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991.
疟疾感染与单采血浆还输血细胞关系的研究 总被引:4,自引:0,他引:4
本文探讨了永清县人群疟疾感染与供血的关系。在249例疟疾中,244例(98.0%)为单采血浆还输血细胞(简称单采浆)供血者,5例(2.0%)为受血者。人群疟疾发病率与单采血浆率呈显著正相关,而与人群总供血率和供全血率无相关关系;不同年龄组人群疟疾发病率与该年龄组人群单采浆率呈显著正相关;病例对照调查结果表明,单采浆是疟疾发病的危险因素;单纯单采浆供血者疟疾发病率为33.7%,既单采血浆又供全血者为15.76%,无供血史者为0.0014%,单纯供全血者无人发病。对单采浆血站调查发现,在采血、离心分浆和血细胞还输过程中存在血液交叉污染环节,血站停业后疟疾疫情平息。认为永清县人群疟疾感染与单采浆有关。 相似文献
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Gibney GT Panhuysen CI So JC Ma ES Ha SY Li CK Lee AC Li CK Yuen HL Lau YL Johnson DM Farrell JJ Bisbee AB Farrer LA Steinberg MH Chan LC Chui DH 《American journal of hematology》2008,83(6):458-464
Enhanced fetal hemoglobin (Hb F) production can partially compensate for the lack of adult hemoglobin (Hb A) in patients with beta-thalassemia major or intermedia, and ameliorate the clinical severity of these diseases. To further elucidate factors governing Hb F levels, we evaluated demographic, clinical, laboratory, and genetic characteristics in 241 unrelated adult beta-thalassemia carriers in Hong Kong. They had wide variations in Hb F and F-cell numbers skewing toward higher levels. Individuals who coinherited the Xmn IT-allele in the (G)gamma-globin gene promoter had higher Hb F and more F-cells compared with those lacking the Xmn I T-allele. However, both groups exhibited a similarly wide spread of Hb F and F-cells. The correlation of Hb F and F-cells corresponded well to both linear and exponential models, suggesting multiple mechanisms for Hb F augmentation. The heritabilities of Hb F and F-cells were calculated in 66 families (111 parents who were beta-thalassemia carriers and 82 asymptomatic offspring) to be 0.7 to 0.9. The Xmn I polymorphism accounted for 9% of the Hb F and 13% of the F-cell heritabilities. These results suggest that these family members are well suited for genome wide association studies that will identify genetic loci regulating Hb F production, and likely novel pharmacological targets for reactivating Hb F production in adults. 相似文献
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Retinal vessel diameter and cardiovascular mortality: pooled data analysis from two older populations. 总被引:1,自引:1,他引:1
Jie Jin Wang Gerald Liew Ronald Klein Elena Rochtchina Michael D Knudtson Barbara E K Klein Tien Yin Wong George Burlutsky Paul Mitchell 《European heart journal》2007,28(16):1984-1992
AIMS: The retinal microvasculature may reflect pre-clinical changes in the cerebral and coronary microcirculations. We assessed whether smaller retinal arterioles and larger venules predicted coronary heart disease (CHD)- and stroke-mortality. METHODS AND RESULTS: We pooled data from the Beaver Dam Eye Study (n = 4926, aged 43-86) and the Blue Mountains Eye Study (n = 3654, aged 49-97). Retinal vessel diameters were measured from digitized retinal photographs. Change point models were used to assess and document the existence of threshold effects. We defined smaller arterioles as diameters within the narrowest quintile and larger venules as diameters within the widest quintile, with other quintiles as the reference. Of 8550 participants, 7494 (88%) with complete data were included, of whom 653 died from CHD and 299 from stroke over 10-12 years follow-up. After multivariable adjustment, each standard deviation (SD) increase in arteriolar diameter, or SD decrease in venular diameter, was not found to be significantly associated with either CHD-mortality or stroke-mortality. However, smaller arterioles [hazard ratio (HR) 1.34, 95% confidence interval (CI) 1.11-1.62] and larger venules (HR 1.24, CI 1.02-1.52), predicted increased risk of CHD-mortality. These associations were mainly evident among persons aged 43-69 (smaller arterioles: HR 1.70, CI 1.27-2.28; larger venules: HR 1.41, CI 1.06-1.89). Smaller arterioles (HR 1.64, CI 1.00-2.67) and larger venules (HR 1.53, CI 0.94-2.47) were also associated with an increased risk of stroke-mortality among persons aged 43-69. CONCLUSION: Retinal vessel diameter may predict risk of CHD and stroke deaths in middle-aged persons. 相似文献
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Prognostic significances of tumor-infiltrating S-100 positive dendritic cells and lymphocytes in patients with hepatocellular carcinoma 总被引:8,自引:0,他引:8
BACKGROUND/AIMS: To investigate the prognostic significances of dendritic cells and lymphocytes infiltration in hepatocellular carcinoma. METHODOLOGY: The clinicopathological and follow-up data of 44 patients with hepatocellular carcinoma, who underwent curative resection of tumor in our hospital from January 1995 to July 1996, were collected. Immunohistochemical staining was employed to detect the S-100 positive dendritic cells in the tumor tissue, and lymphocytes infiltration was evaluated simultaneously. The relationship of the tumor-infiltrating dendritic cells and lymphocytes to the postoperative recurrence-free time and survival rate was analyzed. RESULTS: Either the tumor-infiltrating dendritic cells or the tumor-infiltrating lymphocytes alone had no significant relationship to the postoperative recurrence-free time and survival rate. By taking into consideration both tumor-infiltrating dendritic cells and lymphocytes simultaneously, the patients were classified into two groups. Group A included patients having dendritic cell counts > or = 20 cells/10 high power fields together with positive lymphocytes infiltration (n = 17), and group B consisted of patients having dendritic cell count > or = 20 cells/10 high power fields but with negative lymphocytes infiltration or dendritic cell count < 20 cells/10 high power fields with either positive or negative lymphocytes infiltration (n = 27). There were no significant differences in clinicopathological features between two groups. The recurrence-free time was markedly longer in group A as compared with group B, with a median time of 21.6 months for group A and 4.1 months for group B (P < 0.05). The 1-, 3-, 4-year survival rates were significantly greater in group A than those in group B, being 83.5% vs. 42.2%, 61.8% vs. 28.4% and 48.7% vs. 23.0%, respectively (P < 0.01). CONCLUSIONS: Marked infiltration of dendritic cells together with lymphocytes in tumor tissue was closely related to the improved clinical prognosis in patients with hepatocellular carcinoma, and represented as an independent prognostic factor. 相似文献