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861.
采用B/S架构设计与实现了一个生物化学口试训练系统。该系统利用C#语言进行开发,底层运用SQL server 2005数据库进行数据管理。在系统需求分析的基础上,进行了总体设计和详细设计,主要包括用户注册子系统、考务管理子系统、限时考试子系统、查询成绩子系统、题库管理子系统、阅卷管理子系统等。系统实现后在2011~2012学年试用取得了较好的效果。  相似文献   
862.
This study examined the acute effects of relaxation training on salivary cortisol and salivary immunoglobulin A (sIgA). Members of age- and gender-matched undergraduate student pairs were randomly assigned to an experimental or control group. Forty-one experimental subjects were led through Abbreviated Progressive Relaxation Training (APRT) during a 1-h laboratory session; 14 control subjects merely sat quietly in the laboratory for an equal amount of time. All subjects provided pre- and post-intervention saliva samples and self-report data on state anxiety, perceived stress, and relaxation levels. Heart rate was also monitored immediately before and after APRT or quiet sitting. Results indicated that a brief relaxation exercise led to experimental subjects having significantly lower levels of post-intervention salivary cortisol (p = .036) and significantly higher levels of post-intervention sIgA concentration (p < .001) and secretion rate (p < .001) than control subjects. The data suggest that relaxation training may play a role in immunoenhancement.  相似文献   
863.
目的:探讨高仿真模拟支气管镜模拟技术在呼吸科专科医师支气管镜操作训练中的作用.方法:对20名呼吸科医生(支气管镜检查术的初学者)作为观察对象,采用美国生产的Simbionix GI Mentor Simulator高仿真模拟支气管镜操作系统进行培训.由2名熟练进行支气管镜检查术的呼吸科医生进行指导,比较培训前后在高仿真模拟支气管镜操作的速度、灵活性和准确性方面差异.结果:20名初学者均完成了支气管镜的操作培训.在模拟训练后,操作的灵活性、准确性和速度都明显提高.与训练前相比视野清晰可见时间由(30.0±2.0)%增加到(75.0±5.0)%:段支气管检查到达由(74.0±5.1)%提高到(89.3±4.0)%;通过咽喉及声门时间由(00.01.28±00.00.54)h缩短到(00.00.36± 00.00.09)h,操作用时由(00.07.27± 00.01.23)h缩短到(00.06.24± 00.00.54)h.误入食道次数由(6.0±2.0)缩短到(2.0±0.5),培训前机器给予自动评分为(30.8±6.6)分,培训后(70.8±6.6)分.结论:高仿真模拟支气管镜在初学气管镜呼吸专科医师培训中起到重要的作用.  相似文献   
864.
The main purpose of this pilot study was to investigate the possible influence of genetic polymorphisms of the hOGG1 (Ser326Cys) gene in DNA damage and repair activity by 8‐oxoguanine DNA glycosylase 1 (OGG1 enzyme) in response to 16 weeks of combined physical exercise training. Thirty‐two healthy Caucasian men (40–74 years old) were enrolled in this study. All the subjects were submitted to a training of 16 weeks of combined physical exercise. The subjects with Ser/Ser genotype were considered as wild‐type group (WTG), and Ser/Cys and Cys/Cys genotype were analysed together as mutant group (MG). We used comet assay in conjunction with formamidopyrimidine DNA glycoslyase (FPG) to analyse both strand breaks and FPG‐sensitive sites. DNA repair activity were also analysed with the comet assay technique. Our results showed no differences between DNA damage (both strand breaks and FPG‐sensitive sites) and repair activity (OGG1) between genotype groups (in the pre‐training condition). Regarding the possible influence of genotype in the response to 16 weeks of physical exercise training, the results revealed a decrease in DNA strand breaks in both groups, a decrease in FPG‐sensitive sites and an increase in total antioxidant capacity in the WTG, but no changes were found in MG. No significant changes in DNA repair activity was observed in both genotype groups with physical exercise training. This preliminary study suggests the possibility of different responses in DNA damage to the physical exercise training, considering the hOGG1 Ser326Cys polymorphism. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
865.
Reintroduction is a key approach in the conservation of endangered species. In recent decades, many reintroduction projects have been conducted for conservation purposes, but the rate of success has been low. Given the important role of gut microbiota in health and diseases, we questioned whether gut microbiota would play a crucial role in giant panda's wild‐training process. The wild procedure is when captive‐born babies live with their mothers in a wilderness enclosure and learn wilderness survival skills from their mothers. During the wild‐training process, the baby pandas undergo wilderness survival tests and regular physical examinations. Based on their performance through these tests, the top subjects (age 2–3 years old) are released into the wild while the others are translocated to captivity. After release, we tracked one released panda (Zhangxiang) and collected its fecal samples for 5 months (January 16, 2013 to March 29 2014). Here, we analyzed the Illumina HiSeq sequencing data (V4 region of 16S rRNA gene) from captive pandas (n = 24), wild‐training baby pandas (n = 8) of which 6 were released and 2 were unreleased, wild‐training mother pandas (n = 8), one released panda (Zhangxiang), and wild giant pandas (n = 18). Our results showed that the gut microbiota of wild‐training pandas is significantly different from that of wild pandas but similar to that of captive ones. The gut microbiota of the released panda Zhangxiang gradually changed to become similar to those of wild pandas after release. In addition, we identified several bacteria that were enriched in the released baby pandas before release, compared with the unreleased baby pandas. These bacteria include several known gut‐health related beneficial taxa such as Roseburia, Coprococcus, Sutterella, Dorea, and Ruminococcus. Therefore, our results suggest that certain members of the gut microbiota may be important in panda reintroduction.  相似文献   
866.
The main goal was to determine anaerobic and aerobic improvement of young soccer players after six-week high volume (HVT) or small sided games (SSG) training intervention. One hundred and one highly trained youth soccer players (16.2 ± 1.3 years) were divided into SSG (n = 51) and HVT groups (n = 50) and according to age into an under sixteen subgroup (U16), under seventeen subgroup (U17), and under nineteen subgroup (U19). The performance was assessed by Yo-Yo intermittent test, Repeated sprint ability test (RSA), and K-test before and after both training interventions. For U16 the SSG group recorded significant improvements in the K-test (0.64 ± 0.56 s; p = .04) and RSA (0.15 ± 0.43 s; p = .01). For U19 the SSG group recorded the same improvements, in the K-test (0.43 ± 0.57 s; p = .007), RSA (0.21 ± 0.22 s; p = .048), and Yo-Yo test (127.25 ± 17.87; p = .049). HVT improved aerobic performance when the Yo-Yo test was significantly better after intervention at U17 (199.00 ± 111.83 m; p = .030), U19 (88.40 ± 66.38 m; p = .049). In total, the HVT group spent 621 min (56.45 ± 5.01 min) of aerobic training and the Small sided game group spent 291 min (26.45 ± 8.61 min) of small sided games focused on aerobic performance. This study showed that both SSG and HVT training interventions were effective for aerobic improvement for the U19 category, but not for younger players. SSG was identified to be more appropriate to fitness development of soccer players.  相似文献   
867.
长江东流河道整治对长江江豚种群数量的影响   总被引:1,自引:0,他引:1  
长江江豚是生活在长江中下游的濒危水生哺乳动物,通常活动在江心洲和浅水缓滩附近。航道整治改变了鱼类栖息活动的水文环境,也给豚类生存带来负面影响。本文根据长江东流河道整治施工前和施工后各3 次野外考察资料,分析了3 种流态中江豚的数量与群结构。结果表明,该工程实施前江豚主要栖息活动在边滩的分离区,其次在洲头的分流区。工程实施后,整治江段的江豚种群数量年下降率达8. 9% 。江豚在分流区活动已消失,在分离区集群规模较小,且在流态之间移动增大。本文研究结果也提示长江江豚就地保护难度越来越大,从长江干流中把长江江豚迁入故道中是一件刻不容缓的工作。  相似文献   
868.
The rapid advances and adoption of smartphone technology presents a novel opportunity for delivering mental health interventions on a population scale. Despite multi‐sector investment along with wide‐scale advertising and availability to the general population, the evidence supporting the use of smartphone apps in the treatment of depression has not been empirically evaluated. Thus, we conducted the first meta‐analysis of smartphone apps for depressive symptoms. An electronic database search in May 2017 identified 18 eligible randomized controlled trials of 22 smartphone apps, with outcome data from 3,414 participants. Depressive symptoms were reduced significantly more from smartphone apps than control conditions (g=0.38, 95% CI: 0.24‐0.52, p<0.001), with no evidence of publication bias. Smartphone interventions had a moderate positive effect in comparison to inactive controls (g=0.56, 95% CI: 0.38‐0.74), but only a small effect in comparison to active control conditions (g=0.22, 95% CI: 0.10‐0.33). Effects from smartphone‐only interventions were greater than from interventions which incorporated other human/computerized aspects along the smartphone component, although the difference was not statistically significant. The studies of cognitive training apps had a significantly smaller effect size on depression outcomes (p=0.004) than those of apps focusing on mental health. The use of mood monitoring softwares, or interventions based on cognitive behavioral therapy, or apps incorporating aspects of mindfulness training, did not affect significantly study effect sizes. Overall, these results indicate that smartphone devices are a promising self‐management tool for depression. Future research should aim to distil which aspects of these technologies produce beneficial effects, and for which populations.  相似文献   
869.
Maximal voluntary strength of simultaneous bilateral exertion is known to be small compared to the sum of the unilateral exertions. This phenomenon is called bilateral deficit and the purpose of this study was to investigate whether it operates in both upper and lower limbs. A group of 7 female and 32 male students were divided into 4 training groups and a control group. The unilateral arm or leg training group performed maximal isokinetic arm or leg extensions using each arm or leg unilaterally. The bilateral arm or leg training group trained using bilateral extensions of both arms or legs. The groups in training continued these two types of resistance exercise 3 days a week, for 6 weeks. The control subjects did not train. The improvement in power brought about by training was compared from the viewpoint of whether the limbs (arms or legs) were trained or not and whether the mode of test power exertion (bilateral or unilateral) was the same as performed during training or not. The power in the trained limbs using the same regime as that during training (3.0% after 3 weeks, 7.7% after 6 weeks) showed the largest improvement ratio. This agrees with the specificity theory in resistance training. The increase in power in untrained limbs using the same regime as during training (2.1% after 3 weeks, 3.5% after 6 weeks; P < 0.01) and the increase in power in the untrained limbs after the opposing mode of training (1.2% after 3 weeks, 2.2% after 6 weeks; P < 0.05) were larger than that of the controls (−2.5% after 3 weeks, −1.1% after 6 weeks). This suggests that the effect of resistance training was transferred to the untrained limbs (i.e. to the legs in the arm training group and to the arms in the leg training group). The degree of bilateral deficit (bilateral index, BI) in the trained limbs of the bilateral training group was shifted in a positive direction (4.2% after 3 weeks, 3.7% after 6 weeks) and that in the trained limbs of unilateral training group was shifted in a negative direction (−3.0% after 3 weeks, −5.4% after 6 weeks) by 6 weeks of training. The BI in the untrained limbs of the unilateral training group was shifted in a negative direction (−1.9% after 3 weeks, −4.5% after 6 weeks) by 6 weeks of training, whereas that in the untrained limbs of the bilateral training group was not shifted in a positive direction (−0.1% after 3 weeks, −2.4% after 6 weeks). These results would suggest that bilateral deficits in the upper and lower limbs are at least partially affected by some common mechanism at a supraspinal level. Accepted: 3 March 1998  相似文献   
870.
Abstract

Aim of the study: To investigate a more available model for the early phase of motor learning after action observation combined with motor imagery training in elderly people. To address the purpose, we focused on a slow, unskilled model demonstrating an occasional error.

Materials and methods: A total of 36 elderly people participated in the current study and were assigned to either the unskilled or skilled model observation groups (n?=?12, respectively), or the control group (n?=?12). The participants in the observation groups observed the assigned a video clip of an unskilled or skilled model demonstrating a ball rotation task. During the observation, the participants were instructed to imagine themselves as the person in the video clip. The participants in the control group read a scientific paper during the equivalent period of action observation and motor imagery. We measured ball rotation performance (the time required for five rotations, the number of ball drops) in pre- and post-intervention (observation combined with motor imagery training for intervention groups or reading for control group).

Results: Ball rotation performance (ball rotation speed) significantly improved in the unskilled model observation group compared to the other two groups.

Conclusions: Intervention for action observation using unskilled model combined with motor imagery was effective for improving motor performance during the early phase of motor learning.  相似文献   
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