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991.
Little information is available regarding the risk of human immunodeficiency virus type 1 (HIV-1) infection for patients transfused before routine anti-HIV-1 screening of blood donors was instituted in March 1985. A model was developed for estimating both the proportion and the number of transfusion recipients in the San Francisco Bay area who were infected by HIV-1 during each of the 7 years preceding routine donor screening for anti-HIV-1. The model is based on analysis of 1) donation histories of HIV-1-infected donors identified at the regional blood center; 2) HIV-1 seroprevalence estimates for homosexual and bisexual men in San Francisco; and 3) HIV-1 infection and survival rates for recipients traced by the Transfusion Safety Study and Irwin Memorial Blood Centers' Look Back Program. The incidence of transfusion-associated HIV-1 infection is estimated to have risen rapidly from the first occurrence in 1978 to a peak in late 1982 of approximately 1.1 percent per transfused unit. The decrease after 1982 coincided with the implementation of high-risk donor deferral measures. It is estimated that, overall, approximately 2135 transfusion recipients were infected with HIV-1 in the San Francisco region alone. This number suggests a higher prevalence of transfusion-associated HIV-1 infection than has been generally recognized and indicates the need for continued tracing of potentially exposed recipients. The data also strongly support the effectiveness of early donor education and self-exclusion measures and emphasize the importance of continued research and development in this area. 相似文献
992.
The In(Lu) gene, which inhibits the expression of Lutheran blood group antigens by red cells (RBCs), also down-regulates the expression of an 80-kD glycoprotein, In(Lu)-related p80, by both RBCs and a subset of white cells. This study examined the expression of multiple-RBC p80 epitopes by autosomal and X-linked recessive-type Lu(a-b-) RBCs in order to explore the relationship, if any, between expression of In(Lu)-related p80 and Lutheran antigens. Both autosomal and X-linked types of recessive Lu(a-b-) RBCs expressed near-normal to increased amounts of p80 antigens, as measured by radioimmunoassay. P80 from both types of recessive Lu(a-b-) RBCs had apparently normal molecular weight in denaturing polyacrylamide gels and showed normal sensitivity to digestion by trypsin and chymotrypsin. Thus, the absence of Lutheran antigens on recessive-type Lu(a-b-) RBCs is not associated with decreased or absent p80 antigens. Furthermore, the XS2 gene probably does not act via a mechanism similar to that of the In(Lu) gene, since the expression of p80 remains undiminished in X-linked recessive-type Lu(a-b-) RBCs. 相似文献
993.
The capacity of mitogen-responsive T cells to “home” to their tissue of origin, analyzed by means of chromosome markers 下载免费PDF全文
Lance and Taub (1) showed that when radioactively labeled lymphocytes were injected into a syngeneic mouse and the lymph node cells of this animal transferred to a second syngeneic recipient, the proportion of radioactivity found in the lymph node relative to the amount present in the spleen of the secondary recipient had increased markedly. The interpretation of this result was that some lymphocytes have the capacity to “home” to their organ of origin. The purpose of the experiments described here was to test the “homing” copacity of T cells by a method that did not involve radioactive labeling. It has been shown elsewhere that some or all mouse T cells are stimulated to divide in culture by the mitogens phytohemagglutinin (PHA) and concanavalin A (Con A) (2). We therefore elected to inject karyotypically distinct lymphocytes into syngeneic recipients and to follow their subsequent distribution by culture of lymph node and spleen cells of the recipient with PHA or Con A. In this manner the homing capacities of spleen and lymph node T cells could be determined, and furthermore, the effects of labeling with chromium-51 ((51)Cr) could be assayed with respect to the persistence of mitogen responsiveness in the injected cells. 相似文献
994.
Rajman I; Lip GY; Cramb R; Maxwell SR; Zarifis J; Beevers DG; Kendall MJ 《QJM : monthly journal of the Association of Physicians》1996,89(10):771-778
In a prospective longitudinal study in 17 women, we investigated the
effects of surgical menopause and subsequent oestrogen-only hormone
replacement therapy (HRT) on plasma concentrations of total cholesterol,
HDL cholesterol, LDL cholesterol, triglyceride and LDL subfractions
profile. Plasma LDL is a heterogeneous population of particles of varying
size, density and chemical composition. The predominance of small LDL
particles is a newly-recognized risk factor for coronary artery disease.
The LDL score is used to describe LDL subfractions profile and the greater
the score, the higher the proportion of small LDL particles. Six weeks
after hysterectomy and bilateral oopherectomy, total cholesterol and
triglyceride concentrations were significantly increased (p < 0.01) as
well as the LDL score (p < 0.05). After 6 weeks of oestrogen-only HRT,
total cholesterol concentration was significantly lower and HDL cholesterol
concentration significantly higher than before the treatment (p < 0.05).
At the same time, mean LDL score significantly increased and in none of the
women did LDL subfractions profile change favourably.
相似文献
995.
van der Vorst MM den Hartigh J Wildschut E Tibboel D Burggraaf J 《Critical care (London, England)》2007,11(5):R111
Introduction
The objective of the present study was to explore a continuous intravenous furosemide regimen that adapts to urine output in neonates treated with extracorporeal membrane oxygenation (ECMO). 相似文献996.
997.
MH Elvey H Pugh G Schaller G Dhotar B Patel MJ Oddy 《Annals of the Royal College of Surgeons of England》2014,96(5):381-385
Introduction
The cost of fragility fractures to the UK economy is predicted to reach £2.2 billion by 2025. We studied our hip fracture population to establish whether national guidelines on fragility fracture prevention were being followed, and whether high risk patients were identified and treated by local care services.Methods
Data on a consecutive series of trauma hip fracture admissions were collected prospectively over 14 months. National Institute for Health and Care Excellence (NICE) and National Osteoporosis Guideline Group (NOGG) recommendations and FRAX® risk calculations were applied to patients prior to their admission with a new hip fracture.Results
Overall, 94 patients were assessed against national guidelines. The mean population age was 77 years. Almost a quarter (22%) of patients had suffered a previous fragility fracture. The mean FRAX® ten-year probability of hip fracture was 7%. According to guidelines, 45% of the study population required treatment, 35% fulfilled criteria for investigation and reassessment, and 20% needed no further management. In practice, 27% received treatment, 4% had undergone dual energy x-ray absorptiometry and were untreated, and 69% had not been investigated and were untreated. In patients meeting intervention thresholds, only 33% of those who required treatment were receiving treatment in practice.Conclusions
In conjunction with NICE and NOGG recommendations, FRAX® was able to identify 80% of our fracture population as intermediate or high risk on the day of fracture. Correct management was evident in a third of cases with a pattern of inferior guideline compliance seen in a London population. There remains a lack of clarity over the duty of care in fragility fracture prevention. 相似文献998.
Candida species (spp) are commensal yeast that can only instigate oral infection (oral candidosis – OC) when there is an underlying predisposing condition in the host. We investigated four controversial topics on OC: (i) How can a microbiological determination of OC be made as Candida spp. are commensal yeasts and not all of them form hyphae or pseudohyphae during infection? (ii) Is median rhomboid glossitis (MRG) a manifestation of candidal infection? (iii) Can candidal infection cause palate papillary hyperplasia (PPH)? (iv) What is the best therapeutic treatment for denture‐associated erythematous stomatitis (DAES)? Results from extensive literature searches, including a systematic review, suggested the following: (i) the diagnosis of OC merely on the basis of the presence of yeasts is an oversimplification of a complex process. No convincing evidence of a single test or method better able to discriminate the transition from candidal saprophytism to pathogenicity has been reported in the literature; (ii–iii) conclusive evidence of a direct aetiopathogenic relationship between MRG and PPH and candidal infection has not been found; and (iv) only limited evidence is available for any DAES treatment, thus making it impossible to make strong therapeutic recommendations. 相似文献
999.
N Choudhury I Amer M Daniels MJ Wareing 《Annals of the Royal College of Surgeons of England》2013,95(1):34-36
Introduction
Aural microsuction is a common ear, nose and throat procedure used in the outpatient setting. Some patients, however, find it difficult to tolerate owing to discomfort, pain or noise. This study evaluated the effect of audiovisual distraction on patients’ pain perception and overall satisfaction.Methods
A prospective study was conducted for patients attending our aural care clinic requiring aural toileting of bilateral mastoid cavities over a three-month period. All microsuction was performed by a single clinical nurse specialist. Any patients with active infection were excluded. For each patient, during microsuction of one ear, they watched the procedure on a television screen while for the other ear they did not view the procedure. All patients received the same real time explanations during microsuction of both ears. After the procedure, each patient completed a visual analogue scale (VAS) to rate the pain they experienced for each ear, with and without access to the television screen. They also documented their preference and reasons why.Results
A total of 37 patients were included in the study. The mean pain score for patients viewing the procedure was 2.43 compared with a mean of 3.48 for patients with no television view. This difference in patients’ pain perception was statistically lower in the group who observed the procedure on the television (p=0.003), consistent with the majority of patients reporting a preference to viewing their procedure (65%).Conclusions
Audiovisual distraction significantly lowered patients’ VAS pain scores during aural microsuction. This simple intervention can therefore reduce patients’ perceived pain and help improve acceptance of this procedure. 相似文献1000.
S Mukhtar BE Ayres R Issa MJ Swinn MJA Perry 《Annals of the Royal College of Surgeons of England》2013,95(3):200-206