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41.
白介素与溃疡性结肠炎 总被引:17,自引:1,他引:17
近年来对白介素(interleukin,IL)和溃疡性结肠炎(ulcerative colitis,UC)的研究取得了很大进展,我们通过总结整理以前有关IL和UC的文献,概括出IL的产生和在UC发病及病理变化中的作用机制:IL-1直接介导了UC初期阶段炎症的发生:IL-8、IL-6直接促进炎性细胞过度分泌和/或抑制了炎性细胞的凋亡,IL-2分泌减少导致免疫系统内细胞间网络调节失衡, 使局部炎症介质和自由基释放,引起细胞毒作用,IL主要通过影响机体整体和/或局部免疫系统的功能介导UC的产生,并与UC的迁延难愈和反复发作有关. 相似文献
42.
Objectives
Human leukocyte antigen (HLA)‐B*5701 is strongly associated with developing a hypersensitivity reaction to abacavir (ABC) in White and Hispanic subjects. Across the UK, limited data exist on HLA‐B*5701 prevalence in HIV‐1‐infected subjects. We determined HLA‐B*5701 prevalence in the general HIV‐1‐infected population and in specific ethnic groups, particularly Black Africans who, in general, exhibit greater genetic diversity. We also compared HLA‐B*5701 results obtained from local laboratories with those from a central provider.Design and methods
Multi‐centre, observational study. All HIV‐1‐infected adult individuals receiving care at participating centres were eligible, irrespective of treatment status or prior exposure to ABC. Subjects provided samples for HLA‐B*5701 assessment by both local (blood) and central laboratories (buccal swabs). HLA‐B*5701 prevalence was adjusted to represent the ethnic group composition of the general UK population, and by main ethnic group.Results
From eight UK centres, 1494 subjects [618 (41%) White, 770 (52%) Black] were recruited. Eighty‐nine per cent of Black subjects reported an immediate country of origin in Africa. Overall adjusted HLA‐B*5701 prevalence was 4.55% [95% confidence interval (CI) 3.49% to 5.60%]. Among White subjects, prevalence was 7.93% (CI 5.80% to 10.06%). Among Black subjects, only two (both Ugandan) were HLA‐B*5701 positive giving a rate of 0.26% (CI 0.07% to 0.94%).Conclusions
HLA‐B*5701 prevalence was similar to previously reported rates in White HIV‐infected subjects but considerably lower than that reported in Black HIV‐1‐infected subjects, as a result of the large proportion of Black African subjects. 相似文献43.
目前有些抗肿瘤药物尽管有较好的近期疗效,然而肿瘤患者单纯依赖化疗通常难以达到长期生存的目的。本文试图从肿瘤干细胞理论解释抗肿瘤药物近期疗效和远期生存之间存在的矛盾,并探讨抗肿瘤药物的研究发展方向。 相似文献
44.
Silvio ST Tafuri Domenico DM Martinelli Giovanni GC Caputi Annamaria AA Arbore Cinzia CG Germinario Rosa RP Prato 《BMC health services research》2009,9(1):100-5
Background
Mandatory vaccination has contributed to the success of immunisation programmes but voluntary vaccination allows people to be responsible for their own health. There are benefits from both policies and the arguments between them remain subject to debate within and without the scientific community, both nationally and internationally. The aim of this study is to assess the opinions of those who actually work in the Vaccination Service. 相似文献45.
ST Francis S Rawal H Roberts P Riley T Planche NL Kennea 《Acta paediatrica (Oslo, Norway : 1992)》2010,99(11):1691-1694
Objective: Meticillin‐resistant staphylococcus aureus (MRSA) colonization on neonatal units is a common and important clinical problem. Effectiveness of polymerase chain reaction (PCR) for detecting MRSA nasal colonization of infants was evaluated and compared to culture‐based methods. The effect of skin decolonization in affected infants was studied. Methods: Paired nasal swabs were collected from infants in our neonatal unit over a 12‐month period (September 2007–2008). Colonization with MRSA was determined with a commercially available PCR method and compared to culture. Results: A total of 696 paired nasal swabs were taken. Three infants were colonized at the beginning and were included. There were positive PCRs in 12 infants. Five infants cultured MRSA from a nasal swab at the same time. No infants were culture‐positive when PCR was negative (sensitivity 100%, specificity 99% compared to culture). PCR results were available within 24 h. Five infants were PCR+ and isolated meticillin‐sensitive Staphylococcus aureus. This organism gave a false‐positive PCR result. Two infants transferred in on broad‐spectrum antibiotics were PCR+ and negative by culture. Decolonization led to negative nasal PCR and culture in 4/5 infants to discharge. Conclusions: PCR methods are sensitive and specific for detection of MRSA colonization in newborn infants of all gestations with results 1–2 days before culture. 相似文献
46.
47.
ST O'Sullivan MD FRCSI GT McGreal FRCS CM Reardon FRCSI DJ Hehir MCH FRCSI WO Kirwan MCH FRCSI MP Brady MCH FRCSI 《International journal of clinical practice》1997,51(5):289-292
During a four-year period, 308 patients presented following ingestion of foreign bodies. Ingestion was accidental in 272 cases (88.3%) and deliberate in the remainder. Symptoms at presentation included dysphagia, odynophagia, nausea and vomiting, chest pain and pharyngeal discomfort. Sixty-eight patients were asymptomatic. A policy of expectant management and selective endoscopy was employed. Following initial assessment 202 patients (65.6%) were discharged without treatment, 30 (9.7%) of whom were later reviewed as outpatients and did not require admission. Forty-nine patients (16%) were admitted for treatment; 27 had oesophagoscopy, five bronchoscopy and two had foreign body extraction with direct laryngoscopy. In nine patients who were endoscoped, no foreign body was identified. Twenty-seven others were referred to the otorhinolaryngology service in another hospital. There were no deaths in the group and morbidity was 1.2%. We conclude that a policy of selective endoscopy is safe and effective in the management of patients following ingestion of foreign bodies. 相似文献
48.
49.
Paul A ST JOHN 《中国药理学报》2009,(6):656-662
Nicotinic acetylcholine receptors (nAChRs) play critical roles throughout the body. Precise regulation of the cellular loca- tion and availability of nAChRs on neurons and target cells is critical to their proper function. Dynamic, post-translational regulation of nAChRs, particularly control of their movements among the different compartments of cells, is an important aspect of that regulation. A combination of new information and new techniques has the study of nAChR trafficking poised for new breakthroughs. 相似文献
50.
S. K. BRÆKKAN E. B. MATHIESEN I. NJØLSTAD T. WILSGAARD J. STØRMER J. B. HANSEN 《Journal of thrombosis and haemostasis》2008,6(11):1851-1857
Summary. Background: Recent studies indicate that arterial cardiovascular diseases and venous thromboembolism (VTE) share common risk factors. A family history of myocardial infarction (MI) is a strong and independent risk factor for future MI. Objectives: The purpose of the present study was to determine the impact of cardiovascular risk factors, including family history of MI, on the incidence of VTE in a prospective, population‐based study. Patients and methods: Traditional cardiovascular risk factors and family history of MI were registered in 21 330 subjects, aged 25–96 years, enrolled in the Tromsø study in 1994–95. First‐lifetime VTE events during follow‐up were registered up to 1 September 2007. Results: There were 327 VTE events (1.40 per 1000 person‐years), 138 (42%) unprovoked, during a mean of 10.9 years of follow‐up. In age‐ and gender‐adjusted analysis, age [hazard ratio (HR) per decade, 1.97; 95% confidence interval (CI), 1.82–2.12], gender (men vs. women; HR, 1.25; 95% CI, 1.01–1.55), body mass index (BMI; HR per 3 kg m?2, 1.21; 95% CI, 1.13–1.31), and family history of MI (HR, 1.31; 95% CI, 1.04–1.65) were significantly associated with VTE. Family history of MI remained a significant risk factor for total VTE (HR, 1.27; 95% CI, 1.01–1.60) and unprovoked VTE (HR, 1.46; 95% CI, 1.03–2.07) in multivariable analysis. Blood pressure, total cholesterol, HDL‐cholesterol, triglycerides, and smoking were not independently associated with total VTE. Conclusions: Family history of MI is a risk factor for both MI and VTE, and provides further evidence of a link between venous and arterial thrombosis. 相似文献