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81.
Neil KM Axon JE Todhunter PG Adams PL Caron JP Adkins AR 《Journal of the American Veterinary Medical Association》2007,230(11):1683-1690
OBJECTIVE: To determine the clinical characteristics and outcome of foals with septic osteitis of the distal phalanx. DESIGN: Retrospective case series. ANIMALS: 22 foals. PROCEDURES: Information obtained from medical records included signalment; clinical, laboratory, and radiographic findings; treatment method; and outcome. Foals included in the study had lameness referable to the foot, radiographic evidence of localized lysis or focal loss of bone density of the distal phalanx, and suppurative discharge or necrosis of the affected bone evident at surgery. Foals with a history or evidence of penetrating wounds or subsolar abscessation were excluded. RESULTS: Mean age of foals at initial evaluation was 40.8 days (range, 3 to 122 days). Twenty-one (95%) foals had lameness as the primary complaint. Lesions consistent with septic osteitis of the distal phalanx localized to specific areas of the bone on the basis of radiographic and surgical findings were located on the solar margin or toe (14/22 [64%]), extensor process (5/22 [23%]), and palmar or plantar process (3/22 [13%]). Hind limbs (18/26 [69%] affected limbs) were more frequently affected. Two foals had > 1 affected limb, 2 had additional sites of osteomyelitis, and 4 had concurrent septic arthritis. Surgical debridement and regional antimicrobial perfusion were performed during general anesthesia. Extensor process lesions were not debrided. Nineteen of 22 (86%) foals survived to be discharged from hospital, and 16 horses reached racing age. Eleven of 16 had race starts, of which 8 had official race starts and 3 had unofficial race starts. CONCLUSIONS AND CLINICAL RELEVANCE: Septic osteitis of the distal phalanx should be considered as a source of lameness in foals with signs referable to the foot and does not necessarily preclude a career in racing. Although infection may occur secondary to bacterial penetration of the hoof or sole, the distal phalanx should also be considered as a potential site for hematogenous septic arthritis or osteomyelitis in foals. 相似文献
82.
Summary A knowledge of the biological and functional relationships among traits would be of benefit to plant breeders in the choice of traits to use for increasing efficiency of selection in a breeding program. Principal factor analysis was used to identify biological and functional relationships among dry bean (Phaseolus vulgaris L.) traits in segregating populations of a phenotypic recurrent selection program designed to introduce upright architecture into medium-sized dry bean.Two biological interpretations were assigned to factors extracted in the analysis of four seed/pod traits. The first was a size factor, loaded with seed weight and pod width, and the second a number factor, which was loaded with number of seeds per pod and pod length. Similarly, three factors were extracted from the analysis of fifteen architectural traits. The first factor was interpreted as an elongation factor, and was loaded with internode length measurements, while the second factor was interpreted as a structural factor, and was further divided into two subclasses namely, sturdiness factor and profile factor. The sturdiness factor comprised hypocotyl diameter and hypocotyl length, while the profile factor comprised branch angle and number of basal branches. The third factor which was called a reproductive factor was loaded with pod distribution traits and the number and location of nodes on which pods were borne. 相似文献
83.
W M Adams 《Journal of the Association of Official Analytical Chemists》1983,66(5):1178-1181
The ion-pair partition properties of mefenamic acid with the methyl, ethyl, n-propyl, and n-butyl homologs of tetraalkylammonium cation were studied in relation to a model of an assay procedure for acidic drugs. Variables studied included identity and concentration of pairing ion and composition of extracting solvents. Resulting data were used to develop a partition chromatographic assay procedure. Standard recoveries averaged 99.01 +/- 0.82%. Assays of commercial capsules were reproducible. 相似文献
84.
Experiments were conducted to study the effects of a range of CO2 concentrations (ambient to 100%) on nitrification, denitrification and associated nitrous oxide (N2O) production in a silt loam soil. It was found that increase in CO2 concentration from 0.3 to 100% CO2 increasingly retarded the rate of nitrification. No nitrification occurred at 100% CO2. Nitrous oxide production associated with nitrification increased as CO2 increased from 0.3 to 2.6% and tended to be greater as CO2 concentration increased to 73%. At 100% CO2, no N2O was produced during 7 days at 25°C.Carbon dioxide did not affect N2O production or reduction in a saturated NO3?amended soil or the rate of N2O reduction in anaerobic environments. 相似文献
85.
Adams RL Mottram DS Parker JK Brown HM 《Journal of agricultural and food chemistry》2001,49(9):4333-4336
The irreversible binding of selected sulfur-containing flavor compounds to proteins was investigated in aqueous solutions containing ovalbumin and a mixture of disulfides (diethyl, dipropyl, dibutyl, diallyl, and 2-furfuryl methyl) using solid-phase micro-extraction (SPME). In systems which had not been heated, the recovery of disulfides from the headspace above the protein at the native pH (6.7) was similar to that from an aqueous blank. However, significant losses were observed when the pH of the solution was increased to 8.0. When the protein was denatured by heating, much greater losses were observed and some free thiols were produced. In similar heat-denatured systems at pH 2.0, no losses of disulfides were observed. Disulfides containing allyl or furfuryl groups were more reactive than saturated alkyl disulfides. Interchange reactions between protein sulfhydryl groups and the disulfides are believed to be responsible for the loss of the disulfides. 相似文献
86.
Campbell John L. Hornbeck James W. Mitchell Myron J. Adams Mary Beth Castro Mark S. Driscoll Charles T. Kahl Jeffrey S. Kochenderfer James N. Likens Gene E. Lynch James A. Murdoch Peter S. Nelson Sarah J. Shanley James B. 《Water, air, and soil pollution》2004,151(1-4):373-396
Input-output budgets for dissolved inorganic nitrogen (DIN) are summarized for 24 small watersheds at 15 locations in the northeasternUnited States. The study watersheds are completely forested, free of recent physical disturbances, and span a geographical region bounded by West Virginia on the south and west, and Maine on the north and east. Total N budgets are not presented; however, fluxes of inorganic N in precipitation and streamwater dominate inputs and outputs of N at these watersheds. The range in inputs of DIN in wet-only precipitation from nearby National Atmospheric Deposition Program (NADP) sites was 2.7 to 8.1 kg N ha-1 yr-1 (mean = 6.4 kg N ha-1 yr-1; median = 7.0 kg N ha-1 yr-1). Outputs of DIN in streamwater ranged from 0.1 to 5.7 kg N ha-1 yr-1 (mean = 2.0 kg N ha-1 yr-1; median = 1.7 kg N ha-1 yr-1). Precipitation inputs of DIN exceeded outputs in streamwater at all watersheds, with net retention of DIN ranging from 1.2 to 7.3 kg N ha-1 yr-1 (mean = 4.4 kg N ha-1 yr-1; median = 4.6 kg N ha-1 yr-1). Outputs of DIN in streamwater were predominantly NO3-N (mean = 89%; median = 94%). Wet deposition of DIN was not significantly related to DIN outputs in streamwater for these watersheds. Watershed characteristics such as hydrology, vegetation type, and land-use history affect DIN losses and may mask any relationship between inputs and outputs. Consequently, these factors need to be included in the development of indices and simulation models for predicting 'nitrogen saturation' and other ecological processes. 相似文献
87.
88.
Gaietta G Deerinck TJ Adams SR Bouwer J Tour O Laird DW Sosinsky GE Tsien RY Ellisman MH 《Science (New York, N.Y.)》2002,296(5567):503-507
Recombinant proteins containing tetracysteine tags can be successively labeled in living cells with different colors of biarsenical fluorophores so that older and younger protein molecules can be sharply distinguished by both fluorescence and electron microscopy. Here we used this approach to show that newly synthesized connexin43 was transported predominantly in 100- to 150-nanometer vesicles to the plasma membrane and incorporated at the periphery of existing gap junctions, whereas older connexins were removed from the center of the plaques into pleiomorphic vesicles of widely varying sizes. Selective imaging by correlated optical and electron microscopy of protein molecules of known ages will clarify fundamental processes of protein trafficking in situ. 相似文献
89.
Subcellular calcium transients visualized by confocal microscopy in a voltage-clamped vertebrate neuron 总被引:25,自引:0,他引:25
Confocal laser-scanned microscopy and long-wavelength calcium (Ca2+) indicators were combined to monitor both sustained and rapidly dissipating Ca2+ gradients in voltage-clamped sympathetic neurons isolated from the bullfrog. After a brief activation of voltage-dependent Ca2+ channels, Ca2+ spreads inwardly, and reaches the center of these spherical cells in about 300 milliseconds. Although the Ca2+ redistribution in the bulk of the cytosol could be accounted for with a radial diffusion model, local nonlinearities, suggesting either nonuniform Ca2+ entry or spatial buffering, could be seen. After electrical stimulation, Ca2+ signals in the nucleus were consistently larger and decayed more slowly than those in the cytosol. A similar behavior was observed when release of intracellular Ca2+ was induced by caffeine, suggesting that in both cases large responses originate from Ca2+ release sites near or within the nucleus. These results are consistent with an amplification mechanism involving Ca2(+)-induced Ca2+ release, which could be relevant to activity-dependent, Ca2(+)-regulated nuclear events. 相似文献
90.
Complementary DNA sequencing: expressed sequence tags and human genome project 总被引:227,自引:0,他引:227
M D Adams J M Kelley J D Gocayne M Dubnick M H Polymeropoulos H Xiao C R Merril A Wu B Olde R F Moreno 《Science (New York, N.Y.)》1991,252(5013):1651-1656
Automated partial DNA sequencing was conducted on more than 600 randomly selected human brain complementary DNA (cDNA) clones to generate expressed sequence tags (ESTs). ESTs have applications in the discovery of new human genes, mapping of the human genome, and identification of coding regions in genomic sequences. Of the sequences generated, 337 represent new genes, including 48 with significant similarity to genes from other organisms, such as a yeast RNA polymerase II subunit; Drosophila kinesin, Notch, and Enhancer of split; and a murine tyrosine kinase receptor. Forty-six ESTs were mapped to chromosomes after amplification by the polymerase chain reaction. This fast approach to cDNA characterization will facilitate the tagging of most human genes in a few years at a fraction of the cost of complete genomic sequencing, provide new genetic markers, and serve as a resource in diverse biological research fields. 相似文献