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81.
[Purpose] The aim of this study was to observe the effect of self-selected intensity or imposed intensity during aerobic training on perceptual and affective responses in obese women. [Subjects] The study included 26 obese women aged 30–60 years. [Methods] The subjects were randomly divided into two groups, with 13 subjects in each group: self-selected intensity and imposed intensity (10% above ventilatory threshold) groups. All subjects completed an intervention program that lasted 12 weeks, with three exercise sessions a week. The rating of perceived exertion and affective responses (Feeling Scale and Felt Arousal Scale) were monitored in the first, sixth, and twelfth weeks. [Results] Significant differences were observed between groups in heart rate and rating of perceived exertion. The affective responses during exercise were more negative in the imposed intensity group. [Conclusion] Use of a self-selected exercise intensity can promote smaller negative affective responses during exercise and provide a sufficient stimulus for improvement in cardiorespiratory fitness.Key words: Self-selected exercise, Rating of perceived exertion, Affective responses  相似文献   
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A malaria risk analysis in an irrigated area in Sri Lanka   总被引:4,自引:0,他引:4  
Malaria in Sri Lanka is unstable and epidemic, with large spatial and temporal differences in transmission dynamics. The disease is of great public health significance and identification of underlying risk factors is important in order to use the limited resources in a cost-effective way. The International Water Management Institute (IWMI) recently launched a project of GIS-based malaria risk mapping in Sri Lanka, to investigate whether this tool could be used for epidemic forecasting and for the planning of malaria control activities. This paper presents results for the Uda Walawe region in southern Sri Lanka, an irrigated agricultural area where malaria cases were mapped at the smallest administrative level for each month over a 10-year period. Malaria incidence rates were related to land- and water-use patterns, socio-economic features, and data on malaria control interventions in a multivariate analysis. Areas of high malaria risk were characterized by: (i) higher than average rainfall, (ii) greater forest coverage; (iii) slash and burn cultivation as a predominant agricultural activity; (iv) presence of many abandoned irrigation reservoirs; and (v) poor socio-economic status. Irrigated rice cultivation areas had a lower risk of malaria than non-irrigated areas. This difference could be due to socio-economic factors related to irrigation development and/or transmission dynamics related to vector density or species composition. Our findings call for malaria control strategies that are readily adapted to different ecological and epidemiological settings. Malaria risk maps are a convenient tool for discussing targeted and cost-effective interventions with disease control personnel.  相似文献   
84.
Hydroxyl radicals (OH) are involved in the development of reperfusion injury and myocardial failure. In the acute phase of the OH-mediated diastolic dysfunction, increased intracellular Ca(2+) levels and alterations of myofilaments may play a role, but the relative contribution of these systems to myocardial dysfunction is unknown. Intact contracting cardiac trabeculae from rabbits were exposed to OH, resulting in an increase in diastolic force (F(dia)) by 540%. Skinned fiber experiments revealed that OH-exposed preparations were sensitized for Ca(2+) (EC(50): 3.27+/-0.24 x 10(-6) versus 2.69+/-0.15 x 10(-6) mol/L; P<0.05), whereas maximal force development was unaltered. Western blots showed a proteolytic degradation of troponin T (TnT) with intact troponin I (TnI). Blocking of calpain I by MDL-28.170 inhibited both TnT-proteolysis and Ca(2+) sensitization, but failed to prevent the acute diastolic dysfunction in the intact preparation. The OH-induced diastolic dysfunction was similar in preparations with intact (540+/-93%) and pharmacologically blocked sarcoplasmic reticulum (539+/-77%), and was also similar in presence of the L-type Ca(2+)-channel antagonist verapamil. In sharp contrast, inhibition of the reverse-mode sodium-calcium exchange by KB-R7943 preserved diastolic function completely. Additional experiments were performed in rat myocardium; the rise in diastolic force was comparable to rabbit myocardium, but Ca(2+) sensitivity was unchanged and maximal force development was reduced. This was associated with a degradation of TnI, but not TnT. Electron microscopic analysis revealed that OH did not cause irreversible membrane damage. We conclude that OH-induced acute diastolic dysfunction is caused by Ca(2+) influx via reverse mode of the sodium-calcium exchanger. Degradation of troponins appears to be species-dependent but does not contribute to the acute diastolic dysfunction.  相似文献   
85.
Medullary thyroid cancer (MTC) shares biochemical features with other neuroendocrine tumors but the particular characteristics are largely unexplored. We investigated the biochemical neuroendocrine profile of MTC and whether specific markers could be useful in follow-up. In addition to the standard tumor marker calcitonin, plasma carcino-embryonic antigen (CEA), plasma catecholamines, (platelet) serotonin, chromogranin A, tryptase, and urinary markers of catecholamine, histamine, and serotonin metabolism were prospectively determined in 46 patients with histologically proven MTC. Patients were divided according to the stage of disease: group 1, no evidence; group 2, stable disease (SD); and group 3, progressive disease (PD). Plasma dopamine was increased in the majority of the patients with SD and PD; however it did not correlate with extent of disease. Elevated plasma platelet levels of serotonin were only present in patients with multiple endocrine neoplasia 2 with SD or PD but did not differ between those groups. Histamine metabolites were elevated in 20% of patients with SD and PD. In addition to plasma calcitonin, only CEA and chromogranin A could differentiate between stable and progressive MTC. MTCs are capable of synthesizing catecholamines, serotonin, and histamine metabolites underscoring that MTCs have metabolic characteristics in common with other neuroendocrine tumors. Thus far, clinical usefulness and relevance seems limited. The most useful markers in the follow-up of MTC are plasma calcitonin and CEA.  相似文献   
86.

Background

Prevalence of hydatidiform mole is not clearly defined, partly because most studies have reported different prevalence rates from different regions. However, there is no previous study that has determined the prevalence and associated risk factors of HM among patients with incomplete abortion evacuated at Bugando Medical Centre (BMC) and Sekou Toure Regional Hospital (STRH).

Methods

A total of 180 patients with incomplete abortion were enrolled between February 2013 and April 2013. The products of conception were collected and analyzed using Haemotoxylin and Eosin staining technique for hydatidiform moles.

Results

One hundred and eighty patients with incomplete abortion scheduled for uterine evacuation agreed to participate in this study. The overall prevalence of HM was 12.8%. Majority of patients (27.5%) with HM were those aged below 20 years. No significant association was observed with risk factors such as parity, contraceptive use, previous abortion and blood group.

Conclusion

The prevalence of HM (12.8%) was high and age between 15–20 years was the only significant associated risk factor with the presence of HM among patients with incomplete abortion. Therefore, we recommend submission of evacuated products of conception for histopathological analysis to minimize missed opportunity.  相似文献   
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88.
In order to understand the three-dimensional structure of the functional kinetochore in vertebrates, we require a complete list and stoichiometry for the protein components of the kinetochore, which can be provided by genetic and proteomic experiments. We also need to know how the chromatin-containing CENP-A, which makes up the structural foundation for the kinetochore, is folded, and how much of that DNA is involved in assembling the kinetochore. In this MS, we demonstrate that functioning metaphase kinetochores in chicken DT40 cells contain roughly 50 kb of DNA, an amount that corresponds extremely closely to the length of chromosomal DNA associated with CENP-A in ChIP-seq experiments. Thus, during kinetochore assembly, CENP-A chromatin is compacted into the inner kinetochore plate without including significant amounts of flanking pericentromeric heterochromatin.  相似文献   
89.
AIM: To determine the dose-related effects of a novel probiotic combination, I.31, on irritable bowel syndrome (IBS)-related quality of life (IBS-QoL).METHODS: A multicenter, randomized, double-blind, placebo-controlled intervention clinical trial with three parallel arms was designed. A total of 84 patients (53 female, 31 male; age range 20-70 years) with IBS and diarrhea according to Rome-III criteria were randomly allocated to receive one capsule a day for 6 wk containing: (1) I.31 high dose (n = 28); (2) I.31 low dose (n = 27); and (3) placebo (n = 29). At baseline, and 3 and 6 wk of treatment, patients filled the IBSQoL, Visceral Sensitivity Index (VSI), and global symptom relief questionnaires.RESULTS: During treatment, IBS-QoL increased in all groups, but this increment was significantly larger in patients treated with I.31 than in those receiving placebo (P = 0.008). After 6 wk of treatment, IBS-QoL increased by 18 ± 3 and 22 ± 4 points in the high and the low dose groups, respectively (P = 0.041 and P = 0.023 vs placebo), but only 9 ± 3 in the placebo group. Gut-specific anxiety, as measured with VSI, also showed a significantly greater improvement after 6 wk of treatment in patients treated with probiotics (by 10 ± 2 and 14 ± 2 points, high and low dose respectively, P < 0.05 for both vs 7 ± 1 score increment in placebo). Symptom relief showed no significant changes between groups. No adverse drug reactions were reported following the consumption of probiotic or placebo capsules.CONCLUSION: A new combination of three different probiotic bacteria was superior to placebo in improving IBS-related quality of life in patients with IBS and diarrhea.  相似文献   
90.
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