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Surveillance of norovirus infections in sporadic cases of pediatric gastroenteritis admitted to a main hospital in Northern Italy during a full-year period (2002) showed that noroviruses (10.4%) were the second most common causative viral agent, following rotaviruses (21.1%), and noroviruses (81%) were mostly implicated in mixed infections. The epidemic period of norovirus was September-December, with September and November as months of major prevalence (33.3 and 38.5%, respectively). Six distinct norovirus genotypes were detected (GI.7, GII.1, GII.2, GII.4, GII.7, GII, not assigned named GIIb), and the predominant genotype was GII.4. A "new GII.4 2002 variant" accounted for 82.9% of total strains. Since the severity of norovirus symptoms does not usually require admission to hospital, the burden of norovirus disease in the general children population may be much higher than that suggested by the present hospital-based investigation.  相似文献   
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Molecular markers can serve as diagnostic tools to support pathological analysis in thyroid neoplasms. However, because the same markers can be observed in some benign thyroid lesions, additional approaches are necessary to differentiate thyroid tumor subtypes, prevent overtreatment and tailor specific clinical management. This applies particularly to the recently described variant of thyroid cancer referred to as noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP). This variant has an estimated prevalence of 4.4% to 9.1% of all papillary thyroid carcinomas worldwide. We studied 60 thyroid lesions: 20 classical papillary thyroid carcinoma (CPTC), 20 follicular variant of PTC (FVPTC) and 20 NIFTP. We examined morphological and molecular features to identify parameters that can differentiate NIFTP from the other PTC subtypes. When blindly investigating the nuclear architecture of thyroid neoplasms, we observed that NIFTP has significantly longer telomeres than CPTC and FVPTC. Super-resolved 3D-structured illumination microscopy demonstrated that NIFTP is heterogeneous and that its nuclei contain more densely packed DNA and smaller interchromatin spaces than CPTC and FVPTC, a pattern that resembles normal thyroid tissue. These data are consistent with the observed indolent biological behavior and favorable prognosis associated with NIFTP, which lacks BRAFV600E mutations. Of note, next-generation thyroid oncopanel sequencing was unable to distinguish the thyroid cancer histotypes in our study cohort. In summary, our data suggest that 3D nuclear architecture can be a powerful analytical tool to diagnose and guide clinical management of NIFTP.  相似文献   
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Several factors which affect bone density and predict risk of osteoporosis (e.g., ethnic origin, amenorrhea) are reportedly associated with a higher incidence of stress fracture in active premenopausal women. The authors surveyed 2,312 active duty Army women for the prevalence of ever having been diagnosed ("told by a doctor") with a stress fracture (16.1% of respondents) and examined the relationship between surveyable risk factors for low bone density and this self-reported stress fracture history (self-reported SF). Current smoking, previous history of amenorrhea (menses absent greater than 6 months), and known family history of osteoporosis were significantly associated with self-reported SF, while black ethnic origin was a protective factor. These data suggest hypotheses of stress fracture pathogenesis in Army women which bear further testing.  相似文献   
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A real-time polymerase chain reaction (PCR) assay was evaluated in comparison with the combination of conventional methods (microscopic examination and antigen detection assay) during the period 2006 to 2008 on 771 fecal samples belonging to 386 patients to assess its usefulness for an accurate laboratory diagnosis of giardiasis. The real-time PCR assay detected Giardia intestinalis DNA in 195 samples (106 patients), including 26 samples (21 patients) negative by the conventional assays. Among the 21 patients, in 8 cases, giardiasis was previously diagnosed also by conventional methods in additional samples of the same patients, whereas in 13, it would have been undiagnosed if real-time PCR assay was not used. The real-time PCR assay demonstrated a detection limit of 2 cysts per reaction and 100% specificity and sensitivity compared to conventional methods. A genotype analysis targeting the β-giardin gene allowed to identify 53 samples (23 patients) containing genotype A and 59 samples (45 patients) containing genotype B.  相似文献   
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Foetal hydrops occurs when a certain amount of interstitial fluid, produced by capillary ultrafiltration, overcomes the amount of interstitial fluid that returns to the blood circulation through the lymphatic system. Hydrops is classified as immune (IH) due to the presence of circulating maternal antibodies against the foetal red blood cell's antigens, and non-immune (NIH) that includes all the other causes of hydrops. This classification is still valid, but only under a clinical point of view because they differ in aetiology and management. In this article the management of a case of non-immune foetal hydrops is described, in which, unlike most other cases of non-immune foetal hydrops, the foetus survived.  相似文献   
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Bicycle riding is a popular form of recreation, fitness and transportation in many areas of the world. Traumatic injuries associated with bicycle riding have been documented and intervention strategies have been successful. This has not been the case for non-traumatic injuries. The prevalence of non-traumatic bicycle injuries can be as high as 85%. The most common sites for non-traumatic cycling-related injuries include the knee, neck/shoulder, hands, buttock and perineum. Two categories of injuries that may have the greatest impact on disability include ulnar and median nerve palsy, and erectile dysfunction. Injury prevention strategies have been proposed to reduce non-traumatic injuries but these strategies remain untested.  相似文献   
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