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961.
Teens' own thoughts on fostering safe sexual practice are important perspectives in promoting adolescent sexual health yet are relatively absent in the literature. This focus group study explored teens' perceptions about the supports and challenges that exist as teens strive to engage in healthy sexual practices. Seventy-five teens participated in 11 focus groups using a semi-structured interview guide. School-based health centers provided the setting and facilitated sample recruitment. Focus groups were audiorecorded and transcribed verbatim. Data were analyzed using the focus group guide as a template and typologies, or clusters of concepts, were extracted to establish teen perceptions of the factors that support and challenge their ability to engage in safe sexual practices. The socio-ecological model provided the framework to identify these factors within the individual, family/parent, relational (peer/partner), community, or societal spheres of influence. Results discussed the importance of parents, the value of confidentiality, respect for teen decision-making, relationships skills, developmental aspects of the adolescent years, and social interpretations of gender. These findings revealed important considerations as adults develop policies, messages, and programs designed to promote safe sexual behavior in teens.  相似文献   
962.
Efficient lysis is critical when analyzing single cells in microfluidic droplets, but existing methods utilize detergents that can interfere with the assays to be performed. We demonstrate robust cell lysis without the use of detergents or other chemicals. In our method, cells are exposed to electric field immediately before encapsulation in droplets, resulting in cell lysis. We characterize lysis efficiency as a function of control parameters and demonstrate compatibility with enzymatic assays by measuring the catalysis of β-glucosidase, an important cellulase used in the conversion of biomass to biofuel. Our method enables assays in microfluidic droplets that are incompatible with detergents.  相似文献   
963.
住宅输电线是世界上分布最广泛的网络,无处不在的家庭电源插座即将成为人们进入互联网世界的大门,期盼通过电线,将PC、电话、音响甚至电冰箱都能连成一气,统统连上网络,彼此沟通,而无需大费周折另外布线!要完全不出错,通过电源线进行讯号处理的复杂程度远远超过之前采用的任何技术.  相似文献   
964.
科学与怪异     
近几十年来,世界上出版了许多奇谈怪论的书,它们披着科学的外衣,实际上是在宣传神灵、迷信与伪科学。……其主要内容不外是外星人已经访问过地球、上帝是宇航员、百慕大三角、飞碟、天外来客、通灵人等等。在这种情况下,美国的一批著名学者,如乔治·O·阿贝尔、艾萨克·阿西奠夫、卡尔·萨根和马丁·加德纳等,为广大读者编写了这本《科学与怪异》。他们在书中首次就一些超自然现象进行了科学的分析。  相似文献   
965.
966.
Allergenic/antigenic proteins are known to induce Type I and Type III hypersensitivity reactions leading to allergic bronchopulmonary aspergillosis (ABPA) in immunocompetent host. The common structural features or intrinsic properties of the allergens/antigens leading to allergenicity in a host are not well understood. In the current report, comparative analysis of proteins on two dimensional gel electrophoresis (2D-3) and specific IgE immunoblots ofA. fumigatus secretory proteins (1st, 2nd and 3rd week culture filtrate proteins) was carried out. We observed a total of 159 proteins in 1st, 2nd and 3rd week culture filtrates ofA. fumigatus. Specific IgE immunoreactivity was observed in 75 proteins with different intensity. Third week culture filtrate showed maximum number of proteins, 142, and specific IgE immunoreactive proteins, 65. MALDI-TOF analysis resulted in putative identification of two allergens as hypothetical protein YBL057c fromSaccharomyces cereviseae and unnamed protein product fromDebaryomyces hansenii (similar to IPF14568 ofCandida albicans). Identification of a repertoire of specific IgE immunoreactive proteins will facilitate the studies on structure-function relationship of these proteins relevant for diagnosis and pathogenesis.  相似文献   
967.
In this paper the patenting activity of the international pharmaceutical industry in London between 1900 and 1966 is analysed. Although patent data as a measure of industrial activity is not without defects it can be used both as an adjunct to and as a surrogate for more conventional yardsticks such as concentration ratios, sales statistics and so on. The results indicate that patenting activity can be used as both an absolute and relative indicator of an industry's pace of technological change. They help pinpoint the international distribution of pharmaceutical research and development. If analysed by product or process they can aid in the understanding of why an industry's competitive behaviour is or is not primarily one of price rivalry. Finally, they illustrate the continuing role of the individual inventor.  相似文献   
968.
969.
Tångeberg P 《Endeavour》2000,24(4):147-151
The seventeenth-century Swedish Royal warship Vasa was painted and decorated with almost 500 figure sculptures and many carved ornaments. It is probably the most extensive sculptural work in wood to have been preserved from this period in European history. The ship's decorations are of particular importance given the scarcity of knowledge of how sculptures in general, and large ships in particular, were painted in Northern Europe during this period. About 20 different pigments have been characterized and it has been possible to reconstruct the appearance of many of the sculptures and to extend this knowledge to the ship's original appearance.  相似文献   
970.
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