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981.
The effects of repeated hyperbaric exposures on inner ear function and morphology in guinea pigs were investigated with auditory electrophysiological testing, histopathological and electron microscopic techniques associated with enzyme histochemical method. The results showed that repeated hyperbaric exposures, though considered "safe," did cause damage to the cochlear system. Possible causes of the pathology include direct effects of repeated compression and decompression on the ear, and the possibility of inner ear decompression sickness and barotrauma cannot be excluded. 相似文献
982.
Phytate was digested by wheat bran phytase to yield inositol tetrakisphosphate. Periodate-oxidized inositol tetrakisphosphate (oxyIP4) was coupled by means of reductive alkylation to hemoglobin and the covalent dextran-hemoglobin conjugate to yield the rightshifted (rs) compounds rsHb and rsDxHb, respectively. The variations of the oxygen dissociation curves of these molecules with pH and temperature were compared to those of hemoglobin. The variations with pH were found to be less pronounced for these rightshifted forms. An extensive decrease in the half-saturation oxygen tension was observed, however, with both rsHb and rsDxHb, as in the case of unmodified Hb. Modification of hemoglobin by oxyIP4 at the polyphosphate site was suggested by the lack of a further rightshifting effect of phytate on rsHb, and by the similarity between the difference spectrum of rs-methemoglobin and the difference spectrum induced by the addition of phytate. 相似文献
983.
Microcirculation and blood perfusion in unphysiological flaps were observed with rabbit ear microcirculation chamber. The microcirculation of the venous flap in two days after operation was reestablished mainly by diversion of blood flow through the "to and fro" movement of venous blood. Arteriovenous anastomoses were gradually opened, resulting in the microcirculation to restore normal perfusion, venous blood through the anastomoses into arteriole then to capillaries. The microcirculation of arterialized venous flaps was almost the same as that of the venous flaps. In two days after operation, the diversion of blood flow perfused the capillaries under high pressure, so that the flow velocity and rate were much faster and larger than those of the venous flaps. The microcirculation of venouslized arterial flap, nourished by venous blood through the arterial system, was the same as that of the physiological flap. But the capillaries were perfused venous blood flow, and the blood flow velocity and rate were much slower and smaller than those of the physiological flap. 相似文献
984.
985.
For the purpose of evaluating the therapeutic effect of antihistamines, we have set up an assay method called the "Skin Test Inhibition Index" (STII). Twenty subjects with hay fever were given astemizole (10 mg/d) for 7 days. Skin titration tests were carried out before and after treatment. Significant inhibition of the skin test reaction by astemizole was demonstrated (STII = 91). Another group of 6 hay fever patients was given astemizole (10 mg/d) for 10 days, and STII was determined on days 5 and 10 and on days 7, 14 and 21 after treatment. STII were calculated as 12, 108, 90, 10 and 7, respectively. These results demonstrate that astemizole is a long-acting antihistamine. 相似文献
986.
Cystine stones: the impact of new treatment 总被引:1,自引:0,他引:1
X Martin M Salas M Labeeuw N Pozet A Gelet J M Dubernard 《British journal of urology》1991,68(3):234-239
The hardness and frequent recurrence of cystine stones present a special challenge to the urologist. In this study, 15 cystinuric patients (11 males, 4 females; mean age 36 years, range 17-54) were treated and followed up over a period of 30 months (range 2-40). Most patients had previous history of open surgery. The diagnosis of cystinuria was confirmed by metabolic studies and infrared spectrometry of stones. Over the follow-up period recurrence was observed in 23 instances in 11 patients, leading to 38 "stone treatments" on 74 cystine stones. The percutaneous approach was used alone in 9 cases and in association with extracorporeal shock wave lithotripsy (ESWL) in 9 cases. ESWL was used alone in 18 cases. Medical treatment included high fluid intake, alkalinisation and Thiola (tiopronin, N-(2-mercaptopropionyl)glycine) in 6 patients. The overall stone-free rate assessed 3 months after treatment was 44.7%, which compares poorly with the rate for non-cystine stones. The recurrence rate is very high and instrumental treatment should not therefore be used excessively; it is indicated only for stones that are symptomatic or refractory to intensive medical therapy. 相似文献
987.
X Gao 《中华神经精神科杂志》1991,24(6):362-4, 384
Three cases of "Top of the basilar" syndrome are reported. The clinical manifestations included the consciousness disturbance, pupillary and oculomotor abnormalities. One of the 3 cases got cortical blindness. It is emphasized that the possibility of the TOB syndrome should be considered when unconsciousness arose suddenly, accompanied by lid, pupil and oculomotor disturbances without the motor and sensory disturbances. Usually, a bilateral symmetric butterfly hypodensity could be found in the thalamus on CT scan. In addition. It was valuable findings that the infarct lesions have been shown in the mesencephalon, pons, cerebellum, occipital and medial temporal lobe on CT scans. 相似文献
988.
Awareness of illness in schizophrenia 总被引:6,自引:0,他引:6
This article reviews the literature on "poor insight" or unawareness of illness in schizophrenia. A large body of knowledge representing several different perspectives on insight has developed. This work can be divided into three broad categories, suggesting an important role for insight in the phenomenology, pathophysiology, and treatment of schizophrenia. The argument is made here that many of the self-awareness deficits observed in schizophrenia are of diagnostic significance, are neurally based, and are indispensable in guiding treatment decisions. In addition, this article proposes guidelines for assessing unawareness of illness in schizophrenia and discusses the relevance of such deficits to the diagnosis of schizophrenia. 相似文献
989.
Campylobacter jejuni is a major cause of human enteritis which mimics the inflammatory bowel disease (IBD). In this study, microstructural changes on the surfaces of the murine gastrointestinal tract persistently colonized by Campylobacter jejuni, strain GJ-S131, were investigated by using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results revealed that the appearance of the gastrointestinal mucosa in both BALB/C and KM mice resembled that in human with inflammatory bowel disease. Under SEM, the mucosa of the jejunum and ileum, with broken or distorted villi had a "worm eaten" look; crypts were irregular in shape and size, and the mucosa showed atrophy, especially in the colon. Epithelial junctions demonstrated furrows, clefts or deep crevasses, with exudates containing a large number of leukocytes. Cytologic appearances were characterized by microvilli dysplasia and/or atrophy, patchy erosions or necrosis and pelade-like appearance due to absence of microvilli, which were similar to the findings under TEM.
相似文献
990.
According to our supposition that "humoral mechanism" plays an important role in the pathogenesis of portal hypertension due to cirrhosis, antagonists to some of humoral substances would lower the portal pressure in cirrhotic patients. Wedged hepatic venous pressure (WHVP) was used as an indicator for changes of portal pressure. Cimetidine was given intravenously to 8 cirrhotic patients, in whom an average lowering of 0.72 kPa (7.3 cm H2O) of WHVP was observed subsequently. This change was of clinical significance as compared with the previous results of splenorenal shunting operations.
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