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11.
从肿头综合征鸡分离出产Vero毒素E.coli 总被引：1，自引：1，他引：0
本研究从哈尔滨郊区某鸡场肿头综合征（ Ｓ Ｈ Ｓ）鸡分离出 ３ 株血清型为 Ｏ７８ 的埃希氏大肠杆菌（ Ｅ．ｃｏｌｉ）,从鞍山 Ｓ Ｈ Ｓ病料分离出 １ 株血清型为 Ｏ８ 的 Ｅ．ｃｏｌｉ。并证实这 ４ 株 Ｅ．ｃｏｌｉ 能够对 Ｖｅｒｏ 细胞产生毒性作用,与产 Ｖｅｒｏ 毒素的 Ｅ．ｃｏｌｉ一致。对哈尔滨市郊 Ｓ Ｈ Ｓ病鸡做病理组织学观察,主要变化为头部皮下组织,头盖骨气室及鼻粘膜下纤维素性化脓性炎症,水肿和大肠杆菌性肉芽肿,心、肝、肾等器官炎症变化并有大量异嗜性粒细胞和细菌团块。 相似文献
12.
Winter wheat genotypes under different levels of nitrogen and water stress: Changes in grain protein composition 总被引：2，自引：0，他引：2
C. Saint Pierre C.J. Peterson A.S. Ross J.B. Ohm M.C. Verhoeven M. Larson B. Hoefer 《Journal of Cereal Science》2008,47(3):407-416
Hard white winter wheat with superior and consistent quality is preferable for Asian markets. This study investigated the combined influences of moisture deficit during grain-fill and N management on protein quality, dough rheological properties, and protein molecular weight distributions in soft and hard winter wheats. Genotypes were grown under an irrigation gradient and two N-fertilization levels. Grain polyphenol oxidase (PPO) activity, SDS sedimentation, and Mixograph analyses were evaluated. Flour protein composition was characterized using SE-HPLC. Moisture stress during grain-fill increased flour protein content. N fertilization increased flour protein content. No significant correlation was found between flour protein and PPO. Changes in protein composition were related to general increases in protein content, regardless if the result of reduced irrigation or increased fertilization rate. The percentage of monomeric proteins increased more than the polymeric proteins as flour protein increased. Similarly, SDS sedimentation volume increased as a function of protein content. As expected, subunit GluD1 5+10 was associated with larger sedimentation volume and higher dough strength in genotypes as compared to those with subunit GluD1 2+12. Biplot analyses showed that genotypes of similar protein quality and composition responded similarly to N and irrigation treatments. 相似文献
13.
Juliano Lauser Coletto Marcelo Peres Pinho Lauro Saint Pastous Madureira 《Fisheries Oceanography》2019,28(1):82-93
Skipjack tuna (Katsuwonus pelamis) ranks third among marine resources that sustain global fisheries. This study delimits the spatiotemporal habitat of the species in the south‐western Atlantic Ocean, based on operational oceanography. We used generalized additive models (GAMs) and catch data from six pole‐and‐line fishing vessels operating during 2014 and 2015 fishing seasons to assess the effect of environmental variables on catch. We also analysed Modis sensor images of sea surface temperature (SST) and surface chlorophyll‐α concentration (SCC) to describe fishing ground characteristics in time and space. Catch was positively related to thermocline depth (24–45 m), SST (22–24.5°C), SCC (0.08–0.14 mg/m³) and salinity (34.9–35.8). Through SST images, we identified that thermal fronts were the main surface feature associated with a higher probability to find skipjack. Also, we state that skipjack fishery is tightly related to shelf break because bottom topography drives the position of fronts in this area. Ocean colour fronts and plankton enrichment were important proxies, accessible through SCC, used to delineate skipjack fishing grounds. Catch per unit effort (CPUE) was higher towards summer (median 14 t/fishing day) due to the oceanographic characteristics of the southern region. High productivity in this sector of the Brazilian coast defines the main skipjack feeding areas and, as a consequence, the greatest abundance and availability for fishing. 相似文献
14.
M Saint‐Dizier A‐C Legendre M‐A Driancourt S Chastant‐Maillard 《Reproduction in domestic animals》2014,49(6):920-925
Luteolysis before the time of maternal recognition of pregnancy is one cause of low fertility in high‐producing dairy cows. The objective of this study was to assess whether induction of a secondary corpus luteum (CL) late in the luteal phase would delay the time of luteolysis. Twenty high‐producing Holstein cows were synchronized to ovulation (Day 0) with the Ovsynch protocol and received hCG (1500 IU im) on Day 12. Corpora lutea formation (as evaluated by ultrasonography) and plasma P4 concentrations were monitored from Days 4 to 36. hCG treatment induced the formation of one secondary CL (CL2) in 11 of 20 cows (55%) from the dominant follicle (mean diameter: 14.2 ± 0.9 mm) of two‐wave (3/11) and three‐wave (8/11) cycles. The maximal diameter of the CL2 (23.3 ± 1.9 mm) was reached approximately 6 days after hCG treatment and was correlated with its structural lifespan (p < 0.01). Cows that formed a CL2 after hCG had higher mean plasma P4 concentrations on Day 14 (+4.5 ng/ml) and Day 18 (+3.0 ng/ml) compared with cows without CL2 (p < 0.05). The structural regression of CL2 begun approximately 8 days after that of the CL1, and the median time at which the first drop in circulating P4 levels occurred was later in cows that formed a CL2 than in those that did not (Day 26 vs Day 18; p < 0.01). Thus, the induction of a CL2 by hCG on Day 12 might reduce the risk of premature luteolysis in high‐producing dairy cows after insemination. 相似文献
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16.
Lezmi S Thibault-Duprey K Bidaut A Hardy P Pino M Macary GS Barbellion S Brunel P Dorchies O Clifford C Leconte I 《Veterinary pathology》2011,48(5):964-969
Recently, 6% of 1,176 Sprague Dawley rats examined in our reproductive toxicity studies presented with dark-red uterine contents with or without fetuses demonstrating delayed development. Sometimes, a high proportion of the litter was found dead, and dystocia with death or preterminal euthanasia of the dam occurred. Microscopic findings in the uterus consisted of necrohemorrhagic and suppurative periplacentitis associated with the presence of bacterial colonies identified as Escherichia coli. In the vagina, similar findings were observed that were associated with mucus accumulation and the presence of a transverse occlusive or partially occlusive thin membrane identified as a vaginal septum. Microscopically, this septum consisted of a thin band of connective tissue covered on both sides by a mucous epithelium that was continuous with vaginal epithelium. In some cases, there was only mucus accumulation retained by a septum in the vagina without evidence of bacterial infection. Serological and histological examinations did not reveal any specific pathogenic agent. The presence of these septa in the vagina most likely favored mucus accumulation, nonspecific ascending bacterial infection, and dystocia. This colony of rats presented with an unusually high incidence of vaginal septa as it was described in different strains of mice and rats in the past. We hypothesized that the use of an impedance meter by the breeder--to determine the phase of the estrous cycle by introducing a probe in the vagina--likely facilitated gestation by perforating the vaginal septum in some cases. 相似文献
17.
Ferrand C Marc F Fritsch P Cassand P de Saint Blanquat G 《Journal of agricultural and food chemistry》2000,48(8):3605-3610
Sorbic acid (E200) and its salts (potassium and calcium sorbate: E202 and E203) are allowed for use as preservatives in numerous processed foods. Sorbic acid has a conjugated system of double bonds which makes it susceptible to nucleophilic attack, sometimes giving mutagenic products. Under conditions typical of food processing (50-80 degrees C), we analyzed the cyclic derivatives resulting from a double addition reaction between sorbic acid and various amines. Mutagenesis studies, involving the Ames test and genotoxicity studies with HeLa cells and plasmid DNA, showed that none of the products studied presented either mutagenic or genotoxic activities. 相似文献
18.
Cavazzana-Calvo M Hacein-Bey S de Saint Basile G Gross F Yvon E Nusbaum P Selz F Hue C Certain S Casanova JL Bousso P Deist FL Fischer A 《Science (New York, N.Y.)》2000,288(5466):669-672
Severe combined immunodeficiency-X1 (SCID-X1) is an X-linked inherited disorder characterized by an early block in T and natural killer (NK) lymphocyte differentiation. This block is caused by mutations of the gene encoding the gammac cytokine receptor subunit of interleukin-2, -4, -7, -9, and -15 receptors, which participates in the delivery of growth, survival, and differentiation signals to early lymphoid progenitors. After preclinical studies, a gene therapy trial for SCID-X1 was initiated, based on the use of complementary DNA containing a defective gammac Moloney retrovirus-derived vector and ex vivo infection of CD34+ cells. After a 10-month follow-up period, gammac transgene-expressing T and NK cells were detected in two patients. T, B, and NK cell counts and function, including antigen-specific responses, were comparable to those of age-matched controls. Thus, gene therapy was able to provide full correction of disease phenotype and, hence, clinical benefit. 相似文献
19.
Yannick Roman Bertrand Bed'Hom Alain Guillot Julie Levrier Daniel Chaste‐Duvernoy Marie‐Claude Bomsel‐Demontoy Michel Saint Jalme 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2009,38(2):206-212
Background: Plasma protein electrophoresis is frequently used in birds as a tool for the diagnosis and monitoring of disease. Identification of proteins in individual peaks can help improve our understanding of changes in protein concentration in physiologic and pathologic conditions. Objective: The aim of this study was to verify the presence and identity the protein(s) in the prominent α‐globulin peak of orange‐winged parrots (Amazona amazonica), black kites (Milvus migrans), and rock pigeons (Columba livia). Methods: Heparinized plasma samples were obtained from 12 birds of each species. Agarose gel electrophoresis and total protein concentration were determined using standard techniques. One plasma sample from each species was then electrophoresed using high‐resolution agarose gels to isolate the α‐globulin band. Gel strips were digested in trypsin and peptides were extracted and analyzed using liquid chromatography with tandem mass spectrometry. De novo sequencing was used to identify the protein based on homology scoring against a protein database. Results: Electrophoresis verified the presence of a single prominent α‐globulin peak, usually in the α1‐region, that had a median concentration of 9.4 g/L (range, 2.1–11.7 g/L, 21.6% of total protein) in parrots, 12.2 g/L (10.4–13.2 g/L, 35.9%) in kites, and 10.7 g/L (9.0–11.5 g/L, 40.0%) in pigeons. Mass spectrometry and sequencing analysis unequivocally identified the protein as a mature circulating form of apolipoprotein A‐I (apo A‐I) in all 3 species. Conclusions: Apo A‐I accounts for the prominent α‐globulin peak and comprises a major proportion of total protein concentration in diverse avian species. As a high‐density lipoprotein and negative acute phase protein with a pivotal role in cholesterol homeostasis, further study is warranted to determine the significance of changes in apo A‐I concentration in avian electrophoretograms. 相似文献
20.
Prashant Vikram Jorge Franco Juan Burgueo Huihui Li Deepmala Sehgal Carolina Saint‐Pierre Cynthia Ortiz Vaibhav Kumar Singh Clay Sneller Achla Sharma Maria Tattaris Carlos Guzman Javier Pena Carolina Paola Sansaloni Jaime Amador Campos Serna Karthikeyan Thiyagarajan Guillermo Fuentes Davila Matthew Reynolds Kai Sonder Velu Govindan Marc Ellis Sridhar Bhavani Mohammad R. Jalal Kamali Mozaffar Roosatei Sanjay Singh Daisy Basandrai Navtej Singh Bains Ashwani Basandrai Thomas Payne Jos Crossa Sukhwinder Singh 《Plant Breeding》2021,140(1):87-99
Iranian wheat landrace accessions (IWAs) were collected from country‐wide farm fields and market places in 1935 by a professor at the University of Tehran and shared with University of California at Davis, California. IWAs were further submitted to the genebank of International Maize and Wheat Improvement Center (CIMMYT), Mexico. 2,403 IWAs from CIMMYT’s genebank were assayed by DArT‐seq technology to assess genetic diversity. No apparent ecogeographic patterns related to genetic diversity were detected, probably due to long‐term transport and frequent interchange of landraces among farmers. A multivariate clustering procedure combining genotypic and phenotypic information was used in selecting a core‐set, which represented 15% of the hexaploid wheat accessions included in this study. This subset captured an estimated 93% of rare (frequency <0.05) alleles. Multisite phenotypic data (India, Mexico) validated the ability of the core‐set in detecting useful variants. Potential donor accessions for multiple traits (disease resistance, zinc concentration) were identified from the core‐set for wheat‐breeding. This report illustrates a breeder friendly robust core‐set formulation strategy for harnessing the useful genetic variation stored in the genebanks. 相似文献