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41.
高粱对丝黑穗病的抗性及遗传研究   总被引:5,自引:0,他引:5  
1981—1985年在人工接种的条件下,对1239份高粱品种资源,进行了抗丝黑穗病性鉴定。与此同时,用17个抗性不同的品种系,按照不完全双列杂交设计,进行了高粱对丝黑穗病的抗性遗传研究。结果表明,高粱对丝黑穗病的抗性遗传方式因品种而异。有的品种系具数量性状遗传特点,有的则具有质量性状遗传特点。抗病性属数量性状遗传的品种系,其抗性主要是受加性基因控制。  相似文献   
42.
泡状饶氏藻营养细胞的超微结构研究   总被引:1,自引:0,他引:1  
本文报道我国特有的一种绿藻门植物-泡状饶氏藻营养细胞的超微结构特征,植物体由3层细胞组成,外层细胞最小,细胞质比较丰富,含有较多的各种细胞器,液泡体积较小,中层细胞具有很大的中央液泡,细胞质成为贴壁的薄层,各种细胞器结构仍清晰可见,内层细胞极度液泡化,细胞质呈现退化状态,周生的片状叶绿体上有许多大小不等的穿孔,使叶绿体呈网孔状外貌,叶绿体主要由许多成对的类囊体组成,叶绿体上往往有几个蛋白核,蛋白核经常被1或2条类囊体穿过,呈现分隔状,本文也报道了泡状饶氏藻的线粒体,质体,内质网,高尔基体和核内微管的结构特征,根据泡状饶氏藻的类囊体形态与Ulva mutabilis非常相似以及蛋白核的超微结构特征,它与石莼科植物可能有较密切的亲缘关系,属于绿藻门中进化的类群。  相似文献   
43.
利用单克隆抗体(McAb)进行病毒病的治疗是人们所关心的一个重大课题。 流行性乙型脑炎(乙脑)是一种严重威胁人民健康的急性传染病,病死率高,后遗症严重。国内外目前尚无特效疗法。陈伯权等用乙脑病毒皮下或腹腔感染3周龄小白鼠24、48小时及5天后,分别用乙脑病毒51-8McAb进行治疗,平均治愈率分别为78%、73%及22%。  相似文献   
44.
MacELISA、RPHI和IFAT用于流行性出血热早期诊断的比较   总被引:2,自引:0,他引:2  
比较了IgM捕获ELISA(MacELISA)、反向间接血凝抑制试验(RPHI)和间接免疫荧光抗体试验(IFAT)检测流行性出血热(EHF)病人血清特异性抗体的结果。MacELISA对急性期血清IgM抗体的阳性检出率与RPHI对总抗体的阳性检出率相近,两法都具有较高的敏感性。而IFAT检测IgG抗体的阳性率则较低。总抗体滴度(RPHI)与IgG抗体滴度(IFAT)相关(r=0.542,P<0.01),而与IgM抗体滴度(MacELISA)无明显相关(r<0.1)。但进一步研究发现,3日内血清IgM抗体滴度与总抗体滴度(RPHI)存在相关关系(r=0.701,P<0.01),表明IgM抗体可能也与发病初期RPHI的较高的阳性检出率有关。本工作表明,MacELISA作为一种早期诊断方法具有高度的特异性和敏感性,而RPHI操作简便、快速、敏感性高,但存在一定的非特异性。研究还发现,流行区临床诊断为EHF的病人,IFAT(IgG)和RPHI检测均阳性,而MacELISA(IgM)阴性,提示用RPHI进行血清学诊断时,检查双份血清是必要的。  相似文献   
45.
The human neurofilament (H) promoter contains multiple binding sites for nuclear proteins including a Proximal (Prox) site centered around the sequence GGTTGGACC and an adjacent pyrimidine (Pyr) tract site centered around the sequence CCCTCCTCCCC. Surprisingly binding to a probe containing the Prox/Pyr region of the NF(H) promoter was competed in gel shifts by an oligonucleotide containing only an Sp1 binding site (GGGGCGGGG). Supershift assays with a polyclonal anti-Sp1 antisera confirmed that Sp1 was part of the complex formed with the Prox/Pyr probe. However neither bacterially expressed Sp1 516C or vaccinia virus expressed full-length Sp1 778C bound to the Prox or Pyr sequences in DNase I footprints or gel shift assays. Gel shift competitions and supershift assays with probes containing either Prox or Pyr tract sites alone demonstrated targeting of Sp1 to the Prox binding site and identified a non-Sp1 containing complex which contains a Prox binding protein. Adding exogenous Sp1 to a HeLa nuclear extract enhanced the Sp1-containing complex but had no effect on the Prox complex. These studies show that Sp1 can be targeted to a non-Sp1 site in the human NF(H) promoter through protein/protein interactions with a distinct sequence specific DNA-binding protein.  相似文献   
46.
头端延髓腹外侧区注射5—羟色胺对应激性高血粘度...   总被引:3,自引:0,他引:3  
翁可  郭学勤 《生理学报》1992,44(3):244-253
Experiments were carried out on 62 wistar rats. The hyperviscosity and elevation of blood pressure were induced by hanging and restraining the rats with their four limbs tied on a frame. It was found that microinjection of 5-HT (25 micrograms/10 microliters) into the 4th ventricle of the brain or bilateral microinjection of 5-HT (4 micrograms/0.5 microliters/site) into rostral ventrolateral medulla (rVLM) reduced stress-induced hyperviscosity (p < 0.01) and elevation of blood pressure (p < 0.01). The effect of 5-HT injected into the 4th ventricle or rVLM was blocked by bilateral microinjection of cinanserine (4 micrograms/0.5 microliter/site) into rVLM. These results suggest that microinjection of 5-HT into 4th ventricle and rVLM could reduce stress-induced hyperviscosity and elevation of blood pressure and these effects were probably mediated via 5-HT receptors in the rVLM.  相似文献   
47.
NMDA受体在海马CA3区习得性TP保持中的作用   总被引:2,自引:1,他引:1  
梁伟国  许世彤 《生理学报》1992,44(4):333-339
The effect of microinjection of 2-amino-5-phosphonovaleric acid (APV), a selective NMDA receptor antagonist, into the rat hippocampal CA3 area on the synaptic efficacy and related conditioned behavior during the acquisition and consolidation of discrimination learning behavior was examined. The results showed: (1) After population spike (PS) amplitude had just increased to the maximum through training i.e. learning-dependent LTP had just formed, APV 1 microliter (2 mmol/L) was injected into CA3 area, then the rats were trained during the time of efficacy of the drug in every experimental block. The result demonstrated that the PS amplitude could not be maintained at the highest level but decreased to the pre-experiment level after 8 blocks. Correct response percentage of rats could not be consolidated with further training but decreased to less than 10%. (2) After the PS amplitude had kept up at the highest level, APV 1 microliter (2 mmol/L) was injected into CA3 area, then the rats were trained during the time of efficacy of the drug in every experimental block, in which case the PS amplitude also could not be maintained at the highest level but decreased to the pre-experiment level after 14 blocks. Correlatively, when the correct response percentage of rats decreased gradually to less than 10%, the conditioned response of the animals extinguished, but its extinction speed was slower than it was in result (1). These results suggest that the NMDA receptor in CA3 area plays an important role in the maintenance of the learning-dependent long-term potentiation.  相似文献   
48.
X P Liang  L A Babiuk    T J Zamb 《Journal of virology》1991,65(10):5553-5557
The gIII glycoproteins of bovine herpesvirus 1 (BHV-1) and of pseudorabies virus (PRV) are structurally homologous. Both proteins also play preeminent roles in mediating virus attachment to permissive cells. To directly compare the functional relation between these glycoproteins, we constructed a recombinant BHV-1 in which the BHV-1 gIII coding sequence was replaced by the PRV gene homolog. The resultant recombinant virus efficiently expressed PRV gIII and then incorporated it into its envelope. The levels of PRV gIII expression and incorporation were equivalent to those achieved by the wild-type virus for BHV-1 gIII. The recombinant virus was fully susceptible to neutralization by anti-PRV gIII neutralizing antibody. In addition, the virus attachment and penetration functions, as well as the virus replication efficiency, which were lost by deleting the BHV-1 gIII gene, were restored by expressing the PRV gIII homolog in its place. These results demonstrated that PRV gIII and BHV-1 gIII share complementary functions.  相似文献   
49.
Observations were made following 130 spontaneous aggressive incidents in two small breeding groups of captive golden monkeys (Rhinopithecus roxellanae roxellanae). Participants were observed both during the first 10 min following these incidents and during matched control observations. An increased contact rate was observed between opponents following the aggressive incident. Post-conflict contacts were characterized by a number of behavior patterns: open mouth, rapid grooming, embrace, and crouching. Adult males played an important role as mediator in agonistic disputes among females: males intervened in 93.6% of female fights. It is speculated that this intervention behavior is related to the species' organization into one-male units.  相似文献   
50.
Summary Pseudomonas acidovorans DMR-11, capable of oxidizing dimethyl sulfide (DMS), was isolated from peat biofilter. DMS as a sole carbon or energy source was not degraded, but it was co-degraded in the medium containing organic carbon sources. The removal rate of DMS in heat-treated glucose medium was 1.12×10–17 mole/h cell at 30 °C. Dimethyl sulfoxide (DMSO) was the only product of DMS oxidation and was formed stoichiometrically. DMS was reversibly evolved in excess of DMSO. The cell free extract of strain DMR-11 oxidized DMS in presence of NADPH.  相似文献   
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