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1.
中药材绵萆解的主要原植物，经与采自日本的七裂叶萆解Dioscorea septemloba Thunb．     相对照，认为系一新种Dioscorea spongiosa J．Q.Xi，M. Mizuno et W．L．Zhao。该二种主要     区别如下：1．绵萆解地下茎直径3—6cm，色枯黄至黑棕; 叶微波缘或全缘，罕掌裂; 蒴果扁球     形，种翅矩圆形，紫红色。七裂叶萆解地下茎直径1—2cm，色枯黄; 叶全为掌裂; 蒴果倒卵     状; 种翅倒卵形，灰棕色。2．绵萆解花粉粒外壁纹饰肋条状，在七裂叶萆解为网状。3．绵萆解地下茎中柱鞘有众多石细胞，在七裂叶萆解则未见石细胞。4．地下茎甾体皂甙元硅胶G     板层析，以苯：乙酸乙酯：石油醚(4：1：1)展开，磷钼酸显色，二者均现6斑点，绵萆解的第5点     面积和第6点Rf值均较七裂叶萆解大。  5．地下茎甾体皂甙元的紫外光谱检测，绵萆解在399nm处有峰，363有谷; 七裂叶萆解在310有峰，250有谷。  相似文献   
2.
Many girls are not sent to school in Yemen, despite basic education being free as well as compulsory for all children aged 6–15. Aiming to improve girls’ enrolment by increasing parental and community involvement, the Japan International Cooperation Agency (JICA) offered a technical cooperation project in June 2005 called Broadening Regional Initiative for Developing Girls’ Education (BRIDGE). Phase 1 of this project ran for three and a half years, piloting a participatory school management model supported by school grants in six districts of the Taiz Governorate in the Southwest of Yemen. To find out how successful this approach has been in a traditional society, the authors of this paper analysed the gender parity index (GPI) of the project’s pilot schools. Based on data collected at three points in time (in the initial and final years of the project, and two years after the project’s end), their findings suggest that interventions in school management which strongly emphasise girls’ education can be effective in improving gender parity rather quickly, regardless of the schools’ initial conditions. However, the authors also observe that the pilot schools’ post-project performance in terms of gender parity is mixed. While the local government allocated budgets for school grants to all pilot schools even after the project’s end, training and monitoring activities were cut back. The authors further observe that the variation in performance appears to be significantly correlated with school leaders’ initial perceptions of gender equality and with the number of female teachers employed. These findings point to the importance of providing schools with continuous long-term guidance and of monitoring those which implement school improvement programmes.  相似文献   
3.
Aim: Recent meta-analyses of the literature confirmed the association between the RR+RX genotype of the ACTN3 R577X polymorphism and elite sprint/power athletic status in Europeans but not in Asians and Africans, while the association between the R577X genotype and elite endurance athlete status is less convincing. The aim of the present study was to investigate the association between the ACTN3 R577X genotype and elite athlete status in a large Asian (Japanese) cohort of track and field athletes. Methods: One-thousand fifty-seven Japanese track and field athletes (627 sprint/power athletes and 430 endurance athletes) and 810 Japanese controls were genotyped for the ACTN3 R577X polymorphism (rs1815739) by using the TaqMan® SNP Genotyping Assay. Results: Elite sprint/power athletes had a higher frequency of the RR+RX genotype than the controls (OR: 1.59, 95% CI: 1.16–2.18; P?=?.003). A significant linear correlation was found between the RR?+?RX genotype and athlete status (i.e. regional?P?=?.001 for trend) and long-distance runners (regional: 65%, national: 72%, international: 82%; P?=?.030 for trend). Conclusions: The data obtained for this large Asian (Japanese) cohort of track and field athletes served to confirm the association between the RR?+?RX genotype of the ACTN3 R577X polymorphism and elite sprint/power athlete status and also the association between the ACTN3 RR?+?RX genotype and long-distance running athletic status.  相似文献   
4.
Osteopenia is a condition in which bone mineral density (BMD) is lower than normal. Exercise increases BMD in both the young and adults. This study aimed to compare the radial apparent BMD (aBMD) in Japanese females who are Kendo practitioners (KPs) and those with no regular exercise habits (no-REH). The analysis participants consisted of 45 KPs (mean age: 49.4 years old) and 110 no-REH (mean age: 48.8 years old). Radial aBMD was measured using an ultrasonic bone densitometry system. Radial aBMD in KPs was 196.1 ± 33.9 mg/cm3, and was 182.9 ± 45.3 mg/cm3 in no-REH participants. KPs had significantly higher BMD than no-REH participants. In KPs, left radial aBMD was 196.1 ± 33.9 mg/cm3, and right radial aBMD was 184.5 ± 37.7 mg/cm3. The left radius was also significantly higher than the right radius with respect to aBMD in KPs. After adjusting for age, body mass index, menstrual status, parous women and frequency of milk and dairy intake, the odds ratio (OR) of osteopenia associated with no-REH was 6.58 (95% confidence interval (CI): 1.72–25.1) and the prevalence ratio (PR) of osteopenia associated with no-REH was 4.12 (95% CI: 1.23–13.7). Therefore, the Kendo practice may have a protective efficacy for osteopenia in women.  相似文献   
5.
本文着重讨论山豆根属植物的分类、分布、系统亲缘及起源等问题。对本属的分类历史和”山豆 根”一名的由来作了回顾和考证．按中国古典植物文献，”山豆根’指的是Euchresta japonica 。     我们对山豆根属进行一次清理，在本文共报道4种3变种，其中发现一新变种——短管山豆根 Ｅ.tubulosa Dunn var.brevituba C.Chen，井以萼管的有无建立I.山豆根组sect．I．Euchrestae(3种1变 种)及II．管萼组sect．II．Tubulosae(1种2变种)。     山豆根属的现代分布中心在我国中部及南部，可能是第三纪或略早一些的古热带山地森林植物区 系的成员。推测本属可能出现于晚白垩纪，可能是华夏起源。本属的分布区正好处于 “华莱士线”的西 侧，从古地理的资料告诉我们大约在五千万年前，新几内亚和澳大利亚还处在向北移动的状态，这时本 属已遍布东亚和东南亚地区，因此，新几内亚和澳大利亚等地没有本属的分布，这一分布格局正好又一 次证明，在这一地区的诸多的生物地理分界线中，”华莱士线’更符合自然，使我们更清楚的认识到”华莱 士线”的实际意义不仅是劳亚古陆与冈瓦纳古陆的分界线，而且还是亚洲与澳大利亚地区劳亚古陆植物区系与冈瓦纳古陆植物区系的分界线。  相似文献   
6.
Hydrogels have several excellent characteristics suitable for biomedical use such as softness, biological inertness and solute permeability. Hence, integrating hydrogels into microfluidic devices is a promising approach for providing additional functions such as biocompatibility and porosity, to microfluidic devices. However, the poor mechanical strength of hydrogels has severely limited device design and fabrication. A tetra-poly(ethylene glycol) (tetra-PEG) hydrogel synthesized recently has high mechanical strength and is expected to overcome such a limitation. In this research, we have comprehensively studied the implementation of tetra-PEG gel into microfluidic device technology. First, the fabrication of tetra-PEG gel/PDMS hybrid microchannels was established by developing a simple and robust bonding technique. Second, some fundamental features of tetra-PEG gel/PDMS hybrid microchannels, particularly fluid flow and mass transfer, were studied. Finally, to demonstrate the unique application of tetra-PEG-gel-integrated microfluidic devices, the generation of patterned chemical modulation with the maximum concentration gradient: 10% per 20 μm in a hydrogel was performed. The techniques developed in this study are expected to provide fundamental and beneficial methods of developing various microfluidic devices for life science and biomedical applications.  相似文献   
7.
The purpose of this study was to examine the effects of varying amounts of dynamic stretching (DS) on joint range of motion (ROM) and stiffness of the muscle–tendon unit (MTU). Fifteen healthy participants participated in four randomly ordered experimental trials, which involved one (DS1), four (DS4) and seven (DS7) sets of DS, or control conditions/seated at rest (CON). Each DS set consisted of 15 repetitions of an ankle dorsiflexion–plantarflexion movement. The displacement of the muscle–tendon junction (MTJ) was measured using ultrasonography while the ankle was passively dorsiflexed at 0.0174 rad · s?1 to its maximal dorsiflexion angle. Passive torque was also measured using an isokinetic dynamometer. Ankle ROM was significantly increased after DS4 and DS7 compared with the pre-intervention values (P < 0.05), but there were no significant differences in ankle ROM between DS4 and DS7. No differences were observed in ankle ROM after DS1 and CON. In addition, the stiffness of the MTU, passive torque and displacement of the MTJ at submaximal dorsiflexion angles did not change in any of the experimental conditions. These results indicate that DS4 increased ankle ROM without changing the mechanical properties of the MTU, and that this increase in ankle ROM plateaued after DS4.  相似文献   
8.
While there is a growing presence of trans-Pacific migrant students in the US, relatively little attention has been given to the diversity among them in terms of their everyday experiences and future educational trajectories shaped by different patterns of transnational mobilities and practices. This paper addresses the distinctive educational experiences and needs of transnational Japanese students, temporarily enrolled in US schools accompanying their parents on business appointments from transnational corporations. This institutional ethnographic study examines the strategies that these sojourner students use to negotiate the institutional demands of US high-school life and the way to promote access to tertiary education in Japan. The findings show that, although corporate transnationalism restricts Japanese sojourners' geographical mobility, they still actively construct their futures through the high-stakes strategy of graduating a year early from US high schools. I call this early graduation scheme a gambit because the sojourners sacrifice beneficial opportunities and even risk their graduation itself in the hope of securing a positional advantage upon their return to their home country. The early graduation gambit is analysed through a lens of transnationalism.  相似文献   
9.
This study evaluated the association between the frequency of tennis play and executive function in children and adolescents. One hundred and six junior tennis players (6–15 years old) participated in this study. Executive function, including inhibitory control, working memory, and cognitive flexibility were evaluated at rest. Females showed better inhibitory control and cognitive flexibility than males. In males, more frequent tennis play was associated with higher basic processing speed and inhibitory control after controlling for age, gender, body mass index (BMI), and tennis experience. More frequent tennis play was associated with better working memory in both males and females after controlling for age, gender, BMI, and tennis experience. Furthermore, longer tennis experience was related to better cognitive flexibility in males after controlling for age, gender, BMI, and frequency of tennis play. These findings suggest that tennis play is associated with the development of three foundational aspects of executive function (i.e. inhibitory control, working memory, cognitive flexibility). Especially, frequent participation in tennis play is related to better inhibitory control and working memory, while longer experience of tennis play is associated with better cognitive flexibility. Although development of inhibitory control and cognitive flexibility is slower in males than in females, the associations between tennis play and inhibitory control and cognitive flexibility appear to be larger in males than in females.  相似文献   
10.
The aim of this cross-sectional study was to evaluate the relationships between cognitively engaging exercise (i.e., game-based and coordination exercises), executive functions (i.e., inhibitory control and working memory), and physical fitness. Forty junior tennis players (6–12 years old), who regularly participated in tennis lessons (2.55 years, SD = 1.61) prior to the study, were investigated. All participants completed evaluations of executive functions (inhibitory control and working memory) at rest. The duration of each lessons’ instructional activities, including coordination training, game-based exercise, rallying, and non-physical activity (explanations and breaks), was recorded. Physical fitness was evaluated using the Tennis Field Test. A longer duration of game-based exercise was positively correlated with inhibitory control and physical fitness. Coordination training was associated with improved working memory. Non-physical activity was inversely correlated with inhibitory control, working memory, and physical fitness. The results suggest that game-based tennis lessons have beneficial effects on inhibitory control and physical fitness levels, and a longer duration of coordination training is associated with better working memory. The present study indicates that shortened non-physical activity time within a sports setting is associated with the development of executive functions and physical fitness.  相似文献   
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