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1.
本研究工作中,建立了一个有效的甜菜坏死黄脉病毒的分离提纯程序,解决了该病毒粒体易于聚集难以提纯的问题,其操作要点是,(1)通过Sepharose 2B柱层析代替超离心,有效地除去一些小分子量核酸杂质;(2)经PEG再次沉淀浓缩后,调整pH至酸牲(pH3.0),使病毒充分悬浮以减少凝聚;(3)在病毒等电点(pH4.8~4.9)条件下,进一步沉淀以纯化病毒。根据病毒提取物的OD260/OD280比值,算出核酸含量约4.5%。核酸电泳出现4条带,分子量分别为:2.25×10~(?),1.8×10~(?),1.05×10~(?),0.75×10~(?)道尔顿。病毒提取物经超速离心出现4个界面,沉淀系数分别为,200.8S,165S,125.8S,100S。说明甜菜坏死黄脉病毒可能是4组分病毒粒体。病毒粒体含一蛋白亚基,分子量约为2.05±0.05×10~4道尔顿,由16种共199个氨基酸组成。 相似文献
2.
L. Minutini A. Innocenti C. Bertolucci A. Foà 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1995,176(2):281-288
The effects of electrolytic lesions to the suprachiasmatic nuclei of the hypothalamus (SCN) on circadian rhythms of locomotor activity were examined in ruin lizards Podarcis sicula maintained in constant darkness and constant temperature (29°C). All lizards (N=15) in which the lesion damaged 80% or more of the SCN became behaviorally arrhythmic. On the contrary, locomotor rhythms persisted in all cases (N=11) when the SCN remained intact and lesions were confined to neighbouring regions of the preoptic area. Taken together with previous work which demonstrates that the pineal and the retinae are not essential for the persistence of circadian locomotor rhythmicity in Podarcis sicula and with recent evidence showing the homology between the SCN of lizards and those of mammals the present results strongly support the view that the SCN of Podarcis sicula contain the primary pacemaker(s) for locomotor rhythms.Abbreviations
DD
constant darkness
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LL
constant light
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SCN
suprachiasmatic nuclei of the hypothalamus
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PH
nucleus periventricularis hypothalami
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OC
optic chiasm
- te
length of circadian activity
-
freerunning circadian period 相似文献
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In a previous paper (Hiraba and Sato ) we reported that an accurate mastication might be executed by the cortical processing in bilateral masticatory area (MA)and motor cortices. The aim of this study was to determine if cats with lesion of either unilateral or bilateral MA showed changes in mastication. After exploring mechanoreceptive fields and motor effects of mastication-related neurons (MRNs) in MA using the single unit recording and intracortical microstimulation methods, we made various lesions in MAs with injections of kainic acid (0.1%, 2.0?µl). Since the MA was divided into facial (F) and intraoral (I) projection areas as reported in the previous paper, cats with the unilateral lesion in F or I, and with the bilateral lesion in F & F, I & I or F & I (F on one side and I on other side) were prepared. Cats with unilateral lesion in F or I and with bilateral lesion in F & I showed no changes in mastication except for prolongation of the food intake and masticatory periods. Cats with bilateral lesion into F & F, or I & I showed wider jaw-opening during mastication. Particularly, the latter group showed enormous jaw-opening, delay in the start of mastication and difficulty in manipulating food on the tongue. In all cats with lesions of each type, masticatory and swallowing rhythms remained normal. These findings suggest that accurate mastication is executed by the close integration between F & F and I & I of the bilateral MA. 相似文献
5.
6.
Diagnosis and phylogenetic analysis of orf virus in Aleppo and Saanen goats from an outbreak in Turkey 总被引:1,自引:0,他引:1
正Dear Editor,The Poxviridae family is divided into Chordopoxvirinae and Entomopoxvirinae genera.Parapoxvirus is one of 11genera in the Chordopoxvirinae genus,including orf virus(ORFV),bovine papular stomatitis virus(BPSV),pseudocowpox virus(PCPV)and parapoxvirus of red deer in New Zealand(PVNZ)(Skinner et al.,2012).This virus,also known as contagious ecthyma or contagious pustular dermatitis,is a viral skin disease causing edematous proliferative lesions,most often in hairless skin 相似文献
7.
Down-regulation of antioxidative capacity in a transgenic tobacco which fails to develop acquired resistance to necrotization caused by TMV 总被引:5,自引:0,他引:5
Antioxidant status was assayed in leaves of two local lesion hosts of tobacco mosaic virus (TMV), namely in wild-type Xanthi-nc tobacco and in NahG transgenic tobacco, the latter of which is not able to accumulate salicylic acid (SA) and therefore is unable to develop systemic acquired resistance (SAR). Activities of several enzymes related to antioxidative defense, and the levels of glutathione, chlorogenic acid and rutin were studied. The majority of antioxidant enzymes were less active in uninfected NahG tobacco than in Xanthi-nc. Furthermore, important enzymatic and non-enzymatic antioxidants were down-regulated in TMV-infected NahG plants, as compared to Xanthi-nc. Correspondingly, SA pretreatment primed the leaves for stronger induction of antioxidants in infected Xanthi-nc, but not in NahG tobaccos. The antioxidant status of NahG tobacco even decreased after an attempted induction of SAR, while the antioxidative level increased in Xanthi-nc leaves in which the SAR was successfully induced. After infection, a greater accumulation of superoxide and H 2 O 2 , and a more intensive necrotization was positively correlated with the reduced capability of NahG leaf tissue to detoxify reactive oxygen species. 相似文献
8.
Numerically equal groups of between five and ten young Merino and Dorper sheep were artificially infested with sheep scab
mites, Psoroptes ovis. Separate groups of sheep were infested during the early winter of two successive years as well as during the early summer
of the second year. Lesion growth was measured at two-weekly intervals for a period of six weeks during the first winter and
for eight weeks during the second winter and in the summer. The rate of lesion growth and mean lesion size on Merino sheep
was significantly greater than that on Dorper sheep at each two-weekly recording during the winter of both years. The rate
of growth of the lesions did not differ significantly between the two sheep breeds during summer, although, with the exception
of eight weeks post-infestation, the mean lesion size on Merino sheep was significantly larger than that on Dorper sheep at
each assessment.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
9.
10.
Transgenic tobacco plants expressing an inhibitor of ubiquitin-dependent protein degradation, ubiquitin variant ubR48, spontaneously
formed necrotic lesions and displayed altered responsiveness to tobacco mosaic virus attack. These plants were analyzed for
the accumulation of defense-related compounds and the expression of pathogenesis-related proteins, which serve as convenient
markers for systemic acquired resistance. Callose was detected in the cells of vascular bundles and in the leaf blade. In
addition, ubR48 transgenic plants constitutively accumulated enhanced levels of salicylic acid (SA) and/or its glucoside.
Accumulation of SA glucoside coincided with high levels of pathogenesis-related protein 1, underscoring the similarity of
certain changes in ubR48-expressing plants to an authentic defense reaction.
Received: 8 December 1997 / Revision received: 25 February 1998 / Accepted: 15 March 1998 相似文献