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991.
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
992.
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
993.
994.
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997.
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
998.
Is vasoactive intestinal polypeptide the principal transmitter involved in human penile erection? 总被引:5,自引:0,他引:5
Previous work from this laboratory reported on the effects of several autacoids and other agents on strips of human corpus cavernosum (cc) muscle. These investigations indicated the presence in the cc muscle of a) atropine-sensitive cholinoceptors, b) alpha- and beta-adrenoceptors and c) a non-adrenergic non-cholinergic mechanism. Several recent publications have presented evidence in support of the possibility that vasoactive intestinal polypeptide (VIP) is an important, or the chief, transmitter in human penile erection. This paper describes the actions of VIP and other compounds on the cc muscle and the effect of intracavernous injection of VIP in volunteers. Among the agents tested, VIP was the most potent relaxant of the cc muscle. This effect, which was seen at a dose as low as 0.03 nM, was suppressed by VIP antiserum. The response of the isolated penile vasculature to VIP was similar. VIP antiserum had no effect on the relaxation of the cc muscle produced by field stimulation. In five of the seven subjects given intracavernous VIP (1.0 micrograms.) some degree of penile enlargement was evident, but none had an erection. It is suggested that local release of VIP, withdrawal of the alpha-adrenoceptor mediated tonic supply to the penis and the activation of the latter's beta-adrenoceptors are all probably involved in penile erection in man. 相似文献
999.
K Murata H Itoh G Todo T Itoh M Kanaoka M Furuta K Torizuka 《Investigative radiology》1986,21(1):24-30
This study was undertaken to clarify the microvascular anatomy of the normal human bronchial circulation, focusing on the bronchial venous system and its communication with the pulmonary circulation. Ten normal lungs obtained at autopsy were studied. Bronchial arteriography was performed in six lungs, pulmonary arteriography in two lungs, and pulmonary venography in another two. Using radiologic methods, including microradiography, and serial histologic sections, we found numerous bronchial venous plexuses around the airways and blood vessels into which the bronchial capillaries drained. Frequent communications of the venous plexuses with the pulmonary veins and neighboring alveolar capillaries were also demonstrated. The bronchial venous plexus and its close connection with the pulmonary circulation may be important in various pathologic conditions involving the interstitial space, such as interstitial pulmonary edema. 相似文献
1000.