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91.
A series of 11 N-(p-sulfonylphenyl)-N1-carbamoylureas was prepared by reaction of 1,6-diphenyl-2,4-dioxohexahydro-s-triazine with chlorosulfonic acid and thionyl chloride. The resultant N-(p-chlorosulfonylphenyl)-N1-carbamoylurea was subsequently condensed with amines, butanol, hydrazine and sodium azide. The hydrazide was reacted with carbonyl compounds and the azide with trimethyl phosphite. The products were tested for in-vivo fungicidal activity against barley powdery mildew (Erysiphe graminis); the acetone hydrazone derivative showed the highest activity. © 1998 SCI.  相似文献   
92.
OBJECTIVE: To determine whether a homologue of A-kinase anchor protein 4 (AKAP4) is present and functional as an AKAP in equine spermatozoa and examine the effect of semen cooling and cryopreservation on binding of equine AKAP4 to the regulatory (RII) subunit of protein kinase-A (PK-A). SAMPLE POPULATION: Ejaculated semen collected from 2 fertile stallions, 3 bulls, and 3 humans. PROCEDURE: Identification of an equine homologue of AKAP4 was investigated via DNA sequencing. Protein was extracted from the spermatozoa of each species for immunoblot analysis to identify AKAP4 and its precursor protein, pro-AKAP4; immunofluorescence microscopy was used to localize those proteins in spermatozoa. Ligand overlay assays were used to determine whether the identified proteins bound to the RII subunit of PK-A and whether cooling or cryopreservation of spermatozoa affected that binding. RESULTS: The partial genomic sequence of AKAP4 was identified in equine spermatozoa, and immunoblot analysis confirmed that AKAP4 and pro-AKAP4 are present in equine spermatozoa. Via immunofluorescence microscopy, these proteins were localized to the spermatozoal principal piece. Results of ligand overlay assays indicated that equine AKAP4 and pro-AKAP4 bind to the RII subunit of PK-A and are AKAPs; AKAP4-RII binding was not affected by cooling or cryopreservation of spermatozoa. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that equine AKAP4 anchors PK-A to the spermatozoal flagellum (where the kinase is likely to be required for the regulation of spermatozoal motility), but decreases in spermatozoal motility in cooled or cryopreserved semen are not associated with decreased binding of AKAP4 and PK-A.  相似文献   
93.
Foot-and-mouth disease (FMD) is one of the most devastating animal diseases, affecting all cloven-hoofed domestic and wild animal species. Previous studies from our group using DNA vaccines encoding FMD virus (FMDV) B and T cell epitopes targeted to antigen presenting cells, allowed demonstrating total protection from FMDV homologous challenge in those animals efficiently primed for both humoral and cellular specific responses (Borrego et al. Antivir Res 92:359-363, 2011). In this study, a new DNA vaccine prototype expected to induce stronger and cross-reactive immune responses against FMDV which was designed by making two main modifications: i) adding a new B-cell epitope from the O-serotype to the B and T-cell epitopes from the C-serotype and ii) using a dual promoter plasmid that allowed inserting a new cistron encoding the anti-apoptotic Bcl-xL gene under the control of the internal ribosomal entry site (IRES) of encephalomyocarditis virus aiming to increase and optimize the antigen presentation of the encoded FMDV epitopes after in vivo immunization. In vitro studies showed that Bcl-xL significantly prolonged the survival of DNA transfected cells (p?<?0.001). Accordingly, vaccination of Swiss out-bred mice with the dual promoter plasmid increased the total IgG responses induced against each of the FMDV epitopes however no significant differences observed between groups. The humoral immune response was polarized through IgG2a in all vaccination groups (p?<?0.05); except peptide T3A; in correspondence with the Th1-like response observed, a clear bias towards the induction of specific IFN-γ secreting CD4+ and CD8+ T cell responses was also observed, being significantly higher (p?<?0.05) in the group of mice immunized with the plasmid co-expressing Bcl-xL and the FMDV B and T cell epitopes.  相似文献   
94.
Mass vaccination with reduced dose 1/50 Rev 1 strain live vaccine (1–2 109 colony forming units), administered subcutaneously, over a four and a half year period reduced the prevalence of Brucella melitensis in Kuwait's small ruminant population from 5.8% in 1993 to 2.02% in 1997.Serological test results using the Rose Bengal Plate Test, Rivanol Agglutination Test and Complement Fixation showed no evidence of persistence of positive serology in animals nine or more months after vaccination. Questionnaires and post-vaccination flock inspections found that the effects on gestation (abortions) were minimal – and not proven to be due to the vaccine.The conclusion from these findings is that mass vaccination with reduced dose Rev 1 administered by the subcutaneous route is a practical field strategy for control of Brucella melitensis.  相似文献   
95.
Genetic Resources and Crop Evolution - The Saccharum species members are extremely complex allopolyploids. In this study, sixty Saccharum spp. hybrids were analyzed using simple sequence repeat...  相似文献   
96.
Abstract

In this paper, an integrated management system for the planning and activation of a field monitoring task is presented. The architecture of the system is built around a mobile robotic unit. The internet-based architecture of the system includes a station unit that works as a mobile on-farm operating console, the mobile robotic unit and a field server for generating and storing maps. The hypothesis is that it is possible to automate the planning and execution of the operation of monitoring the in-field weed density and species distribution. The developed planning system includes the automatic field geometrical representation and the route planning for the mobile unit. For the field representation two algorithmic approaches for automated track generation were used. For the route planning, a graph-based field coverage algorithm and a discrete grid-based path planning method were used. The low computational requirements of the implemented algorithms make it feasible to adopt a real-time re-planning strategy in which a set of new planning problems are solved based on the latest information. The central part of such a planning, concerns the dynamic re-evaluation of the initial plan for sampling and routing based on the on-line analysis of the samples. This provides the basis for a fully sequential adaptive adjustment of the sampling procedure after each individual sampling. It is expected that such a dynamic targeted sampling and routing system will reduce the overall cost and time consumption of the weed monitoring operation.  相似文献   
97.
The objective of this study was to determine the effects of soybean meal (SBM) or spray-dried blood meal (BM) supplementation of diets based on untreated (UNT-WS) or alkaline hydrogen peroxide-treated wheat straw (AHP-WS). A 4 x 4 Latin square design with a 2 x 2 factorial arrangement of treatments was used. Variables included nutrient digestion and flow to the duodenum. Four Simmental steers (average weight 477 kg) fitted with ruminal and duodenal cannulas were fed 65% UNT-WS or AHP-WS based diets in 12 equal portions daily. Diets were formulated to contain 10% CP. Chromic oxide was used as the digesta flow marker and purines were used as the microbial marker. There were no straw type x protein source interactions. Total tract and ruminal OM digestibility were approximately 25% greater (P < .04) when AHP-WS was fed than when UNT-WS was fed. Source of protein did not affect (P > .10) OM or fiber digestion in the rumen or total tract. Ruminal digestion of NDF and ADF was increased (P < .01) by 51 and 40%, respectively, when AHP-WS was fed than when UNT-WS was fed. Main effect means (P > .10) for N flow to the duodenum as a percentage of N intake were 128.2, 142.5, 133.4, and 137.6 for UNT-WS, AHP-WS, SBM, and BM treatments, respectively. Despite increased (P < .01) ruminal OM digestion for AHP-WS, microbial N flow to the duodenum was greater (P < .01) when UNT-WS was fed than when APH-WS was fed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
98.
SDS-PAGE电泳在鉴别用牛乳掺伪的新疆特种乳中的应用   总被引:1,自引:0,他引:1  
[目的]采用十二烷基磺酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)鉴别一定比例掺伪的特种乳中所含的牛乳成分及确定最低检测掺伪比例。[方法]按一定的比例(1∶1、1∶4、1∶10、1∶20、1∶100、1∶200和1∶400(V牛乳/V特种乳))掺伪,离心分离乳清蛋白,SDS-PAGE电泳,确定掺伪差异性蛋白并进行灰度分析。[结果]SDS-PAGE可以快速、有效地分离各乳乳清蛋白以及掺伪的牛乳乳清蛋白。[结论]SDS-PAGE鉴别掺伪的最低比例为1∶10(V_(牛乳_/V_(特种乳))。  相似文献   
99.
This experiment investigated the effect of a supplementary dietary source (flaxseed) on egg yolk cholesterol contents and fatty acid profile. Flaxseeds at three different levels (5, 10, and 15%) were supplemented to 84 Rhode Island Red × Fayoumi cross layers during 21–24 weeks of age. The birds were divided randomly into four groups. Flaxseeds were supplemented in the diet at the level of 5% (FS‐5), 10% (FS‐10), and 15% (FS‐15), and one group served as the control (FS‐0). Cholesterol content of eggs was not significantly affected by flaxseed. The amount of monounsaturated fatty acids was significantly decreased with the increase in the flaxseed level, and the highest reduction was observed in FS‐15. The highest total polyunsaturated fatty acid (PUFA) and total omega‐3 PUFA were recorded in FS‐15. These findings reflect that unsaturated healthy fatty acid content in poultry eggs can be increased with dietary supplementation of flaxseed.  相似文献   
100.
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