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1.
The aim of the study was to assess if lung function at birth predicts lung function at 2 yr and secondly, if lung function development was influenced by the common phenotypes of recurrent bronchial obstruction (rBO) or atopic eczema (AE) by 2 yr. Lung function was assessed at birth (n = 802) and at 2 yr within the prospective birth cohort study 'the Environment and Childhood Asthma Study' in Oslo. The 135 children with lung function measured at birth by tidal flow volume (TFV) loops and passive respiratory mechanics, who were included in a nested case-control study were reinvestigated at 2 yr with clinical examination, TFV loops (n = 90) (mean age 26.6 (3.7 s.d.) months), skin prick test and parental interview. Children were categorized into quartiles (lower, middle two, upper) according to time to peak tidal expiratory flow/total expiratory time (t(PTEF)/t(E)) at birth as well as clinical phenotype based on the presence of rBO and/or AE (ever) by 2 yr. The observed reduction in mean t(PTEF)/t(E) from birth to 2 yr within the quartiles, were not significantly different after controlling for 'regression to the mean'. t(PTEF)/t(E) at birth correlated significantly with t(PTEF)/t(E) at 2 yr, (r = 0.475, p < 0.001). Children with both rBO and AE by 2 yr had significantly lower t(PTEF)/t(E) at 2 yr (p = 0.002) and at birth (p = 0.027), compared with children with no rBO or AE. Clinical phenotype at 2 yr did not influence the change in t(PTEF)/t(E) from birth to 2 yr. This study demonstrates a clear tracking of lung function from birth, not influenced by rBO or AE by 2 yr.  相似文献   
2.
In a hospital-based case-referent study of 176 incident lung cancer cases, ascertained during a five-year period from two county hospitals, the role of asbestos exposure and smoking has been studied. Information on asbestos exposure was obtained from personal interviews, and allocated to four exposure categories, according to the intensity and duration of the exposure. Twenty-five percent of the cases and 10% of the referents had been moderately to heavily exposed to asbestos during their working career. A statistically significant trend in risk ratio related to the degree of exposure was observed, with a more than fourfold risk among the heavily exposed. The strongest association was found between asbestos exposure and small cell carcinoma, and the weakest association between asbestos exposure and adenocarcinoma. Very high risk ratios were observed among asbestos-exposed subjects who were heavy smokers, and the interaction observed between asbestos and smoking conformed more closely to a multiplicative model than to an additive one. The results suggest that the observed association between lung cancer and occupational exposures in this study was, to a large extent, due to asbestos exposure. Information on such exposure was missing in 90% of the medical records of these patients.  相似文献   
3.
Two conflicting theories exist concerning the stress pattern for the proximal lateral aspect of the human femur. According to the classic theory of Pauwels, a bending moment on the femur leads to compression medially and to tension laterally. The alternative theory is that muscle forces contribute to a moment-free loading of the femur, with both the medial and lateral cortices subjected to compression. To examine these theories, we measured the strain at the external surface of the proximal lateral aspect of the femur of two female patients undergoing surgery for “snapping hip syndrome.” During the surgical procedure, a strain-gauge rosette was bonded to the lateral aspect of the femur and the cortical strains were monitored while the patient performed a series of activities. In both patients, principle tensile strain increased significantly during one-legged stance, walking, and stair climbing as compared with that during two-legged stance. During each loading situation, the principal tensile strain was aligned within 22° to the longitudinal femoral axis. Dynamic strain measurements consistently revealed tensile axial strain at the lateral aspect of the femur during each activity. The present studv supports the classic bending theory of Pauwels and demonstrates that the proximal lateral aspect of the femur is subjected to tension during the stance phase of gait.  相似文献   
4.
Herpes virus hominis type 1 was isolated from the trigeminal ganglion (ganglion semilunare, gasservian) in three out of 20 randomly selected autopsies. Two of the three patients had been treated with immunosuppressive or cytostatic agents. Clinical signs of herpes infection were not observed during the previous 6 months. No virus was isolated from the facial ganglion (geniculate ganglion) in the same 20 cases. The findings are discussed in relation to the viral etiology of acute peripheral facial palsy.  相似文献   
5.
Journal of Public Health - Adolescents’ sleep duration has decreased over the past century; this is mainly caused by problems with falling asleep. Short sleep duration, poor sleep quality,...  相似文献   
6.
Ct and advanced computer-aided design techniques offer the means for designing customised femoral stems. Our aim was to determine the Hounsfield (HU) value of the bone at the corticocancellous interface, as part of the criteria for the design algorithm. We obtained transverse CT images from eight human cadaver femora. The proximal femoral canal was rasped until contact with dense cortical bone was achieved. The femora were cut into several sections corresponding to the slice positions of the CT images. After obtaining a computerised image of the anatomical sections using a scanner, the inner cortical contour was outlined and transferred to the corresponding CT image. The pixels beneath this contour represent the CT density of the bone remaining after surgical rasping. Contours were generated automatically at nine HU levels from 300 to 1100 and the mean distance between the transferred contour and each of the HU-generated contours was computed. The contour generated along the 600-HU pixels was closest to the inner cortical contour of the rasped femur and therefore 600 HU seem to be the CT density of the corticocancellous interface in the proximal part of cadaver femora. Generally, femoral bone with a CT density beyond 600 HU is not removable by conventional reamers. Thus, we recommend the 600 HU threshold as one of several criteria for the design of custom femoral implants from CT data.  相似文献   
7.
Results of gamma-ray measurements of selected tissues from a patient who was injected with Thorotrast almost 36 y ago are reported. The purposes of this study were: 1) to determine the relative tissue distribution and activities of specific radionuclides in the 232Th decay chain, specifically 228Ra (as measured by 228Ac), 212Pb, and 224Ra (measured directly and as measured by 212Pb), and 2) to evaluate the level of radioactive disequilibrium among the daughter products. The spleen and liver had the highest concentrations of radioactivity. Bone also appears to be a long-term sink for 232Th daughter products based on estimates from a small portion of one rib. Larynx and esophagus contained measurable activity, which may have been due to their proximity to the "Thorotrastoma." Radioactivity in the remaining measured tissues were low, as expected. Secular equilibrium could be demonstrated in bone, pancreas, larynx, esophagus, and breast. Significant disequilibrium was observed for spleen, liver, kidney, and red blood cells. Radioactivity measurements reported here will be useful in estimating radiation doses to selected tissues. Such dose estimates are valuable in refining current risk estimates (e.g., liver) and in identifying tissues at risk for further epidemiologic studies. These results, while consistent with other published studies, should be interpreted with caution since measurements were made on only one patient.  相似文献   
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Autism spectrum disorder (ASD) is a neurodevelopmental disorder afflicting about one in every 68 children. It is behaviorally diagnosed based on a triad of symptoms, including impairment in communication, impairment in sociability and abnormal and stereotypic behavior. The subjectivity of behavioral diagnosis urges the need for clinical biomarker tests to improve and complement ASD diagnosis and treatment. Over the past two decades, researchers garnered a broad range of biomarkers associated with ASD and often correlating with the severity of ASD, which includes metabolic and genetic biomarkers or neuroimaging abnormalities. Metabolic biomarkers are either involved in key pathways such as a trans-sulfuration pathway or produced due to the derangement of these pathways in the case of oxidative stress. Recent studies reported several genetic abnormalities related to ASD, encompassing various mechanisms, from copy number variations (CNVs) and single nucleotide polymorphisms (SNPs) to chromosomal anomalies. However, it is still premature to consider these genetic variants as true biomarkers for ASD, due to their low reproducibility and regional-specific nature. Herein, we comprehensively review state of the art about major biomarkers reported in ASD and the association of some biomarkers with ASD symptoms and severity. It is important to establish those biomarkers to be able to help in the diagnosis and to optimize the treatment of ASD.  相似文献   
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