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1.
Abstract  SV1 was observed to have obvious synergism and could delay housefly ( Musca domestica vicina ) resistance development to Dipterex. The penetration rates of Dipterex through housefly cuticle were determined in a susceptible and two resistant strains. The results indicated that the penetration in the resistant housefly strains was obviously slower than in the susceptible one. The penetrating rate of SV1+ Dipterex (in mixture) was higher than that of Dipterex. The penetration reduction in resistant houseflies may be an important factor in bringing forth resistance. The increase of the penetrating rate of Dipterex and the decrease of its metabolic rate are regarded as the important mechanisms of SV1 synergism to Dipterex.  相似文献   
2.
不同细菌对家蝇幼虫抗菌蛋白/肽的诱导效应   总被引:4,自引:0,他引:4  
利用抑菌圈测量法和毛细管电泳研究、比较不同细菌对家蝇Musca domesticaL.幼虫抗菌蛋白/肽的诱导效应。结果表明,家蝇幼虫受细菌诱导后抗菌活性比对照都有不同程度的增加,同时不同细菌诱导表达样品对于相应的诱导菌均表现很高的抗菌活性。毛细管电泳图谱表明鼠伤寒沙门氏菌Salmonella typhimurium50013诱导后抗菌蛋白/肽表达强度增加了50倍,其它细菌诱导后抗菌蛋白/肽表达强度增加了1~40倍。与G+细菌相比,G-细菌具有更强的诱导效应。结论:家蝇幼虫对不同的细菌刺激有特异性反应,即不同细菌诱导抗菌蛋白/肽的强度、种类和数量都不一致。  相似文献   
3.
During vitellogenesis in Musca domestica, a major hemolymph protein, in addition to vitellogenin, appears preferentially in females. This protein is synthesized by the adult fat bodies, secreted into the hemolymph, and is not taken up by the ovaries during vitellogenesis. We have designated this protein nonvitellogenic female protein (NVFP). It is composed of only one type of polypeptide (Mr=70,000) and occurs in two different forms. Synthesis of NVFP is induced by a protein diet, attaining maximum concentrations in females at the middle of the gonotrophic cycle. In males its maximum concentration never surpasses 10% of the concentration in females. The quantitative variation of the NVFP is cyclic and coincident with the gonotrophic cycles of Musca domestica.  相似文献   
4.
Abstract The objective of this study was to elucidate the effects of cadmium on housefly, Musca domestica. It is suggested that of cadmium in low concentrations of had little influence on growth and development of housefly. Cadmium was mainly distributed in the digestive tracts of housefly larvae, where the cadmium content was higher than that of other parts. During the metamorphosis of housefly the change trend of the cadmium content was very apparent. The cadmium content increased gradually in larval period, whereas it decreased significantly after polarization. Until the sixth day after emergence, only negligible cadmium was left in adult housefly. All these results demonstrated that the response of housefly to cadmium is an evolution adaptation in natural selection.  相似文献   
5.
Our cytological analysis revealed high proportions of XX males in some housefly populations of Turkey. In contrast to earlier findings in Europe, on the British Islands, and in Japan, the XX male frequency in Turkey was not correlated to the geographical latitude. In general, the frequency of XX males was lower in populations from the central and eastern Anatolian highlands than from coastal regions, demonstrating a correlation of the sex-determining mechanisms to geographical altitude and perhaps other geographical characteristics.  相似文献   
6.
Summary The cell-body layer of the lamina ganglionaris of the housefly, Musca domestica, contains the perikarya of five types of monopolar interneuron (L1–L5) along with their enveloping neuroglia (Strausfeld 1971). We confirm previous reports (Trujillo-Cenóz 1965; Boschek 1971) that monopolar cell bodies in the lamina form three structural classes: Class I, Class II, and midget monopolar cells. Class-I cells (L1 and L2) have large (8–15 m) often crescentshaped cell bodies, much perinuclear cytoplasm and deep glial invaginations. Class-II cells (L3 and L4) have smaller perikarya (4–8 m) with little perinuclear cytoplasm and no glial invaginations. The midget monopolar cell (L5) resides at the base of the cell-body layer and has a cubshaped cell body. Though embedded within a reticulum of satellite glia, the L1–L4 monopolar perikarya and their immediately proximal neurites frequently appose each other directly. Typical arthropod (-type) gap junctions are routinely observed at these interfaces. These junctions can span up to 0.8 m with an intercellular space of 2–4 nm. The surrounding nonspecialized interspace is 12–20 nm. Freezefracture replicas of monopolar appositions confirm the presence of -type gap junctions, i.e., circular plaques (0.15–0.7 m diam.) of large (10–15 nm) E-face particles. Gap junctions are present between Class I somata and their proximal neurites, between Class I and Class II somata and proximal neurites, and between Class II somata. Intercartridge coupling may exist between such monopolar somata. The cell body and proximal neurite of L5 were not examined. We also find that Class I and Class II somata are extensively linked to their satellite glia via gap junctions. The gap width and nonjunctional interspace between neuron and glia are the same as those found between neurons. The particular arrangement and morphology of lamina monopolar neurons suggest that coupling or low resistance pathways between functionally distinct neurons and between neuron and glia are probably related to the metabolic requirements of the nuclear layer and may play a role in wide field signal averaging and light adaptation.  相似文献   
7.
环腺苷酸(cAMP)可在神经传递物刺激腺苷酸环化酶的作用下产生,而坏腺苷酸又可促成神经传递物的产生.用溴氰菊酯(deltamethrin)处理家蝇后,发现酪胺大量增加,主要由于酪氨酸脱羧酶受到诱导、活性增高所致.处理后一小时,cAMP也有增加,并与酶活性的增加相平行,但酪氨酸脱羧酶活性增高的曲线与cAMP量增加的曲线,实际上并不平行,因酪氨酸脱羧酶的活性是先增加,然后下降,而cAMP的量则是在开始时有一个小的下降,接着一直上升,而此时酶的诱导已下降,cAMP含量在诱导开始时出现下降的原因尚不明,可能与环鸟苷酸(cGMP)有关.但随后的上升显然是由于酪胺或章鱼胺的增加所造成.目前已证实,酪胺可经β-羟化作用形成章鱼胺,后者再刺激章鱼胺受体,而使腺苷酸环化酶活化,产生大量的cAMP.酪胺本身也可能就是章鱼胺受体的激活剂.  相似文献   
8.
采用化学分析和动物实验的方法对冷冻干燥、微波干燥和低温干燥的蝇蛆粉进行了营养评价。结果表明,3种干燥方法不影响蝇蛆粉的粗蛋白和灰分含量,但微波干燥蝇蛆粉的脂肪含量显著降低;氨基酸分析显示,冷冻干燥蝇蛆粉的氨基酸总含量>微波干燥的蝇蛆粉>低温干燥的蝇蛆粉,而3种方法干燥的蝇蛆粉EAA/TAA均等于或大于41%,说明干燥所得的蝇蛆粉均属优质蛋白。另外,与FAO/WHO参考模式值相比,冷冻干燥蝇蛆粉的必需和半必需氨基酸总量明显高于FAO/WHO参考模式值,微波干燥的蝇蛆粉与FAO/WHO参考模式值相当,而低温干燥的蝇蛆粉中必需与半必需氨基酸含量显著低于FAO/WHO参考模式值,说明微波干燥及低温干燥会破坏蝇蛆中的某些必需或半必需氨基酸。动物实验结果表明,冷冻干燥的蝇蛆粉在动物体内被吸收利用的程度最高,其次是酪蛋白,再次是低温干燥的蝇蛆粉,而微波干燥的蝇蛆粉被动物吸收利用的程度最低。  相似文献   
9.
从饲料用麦麸中分离出的12种细菌均能支持无菌家蝇Musca domestica L.幼虫在胰化酪蛋白大豆卵黄琼脂(TrypticaseSoy EggYolkAgar,TSEYA)培养基中完成整个生长发育过程。1)幼虫在接种香味类香味菌Myroidesodoratimimus的TSEYA培养基中生长时间最短,仅需97.61±1.14h;2)幼虫在接种醋酸钙不动杆菌Acinetobacter calcoaceticus的TSEYA培养基中的化蛹率可达到86.81%;3)从接种嗜水汽单胞菌Aeromonas hydrophila的TSEYA培养基中得到的蝇蛹重量最高,达到20.15±0.23mg/个;4)除铜绿假单胞菌Pseudomonasaeruginosa饲养的家蝇羽化率较低(60.87%)外,其余各种细菌饲养的羽化率在84.33%~97.47%之间。此外,枯草芽孢杆菌Bacillus subtilis、香味类香味菌、聚团肠杆菌Enterobacter agglomerans以及成团肠杆菌Pantoeaagglomerans可作为单一营养来源支持幼虫完成整个生长发育过程。对枯草芽孢杆菌、金黄色葡萄球菌Staphylococcusaurous、成团肠杆菌、大肠杆菌Escherichiacoli、奇异变形杆菌Proteusmirabilis以及香味类香味菌中各种营养成分进行分析,结果发现,6种细菌均能提供大量的维生素如(0.105~1.08g/kg)。在氨基酸方面,香味类香味菌和枯草芽孢杆菌中的10种昆虫必需氨基酸含量与总氨基酸含量之比(Essential amino acid/Totalaminoacid,EAA/TAA)最高,而金黄色葡萄球菌最低。这个比例与蛹重呈正相关(p=0.031)。在脂肪酸相对含量方面,金黄色葡萄球菌具有最高的饱和脂肪酸含量(76.38%),香味类香味菌含有56.79%的不饱和脂肪酸,而枯草芽孢杆菌则具有最高的支链脂肪酸含量(42.16%)。  相似文献   
10.
研究重金属镉对家蝇生长发育的影响,以及镉在家蝇变态过程中的代谢。结果表明:低浓度的Cd^2 对家蝇的生长分育几乎没有什么影响,而高浓度的Cd^2 则影响家蝇卵孵化率,幼虫相对存活率,化蛹率,羽化率,百头幼虫理和百头蛹重。进入家蝇幼虫体内的Cd^2 主要分布在消化道,其次是体壁,脂肪体和血淋巴中含量很少。在家蝇变态过程中,Cd^2 的含量变化趋势十分明显:幼虫期Cd^2 逐渐累积,化蛹后Cd^2 含量大幅度下降,羽化后的第6天,成虫体内只剩下极微量的Cd^2 。这些结果表明家蝇对环境中重金属镉的反应是一种在自然选择过程中形成的高度的进化适应。  相似文献   
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