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991.
Shreela V. Sharma Author Vitae Deanna M. HoelscherAuthor Vitae Steven H. KelderAuthor Vitae Pamela DiamondAuthor Vitae R. Sue DayAuthor Vitae Albert HergenroederAuthor Vitae 《Journal of the American Dietetic Association》2010,110(6):932-936
Calcium intake has been associated with promoting bone health in children and adolescents, thus preventing osteoporosis later in life. Behavior change such as increased calcium intake, as well as physiological factors such as bone quality, may be facilitated by psychosocial and environmental factors. The purpose of this study was to identify pathways by which psychosocial factors influence calcium intake and bone quality in middle school girls. The study design was cross-sectional. Baseline data from the Incorporating More Physical Activity and Calcium in Teens (IMPACT) study, collected in 2001-2003, were used. IMPACT was a 1.5-year nutrition and physical activity intervention study, designed to improve bone density in 717 middle school girls in Texas. Main outcome measures were calcium intake determined using mean milligrams of calcium consumed per day and number of glasses of milk consumed per day, and bone quality determined using a calcaneal stiffness index. Confirmatory factor analysis and path analysis were performed to identify the direct and indirect pathways used by various psychosocial factors such as knowledge, self-efficacy, outcome expectations, and milk availability at home, to influence calcium intake and bone quality. Results showed that knowledge of osteoporosis and calcium-rich foods had an indirect effect on calcium intake, with outcome expectations as the mediating variable (β=.035 and β=.03, respectively; P<0.05). Calcium self-efficacy had a significant indirect effect on calcium intake, with outcome expectations as the mediator (β=.085, P<0.05). None of the variables significantly influenced bone quality. Thus, several direct and indirect pathways used to influence calcium intake among adolescent girls were identified. These findings are critical for the development of effective interventions to promote calcium intake in this population. 相似文献
992.
IntroductionAtypical antipsychotic agents are widely used psychopharmacological interventions for autism spectrum disorders (ASDs). Among the atypical antipsychotic agents, risperidone has demonstrated considerable benefits in reducing several behavioral symptoms associated with ASDs. This meta-analysis examined research regarding the effectiveness of risperidone use among children with ASD using articles published since the year 2000.MethodsThe database for the analyses comprised 22 studies including 16 open-label and six placebo-controlled studies. Based on the quality, sample size, and study design of studies prior to 2000, the database was then restricted to articles published after the year 2000. Effect sizes were calculated for each reported measure within a study to calculate an average effect size per study.ResultsThe mean effect size for the database was 1.047 and the sample weighted mean effect size was 1.108, with a variance of 0.18.ConclusionsOutcome measures demonstrated mean improvement in problematic behaviors equaling one standard deviation, and thus current evidence supports the effectiveness of risperidone in managing behavioral problems and symptoms for children with ASD. Although Risperdal has several adverse effects, most are manageable or extremely rare. An exception is rapid weight gain, which is common and can create significant health problems. Overall, for most children with autism and irritable and aggressive behavior, risperidone is an effective psychopharmacological treatment. 相似文献
993.
The management of intradiploic CSF collection is controversial. Although it is a benign lesion, even then delay in diagnosis and treatment may lead to significant morbidity. The authors report a very rare case of giant posttraumatic intradiploic pseudomeningocele involving the occipital bone, occipital condyles, and clivus. The pathogenesis and management of intradiploic CSF collection are discussed. This 16-year-old boy presented with a history of enlarging swelling in the suboccipital region associated with headache, lower cranial nerve palsy, and features of high cervical compressive myelopathy. Investigations revealed a giant intradiploic lesion involving the occipital bone, condyles, and clivus associated with secondary basilar invagination, hydrocephalus, and syringomyelia. Intrathecal contrast administration did not reveal communication of intradiploic space with the subarachnoid space. A large occipital craniotomy was performed. A linear fracture and dural defect in the midline was identified, which was closed with fascial graft after removing the inner table of the skull. Cranioplasty was performed using the expanded calvarial bone. Ventriculoperitoneal shunt insertion was performed for hydrocephalus, and the patient improved remarkably. Posttraumatic intradiploic CSF collection, although a benign condition, may present with severe complications if treatment is delayed. Early diagnosis and treatment is essential. The authors suggest that this condition should be treated early, as for growing skull fractures. 相似文献
994.
Divya Sharma Manila Lather Cherry L. Dykes Amita S. Dang Tridibes Adak Om P. Singh 《Parasitology research》2016,115(1):323-328
995.
996.
Surface electromyogram (SEMG) is a complex signal and is influenced by several external factors/artifacts. The electromyogram signal from the stump of the subject is picked up through surface electrodes. It is amplified and artifacts are removed before digitising it in a controlled manner so that minimum signal loss occurs due to processing. As removing these artifacts is not easy, feature extraction to obtain useful information hidden inside the signal becomes a different process. This paper presents methods of analysing SEMG signals using discrete wavelet Transform (DWT) for extracting accurate patterns of the signals and the performance of the used algorithms is being analysed rigorously. The obtained results suggest a root mean square difference (RMSD) value for the denoising and quality of reconstruction of the SEMG signal. The result shows that the best mother wavelets for tolerance of noise are second order of symmlets and bior6.8. Results inferred that bior6.8 suitable for the classification and analysis of SEMG signals of different arm motions results in a classification accuracy of 88.90%. 相似文献
997.
Somatically Acquired LINE‐1 Insertions in Normal Esophagus Undergo Clonal Expansion in Esophageal Squamous Cell Carcinoma 下载免费PDF全文
Tara T. Doucet‐O'Hare Reema Sharma Nemanja Rodić Robert A. Anders Kathleen H. Burns Haig H. Kazazian Jr 《Human mutation》2016,37(9):942-954
Squamous cell carcinoma of the esophagus (SCC) is the most common form of esophageal cancer in the world and is typically diagnosed at an advanced stage when successful treatment is challenging. Understanding the mutational profile of this cancer may identify new treatment strategies. Because somatic retrotransposition has been shown in tumors of the gastrointestinal system, we focused on LINE‐1 (L1) mobilization as a source of genetic instability in this cancer. We hypothesized that retrotransposition is ongoing in SCC patients. The expression of L1 encoded proteins is necessary for retrotransposition to occur; therefore, we evaluated the expression of L1 open reading frame 1 protein (ORF1p). Using immunohistochemistry, we detected ORF1p expression in all four SCC cases evaluated. Using L1‐seq, we identified and validated 74 somatic insertions in eight tumors of the nine evaluated. Of these, 12 insertions appeared to be somatic, not genetically inherited, and sub‐clonal (i.e., present in less than one copy per genome equivalent) in the adjacent normal esophagus (NE), while clonal in the tumor. Our results indicate that L1 retrotransposition is active in SCC of the esophagus and that insertion events are present in histologically NE that expands clonally in the subsequent tumor. 相似文献
998.
Stratification of the aggressiveness of prostate cancer using pre‐biopsy multiparametric MRI (mpMRI) 下载免费PDF全文
Durgesh Kumar Dwivedi Rajeev Kumar Girdhar S. Bora Sanjay Thulkar Sanjay Sharma Siddhartha Datta Gupta Naranamangalam R. Jagannathan 《NMR in biomedicine》2016,29(3):232-238
Risk stratification, based on the Gleason score (GS) of a prostate biopsy, is an important decision‐making tool in prostate cancer management. As low‐grade disease may not need active intervention, the ability to identify aggressive cancers on imaging could limit the need for prostate biopsies. We assessed the ability of multiparametric MRI (mpMRI) in pre‐biopsy risk stratification of men with prostate cancer. One hundred and twenty men suspected to have prostate cancer underwent mpMRI (diffusion MRI and MR spectroscopic imaging) prior to biopsy. Twenty‐six had cancer and were stratified into three groups based on GS: low grade (GS ≤ 6), intermediate grade (GS = 7) and high grade (GS ≥ 8). A total of 910 regions of interest (ROIs) from the peripheral zone (PZ, range 25–45) were analyzed from these 26 patients. The metabolite ratio [citrate/(choline + creatine)] and apparent diffusion coefficient (ADC) of voxels were calculated for the PZ regions corresponding to the biopsy cores and compared with histology. The median metabolite ratios for low‐grade, intermediate‐grade and high‐grade cancer were 0.29 (range: 0.16, 0.61), 0.17 (range: 0.13, 0.32) and 0.13 (range: 0.05, 0.23), respectively (p = 0.004). The corresponding mean ADCs (×10–3 mm2/s) for low‐grade, intermediate‐grade and high‐grade cancer were 0.99 ± 0.08, 0.86 ± 0.11 and 0.69 ± 0.12, respectively (p < 0.0001). The combined ADC and metabolite ratio model showed strong discriminatory ability to differentiate subjects with GS ≤ 6 from subjects with GS ≥ 7 with an area under the curve of 94%. These data indicate that pre‐biopsy mpMRI may stratify PCa aggressiveness noninvasively. As the recent literature data suggest that men with GS ≤ 6 cancer may not need radical therapy, our data may help limit the need for biopsy and allow informed decision making for clinical intervention. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
999.
Sharma R Yellowley CE Civelek M Ainslie K Hodgson L Tarbell JM Donahue HJ 《Annals of biomedical engineering》2002,30(3):371-378
Vascular smooth muscle cells (VSM) are normally exposed to transmural fluid flow shear stresses, and after vascular injury, blood flow shear stresses are imposed upon them. Since Ca2+ is a ubiquitous intracellular signaling molecule, we examined the effects of fluid flow on intracellular Ca2+ concentration in rat aortic smooth muscle cells to assess VSM responsiveness to shear stress. Cells loaded with fura 2 were exposed to steady flow shear stress levels of 0.5–10.0 dyn/cm2 in a parallel-plate flow chamber. The percentage of cells displaying a rise in cytosolic Ca2+ ion concentration ([Ca2+]i) increased in response to increasing flow, but there was no effect of flow on the ([Ca2+]i) amplitude of responding cells. Addition of Gd3+ (10 M) or thapsigargin (50 nM) significantly reduced the percentage of cells responding and the response amplitude, suggesting that influx of Ca2+ through ion channels and release from intracellular stores contribute to the rise in ([Ca2+]i) in response to flow. The addition of nifedipine (1 or 10 M) or ryanodine (10 M) also significantly reduced the response amplitude, further defining the role of ion channels and intracellular stores in the Ca2+ response. © 2002 Biomedical Engineering Society.
PAC2002: 8716Uv, 8719Uv, 8716Dg, 8719Ff 相似文献
1000.
Quantitative Analysis of Mycobacterial and Propionibacterial DNA in Lymph Nodes of Japanese and European Patients with Sarcoidosis 总被引:10,自引:0,他引:10 下载免费PDF全文
Yoshinobu Eishi Moritaka Suga Ikuo Ishige Daisuke Kobayashi Tetsuo Yamada Tamiko Takemura Touichiro Takizawa Morio Koike Shoji Kudoh Ulrich Costabel Josune Guzman Gianfranco Rizzato Marcello Gambacorta Ronald du Bois Andrew G. Nicholson Om P. Sharma Masayuki Ando 《Journal of clinical microbiology》2002,40(1):198-204
The cause(s) of sarcoidosis is unknown. Mycobacterium spp. are suspected in Europe and Propionibacterium spp. are suspected in Japan. The present international collaboration evaluated the possible etiological links between sarcoidosis and the suspected bacterial species. Formalin-fixed and paraffin-embedded sections of biopsy samples of lymph nodes, one from each of 108 patients with sarcoidosis and 65 patients with tuberculosis, together with 86 control samples, were collected from two institutes in Japan and three institutes in Italy, Germany, and England. Genomes of Propionibacterium acnes, Propionibacterium granulosum, Mycobacterium tuberculosis, Mycobacterium avium subsp. paratuberculosis, and Escherichia coli (as the control) were counted by quantitative real-time PCR. Either P. acnes or P. granulosum was found in all but two of the sarcoid samples. M. avium subsp. paratuberculosis was found in no sarcoid sample. M. tuberculosis was found in 0 to 9% of the sarcoid samples but in 65 to 100% of the tuberculosis samples. In sarcoid lymph nodes, the total numbers of genomes of P. acnes or P. granulosum were far more than those of M. tuberculosis. P. acnes or P. granulosum was found in 0 to 60% of the tuberculosis and control samples, but the total numbers of genomes of P. acnes or P. granulosum in such samples were less than those in sarcoid samples. Propionibacterium spp. are more likely than Mycobacteria spp. to be involved in the etiology of sarcoidosis, not only in Japanese but also in European patients with sarcoidosis. 相似文献