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91.
When red cells (RBCs) are treated with papain, one form of the U antigen, which we have named UPS (U papain-sensitive), is almost completely removed or denatured. A second form, UPR (U papain-resistant), remains unaltered on the treated RBCs. Tests on 42 examples of anti-U showed that two contained only anti-UPS, 19 contained only -UPR, and 21 contained separable -UPS and -UPR. In those sera containing both antibodies, anti-UPR was always the stronger of the two. These findings suggest 1) that UPS is located on the Ss sialoglycoprotein (glycophorin B) at a position distal to a papain-sensitive site or that the cleavage point is within the portion of the SGP that comprises UPS, and 2) that UPR is located between the papain-sensitive site and the RBC membrane. The UPS determinant was not denatured by neuraminidase, L-cysteine, trypsin, ficin, or alpha-chymotrypsin, and it was only partially denatured by pronase. The finding that RBCs treated with para-chloromercuribenzoic acid or para-chloromercuriphenyl sulfonic acid did not react with anti-UPR but did continue to react with anti-UPS suggests that the in situ configuration of UPR, but not UPS, is dependent on the presence of one or more disulfide bonds. RBCs of the S-s-U+(weak) phenotype were shown to carry markedly reduced amounts of both UPS and UPR. 相似文献
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93.
Cleland JG Coletta AP Torabi A Ahmed D Clark AL 《European journal of heart failure》2010,12(11):1261-1264
This article provides information and a commentary on key trials relevant to the pathophysiology, prevention, and treatment of heart failure (HF) presented at the annual meeting of the European Society of Cardiology held in Stockholm in 2010. Unpublished reports should be considered as preliminary, since analyses may change in the final publication. The SHIFT study supports the use of ivabradine in patients with HF due to left ventricular systolic dysfunction and resting sinus rhythm rate ≥70 b.p.m. despite treatment with beta-blockers or where beta-blockers are contra-indicated. Results from PEARL-HF suggest that the potassium binding polymer RLY5016 may be useful for both prevention and treatment of hyperkalaemia in HF patients with or without concomitant chronic kidney disease. The STAR-heart study provides encouraging observational data about the potential for intracoronary stem cell transplantation in patients with HF. Results from HEBE-III showed no effect of erythropoietin on ejection fraction measured 6 weeks post-MI; although there were fewer cardiovascular events in patients assigned to erythropoietin, the study was too small to provide conclusive evidence of effect. 相似文献
94.
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Sensenig R Kalghatgi S Cerchar E Fridman G Shereshevsky A Torabi B Arjunan KP Podolsky E Fridman A Friedman G Azizkhan-Clifford J Brooks AD 《Annals of biomedical engineering》2011,39(2):674-687
Non-thermal atmospheric pressure dielectric barrier discharge (DBD) plasma may provide a novel approach to treat malignancies via induction of apoptosis. The purpose of this study was to evaluate the potential of DBD plasma to induce apoptosis in melanoma cells. Melanoma cells were exposed to plasma at doses that did not induce necrosis, and cell viability and apoptotic activity were evaluated by Trypan blue exclusion test, Annexin-V/PI staining, caspase-3 cleavage, and TUNEL? analysis. Trypan blue staining revealed that non-thermal plasma treatment significantly decreased the viability of cells in a dose-dependent manner 3 and 24 h after plasma treatment. Annexin-V/PI staining revealed a significant increase in apoptosis in plasma-treated cells at 24, 48, and 72 h post-treatment (p < 0.001). Caspase-3 cleavage was observed 48 h post-plasma treatment at a dose of 15 J/cm(2). TUNEL? analysis of plasma-treated cells demonstrated an increase in apoptosis at 48 and 72 h post-treatment (p < 0.001) at a dose of 15 J/cm(2). Pre-treatment with N-acetyl-L: -cysteine (NAC), an intracellular reactive oxygen species (ROS) scavenger, significantly decreased apoptosis in plasma-treated cells at 5 and 15 J/cm(2). Plasma treatment induces apoptosis in melanoma cells through a pathway that appears to be dependent on production of intracellular ROS. DBD plasma production of intracellular ROS leads to dose-dependent DNA damage in melanoma cells, detected by γ-H2AX, which was completely abrogated by pre-treating cells with ROS scavenger, NAC. Plasma-induced DNA damage in turn may lead to the observed plasma-induced apoptosis. Since plasma is non-thermal, it may be used to selectively treat malignancies. 相似文献
96.
SR Kulkarni MS Gohel RA Bulbulia MR Whyman KR Poskitt 《Annals of the Royal College of Surgeons of England》2009,91(3):210-213
INTRODUCTION
Early carotid endarterectomy (CEA) in symptomatic patients may prevent repeat cerebral events. This study investigates the relationship between waiting time for CEA and the incidence of repeat cerebral events prior to surgery in symptomatic patients.PATIENTS AND METHODS
A prospective database of consecutive patients undergoing CEA between January 2002 and December 2006 was reviewed. Repeat event rates prior to surgery were calculated using Kaplan–Meier analysis and predictive factors identified using Cox regression analysis.RESULTS
A total of 118 patients underwent CEA for non-disabling stroke, TIA and amaurosis fugax. Repeat cerebral events occurred in 34 of 118 (29%) patients at a median 51 days (range, 2–360 days) after the first event. The estimated risk of repeat events was 2% at 7 days and 9% at 1 month after first event (Kaplan–Meier survival analysis). Age (HR 1.059; 95% CI 1.014–1.106; P = 0.009] was identified as a predictor of repeat events. Patients underwent surgery at median 97 days (range, 7–621 days) after the first event. Eleven of 60 (18%) patients waiting ≤?97 days for surgery and 23 of 58 (40%) patients waiting >?97 days had repeat events. (P = 0.011, chi-squared test).CONCLUSIONS
Delays in surgery should be reduced in order to minimise repeat cerebral events in patients with symptomatic carotid stenosis, particularly in the elderly population. 相似文献97.
Background
Hepatitis B virus (HBV) infection is an important occupational risk in health care workers (HCW). In spite of HBV vaccine availability in Armed Forces, the high prevalence of HBV infection in HCW continues to be a problem. The study was undertaken to study the HBV vaccine-compliance among HCW.Methods
A cross-sectional study was conducted at a tertiary care hospital. HCW were requested to fill up the pre set questionnaire to assess the HBV vaccination coverage.Result
Amongst 254 HCW, only 57.7% were vaccinated against HBV. The vaccine compliance was lowest among housekeeping professionals. The mean age at vaccination was high (30.5 years). Amongst the vaccine non-compliant subjects, 34.3% were above 30 years of age. 32.2% HCW completed primary vaccination after spending more than 10 years in the profession. Accessibility of HBV vaccine, knowledge and perception of HBV risk were important factors in vaccine non-compliance.Conclusion
Due to low and delayed HBV vaccine-compliance, HCW continue to be at the risk of occupational HBV. Health education highlighting occupational risk of HBV, accessibility of vaccine and mandatory vaccination of HCW is recommended to increase HBV vaccine compliance among HCW.Key Words: Health care workers, Hepatitis B virus, Occupational risk, Hepatitis B vaccine 相似文献98.
Background: Management of patients with cleft lip and palate (CLP) includes orthodontic treatment prior to bone grafting. Palatal expansion is done using slow or rapid palatal expansions (RPE). Controversy still exists regarding choice of expansion appliances used. This study was conducted to find out whether the Quad helix appliance represents a reasonable alternative to using conventional rapid maxillary expansion appliance among cleft lip and palate patients. 相似文献
99.