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11.
Yanji Qu Lin Zhuo Na Li Yiqing Hu Weihua Chen Yun Zhou Jinwei Wang Qingmei Tao Jing Hu Xiaolu Nie Siyan Zhan 《PloS one》2015,10(4)
International hospital-based studies have indicated a high risk of cognitive impairment after stroke, evidence from community-based studies in China is scarce. To determine the prevalence of post-stroke cognitive impairment (PSCI) and its subtypes in stroke survivors residing in selected rural and urban Chinese communities, we conducted a community-based, cross-sectional study in 599 patients accounting for 48% of all stroke survivors registered in the 4 communities, who had suffered confirmed strokes and had undergone cognitive assessments via the Montreal Cognitive Assessment (MoCA), Mini-Mental State Examination (MMSE), and Hachinski Ischemia Scale (HIS). Detection of PSCI was based on scores in these neuropsychological scales. Factors potentially impacting on occurrence of PSCI were explored by comparing demographic characteristics, stroke features, and cardiovascular risk factors between patients with and without PSCI. The overall prevalence of PSCI was 80.97% (95%CI: 77.82%-84.11%), while that of non-dementia PSCI (PSCI-ND) and post-stroke vascular dementia (PSD) was 48.91% (95%CI: 44.91%-52.92%) and 32.05% (95%CI: 28.32%-35.79%), respectively. Prior stroke and complications during the acute phase were independent risk factors for PSCI. The risk of recurrent stroke survivors having PSCI was 2.7 times higher than for first-episode survivors, and it was 3 times higher for those with complications during the acute phase than for those without. The higher prevalence of PSCI in this study compared with previous Chinese studies was possibly due to the combined effects of including rural stroke survivors, a longer period from stroke onset, and different assessment methods. There is an urgent need to recognize and prevent PSCI in stroke patients, especially those with recurrent stroke and complications during the acute phase. 相似文献
12.
Ontogeny of head and caudal fin shape of an apex marine predator: The tiger shark (Galeocerdo cuvier)
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Amy L. Fu Neil Hammerschlag George V. Lauder Cheryl D. Wilga Chi‐Yun Kuo Duncan J. Irschick 《Journal of morphology》2016,277(5):556-564
How morphology changes with size can have profound effects on the life history and ecology of an animal. For apex predators that can impact higher level ecosystem processes, such changes may have consequences for other species. Tiger sharks (Galeocerdo cuvier) are an apex predator in tropical seas, and, as adults, are highly migratory. However, little is known about ontogenetic changes in their body form, especially in relation to two aspects of shape that influence locomotion (caudal fin) and feeding (head shape). We captured digital images of the heads and caudal fins of live tiger sharks from Southern Florida and the Bahamas ranging in body size (hence age), and quantified shape of each using elliptical Fourier analysis. This revealed changes in the shape of the head and caudal fin of tiger sharks across ontogeny. Smaller juvenile tiger sharks show an asymmetrical tail with the dorsal (upper) lobe being substantially larger than the ventral (lower) lobe, and transition to more symmetrical tail in larger adults, although the upper lobe remains relatively larger in adults. The heads of juvenile tiger sharks are more conical, which transition to relatively broader heads over ontogeny. We interpret these changes as a result of two ecological transitions. First, adult tiger sharks can undertake extensive migrations and a more symmetrical tail could be more efficient for swimming longer distances, although we did not test this possibility. Second, adult tiger sharks expand their diet to consume larger and more diverse prey with age (turtles, mammals, and elasmobranchs), which requires substantially greater bite area and force to process. In contrast, juvenile tiger sharks consume smaller prey, such as fishes, crustaceans, and invertebrates. Our data reveal significant morphological shifts in an apex predator, which could have effects for other species that tiger sharks consume and interact with. J. Morphol. 277:556–564, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
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Lin Xiang Lin Shuang Liu Yuanlan Zhao Haiyan Wang Li Hasi Wuliji 《Plasmonics (Norwell, Mass.)》2018,13(5):1749-1758
Plasmonics - Large-scale ordered two-dimensional (2D) superlattices at oil/water interface were fabricated using single-crystal Au nanospheres (NSs) with different diameters as building blocks. A... 相似文献
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Kuo Huang Ling Bai Jiun Chen Yun Wen Peng Shih Chong Tsai Fu Chuo Peng Chung Kuang Yang 《Mycotoxin Research》1987,3(2):58-64
The chemical reaction of cleavaging territrem B to give 3,4,5-trimethoxy benzoic acid by alkaline hydrogen peroxide was investigated. The method was applied for confirmation of the chemical structure of the aromatic moiety of territrem A, A’, B, and B’. The physicochemical properties of the aromatic cleavage product of territrem Aindicated the structure as 3,4-methylendioxy, 5-methoxy benzoic acid (or 4-methoxy, 6-carboxy, 1, 3-benzodioxole). The experiment also gave the evidences that territrem A and A’, on the other hand territrem B and B’ have the identical aromatic moieties on their structures. 相似文献
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白洋淀和太湖地区鸟类绦虫区系的比较研究 总被引:1,自引:0,他引:1
本文对白洋淀和太湖地区鸟类绦虫区系进行了比较研究,并对太湖鸟类绦虫区系作了初步分析。结果表明,鸟类绦虫区系分布与宿主区系分布密切相关,亲缘关系相近的宿主有许多相同的或亲缘相近的绦虫,这种现象为研究宿主与寄生虫的演化提供了可靠途径;发现鸟的越冬地绦虫种类比迁徙地种类丰富,分析其原因,除温、湿度、中间宿主等生态条件之外,与鸟的迁徙有一定关系。太湖地区的绦虫具有北方型和随遇型,亦有世界性种类和东半球广布种,提出了两地区家禽和野生鸟类所寄生的共同种类的绦虫。 相似文献
19.
本文以普通小麦(Triticum aestivum L.)根端分生组织为材料,在透射电镜下对间期细胞核内的集缩染色质的高层次结构进行了研究。在其中观察到直径约为20—25nm、50nm及110—120nm 的不同等级染色线,并且发现直径110—120nm 的染色线是由50nm 的染色线组成的,而直径约50nm 的染色线是由20—25nm 的染色线组成的。对这三个层次染色质结构之间的集缩方式进行了讨论。 相似文献
20.
Wei de Zhang Fan Qing Li Xiao Yun Zhang Ying Chen 《Biological trace element research》1988,17(1):81-90
The growth of the protozoanBlepherisma is stimulated by Lanthanum (La) at concentrations as low as 0.32 ppm. In mice Yttrium (Y) and Ytterbium (Yb) are absorbed,
accumulated, and metabolized. Both rare earth elements (RE) exhibit a high affinity for teeth and bones, accumulation occurs
and metabolism is slow. In the livers of RE-exposed mice, concentrations are variable. The liver is apparently capable of
absorbing and discharging RE in a manner depending on metabolic activity. The main route of discharge for ingested REs is
the alimentary canal. Exposure of pregnant mice to RE leads to rapid placental transfer of RE; 14.1% of the total amount of
RE administered was detected in newborn mice. Young, developing organisms appear to be especially susceptible to RE accumulation. 相似文献