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71.
Cardiovascular adaptations in rats submitted to a resistance-training model   总被引:3,自引:0,他引:3  
1. The present study sought to evaluate cardiovascular adaptations, such as blood pressure (BP), heart rate (HR) and cardiac hypertrophy, to resistance training (RT) in a rat model. 2. The training protocol consisted of four sets of 10-12 repetitions of the squat exercise performed at 65-75% of one repetition maximum (1RM) over 4 weeks. Animals were randomly divided into three groups: control (n = 8, CO), electrically stimulated (n = 8, ES) and trained (n = 8, TR; also electrically stimulated). Blood pressure and HR were measured by a direct method in conscious rats after the training period. 3. All groups began with similar 1RM and 1RM/bodyweight (BW) ratio, however, at the end of the protocol only the TR group was different from the beginning (56% and 50%, respectively; both P < 0.01). The CO and ES groups had similar values for cardiac chambers weight/BW ratio, HR and diastolic, systolic and mean BP. Left ventricular hypertrophy (LVH) determined by the left ventricle (LV) weight/BW ratio was increased in the TR group (12%) when compared to CO (P < 0.01) or ES groups (P < 0.01). No changes were found in the weights of the atrium or right ventricle. Diastolic (14%) and mean BP (13%) were lower in the TR group (P < 0.05), whereas systolic BP and HR remained unchanged. 4. Collectively these results demonstrate that the rat RT model used is associated with significant development of cardiac hypertrophy and lowering of resting BP. These cardiovascular adaptations seem to a result of the training exercise and not influenced by stress since circulating catecholamine levels and adrenal gland weights remained unchanged in all groups.  相似文献   
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IgA deficiency     
OBJECTIVE: The studies about immunoglobulin A (IgA) deficiencyin the clinical, laboratorial and terapeutic aspects. METHODS: Bibliografic review of the last ten years about thesubject by Medline system and direct research. RESULTS AND CONCLUSIONS: IgA deficiency is the most frequent primary immunodeficiency, with the average prevalence of 1:700and must be studied in its clinical, laboratorial and terapeutic aspectsby pediatrician and other specialists. The clinical characteristics ofthe total and partial immunodeficiency must be known, so as thecomplications and laboratory techniques for determine accurate diagnosis and prognostic.  相似文献   
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This study analyzed the bond strength (BS) of HEMA versus HEMA-free self-etch adhesive systems to dentin. The occlusal surface of 20 third molars was removed and the dentin was abraded with 600-grit silicon carbide paper. The teeth were randomly assigned to 4 groups (n = 5) and restored with GO, Adper SE Plus, OptiBond All-In-One, and Clearfil 3S Bond adhesive systems and Filtek Z350 composite. After light curing (600 mW/cm2), the teeth were stored in distilled water at 37 oC for 24 h and were sectioned in the mesiodistal and buccolingual directions to obtain sticks (0.8 mm2). The sticks were subjected to tensile force using a universal testing machine (0.5 mm/min), and the modes of failure were analyzed by scanning electron microscopy and classified as adhesive, cohesive, or mixed. The BS data (in MPa) were treated using one-way ANOVA and Tukey's tests at 5% significance. GO presented the lowest mean bond strength value (10.57 ± 3.72) and differed significantly from the other materials (p = 0.001), which, in turn, presented statistically similar results (p>0.05) among themselves: Adper SE Plus (29.08 ± 8.93), OptiBond All-In-One (28.36 ± 6.49), and Clearfil 3S Bond (28.62 ± 6.97). Mixed fractures were the most prevalent. It was concluded that the influence of HEMA on BS to dentin was material dependent.  相似文献   
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Background

The prevalence of knee osteoarthritis(OA) in East Asia is as common for men and even higher for women than that reported in the Caucasian population. Since both population aging and economic growth have taken place at a much faster pace in Asian countries, such as South Korea, one would expect knee OA to become a major public health problem. However, few studies have examined the influence of knee OA on the quality of life (QoL) and physical function in Asia. The aim of this cross-sectional study is to investigate the influence of knee osteoarthritis (OA) on the quality of life (QoL), function and lower extremity physical performance and the gender difference in its influence in elderly community residents in Korea.

Methods

Participants were from the population-based Hallym Aging Study (HAS). The mean age of the 504 study subjects was 70.2 years and 274 (54%) were women. Demographic information was obtained by questionnaire, and radiographic evaluations consisted of weight-bearing semi-flexed knee radiographs. Self-reported QoL and function were assessed using Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index and Short Form 12-item (SF-12). Performance-based lower extremity function was assessed using the tests consisting of standing balance, usual walk and chair stands. The odds ratios(ORs) for belonging to the worst quartile of WOMAC and physical performance test were calculated by logistic regression analysis in radiographic knee OA compared to non-OA after adjustment of confounders. Scores for SF-12 items were analyzed using general linear models and means adjusted for age, BMI and OA severity were compared.

Results

Subjects with radiographic knee OA had significantly increased OR for belonging to the worst WOMAC quartile(for pain, 2.13,95% confidence interval[CI], 1.33-3.40, for stiffness, 2.94,95% CI,1.78-4.86, and for function, 2.97, 95% CI,1.83-4.81) and significantly worse SF-12 scores compared to non-OA after adjustment of age, BMI and sex. Women had worse WOMAC and SF-12 scores compared to men, regardless of the presence of radiographic knee OA after adjustment of age, BMI and OA severity. OA subjects had significantly worse performance score for usual walk and chair stands compared to non-OA subjects, but the ORs were no more significant after adjustment of sex.

Conclusions

Knee OA negatively affects the QoL and physical function in both genders, but women are more adversely affected than men.  相似文献   
78.
The objective of this study was to evaluate the existence of hemodynamic arterial flow correlation between preoperative duplex scanning (DS) and intraoperative direct outflow resistance (IDOR) measurements in ischemic lower limb revascularization. Sixty-eight ischemic lower limbs were submitted to preoperative DS. Anatomic and hemodynamic arterial characteristics of the outflow system were recorded, and the results were considered in the distal anastomosis placement site decision making. IDOR measurements were obtained at the same arterial segment, and Pearson's correlation coefficient test was performed to study the preoperative DS power in predicting the intraoperative outflow resistance. DS was technically satisfactory and helped define the distal anastomosis site in 93.2% of the cases (supragenicular popliteal artery, 19 [27.9%]; infragenicular popliteal artery, 10 [14.7%]; crural artery, 31 [57.4%]). A positive correlation could be found between preoperative DS and IDOR (0.450; p < .001). This correlation was particularly powerful in the crural artery (0.715; p < .001) when compared with the popliteal arterial segment (0.237; p = .192). Preoperative DS may help define the best distal arterial and outflow segment to be revascularized based on anatomic and hemodynamic parameters. There is a positive flow correlation between preoperative DS and IDOR that seems to be stronger in crural revascularization surgery.  相似文献   
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