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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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Aplasia of the major salivary glands is a rare condition due to an alteration in the development of the ectodermal tissue of the oral cavity often related to other craniofacial abnormalities or alteration of structures deriving from the first or second archial branch, in particular the lacrimal glands; it can be total or partial and determine clinical states ranging from an asymptomatic condition to a severe xerostomia. The accessory parotid tissue is similar to normal parotid tissue, completely independent from the main gland and susceptible to the same pathological disorders. We describe a very unusual case of an inflammatory disorder of accessory parotid tissue in a 44-year-old male patient with concomitant, and previously unknown, aplasia of the main ipsilateral parotid gland. We also discuss the role of imaging and conservative therapeutic modalities such as botulinum toxin therapy and, in the future, minimally invasive endoscopic-assisted resection in the management of such salivary disorder.  相似文献   
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The early-stage assessment of the physical stability of new monoclonal antibodies in different formulations is often based on high-throughput techniques that suffer from various drawbacks. Accordingly, new approaches that facilitate the protein formulation development can be of high value to the industry. In this study, a dynamic light scattering plate reader is used to measure the aggregation (by means of the increase in the hydrodynamic radius [Rh]) of monoclonal antibody samples that were subject to incubation and subsequent dilution from different concentrations of a denaturing agent, that is, guanidine hydrochloride. The increase in the Rh of the protein samples is dependent not only on the denaturant concentration used but also on the buffer in which the incubation/dilution was performed. We also compare the aggregation after dilution from a denaturant with other high-throughput stability-indicating methods and find good agreement between the techniques. The proposed approach to probe the physical stability of monoclonal antibodies in different formulation conditions offers a unique combination of features—it is isothermal, probes both the resistance to denaturant-induced unfolding and the colloidal protein stability, it is entirely label-free, does not rely on complex data evaluation, and requires very short instrument measurement time on standard equipment.  相似文献   
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