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排序方式: 共有332条查询结果,搜索用时 31 毫秒
41.
Beckman BW 《Journal of veterinary dentistry》2004,21(3):159-163
This case report describes the use synthetic bone graft particulate and 24% EDTA gel to treat an infrabony defect adjacent to the mandibular right first molar tooth in an American Eskimo dog. Postoperative examination 33-months following surgery showed osseous integration at the infrabony defect and restoration of the periodontal ligament space with a small refractory periodontal pocket. 相似文献
42.
Radcliffe CH Woodie JB Hackett RP Ainsworth DM Erb HN Mitchell LM Soderholm LV Ducharme NG 《Veterinary surgery : VS》2006,35(7):643-652
OBJECTIVE: To compare upper airway mechanics, arterial blood gases, and tracheal contamination in horses with induced left laryngeal hemiplegia (recurrent laryngeal neuropathy [RLN]) treated by laryngoplasty/vocal cordectomy (LPVC) or modified partial arytenoidectomy (MPA). STUDY DESIGN: Repeated measures under the following conditions: Control, RLN, LPVC, and MPA. ANIMALS: Six horses. METHODS: Two trials were conducted under all conditions at 80% and 100% of maximal heart rate (HR(max)). In Trial 1, arterial blood gases, tracheal and pharyngeal pressures, and laryngeal videoendoscopy were recorded. In Trial 2, upper airway pressure and airflow were determined. Tracheobronchial aspirates were performed after exercise to quantify airway contamination. RESULTS: Compared with control, RLN significantly increased inspiratory impedance and worsened exercise-induced hypoxemia. At 80% HR(max), LPVC restored most variables to control values. At 100% HR(max), LPVC improved all variables, but did not restore minute volume, arterial pH, and PaCO(2). At 80% HR(max), MPA restored all variables except bicarbonate to control values. At 100% HR(max), MPA improved all variables, but did not statistically restore minute ventilation or bicarbonate level. Only minor differences were noted between LPVC and MPA. Both resulted in equivalent tracheal contamination. CONCLUSIONS: Airway mechanics and arterial blood gas values were not restored to normal after either LPVC or MPA in horses exercising at HR(max). This does not affect ventilation at sub-maximal exercise, but has clinical implications at HR(max). Both procedures diminish normal laryngeal protective mechanisms. CLINICAL RELEVANCE: At sub-maximal exercise intensities both LPVC and MPA restore airway ventilation to normal. At maximal exercise the superiority of LPVC over MPA is slight. 相似文献
43.
Baker BJ Tyson GW Webb RI Flanagan J Hugenholtz P Allen EE Banfield JF 《Science (New York, N.Y.)》2006,314(5807):1933-1935
Novel, low-abundance microbial species can be easily overlooked in standard polymerase chain reaction (PCR)-based surveys. We used community genomic data obtained without PCR or cultivation to reconstruct DNA fragments bearing unusual 16S ribosomal RNA (rRNA) and protein-coding genes from organisms belonging to novel archaeal lineages. The organisms are minor components of all biofilms growing in pH 0.5 to 1.5 solutions within the Richmond Mine, California. Probes specific for 16S rRNA showed that the fraction less than 0.45 micrometers in diameter is dominated by these organisms. Transmission electron microscope images revealed that the cells are pleomorphic with unusual folded membrane protrusions and have apparent volumes of <0.006 cubic micrometer. 相似文献
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Tetrodotoxin (TTX) is a neurotoxin that has been reported from taxonomically diverse organisms across 14 different phyla. The biogenic origin of tetrodotoxin is still disputed, however, TTX biosynthesis by host-associated bacteria has been reported. An investigation into the culturable microbial populations from the TTX-associated blue-ringed octopus Hapalochlaena sp. and sea slug Pleurobranchaea maculata revealed a surprisingly high microbial diversity. Although TTX was not detected among the cultured isolates, PCR screening identifiedsome natural product biosynthesis genes putatively involved in its assembly. This study is the first to report on the microbial diversity of culturable communities from H. maculosa and P. maculata and common natural product biosynthesis genes from their microbiota. We also reassess the production of TTX reported from three bacterial strains isolated from the TTX-containing gastropod Nassarius semiplicatus. 相似文献
48.
Murphy Richard J. Whelan Brett Chlingaryan Anna Sukkarieh Salah 《Precision Agriculture》2019,20(4):767-787
Precision Agriculture - Variations in water absorption across lettuce leaves (Latuca sativa L. var. longifolia) were quantified from hyperspectral imagery acquired in the laboratory using selected... 相似文献
49.
Genqiao Li Xiangyang Xu Chengcheng Tan Brett F.Carver Guihua Bai Xuewen Wang J.Michael Bonman Yanqi Wu Robert Hunger Christina Cowger 《作物学报(英文版)》2019,(3):294-306
Wheat powdery mildew(Blumeria graminis f.sp.tritici, Bgt) is a disease of increasing importance globally due to the adoption of high yielding varieties and modern sustainable farming technologies.Growing resistant cultivars is a preferred approach to managing this disease, and novel powdery mildew resistance genes are urgently needed for new cultivar development.A genome-wide association study was performed on a panel of 1292 wheat landraces and historical cultivars using 5011 single nucleotide polymorphism(SNP)markers.The association panel was evaluated for reactions to three Bgt inoculants, OKS(14)-B-3-1, OKS(14)-C-2-1, and Bgt15.Linkage disequilibrum(LD) analysis indicated that genome-wide LD decayed to 0.1 at 23 Mb, and population structure analysis revealed seven subgroups in the panel.Association analysis using a mixed linear model(MLM) identified three loci for powdery mildew resistance on chromosome 2 B, designated QPm.stars-2BL1,QPm.stars-2BL2, and QPm.stars-2BL3.To evaluate the efficacy of GWAS in gene discovery,QPm.stars-2BL2 was validated using F2 and F2:3 populations derived from PI420646 × OK1059060-126135-3.Linkage analysis delimited the powdery mildew resistance gene in PI 420646 to an interval where QPm.stars-2BL2 was located, lending credence to the GWAS results.QPm.stars-2BL1 and QPm.stars-2BL3, which were associated with four SNPs located at 457.7–461.7 Mb and two SNPs located at 696.6–715.9 Mb in the Chinese Spring reference IWGSC RefSeq v1.0, respectively, are likely novel loci for powdery mildew resistance and can be used in wheat breeding to improve powdery mildew resistance. 相似文献
50.
This paper examines the potential influence of soil management and land use on soil carbon on cropping farms in New South Wales (NSW), Australia. Soil organic carbon (SOC) data from ten farms spatially distributed across NSW were examined on two occasions. Soil cores to a depth 0–30 cm were measured for SOC and, as expected, SOC in the A horizon (1.16%) was significantly (p < .001) greater than in the B horizon (0.74%) of all profiles. Analysis of the 2013 and 2015 SOC data indicated that in many ways, the results runs counter to other SOC studies in Australia. Importantly, the mean SOC concentration in these agricultural soils was significantly (p < .001) less under cropping (2013-1.05%, 2015-0.97%) than in native sites (2013-1.20%, 2015-1.16%). Out of the total of 35 sites sampled from 10 farms, SOC in 49% of sites did not change significantly over 2 years, in 17% it increased significantly, whereas in 34% it decreased. Further, a clear implication of drought on SOC was seen on sites that were uncropped based on a critical value for a 95% confidence interval (p < .05) and complemented by the significant correlation (p < .05) between average annual precipitation deficit (ANPD) and SOC across the state with R2 = 0.39. The mean SOC was found to be directly proportional to standard deviation and standard error. In terms of spatial variability, the C0 (nugget) value was greatest for farms with a large mean SOC and the average variogram in this study has a range of approximately 200 m which is potentially useful in determining sampling spacing for soil carbon auditing purpose. Similar empirical data over more years are required to better estimate SOC levels and to determine whether at a farm scale, factors such as land management, land use and climate can be related to soil carbon change and variability. 相似文献