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91.
Focally endemic bancroftian filariasis is targeted for elimination in the Nile delta of Egypt. Improved methods are needed for identifying endemic villages to be included in the control programme and for monitoring its success. We have evaluated the performance of a polymerase chain reaction (PCR) assay in estimating Wuchereria bancrofti infection in pools of Culex pipiens (1-25 females) from 2 adjacent villages with high (El Qolzom, 10.8%) and low (Kafr Shorafa, 2.1%) prevalence rates of human filariasis. This assay detects a repeated sequence in W. bancrofti deoxyribonucleic acid (DNA). Mosquitoes resting within houses were captured by aspiration and pooled by house. Houses were classified as positive or negative for human filarial infection based on night blood examinations of residents. The assay detected parasite DNA in mosquitoes from 60% of 25 infected houses and 24% of 25 uninfected houses. PCR processing of mosquitoes caught within houses of unknown filariasis infection status (44 in El Qolzom, 37 in Kafr Shorafa) identified 31.8% and 8.1% of houses, respectively, as containing infected mosquitoes. These results support the validity of the PCR assay for evaluating filarial prevalence in different villages. C. pipiens collected outdoors in dry ice-baited traps and tested by PCR (266 in Qolzom, 82 in Kafr Shorafa) did not contain parasite DNA. Pools of female mosquitoes (296 in Qolzom, 240 in Kafr Shorafa) captured in oviposition traps were also negative. We concluded that the PCR based assay is a powerful epidemiological tool that can be used for evaluating W. bancrofti infection in villages in the Nile delta and for monitoring the application of control programmes in filariasis endemic areas.  相似文献   
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93.
Limited studies correlate allergic symptoms and associated outdoor biological particle exposure among schoolchildren globally.This study aimed to investigate the relationship between the seasonality of symptoms of allergic diseases among middle schoolchildren and the annual variation of airborne pollen and fungal spore in a hot and humid geographical region (Qatar).During November 2017 to January 2018, a self-reported study of middle schoolchildren living in the Doha capital city of Qatar was conducted, and data gathered were evaluated in relation to the collected monthly pollen and fungal spores. Participants’ data were collected by conducting a survey based on a modified questionnaire adopted from the International Study of Asthma and Allergy in Childhood (ISAAC). The airborne pollen and fungal spore in Doha''s atmosphere were extracted from the Doha aerobiology project (2017–2020).Among the 1000 distributed questionnaires, 100 were excluded due to significant missing data and 644 middle schoolchildren living in Doha city responded and were included in the final analysis. The symptoms of allergic rhinitis (AR) pattern among the responders with positive symptoms were strongly linked with the higher airborne fungal spore incidence during the month of November. Out of 331 students with positive symptoms, the prevalence of AR, lifetime wheeze, and eczema was 62.8%, 28.1%, and 26.6%, respectively. Asthma was significantly higher in Qatari (39.8%) compared to non-Qatari (26.7%) middle schoolchildren (P = .02).Outdoor aeroallergen may be a contributing factor in addition to other environmental and genetic predisposing factors for childhood atopic diseases in the prevalence rate of allergic symptoms among middle schoolchildren in the peninsula of Qatar.  相似文献   
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95.
There is a growing interest in modulating the temperature under the illumination of light. As a heat source, metal nanoparticles (NPs) have played an important role to pave the way for a new branch of plasmonics, i.e., thermo-plasmonics. While thermo-plasmonics have been well established in photo-thermal therapy, it has received comparatively less attention in materials science and chemistry. Here, we demonstrate the first proof of concept experiment of local chemistry and graphitization of metalized polymeric nanofibers through thermo-plasmonic effect. In particular, by tuning the plasmonic absorption of the nanohybrid through a change in the thickness of the deposited silver film on the fibers, the thermo-plasmonic effect can be adjusted in such a way that high enough temperature is generated enabling local welding and graphitization of the polymeric nanofibers.  相似文献   
96.
Uniform hospital discharge abstract data from Maryland were used to examine the homogeneity of trauma-related DRGs with respect to a well-established measure of injury severity, the Injury Severity Score (ISS). Thirty DRGs were identified as including trauma cases with a wide range of severity; for each of these DRGs, ISS explains a significant amount of variation in length of stay. By applying statistical techniques similar to those used to create the original DRG groupings, these 30 DRGs were subdivided by severity and age categories to create a new set of severity-modified DRGs. The potential effects of using DRGs and modified DRGs to pay for inpatient care within the Maryland state regionalized system of trauma care were examined. Payments based on regional averages per DRG and per modified DRG were compared to actual hospital charges regulated by the state's Health Services Cost Review Commission. Using average charges per DRG as a basis of payment, approximately !1.4 million (11 percent of total hospital charges) would be shifted from trauma centers to nontrauma centers. This shift represents an 18 percent loss in revenues to trauma centers and a 30 percent gain in revenues to nontrauma centers. Using a payment system based on severity-modified DRGs, trauma centers would still experience a net loss in revenues and the nontrauma centers a net gain, but the total amount of the shift would be reduced from $11.4 million to $9.8 million. The results argue for the need to explore alternative payment systems not strictly based on current DRGs. Because of DRGs do not adequately reflect severity differences, using them to pay hospitals will create financial incentives that discourage regionalization of trauma care.  相似文献   
97.
98.
Among 108 primarily psychiatric outpatients surveyed for tardive dyskinesia (TD), eight (7.4%) developed the disorder by the end of a two-year prospective study. A comparison between the TD patients and a control group (matched for age, sex, duration of neuroleptic treatment, and diagnosis) yielded no confirmed predisposing factor differentiating the two populations. However, age, especially in women, may be important in the development of TD.  相似文献   
99.
The incidence of major bowel and diaphragm injuries occurring in association with blunt spleen and liver ruptures in adults was studied. Of 142 patients with splenic injuries, five had major bowel injuries and 12 had diaphragmatic ruptures. Of 102 patients with blunt hepatic injury, 13 had either bowel or diaphragm ruptures or both. Six bowel and diaphragm injuries occurred in 42 patients with blunt ruptures of both the liver and spleen. Anatomically minor spleen injuries were associated with a 4.8% risk of bowel or diaphragm rupture. Anatomically major splenic lacerations had associated bowel or diaphragm wounds in 16.4% of cases (p = 0.024). A 20% incidence of partial-thickness bowel wounds was found in patients with hepatic or splenic injury, but the natural history of these wounds is unknown.  相似文献   
100.
Transbronchial fine-needle aspiration. Reliability and limitations   总被引:3,自引:0,他引:3  
Transbronchial needle aspiration is a new method of sampling pulmonary, paratracheal, and mediastinal masses. A total of 116 aspirations of the lung performed during a two-and-a-half-year period were reviewed. The results were compared with those of bronchial wash, bronchial brush, sputum, transbronchial forceps biopsy, and histologic material subsequently obtained during surgery or at autopsy. Clinical information was also reviewed. Transbronchial needle aspiration was performed on 104 patients, yielding 116 specimens. With the use of a combination of aspiration, wash, brush, sputum, and forceps biopsy, malignancy was detected in 48 patients. Open biopsy, mediastinoscopy, and transcutaneous needle aspiration increased the number of malignant neoplasms detected to 72. The tumors were detected in 67% of these 72 cases by a combination of all bronchoscopic methods. Transbronchial aspiration correctly identified 36% of malignant cases compared with 35% identified by wash, 39% by brush, 25% by sputum, and 59% by forceps biopsy. The overall accuracy of the techniques was 56% for aspiration, 48% for wash, 56% for brush, 35% for sputum, and 71% for forceps biopsy. Malignant cases were associated with cellular transbronchial aspirates, good preservation of cell detail, and a high degree of cytologic/histologic correlation regarding cell type. Transbronchial fine-needle aspiration has the potential for improving the diagnostic ability of bronchoscopy. However, the high incidence of false negative diagnoses is the main limitation for the technique, and the responsible factors are discussed.  相似文献   
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