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21.
In order to describe the British experience of Wegener's granuiomatosisHospital Activity Analysis was used to collect cases diagnosedin England, Wales and Scotland between 1975 and 1985. Wherepossible clinical details, histological material and chest radiographswere obtained. Two hundred and sixty five patients were consideredto have Wegener's granuiomatosis. In 109 a single pathologistconfirmed the diagnosis by finding both granulomas and vasculitisin biopsy material. The diagnosis was made on clinical groundsor clinical grounds together with histological diagnosis inthe local hospital in 156 patients. Wegener's granuiomatosiswas confined to the lung or upper respiratory tract in 22 percent of patients and renal disease occurred in 58 per cent.Laboratory tests showed a pattern of mild anaemia, polymorphleucocytosis, eosinophilia and an elevated ESR and hypergammaglobulinaemia,with no specific pattern of changes. Histological confirmation was most frequently obtained by examinationof nasal biopsy specimens, but multiple biopsies were oftenrequired. Renal biopsies showed focal proliferative glomerulonephritisbut granulomatous glomerulonephritis was uncommon. Of availablechest radiographs 61 per cent were abnormal, large opacitiesbeing most common. Small irregular opacities were found lessoften and other abnormalities were uncommon. Treatment varied widely and 10 per cent of patients receivedno drug therapy. This large series illustrates that even withoutspecific treatment, patients with Wegener's granuiomatosis cansurvive for several years and with modern treatment survivalfor more than a decade is possible. Conclusions about the effectivenessof the various therapies cannot be drawn from this restrospectivestudy. Renal failure and disseminated vasculities were the commonestcauses of death; death was considered to result from complicationsof treatment with cytotoxic drugs or prednisolone in 6 per centof patients.  相似文献   
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Background  

Hospitalization for heart failure (HF) is associated with high-in-hospital and short- and long-term post discharge mortality. Age and gender are important predictors of mortality in hospitalized HF patients. However, studies assessing short- and long-term risk of death stratified by age and gender are scarce.  相似文献   
24.

Background  

Implementation of medical interventions may vary with organization and available capacity. The influence of this source of variability on the cost-effectiveness can be evaluated by computer simulation following a carefully designed experimental design. We used this approach as part of a national implementation study of ultrasonographic infant screening for developmental dysplasia of the hip (DDH).  相似文献   
25.
The outer supporting cells in the apical turns of the guinea pig cochlea receive a dense innervation. Our previous study (Fechner et al. [1998] J. Comp. Neurol. 400:299-300) suggested that this innervation of the Deiters' and Hensen's supporting cells was not derived from efferent fibers of the olivocochlear bundle, but its origin has not been further specified. To test the hypothesis that the innervation was afferent in origin, we traced apical afferent fibers that were retrogradely labeled by extracellular injections of horseradish peroxidase. Labeled afferent fibers were of two types: type I fibers contacted inner hair cells, whereas type II fibers crossed the tunnel and contacted outer hair cells. Significantly, most of the type II fibers also formed branches to the outer supporting cells. Although a few olivocochlear efferent fibers formed such branches, counts indicated that the overwhelming majority of the branches were produced by type II afferent fibers. These branches were not produced by basal type II fibers. Apical type II fibers also differed from basal fibers by having shorter lengths, spiraling both apically and basally, and contacting all three rows of outer hair cells. These innervation differences suggest differences in the ways that information from outer hair cells is processed in the apex versus the base of the cochlea.  相似文献   
26.
We studied the aetiology of malnutrition in a cohort of 1511 children < 10 years old in Espiritu Santo, Vanuatu. Malnutrition was categorized using standard anthropometric criteria as: underweight [weight-for-age (WA) Z score < -2], wasting [weight-for-height (WH) Z < -2], or stunting [height-for-age (HA) Z < -2]. On multiple logistic regression analysis, the only factors significantly associated with wasting were age < 5 years [OR (95% CI) 1.8 (1.2-2.9), p = 0.01] and having suffered one or more episodes of clinical P. vivax malaria in the 6 months preceding nutritional assessment [OR 2.4 (1.3-4.4), p = 0.006]. The incidence of P. vivax infection was significantly higher during the 6 months preceding assessment in underweight vs. non-underweight children [incidence rate ratio (IRR) 2.6 (1.5-4.4), p < or = 0.0001). These groups had similar incidences of clinical P. falciparum infection during the same period [IRR 1.1 (0.57-2.1) p = 0.8] and of either species during the 6 months following assessment [IRR P. vivax 1.3 (0.9- 2.0) p = 0.2; IRR P. falciparum 1.3 (0.9-1.9) p = 0.2]. In these children, P. vivax malaria was a major predictor of acute malnutrition; P. falciparum was not. Wasting neither predisposed to nor protected against malaria of either species. Although P. vivax malaria is generally regarded as benign, it may produce considerable global mortality through malnutrition.   相似文献   
27.
We determined the prevalence of antibody to cytomegalovirus (CMV) in the sera of non-homosexual hemophilia patients and homosexual men infected with the human immunodeficiency virus type 1 (HIV-1). CMV antibody testing by latex agglutination revealed 33 of 58 HIV-1 infected hemophiliacs (57%) were antibody-positive compared with 54 of 54 HIV-1 infected asymptomatic non-hemophiliac homosexuals (100%) (p less than .001). Nine of 15 hemophiliacs (60%) with symptomatic HIV-1 infection were CMV antibody-positive. We also tested 22 HIV-1 antibody-negative hemophiliacs who had received non-heat treated factor concentrates. 14 of these 22 (64%) were CMV antibody-positive compared with 57% of HIV-1 antibody-positive hemophiliacs. We conclude 1) there is little correlation between transmission of HIV-1 and CMV by factor concentrates, 2) the presence of CMV antibody does not appear to be associated with clinical stage of HIV-1 infection in hemophiliacs, and 3) there may be a significant number of CMV antibody-negative hemophiliacs with HIV-1 infection at risk for primary infection and subsequent disease if CMV seronegative blood products are not provided for future transfusions.  相似文献   
28.
Cardiac abnormalities such as mitral valve prolapse (MVP) are reported to be common features of the Ehlers Danlos syndrome (EDS), and it has been suggested that the majority of patients with type IV EDS will have cardiac involvement and vascular aneurysms. However, the evidence for valve lesions is inconsistent and often based on early clinical studies using mainly M-mode echo. We studied 33 patients (six male, 27 female; median age 35 yr) with EDS (30 type I, II or III, three type IV) and 30 age- and sex-matched controls. The study assessed skin stretch and joint hypermobility using Beighton and Contompasis scores. Echocardiographic examination included standard two-dimensional views from the parasternal and apical windows, and measurement of the aorta at four sites (annulus, sinotubular junction, arch and abdominal aorta). Echocardiographic abnormalities were found in four patients (12.1%) (one atrial septal aneurysm, one tricuspid prolapse, two MVP) and two controls (6.7%). MVP was found in 6.1% of EDS patients and 7% of controls. Seven patients had previously been diagnosed as having MVP; only two were shown to have true MVP using current criteria. None of those with type IV EDS had any echocardiographic abnormality. No patients with EDS had mean aortic dimensions outside the normal range at any of the points tested. Cardiac symptoms were more frequent amongst the patients than controls (atypical chest pain 48%, P = 0.0001; palpitation 39%, P = 0.001; exertional dyspnoea 30%). A wide range of rheumatological complaints were reported (current arthralgia 75%; recent back pain 72%, P = 0.005; recurrent dislocation 72%). Contrary to earlier published observations, we have not found an increased incidence of cardiac abnormalities in EDS. This syndrome may be relatively more benign, from the cardiac point of view, than was previously thought.   相似文献   
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30.
胎儿和新生儿同种免疫性血小板减少症(alloimmune thrombocytopenia,AIT)的发生是由于胎儿的血小板特异性抗原刺激母体产生同种抗体而引起的。胎儿的这种特异性抗原来源于父亲。通常,胎儿和新生儿发生严重AIT绝大多数是由于胎儿-母体PIA1抗原不相容所致,估计这种病例有20%可并发颅内出血。最近,在挪威和苏格兰进行的AIT发生率的前瞻性研究中发现因PIA1所致的新生儿AIT的发病率大约是1%。由于AIT与其他病因引起的新生儿血小板减少症的治疗方法不同,故对AIT的快速诊断将有助于患儿获得最佳治疗。本研究比较了血清学诊断为AIT的新生儿与血清学不支持诊断为  相似文献   
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