昆明金钱草花的形态研究

本文对花的形态特征进行了显微结构及超显微结构的研究,详细地描述了花各部分的形态。 1.昆明金钱草花的各部分均密被腺毛。各种不同形态的腺毛在花的各部分呈有规律的分布,其细胞内均充满桔黄色的分泌物,其含量随着花的生长发育不断加多,至开花前达最高峰。 2.花萼及花冠裂片以及子房壁和花丝相连部分的内部构造均相似,紧接内外表皮的薄壁细胞内常含有桔黄色的分泌物。 3.花鲜黄色。腋出单生。花基数五。雄蕊为单体雄蕊。花粉粒在扫描电镜下外壁具有网状结构。 4.柱头似浅园盘状,在扫描电镜下此浅园盘状的柱头是由若干小碗状结构组成。子房上位。特立中央胎座。蒴果。种子多数。     

Hermansky-Pudlak syndrome type 7 (HPS-7) results from mutant dysbindin,a member of the biogenesis of lysosome-related organelles complex 1 (BLOC-1)

Hermansky-Pudlak syndrome (HPS; MIM 203300) is a genetically heterogeneous disorder characterized by oculocutaneous albinism, prolonged bleeding and pulmonary fibrosis due to abnormal vesicle trafficking to lysosomes and related organelles, such as melanosomes and platelet dense granules. In mice, at least 16 loci are associated with HPS, including sandy (sdy; ref. 7). Here we show that the sdy mutant mouse expresses no dysbindin protein owing to a deletion in the gene Dtnbp1 (encoding dysbindin) and that mutation of the human ortholog DTNBP1 causes a novel form of HPS called HPS-7. Dysbindin is a ubiquitously expressed protein that binds to alpha- and beta-dystrobrevins, components of the dystrophin-associated protein complex (DPC) in both muscle and nonmuscle cells. We also show that dysbindin is a component of the biogenesis of lysosome-related organelles complex 1 (BLOC-1; refs. 9-11), which regulates trafficking to lysosome-related organelles and includes the proteins pallidin, muted and cappuccino, which are associated with HPS in mice. These findings show that BLOC-1 is important in producing the HPS phenotype in humans, indicate that dysbindin has a role in the biogenesis of lysosome-related organelles and identify unexpected interactions between components of DPC and BLOC-1.     

大自然的报复：地球上的臭氧层正受到了CFC气体严重的破坏

1987年3月2日,在美国《新闻周刊》上曾报道过这样一篇文章内容:那是公元2037年,巴黎和费城到处张贴着预报洪水即将到来的告示,纽约市的街道水深4英尺,大部分居民已逃到内地。与此同时,巴西、印度和地中海沿岸国家都报道发生了白内障、疱疹和肝炎等流行病。接连第10年,皮癌的发病率大大增加,总数达5亿人。与此同时,旱灾也再次使美国中西部和克里米亚的小     

Efficient disruption of small asteroids by Earth's atmosphere

Accurate modelling of the interaction between the atmosphere and an incoming bolide is a complex task, but crucial to determining the fraction of small asteroids that actually hit the Earth's surface. Most semi-analytical approaches have simplified the problem by considering the impactor as a strengthless liquid-like object ('pancake' models), but recently a more realistic model has been developed that calculates motion, aerodynamic loading and ablation for each separate particle or fragment in a disrupted impactor. Here we report the results of a large number of simulations in which we use both models to develop a statistical picture of atmosphere-bolide interaction for iron and stony objects with initial diameters up to approximately 1 km. We show that the separated-fragments model predicts the total atmospheric disruption of much larger stony bodies than previously thought. In addition, our data set of >1,000 simulated impacts, combined with the known pre-atmospheric flux of asteroids with diameters less than 1 km, elucidates the flux of small bolides at the Earth's surface. We estimate that bodies >220 m in diameter will impact every 170,000 years.     

吹口哨即亮的灯

日本发明了一种吹口哨即亮的电灯。它是利用声控原理工作的,采用声音感应作开关,用电池作电源。当要开灯时,吹吹口哨,灯就自动发光;不用时,再吹口哨,灯     

浅析如何提高气相色谱仪检测器灵敏度

本文介绍了如何提高气相色谱分析试验检测器灵敏度的方法,结合针对所用的气相色谱仪的特点,总结提高检测器灵敏度的有效手段,为提高分析油中溶解气体的准确性,进一步判断充油电气设备健康水平及内部是否存在潜伏性故障提供保障。     

一种高频感应式在线连续真空检测的办法

本文对灯泡（灯管）在线连续生产过程中其内部真空度的检测,研究设计了一种高频感应式真空检测器,其工作稳定,使用寿命长,是传统检测手段的替代产品。     

阿财州妇幼保健所开展城镇社区卫生服务雏论

社区卫生服务作为实施人人享有卫生保健的一项具体措施，是目前实施医疗体制改革、发展卫生事业的一项系统工程，受到了我国政府和全社会的普遍关注。近几年来，在东南沿海发达地区已相继推行了形式多样的社区卫生服务，在保障社区人群整体健康中显示出了便捷、高效、低耗、优质、连续、综合的特点。我们民族地区由于经济文化发展的相对滞后，如何利用现有卫生事业资源开展社区卫生服务，特别是妇幼保健机构如何在社区卫生服务中发挥自身的职能优势，目前还是一个空白。本文拟对阿坝州妇幼保健所开展城镇社区卫生服务作一初浅的探讨，供参考。