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31.
SUNG-GOO CHANG CHUL-SOO KIM SEUNG HYUN JEON YOUN-WHA KIM BO YOUL CHOI 《International journal of urology》2006,13(2):122-126
AIM: To evaluate the cause of elevated prostate-specific antigen (PSA) in patients with transrectal needle biopsy negative for prostate cancer. METHODS: Serum PSA concentration, prostate volume, and pathologic findings were examined in 223 patients with negative biopsy for prostate cancer. The degree of prostate inflammation was determined by the extent and degree of inflammation shown by biopsy specimens and is expressed as an inflammation score (range: 0-36). RESULTS: A significant correlation was found between PSA concentration and prostate total volume (P=0.0001). Prostate chronic inflammation showed no correlation with PSA concentration (P=0.485, F=0.488). After allocating patients to normal PSA (4 ng/mL) groups, we found that serum PSA concentrations in both groups were predominantly affected by prostate total volume. CONCLUSIONS: An increase in prostate volume appears to be the major contributor to a high serum PSA concentration in patients with negative biopsy for prostate cancer. However, in contrast to previous reports, there was no correlation between the degree of prostate chronic inflammation and serum PSA concentrations. 相似文献
32.
Abstract: A pulsatile impeller assist heart and a total heart were tested as a chronic left ventricular assist device in 5 calves and an acute biventricular assist device in 4 pigs respectively, to evaluate their blood compatibility. During the left ventricular assist experiments, the indicators for hemolysis, thrombogenesis, renal dysfunction, and hepatic dysfunction were measured preoperatively, at the beginning of the pumping, 6 h postoperatively, and every following day. The results demonstrated that the impeller assist heart causes no severe blood damage nor organ dysfunction in the experiments lasting up to 11 days. In biventricular assist experiments, the number of red blood cells, white blood cells, platelets, and the he-matocrit, hemoglobin, free hemoglobin, and lactate dehy-drogenase levels were tested preoperatively at the beginning of the pumping and every 2 h postoperatively. The data remained in acceptable ranges during experiments lasting 6 h. It is confirmed that the authors' impeller assist heart and total heart have the advantages of simplicity, implantability, and pulsatility with good blood compatibility. 相似文献
33.
34.
TF Leung WC Tsoi CK Li KW Chik MMK Shing PMP Yuen 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(6):705-777
We describe a 15-y-old girl with Fechtner-like syndrome, who is the first Chinese reported to have this rare syndrome. She presented with left homonymous hemianopia and neuroimaging revealed haemorrhage in both parietal and occipital lobes. Peripheral blood smear showed macrothrombocytopenia and intracytoplasmic inclusion bodies inside leucocytes. Thrombocytopenia and proteinuria responded to intravenous immunoglobulin and pulsed methylprednisolone. This case illustrates that life-threatening haemorrhage can occur in patients with Fechtner syndrome. Although there was no effective treatment reported in the literature, high dose steroid and immunoglobulin seemed to be useful in our patient. Our patient also had nephritic-nephrotic syndrome with renal insufficiency, which is unusual in adolescent female patients. 相似文献
35.
硒和/或维生素E预防大鼠内皮细胞损伤的实验研究 总被引:15,自引:1,他引:14
用含硒(Se0.5mg/kg)和/或维生素E(VE0.6g/kg)的高脂饲料喂养成年雄性Wistar大鼠12周。结果:高脂对照组大鼠血浆前列腺素Flα(6-酮-PGF1α)水平下降,而血清脂质过氧化物(LPO)、血浆血栓素(TXB2)及内皮素(ET)水平上升;补Se、VE及Se+VE可明显降低大鼠血清LPO、血浆TXB2、ET及TXB2/6-酮-PGF1α比值。同时,除了明显提高血浆谷胱甘肽过氧化物酶(GSH-Px)活力外,血浆6-酮-PGF1α浓度明显升高。实验提示,Se和/或VE有调节花生四烯酸代谢及保护内皮细胞的作用。 相似文献
36.
The effect of Cyclosporin A (CsA) on prostaglandin E2 (PGE2 ) production in human gingival fibroblasts challenged with tumor necrosis factor alpha (TNF-α) was studied. TNF-α (1-100 ng/ml) dose-dependently stimulated PGE2 ; formation in 24 h cultures. CsA (1-100 ng/ml) did not induce PGE2 ; formation itself but potentiated TNF-α induced PGE; formation in gingival fibroblasts in a manner dependent on the concentrations of both CsA and TNF-α. TNF-α (10 ng/ml) stimulated the release of [3 H]-arachidonic acid (A.A) from prelabelled fibroblasts that was potentiated by CsA (100 ng/ml). Addition of exogenous unlabelled AA (5-20 μM/ml) to the cells resulted in enhanced PGE2 : formation that was not potentiated by CsA (100 ng/mi). Furthermore. CsA (100 ng/ml) did not further increase the level of cyclooxygenase-2 mRNA induced by TNF-α (10 ng/ml). although PGE2 formation was enhanced. The results indicate that CsA and TNF-α act in concert on PGE2 formation in gingival fibroblasts. which may be of importance in the pathogenesis of gingival overgrowth induced by the drug. 相似文献
37.
Chronic vitamin E treatment prevents defective endothelium-dependent relaxation in diabetic rat aorta 总被引:2,自引:2,他引:0
Summary We examined the effect in rats of 2 months of streptozotocin-induced diabetes mellitus on relaxation and contraction of aortas in vitro. A further diabetic group was treated from time of diabetes induction with a 1% dietary supplement of vitamin E. Diabetes caused a 26.5% deficit (p<0.001) in maximum endothelium-dependent relaxation to acetylcholine in phenylephrine-precontracted aortas. This was 64.3% attenuated (p<0.01) by vitamin E treatment; maximum relaxation was not significantly altered compared to non-diabetic rats. Vitamin E treatment of non-diabetic rats did not significantly affect acetylcholine-induced relaxation. Diabetes or treatment did not significantly alter acetylcholine sensitivity. Endothelium-independent relaxation response to glyceryl trinitrate was not affected by diabetes or vitamin E treatment, indicating that vascular smooth muscle responses to nitric oxide remained unaltered. There was a 35.4% reduction in the maximum contractile response to phenylephrine with diabetes (p<0.05) which was unaffected by vitamin E treatment. The data suggest that the chronic deficit in nitric oxide-mediated endothelium-dependent relaxation in diabetes depends largely upon excess activity of reactive oxygen species. Treatment with vitamin E to increase free radical scavenging specifically protected vascular endothelium although it had no effect on deficits in vascular smooth muscle contractile responses.Abbreviations NO
Nitric oxide
- ARI
aldose reductase inhibitor
- ACH
acetylcholine
- GTN
glyceryl trinitrate
- GSH
reduced form of glutathione
- EC50
effective concentration for 50% of the maximal response 相似文献
38.
39.
用小鼠胎肝细胞体外血浆凝块培养红系集落(Erythroid colong formig unit inculturc,E-CFUc)方法,以红细胞生成素(Erythropoietin,EPO)850323为标准试剂,测定正常人、贫血病人血清EPO浓度。实验用妊娠13~15d小鼠胎肝细胞。血清均经透析处理,培养液中加量最大不超过10%。EPO(850323)在培养液中浓度为2.5~100mU/ml。血清EPO(mU/ml)测定结果:28例正常人为48.O±17.7,12例再生障碍性贫血病人为946~>10000,1例巨幼细胞性贫血病人为500,1例缺铁性贫血病人为400和18例慢性肾功能衰竭病人则为94.2±87.6。结果表明:贫血病因对血清EPO浓度有影响。 相似文献
40.
Influence of age on faecal carriage of P-fimbriated Escherichia coli and other gram-negative bacteria in hospitalized neonates 总被引:3,自引:0,他引:3
K. Tullus B. Fryklund B. Berglund G. Kllenius L. G. Burman 《The Journal of hospital infection》1988,11(4):349-356
The aerobic faecal flora of 953 infants aged over 5 days was studied on discharge from 22 neonatal wards in Swedish hospitals. Klebsiella/enterobacter was isolated from 74% of infants and dominated the aerobic gram-negative flora in 19 wards. Escherichia coli was carried by 42% and showed a slight dominance in two wards. Initially klebsiella/enterobacter dominated the flora but became increasingly mixed with and taken over by E. coli, carriage increasing from 21% in infants discharged after 5-7 days to 57% after 3 weeks or later. Among infants with E. coli, P-fimbriated strains were demonstrated in 23% (range 0-67) and were independent of age. Occasional clustering of such strains was observed in 3/22 wards during the study period. It is postulated that the general and local colonization patterns observed reflect differences between individual strains of E. coli and klebsiella in both their capacity for transmission and their persistence in the newborn gut. The role of P-fimbriae in intestinal colonization of neonates by E. coli was, however, not supported. 相似文献