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101.
Carolyn A Chew-Graham Karina Lovell Chris Roberts Robert Baldwin Michael Morley Alistair Burns David Richards Heather Burroughs 《The British journal of general practice》2007,57(538):364-370
BACKGROUND: Depression is the most common mental health disorder in people aged over 65 years. Late-life depression is associated with chronic illness and disability. AIM: To investigate the feasibility of a collaborative care model for depression in older people in a primary care setting. DESIGN OF STUDY: Randomised controlled trial with 16-weeks follow up. SETTING: A primary care trust in Manchester. METHOD: Participants were 105 people aged 60 years or older who scored 5 or more on the Geriatric Depression Scale; 53 were randomly allocated to an intervention group and 52 to a usual care group. The intervention group received care managed by a community psychiatric nurse who delivered an intervention comprising a facilitated self-help programme with close liaison with primary care professionals and old-age psychiatry according to a defined protocol. The usual care group received usual GP care. A nested qualitative study explored the views of the health professionals and patients regarding the acceptability and effectiveness of the intervention. RESULTS: The main outcome measure was recovery from depression. Patients in the intervention group were less likely to suffer from major depressive disorder at follow up compared with usual care (0.32, 95% confidence = interval = 0.11 to 0.93, P = 0.036). The qualitative component of the study demonstrated the acceptability of the intervention to patients. CONCLUSION: A model of collaborative care for older people with depression, used in a primary care setting with a facilitated self-help intervention is more effective than usual GP care. This study demonstrates that the implementation of a collaborative care model is feasible in UK primary care and that the intervention is effective and acceptable to patients. 相似文献
102.
Prabhakar V Grinstaff MW Alarcon J Knors C Solan AK Niklason LE 《Journal of biomedical materials research. Part A》2003,67(1):303-311
Techniques have been developed to culture bovine or porcine vascular cells on polyglycolic acid (PGA) scaffolds to form engineered vessels. Previously, it was shown that smooth muscle cells (SMCs) that were in close proximity to PGA remnants after 8 weeks of culture had lower expression of SMC markers of differentiation and were more mitotic compared with SMCs that were distant from polymer residuals. Modifications of PGA were explored as a means to minimize residual polymer fragments after culture. To hasten degradation, polymer was treated with heat, NaOH, or gamma-irradiation. Differential scanning calorimetry, mass and tensile strength degradation, and inherent viscosity were used to assess polymer characteristics. When polymer was maintained in aqueous conditions, tensile strength of treated PGA degraded to zero within 3 weeks for each treatment. Engineered vessel constructs cultured on NaOH and gamma-treated polymer displayed smooth muscle alpha-actin throughout the vessel wall. Scaffold treatment impacted graft morphology, cellular differentiation, and mechanical integrity. 相似文献
103.
Mode of delivery and risk of developing allergic disease 总被引:3,自引:0,他引:3
McKeever TM Lewis SA Smith C Hubbard R 《The Journal of allergy and clinical immunology》2002,109(5):800-802
The aim of this study was to quantify the relationship between mode of delivery and subsequent incidence of allergic disease. The analysis is based on data derived from a birth cohort of 24,690 children who contributed data to the West Midlands General Practice Research Database. We found no convincing evidence to suggest that babies born by caesarean, forceps, or breech delivery had an increased risk of developing allergic disease. 相似文献
104.
Stephan G. M. Meuwissen Anne Bosma Evert van Donk Reinier Waalewijn Gerard Pals Jan C. Pronk Aldur W. Eriksson Hendrik Mullink Chris J. L. M. Meijer 《Virchows Archiv : an international journal of pathology》1988,413(1):11-16
Summary No data are available on the localization of Pepsinogen A (PGA=PG I) and Pepsinogen C (PGC=PG II) positive cells in Barrett's epithelium. Endoscopic biopsy specimens were taken from the columnar epithelium from 23 patients (n=93), and in addition from the cardia from eight healthy control subjects (n=38). The tissue was stained by the immunoperoxidase technique with specific anti-pepsinogen antisera, and double immunostained for PGA and PGC. In the Barrett's epithelium PGA was found in 28 out of 93 biopsy specimens (30.1%) and PGC in 55 out of 93 (59.1%). Chief cells always stained both for PGA and PGC, while clear mucous cells were often PGA– and PGC+. PGA+ and PGC+ cells were found each in 100% of the biopsy specimens with fundic type epithelium, in 21.7% and 70.7% of biopsy specimens with junctional type, in 0% and 26.1% of biopsy specimens with specialized epithelium and in 12.5% and 43.5% of biopsy specimens with mixed junctional/specialized features respectively. Dysplastic epithelium stained always negatively with both anti-pepsinogen antisera. In most control cardia biopsy specimens PGA as well as PGC were demonstrable; occasionally clear mucous glands were PGA– and PGC+.It is concluded that pepsinogen-containing cells can be accurately identified in the Barrett's epithelium; their presence seems related to the histological cell type. Identification of pepsinogen positive cells may contribute to a more accurate morphological classification of the Barrett's epithelium.Presented in part at the Annual Meeting of the American Gastroenterological Association, San Francisco, May 1986 相似文献
105.
Acute liver failure was induced in rats by CCl4 administration and its effects on the hepatic Krebs cycle and gluconeogenic fluxes were evaluated in situ by 13C NMR isotopomer analysis of hepatic glucose following infusion of [U-13C]propionate. In fed animals, CCl4 injury caused a significant increase in relative gluconeogenic flux from 0.80+/-0.10 to 1.34 +/-0.24 times the flux through citrate synthase (p<0.01). In 24-h fasted animals, CCl4-injury also significantly increased relative gluconeogenic flux from 1.36+/-0.16 to 1.80+/-0.22 times the flux through citrate synthase (p<0.01). Recycling of PEP via pyruvate and oxaloacetate was extensive under all conditions and was not significantly altered by CCl4 injury. CCl4 injury significantly reduced hepatic glucose output by 26% (42.8+/-7.3 vs 58.1+/-2.4 micromol/kg/min, p=0.005), which was attributed to a 26% decrease in absolute gluconeogenic flux from PEP (85.6+/-14.6 vs 116+/-4.8 micromol/kg/min, p<0.01). These changes were accompanied by a 47% reduction in absolute citrate synthase flux (90.6+/-8.0 to 47.6+/-8.0 micromol/kg/min, p<0.005), indicating that oxidative Krebs cycle flux was more susceptible to CCl4 injury. The reduction in absolute fluxes indicate a significant loss of hepatic metabolic capacity, while the significant increases in relative gluconeogenic fluxes suggest a reorganization of metabolic activity towards preserving hepatic glucose output. 相似文献
106.
J. S. Alexander T. Dayton C. Davis Stephen Hill T. Haller Jackson Orest Blaschuk Matthew Symonds Naotsuka Okayama Chris G. Kevil F. Stephen Laroux S. M. Berney D. Kimpel 《Inflammation》1998,22(6):573-582
T-lymphocytes routinely traffic from the lymphoid and vascular compartments to the tissues during immune surveillance and inflammatory responses. This egress occurs without compromising endothelial barrier, which is maintained by tight junctions (zonula occludens). We report that T-lymphocytes up-regulate the expression of occludin, a major component of the tight junction in response to stimulation with phorbol ester (PMA) + calcium ionophore, CD3 antibody or T-cell receptor (TCR) antibody. Only activated T-lymphocytes express occludin; this adhesion molecule is nearly absent in resting T-lymphocytes. By immunofluorescence, occludin is seen in lymphocyte aggregates, but does not appear to mediate aggregation since only 50% of the cells in these clusters express occludin. Occludin is expressed between 8 and 24 h following stimulation, and persists for at least 48 h. These data indicate that activated T cells produce occludin which may regulate lymphocyte adhesion and trafficking. 相似文献
107.
Amara RR Ibegbu C Villinger F Montefiori DC Sharma S Nigam P Xu Y McClure HM Robinson HL 《Virology》2005,343(2):246-255
Here, we study immune responses in four DNA/MVA-vaccinated macaques following an SHIV-89.6P challenge and a subsequent CD8 cell depletion. Both post-challenge and post-depletion peaks of viremia contracted with the expansion, or re-emergence, of CD8 T cells. Post-depletion, CD8 cells expanded in the presence of higher levels of neutralizing Ab and CD4 help than post-challenge and had superior maturational characteristics as measured by expression of the anti-apoptotic protein Bcl-2, the IL-7 receptor CD127 and co-production of IFN-gamma and IL-2. Pre-challenge and pre-depletion titers of neutralizing Ab correlated inversely with peaks of viremia and directly with peaks for anti-viral CD4 cells. Thus, our results reveal CD8 cells playing a central role, and neutralizing Ab, a supporting role in SHIV-89.6P control. They also suggest a dynamic relationship between neutralizing Ab, antigen load and anti-viral CD4 cells in the maturation of high-quality anti-viral CD8 T cells. 相似文献
108.
Linear regression of eye velocity on eye position and head velocity suggests a common oculomotor neural integrator 总被引:3,自引:0,他引:3
Goldman MS Kaneko CR Major G Aksay E Tank DW Seung HS 《Journal of neurophysiology》2002,88(2):659-665
The oculomotor system produces eye-position signals during fixations and head movements by integrating velocity-coded saccadic and vestibular inputs. A previous analysis of nucleus prepositus hypoglossi (nph) lesions in monkeys found that the integration time constant for maintaining fixations decreased, while that for the vestibulo-ocular reflex (VOR) did not. On this basis, it was concluded that saccadic inputs are integrated by the nph, but that the vestibular inputs are integrated elsewhere. We re-analyze the data from which this conclusion was drawn by performing a linear regression of eye velocity on eye position and head velocity to derive the time constant and velocity bias of an imperfect oculomotor neural integrator. The velocity-position regression procedure reveals that the integration time constants for both VOR and saccades decrease in tandem with consecutive nph lesions, consistent with the hypothesis of a single common integrator. The previous evaluation of the integrator time constant relied upon fitting methods that are prone to error in the presence of velocity bias and saccades. The algorithm used to evaluate imperfect fixations in the dark did not account for the nonzero null position of the eyes associated with velocity bias. The phase-shift analysis used in evaluating the response to sinusoidal vestibular input neglects the effect of saccadic resets of eye position on intersaccadic eye velocity, resulting in gross underestimates of the imperfections in integration during VOR. The linear regression method presented here is valid for both fixation and low head velocity VOR data and is easy to implement. 相似文献
109.
Frequency of cytokine polymorphisms in populations from western Europe,Africa, Asia,the Middle East and South America 总被引:15,自引:0,他引:15
Meenagh A Williams F Ross OA Patterson C Gorodezky C Hammond M Leheny WA Middleton D 《Human immunology》2002,63(11):1055-1061
PCR-SSOP identification procedures for IL-2, IL-6, IL-10, TNF-alpha and TNF-beta cytokine polymorphisms have been developed. Application of the procedures to a range of diverse geographically distributed populations has identified ethnic differences within the groups studied. Five populations were investigated, Northern Ireland, South African Zulu, Omani, Singapore Chinese and Mexican Mestizos. 相似文献