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991.
After comparison of Trichoderma population density and test of colonization ability in rhizospheres were conducted. Auxotrophic mutants of T. harzianum tolerant to carbendazim and UV-light were obtained by UV-light mutagenesis and carbendazim stress on PDA medium and a basis medium with hot pepper root exudation by adding the fungicide. The results showed: all four different isolates of Trichoderma had certain colonization ability in rhizosphere with the characteristic of growing as… 相似文献
992.
993.
P Russo C Vitu M Lambert A Giauffret 《Comparative immunology, microbiology and infectious diseases》1979,2(1):75-85
The chlamydia order comprises two species (Chlamydia trachomatis and Chlamydia psittaci) which are the only ones which can be rigorously differentiated with experimental criteria. However, the clinical study of chlamydia demonstrates the existence of various syndromes due to pathogenic agents. Some observations also seem to indicate the possibility of antigenic differences between isolated strains, during abortions, among small ruminants.We have entered upon a comparative study of various Chlamydia psittaci strains in order to look for objective criteria of differentiation of the strains extracted from small ruminants from those which were isolated from other animal species. Chlamydia taken from samples of ovine and caprine origin by direct isolation on embryonated egg or on cellular cultures were also compared by the following methods: seroneutralization on embryonated eggs and on cell cultures, characteristics of the plaques on cell cultures, crossed-immunofluorescence, toxic effects, lethal action on the foetus of the pregnant mouse, crossed-immunoelectrophoresis by agar gel (simple or double quantitative diffusion), electrophoresis by polyacrylamide gel.The use of those numerous techniques has enabled us to observe significant differences between those strains. However, it is not yet possible to propose a classification defining several groups. The specificity of these differences, especially between ovine and caprine strains, should become clear through the studies now in progress: in particular through the method using the interference of specific antigens compared on the one hand by serioimmunologic methods and, on the other hand, by tests setting an immunity to cellular mediation into action. 相似文献
994.
Ferasin L Dodkin SJ Amodio A Murray JK Papasouliotis K 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2007,36(1):36-39
BACKGROUND: Measurement of blood lactate concentration has become a common practice in canine medicine. However, the accuracy of portable lactate monitors has not been reported in dogs. OBJECTIVES: The aim of this study was to evaluate the accuracy and precision of a portable analyzer (Lactate-Scout) in measuring canine blood lactate concentration. METHODS: A preliminary study was performed to assess the effects of sample storage time and temperature on plasma lactate concentration. Blood samples obtained from 6 canine patients at our hospital were divided into 8 aliquots and stored at 4 degrees C and 20 degrees C; plasma lactate was measured in duplicate with a spectrophotometric system (Konelab) at 0, 30, 60, 120, and 240 minutes after the blood collection. Values were compared with those obtained immediately after blood collection. Lactate values obtained by the portable method also were compared with those obtained by the reference spectrophotometric analyzer on blood samples collected from 48 additional canine patients. RESULTS: There was no significant effect of storage time (P = .89) or temperature (P = .51) on plasma lactate levels. The correlation between lactate values measured with the Lactate-Scout and the Konelab method was r = .98 (slope = .81, 95% confidence interval = .73-.87; intercept = .20, 95% confidence interval = .13-.31). The level of agreement between the 2 methods was generally good for mean lactate concentrations <5 mmol/L. However, at higher lactate concentrations (5 of 48 samples), the values recorded by the Lactate-Scout analyzer were lower than those measured by the Konelab method. CONCLUSION: The Lactate-Scout analyzer is reliably comparable to a reference method for measuring whole blood lactate concentration in dogs; however, caution should be used when interpreting lactate values of 5 mmol/L and higher. 相似文献
995.
Roleff S Arndt G Bottema B Junker L Grabner A Kohn B 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2007,36(2):155-166
BACKGROUND: The CA530-VET is a completely automated impedance cell hematology analyzer, which yields a 16-parameter blood count including a 3-part leukocyte differential. OBJECTIVES: The aim of this study was to examine the operational potential of the CA530-VET and its value for use in veterinary practice. METHODS: The analyzer was tested for blood carry-over, precision, and accuracy. Comparison methods included the CELL-DYN 3500, microhematocrit centrifugation, manual platelet (PLT) counting for feline and equine species, and a 100-cell manual WBC differential. Blood samples for comparison of the methods were obtained from 242 dogs, 166 cats, and 144 horses. RESULTS: The carry-over ratio (K) was 0.28% for RBC, 0.59% for PLT, 0.32% for WBC, and 0.18% for hemoglobin (HGB) concentration. Coefficients of variation (CVs) for within-batch precision and duplicate measurement of blood samples were clearly within the required limits, except for duplicate platelet counts in cats (8.7%) and horses (9.5%). The WBC count was in excellent agreement for dogs and horses and RBC count was in excellent agreement for horses. The accuracy of feline WBC counts was not acceptable, with the exception of values at the high end of the range. RBC counts in dogs and cats, and HGB concentration and MCV in all 3 species were sufficiently accurate. The CA530-VET HCT results were in excellent agreement with microhematocrit results in horses but exceeded the maximum allowed inaccuracy for cats and dogs. In all species, PLT counts established mechanically and manually were not in adequate agreement. Large differences were found between the CA530-VET and the manual differential percentage for lymphocytes and "mid-sized cells" (monocytes and basophilic granulocytes). CONCLUSIONS: The CA530-VET can be considered useful for routine canine, feline, and equine blood cell analyses. It should not be considered accurate, however, for PLT counts, feline total WBC counts in the subnormal and normal range, and leukocyte differentials, except for granulocytes. 相似文献
996.
在过于浓厚的"辨异"语境下,国内法学界大都认可这样一种判断:西方自然法学和分析法学的学说主张是彼此对立、"水火不容"的。其实,此二学派在法律基本精神、思维方式等许多重要问题上存在着广泛而深刻的相同相通相似之处。因此,判定二者"水火不容"显然是偏颇的,它是国内法学比较研究忽视"求同"、片面"辨异"的产物。由此,应该对国内法学比较研究这种畸轻畸重的视角问题作出反思与批判,从而突显法学比较的"求同"维度。 相似文献
997.
Total nucleated cell and leukocyte differential counts in canine pleural and peritoneal fluid and equine synovial fluid samples: comparison of automated and manual methods
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998.
Antimicrobial resistance in bacteria from horses: Epidemiology of antimicrobial resistance
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T. W. Maddox P. D. Clegg N. J. Williams G. L. Pinchbeck 《Equine veterinary journal》2015,47(6):756-765
Antimicrobial resistance poses a significant threat to the continued successful use of antimicrobial agents for the treatment of bacterial infections. While the epidemiology of antimicrobial resistance in bacteria from man has been studied extensively, less work has been undertaken in companion animals, particularly horses. Methicillin‐resistant Staphylococcus aureus has been identified as a cause of infections, with a low prevalence of nasal carriage by horses in the community but higher for hospitalised horses. Molecular characterisation has shown methicillin‐resistant Staphylococcus aureus strains either to be predominantly of types associated with horses or of sequence type ST398. Antimicrobial‐resistant Escherichia coli (including multidrug‐resistant and extended spectrum β‐lactamase‐producing isolates) have caused infections and been documented in faecal carriage by horses, with many significant resistance mechanisms identified. More sporadic reports and molecular characterisation exist for resistance in other bacteria such as enterococci, Salmonella, Acinetobacter and Pseudomonas species. Limited work has been undertaken evaluating risk factors and much of the epidemiology of antimicrobial resistance in bacteria from horses remains to be determined. 相似文献
999.
持续极端高温干旱天气对大花萱草生长的影响 总被引:3,自引:0,他引:3
2013年夏天宁波遭遇60年来最高气温,持续时间较长且干旱少雨,本研究对宁波天气情况、18份大花萱草(Hemerocallis hybridus)材料的受害情况及其受害后的恢复情况等进行了记载观察。持续高温干旱的情况下大花萱草材料在田间表现存在较大差异,耐高温干旱能力强的材料生长未受影响,耐受性较弱的材料叶片出现枯黄萎蔫。经过筛选,以生长状况、热害指数、越夏成活率、整体姿态、叶色、观赏价值作为耐热性田间鉴定有效指标。并利用灰色关联分析法对田间的18份大花萱草材料进行了耐热性鉴定。结果表明,X16、X8、X11和X15耐热性较强,与理想耐热品种的关联度超过0.9,适合在宁波地区推广栽培;耐热性较差的材料X1、X18和X12,因其恢复较快,可以以林下地被花卉的形式进行配置和应用。 相似文献
1000.
Zinc Oxide Therapy Increases Prevalence and Persistence of Methicillin‐Resistant Staphylococcus aureus in Pigs: A Randomized Controlled Trial
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There is concern that therapeutic use of zinc oxide (ZnO) in swine production may select for methicillin‐resistant Staphylococcus aureus (MRSA) due to co‐location of the zinc resistance gene (czrC) and methicillin resistance gene (mecA) within the staphylococcal cassette chromosome mec (SCCmec). The objective of this investigation was to determine whether MRSA carriage in pigs is influenced by exposure to therapeutic doses of in‐feed ZnO (3000 mg/kg) when compared to the recommended dietary levels (100 mg/kg). A randomized controlled trial was completed using 110 pigs that were naturally colonized with czrC‐positive MRSA. The pigs were followed from birth to weaning (21 d), at which point they were randomized into 8 pens and exposed to either a control feed (100 mg ZnO/kg feed; n = 49 pigs) or a treatment feed (3000 mg ZnO/kg feed; n = 50 pigs); neither feed contained additional antimicrobials. MRSA carriage was monitored weekly in each group for 4 weeks post‐weaning. The prevalence of MRSA was significantly higher in the treatment group at 1‐week (OR = 18.1; P < 0.01) and 2 weeks (OR = 3.01; P = 0.01) post‐weaning when compared to the control group, but there was no difference later in the nursery phase. Persistent MRSA carriage (testing positive ≥2 times post‐weaning) was observed in 2% (1/49) of control pigs and 22% (11/50) of treated pigs (P < 0.01). All MRSA isolates (spa types t034 and t3075) carried czrC and showed uniform resistance to zinc. These findings demonstrate that the prevalence and persistence of MRSA in nursery pigs can be affected by high levels of in‐feed ZnO in the absence of antibiotics. 相似文献