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排序方式: 共有649条查询结果,搜索用时 31 毫秒
1.
SB Miranda† O Lupi‡ E Lucas† 《Journal of the European Academy of Dermatology and Venereology》2004,18(5):622-625
Pityriasis rosea (PR) is a relatively common disease although its aetiology has not yet been identified. It occurs worldwide and there is no racial susceptibility factor. It usually affects teenagers and young adults between 10 and 35 years of age. Typical PR is much easier to diagnose than the rare atypical forms. We report a rare case of vesicular PR in a black woman who had vesicular lesions limited to her palms and soles in addition to regular typical lesions. We devised an efficient oral erythromycin treatment for this patient. 相似文献
2.
K Sando M Hoki R Nezu Y Takagi A Okada 《JPEN. Journal of parenteral and enteral nutrition》1992,16(1):54-58
Selenium (Se) is not routinely included in total parenteral nutrition (TPN) solution; thus, patients receiving long-term TPN may be at risk of Se deficiency, which may cause fatal cardiomyopathy. Platelet glutathione peroxidase (GSH-Px) activity, as well as Se levels and GSH-Px activity in plasma and erythrocytes during prolonged TPN, was measured in six patients with chronic gastrointestinal disease. During the time course of TPN, Se administration was discontinued for 12 weeks, and then resupplemented for another 12 weeks. Before the study period, all Se indices had been maintained within the normal range. After discontinuation of Se supplementation, a significant decrease in platelet GSH-Px activity was observed after 1 week (from 64 +/- 7 [mean +/- SD] to 39 +/- 5 U/g of protein). After resupplementation, it increased after 1 week (from 44 +/- 9 to 65 +/- 10 U/g of protein). Plasma Se indices significantly changed within 3 weeks after withdrawal and reintroduction of Se (Se: from 136 +/- 28 to 75 +/- 14 and from 61 +/- 22 to 125 +/- 33 micrograms/L; GSH-Px: from 236 +/- 50 to 140 +/- 36 and from 128 +/- 32 to 220 +/- 64 U/L). Erythrocyte Se indices showed no significant changes during the study period. The results demonstrate that platelet GSH-Px activity is the most sensitive index of Se status in TPN patients. 相似文献
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进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml ̄(-1)诱导HL-60细胞发生凋亡,而阻断HR20细胞于G_1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml ̄(-1)处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G_1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关 相似文献
7.
Regulation of intestinal guanylate cyclase by the heat-stable enterotoxin of Escherichia coli (STa) and protein kinase C.
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J K Crane M S Wehner E J Bolen J J Sando J Linden R L Guerrant C L Sears 《Infection and immunity》1992,60(12):5004-5012
The heat-stable enterotoxin of Escherichia coli (STa) stimulates membrane-bound guanylate cyclase in intestinal epithelium and induces fluid and ion secretion. Using the T84 human colon carcinoma cell line as a model, we observed that phorbol esters markedly enhanced STa-stimulated cyclic GMP accumulation in T84 cells (C. S. Weikel, C. L. Spann, C. P. Chambers, J. K. Crane, J. Linden, and E. L. Hewlett, Infect. Immun. 58:1402-1407, 1990). In this study we document that the phorbol ester treatment increases 125I-STa-binding sites as well as membrane-bound guanylate cyclase activity in T84 cells and provide evidence that both effects are mediated by phosphorylation. Guanylate cyclase activity was increased approximately 50% in membranes prepared from intact T84 cells treated with phorbol-12,13-dibutyrate (beta-PDB) and after treatment of homogenates with beta-PDB in a manner dependent on ATP, MgCl2, and cytosol. Similarly, treatment of membranes with purified bovine brain protein kinase C in the presence of appropriate cofactors and beta-PDB resulted in an increase in STa-stimulated guanylate cyclase activity of about 70%. Likewise, the number of 125I-STa-binding sites was increased by about 25 to 40% in membranes prepared from intact cells or homogenates treated with beta-PDB; no effect on binding affinity (Kd = 0.15 nM) was noted. These experiments suggest that protein kinase C may phosphorylate the STa receptor-guanylate cyclase or a closely related protein and increase guanylate cyclase activity. The stimulatory effects of protein kinase C on STa-sensitive guanylate cyclase are opposite in direction to the profound inhibitory effects of the kinase on atrial natriuretic peptide-stimulated guanylate cyclase, demonstrating differential regulation by protein kinases within the guanylate cyclase-receptor family. 相似文献
8.
Needle biopsy of renal allografts: comparison of two techniques 总被引:2,自引:0,他引:2
Bogan ML; Kopecky KK; Kraft JL; Holladay AO; Filo RS; Leapman SB; Thomalla JV 《Radiology》1990,174(1):273-275
Two techniques for renal allograft biopsy were retrospectively evaluated to compare relative safety and efficacy. After ultrasound (US) localization of the kidney and biopsy with a hand-held 14-gauge cutting needle, an adequate specimen was obtained in 74 of 77 cases (96%). Major complications occurred in six of these 77 cases (8%). One hundred four biopsies were performed by using a smaller 18-gauge cutting needle with a spring-loaded biopsy "gun" and real-time US guidance. With this newer technique, specimens adequate for diagnosis were obtained in 99 biopsies (95%). There was a single major complication with this technique (1%). The 18-gauge needle with real-time US guidance yields comparably adequate specimens with a lower frequency of complications. 相似文献
9.
分娩期连续电子胎心监护用于胎儿评估 总被引:1,自引:0,他引:1
1背景 在美国,每4例孕妇中有3例在产群中及分娩时使用电子胎儿监护(EFM)(NCHS1993)。1989年,美国妇产科学院(ACOG1989)发表了一项声明,对于低危妊娠既可使用EFM,也可使用间断性胎心听诊;但是,美国预防保健委员会(USPSTF1989)和加拿大的定期健康检查委员会(CTFPHE1994)对高危妊娠仍保留使用EFM。尽管有人对EFM的效果和安全性表示担忧(Thacker 1987:Thacker 1995), 相似文献
10.
SB Grover N Midha M Gupta U Sharma VH Talib 《Journal of Medical Imaging and Radiation Oncology》2005,49(2):175-178
The clinical manifestations of chronic disseminated histoplasmosis are non-specific and resemble those of other chronic infections and malignancies. We report the radiographic, sonographic and contrast-enhanced CT appearances of histoplasmosis in an adult male with non-insulin dependent diabetes mellitus, who was HIV negative and presented with weight loss and pyrexia. Imaging studies simulated tuberculosis with mediastinal lymphadenopathy, bilateral fibrotic lung lesions, hepatomegaly and bilateral hypoattenuating adrenal enlargement, without clinical or laboratory evidence of hypoadrenalism. Computed tomography-guided fine-needle aspiration biopsy of adrenal glands revealed Histoplasma capsulatum. We report our experience to increase awareness of the imaging spectrum of disseminated histoplasmosis and its similarity to tuberculosis as, with increasing incidence of AIDS, the chances of these infections are likely to increase. Moreover, awareness of this entity is important because it is known that untreated disseminated histoplasmosis is fatal. 相似文献