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11.
Ribotyping as an additional molecular marker for studying Neisseria meningitidis serogroup B epidemic strains. 总被引:2,自引:1,他引:2 下载免费PDF全文
The molecular method of ribotyping was used as an additional epidemiological marker to study the epidemic strains of Neisseria meningitidis serogroup B, referred to as the ET-5 complex, responsible for the epidemic which occurred in greater São Paulo, Brazil. Ribotyping analysis of these strains showed only a single rRNA gene restriction pattern (Rb1), obtained with ClaI restriction enzyme. This method, as well as multilocus enzyme electrophoresis, provided useful information about the clonal characteristics of the N. meningitidis serogroup B strains isolated during this epidemic. The N. meningitidis serogroup B isolates obtained from epidemics which occurred in Norway, Chile, and Cuba also demonstrated the same pattern (Rb1). Ribotyping was a procedure which could be applied to a large number of isolates and was felt to be appropriate for routine use in laboratories, especially because of the convenience of using nonradioactive probes. 相似文献
12.
Development-dependent inheritance of 5-azacytidine-induced epimutations in triticale: analysis of rDNA expression patterns 总被引:3,自引:0,他引:3
Genomic imprinting of rye origin rDNA sequences in triticale is modulated by DNA methylation responsible for ontogenic expression patterns of those sequences. Considering the dynamic nature of these phenomena, we evaluated the influence of plant development on the inheritance of modified rye rDNA expression patterns. DNA hypomethylation was induced in triticale by 5-azacytidine (5AC) treatments at distinct developmental stages of M1 plants, and expression patterns were analysed in M2. The activity of rye origin rRNA genes in progeny of untreated and 5AC-treated plants was evaluated by silver staining in meristematic root tip cells and in meiocytes at diplotene. In the progeny of 5AC-treated plants, a significant increase in rye rDNA expression was observed, contrasting with the residual activity in untreated plants. Significant differential effects of 5AC treatments were observed in M2 plants and correlated with the M1 plant developmental stage in which DNA hypomethylation was induced. Hypotheses to explain the origin of those differences are discussed here.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
13.
Debelenko LV; Brambilla E; Agarwal SK; Swalwell JI; Kester MB; Lubensky IA; Zhuang Z; Guru SC; Manickam P; Olufemi SE; Chandrasekharappa SC; Crabtree JS; Kim YS; Heppner C; Burns AL; Spiegel AM; Marx SJ; Liotta LA; Collins FS; Travis WD; Emmert-Buck MR 《Human molecular genetics》1997,6(13):2285-2290
Lung carcinoids occur sporadically and rarely in association with multiple
endocrine neoplasia type 1 (MEN1). There are no well defined genetic
abnormalities known to occur in these tumors. We studied 11 sporadic lung
carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene
on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy
fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was
studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene
were inactivated. All four tumors showed the presence of a MEN1 gene
mutation and loss of the other allele. Observed mutations included a 1 bp
insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide
substitution affecting a donor splice site. Each mutation predicts
truncation or potentially complete loss of menin. The remaining seven
tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH.
The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a
complex germline MEN1 gene mutation. The data implicate the MEN1 gene in
the pathogenesis of sporadic lung carcinoids, representing the first
defined genetic alteration in these tumors.
相似文献
14.
Santos Marília Neves Azeredo Catarina Machado Rinaldi Ana Elisa Madalena 《Maternal and child health journal》2022,26(7):1496-1506
Maternal and Child Health Journal - The aim of this study was to estimate the association between individual and contextual characteristics related to maternal work and exclusive breastfeeding... 相似文献
15.
Neves Lia Mara Grosso Tim Carla Roberta Floriano Elaine Medeiros da Silva de Avó Lucimar Retto Fernandes João Batista Parizotto Nivaldo Antonio Cominetti Marcia Regina 《Lasers in medical science》2021,36(4):863-870
Lasers in Medical Science - Ultraviolet radiation (UVR) is the major etiologic agent of cutaneous photoaging, and different strategies are used to prevent and treat this condition. The... 相似文献
16.
Mayan O Pires A Neves P Capela F 《Applied occupational and environmental hygiene》1999,14(11):785-790
Shoe manufacturing is a traditional industry in northern Portugal. There are nearly 1500 factories that employ about 54,000 workers. Among the materials used in the shoe manufacturing process, that could be occupational hazards, are the adhesives, especially adhesives solutions based on organic solvents. The National Institute of Health (Oporto Branch) carried out a study of 100 factories in northern Portugal to study solvent exposure in shoe manufacturing. The surveyed population, (4615 workers) was young (mean age = 33 years; range = 18-45) and predominantly female (68.5%). The results from the air samples analyses show 20 different organic compounds existing in the workplaces. The more common compounds found were n-hexane, toluene, and acetone. The results of the study show that in 53.7 percent of the factories there are operations where the solvent exposure is significant and represents a health hazard to the workers. These operations are mainly gluing, waxing, and polishing stations. Occupational risk of exposure to solvents concerned 44.2 percent of the workers. This study points out the existence of inadequate ventilation in the workplaces and inappropriate personal protective equipment to prevent dermatitis risk from adhesives, wax, and polish. The organic solvents present in workplaces also increase fire risk. 相似文献
17.
Porto CM Lazzarini MP Redígolo LR Neves FR 《Revista latino-americana de enfermagem》1999,7(5):121-126
This paper emphasizes the creation and application of a KIT for the communication of occupational accidents with puncture-cutting objects to the Municipal Health Bureau from the city of Ribeir?o Preto. It is an essential instrument for the health care services directed to all the employees of the Health Units. It also evidences the notification and the beginning of the prevention of occupational diseases, being a highly useful instrument whenever any accident occurs. The creation of this KIT enabled the use of prevention measures regarding occupational diseases, culminating with the mobilization of the chiefs and the staff in order to intensify preventive procedures. 相似文献
18.
19.
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
20.
目的总结艾滋病患者在耳鼻咽喉的临床表现.方法10例艾滋病的临床资料回顾性分析.结果10例艾滋病患者,有卡波氏肉瘤8例,颈部肿块8例,皮肤、口腔咽喉黏膜溃疡4例,上呼吸道梗阻行气管切开术2例,单侧慢性化脓性中耳炎者1例.结论艾滋病患者以咽喉、口腔部卡波氏肉瘤及黏膜溃疡出现最早,应引起高度警惕及重视. 相似文献