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81.
82.
Clinical and Experimental Medicine - The TIRADS is a scoring system used for the selection of nodules for FNA and classification of the risk of malignancy based on ultrasound characteristics. The...  相似文献   
83.
BACKGROUND: Antibodies (Abs) to alpha-elastin (elastin breakdown product) and tropoelastin (elastin precursor) are found in the serum of all human subjects and correlate with their respective serum peptide levels; however, peptide levels vary with age and some disease states. This study was undertaken to determine if serum elastin Abs, peptides, and elastin metabolism were altered in autoimmune diseases by detecting a changing ratio of serum anti-alpha:tropoelastin Ab levels. METHODS: Serum from patients with a variety of connective tissue diseases, including 28 with systemic lupus erythematosus (SLE), 24 with scleroderma, 18 with rheumatoid arthritis (RA), 10 with polymyositis, and 39 with vasculitis, was compared with serum from 19 age-matched healthy subjects for levels of antitropoelastin and anti-alpha-elastin Abs. RESULTS: We found an increase in IgG anti-alpha-elastin and a decrease in antitropoelastin Abs in the sera of patients with scleroderma (p < .02 and .00005) and SLE (p < .006 and .011). There was also a marked increase in anti-alpha-elastin Abs in patients with polyarteritis nodosa (p < .0005) and decreases in antitropoelastin Abs in patients with RA (p < .05), polymyositis (p < .01), and a variety of other vasculidities (p < .0003). CONCLUSIONS: Abnormal variations in elastin metabolism may be detected in several connective tissue diseases by measuring ratios of alpha- and tropoelastin IgG Abs as markers of elastin degradation and synthesis.  相似文献   
84.
This article describes one step in the process that was undertaken to prepare for the introduction of evidence-based practice (EBP) into the curriculum across the Bachelor of Science in Nursing, Master of Science in Nursing, and Doctor of Philosophy programs, as well as the programs that were under development, Clinical Nurse Leader and Doctor of Nursing Practice, at the University of Pittsburgh School of Nursing. Expected research competencies were identified for each level or academic year within each program. Based on these competencies, recommendations on how to modify the curriculum into one that would support students' acquisition and development of the skills necessary to be successful in matriculating through an EBP curriculum were developed. Evaluation mechanisms for the achievement of these competencies vary across the academic programs and will include performance on capstone projects, comprehensive examinations, and program milestones for doctoral students. The establishment of evidence-based competencies provided a foundation for the development of new teaching approaches and the curricular revisions across the three academic programs. Thus, the University of Pittsburgh model of educating for EBP is based on a sequential layering of research competencies throughout the curriculum.  相似文献   
85.
Atrophy and fatty infiltration of lower extremity muscle after spinal cord injury (SCI) predisposes individuals to metabolic syndrome and related diabetes and cardiovascular disease. The objective of this study was to prospectively measure changes in muscle atrophy and fat content of distal lower extremity muscles and explore related factors in a cohort of adults with chronic SCI and diverse impairments. Muscle cross-sectional area and density were calculated from peripheral quantitative computed tomography scans of the 66% site of the calf from 70 participants with chronic SCI (50 male, mean age 49 years, C2-T12, American Spinal Injury Association Impairment Scale A-D) at study enrollment and annually for 2 years. Mixed-model repeated measures analysis of variance (rANOVA) examined longitudinal changes in muscle area and density, and regression analyses explored factors related to muscle changes using 16 potential correlates selected a priori. A high degree of individual variation in muscle area and density change was observed over 2 years (range: 8.5 to???22.6?cm2; 6.4 to??8.6?mg/cm3). Repeated measures analysis of variance revealed significant reductions in muscle area (estimated mean difference [95% confidence intervals] ?1.76 [?3.29?to ?0.23]) cm2, p?=?0.025) and density (?1.04 [?1.94 to??0.14] mg/cm3, p?<?0.024); however, changes in area were not significant with outliers removed. Regression analyses explained a small proportion of the variability in muscle density change; however, none of the preselected variables were significantly related to changes in muscle density after post hoc sensitivity analyses. Lower extremity muscle size and fat content may not reach a “steady-state” after chronic SCI. Progressive atrophy and fatty infiltration of lower extremity muscle may have adverse implications for metabolic syndrome and cardiovascular disease risk and related mortality after chronic SCI.  相似文献   
86.
The objective of this study was to compare the test-retest precision error for peripheral quantitative computed tomography (pQCT)-derived marrow density and marrow area segmentation at the tibia using 3 software packages. A secondary analysis of pQCT data in young adults (n?=?18, mean?±?standard deviation 25.4?±?3.2?yr), older adults (n?=?47, 71.8?±?8.2?yr), and individuals with spinal cord injury (C1–T12 American Spinal Injury Association Impairment Scale, classes A–C; n?=?19, 43.5?±?8.6?yr) was conducted. Repeat scans of the tibial shaft (66%) were performed using pQCT (Stratec XCT2000). Test-retest precision errors (root mean square standard deviation and root mean square coefficient of variation [RMSCV%]) for marrow density (mg/cm3) and marrow area (mm2) were reported for the watershed-guided manual segmentation method (SliceOmatic version 4.3 [Sliceo-WS]) and the 2 threshold-based edge detection methods (Stratec version 6.0 [Stratec-TB] and BoneJ version 1.3.14 [BoneJ-TB]). Bland-Altman plots and 95% limits of agreement were computed to evaluate test-retest discrepancies within and between methods of analysis and subgroups. RMSCV% for marrow density segmentation was >5% for all methods across subgroups (Stratec-TB: 12.2%–28.5%, BoneJ-TB: 14.5%–25.2%, and Sliceo-WS: 10.9%–23.0%). RMSCV% for marrow area segmentation was within 5% for all methods across subgroups (Stratec-TB: 1.9%–4.4%, BoneJ-TB: 2.6%–5.1%, and Sliceo-WS: 2.4%–4.5%), except using BoneJ-TB in older adults. Intermethod discrepancies in marrow density appeared to be present across the range of marrow density values and did not differ by subgroup. Intermethod discrepancies varied to a greater extent for marrow area and were found to be more frequently at mid- to higher-range values for those with spinal cord injury. Precision error for pQCT-derived marrow density segmentation exceeded 5% for all methods of analysis across a range of bone mineral densities and fat infiltration, whereas precision error for marrow area segmentation ranged from 2% to 5%. Further investigation is necessary to determine alternative acquisition and analysis methods for pQCT-derived marrow segmentation.  相似文献   
87.
Increasing evidence indicates that radiation-induced genomic instability plays an important role in the development of cancer. However, radiation quality and genetic background can influence the outcome. The goal of this study was to quantify radiation-induced changes in lymphocyte populations in mouse strains known to differ in susceptibility to genomic instability (C57BL/6, resistant; CBA/Ca, susceptible). The effects of whole-body exposure to γ-rays and protons, with and without aluminum shielding, were compared. Total radiation doses of 0, 0.1, 0.5, and 2.0 Gy were delivered and subsets of mice from each group were euthanized on days 1 and 30 after exposure for spleen and bone marrow analyses. In the spleen on day 1, lymphocyte counts were decreased (p<0.05) in C57, but not CBA, mice irradiated with 2 Gy. By day 30 in the C57 strain, counts were still low in the group exposed to 2 Gy shielded protons. Some strain- and radiation-dependent differences were also noted in percentages of specific lymphocyte populations (T, B, NK) and the CD4:CD8 ratio. In bone marrow, percentages of stem/progenitor cells (CD34(+), Ly-6A/E(+), CD34(+)Ly-6A/E(+)) were generally highest 1 day after 2 Gy irradiation, regardless of strain and radiation type. Based on dUTP incorporation, bone marrow cells from C57 mice had consistently higher levels of DNA damage on day 30 after irradiation with doses less than 2 Gy, regardless of quality. Annexin V binding supported the conclusion that C57 bone marrow cells were more susceptible to radiation-induced apoptosis. Overall, the data indicate that leukocytes of CBA mice are less sensitive to the effects of high-linear energy transfer radiation (shielded protons) than C57 mice, a phenomenon consistent with increased possibility for genomic instability and progression to a malignant cell phenotype after sublethal damage.  相似文献   
88.
The PPARγ agonist troglitazone (TG) induced an increased incidence of hemangiosarcomas in mice but was not carcinogenic in rats. In contrast, pioglitazone (PIO) did not induce hemangiosarcomas or any other tumors in mice. We previously demonstrated that TG increased the proliferation of endothelial cells (ECs) in liver and adipose tissue in mice, and acted as a mitogenic stimulant and an inhibitor of apoptosis in vitro in mouse, but not human, ECs. In the present study, we investigated whether TG had any effect on the proliferation of ECs in rats. We also evaluated the in vivo and in vitro effects of PIO on ECs in mice. In rats, TG did not increase the Ki-67 labeling index (LI) of ECs in liver or adipose tissue at doses used in the two-year bioassay, and did not increase hepatocyte proliferation. PIO administered to mice did not increase the Ki-67 LI of hepatocytes or ECs in liver or white adipose tissue, but slightly increased the EC proliferation in brown adipose tissue. PIO was slightly mitogenic on cultured mouse ECs after 3 days of treatment but not after 6 days, and there was no inhibition of apoptosis, in contrast to what was seen with TG. The data support the conclusion that sustained EC proliferation in mice is necessary, for the induction of hemangiosarcomas by TG, and these short-term and long-term effects are not seen with TG in the rat or with PIO in mice, treatments that also are not related to the induction of hemangiosarcomas in two-year bioassays.  相似文献   
89.
ObjectivesThe objective of this study was to examine the associations between (a) childhood maltreatment (i.e., physical abuse, sexual abuse, and neglect) and subsequent illicit drug use and (b) childhood maltreatment and drug-related problems in young adulthood.MethodsWave 1 and Wave 3 public-use data from the National Longitudinal Study of Adolescent Health were used. Logistic regressions, controlling for adolescent drug use and other important family and peer contextual processes, were estimated to determine the associations between (a) childhood maltreatment experiences and subsequent illicit drug use and (b) childhood maltreatment and drug-related problems in young adulthood.ResultsAmong the participants, 31.9% reported some form of childhood maltreatment. Childhood physical abuse was associated with a 37% (OR = 1.37; 95% CI = 1.04, 1.80) increase in illicit drug use during the 30 days prior to the Wave 3 survey, a 48% (OR = 1.48; 95% CI = 1.16, 1.89) increase in illicit drug use during the year prior to the Wave 3 survey, and a 96% (OR = 1.96; 95% CI = 1.40, 2.76) increase in drug-related problems in young adulthood. The latter two associations persisted even after controlling for illicit drug use in adolescence. Neglect among females was associated with a higher likelihood of past year illicit drug use in young adulthood (OR = 1.31; 95% CI = 1.002, 1.71). However, this association was not significant once the effect of illicit drug use in adolescence was statistically controlled for.ConclusionsThe present findings suggest that childhood maltreatment is related to subsequent illicit drug use and drug-related problems in young adulthood and that some of these associations differ by gender. Implications for preventive intervention are discussed.  相似文献   
90.
Amphetamine use and abuse carry with it substantial social costs. Although there is a perception that amphetamine users are more difficult to treat than other substance users, drug courts have been used to effectively address drug-related crimes and hold the potential to lessen the impact of amphetamine abuse through efficacious treatment and rehabilitation. The objective of this study was to identify predictors of drug court outcome among amphetamine-using participants. A drug court database was obtained (N = 540) and amphetamine-using participants (n= 341) identified. Multivariate binary regression models run for the amphetamine-using participants identified being employed and being a parent as predictive of successful completion of the program, whereas being sanctioned to jail during the program was inversely related to program completion.  相似文献   
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