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141.
142.
豆科黄结属模式及其相关种名的考证   总被引:4,自引:0,他引:4  
长期以来,Termopsis lanceolata R.Br.被误认为是黄华属的模式。根据有关文献考证和国际植物命名法规,作者为认T.;lanceoltata是一个不合法名,黄华属的合法模式应为Thermopsis Lupinoides(L.)Link.分布于东北亚,花具互生花的黄华长期被误定为T。lupinoides(L.)Link,应更正为Thermopsis fabacea(Pall)DC.。  相似文献   
143.
商州产大马士革玫瑰精油研究   总被引:1,自引:0,他引:1  
采用ISO9842:2003玫瑰油标准,对陕西商州引种的保加利亚主栽玫瑰品种“Kazanluk”(RosadamascenaMiller)精油进行分析。结果表明,该玫瑰精油香气具有天然玫瑰花香,香气细腻、柔和、飘逸。油为液体,淡黄色,相对密度(20/20℃)0.8599,折光指数(20℃)1.4592,旋光度(20℃)-4.3°,冻点20.6℃,酯值11.9,这些物理指标达到了标准要求。大量主香成分相对含量:乙醇0.5%,香茅醇45.5%,橙花醇4.5%,香叶醇7.6%,苯乙醇2.9%,十七烷烃1.13%,十九烷烃15.5%,二十一烷烃5.0%。这些成分含量与原产地保加利亚玫瑰油成分范围有一定差异,但与摩洛哥同类玫瑰油标准相符,可以作为商品油在国际市场销售。  相似文献   
144.
Little is known about the association of endothelial nitric oxide synthase (NOS3) gene polymorphisms and the presence of insulin resistance and the early evolution of atherosclerosis in nondiabetic subjects with cardiovascular disease (CAD) and stent implantation. The present study was performed in an attempt to better understand whether metabolic, endothelial, and angiographic findings characteristic of subjects with cardiovascular disease and in-stent restenosis are related to NOS3 variants. This is a case-control study performed from 2002 to 2006. All subjects admitted to the study were recruited in the Nord-Centre of Italy, most from Milan and its surrounding towns. Measures of glucose tolerance, insulin sensitivity, markers of endothelial dysfunction, forearm vasodilation, and adipokine levels were determined and associated to the frequency of two single-nucleotide polymorphisms of NOS3, i.e., Glu298Asp (rs1799983, G/T) and rs753482 (intron 18 A/C). A total of 747 subjects, not known to have diabetes, were evaluated: 333 subjects had asymptomatic CAD, 106 subjects had unstable angina and were evaluated for in-stent restenosis 6 mo after stent placement, and 308 were control subjects. The presence of TT and CC minor alleles was significantly greater in case groups compared with control subjects. At phenotypic level, subjects with the polymorphisms were characterized by hyperinsulinemia and reduced reactive hyperemia, whereas increased leptin and decreased adiponectin levels were present in subjects with restenosis in the presence of reduced minimal lumen diameter and length of stenosis almost doubled. Hyperinsulinemia, endothelial dysfunction, and a more atherogenic profile seem to be peculiar features of subjects with asymptomatic CAD and restenosis carrying NOS3 gene variants.  相似文献   
145.
Passive muscle stretching can be used in vivo to assess the viscoelastic properties of the entire musculo-articular complex, but does not allow the specific determination of the muscle or tendon viscoelasticity. In this respect, the local muscle hardness (LMH) of the gastrocnemius medialis (GM) belly was measured during a passive ankle stretching of 10 subjects using transient elastography. A Biodex isokinetic dynamometer was used to stretch ankle plantar flexors, to measure ankle angle, and the passive torque developed by the ankle joint in resistance to the stretch. Results show that the LMH increased during the stretching protocol, with an averaged ratio between maximal LMH and minimal LMH of 2.62+/-0.46. Furthermore, LMH-passive torque relationships were nicely fitted using a linear model with mean correlation coefficients (R(2)) of 0.828+/-0.099. A good reproducibility was found for the maximal passive torque (ICC=0.976, SEM=2.9Nm, CV=5.5%) and the y-intercept of the LMH-passive torque relationship (ICC=0.893, SEM=105Pa, CV=7.8%). However, the reproducibility was low for the slope of this relationship (ICC=0.631, SEM=10.35m(-2), CV=60.4%). The y-intercept of the LMH-passive torque relationship was not significantly changed after 10min of static stretching. This result confirms the finding of a previous study indicating that changes in passive torque following static stretching could be explained by an acute increase in muscle length without any changes in musculo-articular intrinsic mechanical properties.  相似文献   
146.
The role of sexual selection in determining the nature and direction of sexual size dimorphism may depend upon the timing of sexual selection, and this may also influence the variation in male size. For example, selection through sperm competition favours smaller males in the highly sexually size dimorphic orb-weaving spider Nephila edulis , whereas larger males are better able to exclude their smaller rivals from the central hub of the web where mating takes place. We investigate experimentally the role of body size and hub tenure in determining male fertilization success when males of different sizes compete for a single female over a 24-h period that includes a period of darkness. Our results confirm that small and large males obtain similar paternity share but that, in contrast with previous studies, hub tenure does not translate into greater paternity share. Unexpectedly, smaller males are at greater risk of postmating sexual cannibalism than larger males, suggesting that natural selection through sexual cannibalism may place a lower limit on male size.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 94 , 355–363.  相似文献   
147.
Mmutations in paraplegin, a putative mitochondrial metallopeptidase of the AAA family, cause an autosomal recessive form of hereditary spastic paraplegia (HSP). Here, we analyze the function of paraplegin at the cellular level and characterize the phenotypic defects of HSP patients' cells lacking this protein. We demonstrate that paraplegin coassembles with a homologous protein, AFG3L2, in the mitochondrial inner membrane. These two proteins form a high molecular mass complex, which we show to be aberrant in HSP fibroblasts. The loss of this complex causes a reduced complex I activity in mitochondria and an increased sensitivity to oxidant stress, which can both be rescued by exogenous expression of wild-type paraplegin. Furthermore, complementation studies in yeast demonstrate functional conservation of the human paraplegin-AFG3L2 complex with the yeast m-AAA protease and assign proteolytic activity to this structure. These results shed new light on the molecular pathogenesis of HSP and functionally link AFG3L2 to this neurodegenerative disease.  相似文献   
148.
日光温室栽培对杏花及果实生长发育的影响   总被引:18,自引:0,他引:18  
对日光温室内与露地栽培的金太阳杏的花期物候、花型及果实生长发育进行了系统观察与分析,结果表明,日光温室栽培比露地栽培的始花期提前33d,花期延长4d,不完全花比例上升33.25%;果枝上花的有效性顺序由露地时的中果枝>长果枝>短果枝>花束状果枝变为温室栽培的短果枝>花束状果枝>中果枝>长果枝;日光温室栽培使杏果实发育的第 、 阶段延长,第 阶段缩短,整个生育期延长15d。统计分析认为:日光温室栽培的第 阶段生长速率显著低于露地,第 阶段的累积生长量显著高于露地。较低的夜间温度是造成温室内杏果实第 阶段较长、生长较慢以及果个变大的原因。  相似文献   
149.
Section Arachis is the largest of nine sections in the genus Arachis and includes domesticated peanut, A. hypogaea L. Most species are diploids (x=10) with two tetraploids and a few aneuploids. Three genome types have been recognized in this section (A, B and D), but the genomes are not well characterized and relationships of several newly described species are uncertain. To clarify genomic relationships in section Arachis, cytogenetic information and molecular data from amplified fragment length polymorphism (AFLP) and the trnT-F plastid region were used to provide an additional insight into genome composition and species relationships. Cytogenetic information supports earlier observations on genome types of A. cruziana, A. herzogii, A. kempff-mercadoi and A. kuhlmannii but was inconclusive about the genome composition of A. benensis, A. hoehnei, A. ipaensis, A. palustris, A. praecox and A. williamsii. An AFLP dendrogram resolved species into four major clusters and showed A. hypogaea grouping closely with A. ipaensis and A. williamsii. Sequence data of the trnT-F region provided genome-specific information and showed for the first time that the B and D genomes are more closely related to each other than to the A genome. Integration of information from cytogenetics and biparentally and maternally inherited genomic regions show promise in understanding genome types and relationships in Arachis.  相似文献   
150.
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