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81.
江苏省GSP试点工作通过加强组织领导、广泛宣传推动、强化培训指导和注重检查交流等措施,基本建立了兽药GSP制度的框架,进一步提高和统一了对兽药GSP的认识,提高了试点企业的质量管理水平。但在兽药GSP实施过程中,存在对其重要性认识不足,部分暂行管理办法内容与实际脱节,技术指导力量薄弱等问题。  相似文献   
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Biological silages were prepared from shrimp head and octopus viscera by-products recuperated from the Tunisian seafood industry. Physical and biochemical changes and microbiological profiles were determined for raw materials during fermentation and on end-products. Results showed that biological silage significantly affected (p < 0.05) moisture, protein, and ash contents of shrimp head (CSHS) and octopus viscera silages (COVS). CSHS and COVS were stable, and their final pH values were 4.31 ± 0.01 and 3.71 ± 0.00, respectively. Proteolysis activity was confirmed by a significant increase (p < 0.05) of soluble nitrogen and low molecular weight of protein (<260 Da) found on the end-products for both silages. Lipid oxidation was delayed by addition of 150 ppm ethoxyquin to the raw material prior to fermentation. Biogenic amines detected in raw shrimp and octopus samples decreased significantly (p < 0.05) during the silage process. Histamine and tyramine, detected at high levels on octopus viscera, were absent in the end-products. Tyramine was produced in CSHS, indicating the possibility of the bacterial decarboxylation of tyrosine. Microbiological profiles showed that both silage products were free from pathogenic and spoilage bacteria. Therefore, biological silage can be used as a conservation procedure of shrimp and octopus by-products. The storage period could be shorter than 30 days, and further analysis should be carried out to ascertain safety and nutritional value of silage products.  相似文献   
84.
Discovery after discovery, host-associated microbiota reveal a growing list of positive effects on host homeostasis by contributing to host nutrition, improving hosts’ immune systems and protecting hosts against pathogens. In that context, a collection of oyster associated bacteria producing antibacterial compounds have been established to evaluate their role in non-host-derived immunity. Here, we described alterins; potent anti-Gram negative compounds produced by Pseudoalteromonas hCg-6 and hCg-42 isolated from different healthy oyster hemolymph. The strains hCg-6 and hCg-42 produce a set of at least seven antibacterial compounds, ranging from 926 to 982 Da structurally characterized as cyclolipopeptides (CLPs). Alterins share the same cationic heptapeptidic cycle connected via an amido bond to different hydrophobic hydrocarbon tails. Their MICs disclosed a potent antibacterial activity directed against Gram-negative bacteria including oyster and human pathogens that may confer a beneficial defense mechanism to the host but also represents an untapped source of new antibiotics. The alterins’ mechanisms of action have been deciphered: after binding to lipopolysaccharides (LPS), alterins provoke a membrane depolarization and permeabilization leading to bacterial lysis. As hCg-6 and hCg-42 produced a set of natural derivatives, the structure/activity relationship linked to the carbon tail is clarified. We showed that the hydrocarbon tail determines the LPS-binding properties of alterins and consequently their antibacterial activities. Its length and saturation seem to play a major role in this interaction.  相似文献   
85.
Recharge in Volcanic Systems: Evidence from Isotope Profiles of Phenocrysts   总被引:2,自引:0,他引:2  
Strontium isotope ratios measured from core to rim across plagioclase feldspar crystals can be used to monitor changes in the isotope composition of the magma from which they grew. In samples from three magma systems from convergent margin volcanoes, sudden changes in major element composition, petrographic features, and strontium isotope composition were found to correspond to discrete magmatic events, most likely repeated recharge of more mafic magma with lower ratios of strontium-87 to strontium-86 into a crustally contaminated magma.  相似文献   
86.
Many variables may affect the outcome of continuous infusion studies. The results largely depend on the experience of the laboratory performing these studies, the technical equipment used, the choice of blood vessels and hence the surgical technique as well the quality of pathological evaluation. The latter is of major interest due to the fact that the pathologist is not involved until necropsy in most cases, i.e. not dealing with the complicated surgical or in-life procedures of this study type. The technique of tissue sampling during necropsy and the histology processing procedures may influence the tissues presented for evaluation, hence the pathologist may be a source of misinterpretation. Therefore, ITO proposes a tissue sampling procedure and a standard nomenclature for pathological lesions for all sites and tissues in contact with the port-access and/or catheter system.  相似文献   
87.
Rift Valley fever (RVF) is a mosquito-borne viral zoonosis of increasing global importance. Occurring since 1930 across Africa, it was detected for the first time in Saudi Arabia and Yemen in September 2000, leading to human deaths and major losses in livestock populations. Assuming the virus has not survived in Yemen or has been circulating at a low level, authors qualitatively assessed the likelihood of “re-introduction” of RVF into Yemen through the legal importation of small ruminants from the Horn of Africa. The overall probability of introduction was assessed very low to medium, increasing during festival periods and higher when considering a direct transmission exposure as compared to a vectorial transmission exposure. The uncertainty was considered to be medium underlining important gaps in information that need to be fulfilled in the region. Options to reduce the risk are proposed and discussed, including possible improvements of the current Yemeni quarantine system.  相似文献   
88.
The aim of this work was to obtain a series of genetically related lines of Eragrostis curvula with different ploidy levels and reproductive modes, which can be used for the discovery of genes associated to diplospory. E. curvula is a widely cultivated forage grass native to Southern Africa that reproduces naturally by obligate diplosporous apomixis (asexual reproduction by seeds) of the Antennaria type. In vitro culture of immature inflorescences of the apomictic cultivar Tanganyika led to the regeneration of a diploid plant with a particular morphology (plant UNST1122). Embryo sac analysis and progeny tests determined that plant UNST1122 reproduces by sexuality. UNST1122 was cloned by dividing its tillers and a R 1 generation was obtained from seeds after open pollination among the diploid clones. A set of 500 seeds from a diploid R 1 plant was treated with colchicine and two plants showing a duplicated chromosome number (2n = 4x = 40) were obtained (plants UNST1112 and UNST1131). Progeny tests using RAPDs indicated that these plants reproduce also by sexuality. The availability of sexual tetraploid genotypes of E. curvula will allow the production of hybrids with new interesting combinations of agronomic traits and the developing of mapping populations segregating for diplospory. Besides, these genetically related plants with different reproduction modes constitutes an excellent model for the identification of gen(es) involved in diplosporous apomixis by mRNA profiling as well as to study the genomic rearrangements and gene expression alterations associated to changes at ploidy levels.  相似文献   
89.
The aim of this study was to investigate the influence of zinc (Zn) on the health of cumulus–oocyte complex (COC) during in vitro maturation (IVM). Experiments were designed to evaluate the effect of Zn added to IVM medium on: DNA integrity, apoptosis, cumulus expansion and superoxide dismutase (SOD) activity of cumulus cells (CC). Also, role of CC on Zn transport during IVM was evaluated on oocyte developmental capacity. DNA damage and early apoptosis were higher in CC matured with 0 μg/ml Zn compared with 0.7, 1.1 and 1.5 μg/ml Zn (p < 0.05). Cumulus expansion did not show differences in COC matured with or without Zn supplementation (p > 0.05). Superoxide dismutase activity was higher in COC matured with 1.5 μg/ml Zn than with 0 μg/ml Zn (p < 0.05). Cleavage and blastocyst rates were recorded after IVM in three maturation systems: intact COCs, denuded oocytes with cumulus cells monolayer (DO + CC) and denuded oocytes (DO). Cleavage rates were similar when COC, DO + CC or DO were matured with 1.5 μg/ml Zn compared with control group (p > 0.05). Blastocyst rates were significantly higher in COC than in DO + CC and DO with the addition of 1.5 μg/ml Zn during IVM (p < 0.01). Blastocyst quality was enhanced in COC and DO + CC compared with DO when Zn was added to IVM medium (p < 0.001). The results of this study indicate that Zn supplementation to IVM medium (i) decreased DNA damage and apoptosis in CC; (ii) increased SOD activity in CC; (iii) did not modify cumulus expansion and cleavage rates after in vitro fertilization; (iv) improved subsequent embryo development up to blastocyst stage; and (v) enhanced blastocyst quality when CC were present either in intact COC or in coculture during IVM.  相似文献   
90.
This study was designed to evaluate the epidemiology of severe gastroenteritis in children living in Québec rural areas with intensive livestock activities. From September 2005 through June 2007, 165 cases of gastroenteritis in children aged from 6 months to 5 years, hospitalized or notified to the public health department were enrolled, and 326 eligible controls participated. The parents of cases and controls were asked questions about different gastroenteritis risk factors. The quality of the drinking water used by the participants was investigated for microbial indicators as well as for four zoonotic bacterial pathogens (Campylobacter spp, Escherichia coli, Salmonella spp and Yersinia spp) and two enteric parasites (Cryptosporidium spp and Giardia spp). From 134 stool specimen analysed, viruses were detected in 82 cases (61%), while 28 (21%) were found with at least one of the bacteria investigated, and five cases were infected by parasites. Campylobacteriosis was the main bacterial infection (n = 15), followed by Salmonella sp (n = 7) and E. coli O157:H7 (n = 5) among cases with bacterial gastroenteritis. No significant difference was found between cases and controls regarding the quality of water consumed; the frequency of faecal contamination of private wells was also similar between cases and controls. Considering the total cases (including those with a virus), no link was found between severe gastroenteritis and either being in contact with animals or living in a municipality with the highest animal density (4th quartile). However, when considering only cases with a bacterial or parasite infection (n = 32), there was a weak association with pig density that was not statistically significant after adjusting for potential confounders. Contact with domestic, zoo or farm animals were the only environmental factor associated with the disease.  相似文献   
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