首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
释放花绒寄甲防治天牛已成为重要手段,而繁殖花绒寄甲时,接种花绒寄甲幼虫到大麦虫蛹体时,控制合适的接种量是提高花绒寄甲繁殖数量和质量的关键技术。本研究通过在替代寄主上人工接种不同数量的花绒寄甲幼虫,观察其发育情况及其子代数量、质量等指标,明确最佳接种量。结果表明:随着接种量的增加,花绒寄甲幼虫历期和蛹历期明显缩短,其中接种4头/个和6头/个,幼虫历期为13 d,蛹历期为33 d,而接种14头/个和16头/个时,幼虫历期短于12 d,蛹历期明显缩短为28~29 d。花绒寄甲结茧数随接种量增加而增加,接种数为16头/个时,结茧数最多,接近7个。花绒寄甲结茧率随着接种量增多而降低,4头/个时,结茧率最高为72.3%。接种量对花绒寄甲子代个体数量和大小均有显著影响,其中接种8头/个时,羽化数平均为4.3头,显著高于接种4头/个(羽化数平均为2.8头),明显低于接种16头/个(羽化数平均为6.9头)。接种量为4头/个和6头/个时,子代成虫个体最大,单头重平均每头可达0.035 g,接种量为8头/个时,成虫单头重平均每头0.032 g左右,接种量达到16头/个时,单头重最轻,为0.023 g。对花绒寄甲羽化率无显著影响,7个处理下子代羽化率均较高,平均在94.4%~100%。接种量越少,更利于花绒寄甲的生长发育,当接种量为4头/个时,花绒寄甲成虫发育最好,其子代个体最大,但子代数较少。因此,利用大麦虫蛹繁育花绒寄甲种虫时,最佳接种量为4头/个,而需要规模化繁育花绒寄甲作为天敌使用时,综合考虑子代数量和质量以及经济成本,最佳接种量为8头/个。  相似文献   

2.
A variety of microorganisms, including gram-negative and gram-positive eubacteria, actinomycetes, yeasts, and filamentous fungi, were tested for their sensitivity to cadmium (Cd). In general, the actinomycetes were more tolerant to Cd than were the eubacteria; gram-negative eubacteria were more tolerant to Cd than were gram-positive eubacteria. The period of exponential growth of the eubacteria and actinomycetes was extended in the presence of Cd. Wide extremes in sensitivity to Cd were noted among the fungi; there was no correlation between the class of fungus and tolerance to Cd. Fungal sporulation was more sensitive to Cd than was mycelial growth, as spore formation was inhibited at Cd concentrations that were noninhibitory to mycelial proliferation. The toxicity of Cd to the eubacteria, actinomycetes, and fungi appeared to be pH dependent, as toxicity was generally potentiated at pH 8 or 9.  相似文献   

3.
Rational position of voriconazole in the treatment of oncologic inpatients was shown and the criteria of its use in the algorithms of the therapy and prophylaxis of nosocomial fungal infections were developed. The clinical trial enrolled 50 patients with oncologic pathologies. The patients were divided into two groups of possible invasive candidiasis risk. The patients of one group were treated with fluconazole (Diflucan) and those of the other group were treated with voriconazole (Vifend). The spectrum of the hospital fungal flora was determined and susceptibility of 310 clinically important opportunistic fungi was investigated. All the isolates of Candida albicans and C.tropicalis were susceptible to amphotericin B, fluconazole and voriconazole and 79 and 50% of the isolates were susceptible to intraconazole respectively. As for the C.krusei isolates, 67% was susceptible to amphotericin B, 50% was susceptible to fluconazole, 100% was susceptible to voriconazole and none of the strains was susceptible to intraconazole. By the clinical efficacy voriconazole was superior to fluconazole and comparable with amphotericin B, while superior to it by the number of the side effects and by the cost of the treatment course. It was concluded that voriconazole should be considered as the main agent in the antifungal therapy of oncologic patients.  相似文献   

4.
HYMENOLEPIS DIMINUTA: adults were killed and fixed in fully extended positions, and the total lengths of the strobilae, numbers of proglottids, and distances of proglottids along the strobilae were determined. The relationship of proglottid number to distance along the strobila was exponential. Beginning at proglottid 100 (P100), the lengths and widths of proglottids at 100 proglottid intervals were determined, and the surfaces areas were calculated. The relationships of proglottid length and width to proglottid number were linear, but the relationship of proglottid number to surface area (SA) was exponential. The volumes of proglottids were calculated, and the relationship of volume (V) to proglottid number was exponential. The relationship of surface area to volume ratio (SAVR) to proglottid number was exponential; at the anterior end of the worm (P100), the SAVR was 14.6, while at the posterior end of the worm (P1300) the ratio was 4.2. A single exponential equation describing the relationships among proglottid number, SA, and V was derived.  相似文献   

5.
钝顶螺旋藻是一种丝状多细胞蓝藻。经透射电源观察证实,细胞的核区无核膜,核仁,细胞质内无线粒体、叶绿体、高尔基体等细胞器分化。  相似文献   

6.
The morphological, physiological, and biochemical characteristics of twelve "Pasteurella" piscicida strains isolated from white perch and yellowtail are described and the present uncertain taxonomic status of the organisms is discussed. The organisms isolated were gram-negative rods showing bipolar staining and pleomorphism. No spores or flagella were observed. They were non motile and viscid colonies were formed. Growth was observed in a temperature range of 20 to 30 C and the salinity range of growth was between 0.5% and 4.0%. They were aerobic and facultative anaerobic. Oxidase and catalase were produced. Nitrates were not reduced to nitrites. Lysine and ornithine decarboxylases were not produced but arginine dihydrolase was produced. The egg yolk reaction was positive. Tween 80 and tributyrin were decomposed. Phosphatase was produced. Beta hemolysis was revealed on a medium containing defibrinated blood from chickens or carp but not from mammals. Methyl red and Voges-Proskauer tests were positive, and acetoin was produced from 2,3-butanediol. Glucose was fermented without gas production. Acid was produced from fructose, mannose, galactose, sucrose, maltose, dextrin and glycerol. These organisms differed from all other members of the genus Pasteurella with respect to nitrate reduction, arginine dihydrolase, Voges-Proskauer and methyl red tests. The formation of viscid colonies and inability to grow in a medium without sodium chloride or at 37 C were additional characteristics of these organisms.  相似文献   

7.
依据姜黄属(Curcuma)花卉育种目标,对16份姜黄属植物的11个数量性状及7个质量性状进行因子和聚类分析评价。结果表明,姜黄属植物表型性状复杂多变,供试材料数量性状变异系数介于26.70%~95.44%,叶片主脉绿色,上苞片藕粉或玫红色,晕斑绿色,唇瓣紫色和旗瓣白色为姜黄属典型表型性状。主成分分析表明,9个重要观赏性状归于3个主成分中。根据表型性状各主成分进行聚类分析,供试16份种质被分为三大类群,第Ⅰ类群11个品种均为姜荷花(Curcuma alismatifolia),其中‘清迈粉’的上苞片面积最大,观赏性最突出,但株型偏小。第Ⅱ类群4个品种,花型花色极具特色,株型更大,抗性强,以所罗门姜黄(C. soloensis)表现最优。第Ⅲ类群的女皇郁金(C. petiolata)生长势最为强健。在三个类群之间开展杂交育种有望获得兼具观赏性和生长势的后代。  相似文献   

8.
总结脑膜炎败血伊丽莎白菌感染患儿的临床特点,以期提高临床诊治水平。收集中山市博爱医院2010年1月至2020年12月收治的3例脑膜炎败血伊丽莎白菌引起的脑膜炎患儿临床资料,结合相关文献进行总结分析。结果显示,3例患儿脑脊液中培养出脑膜炎败血伊丽莎白菌,其中2例血培养为同种细菌。3例患儿均为足月顺产,2例为新生儿期发病,1例为出生后35天发病,起病前均未发现致病高危因素。患儿以发热为主要起病表现,无抽搐及脑膜刺激征表现。3例患儿外周血常规白细胞总数、C反应蛋白、降钙素原均升高;脑脊液潘氏试验均为阳性,伴脑脊液白细胞数增高,脑脊液蛋白明显增高,脑脊液葡萄糖降低。头颅磁共振成像(magnetic resonance imaging,MRI)或电子计算机断层扫描术(computer tomography,CT)可见脑膜强化、软脑膜增厚、脑外间隙增宽,均无脑实质受累。3例检出菌株的药敏结果表现出高度一致性,均提示对环丙沙星、哌拉西林/他唑巴坦、左氧氟沙星、复方新诺明敏感。2例患儿以环丙沙星治疗,1例患儿以美罗培南联合万古霉素治疗。其中1例治愈,2例临床症状好转后出院。经电话随访,3例患儿一般情况尚可,无生长发育异常。本病例报道提示,脑膜炎败血伊丽莎白菌脑膜炎主要见于新生儿期,以发热起病为主要表现,该菌对儿科常用抗菌药物多显示体外耐药,对喹诺酮类药物敏感。  相似文献   

9.
Phylogenetic relationships within Celastraceae were inferred using a simultaneous analysis of 61 morphological characters and 1123 base pairs of phytochrome B exon 1 from the nuclear genome. No gaps were inferred, and the gene tree topology suggests that the primers were specific to a single locus that did not duplicate among the lineages sampled. This region of phytochrome B was most useful for examining relationships among closely related genera. Fifty-one species from 38 genera of Celastraceae were sampled. The Celastraceae sensu lato (including Hippocrateaceae) were resolved as a monophyletic group. Loesener's subfamilies and tribes of Celastraceae were not supported. The Hippocrateaceae were resolved as a monophyletic group nested within a paraphyletic Celastraceae sensu stricto. Goupia was resolved as more closely related to Euphorbiaceae, Corynocarpaceae, and Linaceae than to Celastraceae. Plagiopteron (Flacourtiaceae) was resolved as the sister group of Hippocrateoideae. Brexia (Brexiaceae) was resolved as closely related to Elaeodendron and Pleurostylia. Canotia was resolved as the sister group of Acanthothamnus within Celastraceae. Perrottetia and Mortonia were resolved as the sister group of the rest of the Celastraceae. Siphonodon was resolved as a derived member of Celastraceae. Maytenus was resolved as three disparate groups, suggesting that this large genus needs to be recircumscribed.  相似文献   

10.
Several biochemical parameters, including that of polyamine content, accompanying the growth of the cyanobacterium Anacystis nidulans were studied. At all stages of growth under autotrophic conditions, the organisms were found to be rich in spermidine and lacking in spermine, as is typical of procaryotic organisms. The cells were quite low in putrescine, and no unusual polyamine was observed to be present as a major component. Conjugated polyamines were not detected in the cultures. At maximal culture density, the levels of spermidine, DNA, RNA, protein, and chlorophyll were also maximal. Shortly after the inception of the stationary phase, the spermidine content of the cells was the first parameter observed to decrease in cultures which were shortly to become yellow. Spermidine lost from the cells was not recovered in the medium in a free or conjugated form. This indication of degradation of spermidine was studied by the addition of polyamines to growing cultures. Exogenous spermidine and spermine were found to be metabolized rapidly by the organisms, of which diaminopropane was one product. Putrescine was found to be markedly toxic, whereas spermidine, some other triamines, and spermine were much less toxic.  相似文献   

11.
Skin-flap ischemia has been associated with the presence of free radicals. In this study, two enzyme systems involved in free-radical metabolism were used to compare a distal skin flap to a skin graft. Forty-two rats were divided into several test groups. A 10 X 3 cm dorsal rat flap was used, and tissue biopsies for xanthine oxidase and malonyldialdehyde (MDA) were obtained 2.5, 5.5, and 8.5 cm from the base of the flap at the hours given. In group I (control), the flap was outlined but not elevated, and biopsies were obtained. In group II, the flap was elevated, and biopsies were obtained at 6 hours. In group III, the flap was elevated, the distal 4 X 3 cm was amputated and replaced as a full-thickness skin graft, and biopsies were obtained at 6 hours. In group IV, the flap was elevated, and biopsies were obtained at 12 hours. In group V, the flap was treated as in group III, and biopsies were obtained at 12 hours. In group VI, the flap was elevated, and biopsies were obtained at 24 hours. In group VII, the flap was treated as in group III, and biopsies were obtained at 24 hours. Results: Xanthine oxidase was significantly higher in all distal biopsies compared to proximal biopsies. Xanthine oxidase also increased with time. Malonyldialdehyde increased over time as well as with distance from the flap base. Distal flap biopsies at 24 hours had greatly increased levels of malonyldialdehyde compared to skin grafts (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

12.
  用混合酸酐法(MA)将莱克多巴胺(RAC)偶联于牛血清白蛋白(BSA),合成人工抗原BSA-RAC,用UV和SDS-PAGE鉴定;用BSARAC免疫Balb/c小鼠,细胞融合技术建立高亲和力RAC单克隆抗体(mAb)杂交瘤细胞株,体内诱生腹水法制备RAC mAb;应用RAC mAb研制RAC残留快速检测ciELISA试剂盒(RAC-Kit),并测定其性能。结果表明,BSA-RAC偶联成功,分子结合比为24.5∶1;筛选出3株杂交瘤细胞,其中最好的4D8株亲和常数(Ka)为1.65×1010L/mol; RAC-Kit的检测限为0.5ng/ml,检测范围为0.5~151ng/ml,饲料样、猪尿样的平均添加回收率为87.2%,89.4%,平均批内和批间变异系数小于15%,与多巴酚丁胺的交叉反应率(CR%)为9.7%,与其它化合物无CR,RAC-Kit在4 ℃保存期为180d。  相似文献   

13.
The fermentation of fumarate and L-malate by Clostridium formicoaceticum was investigated. Growing and nongrowing cells degraded fumarate by dismutation to succinate, acetate, and CO2; on the other hand, only small amounts of succinate were detected when the organism was grown on L-malate. This dicarboxylic acid was mainly converted to acetate and CO2. The fermentation balances were modified if bicarbonate or formate were present in the medium. When C. formicoaceticum was grown in the presence of both dicarboxylic acids, fumarate was consumed before L-malate. The latter was mainly converted to acetate, whereas fumarate was fermented to acetate and succinate. Molar growth yields were determined to be 6 g of dry weight per mol of fumarate and 8 g of dry weight per mol of L-malate fermented.  相似文献   

14.
黑龙江省东部矿区鸟类群落多样性的比较分析   总被引:1,自引:0,他引:1  
2007年12月至2009年2月,采用样线法和样方法对黑龙江东部4个主要矿区(鸡西、鹤岗、双鸭山和七台河矿区)的鸟类群落多样性进行了调查,共记录到鸟类16目36科107种。其中古北种50种,东洋种11种,广布种46种;留鸟22种,夏候鸟64种,冬候鸟1种,旅鸟20种;国家Ⅰ级重点保护鸟类1种,国家Ⅱ级重点保护鸟类13种。4个矿区中以鸡西矿区的鸟类多样性和均匀性最高,鹤岗最低,这与煤矸石的堆积、采矿方式,以及矿区生境类型、植被演替等有关。在植被演替的不同阶段鸟类多样性存在差异,处于演替中期的针阔混交林中鸟类多样性最高,处于演替早期的阔叶林最低。  相似文献   

15.
The RNase (EC 2.7.7.16) in bovine milk was partially purified from milk whey. The basic properties and the hydrolyzing specificity of this enzyme were studied. This enzyme was heat stable. When RNA was used as the substrate, the pH optimum was 7.5 and 3′- nucleotides were produced, but the extent of the hydrolysis stopped at 31 per cent and core was left. C! and U! were hydrolyzed but purine cyclic nucleotides were not. Poly U was digested to 3′-uridylic acid passing through U! but poly A was not. These properties are quite similar to pancreatic RNase.  相似文献   

16.
The ability of virulent and avirulent strains ofVibrio vulnificus to overcome iron limitations by using iron bound to iron-binding proteins was examined. While no strains were able to obtain iron from lactoferrin or ferritin when these proteins were not fully saturated with iron, growth was enhanced by the iron-saturated form of these proteins. None of the strains was able to scavange iron from 30% saturated transferrin, but there were strain differences in the ability to obtain iron from the saturated form. The virulent strains were able to compete more efficiently with transferrin when it was fully saturated with iron than were the avirulent strains.  相似文献   

17.
目的研究肝硬化患者肠球菌感染的现状及药敏特点,以加强对肝硬化肠球菌感染的认识,指导用药。方法留取标本进行细菌培养、鉴定及药敏试验。结果所有纳入研究范围的肝硬化患者共检出肠球菌112株,其中粪肠球菌89株,占79.5%,比例最高,屎肠球菌占14.3%,居第2位。腹水中检出肠球菌64株,占57.1%,其次为痰和尿液,分别为38.1%和14.4%。肠球菌对红霉素、奈替米星的耐药率超过80%,对青霉素G、氨苄西林、呋喃妥因的敏感率超过70%,对左氧氟沙星的敏感率为58.9%,对头孢唑啉、头孢派酮的敏感率分别只有25.0%和33.0%,检出高耐氨基糖苷类肠球菌(HLAR)58株,占51.8%,未检出耐万古霉素和替考拉宁肠球菌,但检出万古霉素中介肠球菌4株,占3.6%。结论肠球菌是肝硬化患者医院感染的重要致病菌,尤以粪肠球菌和屎肠球菌为主,屎肠球菌的耐药率高于粪肠球菌,万古霉素和替考拉宁是治疗肠球菌感染的首选药物。  相似文献   

18.
单链抗体2F3表达条件的优化及其提纯和性质研究   总被引:4,自引:1,他引:3  
将构建好的单链抗体 2F3表达载体pTMF2F3ScFv转化到大肠杆菌BL21(DE3)。先挑选出表达量高的单克隆 ,然后让其在 37℃进行表达 ,并将表达时的培养条件进行优化。实验结果表明 :最佳诱导条件为开始诱导时的菌体密度OD590nm =1.0~ 1.8,所加异丙基β-D 硫代半乳糖苷 (IPTG)的浓度为 0.3~0.5mmol/L ,诱导时间 7h ,优化后目的蛋白表达量占菌体总蛋白的20% ,并用发酵罐成功地进行了扩大培养 ,筛选了洗涤包涵体的最佳条件。采用两步法对包涵体复性进行了研究 ,用Westernblotting及ELISA法检测了所表达的单链抗体及其生物活性 ,并成功制备了含硒单链抗体酶.  相似文献   

19.
The effects of stimulus size, eccentricity and colour on the amplitudes of N100 and N130 were investigated in pattern onset VEPs.For black-and-white pattern stimulation, the first set of stimuli was derived from a full dartboard pattern. Central stimulation of various extents was produced by patterns with reduced number of outer rings and for eccentric stimuli a number of central rings were removed from the full pattern. It was found that amplitude of N100 was maximal in VEPs to central stimuli and that it was greatly reduced when eccentric stimulation was applied. The amplitude of N130 showed no significant change in relation to the type of stimulus.When checkerboard stimuli of identical configuration were used for black-and-white pattern stimulation instead of dartboards, systematic changes in peak latencies of N100 were observed in relation to check size. In VEPs to centrally presented small checks the emergence of an early negative peak preceding N100 was recorded at 75 msec. In VEPs to coarse checkerboards presented centrally N100 was often observed with a delayed peak latency of 110 msec. Changes in N130 were not regular when checkerboards with different check sizes were presented centrally. For eccentric checkerboard stimulation, both negative peaks N100 and N130 were revealed. Their peak latencies were similar to those observed in the case of dartboard paracentral stimulation.In VEPs to patterns projected through red or blue filters, regular changes were observed in both negative peaks. Introduction of the red filter led to enhancement of the N100 amplitude in VEPs to dartboard and to checkerboards with fine checks, but it caused no effect on N100 in the VEPs to coarse checkerboards. Introduction of the blue filter led to a decrease in the N100 amplitude in VEPs to dartboard and fine checkerboards and to a slight increase of N100 VEPs to coarse checkerboards. Changes in N130 were observed only when the blue filter was introduced and they corresponded to those which take place when the level of illumination changes from photopic to mesopic.  相似文献   

20.
Conventional bacteriology techniques were used to identify enterococci isolates cultured from patients at different hospitals in Tehran during 2000-2001. The identification was confirmed using species-specific PCR targeting the D-alanyl-D-alanine ligase gene. A total of 59 isolates of Enterococcus faecalis were identified. The rates of resistance to different antibiotics were in the following order: penicillin 84%, ciprofloxacin 42%, high-level gentamicin 30%, nitrofurantoin 14%, imipenem 4%, and chloramphenicol 2%. Resistance to ampicillin was found to be rare among the Iranian isolates of E. faecalis. Multi-locus enzyme electrophoresis was then used to analyze the strains. Forty-five electrophoretic types were obtained when 10 enzyme loci were screened. Although the collection of bacterial isolates was limited in time and location, considerable heterogeneity was found. Analysis of strains for linkage disequilibrium demonstrated that the studied population is not clonal, since the index of association was not significantly different from zero (Ia = 0.0296). Enterococcus faecalis isolates recovered from patients in Tehran were genetically diverse and seemed to possess a high potential for genetic recombinations, though none were resistant to vancomycin.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号