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Barbara Resnick Denise Orwig Janet Yu-Yahiro William Hawkes Michelle Shardell J. Richard Hebel Sheryl Zimmerman Justine Golden Michele Werner Jay Magaziner 《Annals of behavioral medicine》2007,34(1):67-76
Background: Exercise is an important strategy with potential to improve recovery in older adults following a hip fracture.Purpose: The purpose of this study was to test the impact of a self-efficacy based intervention, the Exercise Plus Program, and the
different components of the intervention, on self-efficacy, outcome expectations, and exercise behavior among older women
post-hip fracture.Methods: Participants were randomized to one of four groups: exercise plus, exercise only, plus only (i.e., motivation), or routine
care. Data collection was done at baseline (within 22 days of fracture), 2, 6, and 12 months post-hip fracture.Results: A total of 209 women were recruited with an average age of 81.0 years (SD=6.9). The majority was White (97.1%), was widowed
(57.2%), and had a high school education (66.7%). Generalized Estimating Equations were used to perform repeated measures
analyses. No differences in trajectories of recovery were observed for self-efficacy or outcome expectations. A statistically
significant difference in the overall trajectory of time in exercise was seen (p<.001), with more time spent exercising in
all three treatment groups.Conclusions: The study demonstrated that it was possible to engage these women in a home-based exercise program and that the plus only,
exercise only, and the exercise plus groups all increased exercise.
Support for this project was provided by National Institute on Aging grants R37 AG09901, R01-AG18668, R01 AG17082, and the
Claude D. Pepper Older Americans Independence Center P60-AG12583. 相似文献
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Objective. Bone infarction (BI) of the calcaneus is an uncommon entity which has received little mention in the recent literature. In
this paper, we review the MR images of six calcanei with BI, which demonstrate a pattern of presentation that may explain
the etiology of BI at this unusual location. Design. A retrospective review was performed of the transcribed reports of the foot or ankle MR examinations at our institution.
MR images of examinations with any marrow signal abnormality were reviewed for presence of BI and its distribution. Patients. Based on MRI criteria, four patients had calcaneal BI (none biopsy proven); they ranged in age from 37 to 51 years old. Two
patients were diagnosed with systemic lupus erythematosus, one with fibrositis, and another with polymyositis. All were treated
with corticosteroids. Results. Six calcanei (in four patients) contained a region of calcaneal BI. In five of the six, the lesions were entirely or predominantly
located in the posterior half of the calcaneus. Conclusion. Two theories are proposed which may explain why BI predominantly occurs in the posterior half of the calcaneus. First, the
convergence of the recurrent intraosseous calcaneal vessels may occasionally produce the equivalent of a single dominant vessel
that is more prone to vascular accidents. Secondly, the region between the recurrent and the epiphyseal vessels may act as
a watershed zone, increasing its susceptibility to ischemia. 相似文献
26.
Zhenlin Li Emma Colucci Charles Babinet Denise Paulin 《Neuromuscular disorders : NMD》1993,3(5-6):423-427
Desmin synthesis is restricted to cardiac, skeletal and smooth muscles. In several familial myopathies involving fibre disorganization, filamentous aggregation of desmin has been characterized. During the development of the mouse embryo, desmin is one of the first muscle proteins detected in both the heart and the somites. To identify the DNA sequences involved in the regulation of desmin gene expression a 4.5 kb 5′-flanking region of the human desmin gene has been isolated. Different mutants were used to characterize specific enhancers in vitro and in vivo. The results obtained with transgenic mice provide evidence that the 1 kb cis-regulatory sequences, functional in skeletal muscle cells in vitro, confer specific developmental control for skeletal muscles. Furthermore, distinct programmes for cardiac and skeletal muscle-specific expression of the desmin gene are revealed. 相似文献
27.
HIV seroincidence among patients at clinics for sexually transmitted diseases in nine cities in the United States 总被引:1,自引:0,他引:1
Weinstock H Dale M Gwinn M Satten GA Kothe D Mei J Royalty J Linley L Fridlund C Parekh B Rawal BD Busch MP Janssen RS 《Journal of acquired immune deficiency syndromes (1999)》2002,29(5):478-483
Although the numbers of newly reported diagnoses of AIDS decreased in the 1990s, it is not clear whether they reflect a decreasing number of new HIV infections. Direct measurement of HIV incidence through follow-up cohort studies is difficult and costly. We estimated HIV incidence and trends in incidence among men who have sex with men (MSM) and heterosexual men and women at clinics for sexually transmitted diseases (STDs) by using a recently developed serologic testing algorithm that requires only a single blood specimen. Cross-sectional anonymous serosurveys were conducted at 13 STD clinics in nine cities in the United States from 1991 through 1997. Before anonymous HIV testing, demographic and clinical information was abstracted. Of 129,774 specimens tested, 362 (0.28%) were from persons estimated to be recently infected. Incidence among MSM was 7.1% (95% confidence interval (CI): 4.8-10.3), 14 times higher than that among heterosexuals, which was 0.5% (CI: 0.4- 0.7). Incidence among MSM and heterosexuals remained unchanged during the time studied. Decreasing rates of new AIDS diagnoses in the 1990s do not reflect stable rates of new HIV infections among MSM and heterosexual patients attending these clinics. 相似文献
28.
Myosin isozymes in avian skeletal muscles. I. Sequential expression of myosin isozymes in developing chicken pectoralis muscles 总被引:11,自引:0,他引:11
Susan Lowey Pamela A. Benfield Denise D. LeBlanc Guillermina S. Waller 《Journal of muscle research and cell motility》1983,4(6):695-716
Myosin has been purified from chicken pectoralis muscle at various stages of development, from 10 days' incubation to approximately 10 months after hatching. Embryonic myosin from the earliest stage showed a high level of ATPase activity, similar to that obtained for adult pectoralis myosin. Two-dimensional peptide mapping of partial chymotryptic digests showed, however, that is heavy chain is quite different from that of adult fast myosin. The immunological crossreactivity observed between embryonic myosin and adult fast (pectoralis) myosin is therefore due to shared antigenic determinants rather than the presence of any adult isoforms. In an accompanying paper we will show that embryonic myosin at 10 days' incubation is not a single species, but consists of at least two heavy chain isozymes. The minor fraction binds slow light chains preferentially, and appears to be largely responsible for the observed crossreactivity with slow (ALD) myosin. None of the embryonic myosins is equivalent to the adult forms. Prior to hatching, LC3f is present only in very small amounts (less than 5%), and the adult light chain pattern, containing LC1f and LC3f in equimolar amounts, is not generated until after one week post-hatching. At about that time a new heavy chain population is detected, different from either the embryonic heavy chain or the adult heavy chain. The adult heavy chain peptide pattern appears from about three weeks' post-hatching, but a map indistinguishable from that of adult myosin is not observed until about 26 weeks. None of the observed differences in peptide maps can be related to different strains of chicken; pectoralis myosin from adult White Rock gave an identical map to that from White Leghorn. Unexpectedly, posterior latissimus dorsi (PLD) myosin from White Leghorn appears to be different from pectoralis myosin from the same strain, despite the histochemical and immunocytochemical similarity of the two muscles. We conclude that myosin polymorphism is widespread in muscle tissue, and that the expression of myosin isozymes and their subunits is under developmental regulation. 相似文献
29.
ATP released from astrocytes during swelling activates chloride channels 总被引:19,自引:0,他引:19
Darby M Kuzmiski JB Panenka W Feighan D MacVicar BA 《Journal of neurophysiology》2003,89(4):1870-1877
ATP release from astrocytes contributes to calcium ([Ca(2+)]) wave propagation and may modulate neuronal excitability. In epithelial cells and hepatocytes, cell swelling causes ATP release, which leads to the activation of a volume-sensitive Cl(-) current (I(Cl,swell)) through an autocrine pathway involving purinergic receptors. Astrocyte swelling is counterbalanced by a regulatory volume decrease, involving efflux of metabolites and activation of I(Cl,swell) and K(+) currents. We used whole cell patch-clamp recordings in cultured astrocytes to investigate the autocrine role of ATP in the activation of I(Cl,swell) by hypo-osmotic solution (HOS). Apyrase, an ATP/ADP nucleotidase, inhibited HOS-activated I(Cl,swell), whereas ATP and the P2Y agonists, ADPbetaS and ADP, induced Cl(-) currents similar to I(Cl,swell). Neither the P2U agonist, UTP nor the P2X agonist, alpha,beta-methylene ATP, were effective. BzATP was less effective than ATP, suggesting that P2X7 receptors were not involved. P2 purinergic antagonists, suramin, RB2, and pyridoxalphosphate-6-azophenyl-2',4'-disulfonic acid (PPADS) reversibly inhibited activation of I(Cl,swell), suggesting that ATP-activated P2Y1 receptors. Thus ATP release mediates I(Cl,swell) in astrocytes through the activation of P2Y1-like receptors. The multidrug resistance protein (MRP) transport inhibitors probenicid, indomethacin, and MK-571 all potently inhibited I(Cl.swell). ATP release from astrocytes in HOS was observed directly using luciferin-luciferase and MK-571 reversibly depressed this HOS-induced ATP efflux. We conclude that ATP release via MRP and subsequent autocrine activation of purinergic receptors contributes to the activation of I(Cl,swell) in astrocytes by HOS-induced swelling. 相似文献