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991.
Aging was associated with increased oxidation of DNA, RNA, and lipids in the cerebellum of male rats. DNA and lipid oxidation was reduced by lifelong (94 weeks) voluntary exercise on a running wheel. A reduction in cerebellar lipid oxidation, but not RNA or DNA oxidation, was observed following 3 months of moderate exercise or dietary supplementation of vitamin E, initiated at 18 months of age. The level of lipid oxidation correlated with measures of forelimb grip strength. The results indicate that lifelong exercise attenuates multiple molecular markers of age-related oxidative damage in the cerebellum. In addition, modest exercise initiated late in life can have a beneficial effect on lipid oxidation and motor function. 相似文献
992.
Bruton's tyrosine kinase (Btk): function, regulation, and transformation with special emphasis on the PH domain 总被引:2,自引:1,他引:1
993.
994.
Prevalence and correlates of human immunodeficiency virus testing and posttest counseling among outpatients with serious mental illness 总被引:1,自引:0,他引:1
This study examined the prevalence and correlates of receipt of human immunodeficiency virus (HIV) testing, test results, and posttest counseling among outpatients with serious mental illness at 3 public-sector facilities in Connecticut (N = 487). A substantial proportion (41.9%) reported never having been tested for HIV, including fully one-third of those who were "very afraid" of getting acquired immune deficiency syndrome. Independent correlates of HIV testing included younger age, felony criminal history, stronger therapeutic alliance with one's primary clinician, and increased drug problems and psychological distress. Of those tested, nearly all (96.5%) reported receiving the test results; however, only half (50.5%) reported receiving any posttest counseling. Independent correlates of posttest counseling included higher educational level, felony criminal history, and receipt of community-based case management services. Greater efforts are needed to increase HIV testing and counseling among persons with serious mental illness to better identify and care for HIV-positive individuals and potentially reduce future transmission of the virus in this vulnerable, at-risk population. 相似文献
995.
Maheedhar K Bhat RA Malini R Prathima NB Keerthi P Kushtagi P Krishna CM 《Photomedicine and laser surgery》2008,26(2):83-90
OBJECTIVE: To assess the efficacy of conventional Raman spectroscopy in combination with discriminating parameters, Mahalanobis distance, spectral residuals, and "limit test" methodology in differentiation of normal and malignant ovarian tissues. BACKGROUND DATA: Ovarian cancer is the second most common cancer among women and the leading cause of death among gynecologic malignancies. Initial laparotomy and subsequent frozen section analysis can influence the surgical management of ovarian cancers. Although frozen section pathology is sensitive and specific enough, interpretation is often subjective, time consuming, and requires highly skilled personnel. Raman spectroscopy is sensitive to biochemical variations in the samples, rapid, more objective, and amenable to multivariate statistical tools. It can therefore be an ideal tool for discrimination between normal and malignant ovarian tissues. METHODS: 72 Spectra from eight normal and seven malignant ovarian tissues were recorded by conventional near-infrared (NIR) Raman spectroscopy (excitation wavelength of 785 nm). Spectral data were analyzed by principal components analysis (PCA) and other discriminating parameters such as Mahalanobis distance, spectral residuals, and a multiparametric limit test approach. RESULTS: A mean malignant spectrum exhibits a broader amide I band, a stronger amide III band, a minor blue shift in the delta CH2 band, and a hump around 1480 cm(-1) compared to a normal spectrum. The normal spectra show relatively stronger peaks around the 855 and 940 cm(-1) region. Scores of factor 1 as well as Mahalanobis distance and spectral residuals gave good classification among the tissue types. The limit test approach provided unambiguous and objective discrimination. CONCLUSION: The findings of this study demonstrate the efficacy of conventional Raman spectroscopy and our statistical methodologies in discrimination of normal from malignant ovarian tissues. Prospectively, by evaluating the models and developing suitable fiberoptic probes, this technique could be useful in diagnosis during initial laparotomy. 相似文献
996.
A post-mortem study was conducted to find the incidence, morphological changes and distribution of lesions in the upper gastro-intestinal tract (GIT) in victims of head injury who had survived for 24 hours or longer. The study involved naked eye and microscopic examination of the mucosa of the upper gastro-intestinal tract. In this study all the victims of head injury who had survived one or more days showed definite evidence of damage to the lining of the stomach wall. The severity of the damage increased with survival time. The damage observed was in the form of congestion, mucosal haemorrhage, superficial erosions, and superficial ulcerations accompanied by frank haemorrhage. 相似文献
997.
Rao KV Rani A Reddy AV Bharathi CH Dandala R Naidu A 《Journal of pharmaceutical and biomedical analysis》2007,43(4):1476-1482
Three unknown impurities in Cefdinir bulk drug at levels below 0.2% (ranging from 0.05 to 0.2%) have been detected by high performance liquid chromatography (HPLC). These impurities were isolated from crude sample of Cefdinir using preparative HPLC. Based on the spectral data (NMR, IR and MS) the structures of these impurities were characterized as (6R, 7R)-7-[(z)-2-(2-aminothiazol-4-yl)-2-hydroxyiminoacetamido]-8-oxo-3-vinyl-5-thia-1-azabicyclo [4.2.0] oct-2-ene-2-carboxylic acid-5-oxide (I). (6R, 7R)-7-[(z)-2-(2-aminothiazol-4-yl)-2-hydroxyiminoacetamido]-8-oxo-3-vinyl-5-thia-1-azabi-cyclo [4.2.0] oct-3-ene-2-carboxylic acid (II). (6R, 7R)-7-[(z)-2-(2-aminothiazol-4-yl)-2-hydroxyiminoacetamido]-8-oxo-3-methyl-5-thia-1-azabicyclo-[4.2.0]oct-2-ene-2-carboxylic acid (III), respectively. The origin and structural elucidation of all impurities have been discussed. 相似文献
998.
Risk of incarceration between cohorts of veterans with and without mental illness discharged from inpatient units 总被引:1,自引:0,他引:1
Erickson SK Rosenheck RA Trestman RL Ford JD Desai RA 《Psychiatric services (Washington, D.C.)》2008,59(2):178-183
OBJECTIVE: This study examined the risk of incarceration among cohorts of veterans treated in the Department of Veterans Affairs (VA) Connecticut Healthcare System. Incarceration rates of persons with and without mental illness were compared and adjusted for various clinical and service utilization variables. Data were compared before and after the closure of over 80% of the Connecticut VA psychiatric inpatient beds in 1996. METHODS: Data from five annual cohorts of patients (1993-1997) treated in an inpatient unit in the VA Connecticut Healthcare System (N=36,385) were merged with state Department of Correction data. Logistic regression models were used to identify risk factors for incarceration. RESULTS: Bivariate analysis showed that incarceration rates were higher for VA patients with psychiatric disorders and with substance use disorders than for those without such diagnoses, but there were no significant increases in likelihood of incarceration over these years of extensive closures. In multiple logistic regression analysis only diagnoses of substance use disorders and major depression were independently associated with an increased likelihood of incarceration, whereas schizophrenia, personality disorders, and co-occurring psychiatric and substance use disorders were not independently associated with increased likelihood in multivariate analysis. CONCLUSIONS: Alcohol and drug problems appeared to account for much of the risk of incarceration among hospitalized veterans during the study period. Unlike in previous studies, schizophrenia and related psychotic disorders were not independently associated with an increased risk of incarceration. 相似文献
999.
Lin EY Li JF Bricard G Wang W Deng Y Sellers R Porcelli SA Pollard JW 《Molecular oncology》2007,1(3):288-302
Genetic depletion of macrophages in Polyoma Middle T oncoprotein (PyMT)-induced mammary tumors in mice delayed the angiogenic switch and the progression to malignancy. To determine whether vascular endothelial growth factor A (VEGF-A) produced by tumor-associated macrophages regulated the onset of the angiogenic switch, a genetic approach was used to restore expression of VEGF-A into tumors at the benign stages. This stimulated formation of a high-density vessel network and in macrophage-depleted mice, was followed by accelerated tumor progression. The expression of VEGF-A led to a massive infiltration into the tumor of leukocytes that were mostly macrophages. This study suggests that macrophage-produced VEGF regulates malignant progression through stimulating tumor angiogenesis, leukocytic infiltration and tumor cell invasion. 相似文献
1000.