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41.
We studied the epidemiology of cholera in Katanga and Eastern Kasai, in the Democratic Republic of Congo, by compiling a database including all cases recorded from 2000 through 2005. Results show that lakes were the sources of outbreaks and demonstrate the inadequacy of the strategy used to combat cholera.  相似文献   
42.
The aim of the present study was to clinically evaluate fissure sealants on the occlusal fissures and buccal pits of permanent first and second molars after 20 and 15 years, respectively. The population consisted of 72 children, each of whom had had their four first molars sealed between 1977 and 1980. At the annual examinations, all caries-free, newly erupted second molars were sealed. When sealant was applied to the second molars, the first molars were checked and sealant was reapplied to those that had deficient sealants. At the follow-up, when the subjects were 26–27 years of age, 27 in the original group had moved from the community. Thus, the present result is based on 45 subjects. One hundred and fifty-three sealed first molars and 161 sealed second molars were available for inspection. At the follow-up examination of the first molars 20 years after sealant had been applied, 65% showed complete retention, 22% partial retention without caries, and 1306 caries or restoration in the occlusal fissures or buccal pits. At the 15-year follow-up of the second molars, the corresponding figures were 65%, 30% and 5%, respectively. Of the restored or carious molars, significantly more were found in the mandible than in the maxilla ( P  < 0.001). This longitudinal study showed that pit and fissure sealants, applied during childhood, have a long-lasting, caries-preventive effect.  相似文献   
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用化学偶联法将抗人膀胱癌单克隆抗体分子偶联到阿霉素白蛋白毫微球上,构建了一个有靶向杀伤性的免疫毫微球,即:阿霉素白蛋白载单克隆抗体毫微球(ADR-NP-Ab)。改变阿霉素毫微球和单克隆抗体的反应分子比,确定了制备该免疫毫微球的最佳条件。经免疫荧光检测及显微照像分析证明,免疫毫微球可有效地和人膀胱癌细胞结合。体外杀伤试验表明,此免疫毫微球对靶细胞EJ有高度特异杀伤活性,而对无关的人直肠癌Lovo细胞则无明显作用。  相似文献   
45.
BACKGROUND: The human Fc gamma receptor IIa (Fc gamma RIIa) is expressed in two polymorphic forms, Fc gamma RIIa-H131 and Fc gamma RIIa-R131, that differ by the replacement of histidine by arginine at position 131. This replacement is caused by a single-nucleotide exchange of A–>G. The resulting receptor forms differ in their binding to human IgG2 and mouse IgG1, which may lead to a different immunologic defense to bacterial polysaccharides and encapsulated bacteria. STUDY DESIGN AND METHODS: A rapid and easy polymerase chain reaction(PCR) method of genotyping the Fc gamma RIIa was developed. Allele-specific primers discriminate between the Fc gamma RIIa-H131 and the Fc gamma RIIa-R131 forms of the receptor. The results were compared with those obtained by another DNA-based genotyping method, in which PCR-amplified DNA was hybridized with allele-specific oligonucleotides, and with a functional phagocytosis assay using mouse IgG1-coated red cells as target antigens. RESULTS: The genotypes deduced from the PCR with allele-specific primers were in complete accordance with those obtained by the data from the hybridization of PCR-amplified DNA with allele- specific oligonucleotides. Furthermore, the Fc gamma RIIa genotypes of 28 individuals in all cases corresponded to the functional phenotypes. CONCLUSION: The use of PCR with allele-specific primers provides a rapid and easily performed method for the determination the Fc gamma RIIa polymorphism.  相似文献   
46.
Introduction of iodinated contrast into the intact colon is not expected to result in imaging‐visible renal excretion of this contrast and is a phenomenon that has only rarely been described. We present a case in which such vicarious renal excretion was misinterpreted as a recto‐vesical fistula which resulted in unnecessary delay in the patient’s management.  相似文献   
47.
To precisely determine the genotype of Epstein-Barr virus (EBV) in Hodgkin's disease (HD), we simultaneously analyzed three divergent gene loci (EBNA-2, EBNA-3C, and EBER) that distinguish type A and B viruses. The primers designed to amplify these three gene loci encompass either type-specific deletion sequences (EBNA-2 and EBNA-3C) or type-specific point mutations (EBER) that identify the virus strain based on the sizes of the polymerase chain reaction (PCR)-amplified products or the mobility shifts in single-strand conformation polymorphism analysis. The locations of point mutations were identified by direct sequencing of the PCR-amplified DNA. We analyzed 15 EBV-infected cell lines and found a good correlation between EBNA-2 and EBNA-3C typing results. In contrast, approximately 33% of the cell lines analyzed maintained type A sequences in EBNA-2 and EBNA-3C genes while carrying type B sequences in the EBER region. Data obtained from analysis of cell lines served as a reference for studying HD samples. EBV DNA was detected in about 70% of HD. Among the EBV-positive samples, 56% were associated with type A virus, 13% with type B, and 31% with dual viral sequences. Thus, type A virus is predominant in HD. Based on the histology, the frequencies of EBV positivity were 83%, 71%, and 33% for mixed cellularity, nodular sclerosis, and lymphocyte predominance, respectively. The detection of high frequency of both type A and B sequences in HD may provide a lead in investigating the role of dual viral infection in EBV pathogenesis.  相似文献   
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49.
Monkeypox (MPX) is a zoonotic Orthopoxvirus infection endemic in central and western Africa. Human MPX cases occur in the central and northern regions of the Democratic Republic of the Congo (DRC), and this is the first report of confirmed MPX cases in the forested areas of North and South Kivu Provinces, with a detailed epidemiological investigation for one case. The location of each case is within areas predicted to be suitable for MPX virus transmission based on an ecological niche model. Phylogenetic analysis places these viruses in the Congo Basin clade.  相似文献   
50.
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