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761.
The c100 hepatitis C virus (HCV) enzyme-linked immunosorbent assay (ELISA) has been used to screen blood donors to prevent transfusion-associated non-A,non-B hepatitis. This test is not specific, and only about 25 percent of c100 HCV ELISA-positive blood samples appear to transmit hepatitis C. However, the intensity of the ELISA (sample/cutoff ratio [S/C], greater than 2) could identify a subpopulation of donors that are at high risk for transmitting hepatitis. Blood samples from 20,186 volunteer blood donors at a Canadian Red Cross blood transfusion center were screened for antibodies to HCV using the c100 HCV ELISA. Fifty-nine (0.3%) of these donors were repeatably reactive on ELISA. When their samples were tested with the c100 recombinant immunoblot assay (RIBA) and second-generation RIBA (RIBA-2), 26 (44%) and 31 (52%) samples, respectively, were found to be positive. Thirty-three of the 59 ELISA-reactive donors had an S/C greater than 2. Of these 33 donors, 30 (91%) had elevated alanine aminotransferase (ALT), 27 (82%) were RIBA-2 positive, and 22 (67%) had risk factors for hepatitis. In contrast, of the 26 ELISA-reactive donors with S/C less than 2, only 7 (27%) had elevated ALT, and 4 (15%) were RIBA-2 positive and also had high risk factors for hepatitis. Thus, while the HCV ELISA may lack specificity, its intensity can serve to identify a subgroup of donors that are at high risk for transmitting hepatitis.  相似文献   
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763.

Objectives

A measure used for assessing the effectiveness of HIV care and comparing clinical centres is the proportion of people starting antiretroviral therapy (ART) with viral suppression (VS) after 1 year. We propose a method that adjusts for patients’ demographic characteristics, and visually compares this measure between different sites accounting for centre size.

Methods

We analysed viral load measurements for UK Collaborative HIV Cohort (UK CHIC) patients starting ART between 2006 and 2013. We used logistic regression to estimate the proportion with VS after 1 year of ART adjusted for patient mix (in terms of age and a combined gender/ethnicity/acquisition mode variable) and calendar year. We compared outcomes between centres using funnel plots which account for centre size.

Results

The overall proportion of the cohort with VS 1 year after starting ART was 90% and increased from 83% to 93% between 2006 and 2013. VS was lower in younger individuals. White men who have sex with men (MSM) had the highest (94%), and black African (81%) and white (82%) heterosexual women the lowest proportions achieving VS. Comparing the unadjusted funnel plot with the adjusted, there were movements of some centres from outside to inside the 95% contour limits, which was largely explained by the patient mix of these centres.

Conclusions

VS 1 year after ART start was associated with demographic characteristics and centre size; therefore, to compare the performances of centres, adjustment for these factors is required. Adjusted funnel plot is an effective tool which accounts for both the demographic characteristics and the centre size. Social factors, rather than treatment decisions within the control of the centres, may drive differences in outcomes.  相似文献   
764.
肝细胞生长因子拮抗剂NK4抑制肿瘤的机制   总被引:1,自引:0,他引:1  
0 引言 肝细胞生长因子(hepatocyte growth factor,HGF)是由间质细胞产生的细胞因子,作用于肿瘤细胞表面的跨膜受体c-Met蛋白,引起肿瘤细胞的浸润、转移,而且HGF对新生血管的生成起促进作用.1997年Date等[1]用胰弹性蛋白酶对重组人HGF进行消化裂解,发现了一种新的全面拮抗HGF生物活性功能的拮抗剂-NK4.  相似文献   
765.
766.
The objective of this study is to determine if there was a difference in rate of post-transplantation urinary tract infection (UTI) in patients who have an indwelling catheter inserted using sterile versus clean technique. UTI is the most common nosocomial infection in the post-transplantation period. We aim to describe risk factors associated with postoperative UTI in our institution and determine if there was a difference between those who have an indwelling catheter inserted using sterile versus clean technique. Risk factors for UTIs can be divided into recipient, donor, and procedure related factors. While an indwelling urinary catheter increases the risk of infection, it is vital for post-operative fluid balance monitoring. Given the morbidity of UTIs in transplant recipients, a number of studies have investigated modifiable risk factors; however, investigation of the technique of indwelling catheter insertion at the time of renal transplantation is yet to be examined. A retrospective analysis of a contemporaneously maintained database was performed of renal transplant recipients over a 2-year period from 2019–2021. Patients were divided into sterile versus clean technique, defined as the use of sterile gloves, gown and fenestrated drape following a surgical scrub, or sterile gloves alone following the use of alcohol-based hand sanitiser respectively. A p value of <0.05 was considered statistically significant. One hundred sixty-nine patients were included in analysis, with 31 UTIs (18.3%) within 30 days of renal transplantation. Female gender and autosomal dominant polycystic kidney disease were associated with a higher rate of UTI. One hundred twenty-three patients had a catheter inserted via sterile technique, and 46 with clean technique, with no significant difference in rate of post-operative UTI (p = 0.52). Inserting an indwelling catheter either by sterile or clean technique at the time of renal transplantation was not associated with the rate of postoperative UTI within 30 days.  相似文献   
767.
We report on five SARS-CoV-2 congregate setting outbreaks at U.S. Operation Allies Welcome Safe Havens/military facilities. Outbreak data were collected, and attack rates were calculated for various populations. Even in vaccinated populations, there was rapid spread, illustrating the importance of institutional prevention and mitigation policies in congregate settings.  相似文献   
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770.
Crown fractures and luxations occur most frequently of all dental injuries. An appropriate treatment plan after an injury is important for a good prognosis. Guidelines are useful for delivering the best care possible in an efficient manner. The International Association of Dental Traumatology (IADT) has developed a consensus statement after a review of the dental literature and group discussions. Experienced researchers and clinicians from various specialties were included in the group. In cases where the data did not appear conclusive, recommendations were based on the consensus opinion of the IADT board members. The guidelines represent the current best evidence, based on literature research and professional opinion. In this first article of three, the IADT Guidelines for management of fractures and luxations of permanent teeth will be presented.  相似文献   
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