等速离心训练对肩关节内外旋肌的肌力平衡及神经肌肉控制能力的影响

背景 肩关节内外旋肌肌力失衡会增加肩部运动损伤的风险,研究等速离心训练(IET)能否提高肌力平衡并改善神经肌肉控制能力具有重要的损伤预防意义。目的 探讨IET对健康青年人肩关节内外旋肌的肌力平衡及神经肌肉控制能力的影响。方法 2020年12月至2021年11月在复旦大学附属中山医院招募32例健康青年志愿者为研究对象,随机将其分为试验组(n=16)和对照组(n=16)。试验组接受4周IET,对照组接受4周连续被动运动训练(2次/周)。采用Biodex System 4 Pro多关节等速肌力测试与训练系统(美国Biodex公司)对两组研究对象的优势侧肩关节内、外旋肌群进行训练干预,分别在60(°)/s、120(°)/s速度下进行,干预前1周、干预结束后1周对两组肩关节内外旋肌的功能性比率(FR)、加速时间(AT)和达峰力矩时间(TPT)进行评估并比较。结果 试验组全部完成了4周的训练干预和评估,对照组2例中途退出。最终共30例研究对象数据纳入统计学分析。在60(°)/s和120(°)/s速度下,试验组干预后FR高于对照组(P<0.001),试验组干预后FR高于干预前(配对t检验：t<...     

Five different tests of reaction time evaluated in HIV seropositive men

In an attempt to develop a short neuropsychological test battery five different tests of reaction time were assessed according to their ability to discriminate between HIV seropositive men and healthy controls. In all tests a patient group with clinical symptoms was slower than the control group. In the complex reaction time test, which has a large cognitive aspect, even a clinically "asymptomatic" group was slower than the control group. The movement test, a new test with a large motor component, identified most slow responders, defining approximately half of the patients with clinical symptoms and one third of the "asymptomatic" patients as such. A test battery consisting of three tests is suggested for serial assessment and screening.     

The effects of clonidine and yohimbine on human information processing

The effects of clonidine and yohimbine on human information processing were tested in six normal volunteers ages 18–30 years. Subjects were tested in a pre-post design with sessions conducted at weekly intervals. Three drug conditions were: Placebo (lactose), 0.2 mg clonidine, and 30 mg yohimbine. Two choice reaction time (RT) tasks were used. One was a stimulus evaluation-response selection task (SERS) that has been shown to be sensitive tod-amphetamine, methylphenidate and scopolamine. The other task was to assess stimulus pre-processing and used spatial frequency as a discriminative stimulus. The principle finding was that clonidine slowed RT; this effect was significant for both tasks. In contrast, yohimbine tended to speed RT, but the effects were significant only for the spatial frequency task on some analyses while not for others. RTs to high spatial frequency stimuli were speeded more than for low spatial frequency. The effects of these two NE drugs were compared with findings withd-amphetamine and scopolamine and interpreted within the framework of a serial information processing model proposed by Callaway (1983). Specifically, it is suggested that yohimbine and clonidine affect an early pre-processing stage.     

Intramuscular pressure,EMG and blood flow during low-level prolonged static contraction in man

Seven men performed one-legged isometric knee-extension at 5% MVC for 1 h. Intramuscular pressure increased with contraction from its resting value of 14 (2–31) mmHg. Some intramuscular pressure recordings stayed at an almost constant level throught the 1 h contraction, but most recordings showed large fluctuations from resting values up to 90 mmHg. The overall mean intramuscular pressure was twice the resting value. In some cases, EMG recordings confirmed that the changes in intramuscular pressure were related to alternating recruitment of various parts of the knee-extensors. Blood flow in the femoral vein increased within 3 min of 5% MVC to a level of 1.58 (1.25-2.22) 1 min^-1 and no significant changes occurred during the 1 h contraction. In two subjects blood flow was measured also in the recovery period, and this decreased almost immediately when the muscle relaxed. It is concluded that during low-level static contractions, the blood supply to the exercising muscle is maintained at a sufficiently high level, and that the alternating recruitment of muscle fibres may result in a heterogeneously distributed blood flow within the contracting muscle. Despite this the muscle was fatigued after the 1 h at 5 % MVC. The rating of perceived exertion (RPE) increased from 1.9 (1–3) at the beginning to 4.5(2–8) at the end of contraction, and MVC was decreased by 12% after the contraction.     

Effects of infrasound on the Rota-Rod Treadmill performance of rats

Summary The present study was designed to evaluate the effects of infrasound on behavioral performance in rats. The rats were divided into two groups, one selected for good performance (six rats: superior group) and the other for poor performance (six rats: inferior group) on the Rota-Rod Treadmill.Exposure conditions were as follows:Exp. 1 Control (150 min), Exp. 2 Exposure to infrasound with a main frequency of 16 Hz and a sound pressure level of 105 dB (S.P.L.) (70 min), Exp. 3 Exposure to infrasound with a main frequency of 16 Hz and a sound pressure level of 95 dB (S.P.L.) (70 min), Exp. 4 Exposure to infrasound with a main frequency of 16 Hz and a sound pressure level of 85 dB (S.P.L.) (150 min), Exp. 5 Exposure to infrasound with a main frequency of 16 Hz and a sound pressure level of 75 dB (S.P.L.) (150 min), Exp. 6 Exposure to Pink Noise of 72 dB (A) (70 min).Comparison of the pre-exposure endurance time (Maximum: 2 min) on the Rota-Rod Treadmill with endurance after exposure to infrasound showed that the endurance time of the superior group after exposure to 16 Hz, 105 dB was not reduced. The endurance of the inferior group was reduced by exposure to 16 Hz, 105 dB after 10 min, to 16 Hz, 95 dB after 70 min, and to 16 Hz, 85 dB after 150 min.     

Effect of tissue fixatives on telomere length determination by quantitative PCR

Telomere length is a well established marker of cellular senescence and thus biological age. Quantitative PCR allows the determination even from very low amounts of tissue by using telomere specific and single copy gene primers. Comparing a directly processed tissue sample to a 4% formaldehyde fixed one showed a significantly reduced efficiency of PCR reactions (mainly in single copy gene experiments) in a storage time-dependent manner resulting in an artificial increase in reported relative telomere length. This effect was not seen when the tissue was stored in RNA later solution. In summary, telomere length determination from formaldehyde fixed material by quantitative PCR is not a reliable method. Unfortunately therefore, many easily accessible tissue samples from pathology laboratories are unsuitable for this technique.     

Rapid identification of female carriers of DMD/BMD by quantitative real-time PCR

Recently developed PCR systems offer online-monitoring of amplification and allow simple and reliable DNA quantification. We have used the LightCycler system to develop a simple and rapid method for direct identification of female carriers of deletions and duplications in the dystrophin gene. The challenge resides in the ability to identify the presence of a deleted or duplicated allele over the background contributed by the normal allele. Quantification is based on the determination of the ratio between potentially deleted/duplicated dystrophin exons and non-deleted/-duplicated reference exons using the unspecific dsDNA-dye SYBRgreen I. In a retrospective study, we evaluated our method in female relatives of DMD/BMD patients with known carrier status by comparative analysis of deleted or duplicated versus non-deleted/-duplicated exons. Carrier status was accurately attributed in 100% of cases, the mean ratios being 0.52+/-0.12 for deletion carriers (expected value: 0.5) and 1.56+/-0.18 for duplication carriers (expected value: 1.5) vs. 1.022+/-0.17 for non-carriers (expected value: 1.0). The method proved to be simple, rapid, reliable, and cost-effective. It may be used for direct determination of deletions/duplications in potential DMD/BMD carriers and may easily be adapted for other genetic conditions involving deletions and duplications.     

Diverging prevalence trends of atopic disorders in Norwegian children. Results from three cross-sectional studies

BACKGROUND: During the last decades there has been extensive epidemiological research to explore the increasing prevalence of asthma and allergy in childhood. The worldwide variations in prevalence of these diseases necessitate regional rapports. Furthermore, time-trend analyses with comparable methods are important in order to monitor the rapidly changing prevalence of these diseases. METHODS: Three cross-sectional questionnaire-based studies of asthma and allergy in schoolchildren were conducted in the counties of Troms and Finnmark, in northern Norway in 1985, 1995 and 2000. The two former studies included children from randomly selected primary schools (n = 1794/1985, n = 1432/1995). The latter study was a part of ISAAC-II Europe study (n = 3853). Identical items of asthma and allergy were employed. The analyses comprised only children 9-11 years of age. RESULTS: The prevalence of asthma was 9.3, 13.2 and 13.8% in 1985, 1995 and 2000, respectively. However, great gender differences were detected; the prevalence of asthma increased in males from 1995 to 2000, from 14.1 to 17.0%, RR = 1.2 (95% CI 1.0-1.5), but decreased in females 1995 to 2000, from 12.3 to 10.5%, RR = 0.9 (95% CI 0.7-1.1). Furthermore, in children with asthma, a changing trend was found in the external factors that perceived symptoms, from typical allergens towards other, unspecific agents. The prevalence of self-reported atopic eczema/dermatitis syndrome (AEDS) was 13.4, 21.1 and 20.8% in 1985, 1995 and 2000, respectively. The prevalence of self-reported allergic rhinoconjunctivitis was in 16.5, 24.7 and 29.6% 1985, 1995 and 2000, respectively, RR (2000/1995) = 1.2 (95% CI 1.1-1.3). CONCLUSION: The prevalence of asthma in girls has reached a plateau and even decreased from 1995 to 2000 which is in contrast to the asthma prevalence in boys that tends to continuously increase. The prevalence of AEDS which increased substantially between 1985 and 1995 did not change from 1995 to 2000. However, the prevalence of allergic rhinoconjunctivitis increased steadily from 1985, 1995 to 2000.     

3-7岁麻烦型气质儿童餐桌行为的心理干预

目的：探讨心理干预对3－7岁麻烦型气质儿童的餐桌行为的作用。方法：用CTPS（China Preschool-children Temperament Scale)问卷方式对410名3－7岁儿童的气质类型进行综合评定划分出5个气质类型；对其中50名麻烦型气质儿童的餐桌行为问题进行了3个月的心理干预治疗。并对其餐桌行为做干预前后的偏挑食行为，改善进餐情绪，提高进餐速度有效。结论：心理干预可以纠正儿童的餐桌行为。     

215例急性和亚急性重型肝炎临床特征对比性分析

目的进一步了解急性重型和亚急性重型肝炎（简称急重和亚急重）患者的临床特征，以及它们之间的异同。方法收集和整理215例急重和亚急重住院患者的临床资料，使用X^2检验、t检验、回归分析等方法进行相关的统计学分析。结果①乙型肝炎病毒感染仍是急重和亚急重型肝炎的主要病因，均占30％以上。抗结核药物是药物性急重和亚急重肝炎的首要原因；②急重和亚急重患者肝性脑病发生率分别为78．13％和43．05％，差异有统计学意义（P〈0．001）；③急重患者的平均凝血酶原活动度低于20％，而亚急重患者平均凝血酶原活动度低于30％；④急重患者发生率前三位的并发症分别为肝性脑病、电解质紊乱及脑水肿；而亚急重则分别为腹水、电解质紊乱及肝性脑病；⑤急重和亚急重患者的病死率与病情最重时PT、WBC及中性粒细胞比例均呈正相关，而与PTA、TC均呈负相关；亚急重还与病情最重时TB、BLA及CRE呈正相关，与CHE、TG、PLT、ALB呈负相关。结论①急重和亚急重患者无论在好发年龄、肝性脑病发生率、肝性脑病出现时间，还是在凝血功能异常、预后与实验室指标等方面差异较大，属两个独立的疾病；②对于无肝性脑病的急重和亚急重患者，严重的凝血功能异常是一个重要的灵敏和特异性指标。