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Background and ObjectiveSchool smoking prevention programs have never yielded the expected results. The aim of this study was to analyze the efficacy of an intensive smoking prevention program created by the educational community in which it was to be applied.Population and MethodA 3-year smoking prevention program was carried out among the students of Fuentesaúco Secondary School in Zamora, Spain. The Babilafuente Secondary School in Salamanca, Spain was the control group. The program included both prevention and treatment activities. The former were carried out in the school, in out-of-school situations, and in the community. The questionnaire of the European Smoking Prevention Framework Approach was used.ResultsA total of 417 students aged 12 to 17 years participated in the study. Of these, 54.4% belonged to the intervention group and 45.6% to the control group. Smokers represented 36.7% of the population. After the intervention smokers represented 40.1% of the Fuentesaúco students compared with 46.1% of the Babilafuente students, though the difference was not statistically significant. With respect to the cognitive determinants of smoking behavior, after the intervention significant differences in favor of the intervention group were only observed in the subjects’ perception of the behavior of their siblings, peers, and teachers.ConclusionsThe use of smoking prevention programs in schools should be reconsidered, and their evaluation should be based on educational rather than clinical criteria. Proposed changes in the program include decreasing its intensity, starting with students of an earlier age and seeking greater involvement of parents.  相似文献   
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Germ-line mutations in the BRCA1 gene cause hereditary predisposition to breast and ovarian cancer. BRCA1 and BRCA2 mutations account for about 40% of high-risk families. Mutation-screening methods generally focus on genomic DNA and are usually PCR based; they enable the detection of sequence alterations such as point mutations and small deletions and insertions. However, they do not allow the detection of partial or entire exon(s) loss, because the presence of the homologous allele results in a positive PCR signal, giving rise to a false-negative result. Identification of unusual haplotypes in patient samples by an expectation maximization algorithm has recently been suggested as a method for identifying hemizygous regions caused by large intragenic deletions. Using a similar approach, we identified a novel BRCA1 genomic rearrangement in a breast/ovarian cancer family negative at the first mutation screening; we detected a deletion encompassing exons 14-19, probably due to replication slippage between Alu sequences.  相似文献   
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Roberts syndrome is a rare autosomal recessive condition characterized by growth retardation, cranio-facial abnormalities and symmetrical limb reduction of variable severity. Most patients with Roberts syndrome show a typical cytogenetic finding known as "Roberts syndrome effect". We describe a 4-month-old patient with a mild form of this syndrome, who presented with an asymmetrical reduction of the right upper limb.  相似文献   
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The syndrome of peroneal muscular atrophy, or Charcot-Marie-Tooth (CMT), disease represents the most common inherited peripheral neuropathy, with a prevalence of about 1 per 2500. The disease is usually transmitted in an autosomal dominant fashion, although it can display all the mendelian patterns of inheritance. The chromosome 17-linked form (CMT1a) appears to be the most common form of the disease in all the ethnic groups studied so far, Italians included, and is due to a tandem duplication in 17p11.2. In order to study the distribution of CMT types and to establish a genotype-phenotype correlation in patients from Central and Southern Italy, we collected 19 CMT pedigrees diagnosed in the years 1992–1993. Simple tandem repeats (STR) polymorphism analysis with the marker RM11-GT and Southern blotting with the probes pVAW409R3 and pVAW412 were performed, demonstrating a high prevalence (about 60%) or 17p duplication in the families studied. No clinical or electrophysiological differences were noted between CMT1 patients with or without 17p duplication, respectively. Two families affected by CMT2 showed no evidence of rearrangement at the D17S122 locus. These data are consistent with the hypothesis of a different molecular basis for CMT2.  相似文献   
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Partial trisomy of the long arm of chromosome 10 is a well-defined but rare syndrome. Clinical features of this chromosomopathy are a distinctive dysmorphic appearance, developmental delay, growth retardation, and in some cases, abnormalities of the extremities and renal, cardiac and ocular anomalies. This report describes a neonate with symmetric growth retardation and multiple dysmorphic features, in whom chromosomal analysis revealed a partial trisomy of chromosome 10q with a monosomy of the 13q34 region. The phenotype shares many common features with previously published cases. In addition to the typical features, our case also shows renal hypoplasia with early renal insufficiency and some genital anomalies.  相似文献   
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Condoms act as mechanical barriers to genital infection. In vitro models demonstrate that condoms are almost impermeable to viruses. A small amount of virus may cross the condom, but the condom can still reduce the level of virus exposure by several orders of magnitude. However, in vivo factors, such as condom failure during intercourse, can potentially limit their effectiveness. The weight of available evidence suggests that consistent and correct use of the male condom protects against herpes simplex virus (HSV) infection, as well as other sexually transmitted infections. Female condoms should theoretically protect against HSV infection as they cover a large surface area of potentially infected or susceptible tissues, but research is needed to confirm this. The lack of acceptance, or lack of consistent use, of condoms is the biggest barrier to their effectiveness. There is a need for effective counselling of individuals whose sexual behaviour increases their risk of HSV acquisition, such as young adults. Pregnant women are likely to be receptive to counselling due to the risk of neonatal herpes. No commercially available microbicides specifically inhibit HSV, although many inactivate the virus. More potent and specific microbicides are in development, but may be more expensive than those currently available. Although the effectiveness of condom and microbicide use is not completely proven, there is sufficient evidence to support the promotion of their use by healthcare professionals as an important part of safe sex counselling.  相似文献   
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Review of the mutagenicity of ethylene oxide   总被引:4,自引:0,他引:4  
Ethylene oxide has been shown to be an effective mutagen in a variety of organisms ranging from bacteria to mammalian cells. There is also an association between ethylene oxide exposure and human somatic cell cytogenetic damage. Furthermore, ethylene oxide has been shown to alkylate protein and DNA at exposure levels that have been encountered occupationally. Ethylene oxide is not only effective at producing somatic cell mutations but also at inducing genetic damage in germ cells. While it is clear that ethylene oxide is a germ cell mutagen in whole mammals, the mechanism(s) by which it produces genetic lesions in germ cells is uncertain.  相似文献   
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