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81.
Jorge Gutirrez-Hellín Juan Del Coso Milln Aguilar-Navarro David Varillas-Delgado Carlos Ruiz-Moreno lvaro Lpez-Samans Francisco J. Amaro-Gahete Alejandro Muoz 《Nutrients》2022,14(23)
p-Synephrine is deemed a safe and effective substance to increase fat utilization during exercise of low-to-moderate intensity in men but not in women. Additionally, the existence of a diurnal variation in substrate utilization has been documented during exercise with enhanced fat oxidation in the evening compared with early morning. However, it remains unknown whether there is an interaction between the effect of p-synephrine and the time of the day on fat oxidation during exercise. This study aimed to evaluate the effect of the acute ingestion of 3 milligram of p-synephrine per kilogram of body mass (mg/kg) on fat oxidation during exercise of increasing intensity when the exercise is performed in the morning vs. the evening. Using a randomized, double-blind, placebo-controlled experimental design, 16 healthy and active women performed four identical exercise trials after the ingestion of 3 mg/kg of p-synephrine and 3 mg/kg of a placebo (cellulose) both in the morning (8–10 am) and in the evening (5–7 pm). In the exercise trials, the substances were ingested 60 min before an incremental test on a cycle ergometer with 3 min stages at workloads from 30 to 80% of maximal oxygen uptake (VO2max). Substrate oxidation rates were measured by indirect calorimetry. In each trial, the maximum rate of fat oxidation (MFO) and the intensity that elicited MFO (Fatmax) were measured. A two-way analysis of variance (time-of-the day × substance) was used to detect differences among the trials. With the placebo, MFO was 0.25 ± 0.11 g/min in the morning and 0.24 ± 0.07 g/min in the evening. With p-synephrine, MFO was 0.26 ± 0.09 g/min in the morning and 0.21 ± 0.07 g/min in the evening. There was no main effect of substance (p = 0.349), time of day (p = 0.186) and the substance × time of day (p = 0.365) on MFO. Additionally, Fatmax was reached at a similar exercise intensity with the placebo (41.33 ± 8.34% VO2max in the morning and 44.38 ± 7.37% VO2max in the evening) and with p-synephrine (43.33 ± 7.24% VO2max in the morning and 45.00 ± 7.43% VO2max in the evening), irrespective of the time of day with no main effect of substance (p = 0.633), time of day (p = 0.191), or interaction (p = 0.580). In summary, the acute intake of 3 mg/kg of p-synephrine before exercise did not increase MFO and Fatmax, independently of the time of day, in female athletes. This indicates that the time of day is not a factor explaining the lack of effectiveness of this substance to enhance fat oxidation during aerobic exercise in women. 相似文献
82.
Elena N. Venable Lily A. Seynaeve Scott T. Beale Albert Gamez Jr. Antoinette Domingo Michael D. Rosenthal Mitchell J. Rauh 《International Journal of Sports Physical Therapy》2022,17(6):1053
BackgroundFemale collegiate cross-country (XC) runners have a high incidence of running-related injury (RRI). Limited reports are available that have examined potential intrinsic factors that may increase RRI risk in this population.PurposeTo examine the relationships between RRI, hip muscle strength, and lower extremity running kinematics in female collegiate XC runners.Study DesignProspective observational cohort.MethodsParticipants included twenty female NCAA collegiate XC runners from Southern California universities who competed in the 2019-20 intercollegiate season. A pre-season questionnaire was used to gather demographic information. Hip muscle strength was measured with isokinetic dynamometry in a sidelying open-chain position and normalized by the runner’s body weight (kg). Running kinematic variables were examined using Qualisys 3D Motion Capture and Visual 3D analysis. RRI occurrence was obtained via post-season questionnaires. Independent t-tests were used to determine mean differences between injured and non-injured runners for hip abductor muscle strength and selected running kinematics. Pearson correlation coefficients were calculated to examine relationships between hip muscle performance and kinematic variables.ResultsEnd-of-the-season RRI information was gathered from 19 of the 20 participants. During the 2019-20 XC season, 57.9% (11 of 19) of the runners sustained an RRI. There were no significant differences between mean hip abductor normalized muscle strength (p=0.76) or mean normalized hip muscle strength asymmetry (p=0.18) of injured and non-injured runners during the XC season. Similarly, no significant differences were found between mean values of selected kinematic variables of runners who did and who did not report an RRI. Moderate relationships were found between hip abductor strength variables and right knee adduction at footstrike (r=0.50), maximum right knee adduction during stance (r=0.55), left supination at footstrike (r=0.48), right peak pronation during stance (r=-0.47), left supination at footstrike (r=0.51), and right peak pronation during stance (r=-0.54) (all p≤0.05).ConclusionsHip abduction muscle strength, hip abduction strength asymmetry, and selected running kinematic variables were not associated with elevated risk of RRI in female collegiate XC runners.Level of Evidence 相似文献
83.
Allison Kuntz Olivia Peters Andrew Bello Ryan Perkins Ryan Monti Leigh Murray 《International Journal of Sports Physical Therapy》2022,17(7):1318
BackgroundAnterior cruciate ligament (ACL) injury causes physical, mental, and financial burdens. Therefore, it is imperative to screen, identify, and educate athletes who are at high-risk. The combination of screening and education could identify those at risk and potentially reduce future injuries.PurposeThe purpose was to conduct a feasible community pre-season screening program for high school female athletes for the presence of known modifiable risk factors that predispose them to sustaining a non-contact ACL injury.Study DesignNon-experimental prospective studyMethodsA convenience sample of 15 healthy female athletes were recruited from local high schools, consisting of 11 soccer players and four basketball players. A pre-season screening program was designed encompassing four stations that addressed modifiable neuromuscular and biomechanical risk factors including range of motion (ROM), jump-landing technique, strength, and balance. Athletes were categorized into high-risk versus low-risk groups based on cutoff scores previously established in the literature.ResultsEvery athlete met the high-risk cutoff score for at least one extremity during the ROM screening, and some met high-risk cutoff scores for more than one ROM. Out of all four categories tested, lower extremity ROM demonstrated the greatest deficits.ConclusionThis study identified athletes as having multiple modifiable risk factors that can be addressed with training and exercises. This supports implementing a pre-season program aimed at screening for injury risk factors.Level of EvidenceLevel 3 相似文献
84.
目的观察排卵汤联合枸橼酸氯米芬(CC)治疗多囊卵巢综合征(PCOS)不孕症临床疗效。方法将139例PCOS不孕症患者随机分为3组。对照1组46例予CC治疗,对照2组47例予CC、注射用尿促性素(HMG)治疗,治疗组46例予排卵汤联合CC治疗。观察子宫内膜厚度、排卵率、妊娠率、未破裂卵泡黄素化(LUF)、多胎率及流产率等。结果治疗组流产率、多胎率均低于对照1组、对照2组(P0.05);治疗组子宫内膜厚度为8~12 mm患者百分率及妊娠率高于对照1组、对照2组(P0.05)。结论排卵汤联合CC治疗PCOS患者可以获得满意的周期妊娠率,并降低并发症的发生。 相似文献
85.
中重型子宫内膜异位症合并不孕用两种控制性超促排卵方案行体外受精-胚胎移植结局的比较 总被引:1,自引:0,他引:1
目的:比较中重型子宫内膜异位症合并不孕患者用两种控制性超促排卵方案行体外受精-胚胎移植(IVF-ET)的结局。方法:将2003年1月至2008年1月以超长方案行IVF-ET的中重型子宫内膜异位症不孕患者52例为研究组,按1:2配对选择同期用长方案患者104例为对照组。比较两组患者周期取消率、Gn起始剂量、Gn总量、获卵数、子宫内膜厚度、受精率、妊娠率、种植率、异位妊娠率及流产率。结果:两组周期取消率、获卵数、受精率、子宫内膜厚度、流产率及异位妊娠率均无显著差异(P>0.05);研究组Gn起始剂量及Gn总量均高于对照组,有显著差异(P<0.05);研究组妊娠率及种植率高于对照组,但无显著差异(P>0.05)。结论:中重型子宫内膜异位症合并不孕患者行IVF-ET时,用超长方案比用长方案会增加Gn起始剂量及总量,且有提高妊娠率及种植率的趋势。 相似文献
86.
87.
解脲脲原体血清型3在小鼠生殖道中的致病性 总被引:1,自引:0,他引:1
目的 探讨不同浓度解脲脲原体血清型3(UU3)在小鼠生殖道中的致病性.方法 将156只昆明小鼠按完全随机设计法分为A、B、c组(每组各48只)及对照组(12只)共4组.将3种不同浓度的UU3接种至各实验组小鼠阴道内,各组的浓度分别为:A组1×107 copy/g,B组1×106copy/g,c组1×105 copy/g;对照组仅接种UU液体培养基.于接种后第1、3、7、14、21、35天每次随机处死A、B、c组各8只及对照组2只小鼠,取宫颈管分泌物,荧光定量PCR(FQ-PCR)技术检测各组UU3的浓度及阳性率;取宫颈、子宫内膜及输卵管组织,光镜下观察其形态,并计算致病率.结果(1)A、B、C 3组UU3总阳性率分别为63%(30/48)、50%(24/48)和17%(8/48),3组间比较,差异有统计学意义(P<0.01).接种后1、3、7、14、21、35 d小鼠的UU3阳性率,A组分别为8/8、7/8、6/8、5/8,4/8和0,B组分别为7/8、5/8、5/8、4/8、3/8和0,C组分别为3/8、2/8、2/8、1/8、0和0;对照组各时间点均为0.接种后1 d的UU3阳性率3组间比较,差异有统计学意义(P<0.05);其他各时间点3组间比较,差异均无统计学意义(P>0.05).(2)在UU3检测阳性者中,A、B、C组的UU3浓度在接种后1、3、7、14、21 d分别为1.70×107、3.75×106和1.45×105copy/g,8.26×10+6、2.56×106和1.07×105copy/g,4.04×106、1.37×106和5.43×104copy/g,2.86×106、6.72×105和4.68×103copy/g,2.41×105、1.12×105和0 copy/g.除接种后21 d外,接种后各时间点A、B、C 3组的UU3浓度比较,差异均有统计学意义(P<0.05);A、B组内接种不同时间点的UU3浓度比较,差异均有统计学意义(P<0.05);C组接种不同时间点的UU3浓度比较,差异无统计学意义(P>0.05).(3)接种后7~35 d,A、B、C 3组的总致病率分别为56%(18/32)、44%(14/32)和6%(2/32),3组间比较,差异有统计学意义(P<0.01);接种后7、14、21、35 d小鼠的致病率,A组分别为5/8、5/8、4/8和4/8,B组分别为4/8、4/8、3/8和3/8,C组分别为1/8、0、1/8和0;对照组各时间点均为0.除接种后14 d外,各时间点A、B、C 3组间致病率比较,差异均无统计学意义(P>0.05).结论在小鼠生殖道局部接种不同浓度的UU3,其致病性不同.当UU3浓度≥1×106copy/g时,其致病性明显增强. 相似文献
88.
目的:研究邻苯二甲酸二丁酯(DBP)对雌性果蝇生殖能力的影响。方法:将未交配雌性果蝇随机分为5组,分别给予含DBP0.1%(A组)、0.4%(B组)、1.6%(C组)和6.4%(D组)的培养基喂饲,并以0浓度为对照组(E组),在染毒10d和20d时,分别取存活的实验雌蝇进行交配试验和生育试验。结果:各染毒组雌蝇1h交配率随DBP浓度升高而降低,D组雌蝇的1h交配率和生育率明显低于E组(P<0.05或P<0.01);染毒10d后C组的平均生育数和平均产卵期均明显高于E组(P<0.05),且在连续产卵10d后仍保持较高的生育水平;染毒20d后D组的平均生育数和平均产卵期均明显低于E组(P<0.01)。结论:DBP对雌蝇生殖能力有双重作用,较低浓度可提高雌性果蝇生育力,而较高浓度可使其生育能力降低。 相似文献
89.
目的:观察红花如意丸联合秦氏风湿灵治疗女性风湿性关节炎的临床疗效。方法:选择2012年5月—2014年9月就诊于本院的1 166例风湿痹证患者,随机分为对照组378例,治疗1组390例和治疗2组398例。对照组进行西医常规治疗,治疗1组采用秦氏风湿灵加减治疗,治疗2组在治疗1组的基础上加用红花如意丸治疗。比较三组患者临床症状、膝关节功能、实验室指标急临床疗效。结果:对照组有效率为73.02%,治疗1组有效率为84.36%,治疗2组为有效率95.23%,组间比较,差异具有统计学意义(P0.05);治疗2组晨僵时间、肿胀关节数、疼痛关节数明显低于对照组和治疗1组,Lysholm评分、Tenger评分明显高于对照组和治疗1组,差异具有统计学意义(P0.05);治疗2组血清TNF-α、IL-1β、CRP、ESR均明显低于对照组和治疗1组差异具有统计学意义(P0.05)。结论:红花如意丸联合秦氏风湿灵有助于缓解女性风湿性关节患者临床症状,改善膝关节功能,减轻炎症反应,提高临床疗效。 相似文献
90.
目的:探讨miR-27a(rs895819,A>G)多态与非吸烟女性肺癌发生的相关性。方法:采用病例-对照研究方法,使用PCR-RFLP技术检测90例非吸烟女性原发性肺癌患者和97例非吸烟女性体检者rs895819位点基因型分布频率。非条件Logistic统计分析不同基因型与肺癌发生的相关性,并分析该多态与烹饪油烟暴露的协同效应及与临床参数的相关性。结果:肺癌组rs895819 位点GG突变基因型和G等位基因频率明显高于对照组(P=0.047,P=0.016)。AG+GG基因型明显增加了非吸烟女性肺癌的发生风险(OR=1.82,95%CI=1.01~3.28,P=0.038)。肺癌组和对照组烹饪油烟暴露率分别为57%和42%,差异有统计学意义(P=0.035)。回归分析显示该多态位点与烹饪油烟无交互作用;与临床病理特征(病理类型,临床分期和淋巴结转移)均无相关性。结论:has-miR-27a rs895819 G等位基因增加了非吸烟女性肺癌发生的风险。 相似文献