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1.
金华北山三种啮齿动物身体热值、脂肪和水分含量的研究   总被引:6,自引:2,他引:4  
研究了浙江金华3种啮齿动物的身体热值,脂肪含量和水分含量。成年社鼠、褐家鼠和白腹巨鼠生物量热值季节变动范围分别为6.2097-7.657KJ/g,6.153-7.096KJ/g,6.199-12.033KJ/g;水分含量为66.64%-69.75%,67.48%-70.19%,54.64%-72.37%;灰分含量不存在季节差异,年平均值分别为12.50%,12.23%,10.49%。神鼠脂肪含量春  相似文献   

2.
洋葱种子含水量与贮藏温度对其寿命的影响   总被引:14,自引:0,他引:14  
不同含水量(MC 7.1%-1.2)的洋葱种子贮藏在35℃、室温、15℃和5℃条件下1-3年,适度超于处理能延长种子的贮藏寿命;种子的贮藏寿命与种子含水量和贮藏温度密切相关。种子贮藏的最适含水量随温度的改变而发生相应的变化,35℃时MC为3.4%;室温时为3.4%-3.5%;15℃时为4.5%-5.1%。MC≤2.2%不利于延长种子寿命。在室温自然条件下贮藏1-3年,适度超干种子(MC3.4%)内MDA和H2O2含量、O2^-产生速率和LOX活性明显地低于未超干种子(MC7.1%)和高度超干种子(MC1.2%),而抗氧化酶AsA-POD 、CAT和SOD的活性显著地高于未超干种子(MC7.1%)和高度超干种子(MC1.2%)。据此认为对脂质过氧化的抑制作用是适度超干种子耐贮藏的生理原因之一。  相似文献   

3.
水分胁迫效应对冬小麦生长发育影响的试验研究   总被引:17,自引:0,他引:17  
利用大型水分试验场遮雨棚遮档自然降水,采用人工定量补水进水进行冬小麦土壤占田间持量40%-50%、45%-50%、50%-55%、50%-60%、55%-60%、60%-70%持续时间分别为5、10、15d水分胁迫处理的控制试验。试验结果表明:控制结束复水后,50%-60%、55%-70%水分胁迫处理诱发冬小麦根、茎、叶、总生物量显著增长或明显减缓其衰老速率。土壤含水量占田间持水量50%-60%处理,具有明显的增产、节水效率,确定土壤含水量占田间持水量55%为冬小麦拔期水分胁迫应增产节水的水分临界指标。  相似文献   

4.
CaCl2处理对标李室温贮藏期生理生化的影响   总被引:1,自引:0,他引:1  
研究了不同浓度的CaCl2溶液处理后,聚乙烯薄膜代包装、室温(30-35℃)下贮藏的奈李的一些生理生化变化。结果表明:采用1.0%的CaCl2溶液处理可减弱奈李的呼吸作用和在一定程度上降低贮藏后期含水量、电导率,并能维持较高的维生素C、可溶性因形物含量和过氧化物酶(POD)活性。  相似文献   

5.
本文利用培养的大鼠大脑皮层神经元,在不同浓度马桑内酯(5μmol/L~250μmol/L)作用后12、24、48小时,应用双抗夹心法检测各时间点培养上清中γ-氨基丁酸和生长抑素含量。结果表明,各浓度中以25μmol/L马桑内酯作用最明显,在此浓度作用后12小时,γ-氨基丁酸分泌受抑(抑制率为8.3%),生长抑素分泌则增加(增加率为20.4%)。作用后24、48小时,γ-氨基丁酸分泌进一步受抑(抑制率为10.6%、14.5%),而生长抑素分泌则呈现增加幅度降低趋势(增加率为11.7%、8.2%)。与未加药组相比,γ-氨基丁酸在三个时间点均有统计学意义(P<0.05),而生长抑素只在加药后12小时有统计学意义(P<0.05)、本文对马桑内酯作用后两种神经递质变化的意义进行了讨论。  相似文献   

6.
棉褐带卷叶蛾安徽种群不同日龄雌蛾性信息素的个体变异   总被引:1,自引:0,他引:1  
采用单个性信息素腺体分析技术对棉褐带卷叶蛾安徽种群6个不同日龄,雌蛾性信息素二元组分进行了定量分析。结果表明各日龄组雌蛾的性信息素含量差异显(P<0.01),随着雌蛾日龄的增加,性信息素含量呈现由低到高,再由高到低的变化曲线。二元组分中Z-11-14:Ac的比例具有较狭窄的个体变异范围(CV%=6.43);而Z-9-14:Ac的CV%=15.91。羽化当天和1天的雌蛾性信息素中Z-9-14:Ac  相似文献   

7.
990-1994年3-10月,在山西庞泉沟国家级自然保护区,对白繁殖生态进行了研究。研究表明,该鸟在本区为夏候鸟,3月底迁来,10月上旬迁离,多在山涧溪流、池塘、水沟边活动。种群密度遇见数在繁殖前为170只/km,繁殖后177只/km,繁殖后比繁殖前增长412%。食物以昆虫为主,最早产卵于5月11日,每窝卵数3-6枚,孵卵期12-14d,孵化率80%-100%。  相似文献   

8.
油蒿挥发油的化感作用研究   总被引:29,自引:0,他引:29       下载免费PDF全文
对毛乌素沙地油蒿挥发油的化感作用(Alelopathy)及其化学成分进行了研究。结果表明:油蒿挥发油对苋、诸葛菜、萝卜种子萌发和幼苗生长具有不同程度的抑制作用;对小麦种子萌发几乎无影响,但对其幼芽和幼根的生长具一定影响。抑制作用最强的是对苋种子,挥发油组最终萌发率18%,比对照组减少71%,对其幼芽和幼根的生长影响也很明显。用GC、GC-MS-DS联用方法,共鉴定43个化合物,其中相对百分含量在1.5%以上的化合物有如下14种:1)α-蒎烯(α-pinene),2)桧烯(Sabinene),3)β-蒎烯(β-pinene),4)月桂烯(Myrcene),5)对伞花烃(ρ-cymene),6)柠檬烯(Limonene),7)β-水芹烯(β-phelan-drene),8)β-顺式罗勒烯(β-cis-ocimene),9)β-反式罗勒烯(β-trans-ocimene),10)松油烯-4-醇(Terpinen-4-ol),11)α-姜黄烯(α-curcumene),12)茵陈炔(Capilene),13)橙花叔醇(Nerolidol),14)匙叶桉油烯醇(Spathulenol)。  相似文献   

9.
在风洞中观察了亚洲玉米螟雄蛾对不同剂量不同比例的二组份及三组份的人工合成性信息素(14:oAc, E-12-14: oAc和 Z-12-14:oAc)的行为反应。 Z-12-14: oAc+E-12-14: oAc 二组份诱芯中以比例为37.5%E到62.5%E之间的诱芯效果最好,有71%-78%的雄蛾到达诱芯。三组份诱芯中以工4:Ac: Z-12-14: oAc: E-12-14: oAc=1: 5: 4的效果最好,雄蛾到达诱芯的百分率(71%)与二组份诱芯相比无显著差异。但是剂量反应实验显示三组份诱芯的有效剂量范围比二组份诱芯宽,二组分诱芯及三组份诱芯在风洞试验中的最佳剂量范围分别为 100ng到 1000ng和 100 ng到 10 000ng。低剂量的情况下三组份的诱芯效果要好于二组份诱芯。三组份诱芯对于低到 1ng的剂量仍能引起 10%的雄蛾到达诱芯,而在此剂量下二组份诱芯不能引起定向及其以后的各步行为反应。  相似文献   

10.
超干贮藏榆树种子萌发过程中ATP和可溶性糖含量的变化   总被引:12,自引:0,他引:12  
汪晓峰  杨世杰等 《植物生理学报》2001,27(5):413-418,T001
经过超干(种子含水量3.73%)贮藏(普通室温下2个月)的榆树种子萌发过程中ATP与可溶性糖含量和ATP酶,淀粉酶,抗氧化酶的活性都高于对照(种子含水量9.34%,普通室温下贮藏),说明适度的超干贮藏有利于保持种子活力。  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

16.
Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

17.
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

18.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细  相似文献   

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For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

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