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41.
Abstract.
- 1 In field cage and field tests, female Mediterranean fruit flies, Ceratitis capitata (Wiedemann), in trees alighted in significantly greater numbers upon sticky-coated (non-odour-emitting) kumquats, Fortunella japonica, that were in the vicinity of odorous natural proteinaceous food (bird faeces) or synthetic food odour than on similar kumquats distant from bird faeces or synthetic food odour.
- 2 In field cage tests, oviposition in non-sticky kumquats nearby bird faeces was significantly greater than in non-sticky kumquats distant from bird faeces.
- 3 In field tests, medflies laid significantly more eggs in host kumquat and non-host hawthorn, Crataegus mollis, fruit adjacent to bird faeces and synthetic food odour than in fruit of these types distant from food-type stimuli.
- 4 These findings suggest that odour of natural food of medflies could lure flies to plants whose fruit emit little or no attractive odour and are not permanent hosts but which are nonetheless susceptible to egg-laying and larval development, resulting in temporary expansion of host range.
42.
43.
脊髓中血管紧张素Ⅱ的释放及其抗电针镇痛 总被引:9,自引:0,他引:9
本文采用放射免疫分析方法测定不同频率电针引起大鼠脊髓液中血管紧张素Ⅱ(AⅡ)免疫活性(ir)的变化,并观察阿片受体在其中起的作用。结果表明:(1)2Hz电针时大鼠脊髓灌流液中AⅡ-ir减少20%,但无统计学意义;15Hz电针使满足流液中AⅡ-ir降低62%(P〈0.01);100Hz时AⅡ-ir增加60%(P〈0.05)。(2)脊髓蛛网膜下腔(i.t.)注射阿片受体拮抗剂纳洛酮后,15HZ电针反使 相似文献
44.
本文记述采自中国北方滨海地区植绥螨二新种及二新纪录种。单毛盲走螨Typhlodromus,monosetus sp.nov.采自吉林长自山;凹胸盲走螨T.concavus sp.nov.采自山东省泰山。山葡萄钝绥螨Amblyseius vineaticus Wainstein及柞钝绥螨A.quaesitus Wainsteia et Begliarov均采自长白山,为中国新纪录。首次描述千山盲走螨T.qianshanensis Wu雄螨。 相似文献
45.
尺蛾科是鳞翅目中的第二大科,全世界已知约12,000种。由于其种类众多,幼虫形态亦表现为多型多样。现今一般昆虫学书籍,对于本科幼虫形态特征,通常概括为腹足2对,而没有更多的叙述。但由于桦尺蛾亚科(Brephinae)及其它一些属的幼虫腹足并非两对,因此,这种过于简略的概括,将使一些种的幼虫在科的鉴定上造成困难。 相似文献
46.
Wistar rats were inoculated with purified YWK-I antibody.The anti-idiotypic antibodies were isolated from rat sera by successive passage over affinity chromatography columns of YWK-I mAb and normal mouse Igs.Specificity of anti-Id antibody was established by ELISA.The 84kD protein inhibited the binding of anti-Id to YWK-I mAb,but failed to repress antibody against normal mouse Ig binding to YWK-I mAb.In competitive inhibition assay,84kD protein had shown the ability to compete with anti-Id binding to YWK-I mAb in a dose-dependent manner.Crude sperm extract showed a lower competitive ability.No effect was found with the irrelevant 36kD sperm protein.The antisera from the Balb/C micr immunized with AId contained Ab3 that reacted with 84kD sperm protein.The binding of anti-Id to YWK-I mAb was inhibited by Ab3 in a dose-dependent fashion and Ab3 was shown to be able to induce human sperm agglutination.These results indicate that anti-Id which may mimic an epitope of the 84kD protein could be exploited as an antigen to raise antibodies against sperm protein. 相似文献
47.
家兔蓝斑复合核区微量注入去甲肾上腺素能激动剂和拮抗剂对呼吸和血压的效应 总被引:1,自引:0,他引:1
于麻醉家兔脑桥蓝斑复合核(LC)区微量注入去甲肾上腺素溶液(0.1mol,1或2μl),引起肺通气量增加和动脉血压升高。上、下丘间全离断脑干或横断中脑被盖及其背侧结构,不能消除此效应。LC 区同一点施加电刺激引起相同效应。LC 区注入α-受体阻断剂酚妥拉明(0.1mol,2μl)、妥拉苏林(0.1mol,2μl)或 α-受体激动剂氯压啶(0.02mol或0.1mol,2μl),使肺通气量明显减少,而对血压影响不大。本结果提示LC及附近被盖区的去甲肾上腺素能传人纤维可通过 α-受体调制该区的植物性机能。 相似文献
48.
氨基酸对蟾蜍卵母细胞膜电位的影响及其作用机制 总被引:1,自引:0,他引:1
本文采用微电极细胞内记录方法观察了23种氨基酸处理后蟾蜍卵母细胞膜电位的变化。丙氨酸、亮氨酸和赖氨酸可致膜电位去极化和膜K~+通透性降低,而色氨酸可致膜电位超极化和膜K~+通透性增加。其他19个氨基酸未见对膜电位有何作用。丙氨酸、亮氨酸和赖氨酸于引起去极化同时,还使卵母细胞孕酮含量成倍增加和卵母细胞趋于成熟。这些作用可被1mmol/L 丁酰 cAMP(db-cAMP)或 50μmol/L 雌二醇完全阻断。另一方面,色氨酸能阻断孕酮(10μmol/L)所致的去极化,但对 db-cAMP 所致的超极化无作用。本文讨论了氨基酸和甾类激素对卵母细胞成熟的调节作用。 相似文献
49.
Growth induction of hepatic stimulator substance in hepatocytes through its regulation on EGF receptors 总被引:8,自引:0,他引:8
The cytosolic liver-specific growth factor-hepatic stimulator substance (HSS) has been shown to be able to amplify the rat hepatkocyte proliferation responded to BGF.In order to get more insight into the mechanism,the regulatory effect of HSS on EGF-receptor (EGF-R) and the receptor phosphorylation at molecular level was studied.HSS partially purified from weanling rat liver was given to cultured hepatocytes and its influence on EGF-R specific binding and internalization as well as mRNA expression were investigated.The results showed that preincubation of hepatocytes with HSS could lead to an increase in [^125I]-EGF binding to its receptors and inhibit EGF-induced receptor down-regulation.Furthermore,the overexpression of EGF-R mRNA stimulated by HSS was seen during 2-12 h after the incubation.Additionally,it was demonstrated with human hepatoma SMMC-7721 cells in Western blot that the EGF-R expression and the receptor autophosphorylation were increased with dose/timedependency after HSS treatment.These results strongly suggest that the mechanism of HSS action on hepatocyte growth might be related to its modulation on EGF-R and receptor-mediated signaling transfuction. 相似文献
50.
七星瓢虫卵子发生的观察 总被引:7,自引:0,他引:7
对七星瓢虫(Coccinella septempunctata L.)卵子发生过程进行了组织学、细胞学观察及阶段划分,并与取食人工饲料的瓢虫进行对比。卵母细胞仅出现在幼虫期。蛹期已分化为卵母细胞与营养细胞。成虫期卵子发生可以明显的分为卵母细胞分化、卵母细胞营养及卵母细胞卵黄形成三个时期,并分为9个阶段。第1阶段:卵母细胞位于卵原区,进行第一次减数分裂的前期。第2阶段:卵母细胞位于颈区,开始增大,出现了营养索,DNA呈明显的孚尔根正反应。第3阶段:卵母细胞形成卵泡囊并进入生长区,核增大成胚泡。第4阶段:胚泡移至卵质周缘,卵质中RNA丰富,滤泡细胞立方形。第5阶段:胚泡内核仁增大、分枝并释放核仁小体进入卵质。第6阶段:营养索消失,滤泡细胞扁平并出现空位,卵黄形成开始。第7阶段:卵黄球形成逐渐充满卵质,胚泡膜逐渐消失。第8阶段:胚泡消失,滤泡细胞开始分泌卵壳。第9阶段:卵发育完成,经过上皮塞进入输卵管。取食人工饲料瓢虫的卵子发生过程显著缓慢,发育中的卵母细胞致量少,滤泡细胞及卵黄分布均不正常。 相似文献