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1.
Conclusions On the basis of the high prevalence of circulating HCV found with both HCV PCRs, one might speculate that chances for transmission of HCV among IVDU occur more frequently than for transmission of HBV via similar routes. Conversely, instead of transmission through needle sharing or sexual contact, community acquisition of HCV infections might be of particular importance in IVDU.  相似文献   
2.
吐哈盆地台南凹陷鲁克沁构造带中的北西走向断层受挤压强烈 ,封闭性好 ;而北东走向断层封闭性差 ,常成为油气运移的良好通道。由于本区断块圈闭的有效性差 ,故不具备大规模聚集稀油的条件 ,但对稠变到一定程度的稠油能起较好的封堵作用。鲁克沁构造带高粘重质油的形成是原油运移和成藏阶段双重稠变作用的结果 ,并且油气的聚集是一个动态的过程。随着原油的逐渐稠变 ,所需要的封堵条件逐渐降低 ,油气的聚集过程才趋于稳定。鲁克沁构造带构造后期变革主要表现在构造幅度的增大 ,而未发生强烈的断裂作用 ,因此 ,前侏罗系油藏得以完好地保存  相似文献   
3.
GC/MS法追踪摇头丸杂质体系   总被引:1,自引:0,他引:1  
本文运用GS/MS的总离子流法,选择离子法,对南京地区常见的几种摇头丸进行全面分析,找出与合成途径相关的痕量杂质,根据杂质情况初步确定其合成途径.  相似文献   
4.
There has been much progress in genomics in the ten years since a draft sequence of the human genome was published. Opportunities for understanding health and disease are now unprecedented, as advances in genomics are harnessed to obtain robust foundational knowledge about the structure and function of the human genome and about the genetic contributions to human health and disease. Here we articulate a 2011 vision for the future of genomics research and describe the path towards an era of genomic medicine.  相似文献   
5.
求取剩余油饱和度的一种实用方法   总被引:5,自引:4,他引:1  
分析了水驱油田地质、测井及开发动态特征,提出了用生产井含水率资料结合测井资料求取产层平均剩余油饱和度的方法。阐述了该方法的基本模型和计算过程,并以实例计算说明了这种方法的实际应用效果。结果表明,该方法操作简便、实用性强、计算结果可靠,且能准确反映储层的剩余油分布特征。这种方法也避免了水淹层混合液电阻率、岩电系数和水淹层电阻率求取值失真的影响。  相似文献   
6.
ABSTRACT

Recent data from the mitochondrial genome reveal six lineages of Gulf Coast Waterdogs traditionally classified as Necturus beyeri. Here, we use patterns of colour and body size, along with previously published data, to reveal a large, heavily spotted phenotype with an unstriped larva possessing numerous white spots; we re-describe N. beyeri to correspond to this phenotype. We also reveal a small, weakly spotted phenotype possessing an unstriped larva lacking numerous white spots. This phenotype characterises the Apalachicola and Escambia lineages, which current evidence suggests are paraphyletic. We reject taxonomies that place these two lineages in N. lodingi because the type specimen of this species appears to be a melanistic member of N. beyeri. Therefore, we describe the Apalachicola and Escambia lineages as independent new species.

http://ww.zoobank.org/urn:lsid:zoobank.org:act:C8508CCB-F54F-4DC8-B61D-56966A3F1CC8

http://www.zoobank.org/urn:lsid:zoobank.org:act:F044B2CC-55F0-4FFA-A312-9CAD9E73CD69  相似文献   
7.
A mark - recapture study of the short - horned lizard ( Phrynosoma douglassi ) and the sagebrush lizard ( Sceloporus graciosus ) was performed from 1976 to 1977 in southeastern Idaho. Both species had mean cloacal temperatures of approximately 33 C. However, P. douglassi had more variable cloacal temperatures, particularly during morning and evening periods. This was caused by differences in sleeping sites chosen by the two species. Adults of both species were active from mid - April through late August, with peak activity in June. Juvenile P. douglassi displayed a seasonal activity pattern similar to that of adults. Juvenile S. graciosus were most active later in the year (August), when adults were disappearing. In both species, young - of - the - year appeared in early to mid - August. Adult and juvenile P. douglassi were active during all daylight hours and displayed no activity peaks, whereas young - of - the - year displayed a bimodal activity pattern. Adult and juvenile S. graciosus were active over all daylight hours but had peak activity between 1200 and 1500 h. Ants ( Pogonomyrmex ) were the lizard's principle prey. However, only young - of - the - year P. douglassi had activity patterns that paralleled that of ants on their mounds.      相似文献   
8.
松辽盆地南部的低渗透砂岩储层中普遍存在受断层和沉积微相控制的4组高角度构造裂缝,其中以近东西向裂缝渗透性最好,北西向和北东向两组裂缝对储层中流体的渗流也起着相当重要作用,这3组裂缝是油田开发井网布置时应考虑的主要因素。在泥岩夹层中,除了高角度构造裂缝外,还发育有低角度顺层滑脱裂缝,因此,该区泥岩的吸水能力普遍较强,对注水效果有重要影响,因而在注水时应严格控制注入压力。  相似文献   
9.
渤海湾盆地早第三纪构造样式可归结为5种基本类型和3个演化序列。研究结果表明,构造样式及其演化控制着烃源岩的发育,决定着油气藏的类型和展布,制约着含油气系统的范围。综合考虑含油气系统的各个要素,在渤海湾盆地可划分出6个大的含油气系统,分别位于各个坳陷中,并受坳陷的限制。进一步考虑坳陷内凸起构造单元的分割作用,可划分出13个小的含油气系统。  相似文献   
10.
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