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1.
The purpose of this study was to characterize, at the molecular level, the Ehrlichia canis strains involved in naturally occurring canine monocytic ehrlichiosis (CME) in Greece, and to investigate if any sequence diversity exists between the 16S rRNA genes of those involved in the mild non-myelosuppressive or the severe myelosuppressive form of CME. To this end, amplification of the ehrlichial 16S rRNA gene was attempted by nested polymerase chain reaction (PCR) assays in bone marrow (BM) aspirates from 20 dogs tentatively diagnosed as having non-myelosuppressive (n=10, group A) or myelosuppressive (n=10, group B) CME. PCR assay using E. canis-specific primers revealed that 15 BM samples, including all group A and 5 group B dogs, were positive. Using universal PCR primers, a nearly full-length 16S rRNA gene could be amplified from 13 BM samples, including 9 group A and 4 group B dogs. The 16S rDNA analysis based on secondary structure revealed that all sequences of the Greek strains were identical to each other and indicated 100% identity among some American (Venezuelan and Brazilian), European (Greek), Middle Eastern (Turkish) and Asiatic (Thailand) strains. The results of this study suggest that the E. canis strains involved in the non-myelosuppressive and myelosuppressive forms of CME in Greece share an identical 16S rRNA genotype.  相似文献   
2.
The objective of this study was to assess the effects of in‐feed chlortetracycline (CTC) as a measure of preventing or minimizing infectious problems of reproductive failure in gilts and sows. In a farm of 400 Large White × Landrace gilts and sows with a clinical history of porcine respiratory and reproductive syndrome (PRRS) virus, the animals were treated with CTC. Treatment consisted of 10 g CTC sow/day for 15 days every 3 months. It improved the health status of sows by decreasing post‐farrowing clinical mastitis and vaginal discharges, abortions, return‐to‐oestrus and irregular return‐to‐oestrus rates. These beneficial effects had a positive impact on the performance of the litter. More piglets were born live and weaned. These positive effects improved with repeated use of CTC. The serological evidence of PRRS virus, Leptospira spp. and Chlamydia spp. and the subsequent beneficial use of the antimicrobial agent indicate that reproductive failure, possibly resulting from the bacterial agents can be controlled with in‐feed use of broad spectrum antimicrobials.  相似文献   
3.
The aim of this study was to estimate the relative diagnostic sensitivity and specificity of a polymerase chain reaction (PCR) assay in the serum of dogs with naturally occurring non-myelosuppressive canine monocytic ehrlichiosis (CME), and to investigate the association between PCR positivity and immunofluorescence antibody (IFA) titres for Ehrlichia canis. Serum samples obtained from 38 dogs with non-myelosuppressive CME and 12 healthy dogs were analyzed retrospectively. Each serum sample was analyzed in triplicate using an E. canis-specific nested PCR assay targeting a 389 bp sequence of the 16S rRNA gene. E. canis DNA was amplified in 24 of 38 (63.1%) affected dogs; all samples from healthy dogs were negative. A high level of agreement was found among the PCR replicates (P < 0.0001). Median IFA titre of the 24 PCR-positive dogs was significantly lower than that of the PCR-negative infected dogs (P = 0.0029), indicating that E. canis DNA may circulate prior to the development of a high antibody titre. Serum-based PCR analysis is suggested for the early diagnosis of CME when whole blood samples are not available.  相似文献   
4.
Recent advances in optical designs and electronic circuits have allowed the transition from passive to active proximal sensors. Instead of relying on the reflectance of natural sunlight, the active sensors measure the reflectance of modulated light from the crop and so they can operate under all lighting conditions. This study compared the potential of active and passive canopy sensors for predicting biomass production in 25–32 randomly selected positions of a Merlot vineyard. Both sensors provided estimates of the normalized difference vegetation index (NDVI) from a nadir view of the canopy at veraison that were good predictors of pruning weight. Although the red NDVI of the passive sensors explained more of the variation in biomass (R 2 = 0.82), its relationship to pruning weight was nonlinear and was best described by a quadratic regression (NDVI = 0.55 + 0.50 wt−0.21 wt2). The theoretically greater linearity of the amber NDVI-biomass relationship could not be verified under conditions of high biomass. The linear correlation to stable isotope content in leaves (13C and 15N) provided evidence that canopy reflectance detected plant stresses as a result of water shortage and limited fertilizer N uptake. Thus, the canopy reflectance data provided by these mobile sensors can be used to improve site-specific management practices of vineyards.  相似文献   
5.
Field and greenhouse pot experiments were conducted to evaluate the potential to use intercropping as an alternative method to increase glucosinolates in Brassicas by manipulating nitrogen (N) and sulfur (S) balance by intercropping with lettuce (Lactuca sativa L. var. capitata). In both experiments, four combinations of N and S fertilization were used. In the field experiment no effect of intercropping on the total glucosinolate concentration was found as the growing lettuce was strongly inhibited by the presence of broccoli (Brassica oleracea L. var. italic). In contrast to this, in the pot experiment both total and individual glucosinolate concentrations in red leaf mustard (Brassica juncea L.) increased by intercropping. Fertilization treatments influenced glucosinolate concentrations in both experiments, and an interaction between N and S fertilization was noticed.  相似文献   
6.
In this work, the adhesive systems used today in the European industries of particleboard, medium density fibreboard (MDF) and oriented strand board (OSB) are discussed. The structure of particleboard, MDF and OSB markets in Europe in relation to the types of adhesives and product specifications are presented as well. It is noticeable that new markets for wood-based panels like particleboard and fibreboard, known as non-furniture markets, are growing in Europe at a fast rate. It was concluded that most of the technological changes concerning the adhesive systems applied and additives have been realised from the need for niche panel products, the obligation to reach even lower formaldehyde emissions, and the necessity to decrease production costs due to the stringent competition in the market of wood-based panels.  相似文献   
7.
Clostridium perfringens isolated from lambs with dysentery (n=117) were analysed by a DNA amplification technique, the polymerase chain reaction (PCR), in order to determine the prevalence of the alpha-, beta-, beta 2-, epsilon-, iota- and enterotoxin genes. The most prevalent toxin type of C. perfringens found was type B, containing the alpha-, beta-, and epsilon-toxin genes, representing 46% of the cases with clostridial dysentery. C. perfringens type C containing the alpha-, and beta-toxin genes was isolated in 20% and type D, which is characterized by the alpha- and epsilon-toxin genes, was isolated in 28% of all isolates. The recently discovered, not yet assigned beta 2-toxigenic type of C. perfringens was represented in 6% of all isolates. No C. perfringens type A containing the alpha-toxin alone and no type E, which harbours the ADP-ribosylating iota-toxin, were found in the diseased animals. None of the samples contained the enterotoxin gene. Only one type of C. perfringens was found in a given herd, revealing the epidemiological use of PCR toxin gene typing of C. perfringens. The animals originated from 79 different herds with sizes ranging from 30 to 250 animals, bred in the area of northern Greece.  相似文献   
8.
The molecular mechanisms involved in the development of type 2 diabetes are poorly understood. Starting from genome-wide genotype data for 1924 diabetic cases and 2938 population controls generated by the Wellcome Trust Case Control Consortium, we set out to detect replicated diabetes association signals through analysis of 3757 additional cases and 5346 controls and by integration of our findings with equivalent data from other international consortia. We detected diabetes susceptibility loci in and around the genes CDKAL1, CDKN2A/CDKN2B, and IGF2BP2 and confirmed the recently described associations at HHEX/IDE and SLC30A8. Our findings provide insight into the genetic architecture of type 2 diabetes, emphasizing the contribution of multiple variants of modest effect. The regions identified underscore the importance of pathways influencing pancreatic beta cell development and function in the etiology of type 2 diabetes.  相似文献   
9.
Obesity is a serious international health problem that increases the risk of several common diseases. The genetic factors predisposing to obesity are poorly understood. A genome-wide search for type 2 diabetes-susceptibility genes identified a common variant in the FTO (fat mass and obesity associated) gene that predisposes to diabetes through an effect on body mass index (BMI). An additive association of the variant with BMI was replicated in 13 cohorts with 38,759 participants. The 16% of adults who are homozygous for the risk allele weighed about 3 kilograms more and had 1.67-fold increased odds of obesity when compared with those not inheriting a risk allele. This association was observed from age 7 years upward and reflects a specific increase in fat mass.  相似文献   
10.
This study provides a contribution to hard-type cheese starter culture production through the use of a freeze-dried culture in the ripening of hard-type cheeses. The effect of initial cell concentration, ripening temperature, and cell immobilization of kefir on the degree of openness, mold spoilage, microbial associations, physicochemical characteristics, and aroma-related compounds was studied. Use of kefir starter cultures resulted in cheese with an increased shelf life and resistance to spoilage as compared to control cheeses without kefir inoculants. Furthermore, the freeze-dried kefir culture improved aroma, taste, and texture characteristics while increasing the degree of openness in comparison to traditional hard-type cheese products. The kefir culture resulted in an increase in counts of total aerobic bacteria, yeasts and molds, lactococci, and lactobacilli until the 15th day of ripening. From then on, only lactobacilli counts increased, reaching levels up to 9.17 log CFU/g in cheeses ripened at 5 degrees C using freeze-dried kefir cells immobilized on casein. SPME-GC/MS analysis revealed major differences in volatile composition, especially with regard to alcohols (up to 75%), carbonyl compounds (up to 75%), and esters (up to 64%) between cheeses made with kefir cells and cheeses made without kefir inoculants.  相似文献   
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