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Dupont G Moalla W Matran R Berthoin S 《Medicine and science in sports and exercise》2007,39(7):1170-1176
PURPOSE: To assess the effects of the intensity of short recoveries on performance by a Wingate test and on the deoxyhemoglobin variations. METHODS: Twelve male subjects performed a graded test and three sessions of repeated all-out tests with different recovery natures. The repeated all-out tests included two sprints: a 15-s Wingate test followed by a 30-s Wingate test. The recovery between the two was 15 s in duration and was either passive, active at 20% of maximal aerobic power, or active at 40% of maximal aerobic power. Changes in deoxyhemoglobin were measured using by the near-infrared spectroscopy technique. RESULTS: Mean power (517 +/- 26 W) and peak power (1085 +/- 153 W) of the 30-s Wingate test performed after passive recovery were significantly higher (P < 0.05) than mean power and peak power performed after active recovery at 20% (484 +/- 30 and 973 +/- 112 W, respectively) and 40% of maximal aerobic power (492 +/- 35 and 928 +/- 116 W, respectively). Deoxyhemoglobin variations were significantly higher (P < 0.05) during the passive recovery (12.8 +/- 5.3 microM) than during the active recovery conditions at 20% (4.3 +/- 2.6 microM) and 40% of maximal aerobic power (3.9 +/- 2.6 microM). CONCLUSION: These results demonstrate that when two Wingate tests are performed almost successively but with a short recovery between the two, passive recovery is more appropriate than active recovery to restore the performance level. 相似文献
54.
Influence of Common and Specific HLA-DRB1/DQB1 Haplotypes on Genetic Susceptibilities of Three Distinct Arab Populations to Type 1 Diabetes
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Mouna Stayoussef Jihen Benmansour Fayza A. Al-Jenaidi Rita Nemr Muhallab E. Ali Touhami Mahjoub Wassim Y. Almawi 《Clinical and Vaccine Immunology : CVI》2009,16(1):136-138
The contribution of HLA DRB-DQB to type 1 diabetes (T1D) in Bahrainis, Lebanese, and Tunisians was investigated. DRB1*030101-DQB1*0201 was a locus that conferred susceptibility in three populations, while DRB1*040101-DQB1*0302 was a locus that conferred susceptibility only in Tunisians and Bahrainis. The DRB1*100101-DQB1*050101 (Bahrainis) and DRB1*150101-DQB1*060101 (Lebanese) loci were largely protective. The contribution of HLA to T1D must be evaluated with regard to ethnic background. 相似文献
55.
Hector M. González Miguel Ceballos Wassim Tarraf Brady T. West Mary E. Bowen William A. Vega 《American journal of public health》2009,99(10):1879-1885
Objectives. We compared risk for several medical illnesses between immigrant and US-born older Mexican Americans to determine the relationship between functional health and years of US residency among immigrants.Methods. Cross-sectional, multistage probability sample data for 3050 Mexican Americans aged 65 years or older from 5 US southwestern states were analyzed. Self-rated health, medical illnesses, and functional measures were examined in multivariate regression models that included nativity and years of US residency as key predictors.Results. Self-rated health and medical illnesses of immigrant and US-born groups did not differ significantly. Immigrants with longer US residency had significantly higher cognitive functioning scores and fewer problems with functional activities after adjustment for predisposing and medical need factors.Conclusions. Among older Mexican Americans, immigrant health advantages over their US-born counterparts were not apparent. Immigrants had better health functioning with longer US residency that may derive from greater socioeconomic resources. Our findings suggest that the negative acculturation–health relationship found among younger immigrant adults may become a positive relationship in later life.More than 30 years ago, Teller and Clyburn reported more favorable birth outcomes in Bexar County, Texas, for Spanish-surnamed residents than for non-Latino White and African American residents.1 Despite the disadvantaged economic and social position of many Latinos, additional reports appeared of unexpected favorable birth and longevity outcomes for Latinos (primarily Mexican Americans) compared with other ethnic groups.2–5 These findings were considered paradoxical, since they ran contrary to the negative socioeconomic health gradient documented in the public health literature.6,7 The Latino health paradox contends that despite experiencing disproportionate exposure to risk factors for excess morbidity and mortality associated with low socioeconomic position, Latinos, primarily Mexican American immigrants, generally have more favorable health outcomes than Mexican Americans born in the United States, most other minorities, and nonminorities.8 The longer these healthy immigrants resided in the United States and acculturated, the more likely they were to report deterioration in health status indicators compared with recent immigrants.9The mental health researchers Rogler et al. referred to “acculturation as an exogenous force shaping the conditions for the rise to psychological distress.”10(p588) This phenomenon was later coined the “acculturative stress” hypothesis and widely used in mental health research of the Latino population. However, acculturative stress models have important limitations in health research because they confound the effects of cultural change on health behaviors with pathology. In addition, they are temporally unspecific and thus inconsistent with developmental models of health. We offer an alternative, the “acculturation–health” hypothesis, to emphasize that health outcomes are instead conditional on multiple life-course contingencies that vary in importance as determinants over one''s life span. The temporal relationships between acculturation and health can range from negative to positive during the lifespan of an individual. Although the negative effects of acculturation are commonly described in the literature, positive outcomes are observed as well and also require explanations.11–15 Acculturative stress assumes a cumulative, linear, dose–response association of acculturation with health. An acculturation–health hypothesis accounts for transactions between endogenous (individual-level) and exogenous (external) factors that affect health differentially over the life course. These factors are systematically influenced by acculturation across multiple domains of life activity.The proposed acculturation–health model assumes that there are multiple points in the life course that are critical for improving health and lowering the risk of weathering effects seen in aging among minority groups.16 Carefully focused research could lead to timely and effective interventions that improve health outcomes across the life course. The assumption that a constant acculturation–health relationship is generally negative and leads to declines in health among Mexican Americans is limiting because it is overly deterministic and restricts opportunities for identifying determinants of long-range outcomes and life-course stages when they are most consequential. Although we can assume that living in a new society introduces behavioral, social, and environmental changes that may negatively influence health, there may be benefits as well, such as acquisition of new occupational skills, greater exposure to public health information, and use of preventive medicine. Nevertheless, it is unclear how these changes are expressed in the long run in the health of older Mexican Americans.Mexican Americans represent more than two-thirds of US Latinos and, perhaps accordingly, most previous studies have focused on the relationship between Mexican American acculturation (or various proxies of acculturation, such as language preference and years of US residency) and health.17 For younger Mexican Americans, most studies have reported negative relationships between acculturation and health11—for example, for birth outcomes18,19 and perinatal health behaviors,20,21 general health behaviors (e.g., nutrition and physical exercise),22 vascular disease risks (e.g., diabetes),23,24 and substance abuse and mental disorders.25,26 Several reports have shown positive associations between acculturation and higher use of preventive medical services, which may relate to the higher economic position of more acculturated and US-born Mexican Americans.27–30 Among older adults, the prevalence of depression and dementia are reportedly lower among acculturated Mexican Americans.12,13 Furthermore, there is evidence that greater social assimilation, as evidenced by English-language acquisition and more years of education, are associated with lower disability rates and higher self-esteem.14,15,31These general findings have led scientists to hypothesize that immigrants are somehow healthier than US-born Mexican Americans and non-Latino Whites and that with longer US residency, acculturation erodes immigrants'' health.9,32 The negative aspects of the acculturation–health relationship dominate current thinking about Mexican American health, especially regarding acculturation-related changes in risk behaviors such as diet, exercise, and substance abuse.33 However, if the association between acculturation and health is conditional and predicated on various endogenous and exogenous life-course factors, recent work among older adults may better inform us about the long-term acculturation–health relationship.Our first aim was to examine whether the “healthy immigrant” phenomenon persists among older Mexican Americans by comparing the rates of several medical conditions between US-born and immigrant groups. Second, we sought to determine if functional health was negatively associated with longer exposure to the host country within a representative sample of immigrant Mexican Americans. On the basis of previous work,12–14,31 we expected that the health status of US-born and immigrant older Mexican Americans would not differ. Third, we sought to examine if longer US residency would be associated with better functional health among older Mexican American immigrants. We expected that increased wealth, access to healthcare and services would facilitate or mediate better health functioning.6,34,35 Finally, in examining the health of older Mexican Americans, we aimed to compare the acculturative stress hypothesis and the acculturation–health hypothesis for a better understanding of their utility for the study of health. 相似文献
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57.
Spiess PE Pettaway CA Vakar-Lopez F Kassouf W Wang X Busby JE Do KA Davuluri R Tannir NM 《Cancer》2007,110(8):1729-1737
BACKGROUND: The current study was conducted to determine the clinical characteristics and prognostic features associated with prostatic small cell carcinoma (SCC). METHODS: Between January 1985 and May 2005, 83 patients with SCC of the prostate were identified. Univariate and multivariate Cox proportional hazards modeling were used to assess the prognostic significance of the clinical parameters associated with disease-specific outcomes. RESULTS: Twenty-one patients had no evidence of distant metastasis at the time of the diagnosis of SCC, with the remaining patients demonstrating radiologic or biopsy-proven evidence of metastatic disease. Compared with patients with metastases, patients without metastases at the time of diagnosis were older (P = .001) and had a lower serum lactate dehydrogenase (LDH) level at the time of diagnosis (P = .002). On multivariate analysis, an elevated serum LDH level and low serum albumin at the time of SCC diagnosis was found to be predictive of inferior progression-free survival (P = .02 and P = .008, respectively) and inferior disease-specific survival (DSS) (P = .02 and P = .01, respectively). At the time of last follow-up, 72 patients (87%) had died of disease, with a median DSS duration of 13.1 months (range, 10.7-17.1 months). There was a statistically significant difference noted with regard to the median DSS of patients with nonmetastatic versus those with metastatic SCC (17.7 months [95% confidence interval (95% CI), 12.1-39.2 months] vs 12.5 months [95% CI, 8.1-16.1 months], respectively; P = .03). CONCLUSIONS: SCC of the prostate is a highly aggressive tumor, with serum LDH and albumin levels at the time of diagnosis believed to be predictive of disease-related outcomes. Although palliative, current systemic therapy does not result in cure and does not provide long-term survival for patients with metastases. For patients with nonmetastatic disease, a strategy utilizing systemic and local therapies should be evaluated further. 相似文献
58.
Yoram Halevi Dennis S. Bernstein Wassim M. Haddad 《Optimal control applications & methods.》1991,12(3):163-172
The problem of deriving a suboptimal LQG controller which is internally stable is considered. In the case where the controller is internally unstable a procedure is given for modifying the optimization parameters, i.e. the state weighting matrix and/or the process noise intensity. Sufficient conditions for controller stability of appropriately modified optimization problems are given for both the full-order and reduced-order cases. A final tuning procedure is then used to minimize the deviation from the original LQG problem. 相似文献
59.
Berger MM Binnert C Chiolero RL Taylor W Raffoul W Cayeux MC Benathan M Shenkin A Tappy L 《The American journal of clinical nutrition》2007,85(5):1301-1306
BACKGROUND: After major burns, patients exhibit an intense catabolism, and the wounds require surgery and grafting for closure. Complications, such as weight loss and delayed wound healing, are worsened by trace element (TE) deficiencies. OBJECTIVE: We aimed to assess the effects of TE supplements on systemic substrate turnover and local protein metabolism during wound healing after major burns. DESIGN: This was a prospective, randomized, placebo-controlled trial in 21 patients aged 35 +/- 11 y with burns on 45 +/- 16% of their body surface area; 12 had skin biopsies performed on days 3, 10, and 20, and 10 patients underwent a stable-isotope investigation on day 10. Intravenous copper, selenium, and zinc (TE group) or vehicle (V group) was given with a saline solution for 14-21 d. On day 10, [(13)C]phenylalanine (600-microg/kg bolus followed by 12 microg x kg(-1) x min(-1)) plus 6-[(2)H(2)]glucose and [(2)H(5)]glycerol were infused for 6 h to determine skin protein turnover. Biopsies were performed 1 and 6 h after the start of infusion to determine [(13)C]phenylalanine enrichment. RESULTS: The patients' mean age and burn severity did not differ significantly between the groups nor between the skin investigations subgroups. Plasma TE concentrations were significantly higher in the TE group. In the burned areas, the skin contents of selenium (P=0.02) and zinc (P=0.03) increased by day 20. The supernatant-to-plasma (13)C enrichment ratio in burned skin was 0.363 +/- 0.094 (TE group) and 0.286 +/- 0.130 (V group) after 1 h (NS) and 0.592 +/- 0.153 (TE group) and 0.262 +/- 0.171 (V group) after 6 h, which reflected lower catabolism in the TE group (P=0.03). No significant differences in whole-body substrate turnover were found between the groups. CONCLUSION: TE supplementation was associated with an increased skin tissue content of selenium and zinc and with a reduction in skin protein catabolism. 相似文献
60.
BACKGROUND: It's generally agreed that calcified liver cystic Echinococcosis (CE) is associated with negative serology; the influence of other cystic features on serologic result remains unclear. The aim of this study is to determine predictive factors of negative indirect passive hemagglutination (IHA) in liver CE. METHODS: 119 patients operated on for liver CE, had preoperative IHA. Correlation was studied between serological result and sex, age of patient and number (single vs multiple), size, ultrasonic type (unilocular, multivesicular, degenerative) and intrabiliary rupture of cyst. RESULTS: IHA sensitivity was 74.8%. Univaried analysis showed that false negative serology was correlated with age <10 or >20 years (p < 0.01), single cyst (p < 0.006), cystic size <9 cm (p < 0.03) and unilocular or degenerative cyst in comparison with multivesicular type (p < 0.01 and p < 0.03 respectively). IN CONCLUSION: in liver CE, cystic predictive factors of false negative IHA are single cyst, unilocular or degenerative type and size inferior to 9 cm. 相似文献