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81.
Treatment of proximal hind-limb lameness in cattle   总被引:2,自引:0,他引:2  
Lameness of the hind limb (tarsus and proximal) in cattle is considered from the viewpoint of diagnosis and prognosis. Indications and techniques for radiography are discussed, as well as when indicated.  相似文献   
82.
OBJECTIVE: To determine the impact of successive days of endurance exercise on select serum chemistry values in conditioned Alaskan sled dogs. DESIGN: Prospective cohort study. ANIMALS: 10 conditioned Alaskan sled dogs. PROCEDURES: All dogs ran 160 km/d for 5 consecutive days. Serum was obtained prior to exercise and immediately after each exercise run; all samples were obtained before dogs were fed. Serum electrolyte, mineral, protein, total bilirubin, urea nitrogen, creatinine, and cardiac troponin-I concentrations and serum alkaline phosphatase, alanine aminotransferase, creatine kinase, and aspartate aminotransferase activities were measured. Data were analyzed by means of analysis of covariance for a randomized complete block design with dog as a blocking variable, time as a covariate, and distance run as the treatment of interest. Least square mean values were compared with values obtained prior to exercise, and linear and quadratic contrasts were examined. RESULTS: Serum globulin concentration was low prior to exercise (mean +/- SD, 2.2 +/- 0.3g/dL) and progressively decreased as exercise continued. Exercise was associated with increases in serum chloride, urea nitrogen, and cardiac troponin-I concentrations and serum alanine aminotransferase, creatine kinase, and aspartate aminotransferase activities and with progressive decreases in serum potassium, total protein, and albumin concentrations. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that multiple successive days of endurance exercise resulted in mild aberrations in serum chemistry variables in conditioned sled dogs. Changes likely reflected the metabolic stresses of prolonged endurance exercise as well as dietary composition. Hypoglobulinemia in resting, conditioned sled dogs may reflect the immunosuppressive or catabolic effects of intense endurance training.  相似文献   
83.
A simplified protocol to obtain fatty acid methyl esters (FAME) directly from fresh tissue, oils, or feedstuffs, without prior organic solvent extraction, is presented. With this protocol, FAME synthesis is conducted in the presence of up to 33% water. Wet tissues, or other samples, are permeabilized and hydrolyzed for 1.5 h at 55 degrees C in 1 N KOH in MeOH containing C13:0 as the internal standard. The KOH is neutralized, and the FFA are methylated by H(2)SO(4) catalysis for 1.5 h at 55 degrees C. Hexane is then added to the reaction tube, which is vortex-mixed and centrifuged. The hexane is pipetted into a gas chromatography vial for subsequent gas chromatography. All reactions are conducted in a single screw-cap Pyrex tube for convenience. The method meets many criteria for fatty acid analysis, including not isomerizing CLA or introducing fatty acid artifacts. It is applicable to fresh, frozen, or lyophilized tissue samples, in addition to oils, waxes, and feedstuffs. The method saves time and effort and is economical when compared with other methods. Its unique performance, including easy sample preparation, is achieved because water is included rather than eliminated in the FAME reaction mixtures.  相似文献   
84.
中国水稻白叶枯病菌系染色体DNA的RFLP谱型的初析   总被引:5,自引:0,他引:5  
章琦 Leach  JE 《作物学报》1996,22(1):13-19
用2个DNA探针pJEL101和pBASavrXa10对78个水稻白叶枯病菌系进行RFLP分型,以分析其群体结构和遗传多样性。分别鉴定出16种RFLP标记带的谱型。以彼此的带位相似率达85%为界,可分为簇。参试菌系的群体遗传多样性为0.77(用pJEL101),和0.83RFLP谱型分析表明:我国多数病原型为杂合组群。白叶枯病菌系的分子表现型的变异,远远大于致病型,两个探针都能有效分析我国菌系的群  相似文献   
85.
OBJECTIVE: The effectiveness of geographic targeting in nutrition programmes depends largely on the degree to which malnutrition clusters within particular areas. This study investigates the extent to which the childhood nutrition indicators, stunting (height-for-age Z-score <-2) and wasting (weight-for-height Z-score <-2), are spatially clustered; this information is used to determine the implications of spatial clustering for the effectiveness of geographic targeting. DESIGN: Analysis of data from Demographic and Health Survey (DHS) results. Clustering is assessed by calculating intra-cluster correlation coefficients (ICCs). Estimating the proportion of malnourished children covered by a programme successfully targeting 10% of clusters with the highest malnutrition prevalences allows an assessment of the effectiveness of geographic targeting. SETTING: Fifty-eight DHS III (1992-1997) and DHS IV (1998-2001) reports from 46 developing countries. SUBJECTS: Pre-school children of mothers interviewed by DHS. MAIN RESULTS: The extent of clustering of nutritional status was surprisingly low (median ICC for national samples: stunting=0.054, wasting=0.032) and most countries were characterised by having an ICC <0.1--i.e. low clustering--for childhood undernutrition (91% of countries for wasting and 78% for stunting). Our assessment of the effectiveness of geographic targeting showed that coverage was better for wasting than for stunting; for wasting, 23% of countries would achieve less than 20% coverage, compared with 76% of countries achieving less than 20% coverage for stunting. Coverage is dependent on the overall prevalence of malnutrition and the ICC. CONCLUSIONS: Childhood nutritional status is determined at the household, or even individual, level; nutrition programmes that are geographically targeted may result in high levels of under-coverage and leakage, thereby compromising their cost-effectiveness; the lack of clustering questions the appropriateness of current nutrition interventions.  相似文献   
86.
Physical properties of field soil vary both spatially and temporally. Because so little information is available concerning the changes in magnitude of soil physical properties as functions of soil depth, distance normal to a crop row, and time, they have largely been ignored in model development. The purpose of this study was to evaluate quantitatively the spatial and temporal variability imposed by several tillage operations on several soil physical properties. Three tillage treatments, replicated 4 times in a randomized complete block design, were (1) conventionally-disked 3 times before planting, (2) full width strip chisel plowed to a 27-cm depth, and (3) in-row-subsoiled plus bedding. Soil physical properties measured were cone index (CI), weight percentage water (Pw), bulk density (Db), soil water characteristic curve, saturated hydraulic conductivity (Ksat) and soil settling. These properties were measured 3 times: immediately after planting soybeans (Glycine max (L.) Merr.) on 16 May; on 3 June; on 8 July 1977. Soil properties were measured at the 0–14, 14–28, and 28–41-cm soil depths at 3 positions relative to the row i.e., in the row, in the trafficked interrow, and in the non-trafficked interrow. Significant differences due to tillage treatment were found for Db, CI, and the soil water characteristic. The greatest spatial variation occurred in the 0–14-cm depth and decreased with depth. Significant differences for most variables were also found for the tillage by depth and tillage by position interactions. All properties exhibited significant temporal variation.  相似文献   
87.
Use of lead glazes on ceramicware and the release of lead from finished glazes are reviewed. Single units of ceramicware with initial lead leach levels from less than 0.1 to 470 micrograms/mL were subjected to multiple automatic dishwashings with intermediate scrubbing of the ware by plastic fiber pads. Ware was periodically leached with 4% acetic acid solution at room temperature for 24 h, and the solutions were analyzed for lead. Release of lead under these conditions is discussed. Results indicated that neither passive leachings nor multiple dishwashings and scrubbings can predict future lead-release characteristics of glazes and decorations.  相似文献   
88.
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   
89.
90.
The mechanisms controlling axon guidance are of fundamental importance in understanding brain development. Growing corticospinal and somatosensory axons cross the midline in the medulla to reach their targets and thus form the basis of contralateral motor control and sensory input. The motor and sensory projections appeared uncrossed in patients with horizontal gaze palsy with progressive scoliosis (HGPPS). In patients affected with HGPPS, we identified mutations in the ROBO3 gene, which shares homology with roundabout genes important in axon guidance in developing Drosophila, zebrafish, and mouse. Like its murine homolog Rig1/Robo3, but unlike other Robo proteins, ROBO3 is required for hindbrain axon midline crossing.  相似文献   
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