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61.
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   
62.
Older age, prior transplantation, pulmonary hypertension, and mechanical support are commonly seen in current potential cardiac transplant recipients. Transplants in 436 consecutive adult patients from 1994 to 1999 were reviewed. There were 251 using standard donors in 243 patients (age range 18-69 years). To emphasize recipient risk, 185 patients who received a nonstandard donor were excluded from analysis. The indications for transplant were ischemic heart disease (n = 123, 47%), dilated cardiomyopathy (n = 82, 32%), and others (n=56, 21%). One hundred and forty-nine (57%) recipients were listed as status I; 5 and 6% were supported with an intra-aortic balloon and an assist device, respectively. The 30-d survival and survival to discharge were 94.7 and 92.7%, respectively; 1-year survival was 89.1%. Causes of early death were graft failure (n = 6), infection (n = 4), stroke (n = 4), multiorgan failure (n = 3) and rejection (n = 2). Predictors were balloon pump use alone (OR= 11.4, p =0.002), pulmonary vascular resistance > 4 Wood units (OR = 5.7, p = 0.007), pretransplant creatinine > 2.0 mg/dL (OR = 6.9, p = 0.004) and female donor (OR = 8.3, p = 0.002). Recipient age and previous surgery did not affect short-term survival. Heart transplantation in the current era consistently offers excellent early and 1-year survival for well-selected recipients receiving standard donors. Early mortality tends to reflect graft failure while hospital mortality may be more indicative of recipient selection.  相似文献   
63.
Two outstanding features of the flowering plant family Winteraceae are the occlusion of their stomatal pores by cutin plugs and the absence of water-conducting xylem vessels. An adaptive relationship between these two unusual features has been suggested whereby stomatal plugs restrict gas exchange to compensate for the presumed poor conductivity of their vesselless wood. This hypothesized connection fueled evolutionary arguments that the vesselless condition is ancestral in angiosperms. Here we show that in Drimys winteri, a tree common to wet forests, these stomatal occlusions pose only a small fixed resistance to water loss. In addition, they modify the humidity response of guard cells such that under high evaporative demand, leaves with plugs lose water at a faster rate than leaves from which the plugs have been experimentally removed. Instead of being adaptations for drought, we present evidence that these cuticular structures function to maintain photosynthetic activity under conditions of excess water on the leaf surface. Stomatal plugs decrease leaf wettability by preventing the formation of a continuous water film that would impede diffusion of CO2 into the leaf. Misting of leaves had no effect on photosynthetic rate of leaves with plugs, but resulted in a marked decrease (≈40%) in leaves from which the plugs had been removed. These findings do not support a functional association between stomatal plugs and hydraulic competence and provide a new perspective on debates surrounding the evolution of vessels in angiosperms.  相似文献   
64.
In order to evaluate the role played by vasopressin on pressor responses elicited by stimulation of the periaqueductal gray (PAG) area by excitatory amino acids we carried out in vivo studies in genetically vasopressin deficient rats (Brattleboro). Microinjections of l-glutamic acid (glutamate, 0.6 to 60 nmol/rat) or N-methyl-d-aspartic acid (NMDA, 0.07 to 7 nmol/rat) into the PAG area of freely moving Brattleboro rats induced increases of arterial blood pressure values significantly lower than those obtained in Long Evans rats (control) (glutamate in Brattleboro rats: from +2±1 mmHg to 16±3 mmHg; glutamate in Long Evans rats: from +16±2 mmHg to +36±4 mmHg; NMDA in Brattleboro rats: from +5±2 mmHg to +34 ±8 mmHg; NMDA in Long Evans rats: from +18±7 mmHg to 80±9 mmHg; n=5). Similarly, in anaesthetized Brattleboro rats (urethane 1.2 g/kg i.p.) pressor responses to NMDA microinjections (0.7 nmol/rat) into the PAG area were significantly lower than in Long Evans rats (controls) (+15±3 mmHg vs +24±4 mmHg). In Long Evans rats NMDA injection also reversed blood pressure decrease induced by ganglionic blocker, hexamethonium and/or losartan (3 mg/kg i.v.), an AT1 receptor antagonist. In Brattleboro rats, NMDA injection did not reverse blood pressure decreases induced by hexamethonium (5 mg/kg i.v.). Moreover, hexamethonium induced blood pressure decrease was not reversed by acetylcholine injection (137 nmol/rat) into the PAG area of anaesthetized Long Evans rats, but if injected before hexamethonium, acetylcholine was able to increase blood pressure (+25±3 mmHg). Our results document: i) the importance of the PAG area in the control of cardiovascular system; ii) the involvement of excitatory amino acids in the neural control of vasopressin release; iii) the close relationship between glutamate and vasopressin in the central blood pressure regulation. Received: 1 April 1997 / Accepted: 2 February 1998  相似文献   
65.
Transglutaminase (TGase) activity was reduced in intact mitogen-stimulated human peripheral blood lymphocytes (PBL) when compared to intact resting PBL. Moreover, a treatment of the same quiescent immunocompetent cells with purified liver TGase and Ca2+ completely suppressed the mitogen-induced blast transformation. A decrease in TGase activity in neoplastically transformed seminal vesicle epithelial cells with respect to their normal parent counterpart was also observed. Our data support the notion of a possible implication of TGase in cell proliferation and transformation.  相似文献   
66.
Summary An epidemiological survey of hereditary ataxias and paraplegias was conducted in Molise, a region of Italy (335, 211 inhabitants on 1 January 1989). Total prevalence was 7.5 x 10–5 inhabitants (95% confidence limits 4.8–11.1). There were 7 patients with Friedreich's disease, 5 with early onset cerebellar ataxia with retained tendon reflexes, 4 with ataxia-telangiectasia, 9 with hereditary spastic paraplegias (2 autosomal dominant and 7 autosomal recessive cases). There was no patient with autosomal dominant cerebellar ataxia.  相似文献   
67.
The majority of hepatitis C virus (HCV)-infected individuals fail to resolve the infection and become chronically infected despite the presence of HCV-specific CTL responses directed to different HCV-derived peptide antigens. Only a minority of individuals is able to clear the virus by mounting efficient CTL responses early after acute infection, but at present it is not clear whether viral clearance is associated with CTL responses of defined specificity. To elucidate those responses associated with improvement of the disease, we analyzed CTL responses to 16 different HLA-A2-presented, HCV-derived epitopes in 12 chronically infected patients, 14 chronically infected patients treated with interferon-alpha, and in one patient with acute symptomatic disease. We show here that the majority of chronically infected individuals present CTL responses directed to an NS4-derived peptide antigen (amino acids 1789-1797). Treated patients presented stronger HCV-specific CTL responses and therapy-induced changes in CTL target choice. In particular, 13 out of 14 individuals responded to an NS3-derived epitope (amino acids 1073-1081). By longitudinal analysis we show that five individuals responding to IFN-alpha therapy with decreases in alanine aminotransferase levels presented a strong CTL activity directed to the NS3-derived epitope. One patient that spontaneously resolved the infection presented a generally strong CTL activity specific for HCV-derived epitopes with a dominant response to the NS3-derived peptide antigen. This suggests that CTL responses directed to this NS3-derived antigen may be beneficial for the control of HCV infection. Improvement of these responses may represent a therapeutic intervention in chronic HCV infection.  相似文献   
68.
69.
Nuclear translocation of β-catenin has been correlated with epidermal growth factor receptor (EGFR) overexpression/activation in nonsmall cell lung cancer. Less is known on β-catenin transactivation in high-grade pulmonary neuroendocrine tumors and on the status of β-catenin activating EGFR and human epidermal growth factor receptor 2 (HER-2) or β-catenin target genes cyclin D1 and matrix metalloproteinase-7 (MMP-7). β-catenin immunoreactivity was evaluated in 51 large-cell neuroendocrine carcinomas (LCNEC) and 45 small-cell lung carcinomas (SCLC). Nineteen cases were assessed for β-catenin gene exon 3 mutations, expression of MMP-7, and expression/gene amplification of EGFR, HER-2, and cyclin D1. β-catenin was expressed in all 96 high-grade neuroendocrine tumors, the vast majority (94%) showing >50% immunopositive cells. A disarrayed immunoreactivity, however, was commonly encountered consisting in variably altered membrane-associated patterns of staining along with progressive accumulation of cytoplasmic immunoreactivity. In LCNEC, but not in SCLC, the disarrayed patterns correlated with EGFR and HER-2 protein expression. β-catenin nuclear accumulation was found in nine tumors, including seven LCNEC and two SCLC, and was always associated with disarrayed immunoreactivity and increased MMP-7, but not cyclin D1 expression. These cases, however, did not show β-catenin gene mutations or EGFR and HER-2 gene amplification or expression. No association was found between nuclear β-catenin and any clinicopathological variable including patients' survival. The subcellular compartmentalization of β-catenin is profoundly altered in high-grade pulmonary neuroendocrine tumors. A minor subset of these tumors shows β-catenin nuclear accumulation in association with increased expression of MMP-7, but not of cyclin D1, independent of EGFR and HER-2 gene amplification or expression. The authors have no significant financial or other relationship with the manufacturers of any commercial products or commercial services presented in this paper  相似文献   
70.
Objectives: To assess the efficacy and tolerability of a new matrix patch delivering 0.05 mg estradiol per day (Estraderm MX 50) in postmenopausal women with moderate to severe postmenopausal symptoms. Methods: A multicenter, double-blin, randomized, between-patient, placebo controlled trial in 109 postmenopausal women was carried out. Patches were applied twice weekly for 12 weeks. Patients were assessed at 4, 8 and 12 weeks of treatment. The primary efficacy variable was change from baseline in mean number of moderate to severe hot flushes (including night sweats) per 24 h during the last 2 weeks of treatment. Other variables included Kupperman Index, local and systemic tolerability. Plasma concentrations of estradiol (E2), estrone (E1) and estrone sulfate (E1S) were determined before and after treatment. Results: Estraderm MX was significantly superior to placebo (P < 0.001) in reducing mean number of moderate to severe hot flushes (including night sweats) per 24 h after 4, 8 and 12 weeks of treatment. The estimate of treatment group differences after 12 weeks was 4.2 hot flushes (95% confidence interval: 2.6–5.5). Estraderm MX also significantly reduced Kupperman Index at all time points compared to placebo (P < 0.001). Estraderm MX induced increases in mean E2, E1 and E1S plasma levels as expected (E2: baseline 2.7 pg/ml, 12 weeks 38.9 pg/ml; E1: baseline 18.8 pg/ml, 12 weeks 41.6 pg/ml; E1S: baseline 235.6 pg/ml, 12 weeks 765.1 pg/ml). Overall rates of adverse experiences were similar for Estraderm MX and placebo. The number of patients reporting skin irritation was low and similar in both groups. Conclusions: Estraderm MX 50, a new matrix patch, offers an effective and well tolerated dosage form for transdermal delivery of 0.05 mg E2 per day.  相似文献   
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