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111.
A qualitative and semi-quantitative polymerase chain reaction(PCR)-based assay was developed for the detection of severalpotentially Harmful Algal Bloom (HAB) species and genera belongingto Dinophyceae, Bacillariophyceae and Raphydophyceae. Oligonucleotideprimers were designed based on Internal Transcribed Spacer (ITS)–5.8Sribosomal DNA (rDNA) sequences available in public databaseor identified in this study. The specificity and sensitivityof the PCR assay were validated using clonal cultures and thennatural seawater samples, as well as the known copy number ofplasmids containing the target ITS–5.8S rDNA regions.A filter system for collecting mixed phytoplankton cells coupledto a target species-specific PCR assay was performed on spatialand temporal series of net and surface seawater samples duringcoastal water monitoring carried out in several localities ofthe Mediterranean Sea. The application of PCR allowed a rapiddetection of various genera and species-specific potential HABtaxa in all examined natural samples. Qualitative and semi-quantitativePCR results obtained from field samples were compared with microscopic[light microscope (LM)] examinations. The two methods gave comparableresults, and the molecular assay was able to detect HAB targetcells at concentrations not detectable by microscopy or thoseof uncertain identity. The highest values of positive detectionof potential HAB taxon presence obtained by PCR assay comparedwith the microscopic examination ranged from 67 to 8.0%.  相似文献   
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Fourteen native strains of Trichoderma spp. from wildand agricultural pathosystems in the state of Yucatan, Mexico, with growth-promoting ability of Capsicum chinense Jacq. seedlings were evaluated and antagonistic effect of their filtrate against second-stage juveniles (J2) of Meloidogyne incognita. The strains Th05-02 and Th27-08 showed the best significant effects on plant hight variable increments 55.57 and 47.62%, theTh07-04 with 29.48% more root length, theTh02-01 and Th07-04 isolates increased from 48.71 to 84.61% in volume radical and 53.40% of total dry biomass. Statistical analysis (p≤0.001) of Th43 and Th43-13-14 filtrates caused 100% mortality at 24 and 48h. In the test of reversibility to 24 h after replacing the filtrates Th43-13, Th43-14, TH09-06 and TH20-07 by sterile distilled water, the J2 did not recover their viability, so they were considered as the best potential strains of Trichoderma spp. with antagonistic capacity in J2 of M.incognita.  相似文献   
114.
Orally bioavailable inhibitors of β-(1,3)-d-glucan synthase have been pursued as new, broad-spectrum fungicidal therapies suitable for treatment in immunocompromised patients. Toward this end, a collaborative medicinal chemistry program was established based on semisynthetic derivatization of the triterpenoid glycoside natural product enfumafungin in order to optimize in vivo antifungal activity and oral absorption properties. In the course of these studies, it was hypothesized that the pharmacokinetic properties of the semisynthetic enfumafungin analog 3 could be improved by tethering the alkyl groups proximal to the basic nitrogen of the C3-aminoether side chain into an azacyclic system, so as to preclude oxidative N-demethylation. The results of this research effort are disclosed herein.  相似文献   
115.
目的:建立丙型肝炎病毒NS3/4A丝氨酸蛋白酶体内活性评价模型。方法:利用NS4A/B是NS3/4A丝氨酸蛋白酶作用底物的特性,构建融合基因NS3/NS4A/B-SEAP,底物片段NS4A/B插在NS3/4A和人分泌性碱性磷酸酶(SEAP)之间,融合基因表达后SEAP的分泌依赖于有活性的NS3/4A在NS4A/B位点的切割。将含融合基因的质粒NS3/4A(△4AB)SEAP通过水动力转染技术转染到小鼠体内,检测小鼠血清中SEAP的活性,高活性的SEAP是该评价体系成立的证据。结果与结论:在瞬时表达NS3/4A的小鼠血清中检测到了高活性的SEAP,建立了可用于评价抗NS3/4A的小鼠体内瞬时模型。  相似文献   
116.
Many organisms show well‐defined latitudinal clines in morphology, which appear to be caused by spatially varying natural selection, resulting in different optimal phenotypes in each location. Such spatial variability raises an interesting question, with different prospects for the action of sexual selection on characters that have a dual purpose, such as locomotion and sexual attraction. The outermost tail feathers of barn swallows (Hirundo rustica) represent one such character, and their evolution has been a classic model subject to intense debate. In the present study, we examined individuals from four European populations to analyze geographical variation in the length and mass of tail feathers in relation to body size and wing size. Tail feather length differed between sexes and populations, and such variation was a result of the effects of natural selection, acting through differences in body size and wing size, as well as the effects of sexual selection that favours longer tails. The extra enlargement of the tail promoted by sexual selection (i.e. beyond the natural selection optimum) could be achieved by increasing investment in ornaments, and by modifying feather structure to produce longer feathers of lower density. These two separate processes accounting for the production of longer and more costly tail feathers and less dense feathers, respectively, are consistent with the hypothesis that both Zahavian and Fisherian mechanisms may be involved in the evolution of the long tails of male barn swallows. We hypothesize that the strength of sexual selection increases with latitude because of the need for rapid mating as a result of the short duration of the breeding season at high latitudes. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105 , 925–936.  相似文献   
117.
ABSTRACT. Entodiniomorphid ciliates are often present in the colons of wild apes. In captive apes the infection tends to gradually disappear, with the exception of Troglodytella abrassarti . We used fecal examinations to screen the gorillas ( Gorilla gorilla gorilla ) in European (Czech Republic, UK) and Australian Zoos to explore the ape-to-ape transmission pattern of T. abrassarti . Gorillas from two out of three European Zoos were positive for T. abrassarti , while gorillas from the Australian Zoo were negative. We documented a horizontal transmission of T. abrassarti to a non-infected adult gorilla introduced into a Troglodytella -positive group in the Prague Zoo and traced the origin of the ciliate infection to the Paignton Zoo (UK) using serial fecal examinations. During this study, two infant gorillas born in the Prague Zoo (CZ) first became positive for T. abrassarti at the age of 9 mo. Ciliate morphology and the sequencing of the small subunit rRNA gene and the internal transcribed spacer rDNA spacer region revealed that T. abrassarti affects both captive gorillas and chimpanzees. We conclude that zoo transport plays a major role in the distribution of T. abrassarti among captive gorillas.  相似文献   
118.

Background  

Silica particles cationized by dioctadecyldimethylammonium bromide (DODAB) bilayer were previously described. This work shows the efficiency of these particulates for antigen adsorption and presentation to the immune system and proves the concept that silica-based cationic bilayers exhibit better performance than alum regarding colloid stability and cellular immune responses for vaccine design.  相似文献   
119.
The ideal free distribution (IFD) model predicts that a density‐dependent mechanism operates to regulate habitat selection and reproductive performance. We studied a Little Grebe Tachybaptus ruficollis population, which breeds on irrigation ponds in the Vega Baja Valley (southeastern Spain) to test the premises of the IFD model. These ponds are highly dynamic because they are managed according to agricultural requirements, and are subject to different levels of disturbance, which can change the quality of individual ponds across the landscape. Surveys were carried out during the breeding season from 2002 to 2006, with reproduction performance estimated during two consecutive breeding seasons, 2003 and 2004. Occupation frequency differed from random, indicating preference for some ponds over others. Habitat features such as pond construction and design, the presence of submerged vegetation, vegetation along the shore and reed beds, and pond area correlated with occupation frequency and might be considered to be indicators of pond quality. Ponds were occupied sequentially from best to worst. Thus, when the population size increased, the number of low‐quality ponds occupied also increased. High‐quality ponds held more breeding pairs than low‐quality ones, resulting in the mean reproductive success per breeding pair being independent of pond quality. Little Grebes therefore occupy ponds in a manner consistent with the expectations of the IFD model.  相似文献   
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