大鼠阴道上皮细胞对白色念珠菌生长抑制作用的初探

目的研究阴道上皮细胞对白色念珠菌生长的影响。方法以雌性SD大鼠动情间期阴道上皮细胞作为效应细胞,白色念珠菌芽生孢子作为靶细胞,将效靶细胞共同孵育8h,观察念珠菌生长密度,检测念珠菌摄取3H-葡萄糖的能力,电镜观察其超微结构的改变。结果阴道上皮细胞与白色念珠菌细胞共同孵育后,念珠菌生长密度降低;效靶细胞比例为40:1,20:1,10:1,1:1时,念珠菌摄糖抑制率分别为52.34%,32.56%,28.73%,18.46%;电镜观察,单独培养的白色念珠菌结构完整,细胞壁、细胞膜及细胞器结构清晰,而与阴道细胞共孵育后的白色念珠菌细胞壁溶解破坏,细胞膜连续性破坏,细胞器肿胀溶解。结论大鼠阴道上皮细胞对白色念珠菌具有天然的生长抑制作用。     

土酸介质中锌单组分缓蚀剂的筛选

选取了数十种化合物,用失重法分别对其在土酸溶液中对锌的缓蚀性能进行了研究,结果发现在土酸介质中对锌起缓蚀作用的化合物主要是季铵盐类(苯扎溴胺、十六烷基三甲基溴化铵)、杂环化合物(溴代十六烷基吡啶)和含硫化合物(十二烷基磺酸钠)等。     

递增负荷运动过程中雌性大鼠生殖激素水平的变化特点及其机制

对递增负荷运动过程中及恢复期大鼠HPG轴功能激素水平进行了连续、系统的动态观察。结果表明，在长期持续大负荷训练影响下，HPG轴功能全面受抑，激素水平降低，以低促性腺激素及低性腺类固醇水平为特征；恢复期HPG轴功能呈现逐渐恢复态势。     

Contralateral limb deficit after ACL-reconstruction: an analysis of early and late phase of rate of force development

The aim of this study was to assess the effect of a unilateral anterior cruciate ligament reconstruction (ACLR) on maximum voluntary contraction (MVC) and explosive strength of both the involved limb and the uninvolved limb. Nineteen male athletes completed a standard isometric testing protocol 4 months post-ACLR, while 16 healthy participants served as a control group (CG). The explosive strength of the knee extensors and flexors was assessed as RFD obtained from the slope of the force–time curves over various time intervals. Both muscle groups of the involved limb had significantly lower MVC compared to the uninvolved. The involved limb also had significantly lower RFD in the late phase of contraction (140–250 ms) for both knee extensors and flexors (P < 0.05). There was no difference in MVC between the uninvolved limb and the CG. However, RFD of the uninvolved limb was lower compared to CG for both knee extensors (0–180 ms; P < 0.01) and flexors (0–150 ms; P < 0.05). ACLR leads to lower MVC and explosive strength of the involved limb. As a consequence of potential crossover (presumably neural-mediated) effects, explosive strength deficits could be bilateral, particularly in the early phase of the contraction (<100 ms).     

黄芩苷对小鼠抗炎作用的研究

昆明种小鼠100只随机均分10组：分别为口服和腹腔注射黄芩苷制剂大（2．0g／kg）、中（1．og／kg）、小（0．5g／kg）剂量组、阳性对照组（口服和腹腔注射地塞米松注射液0．01g／kg）和空白对照组（口服和腹腔注射等量生理盐水）,每天给药1次,连续给药7d,最后一次给药后30min,用二甲苯致小鼠耳廓肿胀,致炎1h后颈椎脱臼致死,冲下左右两耳片分别称重,测定小鼠耳廓的肿胀率和肿胀抑制率。结果：与生理盐水对照组比较,口服黄芩苷大剂量组小鼠耳廓的肿胀率显著降低（P〈0．01）;腹腔注射黄芩苷大剂量组小鼠耳廓肿胀率显著降低（P〈0．01）,中、小剂量组肿胀率降低（P〈0．05）。表明黄芩苷口服或腹腔注射对小鼠均具有一定的抗炎作用,呈现量效关系,且腹腔注射抗炎效果强于口服。     

高速电路PCB设计中串扰问题的抑制

在电子产品设计的高速化和小型化时代,如何抑制传输信号的串扰,使其降低到最低,这是每一位高速电路PCB设计者,所要追求的目标。本文通过对影响传输信号串扰因素的分析,结合多年高速电路PCB设计的经验,对抑制信号串扰的方法做了比较详尽的表述。为高速电路PCB设计人员提供一些经验,使得在高速电路PCB设计中少走弯路。     

微乳盐酸体系的制备及性能研究

以煤油、盐酸、表面活性剂和助表面活性剂为主要原料,制备了稳定的微乳盐酸体系。通过正交试验得到该体系的最优乳化剂配方,当乳化剂在最优配比条件下,可得到较大的单相区面积。测试了微乳酸体系的粒径分布,考察了微乳酸体系的耐温、耐盐能力。结果表明,该微乳酸体系粒径小,平均粒径为仅27．5nm,且具有良好的耐温性,耐CaCl2能力可以达到70000mg/L。与相同浓度盐酸相比,微乳盐酸体系的缓速效果显著。     

Hamstring muscles’ function deficit during overground sprinting in track and field athletes with a history of strain injury

ABSTRACT

In this study, we aimed to clarify the characteristics of neuromuscular function, kinetics, and kinematics of the lower extremity during sprinting in track and field athletes with a history of strain injury. Ten male college sprinters with a history of unilateral hamstring injury performed maximum effort sprint on an athletic track. The electromyographic (EMG) activity of the long head of the biceps femoris (BFlh) and gluteus maximus (Gmax) muscles and three-dimensional kinematic data were recorded. Bilateral comparisons were performed for the EMG activities, pelvic anterior tilt angle, hip and knee joint angles and torques, and the musculotendon length of BFlh. The activity of BFlh in the previously injured limb was significantly lower than that in the uninjured limb during the late-swing phase of sprinting (p < 0.05). However, the EMG activity of Gmax was not significantly different between the previously injured and uninjured limbs. Furthermore, during the late-swing phase, a significantly more flexed knee angle (p < 0.05) and a decrease in BFlh muscle length (p < 0.05) were noted in the injured limb. It was concluded that previously injured hamstring muscles demonstrate functional deficits during the late swing phase of sprinting in comparison with the uninjured contralateral muscles.     

The Learning Advantages of an External Focus of Attention in Golf

Abstract

Two unique methodological strategies were used to investigate the influence of retroactive inhibition on recall within a contextual interference paradigm. Three independent blocked groups, blocked without retroactive inhibition (BL-without), blocked with 18 trials of retroactive inhibition (BL-18), and blocked with 36 trials of retroactive inhibition (BL-36), were created that varied in order of presentation of tasks. By testing a single task in retention and creating three independent blocked groups, varying amounts of retroactive inhibition were produced. This isolated the effects of retroactive inhibition on blocked compared to control and random subjects' retention. The Acquisition Group x Retention Trials interaction indicated that random and BL-without subjects had shorter reaction time than BL-18 and BL-36 subjects. Thus, blocked subjects with retroactive inhibition exhibited a retention deficit compared to BL-without subjects. The results support previous contextual interference findings and suggest that retroactive inhibition influences the retention deficits demonstrated by blocked compared to random subjects in typical contextual interference investigations.     

求偶抑制记忆对果蝇攻击性的影响

求偶抑制记忆可以减少雄果蝇(Drosophila melanogaster)对处女蝇的求偶行为,并且这种记忆属于长时间记忆.目前有关求偶抑制记忆对果蝇攻击行为影响的研究一直很缺乏.研究中,以野生型果蝇CS株作为实验对象,通过数字摄像机对果蝇行为进行记录,然后根据录像对果蝇潜伏期及头撞次数两种行为学指标进行统计分析,最后通过t检验分析得出求偶抑制记忆是否对果蝇攻击性造成影响的结论.结果表明,求偶抑制记忆可以延长雄果蝇在争夺交配权时的潜伏期,但对争夺食物时的潜伏期却无明显影响.同时,求偶抑制记忆对争夺交配权时和争夺食物时的头撞次数均无明显影响.推断求偶抑制记忆特异的作用于争夺交配权时的潜伏期,从而使果蝇打斗潜伏期延长,攻击性减弱.在打斗开始之后发生的攻击行为可以部分消除求偶抑制记忆对果蝇的影响,使果蝇部分的恢复攻击能力.