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81.

Background  

A supervised land cover classification was developed from very high resolution IKONOS satellite data and extensive ground truth sampling of a ca. 10 sq km malaria-endemic lowland in western Kenya. The classification was then applied to an investigation of distribution of larval Anopheles habitats. The hypothesis was that the distribution and abundance of aquatic habitats of larvae of various species of mosquitoes in the genus Anopheles is associated with identifiable landscape features.  相似文献   
82.
首次测定确立高催乳血症必需避免过度的静脉穿刺压力,理想的情况是醒后或饭后致少1h来测试.  相似文献   
83.

Background  

Primary care reform initiatives in Ontario are proceeding with little information about the views of practicing family physicians.  相似文献   
84.
背景:血管运动性肾病是早产儿常见的肾功能障碍性疾患。目的:确定茶碱是否可以预防有呼吸窘迫综合征的极早产儿罹患血管运动性肾病。方法:随机双盲安慰剂对照试验,50例胎龄≤32周须辅助通气的早产儿。婴儿接受3d茶碱(1m g/kg)或安慰剂静脉注射。每天测定其24h尿量。在第2、第5及第11天,收集血样及12h尿并进行电解质、肌酐、尿素分析。结果:茶碱组患儿的第1天排尿量的组别x(s)为2.4(0.9)m l/(kg·h),显著高于安慰剂组[1.6(1.0)m l/(kg·h);P=0.023]。茶碱组少尿或无尿的发生率(5%)显著低于安慰剂组(33%)。在第一次给予茶碱/安慰剂后24h,茶碱…  相似文献   
85.
Parvovirus: the expanding spectrum of disease   总被引:6,自引:0,他引:6  
Treatment of parvovirus infections among immunocompromised hosts using immunoglobulin has provided the clinician with a useful therapeutic tool but has also highlighted the problems concerning chronic disease states. The discovery of the human parvovirus B19 in 1975 and subsequent studies of its effects in humans have identified this virus as the causative agent of a broad spectrum of diseases. Recent improvements regarding the development of sensitive PCR techniques and methods for cultivation have provided new insight into its pathogenic role, its virology and immunology, and the varied clinical manifestations. The current state of knowledge concerning parvovirus enabled us to divide the long list of diseases caused by this virus into three main categories: (1) diseases found among normal hosts (asymptomatic disease, erythema infectiosum, arthropathy, hydrops fetalis), (2) hematologic diseases (aplastic crisis, chronic anemia, idiopathic thrombocytopenic purpura, transient erythroblastopenia of childhood, Diamond-Blackfan anemia) and, finally, (3) a heterogeneous group of diseases, in which the etiologic role of parvovirus is less clear and sometimes putative (neurologic disease, rheumatologic disease, vasculitic and myocarditic syndromes). In particular, arthropathy, hydrops fetalis and the hematologic disorders may be of pediatric concern. Consequently, it is of paramount importance that in all of these cases the clinician includes parvovirus as a differential diagnosis.  相似文献   
86.
BACKGROUND: This study documents (1) the progression of atherosclerosis along the entire arterial tree in APOE*3-Leiden mice after 1, 4, 6, 9, and 12 months of a high-fat/high-cholesterol (HFC) diet and (2) the amount and phenotype of DNA-synthesizing and apoptotic cells in different lesion types after 6 months of HFC diet. METHODS AND RESULTS: Diet duration was correlated with a craniocaudal progression of lesion development and with an increase in severity of the lesion. Typically, the lesions contained smooth muscle cells, macrophages, and T lymphocytes and were covered by an intact endothelium. Whereas DNA synthesis (BrdU uptake) was usually elevated in type II lesions (8.6+/-0.8% versus 1.0+/-0.2% in the nondiseased arterial wall; P<0.05), apoptosis was found primarily in advanced lesions (type IV, 1.3+/-0.1% and type V, 1.2+/-0.2% versus 0.04+/-0.04% in the nondiseased arterial wall [P<0.05]). Cell phenotyping revealed that the majority of DNA synthesis and apoptosis was confined to the macrophage-derived foam cell (68.6+/-3. 0% and 82.2+/-4.6%, respectively). CONCLUSIONS: This study shows that in APOE*3-Leiden mice, duration of an HFC diet is associated with (1) a craniocaudal progression of lesion development and (2) an increased complexity of atherosclerotic lesions. Furthermore, DNA synthesis is predominant in early lesions, whereas apoptosis is present mainly in more advanced lesions. Both parameters of cell turnover are confined primarily to the macrophage-derived foam cell.  相似文献   
87.
Transient programmed upper limit stimulation (150 bpm) was observed during repetitively utilized electrocautery in the beginning of an open-heart surgical procedure in a patient with a minute ventilation rate responsive ventricular pacemaker. This tachycardia caused severe hemodynamic deterioration, and was also initiated by internal heart massage and manual ventilation. Considering the recommendations of the manufacturer, this series of serious events could have been prevented, when reprogramming to the inhibited mode had been executed in anticipation of the operation.  相似文献   
88.
BACKGROUND AND OBJECTIVES: An increased prevalence of rheumatoid arthritis (RA) has been reported in several American Indian and Alaska Native (AI/AN) populations. This article reviews the prevalence of RA in these populations, including clinical and serologic features. METHODS: References were taken from Medline through November 2003, in addition to the Arctic Health Literature Database and the American Indian and Alaska Native Health Bibliography. RESULTS: Published articles reveal an increased prevalence of RA in the Tlingit, Yakima, Pima, and Chippewa Indians. Clinically the disease in these groups is often severe, with early age of onset, high frequency of radiographic erosions, rheumatoid nodules, and positive rheumatoid factor. Studies of HLA alleles in cases and controls have found a high frequency of HLA DRB1*1402. CONCLUSIONS: The increased prevalence of RA and more severe disease in specific AI/AN populations suggest an important genetic influence on the development of RA in AI/AN populations. A high frequency of specific high-risk HLA alleles in these populations may account for some of the increased risk, but other genetic factors are likely to contribute. Environmental factors have not been studied in detail, but may also play an important role. RELEVANCE: Understanding the patterns and burden of disease in AI/AN populations may contribute to understanding the etiology of RA and to the development of preventive strategies.  相似文献   
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