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Objective: To mechanically test the intact cardiac structure to determine the sequence of contraction within the myocardial mass to try to explain ejection and suction. Methods: In 24 pigs (30–85 kg), segment shortening at the site of sonomicrometer crystals was continuously recorded. The ECG evaluated rhythm, and Millar pressure transducers measured intraventricular pressure and dP/dt. Results: Study of segment shortening defined a sequence of contraction within the myocardial mass, starting at the free wall of the right ventricle and on the endocardial side of the antero-septal wall of the left. Crystal location defined underlying contractile trajectory; transverse in right ventricle followed by basal posterior left ventricle, and from the endocardial anterior wall to the posterior apical segment and finally to the epicardial side of the anterior wall. Mean shortening fraction averaged 18±3%, with endocardial exceeding epicardial shortening by 5±1%. Epicardial segment crystal displacement followed endocardial shortening by 82±23 ms in the anterior wall, and finished 92±33 ms after endocardial shortening stopped, time frame that matches the interval of fast drop of ventricular pressure and the start of suction. Conclusions: Crystal shortening fraction sequence followed the rope-like myocardial band model to contradict traditional thinking, with two starting points of excitation–contraction, the right anterior free wall of the right ventricle, and the endocardial side of the anterior wall. Active suction may be due to active shortening of the epicardial fibers of the anterior wall, because relaxation was not detected when both mitral and aortic valves were closed during the interval previously termed ‘isovolumetric relaxation’.  相似文献   
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Endovenous laser therapy (EVLT) for greater saphenous vein (GSV) insufficiency is a relatively new method of treatment only recently made available in Iran. This is the first long-term randomized trial comparing EVLT with high ligation of saphenous vein (HLS) in the Iranian population. Sixty-five patients met the inclusion criteria and were divided into homogenous treatment groups of EVLT (n?=?30) or HLS (n?=?35). Clinical severity, etiology, anatomy, pathophysiology (CEAP) classification and Aberdeen Varicose Vein Symptom Severity Scores (AVSS) were used to determine disease severity and symptoms before and after the procedure in both groups. Outcome was measured by the rate of recurrence as shown in Doppler ultrasonography evaluation. Follow-up was conducted 1 week and 3, 6, 12, and 18 months after the intervention. The occlusion rate of GSV was similar in both groups (93.6 % for EVLT, 88.3 for HLS) at 18 months of follow-up. The median CEAP score showed a dramatic decrease in both groups after 1 week which was sustained for the rest of the study. The Aberdeen Varicose Vein Symptom Severity score was significantly lower in the EVLT group at 12 and 18 months of follow-up. There was no significant difference in patient satisfaction in both groups. Our findings show that EVLT may offer a better long-term relief of symptoms. This, alongside its better cosmetic outcome, and less invasive anesthesia requirements may make it the favorable choice for treatment of GSV insufficiency.  相似文献   
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Among the legume foods, soy proteins are finding increased use in human diets. Hence, selected aspects of dietary mineral absorption and availability in reference to soy proteins are reviewed, with particular attention being given to the human nutritional context. Data from animal feeding studies are considered first as a basis for indicating the value, as well as limitations, of data from animal bioassays on mineral absorption as they may relate directly to human feeding. It is apparent that the availability of zinc and iron in soy-based diets given to animals is variable and it is difficult to draw generalized conclusions about legumes and mineral absorption in reference to man. The limited data obtained in human metabolic studies are reviewed and they lead to the conclusion that well-processed soy concentrates and isolates do not impair zinc absorption or nutriture. The effects of diets based on significant intakes of soy foods on the absorption of iron are still unclear although the major available evidence does not suggest significant untoward consequences of increased soy-protein intake on body iron nutriture. This problem deserves more attention, and not only with respect to iron but also other trace elements for which data in human subjects are limited or entirely lacking. Preliminary results of studies of MIT experiments, in which stable isotope probes are being developed to quantify mineral bioavailability, arc reviewed as a basis for indicating possible novel and useful approaches for exploring quantitative aspects of nutrient bioavailability in diets consumed directly by man.  相似文献   
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ObjectiveWe conducted a systematic review and dose–response meta-analysis of prospective studies to summarize findings on the associations between intakes of soy, soy isoflavones, and soy protein and risk of mortality from all causes, cancers, and cardiovascular diseases.MethodsOnline databases were systematically searched to identify relevant articles published earlier than May 2018. We applied restricted cubic splines using random-effects analysis to assess dose–response associations. Between-study heterogeneity was assessed by I2 value and Cochrane Q test. Potential publication bias was assessed by visual inspection of funnel plots and Begg regression test.ResultsIn total, 23 prospective studies with an overall sample size of 330,826 participants were included in the current systematic review and the meta-analysis. Soy/soy products consumption was inversely associated with deaths from cancers (pooled relative risk 0.88, 95% CI 0.79 to 0.99; P=0.03; I2=47.1%, 95% CI 0.0% to 75.4%) and cardiovascular diseases (pooled effect size: 0.85, 95% CI 0.72 to 0.99; P=0.04; I2=50.0%, 95% CI 0.0% to 77.6%). Such significant associations were also observed for all-cause mortality in some subgroups of the included studies, particularly those with higher quality. In addition, higher intake of soy was associated with decreased risk of mortality from gastric, colorectal, and lung cancers as well as ischemic cardiovascular diseases. Participants in the highest category of dietary soy isoflavones intake had a 10% lower risk of all-cause mortality compared with those in the lowest category. We also found that a 10-mg/day increase in intake of soy isoflavones was associated with 7% and 9% decreased risk of mortality from all cancers and also breast cancer respectively. Furthermore, a 12% reduction in breast cancer death was indicated for each 5-g/day increase in consumption of soy protein. However, intake of soy protein was not significantly associated with all-cause and cardiovascular diseases mortality.ConclusionsSoy and its isoflavones may favorably influence risk of mortality. In addition, soy protein intake was associated with a decreased risk in the mortality of breast cancer. Our findings may support the current recommendations to increase intake of soy for greater longevity.  相似文献   
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ABSTRACT

Lacrosse has gained substantial popularity across age groups in the past few decades, but epidemiologic sex differences of lacrosse injuries in emergency settings have not been well described. We characterized and described lacrosse-related injuries presenting to United States Emergency Departments (US EDs) using data from the National Electronic Injury Surveillance System (NEISS). From 1997 to 2015, 7,587 lacrosse-related injuries were treated at US EDs (national estimate of 256,358 injuries). Males accounted for 75.5% of injuries. Average age was 16.0 ± 5.0 (range 5–71) years. Sprains/strains (25.4%), contusions/abrasions (23.9%), and fractures (18.7%) were the most common diagnoses. Females sustained a higher proportion of sprains/strains (36.0%) than males (21.9%) (p< 0.01), while males sustained a higher proportion of fractures (injury proportion ratios [IPR]; 21.3% vs. 10.8%, p< 0.01). Similar proportions of concussions were observed (IPR; 6.1% in males, 6.2% among females). Differences in injury patterns may be secondary to differences in rules and equipment between the two sports.  相似文献   
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