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91.
Background: Strength training post stroke is widely acknowledged as an important part of a rehabilitation program. Muscle strength has been shown to be a significant contributor to physical disability after stroke, which in turn has an immense impact on the reintegration of patients into society, affecting their quality of life.

Objective: This was a randomized intervention trial to determine the effect of a resistance training program on the quality of life in patients with stroke.

Methods: An experimental group (EG), consisting of 11 subjects aged 51.7 ± 8.0 years, and a control group (CG), consisting of 13 subjects aged 52.5 ± 7.7 years, were studied before and after 12 weeks. EG underwent 12 weeks of strength training three times a week. The CG did not undergo strength training during the 12-week study period.

Results: There was a significant increase in quality of life from pre-test to post-test (Δ% = 21.47%; p = 0.021) in EG. There were significant differences in all indicators of quality of life between groups at 12 weeks. There were greater gains in strength in EG than in CG (p ≤ 0.05). There was a negative correlation between the strength gains as determined with the 1RM test and the quality of life, especially in lower limb exercises.

Conclusion: The results of this study indicate that there was an improvement in the measures of strength in EG, and that there was a correlation between improvements in strength and quality of life in these patients who had previously suffered a stroke at least one year prior to study.  相似文献   
92.
It has recently been shown that the acinus can have a reduced efficiency due to a “screening effect” governed by the ratio of oxygen diffusivity to membrane permeability, the gas flow velocity, as well as the size and configuration of the acinus. We present here a top to bottom calculation of the functioning of a machine acinus at exercise that takes this screening effect into account. It shows that, given the geometry and the breathing dynamics of real acini, respiration can be correlated to a single equivalent parameter that we call the integrative permeability. In particular we find that both V˙O2,max and PAO2 depend on this permeability in a non-linear manner. Numerical solutions of dynamic convection–diffusion equations indicate that only a narrow range of permeability values is compatible with the experimental measurements of PAO2 and V˙O2,max. These permeability values are significantly smaller than those found in the literature. In a second step, we present a new type of evaluation of the diffusive permeability, yielding values compatible with the top to bottom approach, but smaller than the usual morphometric value.  相似文献   
93.
The acute phase response refers to a nonspecific and complex systemic reaction of the organism that occurs shortly after any tissue injury. The acute phase response is considered a part of the innate host defense system, which is responsible for the survival of the host during the critical early stages of attack, and in evolutionary terms, it precedes the acquired immune response. The purpose of this study was to determine serum protein concentrations, including the acute phase protein profile in agoutis (Dasyprocta azarae) in captivity, by means of sodium dodecyl sulfate polyacrylamide gel electrophoresis. Blood samples from 11 adult healthy animals (nine females and two males) were obtained. The serum proteinogram had 21 proteins with molecular weights ranging from 15 to 240 kD. The acute phase proteins identified were: ceruloplasmin, transferrin, albumin, haptoglobin, α-1-acid glycoprotein, and hemoglobin. IgA, IgG heavy and light chains, and nonnominal identified proteins of 240, 210, 140, 98, 78, 48, 35, 31, 23, and 15 kD were also identified. The determination of the acute phase protein concentrations is a useful method for the early detection of subclinical disease or changes in the healthy animal, with predictive information on the development of disease in the future. It is possible to standardize the reference values of the serum protein profile of agoutis, which can be used for diagnosis and prognosis, treatment and clinical follow-up of nutritional disorders, and immune-mediated inflammatory diseases that may affect these animals.  相似文献   
94.

Introduction

During root formation, Smad-4 plays a key role during the epithelial–mesenchymal interactions and the Hertwig's epithelial root sheath (HERS) apical proliferation. The root formation and eruption of rat molars is impeded by alendronate treatment due to the inhibition of bone resortion by this drug. The present study aimed to examine the structures affected in the developing root and immunodetect the presence of Smad-4 in rats treated with alendronate.

Methods

Newborn Wistar rats were daily injected 2.5 mg/kg alendronate (ALN) during 9, 12 and 30 days. The controls (CON) were injected with saline. The maxillae were fixed and embedded in paraffin or Spurr resin. Paraffin sections were incubated in Smad-4 antibody that was labelled with DAB. The ultrathin sections were examined in a transmission electron microscope.

Results

In ALN, a short portion of root dentine was formed; the epithelial diaphragm (ED) and the dental follicle (DF) were disorganized by the contact of bone trabeculae. The (CON) molar roots developed normally. Smad-4 labelling was detected in the cytoplasm of fibroblasts and cementoblasts adjacent to the cementum in CON; in ALN group, few ED cells presented weak immunolabelling. Ultrastructurally, the ED and DF appeared disrupted due to the presence of thin bone trabeculae between its cells. It resulted in the lack of apical proliferation of HERS and, consequently, arrest of root formation.

Conclusion

The immunodetection of Smad-4 in the DF cells of ALN specimens indicates that the signalling for the differentiation of these cells into cementum-forming fibroblasts and cementoblasts occurs, despite the impairment of root elongation.  相似文献   
95.
Background and Objective: A low‐grade systemic inflammatory status originating from periodontal infection has been proposed to explain the association between periodontal disease and systemic conditions, including adverse obstetric outcomes. The aim of this study was to evaluate the effect of periodontal therapy during pregnancy on the gingival crevicular fluid and serum levels of six cytokines associated with periodontal disease and preterm birth. Material and Methods: A subsample of 60 women (18–35 years of age) up to 20 gestational weeks, previously enrolled in a larger randomized clinical trial, was recruited for the present study. Participants were randomly allocated to receive either comprehensive nonsurgical periodontal therapy before 24 gestational weeks (n = 30, test group) or only one appointment for supragingival calculus removal (n = 30, control group). Clinical data, and samples of blood and gingival crevicular fluid, were collected at baseline, at 26–28 gestational weeks and 30 d after delivery. The levels of interleukin (IL)‐1β, IL‐6, IL‐8, IL‐10, IL‐12p70 and tumor necrosis factor‐α were analyzed by flow cytometry. Results: After treatment, a major reduction in periodontal inflammation was observed in the test group, with bleeding on probing decreasing from 49.62% of sites to 11.66% of sites (p < 0.001). Periodontal therapy significantly reduced the levels of IL‐1β and IL‐8 in gingival crevicular fluid (p < 0.001). However, no significant effect of therapy was observed on serum cytokine levels. After delivery, the levels of IL‐1β in the gingival crevicular fluid of the test group were significantly lower than were those in the control group (p < 0.001), but there were no significant differences between test and control groups regarding serum cytokine levels. Conclusion: Although periodontal therapy during pregnancy successfully reduced periodontal inflammation and gingival crevicular fluid cytokine levels, it did not have a significant impact on serum biomarkers.  相似文献   
96.
97.
Abstract. Thomas J‐A II, Gerber L, Moreira DM, Hamilton RJ, Bañez LL, Castro‐Santamaria R, Andriole GL, Isaacs WB, Xu J, Freedland SJ (Durham VA Medical Center, Durham, NC, USA; Duke University School of Medicine, Durham, NC, USA; The Author Smith Institute for Urology, New Hyde Park, NY, USA; Memorial Sloan‐Kettering Cancer Center, New York, NY, USA; GlaxoSmithKline, Research Triangle Park, NC, USA; Washington University School of Medicine, St. Louis, MO, USA; Johns Hopkins Hospital, Baltimore, MD, USA; Wake Forest University, Winston‐Salem, NC, USA; and Duke University School of Medicine, Durham, NC, USA). Prostate cancer risk in men with prostate and breast cancer family history: results from the REDUCE study (R1). J Intern Med 2012; 272 : 85–92. Background. To what degree the associations between PCa risk and family history of prostate cancer (PCa) and/or breast cancer (BCa) are attributable to screening biases is unclear. We examined these questions within the REDUCE study, where biopsies were largely independent of prostate specific antigen (PSA) minimizing screening biases. Methods. Data were from REDUCE, which tested dutasteride 0.5 mg daily for PCa risk reduction in men with PSA 2.5–10.0 ng mL?1 and a negative prestudy biopsy. Among men undergoing at least one on‐study biopsy with complete data (n = 6415; 78.1%), the association between family history and PCa risk was tested using multivariate logistic regression adjusting for clinicodemographic characteristics. Results. A family history of PCa alone was associated with increased PCa diagnosis (OR: 1.47, 95%CI: 1.22–1.77). In North America, PCa family history was not related to PCa diagnosis (OR: 1.02, 95%CI: 0.73–1.44), whereas outside North America, PCa family history was significantly related to diagnosis (OR: 1.72, 95%CI: 1.38–2.15) (P‐interaction = 0.01). A family history of both PCa and BCa (OR: 2.54, 95%CI: 1.72–3.75) but not BCa alone (OR: 1.04, 95%CI: 0.84–1.29) was associated with increased PCa risk versus no family history and irrespective of geographical region. Conclusions. In REDUCE, PCa family history was significantly related to PCa diagnosis, although only for men outside North America. The presence of both PCa and BCa family history significantly increased risk versus PCa family history alone, irrespective of geographical region. Ultimately, our observations may support the need for changes in how we address family history in terms of both risk of PCa diagnosis and general risk stratification.  相似文献   
98.
99.
100.
Formation of metastases in the lungs is the major cause of death in patients suffering from osteosarcoma (OS). Metastases at presentation and poor response to preoperative chemotherapy are strong predictors for poor patient outcome. The elucidation of molecular markers that promote metastasis formation and/or chemoresistance is therefore of importance. CD44 is a plasma membrane glycoprotein that binds to the extracellular matrix component hyaluronan (HA) and has been shown to be involved in metastasis formation in a variety of other tumors. Here we investigated the role of CD44 expression on OS tumor formation and metastasis. High CD44 expression, evaluated with a tissue microarray including samples from 53 OS patients and stained with a pan‐CD44 antibody (Hermes3), showed a tendency (p < 0.08) to shortened overall survival. However, nonresponders and patients with lung metastases and high CD44 expression had significantly poorer prognosis than patients with low CD44 expression. Overexpression of the standard CD44 isoform (CD44s) and its HA‐binding defective mutant R41A in osteoblastic SaOS‐2 cells resulted in HA‐independent higher migration rates and increased chemoresistance, partially dependent on HA. In an orthotopic mouse model of OS, overexpression of CD44s in SaOS‐2 cells resulted in an HA‐dependent increased primary tumor formation and increased numbers of micrometastases and macrometastases in the lungs. In conclusion, although CD44 failed to be an independent predictor for patient outcome in this limited cohort of OS patients, increased CD44 expression was associated with even worse survival in patients with chemoresistance and with lung metastases. CD44‐associated chemoresistance was also observed in vitro, and increased formation of lung metastases was found in vivo in SCID mice. © 2013 American Society for Bone and Mineral Research.  相似文献   
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