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991.
The authors investigated the effect on the brain of red blood cells that had been modified by contrast media. Rat blood was mixed with an equivolume of contrast media, and up to 200 microL of the mixture was infused to the internal carotid artery of the rat. Evans blue was administered intravenously to assess the integrity of the blood-brain barrier (BBB). Immediately after the death of the animal, or 2.5 hours after the infusion, the brain was removed for evaluation of the degree of BBB destruction and edema. Extensive destruction of the BBB, cerebral edema, and death of the animals were induced by infusion of blood mixed with an ionic contrast medium, such as diatrizoate and iothalamate, which deformed red blood cells. Microscopic observation showed atrophy and necrosis of nerve cells and decomposition of nerve fibers in the affected area of the brain. Cerebral damage was not observed in rats injected with blood mixed with a nonionic contrast medium such as iopamidol, iopromide, or metrizamide, which had less effect on red blood cells. Cerebral damage also was observed in the rats injected with blood mixed with a hyperosmotic solution of mannitol, as well as washed red blood cells mixed with an ionic contrast medium. This study's results indicate that hyperosmotic ionic contrast media affect red blood cells and cause disturbance in cerebral circulation. 相似文献
992.
Isolated ultrafiltration, hemodialysis & peritoneal dialysis (Tx) were recently used in the treatment of intractable heart failure (HF). We examined the relation between the response of HF to Tx and the residual kidney functions. Tx was carried out in 17 patients (Pts) with HF who did not respond to aggressive medical treatment. Ten Pts (R) responded to Tx and 7 Pts (N) did not. Serum urea nitrogen (UN), creatinine (Cr), uric acid (UA), sodium (Na), potassium (K), and chloride (Cl) concentrations on admission and before Tx were not different between R and N. Urine UN, Cr, Na, K, and Cl on admission and before Tx were also not significantly different. Fractional sodium excretions (FENa), renal failure indices (RFI), and urine/plasma Cr ratios (U/P Cr) on admission were 2.0 +/- 1.6, 2.7 +/- 2.2, and 30.5 +/- 20.0 in R and 5.9 +/- 4.2, 8.2 +/- 6.0 and 11.5 +/- 3.8 in N. They were significantly different (p less than 0.05). However, these did not differ before and after Tx. These data show that FENa, RFI and U/P Cr might be useful indices in predicting the responsiveness of intractable HF to Tx. 相似文献
993.
994.
N D Hawass M G el-Badawi J A Fatani A A Meshari F S Abbas Y B Edrees F A Jabbar M Banna 《AJNR. American journal of neuroradiology》1987,8(4):691-695
To assess the length of the spinal cord relative to the vertebral column during fetal development, we performed translumbar myelograms on 340 spontaneously aborted fetuses. Of these, 146 were selected for study. There were 76 males and 70 females, with fetal age ranging from 7 to 33 weeks. Significant variation in the level of spinal cord termination was found in fetuses between 12 and 25 weeks gestational age. In fetuses between 25 and 33 weeks gestational age, the cord ended at or above the third lumbar vertebra. 相似文献
995.
G F Sasso M Ceccanti E Nardi G Valicenti M A Savina N Stella F Zacco 《Panminerva medica》1989,31(1):30-33
The activity of LCAT (the controlling enzyme for cholesterol esterification in plasma) is known to be reduced in alcoholic cirrhosis, while little is known about early stage (liver steatosis) alcoholics. In this study, LCAT activity was assayed by Stokke and Norum's method, before and after a 15-day sobriety period, in liver steatosis and in cirrhosis alcoholics. Before alcohol withdrawal, LCAT activity was depressed in both groups. After the sobriety period, LCAT activity was significantly raised in liver steatosis patients, but was still lower than in controls; in cirrhosis patients, it was increased, but not significantly. According to our results, LCAT activity impairment in alcoholic liver disease is sustained by both the hypothesized mechanisms, alcohol-related metabolic disorders and lowered LCAT-enzyme production, but to different degrees, depending on the stage of the disease. In liver steatosis, metabolic disorders play a major role, as a liver-impairment-induced decrease in LCAT production seems rather unlikely, and increased LCAT activity is more likely to be sustained by metabolic normalisation than by any recovery of the damaged liver. However, the lack of improvement in about 20% of patients, and the fairly wide scattering of individual data, suggest a minor LCAT production impairment in liver steatosis too. In cirrhosis, the major role seems to be played by a permanent decrease in LCAT production, as no significant rise in LCAT activity was observed after alcohol withdrawal. However the restored LCAT activity observed in some patients could be related to improvement in the metabolic disorder, thus confirming the effectiveness of this mechnism in cirrhosis too.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
996.
Evidence for a defect in urinary concentrating ability in primary aldosteronism and its reversal by adrenal surgery 总被引:1,自引:0,他引:1
Of 15 patients with primary aldosteronism, 7 had idiopathic adrenal hyperplasia (IHA) and 8 had aldosterone-producing adenoma (APA). In order to determine any renal problems involved in the treatment, the renal clearance of these patients was analyzed and the results compared with those obtained from 12 patients with essential hypertension. With water diuresis or under antidiuresis status, levels of urine volume, Cosm and CH2O in patients with APA were greater (p less than 0.05-p less than 0.001) than those of patients with essential hypertension, while the fractional tubular sodium delivery of the former patients was lower than that of the latter patients (p less than 0.001 or less than 0.05). A similar tendency was observed in clearance studies in patients with IHA, although to a lesser extent. Adrenal surgery for patients with APA normalized these values, but administration of trilostane (3 beta-hydrosteroid dehydrogenase inhibitor) to patients with IHA failed to improve these values. These results indicate that impaired urinary concentrating ability as well as reduced urinary diluting capability is a common feature of primary aldosteronism. Such impaired renal function was improved only in patients with APA after adrenal surgery. 相似文献
997.
T López-Alburquerque A García Miguel J J Ruiz Ezquerro J de Portugal Alvarez 《Journal of neurology, neurosurgery, and psychiatry》1987,50(4):428-434
The nerve action potential at the elbow and somatosensory evoked potentials (SEPs) at the scalp were recorded over 30 minutes of tourniquet-induced limb ischaemia in 10 diabetic patients and 10 controls. According to the SEP changes, an increased resistance to nerve ischaemia in diabetic patients was observed. The pathways involved in SEP conduction are discussed. 相似文献
998.
999.
C G Watson T Kucala G Angulski P Vassar 《The Journal of nervous and mental disease》1987,175(1):34-40
This project was designed to test two hypotheses drawn from a new formulation explaining the exaggerated winter birthrate among hospitalized schizophrenics. The first is that the supposed exaggerated winter birthrate among process schizophrenics actually represents a reduction in spring-fall births caused by prenatal exposure to infectious diseases during the preceding winter--i.e., a high prenatal death rate in process preschizophrenic fetuses. The second is that the level of negative symptoms in survivors at risk for schizophrenia who were born after winters with high infectious disease rates is exaggerated. The findings provided some tentative support for this formulation. Compared with counterparts born after low-disease winters, schizophrenics born after winters with high disease incidences tended to show lower (more reactive) scores on a measure of the process-reaction dimension but higher anhedonia scores. 相似文献
1000.
T Iino N Toyosaki T Katsuki T Noda T Natsume T Yaginuma S Hosoda M Furuse 《Clinical nuclear medicine》1987,12(9):688-693
The perfusion territories in polar representations of stress Tl-201 rotational myocardial imaging in patients with angina pectoris who had one diseased coronary segment were analyzed. The lesions proximal or distal to the first major septal perforator in left anterior descending arteries were detected by the presence or absence of defects at the base of the anterior septum. Right coronary artery lesions were detected by the presence of defects at the basal posterior septum, in contrast to the preservation of myocardial uptake at this portion in lesions of the left circumflex artery. The specific defect patterns were detected in cases with lesions at the first diagonal, obtuse marginal, and posterolateral branches. Recognition of these defects in the polar maps allows detailed detection of diseased coronary arterial branches. 相似文献