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1.
《Plains anthropologist》2013,58(90):353-356
Abstract

Pointed wooden darts propelled by an atlatl are capable of penetrating the hide of an elephant from close range. Average penetration of 5 em is probably not sufficient to bring about the swift demise of an elephant. Greater penetration might be achieved with wood tipped darts by increasing weight and/or velocity or with narrow diameter darts. Basic information is presented to allow for better experiments in the future.  相似文献   

2.
摘要 目的:对蚌埠市蚌山区老年人群骨质疏松症进行流行病学调查,并探讨骨质疏松症对跌倒风险和认知功能的影响。方法:于2019年11月~2021年4月采用多阶段分层随机抽样的方法,抽取蚌埠市蚌山区的常住居民,调查老年人群骨质疏松症发生率,共发放960份调查问卷,回收941份,回收率为98.02%。根据有无骨质疏松症分为骨质疏松症组和无骨质疏松症组,观察两组跌倒风险和认知功能状况。应用多因素logistic回归分析老年人群发生骨质疏松症的危险因素和保护因素。结果:941例研究对象中,检查出存在骨质疏松症者325人,发病率为34.54%。根据有无骨质疏松症分为骨质疏松症组(n=325)和无骨质疏松症组(n=616)。单因素分析结果显示,老年人群发生骨质疏松症与乳制品和钙片摄入情况、年龄、连续服用类固醇激素超过3个月情况、骨折史、性别、其他慢性病患病情况、体质量指数、婚姻状况、饮茶情况、每天运动情况有关(P<0.05)。多因素logistic回归性分析,结果显示:年龄≥70岁、性别为女性、连续服用类固醇激素超过3个月情况是老年人群发生骨质疏松症的危险因素,而每天运动情况≥30 min、有乳制品和钙片摄入情况、体质量指数≥24 kg/m2是老年人群发生骨质疏松症的保护因素(P<0.05)。骨质疏松症组的跌倒风险评估工具(FROP-Com)评分高于无骨质疏松症组,跌倒效能量表(MFES)评分低于无骨质疏松症组(P<0.05)。骨质疏松症组的简明精神状态检查量表(MMSE)评分低于无骨质疏松症组,画钟试验(CDT)评分高于无骨质疏松症组(P<0.05)。结论:蚌埠市蚌山区老年人群骨质疏松症患病率较高,且受到年龄、性别、连续服用类固醇激素超过3个月情况等因素的影响,而每天运动情况≥30 min、乳制品和钙片摄入情况、体质量指数≥24 kg/m2可减少骨质疏松症患病率,同时存在骨质疏松症的患者其跌倒风险升高,认知功能下降。  相似文献   

3.
Although the belief that overuse can harm pitchers is widespread, there exists little evidence to show that the number of pitches thrown and the days of rest affect future performance and injury among adults. The purpose of this study is to quantify the effects of pitches thrown and the days of rest on pitcher performance. We examined performances of major-league baseball starting pitchers from 1988 to 2009 using fractional polynomial multiple regression to estimate the immediate and cumulative impact of pitches thrown and the days of rest on performance, while controlling for other factors that likely affect pitcher effectiveness. Estimates indicate each pitch thrown in the preceding game increased earned run average (ERA) by 0.007 in the following game. Each pitch averaged in the preceding 5 and 10 games increased the ERA by 0.014 and 0.022, respectively. Older pitchers were more sensitive to cumulative pitching loads than younger pitchers were, but they were less affected by pitches thrown in the preceding game. Rest days were weakly associated with performance. In summary, we found that there is a negative relationship between past pitches thrown and future performance that is virtually linear. The impact of the cumulative pitching load is larger than the impact of a single game. Rest days do not appear to have a large impact on performance. This study supports the popular notion that high pitching loads can dampen future performance; however, because the effect is small, pitch-count benchmarks have limited use for maintaining performance and possibly preventing injury.  相似文献   

4.
目的:统计先天性心脏病(CHD)患儿术后医院感染的病原菌分布及细菌耐药性情况,分析影响CHD患儿术后医院感染的危险因素。方法:回顾性选取2010年3月-2017年10月我院行CHD手术治疗的患儿3800例,收集临床标本进行致病菌培养并进行药敏试验,统计CHD术后医院感染患儿病原菌种类及主要致病菌的耐药情况,分析影响CHD患儿术后医院感染的危险因素。结果:3800例CHD患儿术后医院感染率为3.13%(119/3800),共分离出菌株172株,G-菌、G+菌、真菌分别占55.81%(96/172)、26.74%(46/172)、17.44%(30/172)。肺炎克伯雷菌、大肠杆菌对头孢类抗生素高度耐药,鲍曼不动杆菌检出率逐年增高,且仅对多黏菌素B保持敏感;肺炎链球菌、凝固酶阴性葡萄球菌、金黄色葡萄球菌对大环内脂类抗生素、克林霉素、青霉素高度耐药,对万古霉素和替加环素保持敏感。术后医院感染与年龄、体重、病程、手术时间、体外循环时间、机械通气时间、ICU停留时间、住院时间、合并肺动脉高压、吸痰次数、静脉营养、应用丙种球蛋白或白蛋白有关(P<0.05),且合并肺动脉高压、体外循环时间≥100 min、机械通气时间≥120 h、吸痰次数≥5次/d是CHD患儿术后医院感染的危险因素(P<0.05)。结论:G-菌、G+菌是CHD患儿术后医院感染的主要致病菌,且对常用抗生素高度耐药,此外鲍曼不动杆菌的检出率和耐药性上升极为明显,合并肺动脉高压、体外循环时间及机械通气时间过长、吸痰次数多的CHD患儿医院感染风险升高。  相似文献   

5.
《Cytotherapy》2022,24(12):1190-1194
Background aimsAllogeneic hematopoietic stem cell transplantation (allo-HSCT) is an effective treatment for patients with hematological malignancies; however, allo-HSCT does not come without the cost of treatment-related morbidity and mortality. Early detection of risk factors could be helpful in identifying patients who could benefit from early interventions. Many patients gain weight during the allo-HSCT treatment, although little is known about the impact of weight gain.MethodsWeight gain in 146 consecutively enrolled adult patients undergoing allo-HSCT was explored.ResultsIn total, 141 patients (97%) gained weight along the course of allo-HSCT. Median weight increase was 4.8 kg (range 0.0–16.1 kg), with median increase in body weight 6.5% (range 0.0%–30.8%). Maximum weight increase was observed at day +7 (range day –8, +44). Weight gain was associated with increased incidence of acute graft-versus-host disease. Patients with weight gain >10% had a significantly greater 5-year mortality compared with those with lower weight gain (P = 0.031, rank sum test).ConclusionsWeight gain is a simple variable with the ability to provide prognostic information for patients undergoing allo-HSCT.  相似文献   

6.
The effects of a high-fat diet supplying a constant energy/protein ratio, with and without overeating, on energy intake and expenditure was studied in mature male rats. A control group (LF) received ad libitum access to a low-fat diet. Body weight gain, efficiency of food utilization, and dietary-induced thermogenesis were increased relative to controls in a group with ad libitum access to the high-fat diet (HF-A), but not in a group which was pair fed the diet (HF-P) in amounts (kcal) equal to that of LF animals. However, the individual variability within the HF-A group was high for each measure. An arbitrary separation of that group into 2 subgroups (based on high vs low weight gain) produced one subgroup with increased efficiency, greater weight gain and no change in dietary-induced thermogenesis (HF-AH), and another with no difference in efficiency or in weight gain from the LF group but which had higher dietary-induced thermogenesis (HF-AL). Food intake was slightly, but not significantly, greater for the HF-AH subgroup than for the HF-AL subgroup. We conclude that rats can increase thermogenesis in response to overeating but that the increase is highly variable. The thermogenic response appears to be related to the overeating rather than to the fat content of the diet.  相似文献   

7.
《Endocrine practice》2010,16(1):71-79
ObjectiveTo examine the performance of weightbased formulae for estimating the levothyroxine dosage requirement in athyreotic patients and to determine whether formula performance is affected by age, sex, or menstrual status.MethodsIn this prospective study, euthyroid study participants aged 18 to 65 years were followed up after total thyroidectomy at 4 time points: 6-8 weeks, 12-16 weeks, 6 months, and 1 year. Patient weight, serum thyrotropin concentration, and levothyroxine dosage required were recorded at each time point. The postoperative starting levothyroxine dosage was 1.7 mcg/kg daily for patients with benign thyroid disease and 2.2 mcg/kg daily for patients with thyroid cancer. Actual body weight was used to calculate the initial dosage. At steady state, adjustments were made in each patient’s levothyroxine dosage until the target thyrotropin concentration was reached. The levothyroxine dosage required to achieve this goal was documented.ResultsFifty patients were included (37 women, 13 men). Formulae based on actual body weight were accurate in achieving a normal thyrotropin concentration in 48% to 75% of participants. Final dosages to achieve normal thyrotropin values were similar in men (1.43 mcg/kg daily) and menopausal women (1.68 mcg/kg daily), but higher in premenopausal women (2.10 mcg/kg daily). When a formula based on ideal body weight was used, the requirement for menopausal women (2.34 mcg/kg daily) was similar to that of premenopausal women (2.44 mcg/kg daily), but the requirement for men (1.73 mcg/kg daily) remained lower than that observed in both female groups.ConclusionsWhen actual body weight was used to calculate levothyroxine dosage requirement, premenopausal women appeared to have a greater requirement than either menopausal women or men. When ideal weight was used, the requirement of all women was greater than that of men. Perhaps with formulae using actual weight, this apparent sex difference is masked by the greater weight, older age, or altered hormonal milieu of menopausal women. (Endocr Pract. 2010;16:71-79)  相似文献   

8.
Abstract

Aim: Cardiac autonomic neuropathy (CAN) is a common and important chronic complication in diabetic patients. Heart failure resulting from cardiomyopathy is also a lethal complication in diabetic patients. However, data showing the exact association between CAN and heart failure in diabetic patients are relatively scarce. Therefore, our study aimed to determine the association between the parameters assessing CAN and heart function in diabetic patients.

Method: The medical records of type 2 diabetic patients who underwent an autonomic function test with heart rate variability (HRV) and echocardiography were reviewed from January 2018 to December 2018. A total of 100 type 2 diabetic patients were included, and the association between the parameters assessing CAN and heart function was analysed.

Results: Among the 100 analysed patients, 65 were diagnosed with CAN and 26 showed diastolic dysfunction. Moreover, 19 (73.1%) diabetic patients with diastolic dysfunction were complicated with CAN. The occurrence of diastolic dysfunction was higher in diabetic patients with CAN than in diabetic patients without CAN (29.2% vs 20.0%, p?<?0.05), and the occurrence of CAN was higher in diabetic patients with diastolic dysfunction than in patients without diastolic dysfunction (73.1% vs 62.2%, p?<?0.05). However, there were no significant associations between HRV parameters and heart function.

Conclusion: We demonstrated that diastolic dysfunction is more common in diabetic patients complicated with CAN than in diabetic patients without CAN, although several diabetic patients without diastolic dysfunction are also diagnosed with CAN. Moreover, further studies about the long-term serial monitoring of heart function according to the progression of CAN are required to confirm the exact association between CAN and heart function.  相似文献   

9.
Meng X  Dai X  Liao TD  D'Ambrosio M  Wang F  Yang JJ  Yang XP 《Life sciences》2011,88(3-4):178-186
AimsWe previously found that in mice with experimental myocardial infarction (MI), 17β-estradiol (E2) increased mortality and worsened cardiac remodeling and these deleterious effects were associated with renal enlargement and hydronephrosis in a dose-dependent manner. In the present study we questioned whether E2-induced renal damage predisposes to rather than results from its adverse effects on the heart.Main methodsOvariectomized (ovx) mice received either placebo (P) or E2 at 0.02 (E2-L, low dose), 0.42 (E2-M, moderate dose) or 4.2 μg/d (E2-H, high dose) for 8 weeks.Key findingsE2-L partially restored uterine weight and plasma estrogen levels without affecting heart, lung and liver weight, hemodynamic parameters, or heart and kidney morphology and function. E2-M restored normal uterine weight, but this was accompanied by a significant increase in kidney weight, albuminuria, glomerular matrix formation and markers for oxidative stress. E2-H increased uterine weight 4.5-fold and resulted in higher plasma creatinine levels, severe albuminuria, renal tubular dilatation, tubulointerstitial injury, hydronephrosis, glomerulosclerosis and oxidative stress. E2-H also caused ascites, hepatomegaly and fluid retention in the uterine horns but had no significant effect on blood pressure or heart function.SignificanceOur data demonstrated that an excessive dose of E2 that raises uterine weight beyond physiological levels adversely affects the kidney even before it damages the heart. We believe estrogen dosage should be taken into account when considering hormonal replacement therapy, since inappropriate doses of E2 may damage not only the heart but also the kidney.  相似文献   

10.
Aim of the studyTo assess the feasibility of early stress and rest myocardial perfusion and function study using a fast 99mTc-tetrofosmin gated-SPECT protocol in patients with known coronary artery disease.Materials and methodsForty-three patients (pts) (37 M, 6 F, mean age 63.8 ± 9.8 years) underwent a 99mTc-Tetrofosmin gated-SPECT (Axis Picker-Philipps®) myocardial study and a coronary angiography (CA) within 3 months. Images were acquired (LEHR, eight bins, 40 sec per image) after injection of 99mTc-tetrofosmin (200 to 380 MBq) early (15 min) post-stress (36 dipyridamole, two dobutamine and five ergometric stress), and at rest after 99mTc-tetrofosmin reinjection (600 to 1150 MBq), in a total time not exceeding 2 hours. Processing was performed with QGS® software using the 17-segment model. Pathological study was defined as a summed difference score (SDS) greater than or equal to 4 4, a fixed defect with summed rest score greater than or equal to 4 and/or LV dysfunction defined as myocardial stunning (variation between stress and rest LVEF greater than or equal to 4 5%), stress LVEF less than or equal to 45% or rest LVEF less than or equal to 40%. Results were compared with CA, and stenosis greater than or equal to 4 50% was considered as significant.ResultsFor 100% the quality of SPECT imaging was good or excellent. For six patients gating was impossible because of arrhythmia. The overall sensitivity, specificity and accuracy were 95%, 50%, and 91%, respectively. The concordance between gated SPECT and CA was moderate (kappa = 0.45, SE = 0.15). Interestingly, early-gated acquisition permitted to underline left ventricular dysfunction in 11 cases (30%), of whom eight had polyvascular disease. Stunning was detected in six of 37 cases (16%), of whom six had polyvascular disease.ConclusionA one-day two-hour 99mTc-tetrofosmin gated-SPECT protocol to assess left ventricular perfusion and function is feasible and accurate. Early gated acquisition proves helpful for detecting post-stress stunning, which is a well known crucial prognostic factor of major cardiac events, and could help to speed up clinical management.  相似文献   

11.
《Endocrine practice》2013,19(2):243-251
ObjectiveReports of concomitant diabetic ketoacidosis (DKA) and acute pancreatitis (AP) are lacking among emerging forms of diabetes. This longitudinal study characterized ketosis-prone diabetes (KPD) in patients presenting with concomitant AP and DKA.MethodsMulti-ethnic KPD patients (N = 755) were followed prospectively for 1 year from the time of index DKA using repeated metabolic and beta cell functional reserve measures. Baseline and longitudinal characteristics were compared between KPD patients whose index DKA was associated with (n = 54) or without (n = 701) AP.ResultsThe AP group had significantly higher baseline serum amylase, lipase, and triglyceride levels and significantly lower bicarbonate levels than the non-AP group. AP patients had significantly greater C-peptide area-under-the-curve with glucagon stimulation shortly after the index DKA, and higher fasting C-peptide (FCP) levels 6 to 12 months later. Using the validated "Aβ" KPD classification, 85% of AP patients had β+ status (preserved beta cell functional reserve), compared to 60% of non-AP patients (P = .04). Multivariate analysis revealed that among the β+ KPD subgroup with an identifiable precipitating factor for DKA ("provoked" DKA), patients with AP had worse long-term glycemic outcomes than patients whose DKA was associated with other factors.ConclusionDespite greater clinical severity at presentation, KPD patients with AP have better preserved beta cell function than those without AP. β+ KPD patients presenting with AP have worse long-term glycemic control than those with other causes of provoked DKA. Factors other than beta cell function negatively impact glycemic control in KPD patients presenting with AP.  相似文献   

12.
PurposeIt has been proposed that pelvic girdle pain (PGP) subjects adopt a high load motor control strategy during the low load task of the active straight leg raise (ASLR). This study investigated this premise by observing the motor control patterns adopted by pain free subjects during a loaded ASLR (ASLR + PL).MethodTrunk muscle activation, intra-abdominal pressure, intra-thoracic pressure, pelvic floor motion, downward pressure of the non-lifted leg and respiratory rate were compared between resting supine, ASLR and ASLR + PL. Additionally, side-to-side comparisons were performed for ASLR + PL.ResultsIncremental increases in muscle activation were observed from resting supine to ASLR to ASLR + PL. During the ASLR + PL there was a simultaneous increase in intra-abdominal pressure with a decrease in intra-thoracic pressure, while respiratory fluctuation of these variables were maintained. The ASLR + PL also resulted in increased pelvic floor descent and greater downward pressure of the non-lifted leg. Trunk muscle activation was comparable between sides during ASLR + PL in all muscles except lower obliquus internus abdominis, which was more active on the leg lift side.ConclusionPain free subjects respond to an ASLR + PL by a general increase in anterior trunk muscle activation, but preserve the pattern of greater activation on the side of the leg lift observed during an unloaded ASLR. This contrasts to findings in PGP subjects who, despite having a high load strategy for performing an ASLR on the symptomatic side of the body, display equal bilateral activation of the anterior abdominal wall during the ASLR. This differentiates PGP subjects from pain free subjects, supporting the notion that PGP subjects have aberrant motor control patterns during an ASLR.  相似文献   

13.
《Endocrine practice》2011,17(4):e104-e108
ObjectiveTo present an unusual case of calciphylaxis in an obese patient with inactive rheumatoid arthritis and normal renal function.MethodsWe describe a 46-year-old morbidly obese Caucasian woman who had previously weighed 200 kg and presented with painful leg ulcers following a rapid weight loss of 102 kg in 1 year.ResultsThe subject was admitted with a 6-week history of painful leg ulcers that progressed to her thighs. Vasculitis and active rheumatoid arthritis were excluded clinically and biochemically. A skin biopsy confirmed calciphylaxis in the context of normal renal function. Serum 25-hydroxyvitamin D was low at 14 ng/mL (reference range, 20 to 200 ng/mL), with an elevated serum parathyroid hormone level of 241 pg/mL (reference range, 10 to 65 pg/mL), but normal serum calcium and phosphorus levels. The skin lesions persisted despite local wound care, daily hyperbaric oxygen, and parenteral sodium thiosulfate therapies. After normalizing the serum vitamin D level through oral supplementation, she responded well to pamidronate infusion with complete healing of the ulcers and regained 13% of her premorbid weight.ConclusionThis is the first case of calciphylaxis preceded by weight loss of greater than 100 kg in a patient with hypovitaminosis D who responded to pamidronate therapy. (Endocr Pract. 2011;17:e104-e108)  相似文献   

14.
《Endocrine practice》2021,27(4):312-317
ObjectiveObesity is increasing worldwide, and certain endocrine disorders may contribute to weight gain. While several studies have examined the association between weight gain and prolactinomas, the results are conflicting. Therefore, this study aimed to determine if body mass index (BMI) is higher among those with prolactinomas than those without.MethodsWe identified patients ≥18 years of age referred to an endocrine clinic between 2008 and 2018 with newly diagnosed prolactinomas. We extracted the relevant information, and comparative data was obtained from the 2015-2016 National Health and Nutrition Examination Survey.ResultsIn total, 34 cases met the inclusion criteria. One third of the patients described weight gain at presentation. Those with prolactinomas had a significantly higher BMI than the National Health and Nutrition Examination Survey population (median BMI, 29.8 kg/m2 vs 28.3 kg/m2, P = .0048). When stratified by sex, only men with prolactinomas had an increased BMI compared with the controls. Moreover, those with prolactinomas had a higher prevalence of class II obesity (BMI ≥ 35 kg/m2) than the survey population (35% vs 18%, P = .01). Among the prolactinoma patients, a correlation was observed between BMI and log-transformed prolactin levels (R2 = 0.4, P = .0002).ConclusionWeight gain can be a presenting symptom for patients with newly diagnosed prolactinomas. Those with prolactinomas have a higher BMI and an increased prevalence of class II obesity. These findings suggest that patients should be counseled regarding weight issues related to prolactinomas at presentation and should be a consideration in the investigative and treatment algorithm of prolactinomas.  相似文献   

15.
目的:探讨重复经颅磁刺激(rTMS)对慢性精神分裂症患者认知功能的影响。方法:100例慢性精神分裂症患者,按照随机数字表法分为rTMS真刺激组和伪刺激组,每组各50例。采用阳性与阴性症状量表(PANSS)及副反应量表(TESS)评估患者治疗前后精神症状及不良反应;采用威斯康星卡片分类测验(WCST)及可重复的成套神经心理状态测量(RBANS)评价患者治疗前后认知功能。结果:治疗后,rTMS真刺激组PANSS总分、阳性量表分、阴性量表分、一般精神病理量表分均明显降低(P0.05),且均明显低于伪刺激组(P0.05),两组治疗前后及组间TESS评分无明显差异(P0.05);rTMS真刺激组WCST中的概念化水平百分数明显高于伪刺激组(P0.05),总时间及错误思考时间短于伪刺激组(P0.05);rTMS真刺激组RBANS中视觉广度与延迟记忆成绩明显提高(P0.05),且视觉广度明显高于伪刺激组(P0.05);rTMS真刺激组2例患者首次治疗后出现轻度不适症状,随访3个月所有患者均无不适主诉。结论:rTMS治疗对慢性精神分裂症患者的部分认知功能有一定的改善作用,且安全性较高,值得进一步研究。  相似文献   

16.
PurposeA Geant4 model of a novel, water-equivalent electronic portal imaging device (EPID) prototype for radiotherapy imaging and dosimetry utilising an array of plastic scintillating fibres (PSFs) has been developed. Monte Carlo (MC) simulations were performed to quantify the PSF-EPID imaging performance and to investigate design aspects affecting performance for optimisation.MethodsUsing the Geant4 model, the PSF-EPID’s imaging performance for 6 MV photon beams was quantified in terms of its modulation transfer function (MTF), noise power spectrum (NPS) and detective quantum efficiency (DQE). Model parameters, including fibre dimensions, optical cladding reflectivity and scintillation yield, were varied to investigate impact on imaging performance.ResultsThe MC-calculated DQE(0) for the reference PSF-EPID geometry employing 30 mm fibres was approximately nine times greater than values reported for commercial EPIDs. When using 10 mm long fibres, the PSF-EPID DQE(0) was still approximately three times greater than that of a commercial EPID. Increased fibre length, cladding reflectivity and scintillation yield produced the greatest decreases in NPS and increases in DQE.ConclusionsThe potential to develop an optimised next-generation water-equivalent EPID with MV imaging performance at least comparable to commercial EPIDs has been demonstrated. Factors most important for optimising prototype design include fibre length, cladding reflectivity and scintillation yield.  相似文献   

17.
BackgroundWomen with obesity and infertility are counseled to lose weight prior to conception and infertility treatment to improve pregnancy rates and birth outcomes, although confirmatory evidence from randomized trials is lacking. We assessed whether a preconception intensive lifestyle intervention with acute weight loss is superior to a weight neutral intervention at achieving a healthy live birth.Methods and findingsIn this open-label, randomized controlled study (FIT-PLESE), 379 women with obesity (BMI ≥ 30 kg/m2) and unexplained infertility were randomly assigned in a 1:1 ratio to 2 preconception lifestyle modification groups lasting 16 weeks, between July 2015 and July 2018 (final follow-up September 2019) followed by infertility therapy. The primary outcome was the healthy live birth (term infant of normal weight without major anomalies) incidence. This was conducted at 9 academic health centers across the United States. The intensive group underwent increased physical activity and weight loss (target 7%) through meal replacements and medication (Orlistat) compared to a standard group with increased physical activity alone without weight loss. This was followed by standardized empiric infertility treatment consisting of 3 cycles of ovarian stimulation/intrauterine insemination. Outcomes of any resulting pregnancy were tracked. Among 191 women randomized to standard lifestyle group, 40 dropped out of the study before conception; among 188 women randomized to intensive lifestyle group, 31 dropped out of the study before conception. All the randomized women were included in the intent-to-treat analysis for primary outcome of a healthy live birth. There were no significant differences in the incidence of healthy live births [standard 29/191(15.2%), intensive 23/188(12.2%), rate ratio 0.81 (0.48 to 1.34), P = 0.40]. Intensive had significant weight loss compared to standard (−6.6 ± 5.4% versus −0.3 ± 3.2%, P < 0.001). There were improvements in metabolic health, including a marked decrease in incidence of the metabolic syndrome (baseline to 16 weeks: standard: 53.6% to 49.4%, intensive 52.8% to 32.2%, P = 0.003). Gastrointestinal side effects were significantly more common in intensive. There was a higher, but nonsignificant, first trimester pregnancy loss in the intensive group (33.3% versus 23.7% in standard, 95% rate ratio 1.40, 95% confidence interval [CI]: 0.79 to 2.50). The main limitations of the study are the limited power of the study to detect rare complications and the design difficulty in finding an adequate time matched control intervention, as the standard exercise intervention may have potentially been helpful or harmful.ConclusionsA preconception intensive lifestyle intervention for weight loss did not improve fertility or birth outcomes compared to an exercise intervention without targeted weight loss. Improvement in metabolic health may not translate into improved female fecundity.Trial registrationClinicalTrials.gov NCT02432209.

Richard Legro and colleagues investigate the impact of a preconception weight loss intervention on healthy live birth rates in women with obesity and unexplained infertility.  相似文献   

18.
AimLoss of muscle strength and balance are main characteristics of physical frailty in old age. Postural sway is associated with muscle contractile capacity and to the ability of rapidly correcting ankle joint changes. Thus, resistance training would be expected to improve not only strength but also postural balance.MethodsIn this study, age-matched older individuals (69.9±1.3 years) were randomly assigned to flywheel (n=12), or weight-lifting (n=12) groups, training the knee extensors thrice weekly for 12 weeks. The hypotheses were that owing to a larger eccentric loading of the knee extensors, flywheel training would result in (a) greater gains in quadriceps strength; (b) greater improvements in balance performance compared with weight-lifting training. Isokinetic dynamometry, B-mode ultrasonography, electromyography, percutaneous muscle stimulation and magnetic resonance imaging were employed to acquire the parameters of interest.ResultsFollowing training, knee extensors peak isokinetic power increased by 28% (P<0.01) in the flywheel group with no change in the weight-lifting group. Adaptations of the gastrocnemius muscle also occurred in both groups. The gastrocnemius characteristic with the highest response to training was tendon stiffness, with increases of 54% and 136% in the weight-lifting and flywheel groups, respectively (P<0.01). The larger increase in tendon stiffness in the flywheel group was associated with an improvement in postural balance (P<0.01).ConclusionQuadriceps flywheel loading not only produces a greater increase in power than weight training but its physiological benefits also transfer/overspill to the plantarflexor muscle–tendon unit resulting in a significantly improved balance. These findings support our initial hypotheses.  相似文献   

19.
Background/objectivesLiquid fructose associates with prevalence of type 2 diabetes mellitus and obesity. Intervention studies suggest that metabolically unfit individuals are more responsive than healthy individuals to liquid fructose. We determined whether mice consuming an obesogenic Western diet were more responsive than chow-fed mice to the alterations induced by liquid fructose supplementation (LFS).MethodsC57BL/6N mice were fed chow or Western diet±ad libitum 15% fructose solution for 12 weeks. Food and liquid intake and body weight were monitored. Plasma analytes and liver lipids, histology and the expression of genes related to lipid handling, endoplasmic reticulum stress, inflammation and insulin signaling were analyzed.ResultsWestern diet increased energy intake, visceral adipose tissue (vWAT), body weight, plasma and liver triglycerides and cholesterol, and inflammatory markers in vWAT vs. chow-fed mice. LFS did not change energy intake, vWAT or body weight. LFS significantly increased plasma and liver triglycerides and cholesterol levels only in Western-diet-fed mice. These changes associated with a potentiation of the increased liver expression of PPARγ and CD36 that was observed in Western-fed mice and related to the increased liver mTOR phosphorylation induced by LFS. Furthermore, LFS in Western-diet-fed mice induced the largest reduction in liver IRS2 protein and a significant decrease in whole-body insulin sensitivity.ConclusionsLFS in mice, in a background of an unhealthy diet that already induces fatty liver visceral fat accretion and obesity, increases liver lipid burden, hinders hepatic insulin signaling and diminishes whole-body insulin sensitivity without changing energy intake.  相似文献   

20.
Little work has been done to examine the deep squat position (>130° sagittal knee flexion). In baseball and softball, catchers perform this squat an average of 146 times per nine-inning game. To alleviate some of the stress on their knees caused by this repetitive loading, some catchers wear foam knee supports.ObjectivesThis work quantifies the effects of knee support on lower-body joint kinematics and kinetics in the deep squat position.MethodsSubjects in this study performed the deep squat with no support, foam support, and instrumented support. In order to measure the force through the knee support, instrumented knee supports were designed and fabricated. We then developed an inverse dynamic model to incorporate the support loads. From the model, joint angles and moments were calculated for the three conditions.ResultsWith support there is a significant reduction in the sagittal moment at the knee of 43% on the dominant side and 63% on the non-dominant side compared to without support. These reductions are a result of the foam supports carrying approximately 20% of body weight on each side.ConclusionKnee support reduces the moment necessary to generate the deep squat position common to baseball catchers. Given the short moment arm of the patella femoral tendon, even small changes in moment can have a large effect in the tibial-femoral contact forces, particularly at deep squat angles. Reducing knee forces may be effective in decreasing incidence of osteochondritis dissecans.  相似文献   

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