saline perfusion and then perfusion-fixed with Karnovsky's solution. After development of the peroxidase staining the brain sections were evaluated and then allocated to their respective groups. In brain tissues from the experimental group significantly more frequent perivascular accumulations of horseradish peroxidase reaction product were found (P less than 0.001). In electron micrographs it could be seen that the tight junctions were intact and that there was a neuroendothelial transport, with horseradish peroxidase-filled vesicles, in the endothelium, muscle cells, and brain parenchyma. These vesicles represent a medium of transport for all proteins of high molecular weight and can therefore result in brain edema. It is concluded that nimodipine damages the blood-brain barrier by disturbance of the autoregulation of the cerebral blood flow. 相似文献
922.
E J Swift 《General dentistry》1986,34(6):468-471
923.
A Hugoson G Koch T Bergendal A L Hallonsten L Laurell D Lundgren J E Nyman 《Swedish dental journal》1986,10(3):103-117
The aim of the present study was to present data from dental care habits and knowledge of oral health in two cross-sectional studies carried out in 1973 and 1983. A random sample of approximately 1000 individuals evenly distributed in the age groups 3, 5, 10, 15, 20, 30, 40, 50, 60 and 70 years was studied for each of these two years. In the 1983-year examination 80 individuals 80 years of age were also included. All subjects were inhabitants of the community of J?nk?ping, Sweden. A questionnaire about dental care habits and knowledge was used in combination with a clinical and radiographical examination. The participants answered 23-101 questions. The same questions were raised in 1973 and 1983. For most age groups more then 80 per cent visited a dentist yearly in 1983. This yearly attendance was higher than that for 1973. In the 20-year-old group 14 per cent of the individuals received dental care in the PDS in 1973 compared to 63 per cent in 1983. The main reason to visit a dentist in 1973 was by the patient's own initiative while in 1983 the appointments were based on the dentist's initiative. The number of subjects that felt discomfort in connection with a visit to the dentist had decreased between 1973 and 1983. Knowledge about the etiology of caries had increased between 1973 and 1983 was not the case for gingivitis and periodontitis. An increase had occurred in toothbrushing frequency and the use of toothpicks and disclosing tablets but this between 1973 and 1983. In 1983, 98 to 93 per cent of the subjects in the age groups 10-30 years had been exposed to topical fluorides. The corresponding figure for 30-year-olds in 1973 was 1 per cent. It is obvious that during the period 1973 to 1983 there has been an increase in dental attendance, knowledge of dental diseases, oral health and the use of preventive measures. 相似文献
924.
A method for detecting the growth of micro-organisms in blood culture by a visual signal is described. The system utilises a single blood culture medium that has been specifically formulated to support growth of aerobic, anaerobic, and microaerophilic micro-organisms. The system is based on the principle that when micro-organisms grow in the medium in a sealed bottle their metabolic products create positive pressure. This positive pressure displaces the infected blood and broth into an upper chamber, which acts as a visual signal of microbial activity. All the test micro-organisms, when inoculated at less than 20 colony forming units into simulated human blood cultures, gave a positive signal. 相似文献
925.
926.
T C Cook R E Laporte R A Washburn N D Traven C W Slemenda K F Metz 《Medicine and science in sports and exercise》1986,18(6):653-657
Physical activity has been associated with reduced risk of coronary heart disease. A mechanism for the reduced risk may be through increased high density lipoprotein cholesterol (HDL-C) and subfractions, in particular HDL2-C. Research associated with increased physical activity investigating HLD-C have assessed the effects of intense aerobic activity. The current research evaluated the relationship between low intensity, long duration activity to HDL-C and subfractions in 35 active postal carriers. Measurements of physical activity via the Large Scale Integrated monitor and reported miles walked, and lipoproteins were assessed at 3-month intervals over a 1-year period. Reported miles walked/day (5.3) was significantly correlated with HLD2-C (r = 0.50, P = 0.003) and approached significance for HDL-C (r = 0.29, P = 0.06). The Large Scale Integrated measures were correlated with HDL-C (r = 0.44, P = 0.008) and HDL2-C (r = 0.44, P = 0.007). Controlling for either age, alcohol consumption, body mass index, or leisure time activity did not reduce the relationship between reported miles walked or Large Scale Integrated readings and HDL2-C, suggesting that the increased HDL-C was the result of long duration, low intensity physical activity. 相似文献
927.
Nonconvulsive status epilepticus may be subdivided into generalized (absence) status and complex partial status. The latter is regarded as a rarity, whereas the former constitutes the dominant part of the hitherto reported cases. We report 10 consecutive cases of adult patients with nonconvulsive status epilepticus, all documented by ictal electroencephalographic (EEG) recordings. Five had a complex partial status; the origin of the complex partial status appeared to be frontal in four of these patients. Three had recurrent complex partial seizures with incomplete recovery between seizures, and two had more continuous symptoms. One of the latter exhibited neither motor phenomena nor automatisms. The effect of diazepam or clonazepam was immediate in all 10 cases though transient in eight. A lasting control of the status was not achieved in six patients until i.v. phenytoin was added. The difficulties in the differentiation between complex partial status and absence status despite ictal EEG recordings are discussed, illustrated by a case with seizure discharges of a focal onset which rapidly generalized. The study indicates that complex partial status may be more common and the clinical expressions of absence status more variable than hitherto recognized. 相似文献
928.
To study the effect of sorbinil on the alteration of the blood-retinal barrier, 32 adult-onset, non-insulin-dependent diabetic patients with minimal or no retinopathy were randomly assigned to receive either oral sorbinil (250 mg once a day) or a placebo for 6 mo. All patients underwent fundus photography, fluorescein angiography, and vitreous fluorophotometry before treatment and at 3 and 6 mo after treatment. Vitreous fluorophotometry data showed that the alteration of the blood-retinal barrier increased significantly less in the sorbinil-treated group compared with the placebo group during the 6-mo study period. Side effects were limited to hypersensitivity reactions, with skin rash and fever, in only 2 of the 16 patients who received the drug. These hypersensitivity reactions disappeared with discontinuation of the medication. Aldose-reductase inhibition may play an important role in stabilization of the blood-retinal barrier in early diabetic retinopathy. 相似文献
929.
930.
Henrik J. O. Bengtsson M.D. Albert E. A. Broomé M.D. Ph.D. Ulf Rimér M.D. 《World journal of surgery》1986,10(3):510-514
The use of a vascularized jejunal patch for the reconstruction of bile duct injuries is presented. The method has been used in 1 patient with a common bile duct stricture and in 1 patient with a noncircumferential bile duct defect. The procedure has the advantages of technical simplicity, primary mucosal coverage, lasting elasticity, and minimal risk for stricture formation.
Resumen Se presenta el uso de un parche vascularizado de yeyuno para la reconstrucción de lesiones del canal colédoco. Se reseca un segmento móvil del yeyuno lo suficientemente amplio para cubrir el defecto, asegurándose de que existe buena irrigación para el segmento, visualizando los vasos por transiluminación con luz ordinaria. La continuidad del intestino es restablecida mediante anastomosis término-terminal. Se utiliza la parte mesentérica del segmento intestinal, el cual es ascendido por vía retrocólica. Se sutura mucosa con mucosa con una sola capa de puntos separados de ácido poliglicólico 5-0. Se coloca un tubo-en-T para drenaje, el cual es retirado a las 6 semanas. El método ha sido utilizado en un caso de estenosis del colédoco y en un caso con un defecto circunferencial del mismo canal biliar. El procedimiento tiene la ventaja de la simplicidad técnica, la cobertura primaria de la mucosa, la elasticidad permanente y un mínimo riesgo de que se produzca estenosis.
Résumé L'emploi d'un patch jéjunal bien vascularisé pour traiter les blessures de la voie biliaire fait l'objet de l'article. La méthode a été utilisée pour un cas de sténose de la voie biliaire principale et un cas de plaie n'intéressant pas la totalité de la circonférence du canal biliaire. Elle a pour avantages sa simplicité technique et le fait qu'elle assure une couverture muqueuse, sa persistante élasticité et le fait qu'elle présente un risque réduit de sténose.相似文献