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排序方式: 共有10000条查询结果,搜索用时 17 毫秒
991.
Follow-up examinations of 52 anginal patients who have received combined treatment involving plasma sorption indicate a good response in 77%, satisfactory in 11.5% and no response in 11.5% of the examinees. Exercise tolerance and performance increased by 34.3 and 52.1%, respectively. The scope of chemotherapy was related to the initial severity of the disease. Clinical remission after plasma sorption lasted 8.4 +/- 0.7 months. 相似文献
992.
993.
994.
C A Mestres M Acosta C Paré R Carta?á A Martínez J L Pomar 《Revista espa?ola de cardiología》1991,44(6):408-410
Minor experience still exists in our country with regard to the use of valve homografts in cardiac surgery. Only a few implantations have been performed in cases of right ventricular outflow tract reconstruction in addition to our own experience in cases of infective endocarditis of the aortic valve. We present a case of aortic valve replacement by using an antibiotic-sterilized fresh pulmonary valve autograft. The case is described and the possible advantages of the use of pulmonary allografts in the aortic position are discussed. 相似文献
995.
A stimulation of the Na(+)-H+ exchanger has been shown in platelets of hypertensive man and lymphocytes of spontaneously hypertensive rats. In the present paper, human mononuclear leukocytes (HML) were investigated in 12 patients with essential hypertension with regard to the activity of the Na(+)-H+ exchanger and HML volume. The swelling of HML in isotonic sodium propionate was determined using a Coulter Channelyzer. Compared with matched normotensives, the cell volume of HML in a physiological buffer was significantly increased in essential hypertension (P less than 0.05). The amiloride-inhibitable rate of cell swelling in isotonic sodium propionate was also increased in HML from hypertensives. Amiloride (400 mumol/l) abolished the difference in cell volume within 1 min. These data show a functional swelling of HML in essential hypertension, probably due to an activation of the Na(+)-H+ exchanger. If also representative of smooth muscle cells, these findings could explain hypertensive vessel wall hypertrophy, in part, as functional cell swelling. 相似文献
996.
Proposal of a dose-response relationship between aluminium welding fume exposure and effect on the central nervous system. 总被引:1,自引:0,他引:1
Exposure to high levels of aluminium can affect the human central nervous system. Abnormalities of psychomotor function have been observed among haemodialysis patients with mean aluminium concentrations in serum of about 60 micrograms/l. According to our own data this corresponds to a urinary level of about 330 micrograms Al/l in aluminium-exposed welders without kidney failure. This post-shift urinary level of aluminium is estimated to be attained after 40 years of exposure to a welding fumes at an environmental concentration of approximately 1.6 mg/m3 of aluminium. An increased prevalence of effects on the nervous system was observed among welders exposed to aluminium fumes for more than 13 years. This finding supports the concept of cumulative toxicity due to aluminium exposure. On the basis of these observation, we suggest that the level of aluminium in welding fumes should not exceed 1 mg/m3. 相似文献
997.
Detection of frequent allelic loss on proximal chromosome 17q in sporadic breast carcinoma using microsatellite length polymorphisms. 总被引:20,自引:0,他引:20
P A Futreal P S?derkvist J R Marks J D Iglehart C Cochran J C Barrett R W Wiseman 《Cancer research》1992,52(9):2624-2627
Analyses of losses of heterozygosity and linkage studies have implicated a gene(s) on chromosome 17q in the genesis of sporadic and early-onset familial breast carcinomas, respectively. To define the critical region of 17q, we examined DNAs from a series of 20 sporadic breast carcinomas and corresponding blood samples for allelic losses of chromosome 17q using microsatellite length polymorphisms. With these highly informative markers (average heterozygosity, 0.73), we observed frequent deletions of 17q at several loci. We found that D17S250 was deleted in 50% (7 of 14), THRA1 in 79% (11 of 14), D17S579 in 59% (11 of 19), NME1 in 29% (5 of 17), MPO in 36% (4 of 11), and GH in 25% (4 of 16) in the tumor set examined. A common region of deletion was found that was flanked by D17S250 to D15S579. These markers have recently been localized to a 6-cM interval of proximal chromosome 17q in bands 17q11.2-q21 and map within the region of the early-onset familial breast cancer locus, implying that the same gene or genes may be involved in both sporadic and familial breast tumors. Thyroid hormone receptor alpha and retinoic acid receptor alpha are two potential candidate genes in this region. 相似文献
998.
H Kjaerulf-Jensen N Korsgaard H Lindeberg E Vigholt-S?rensen 《Pharmacology & toxicology》1992,71(4):302-304
The isolated spontaneously beating heart was used for comparing the effects of hypoxia and positive inotropic drugs on myocardial ultrastructure. Hypoxia gives a significant decrease in the volume fractions of mitochondrial cristae relative to the total mitochondrial volume (Vvmcristae) and a significant increase in the volume fraction of mitochondrial matrix relative to the total mitochondrial volume (Vvmmatrix), but changes in volume fractions of mitochondria (Vvmitochondria) and myofibrils (Vvmyofibrils) were absent. Significant changes in ultrastructure in hearts treated with dopamine (0.6 microM), dobutamine (90 nM), G-strofanthin (0.25 microM), xamoterol (32 nM) and isoprenaline (0.15 microM or 15 nM) were absent. Furthermore, myocardial effects in the isolated rabbit heart without exposure to any treatment showed a significantly decrease in oxygen consumption after 90 min. and a significant decrease in frequency of contractions after 120 min. perfusion time, but no change in contractility was seen. We conclude that this experimental model is useful in studies of positive inotropic drugs. 相似文献
999.
H Ostermann D Tsch?pe W Greber H W Meyer-Rüsenberg J van de Loo 《Thrombosis and haemostasis》1992,68(4):400-403
The fibrinolytic system was studied in 96 patients with type I diabetes mellitus. Patients were grouped according to their degree of retinopathy; 38 patients with no evidence of retinopathy, 28 patients with background retinopathy and 30 patients with proliferative retinopathy. Thirty healthy individuals served as controls. The basal fibrinolytic activity as measured by clot lysis time and t-PA activity was increased in diabetic patients. This was associated with low levels of plasminogen activator inhibitor. Increased levels of D-dimer in diabetic patients further indicate enhanced in vivo fibrinolysis. The increase in fibrinolytic activity was highest in diabetics without retinopathy, and decreased with increasing retinopathy. Endothelial release of t-PA after venous occlusion was not different between controls and all diabetic groups. These findings suggest that in type I diabetics the fibrinolytic system is in an activated state. With worsening of retinopathy this increase in fibrinolytic activity diminishes. 相似文献
1000.