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91.
92.
Heterogeneity of anti-U demonstrable by the use of papain-treated red cells   总被引:1,自引:0,他引:1  
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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94.

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   
95.

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   
96.
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   
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99.
Purpose: To assess the validation of a novel control selection design by comparing the consistency between the new design and a routine design in a large case-control study that was incorporated into a nationwide mortality survey in China.Methods: A nationwide mortality study was conducted during 1989-1991. Surviving spouses or other relatives of all adults who died during 1986-1988 provided detailed information about their own as well as the deceased person''s smoking history. In this study, 130,079 males who died of various smoking-related cancers at age 35 or over were taken as cases, while 103,248 male surviving spouses (same age range with cases) of women who died during the same period and 49,331 males who died from causes other than those related to smoking were used as control group 1 and control group 2, respectively. Consistency in the results when comparing cases with each of the control groups was assessed.Results: Consistency in the results was observed in the analyses using different control groups although cancer deaths varied with region and age. Equivalence could be ascertained using a 15% criterion in most cancer deaths which had high death rates in urban areas, but they were uncertain for most cancers in rural areas irrespective of whether the hypothesis testing showed significant differences or not.Conclusions: Sex-matched living spouse control design as an alternative control selection for a case-control study is valid and feasible, and the basic principles of the equivalence study are also supported by epidemiological survey data.  相似文献   
100.
背景及目的:Denosumab为一种人类单克隆抗体,它是核因子B配体(TANK)的受体激活剂(RANKL),RANKL,能够阻断该受体与RANK结合,从而抑制破骨细胞的生长及作用,减少骨的再吸收,增强骨密度.本研究分析了该药物对绝经后妇女骨质疏松症的预防作用.  相似文献   
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