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51.
Malaria was a major problem in a sericulture area of Karnataka, south India, where Anopheles culicifacies s.l. and A. fluviatilis s.l. were considered to be the main vectors. Sibling species complexes of these two species were analysed in three ecologically different villages. Among A. culicifacies, only sibling species A and B were found. In Puram, a village with 22 wells, species A predominated; species B predominated in a village with four wells and a stream, and in a village with a stream and no wells. Poecilia reticulata fish were introduced into all wells and streams in the villages, and after one year no vectors were found in Puram, and all, or nearly all, A. culicifacies were species B in the other two villages. All A. fluviatilis belonged to the sibling species T. Blood meal analysis indicated that a few of the A. culicifacies collected had fed on humans while all the A. fluviatilis had fed on bovines. Before the introduction of fish, the annual parasite incidence for malaria was high in Puram, but much lower in the other two villages. From 1998 (over one year after release of fish) until 2003, no malaria cases were detected in the three villages.  相似文献   
52.
We have analysed the results of 246 cases of distal femoral tumours treated by resection and prosthetic replacement between 1988 and 2002. Patient ages ranged from 6–67 years averaging 24 years; 133 were males. The most common tumour was osteosarcoma (67% of patients). The follow-up ranged from 2 to 14 years. Stage II tumours were seen in 72% of patients. The technique of sleeve resection of the quadriceps musculature was followed to achieve local clearance of the tumour. The prosthesis used was a rotating hinge custom mega-prosthesis manufactured locally. The functional result achieved was excellent or good in 87%; 86% of the patients had no evidence of disease, and 13% had died. The 10-year patient survival was 76.9%. Periprosthetic fracture and infection were the most common complications.
Résumé Nous avons analysé les résultats de 246 cas de tumeurs fémorales distales traitées par résection et remplacement prothétique entre 1988 et 2002. Lâges des malades sétendait de 6 à 67 ans avec une moyenne de 24 ans. Cent trente trois étaient des hommes. La tumeur la plus fréquente était lostéosarcome (67% des malades). Le suivi était de 2 à 14 années. Des tumeurs de stade II étaient présentes chez 72% des malades. La technique de résection a été conduite pour faire une ablation complète de la tumeur. La prothèse qui a été utilisée était une méga prothèse à charnière rotatoire fabriqué localement. Le résultat fonctionnel obtenu était excellent ou bon dans 87%. Quatre-vingt-six pourcent des malades navait pas dévidence de maladie et 13% étaient morts. La survie à dix ans était de 76,9%. Les fractures périprothétiques et linfection étaient les complications les plus fréquentes.
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53.
Eleven children between 4 and 17 years of age underwent ligation of a patent ductus arteriosus during two medical camps in September 2003 and August 2004 at the Sonam Norboo Memorial District Hospital at Leh, Ladakh (11,400 feet above mean sea level). These children had a low mean arterial oxygen saturation while breathing room air. They were all acclimatized to high altitude. Surgery was performed under general anaesthesia with endotracheal intubation. Patients were extubated on the table. All children survived the operation and were discharged within 5-6 days following surgery. No surgical or anaesthetic complications were encountered. Simple cardiac surgical procedures such as ligation of a patent ductus arteriosus can be performed safely at high altitudes.  相似文献   
54.
OBJECTIVE: The purpose of this study was to assess the long-term results of mitral valve repair in children with chronic rheumatic heart disease. METHODS: From January 1988 through December 2003, 278 children (153 male children) underwent mitral valve repair. Mean age was 11.7 +/- 2.9 years (range, 2-15 years). One hundred seventy-three children (62%) were in the New York Heart Association functional class III or IV. Congestive heart failure was present in 24 (8.6%). Reparative procedures included posterior collar annuloplasty (n = 242), commissurotomy (n = 187), cusp-level chordal shortening (n = 94), cusp thinning (n = 71), cleft suture (n = 65), and cusp excision or plication (n = 10). Associated procedures included atrial septal defect closure (n = 22), aortic valve repair/replacement (n = 13), and tricuspid valve repair (n = 3). RESULTS: Early mortality was 2.2% (6 patients). Preoperative left ventricular dysfunction was associated with greater mortality. Median follow-up was 56.5 months (mean, 58.9. +/- 32.3 months; range, 5 to 180 months). One hundred seventy-seven survivors (65%) had no or trivial mitral regurgitation. Sixteen patients (6%) required reoperation for valve dysfunction. There were 7 late deaths (2.6%). Actuarial, reoperation-free, and event-free survivals at a median follow-up of 56.5 months were 95.2% +/- 1.5%, 91.6% +/- 2.2%, and 55.9% +/- 3.5%, respectively; at 15 years, they were 95.2% +/- 1.5%, 85.9% +/- 5.9%, and 46.7% +/- 4.7%, respectively. CONCLUSION: Mitral valve repair in children with chronic rheumatic heart disease is feasible and provides acceptable long-term results.  相似文献   
55.
Rapid identification of emerging pathogens: coronavirus   总被引:6,自引:0,他引:6  
We describe a new approach for infectious disease surveillance that facilitates rapid identification of known and emerging pathogens. The process uses broad-range polymerase chain reaction (PCR) to amplify nucleic acid targets from large groupings of organisms, electrospray ionization mass spectrometry for accurate mass measurements of PCR products, and base composition signature analysis to identify organisms in a sample. We demonstrate this principle by using 14 isolates of 9 diverse Coronavirus spp., including the severe acute respiratory syndrome-associated coronavirus (SARS-CoV). We show that this method could identify and distinguish between SARS and other known CoV, including the human CoV 229E and OC43, individually and in a mixture of all 3 human viruses. The sensitivity of detection, measured by using titered SARS-CoV spiked into human serum, was approximate, equals1 PFU/mL. This approach, applicable to the surveillance of bacterial, viral, fungal, or protozoal pathogens, is capable of automated analysis of >900 PCR reactions per day.  相似文献   
56.
A robust database shows that dietary supplements of vitamins E and C are safe for the general population. Because these nutrients supply antioxidant and other functions for homeostasis and protection against free radical damage, supplementation has been intensively studied. Because of perceived benefits, many persons consume quantities of vitamins E and C well above the recommended dietary allowances. As safety guidance, tolerable upper intake levels have been established by the Food and Nutrition Board, Institute of Medicine, at 1000 mg for vitamin E and 2000 mg for vitamin C in adults. Many clinical trials with these vitamins have involved subjects with various diseases, and no consistent pattern of adverse effects has occurred at any intake. Numerous studies of vitamin C supplementation have provided no pattern of evidence to support concerns about safety other than occasional gastrointestinal upset or mild diarrhea resulting from the osmotic effects of unabsorbed quantities of vitamin C. Evidence of bleeding effects and other potential adverse effects of high vitamin E intakes in humans is not convincing. Evidence of adverse effects of vitamin C that result from its effects on iron absorption and metabolism has not been confirmed in clinical trials. Thus, we conclude from clinical trial evidence that vitamin E supplements appear safe for most adults in amounts 相似文献   
57.
Sampath G  Parikh S  Sangram P  Briggs DJ 《Vaccine》2005,23(9):1102-1105
Over half of the world's malnourished children live in Asia where more than 90% of reported human rabies deaths occur. In order to determine the effect of malnutrition on the immune response to rabies post-exposure prophylaxis (PEP), 45 children with moderate to severe protein energy malnutrition (PEM) who were exposed to potentially rabid animals were enrolled in a clinical trial. Patients received purified chick embryo cell rabies vaccine (PCECV) on days 0, 3, 7, 14 and 30. Blood was drawn on days 0, 14 and 30 and evaluated for the presence of rabies virus neutralizing antibody. All children that met the protocol criteria developed rabies virus neutralizing antibody titers above the acceptable level of 0.5 IU/mL by day 14 and no serious adverse events were reported. We conclude that children in this study that received four or five doses of rabies vaccine intramuscularly developed an acceptable immune response despite their severe degree of protein energy malnutrition.  相似文献   
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Texture discrimination and bounding contour extraction are essential parts of the object segmentation and shape discrimination process. As such, successful texture and contour processing are key components underlying the development of the perception of both objects and surfaces. By recording visual-evoked potentials, we investigate whether young infants can detect orientation-defined textures and contours. We measured responses to an organized texture comprised of many Gabor patches of the same orientation, alternated with images containing the same number of patches, but all of random orientation. These responses were compared with a control condition consisting of the alternation between two independently random configurations. Significant difference potentials were found as early as 2-5 months, as were significant odd harmonics in the test conditions. Responses were also measured to Gabor patches organized either as circles (all patches tangent to an imaginary circular path) alternated with pinwheels (all patches having a fixed orientation offset from the path). Infants between 6 and 13 months also showed sensitivity to the global organization of the elements along contours. Differential responses to our texture and contour stimuli and their controls could only have been generated by mechanisms that are capable of comparing the relative orientation of 2 or more patches, as no local information at a single patch distinguished the random and organized textures or the circle and pinwheel configurations.  相似文献   
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