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981.
红杂18是以红213为母本,黄苗试材9375为父本,配制成适宜罐藏加工和长途运销的番茄一代杂种。具有高抗TMV、中抗CMV、果实硬度高、抗裂、耐压、耐贮运、果实加工性状优良等特点。已在新疆、甘肃、宁夏、广西、云南等省区的加工番茄生产基地和远运外销生产基地推广649.8hm2。  相似文献   
982.
A laboratory evaluation was performed to evaluate the performance characteristics of a new veterinary ventilator. The ventilator studied was configured according to manufacturer's directions and attached to a test lung via a pneumotachograph and differential pressure transducer interfaced to a pulmonary mechanics analyzer system. Constant resistance (R=10 cm H2O/L/sec) and compliance (C=3 ml/cm H2O) factors were maintained for all trials. The ventilator operated at the manufacturer's preprogrammed parameters. In the first trial, body weight was the only variable. In the second trial, an endotracheal tube was placed in series between the ventilator's breathing circuit and the pneumotachograph. Body weights from 1–20 kgs were evaluated. Mean values for respiratory rate (RR), minute ventilation (VE), inspiratory time (Ti), peak inspiratory pressure (PIP), and peak inspiratory flow (Fpki) displayed on the ventilator control panel; tidal volume (VT), calculated from the displayed minute volume, and identical parameters measured by the pulmonary mechanics system at each body weight, were compared using a two factor analysis of variance. Significant differences (P< 0.05) were found between mean displayed and measured values for RR, PIP, and Fpki.  相似文献   
983.
Abstract. In Australia, stubble burning and tillage are two of the major processes responsible for the decline of soil organic carbon concentration in cropped soils, and the resulting soil degradation. However, the relative importance of these two practices in influencing the soil organic carbon concentration and the long-term impact on soil quality and productivity are not clear. The effects of stubble burning as practised by farmers in southeastern Australia were evaluated in two field trials, one of 19 years duration, the other of 5 years. Conventional tillage (three tillage passes) led to greater loss of soil organic carbon than stubble burning. Loss of total soil organic carbon attributed to stubble burning in the 0–10 cm layer was estimated to be 1.75 t C ha−1 over the period of the 19-year trial, equivalent to 29% of that lost due to tillage. In the 5-year trial, no change in soil organic carbon due to stubble burning was detectable. Changes in soil quality associated with stubble burning detected in the longer trial included a reduction in macro-aggregate stability, and increases in pH and exchangeable K+. Only the latter two were detected in the shorter trial. A higher mean wheat yield (average 0.15 t ha−1) following stubble burning was observed in the 19-year trial but not in the 5-year trial. Research to monitor the longer term effects of stubble burning is needed, and to identify conditions where loss of soil organic carbon is minimized.  相似文献   
984.
After renal allografting, cyclosporin-A was administered to one partially nonmatched dog that was followed for 79 days. Cyclosporin-A and prednisolone were administered to one nonmatched dog that was followed for 805 days. Side effects encountered with cyclosporin-A included lymphocytic dermatitis, papillomatosis, bacterial and fungal infections, and B lymphocyte hyperplasia.  相似文献   
985.
A practical dilution method for determining the degree of susceptibility of aquatic Vibrio and Aeromonas spp. to antibacterial agents is described. The method utilizes the differential ability of these two genera to ferment glucose. Acidification produced by the bacterial metabolism is demonstrated by the color change of an indicator (bromthymol blue) from blue-green to bright yellow. Where bacteria are inhibited by a sufficient concentration of the antibacterial drug tested, no color change occurs. The accurate quantitative results obtained with this method facilitate proper therapy for diseased fish, shrimps and oysters. The same method can in principle be applied to any other glucose-fermenting bacteria, when challenged with non-acidic antibacterial agents.  相似文献   
986.
987.
ABSTRACT Cross‐country studies of education and economic prosperity often reach conflicting results when using growth rates as the measure of economic development. However, growth rates lack persistence over time and may not accurately measure long‐term economic success over relatively short economic horizons. To overcome this potential specification problem, we estimate the relationship between key education variables and the capital to physical labor ratio. Using both cross‐sectional and panel specifications, we find that both the primary‐pupil–teacher ratio and decentralized education finance are associated with a larger capital to physical labor ratio. The relationship between human capital and expenditures, private education, and test scores are less robust.  相似文献   
988.
Pharmacokinetic and Phase I Evaluation of Carboplatin in Dogs   总被引:1,自引:1,他引:0  
Thirty dogs with spontaneously occurring malignant neoplasms were treated monthly with carboplatin (CBDCA) given as a 30-minute intravenous infusion in a dose escalation study. Twenty-eight dogs were considered evaluable for toxicity. The maximally tolerated dose of CBDCA was conceptually defined as that dose, determined by logistic regression analyses of toxicity data, resulting in a 50% incidence of moderate toxicity (MOD50) or a 5% incidence of severe toxicity (SEV5). Each designated maximally tolerated dose was calculated for the first course of treatment only and for the first and second courses of treatment combined to estimate cumulative drug toxicity. The MOD50 and SEV5 for the first treatment course were 340 and 278 mg/M2, respectively. MOD50 and SEV5 values for the first plus second treatment courses were 327 and 231 mg/M2, respectively. The nadir of neutrophil and platelet counts occurred approximately 14 days after treatment. The mean neutrophil and platelet values for all dogs experiencing myelosuppression during the first two treatment courses were 1541/μL and 62,600/μL, respectively. Nonparametric pharmacokinetic analysis of plasma CBDCA values suggested that half-life (T1/2), area-under-the-curve and total body clearance (CLb) were not dose dependent. Volume of distribution (VDss) significantly increased with dose only between 100 and 150 mg/M2, not between 150 and 300 mg/M2. Dose-independent serum CBDCA pharmacokinetic disposition indicates that detailed investigation of tissue CBDCA distribution would be warranted and may identify novel dosing strategies that could improve the therapeutic index of CBDCA by minimizing toxicity. (Journal of Veterinary Internal Medicine 1993; 7:235–240. Copyright © 1993 by the American College of Veterinary Internal Medicine.)  相似文献   
989.
陶渊明和华兹华斯同出于对各自现实政治不满的目的 ,返始归根回到了自然。由于诗人分属于东西方完全不同的文化系统 ,且在各自的文学土壤上滋生、发展 ,因此在自然之中呈现出“无我”与“有我”的明显差异。  相似文献   
990.
J. Domínguez 《Plant Breeding》1996,115(3):203-204
The inheritance of resistance to a highly virulent population of sunflower broomrape (Orobanche cernua) has been studied in R-41, a Spanish sunflower restorer inbred line. Using the cytoplasmic male-sterile inbred line HA-89 (cms; very susceptible to this population of broomrape) as a female parent, progenies of the cross with R-41, i.e. Fl, F2 and BC1 to both parents, as well as the parental lines, were analysed for their reaction to the broomrape population EC-94. The goodness of fit of the observed vs expected segregation ratios indicated that the inheritance of resistance to broomrape in line R-41 is conferred by two independent dominant genes.  相似文献   
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