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51.
The epidemiology of tuberculosis among asylum seekers in The Netherlands: implications for screening. 总被引:1,自引:0,他引:1
J L van Burg S Verver M W Borgdorff 《The international journal of tuberculosis and lung disease》2003,7(2):139-144
OBJECTIVE: To identify low-risk groups among asylum seekers in the Netherlands that may be excluded from tuberculosis (TB) screening at entry or during follow-up. METHODS: A retrospective cohort study of medical records of asylum seekers entering the country between January 1994 and March 1997. RESULTS: Medical records were available for 46,424 of the 96,000 asylum seekers (48%) in this period. One hundred and three pulmonary TB cases were diagnosed at entry (prevalence 222/100,000). Risk factors were age >11 years, history of imprisonment and country of origin at war or with TB incidence >100/100,000. During a mean follow-up period of 10 months, 51 pulmonary TB cases were diagnosed (incidence 134/100,000 person-years). Risk factors were age >11 years, old lesions on entry X-ray, and country of origin whose asylum seekers had a prevalence of TB at entry >200/100,000. CONCLUSIONS: We conclude that 1) those with abnormal X-ray at entry should receive preventive therapy after exclusion of active TB, or undergo intensive follow-up, 2) periodic screening is not indicated for immigrants from countries whose asylum seekers have a low prevalence of pulmonary TB at entry, and 3) children <12 years can be excluded from screening. 相似文献
52.
Spinal malignancies are an essential consideration when a patient presents to a chiropractic office with back pain. This single case report exemplifies the importance of patient presentation and physical examination findings. We must also consider the rationale for x-raying patients on an individual case basis. Textbook cases do not always exist and special diagnostic tests do not always provide a definitive diagnosis of underlying pathology. Even though history and examination findings suggest a routine diagnosis, continual re-evaluation and recognition of the need to change the diagnosis on occasion is extremely important. The patient should not only be thoroughly evaluated upon initial presentation, but also each time they present for treatment. The decision to x-ray a patient is considered important. X-ray examination can be used to confirm a diagnosis or to rule out potential pathologies, and not necessarily done as a routine screening procedure.A case report is presented in which the pathologic signs were not evident on plain film x-rays upon initial presentation. 相似文献
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55.
High prevalence of tuberculosis in previously treated patients, Cape Town, South Africa 总被引:1,自引:0,他引:1
den Boon S van Lill SW Borgdorff MW Enarson DA Verver S Bateman ED Irusen E Lombard CJ White NW de Villiers C Beyers N 《Emerging infectious diseases》2007,13(8):1189-1194
The tuberculosis (TB) notification rate is high and increasing in 2 communities in Cape Town, South Africa. In 2002, we conducted a prevalence survey among adults > or = 15 years of age to determine the TB prevalence rate; 15% of households in these communities were randomly sampled. All persons living in sampled households were eligible for chest radiography and sputum examination. Of the 3,483 adults who completed a questionnaire, 2,608 underwent chest radiography and sputum examination. We detected 26 bacteriologically confirmed TB cases and a prevalence of 10.0/1,000 (95% confidence interval [CI] 6.2-13.8 per 1,000). We found 18 patients with smear-positive TB, of whom 8 were new patients (3.1/1,000, 95% CI 0.9-5.1/1,000). More than half of patients with smear-positive TB (10, 56%) had previously been treated. Such patients may contribute to transmission of Mycobacterium tuberculosis and the high TB prevalence rate. Successful treatment of TB patients must be a priority. 相似文献
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Zaman K Hossain S Banu S Quaiyum MA Barua PC Salim MA Begum V Islam MA Ahmed J Rifat M Cooreman E Van Der Werf MJ Borgdorff M Van Leth F 《Epidemiology and infection》2012,140(6):1018-1027
The aim of this study was to determine the nationwide prevalence of smear-positive tuberculosis (TB) in Bangladesh. A multi-stage cluster survey of a random sample of persons aged ≥ 15 years was included in 40 clusters (20 urban, 20 rural). Two sputum samples were collected from study participants and tested initially by fluorescence microscopy and confirmed by the Ziehl-Neelsen method. The crude and adjusted prevalence rates and 95% confidence intervals (CIs) were calculated using standard methods. A total of 33 new smear-positive TB cases were detected among 52 098 individuals who participated in the study. The average participation rate was over 80%. The overall crude prevalence of new smear-positive TB in persons aged ≥ 15 years was estimated as 63.3/100 000 (95% CI 43.6-88.9) and the adjusted prevalence was 79.4/100 000 (95% CI 47.1-133.8). TB prevalence was higher in males (n = 24) and in rural areas (n = 20). The prevalence was highest in the 55-64 years age group (201/100 000) and lowest in 15-24 years age group (43.0/100 000). The prevalence was higher in persons with no education (138.6/100 000, 95% CI 78.4-245.0). The overall prevalence of smear-positive TB was significantly lower than the prevalence estimate of the previous nationwide survey in Bangladesh in 1987-1988 (870/100 000). 相似文献
59.
On the interaction of rabbit antithrombin III with the luminal surface of the normal and deendothelialized rabbit thoracic aorta in vitro 总被引:2,自引:0,他引:2
Pure rabbit antithrombin III was isotope labeled (with 125I or 3H) by two different methods; neither procedure caused a loss of antithrombin activity although both methods affected the affinity of the protein for Sepharose-heparin. From segments from freshly excised rabbit aorta, the uptake of isotope-labeled antithrombin III by the endothelium was rapid and saturable, although relatively small compared to the uptake of thrombin; binding of 3H-antithrombin III to the endothelium resembled that of 125I-antithrombin III. Transendothelial passage of antithrombin III into the subendothelial layers (intima-media) was slow and progressive. Endothelium binding was not affected by pretreating the vessel with either heparin, thrombin, or glycosaminoglycan-specific enzymes. Endothelium-bound antithrombin III was not selectively displaced by either heparin or thrombin. In contrast, endothelium-bound thrombin was rapidly dislodged by antithrombin III as a thrombin- antithrombin III complex. The surface of the deendothelialized aorta (ie, subjected to a balloon catheter) bound antithrombin III avidly. Pretreatment of the deendothelialized vessel with glycosaminoglycan- specific enzymes, particularly heparitinase, decreased intima-media binding by up to 80%. 125I-antithrombin III, when bound to the deendothelialized vessel surface, was actively displaced by either heparin, thrombin, or by unlabeled antithrombin III. The relatively poor binding of antithrombin III compared with that of thrombin by the endothelium in vitro supports an earlier proposal (Lollar P, Owen WG: J Clin Invest 66:1222-1230, 1980) that thrombin bound to high-affinity sites, possibly pericellular proteoglycan, of the endothelium is inactivated by plasma antithrombin III in vivo. Such a situation probably holds for large arteries at least. 相似文献
60.
Conditions were developed in which 80% to 90% of platelet fibrinogen could be routinely purified in nondegraded form from the fluid phase of platelet suspensions stimulated with the calcium ionophore, A23187, in the presence of calcium, leupeptin, and prostaglandin E1. Fibrinogen was separated from other released proteins by chromatography on diethylaminoethanol (DEAE)-cellulose using a continuous pH and ionic strength gradient. Purified platelet fibrinogen, greater than 98% homogeneous by immunoelectrophoresis and sodium-dodecyl sulfate- polyacrylamide gel electrophoresis (SDS-PAGE), consisted of intact A alpha, B beta and gamma A chains, but not gamma' chains, and was 95% to 96% clottable. Platelet fibrinogen was shown to compete for the binding of radiolabeled plasma fibrinogen to ADP-activated platelets in a manner identical to that of unlabeled plasma fibrinogen itself. Also, at equivalent protein concentrations, platelet and plasma fibrinogens supported platelet aggregation to an equivalent extent. Based upon these results, we conclude that there is no significant difference between platelet and plasma fibrinogen with respect to their size, their clottability, their affinity for the activated platelet fibrinogen receptor, or their capacity to support subsequent platelet aggregation. 相似文献