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BACKGROUND: Tobacco smoking is the principal cause of lung cancer. The risk of lung cancer in the offspring of lung cancer patients is about twice higher than the risk in the general population. The present study investigated the contribution of shared smoking habits to the familial clustering of lung cancer. METHODS: We estimated the relative risk of lung cancer attributable to smoking according to the extent to which smokers transmit their smoking habits to the offspring (heritability of smoking), the prevalence of smoking in the general population, and the risk of lung cancer for smokers compared with nonsmokers. FINDINGS: The relative risk of lung cancer for the offspring of lung cancer patients attributable to smoking was 1.19 when published data on smoking practice were modeled (i.e., assuming that the heritability of smoking was 0.5, the smoking prevalence 40%, and the odds ratio of lung cancer for smokers versus nonsmokers was 20). INTERPRETATION: Most familial cases of lung cancer cannot be attributed to shared smoking habits. The example of smoking can be used for other familial cancers, for which no strong environmental risk factors are usually known, to infer the primary role for heritable genes.  相似文献   
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The importance of genetic factors in the etiology of non-Hodgkin lymphoma (NHL) is suggested by case-control and cohort studies. Most previous studies have been too small to estimate accurately risks of specific categories of lymphoproliferative malignancies in relatives of NHL cases or to quantify the contribution of NHL case characteristics to familial risk. We have overcome sample size limitations and potential recall bias by using large databases from Sweden and Denmark. Diagnoses of lymphoproliferative malignancies were compared in 70,006 first-degree relatives of 26,089 NHL cases (including 7,432 with subtype information) versus 161,352 first-degree relatives of 58,960 matched controls. Relatives of NHL cases were at significantly increased risk for NHL [relative risk (RR), 1.73; 95% confidence interval (95% CI), 1.39-2.15], Hodgkin lymphoma (RR, 1.41; 95% CI, 1.0-1.97), and nonsignificantly for chronic lymphocytic leukemia (CLL; RR, 1.31; 95% CI, 0.93-1.85). No increased risk was found for multiple myeloma among case relatives. Findings with respect to siblings compared with parents and offspring or with respect to age at diagnosis of proband were inconsistent. In both populations, relatives of cases with an aggressive NHL subtype were at substantially increased risk of NHL (combined RR, 3.56; 95% CI, 1.80-7.02). We conclude that NHL has an important familial component, which is shared with Hodgkin lymphoma and CLL. We estimate that the absolute lifetime risk for a first-degree relative of an NHL case to develop NHL is 3.6% (compared with a population risk of 2.1%) and higher if the index case had an aggressive subtype of NHL.  相似文献   
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This study evaluates the suitability of Xpert HPV (Cepheid, Sunnyvale, CA, USA) test for cervical and tonsillar formalin‐fixed paraffin‐embedded (FFPE) tissue samples as compared to the tests currently used in diagnostics. Cervical biopsies and liquid cytology (LC) samples were collected from 48 women attending colposcopy. Biopsies were processed for histology and tested for hrHPV using Xpert HPV. LC samples were tested using Xpert and Hybrid Capture 2 (HC2; Qiagen, Hilden, Germany) tests. Also 29 archived tonsillar carcinoma samples were tested using Xpert, and the results were compared with histology and immunohistochemical p16INK4a (p16) staining. Among valid cervical LC samples 46.8% were hrHPV positive using Xpert test and 55.3% with HC2. The sensitivity of Xpert was 84.6% as compared to HC2, and overall test concordance was 91.5%. Test concordance between valid Xpert results from biopsies and LC samples was 84.6%. Among valid tonsillar samples 70.4% were hrHPV positive, and concordance of 96.3% was found between Xpert and p16 staining. To conclude, Xpert HPV test cartridge provides a convenient platform to test individual samples, including FFPE samples. Further studies are needed to establish whether test sensitivity is sufficient to reliably differentiate between hrHPV positive and hrHPV negative head and neck carcinomas.  相似文献   
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An in vitro degradation study of three bioresorbable glass fiber-reinforced poly(l-lactide-co-dl-lactide) (PLDLA) composites was carried out in simulated body fluid (SBF), to simulate body conditions, and deionized water, to evaluate the nature of the degradation products. The changes in mechanical and chemical properties were systematically characterized over 52 weeks dissolution time to determine the degradation mechanism and investigate strength retention by the bioresorbable glass fiber-reinforced PLDLA composite. The degradation mechanism was found to be a combination of surface and bulk erosion and does not follow the typical core-accelerated degradation mechanism of poly(α-hydroxyacids). Strength retention by bioresorbable glass fiber-reinforced PLDLA composites can be tailored by changing the oxide composition of the glass fibers, but the structure–property relationship of the glass fibers has to be understood and controlled so that the phenomenon of ion leaching can be utilized to control the degradation rate. Therefore, these high performance composites are likely to open up several new possibilities for utilizing resorbable materials in clinical applications which could not be realized in the past.  相似文献   
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The present population-based study examines associations between epilepsy and autism spectrum disorders (ASD). The cohort includes register data of 4,705 children born between 1987 and 2005 and diagnosed as cases of childhood autism, Asperger’s syndrome or pervasive developmental disorders—not otherwise specified. Each case was matched to four controls by gender, date of birth, place of birth, and residence in Finland. Epilepsy was associated with ASD regardless of the subgroup after adjusting for covariates. The associations were stronger among cases with intellectual disability, especially among females. Epilepsy’s age at onset was similar between the cases and controls regardless of the ASD subgroup. These findings emphasize the importance to examine the neurodevelopmental pathways in ASD, epilepsy and intellectual disability.  相似文献   
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We report the identification of OXA-48-producing Klebsiella pneumoniae, causing peritonitis in a cancer patient admitted to the Oncology Hospital in Sofia. The isolate had reduced susceptibility to carbapenems but remained susceptible to extended-spectrum cephalosporins. PCR and sequencing confirmed the presence of blaOXA-48 gene flanked by two intact copies of IS1999 on truncated ΔTn1999.1. This transposon was located on unusual non-typeable 29-kb plasmid that could be transferred only by transformation. Multilocus sequence typing (MLST) indicated the presence of the sequence type ST530.This is the first documented infection due to OXA-48-producing Enterobacteriaceae strain in Bulgaria.  相似文献   
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