小麦品种对赤霉病的抗扩展性的遗传研究

小麦品种对赤霉病的抗扩展性,是由核遗传和多基因控制的数量性状,遗传力高低因组合不同而异。杂种一代的发病小穗数与抗病亲本,感病亲本及中亲值呈显著的正相关,回归值达0.01显著水准。杂种一代的抗性偏向抗病亲本,有明显杂种优势。用抗病亲本与F_1回交,其抗病性有明显提高。 F_2单株发病小穗数变异范围较大,随着世代的增高,发病小穗数变异幅度缩小,而且在选择的作用下有所减少。作者还就该性状的选择方法作了初步的研究,认为在F_3以后各世代采用系统选择比混合法要好。     

家蚕亲本的数量性状与杂种一代及其杂种优势

家蚕茧质性状的杂种优势,依杂交组合而有不同的表现,全茧最以中×日>中×中>日×日的组配方式,茧层量和茧层率以中×日>日×日>中×中。杂交亲本数量值的大小与F_1代产值多数无显著的相关性,但F_1代与雌亲的相关系数大于雄亲的相关,并多呈正相关关系。杂种优势与亲本值为负相关,以中×日组配方式最显著,中×中次之,日×日最少。根据杂种优势与F_1代产值存在显著的正相关,故可利用杂种优势来提高F_1代的产值。由本试验建立的Y=a+b_1x_1+b_2x_2等各种回归方程式,可供育种工作进行预测杂种一代产值和选择杂交亲本,提高育种效果的预见性和计划性。     

花生体内几种酶的活性与抗锈病性的关系

在锈菌侵染前和侵染后的若干阶段测定了具有不同程度抗性的5个花生品种中的苯丙氨酸解氢酶(PAL),过氧化物酶(PO),多酚氧化酶(PPO)活性,并分析其与抗性的关系。结果表明,PAL是一种诱导酶,在测定的大多数时间内,呈现酶活性越大,抗性越强的趋势;在侵染后的12,24和48h,大多数品种病叶的PO活性高于健叶,基本上是品种愈感病酶活性变化愈大;在健康叶片中,PPO的活性变化与抗锈病性显著相关,但在受锈菌侵染的叶片组织中,PPO的活性变化似与抗性无明显相关。     

光照强度和氮肥对水稻品种抗褐稻虱的影响

本文对12个水稻品种的抗虫性质及其受环境条件的影响进行了研究,结果表明,9个抗级品种有较强的抗生性和非嗜好性,表现于飞虱栖息数量少、生存率低、发育缓慢、分泌蜜露量少和刺探频率高。中抗品种辐包矮21和包选2虽然耐害性很强,但前者的抗生性较后者的稍强,且对取食存有非嗜好性。不同品种的非嗜好性受光照强度的影响程度有显著差异。光照强度减弱和偏施氮肥都会加速水稻植株的死亡,引起抗性减弱甚至消失。但光照强度和拖氮水平对不同品种的抗性表现及植株死亡速度的影响程度并不完全一样,存在着互作效应。     

南繁不同株系桔梗抗病性比较研究

将桔梗在海南育种过程中，不同品种桔梗对叶枯病表现出不同的抗性，抗性最强的株系是“GP12-”，抗性最强的单种是“GP2BC4-1”。     

光温条件影响稻种对褐稻虱抗性的研究

在24～30℃温度范围内,品种抗性在不同光照时数阳光强度的影响下存有极显著的差异。弱、短光照会使品种的抗性减弱甚至丧失。 光温对抗虫机制的影响,首先表现在品种的非嗜好性方面,其中光照时数对非嗜好性有极显著影响,温度和光强度也育显著的影响,30℃比24℃表现的非嗜好性较强。光照时数和光强度对非嗜好性有显著的交互作用。     

钙拮抗药治疗高血压病的分析

<正> 钙拮抗药(Calcium antagonist)原为抗心绞痛、抗心律失常药,现在药物学上把其单列为一类,从1978年开始就用于高血压的治疗。钙拮抗药是由一系列结构不同,药理特性不全相同的药物组成,因此其作用机理既不能用简单的构效关系,也不能用同一机理或同一受体加以阐明,现认为是一类能选择性地减少慢通道的Ca~(2+)内流,干扰细胞内Ca~(2+)的浓度而影响细胞功能的药物。已知Ca~(2+)通道有两类:一为受体     

钙离子与钙调素或三氟拉嗪对离体管蛋白和在体微管的作用

作者曾改变轴浆中Ca~(2+)浓度使在体微管解聚。为了解其作用机理自兔脑提取了微管的亚单位管蛋白,浊度测定发现,无论Ca~(2+)本身抑制离体管蛋白聚合或者钙调素(CaM)增强它的抑制作用都取决于Ca~(2+)浓度。将抗CaM药三氟拉嗪注入大鼠坐骨神经使轴突中的微管解聚,Ca~(2+)与三氟拉嗪伍用则抵消各自解聚微管的作用。实验进一步证明Ca~(2+)调节微管聚合的主要作用途径是通过CaM,提示CaM结合一定数目的Ca~(2+)时能维持微管的聚合,若其浓度降低、结合Ca~(2+)增多或不足均使微管解聚。     

用HPLC研究主要阿片生物碱的遗传类型

研究了罂粟(Papaver somniferum LL.)(二倍体)的两种不同遗传品系(NBRI-1,NBRI-2)与刚毛罂粟(P.setigerum DC.)(四倍体)的种间交叉杂种世代中吗啡、可待因、蒂巴因、那可汀及罂粟碱5种主要生物碱的遗传类型。NBRI-1和NBRI-2是分别从印度本地栽培的两种罂粟品种和通过近亲繁殖或交互受粉所获得的高度遗传同型结合性子代中选择出来;刚毛罂粟则来自地中海地区天然野生植物。     

氟喹诺酮类药物治疗性病性尿道(生殖道)炎效果评价

目的　评价对比三种新型氟喹诺酮类药物治疗性病性尿道 (生殖道 )炎的临床效果。方法　 14 6例性病性尿道 (生殖道 )炎病人按就诊顺序随机分为三组 :左氧氟沙星组 80例 ,用盐酸左氧氟沙星注射液治疗 ;氧氟沙星组 36例 ,用氧氟沙星注射液治疗 ;氟罗沙星组 30例 ,用氟罗沙星注射液治疗。三组疗程均为 7～ 14d。结果　左氧氟沙星组治愈率 (86 2 5 % )高于氧氟沙星组 (6 1 11% )和氟罗沙星组 (6 3 33% )。不良反应发生率 (7 5 0 %、11 11%、16 6 7% )三组间差异无显著意义 (P >0 0 5 )。结论　三种新型氟喹诺酮类药物治疗性病性尿道 (生殖道 )炎均安全有效 ,左氧氟沙星优于氧氟沙星和氟罗沙星。     

Genotoxicity evaluation of low doses of clodinafop-propargyl to the silkworm Bombyx mori using alkaline single-cell gel electrophoresis

In the present study, DNA damage caused by clodinafop-propargyl was evaluated in silkworm, Bombyx mori, by the alkaline single-cell gel electrophoresis (SCGE). The second, fourth and fifth instar larvae of silkworm were exposed to clodinafop-propargyl by oral feeding with mulberry leaves treated using the different concentration of 30, 60, 120, 240, 480mgL(-1), respectively. The results showed that comet percentage, the head DNA percentage, tail DNA percentage, tail length, tail moment and olive moment of the five tested groups were significantly different from the controlled group (P<0.01). A statistically significant (olive tail moment, P<0.01) dose-dependent increase in DNA damage was observed in silkworm. In addition, the significant dose-dependent reduce in percentage of cocooning and pupating was found in the second instar larvae of silkworm exposed to clodinafop-propargyl. To our knowledge, this was the first report describing the genotoxicity assessment of pesticide using silkworm by the alkaline SCGE.     

家蚕发育恒定温区研究

在不同的环境温度下测定五龄幼虫体温与环境温度之差,发现环境温度小于30℃时,蚕体温高于环境温度。环境温度越低,差数越大;但环境温度低于20℃时,差数反而缩小。当环境大于30℃时,蚕体温低于环境温度,温度越高,差效越大。各环境温度下幼虫体温与其之差的绝对值随五龄天数的增加而减少。因此认为家蚕具有一定的体温主动调节能力和一生理适温点(供试品种在30℃左右)。这种调节能力龄初和龄中较强,龄末最弱,测定家蚕品种的生理适温点,可作为确定其饲育适温的重要参考指标。     

Effects of molecular mass and hydrophobicity on transport rates through non-specific pathways of the silkworm larva midgut

We previously reported that therapeutic drug effects in the silkworm infection model are largely influenced by midgut permeability. In this report, we describe the effects of drug molecular mass and hydrophobicity on transport through the silkworm larva midgut membrane. Hydrophilic compounds with a molecular mass of greater than 400Da did not permeate the silkworm larva midgut, and the hydrophobicity of similar-sized compounds had positive effects on the transport rate. Furthermore, we compared transport rates through the midgut membrane between cefcapene sodium (CFPN-Na) and cefcapene pivoxil (CFPN-PI), which is a CFPN-Na prodrug. The in vitro transport rate of CFPN-PI was three times faster than that of CFPN-Na. Moreover, when CFPN-PI and CFPN-Na were injected into the living silkworm larva midgut, CFPN-PI appeared rapidly in the haemolymph, whereas CFPN-Na did not. The 50% effective dose (ED50) of CFPN-PI administered via the midgut was one-sixth that of CFPN-Na. These findings suggest that the general features of the non-specific transport route are similar between silkworm larvae and mammals.     

非甾体抗炎药物及其作用机理进展

通过对大量文献的调研 ,总结了花生四稀酸代谢的主要途径 ,以及代谢产物与炎症发生和发展的关系。综述了新结构类型抗炎镇痛药或化合物的主要特点。介绍了环氧化酶公知的两种亚型COX 1与COX 2。指出了COX 2是非甾体抗炎药物治疗作用的靶酶。预见了COX 2抑制剂 ,CO/ 5 LO双重抑制剂 ,特异性 5 LO抑制剂应是未来抗炎药研究的重点方向     

Potential mediators, moderators, or independent effects in the relationship between parents' former and current cigarette use and their children's cigarette use

Research consistently has shown that cigarette use by adolescents is related to their parents' use and to particular characteristics of the family environment, but few studies have examined the linkages between parents' smoking behavior and other family characteristics to explain adolescents' smoking. In this study, we tested mediator, moderator, and independent models for their ability to characterize the relationship between parents' and their children's smoking. A sample of 719 matched pairs of parent (usually mother) and child was used. Respondents were part of an ongoing randomized evaluation of the Drug Abuse Resistance Education (DARE) Project in Illinois, and the subset of data used in these analyses was collected in 1991, when the youths were in the sixth or seventh grades. Results of logistic regression provided the greatest support for the independent model, which suggests that the effects of parents' smoking and familial characteristics on adolescents' smoking are not linked. Results also supported those found by other researchers by showing that parents' former smoking is associated with adolescents' current smoking. Significant family characteristics were family disunion and parents' awareness of their child's activities. These results suggest, in part, that children at any age may have the capability of storing memories of their parents' smoking, memories that influence their own smoking; also, characteristics of the family environment, independent of parents' smoking behavior, have an effect on adolescents' smoking. Prevention implications and recommendations are also discussed.     

Children's perceptions of parental drinking: the eye of the beholder

OBJECTIVE: Children learn about alcohol and about how to drink through modeling experience, in part. Modeling is typically studied by asking parents to describe their drinking behavior. However, children's perception of parents' drinking may differ from the way parents describe it. This study examined the degree to which children's perceptions and parents' reports agreed. METHOD: A sample of 177 grade-school children and their parents was drawn from a public school in Kentucky. Children completed questionnaires inquiring about their perceptions of the quantity, frequency and the positive and negative consequences of their parents' drinking. Their parents completed similar questionnaires describing their own drinking and its consequences. RESULTS: As hypothesized, first and second grade children's perceptions of parents' drinking were unrelated to parents' self-reports: Most of these children perceived their parents as nondrinkers even though parents reported drinking. Also as hypothesized, children's perceptions and parents' reports were significantly correlated for third through sixth grade students. However, there was a great deal of reliable, but unshared variance between these older children's perceptions and parents' reports. Children's perceptions and parents' reports were consistently quite different, even when both child and parent described the parent as a drinker. CONCLUSIONS: Studies of modeling influences on children regarding drinking should assess children's perceptions of their parents' behavior rather than parents' self-reports.     

The effects of maternal Cd on the metallothionein expression in tilapia (Oreochromis mossambicus) embryos and larvae

The purpose of this study was to identify the factor(s) which would enhance the Cd resistance as assessed by the metallothionein (MT) expression in tilapia larvae. Larvae were collected from parents that were pretreated respectively with Cd or saline. At the end of the 12-week experiment, the hepatic MT and Cd contents in the breeding female fish were recorded. Our results indicated that a significant relationship between Cd and MT contents can be found in the offspring from the parent fish treated with Cd. However, the higher Cd resistance, Cd contents, and MT expression were limited to those larvae from parent fish bred within 4 weeks of the injection. By week 12, the Cd-treated fish still contained high levels of MT in their hepatic tissues. However, the MT and Cd contents in the larvae from these adult fish were not significantly different from those from the controls. In summary, we suggest that the higher Cd resistance of larvae from the egg stage was a result of the Cd contamination of the parent female, as evidenced by an increase in MT expression induced in tilapia embryos and larvae.     

家蚕对2型糖尿病大鼠脂代谢及脂肪细胞因子的影响

目的观察家蚕对2型糖尿病大鼠脂代谢及脂肪细胞因子的影响,探讨其对治疗糖尿病的作用机制。方法以高热量饮食喂养SD大鼠6周加小剂量链脲佐菌素(STZ)建立2型糖尿病大鼠模型,采用随机数字表法分为模型对照组,吡格列酮组,家蚕高、中、低剂量组,共5组,测定其空腹血糖(FBG)、空腹血胰岛素(FINS)、肿瘤坏死因子(TNF)-α、游离脂肪酸(FFA)、脂联素(APN)水平。结果家蚕中、低剂量组及吡格列酮组FBG均有不同程度的降低,与模型对照组差异有统计学意义(P<0.01)。家蚕各剂量组和吡格列酮组大鼠FINS、TNF-α、FFA均有不同程度的下降,与模型对照组大鼠相比差异有统计学意义(P<0.05或P<0.01)。家蚕中、低剂量组和吡格列酮组脂联素与模型组相比显著升高(P<0.01)。结论家蚕可通过调节2型糖尿病大鼠脂代谢及脂肪细胞因子水平,改善其胰岛素抵抗状态,为家蚕的临床应用提供了实验依据。     

Studies on Bacillus thuringiensis H-14 strains isolated in Egypt. VII. Toxicity to insecticide resistant and susceptible strains of mosquitoes

Two strains of Bacillus thuringiensis H-14 (M1 and S128) isolated in Egypt were bioassayed in the laboratory against various insecticide-susceptible and -resistant mosquito species and strains. The results for both bacterial strains tested against Aedes (4 strains), Culex (4 strains), and Anopheles (7 strains) larvae indicate a wide spectrum of larvicidal activity within the Culicidae. Generally, fourth instar larvae of the Aedes and Culex strains were found to be more susceptible than third instar larvae of Anopheles strains. In addition, mosquito strains within the same species that have different geographical origins and/or resistance patterns to residual insecticides were found to have different susceptibilites to the tested preparations. No apparent relationship was found between resistance to insecticides in these mosquito strains and their susceptibility to the tested preparations of B. thuringiensis H-14. These data indicate that B. thuringiensis H-14 could be of potential use against insecticide-resistant vector populations in integrated disease-control programs. © 1994 by John Wiley & Sons, Inc..     

High-level expression of human butyrylcholinesterase gene in Bombyx mori and biochemical-pharmacological characteristic study of its product

The human butyrylcholinesterase (BChE, EC 3.1.1.8) gene was highly expressed in Bombyx mori using baculovirus vector, and the biochemical-pharmacological properties of its product were studied. BChE cDNA was cloned into transfer vector pBn96 and co-transfected with wild-type Bombyx mori nucleopolyhedrovirus (BmNPV) DNA into BmN cells. The recombinant virus with the highest enzyme activity was sorted out and purified. Once the BmN cells or silkworm larvae had been infected with the recombinant virus, recombinant human BChE (rhBChE) could be secreted into the culture medium or the hemolymph of the larvae at levels of 1.5 mg x L(-1) and 35 mg x L(-1), respectively. Western blot and enzymatic staining of the electrophoresis gel of non-denatured protein showed that rhBChE manifested similar antigenicity and enzyme activity to native human BChE (nhBChE). The production of rhBChE in the hemolymph was 23-fold higher than that in BmN cells and about 280-fold that in Chinese hamster overy cells (125 microg x L(-1)). This is the first report of human BChE expression in silkworm with the highest level of yield so far. rhBChE was highly similar to nhBChE in respect to substrate affinity, inhibitor sensitivity, and reactivity of the inhibited enzyme. It is suggested that rhBChE functions as well as nhBChE and has potential practical value.