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1.
由植物革兰氏阴性病原菌编码产生的harpin蛋白是激发植物过敏反应的主要因子,具有显著的诱导植物抗性和促进生长发育等多种生物学效应,同时也是研究植物抗病信号传导的理想模型。基于对harpin蛋白的深入研究,国外已开发出新型、高效、安全的生物农药。本文综述了近年来harpin蛋白的研究进展。  相似文献   

2.
植物叶蛋白提取效率研究   总被引:1,自引:0,他引:1  
植物叶蛋白工业化生产要取得良好的经济效益,不仅要采用先进的生产工艺,还与植物原料的蛋白含量、提取效率密切相关。我们在对180种植物进行蛋白质含量分析后,筛选出高含量叶蛋白的40多种植物的基础上,进行了不同植物叶蛋白提取效率的研究。1材料与方法1.1材料:采集构树等9种植物鲜叶为材料。1.2方法:称取鲜叶100克,加100ml水匀浆,4000转/分离心去残渣,上清液50℃沉淀得绿蛋白浓缩物,再用90℃处理清液得白蛋白浓缩物。分别用凯氏定氮法测定绿蛋白、白蛋白浓缩物和残渣的氮含量,乘以6.25换算成蛋白质含量。2结果9种植物叶蛋白提取…  相似文献   

3.
转基因植物生产基因工程疫苗技术   总被引:5,自引:0,他引:5  
用转基因植物生产有用的外源蛋白是一个有吸引力的廉价生产系统,它可能替代传统的外源蛋白生产体系。通过外源基因的瞬时表达或稳定表达方式,多种基因工程疫苗已在植物中表达成功,并保持良好的免疫原性。本文概要介绍了国内外利用转基因植物生产疫苗的研究现状,并对转基因植物生产疫苗的潜在优势、存在的问题及其相关技术作一综述。  相似文献   

4.
植物耐盐遗传性及分子标记研究进展   总被引:4,自引:0,他引:4  
回顾了植物耐盐遗传基础的研究成果,概述了植物在渗透调节、钙调蛋白、通道蛋白等方面对盐胁迫的生理反应;介绍了RAPD分子标记在植物耐盐育种上的应用,特别对与大豆、水稻、苜蓿等植物的耐盐性紧密连锁的分子标记的研究进展作了综述。  相似文献   

5.
盐胁迫下植物离子转运的分子生物学研究   总被引:9,自引:5,他引:4  
植物细胞质是生理生化反应的集中部位,植物的正常生长发育需要维持细胞内离子的相对平衡状态,而细胞质保持相对恒定的K /Na 的能力是植物盐适应性的重要决定因素之一。各种离子的相对平衡是许多生理过程的综合结果,包括离子的内流、外流、外排和区域化等。离子的转运是由位于膜上的转运蛋白完成的,并受到多基因的调控。离子转运蛋白的分子生物学研究近年来发展很快,本研究将介绍有关方面的研究进展。  相似文献   

6.
HD-Zip(Homologous structural Domain-leucine Zip,同源结构域-亮氨酸拉链)蛋白是植物特有的转录因子,其中HB1属于HD-ZIP I亚族。通过调节植物体内的内源激素含量变化,HB1转录因子可以提高植物对干旱、高盐等不利环境的抵抗能力。本文为探究紫花苜蓿HB1基因的生物学功能,采用RT-PCR技术成功克隆了MsHB1基因。其编码区长867 bp,编码288个氨基酸。氨基酸序列分析结果表明,HB1蛋白为不稳定蛋白。系统发育树分析表明HB1蛋白与蒺藜苜蓿(Medicago truncatula)同源蛋白的亲缘关系接近。构建MsHB1的原核表达载体,在大肠杆菌BL21中成功诱导紫花苜蓿MsHB1蛋白表达,Western Blot也证实MsHB1蛋白表达成功。表达分析显示:MsHB1基因在紫花苜蓿根、茎、叶中均有表达,在不同发育阶段中,幼嫩的叶片中表达最高。MsHB1在NaCl和ABA处理时的基因表达水平升高,推测MsHB1可能在紫花苜蓿高盐等胁迫应答方面发挥着重要的作用。  相似文献   

7.
叶蛋白的提取技术   总被引:1,自引:0,他引:1  
叶蛋白的提取技术四川省温江农业学校周世朗叶蛋白是优质的蛋白质补充饲料,资源也很丰富,开发应用叶蛋白发展养殖业,很有前途。一、叶蛋白的概念与营养(一)什么叫叶蛋白叶蛋白又称青草胶,它是从绿色植物中提取出来的一种蛋白质。这种蛋白质来源于植物的茎叶,故称其...  相似文献   

8.
GASA蛋白(Gibberellic acid-stimulated in arabidopsis)是植物特有的小分子蛋白,通过参与调控相关植物激素信号转导与生长发育过程在植物体内发挥着重要作用。深入研究GASA蛋白的功能对阐明植物小分子蛋白作用机理具有重要理论研究意义。狗尾草(Setaria viridis)是新型的C4模式植物,对其GASA基因家族的研究尚未见报道。本研究采用生物信息学技术,基于狗尾草全基因组序列,分析获得12个GASA基因。进一步生物信息学分析结果表明,狗尾草GASA家族基因结构简单,GASA蛋白可划分为三个进化枝,均含有3~4个模体结构,12个基因启动子区共同含有响应脱水、低温、高盐及植物激素的顺式作用元件。采用实时荧光定量PCR技术对短期干旱(15%聚乙二醇6000)、冷害(4℃)、盐害(150 mM NaCl)逆境胁迫下狗尾草叶片中GASA基因表达模式进行了初步研究。结果表明,狗尾草不同GASA基因对各类逆境胁迫有响应。研究结果将为进一步开展GASA基因参与逆境胁迫的功能解析提供初步的实验证据。  相似文献   

9.
HKT蛋白与植物耐盐性研究进展   总被引:1,自引:0,他引:1  
赵常玉  李剑  张金林  王锁民 《草业科学》2012,29(10):1604-1612
盐胁迫是一种严重影响植物生长的非生物胁迫,植物在长期进化过程中形成了各种机制来抵御和适应盐胁迫。高亲和性钾离子转运蛋白(HKT)是植物中普遍存在的一类蛋白,对高等植物体内Na+再循环,维持植株地上部特别是叶片中的低Na+浓度和高K+/Na+具有重要作用。本研究对HKT蛋白的分子特性、结构与功能及其与植物耐盐性的关系进行了综述。  相似文献   

10.
植物铁蛋白的研究进展   总被引:1,自引:0,他引:1  
陈丽萍  张丽静  傅华 《草业学报》2010,19(6):263-271
铁蛋白(ferritin)是一种铁结合和存储蛋白,广泛存在于动物、植物和微生物体内,是生物体内的一种保守性较高的多功能多亚基蛋白。植物铁蛋白作为专门的贮铁蛋白,是植物光合作用和固氮等生化反应的铁源,不仅调节体内铁的含量,而且是一种重要的胁迫反应蛋白,调控铁生物功能,在植物的发育、抵抗氧化损害等方面发挥重要的作用。本研究从铁蛋白的结构、功能及基因克隆、表达和遗传转化等方面,概述了其在植物分子生物学中的研究进展及其应用情况。  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
14.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

15.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  相似文献   

16.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

17.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

18.
The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.  相似文献   

19.
<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.  相似文献   

20.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

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