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51.
Cancré N Tall A Rogier C Faye J Sarr O Trape JF Spiegel A Bois F 《American journal of epidemiology》2000,152(8):760-770
Plasmodium falciparum has a complex transmission cycle. Public health planning and research would benefit from the ability of a calibrated model to predict the epidemiologic characteristics of populations living in areas of malaria endemicity. This paper describes the application of Bayesian calibration to a malaria transmission model using longitudinal data gathered from 176 subjects in Ndiop, Senegal, from July 1, 1993, to July 31, 1994. The model was able to adequately predict P. falciparum parasitemia prevalence in the study population. Further insight into the dynamics of malaria in Ndiop was provided. During the dry season, the estimated fraction of nonimmune subjects goes down to 20% and then increases up to 80%. The model-predicted time-weighted average incidences contributed by nonimmune and immune individuals are 0.52 cases per day and 0.47 cases per day, respectively. The median times needed to acquire infection (conversion delay) for nonimmune and immune individuals are estimated at 39 days and 285 days, respectively. 相似文献
52.
CONTEXT: Since the beginning of the North Atlantic Treaty Organization intervention in Kosovo in June 1999, few objective data have been available on relevant health indicators for the Serbian ethnic minority in Kosovo. OBJECTIVE: To determine the prevalence of undernutrition among Serbian adults aged 60 years or older and psychiatric morbidity among the adult Serbian population in Kosovo. DESIGN, SETTING, AND PARTICIPANTS: A systematic random sample survey of 212 households was conducted between September 27 and October 2, 1999, in Pristina, the capital city, and in 10 towns in the rural municipality of Gnjilane in Kosovo. Of the 212 households surveyed, 204 adults aged 15 years or older completed the General Health Questionnaire-28 (GHQ-28) and anthropometric measurements were taken for 98 adults aged 60 years or older and for a comparison group of 51 adults aged 18 to 59 years. MAIN OUTCOME MEASURES: Body mass index of less than 18.5 kg/m(2) in older adults; nonspecific psychiatric morbidity among adults; and self-reported use of health care services, access to food rations, and primary sources of prewar and postwar income. RESULTS: Undernutrition was found in 11.2% (95% confidence interval [CI], 5.7%-19.2%) of Serbian adults aged 60 years or older compared with 2.0% (95% CI, 0.1%-11.8%) of Serbian adults aged 18 to 59 years. The mean (SE) total score for the GHQ-28 was 13.0 (0.52). In a comparison of the GHQ-28 scores of the Serbian adults with the Kosovar Albanian adults (data from a recent survey), the mean (SE) score adjusted for age and sex was 12.8 (0.52) vs 11.1 (0.58); P =.03, respectively. The GHQ-28 scores were also higher for the Serbians in the subcategories of social dysfunction (2.8 [0.17] vs 2.2 [0.13]; P =.008) and severe depression (1.9 [0.15] vs 0.9 [0. 09]; P<.001), respectively. Serbian women and persons living alone or in small family units were more prone to psychiatric morbidity. Of the 141 respondents reporting the need for health care services, 83 (57.6%) reported not obtaining such services; 204 of 212 (96.2%) households were on a food distribution list. The majority of prewar income came from government jobs compared with farming and humanitarian aid for postwar income. CONCLUSIONS: The undernutrition of older Serbian adults in Kosovo should be monitored. The high prevalence of symptoms of social dysfunction and severe depression suggest the need for implementation of mental health programs in the Serbian community. JAMA. 2000;284:578-584 相似文献
53.
Wang WS; Hsieh RK; Chiou TJ; Liu JH; Fan FS; Yen CC; Tung SL; Chen PM 《Japanese journal of clinical oncology》1998,28(9):551-554
A 54-year-old man was treated with weekly 24-h infusion of high-dose
5-fluorouracil (2600 mg/m2) and leucovorin (100 mg/m2) for metastatic colon
cancer. At first, he tolerated the treatment well and no significant
toxicity was identified. After a total of eight courses of treatment, a
stable disease was observed, but mild shortness of breath was found on
occasion. The patient had no previous history of cardiac disease and the
heart performance assessed by left ventricular ejection fraction before
treatment was normal. Unfortunately, acute pulmonary edema with lethal
cardiogenic shock occurred during the ninth course of treatment, in spite
of intensive medical treatment. The chest X-ray showed extreme
cardiomegaly. Repeated assessment of his heart function by echocardiogram
and ventricular ejection fraction revealed a very poor cardiac performance.
Toxic cardiogenic shock during weekly 24-h infusion of high-dose
5-fluorouracil and leucovorin is extremely rare. To the best of our
knowledge, no case has been reported in the English literature. We report a
case and the relevant literature about the incidence, clinical picture and
possible pathophysiology on 5-fluorouracil-related cardioxicity is
reviewed.
相似文献
54.
BACKGROUND: Currently, quantitative measurement of global cerebral blood flow (CBF) at bedside is not widely performed. The aim of the present study was to evaluate a newly developed method for bedside measurement of CBF based on thermodilution in a clinical setting. METHODS: The investigation was performed in 14 anesthetized patients before coronary bypass surgery. CBF was altered by hypocapnia, normocapnia, and hypercapnia. CBF was measured simultaneously by the Kety-Schmidt inert-gas technique with argon and a newly developed transcerebral double-indicator dilution technique (TCID). For TCID, bolus injections of ice-cold indocyanine green were performed via a central venous line, and the resulting thermo-dye dilution curves were recorded simultaneously in the aorta and the jugular bulb using combined fiberoptic thermistor catheters. CBF was calculated from the mean transit times of the indicators through the brain. RESULTS: Both methods of measurement of CBF indicate a decrease during hypocapnia and an increase during hypercapnia, whereas cerebral metabolic rate remained unchanged. Bias between CBF(TCID) and CBFargon was -7.1+/-2.2 (SEM) ml x min(-1) x 100 g(-1); precision (+/- 2 x SD of differences) between methods was 26.6 ml x min(-1) x 100 g(-1). CONCLUSIONS: In the clinical setting, TCID was feasible and less time-consuming than alternative methods. The authors conclude that TCID is an alternative method to measure global CBF at bedside and offers a new opportunity to monitor cerebral perfusion of patients. 相似文献
55.
Spiegel DA Ganley TJ Akbarnia H Drummond DS 《Clinical orthopaedics and related research》2000,(381):137-144
A review of clinical records and radiographs revealed that five of 10 patients with conjoined twinning (three of six ischiopagus and two of two pyopagus twins) had congenital vertebral anomalies including hemivertebrae (3), multiple thoracic anomalies (1), right hemisacral agenesis (1), and three lumbar vertebra (1). No mirror image anomalies were identified, and different regions of the spine were involved in the two cases in which both twins had anomalies. Coexisting visceral and musculoskeletal anomalies included dextrocardia (3), atrial septal defect (1), congenital vertical talus (2), Sprengel's deformity (1), and multiple unilateral foot anomalies (1). Hip subluxation or dislocation was seen in five of eight ischiopagus or pyopagus twins after separation and required femoral and pelvic osteotomies. Lumbar scoliosis not associated with congenital vertebral anomalies was seen in two ischiopagus twins. These observations suggest an association between ischiopagus and pyopagus conjoined twins and congenital vertebral anomalies, and their coexistence is explained best by a nonspecific teratogenic insult during early embryogenesis. 相似文献
56.
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59.
Christoph Hartmann Lucas van den Bosch Johannes Spiegel Dominik Rumschttel Daniel Günther 《Materials》2022,15(11)
Binder jetting is a layer-based additive manufacturing process for three-dimensional parts in which a print head selectively deposits binder onto a thin layer of powder. After the deposition of the binder, a new layer of powder is applied. This process repeats to create three-dimensional parts. The binder jetting principle can be adapted to many different materials. Its advantages are the high productivity and the high degree of freedom of design without the need for support structures. In this work, the combination of binder jetting and casting is utilized to fabricate metal parts. However, the achieved properties of binder jetting parts limit the potential of this technology, specifically regarding surface quality. The most apparent surface phenomenon is the so-called stair-step effect. It is considered an inherent feature of the process and only treatable by post-processing. This paper presents a method to remove the stair-step effect entirely in a binder jetting process. The result is achieved by controlling the binder saturation of the individual voxel volumes by either over or underfilling them. The saturation is controlled by droplet size variation as well as dithering, creating a controlled migration of the binder between powder particles. This work applies the approach to silica sand particle material with an organic binder for casting molds and cores. The results prove the effectiveness of this approach and outline a field of research not identified previously. 相似文献
60.