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921.
Correlation analysis of mineral element contents and quality traits in milled rice (Oryza stavia L.)
Jiang SL Wu JG Feng Y Yang XE Shi CH 《Journal of agricultural and food chemistry》2007,55(23):9608-9613
The relationships among potassium (K), calcium (Ca), sodium (Na), magnesium (Mg), iron (Fe), zinc (Zn), copper (Cu), and manganese (Mn) contents in milled rice (Oryza stavia L.) of 274 genotypes and the relationships between these mineral element contents and other rice quality traits including 3 cooking quality traits, 17 amino acid contents, and protein content were investigated. The results showed that there were significant correlations among most of mineral element contents. Mg, Fe, and Mn contents were significantly correlated with most of the other mineral element contents, while Cu content had significantly negative associations with the K and Mg contents of rice. The relationships between mineral element contents and cooking quality traits showed that gel consistency (GC) was significantly correlated with K, Cu, and Mn contents of rice. Amylose content (AC) was significantly associated with K, Na, Mg, Cu, and Mn contents. The alkali spreading value (ASV) had closely positive relationships with Ca, Mg, and Mn contents. In addition, 8 mineral element contents had obvious correlations with different amino acid contents. Mg, Ca, and Zn contents were significantly correlated with most of the 17 amino acid contents, but Na content did not correlate with amino acid contents except aspartic acid of rice. Furthermore, significant associations were found between protein content and Na, Mg, Zn, Cu, or Mn content. Six principal components were extracted to explain 84.50% of the total variances and contained the information provided by the original 29 variables according to the principal component analysis. 相似文献
922.
An index of the buffering capacity for phosphate of a group of soils was obtained by measuring adsorption of phosphate from dilute solutions of calcium chloride. The effect of buffering capacity on the amount of phosphate initially displaced by solutions of sodium bicarbonate and on the amount of secondary adsorption from bicarbonate was then studied. These two effects were separated using a regression procedure in which the soil: solution ratio was the independent variable.As buffering capacity increased the amount of phosphorus initially displaced decreased and the amount of secondary adsorption increased. Both these changes resulted in a decrease in the amount of phosphate in the extract. The effect of buffering capacity was greater with the Olsen method (soil : solution ratio 1 : 20; 30 min) than with the Colwell method (soil : solution ratio 1 : 100; 16 h). The relation between phosphorus extracted and buffering capacity was of a similar shape to that between effectiveness of fertilizer and buffering capacity. However, the first relation depends on the conditions of extraction and the second on the kind of plant grown and on the conditions of growth. Hence the two relations do not necessarily coincide.The effect of buffering capacity on the proportion of added phosphate initially displaced from the soil became more marked as the period of incubation prior to extraction was increased. Bicarbonate soil tests would therefore indicate that, on soils of low buffering capacity, the decrease with time in availability of applied phosphate would be smaller than on soils of high buffering capacity. This effect differs from that observed with plants. 相似文献
923.
J.?M.?PitaEmail author J.?B.?Martínez-Laborde E.?Zambrana C.?de la?Cuadra 《Genetic Resources and Crop Evolution》2005,52(5):513-517
The germinability of the Vicia sativa L. seed samples in the base collection at the Centro de Recursos Fitogenéticos (Spain) was controlled in 1986 and 1996. The
mean germination of the collection, assessed by One-Sample T Test, was higher than 85%, suggesting its viability was properly maintained along the period. However, changes in germination
along the same period assessed by Paired-Samples T Test showed a slight decrease in its global germinability. More data on the viability of stored seeds worldwide – including
communication of unpublished data – are needed. Viability assays should be performed according to standard, internationally
coordinated protocols and statistical analysis, within an adequate documentation system that assures the integrity of accession
information. 相似文献
924.
The use of atropine to control heart rate responses during detomidine sedation in horses 总被引:2,自引:0,他引:2
Detomidine is a sedative-analgesic which has a pharmacological profile similar to xylazine. There is evidence that the sedative effects are mediated through alpha-2 adrenoceptors.Cardiopulmonary responses were determined using detomidine as the principal agent and as a preanesthetic prior to the induction of general anesthesia. Compatibility with guaifenesin, sodium thia-mylal and halothane were determined.As in the case of xylazine, detomidine produces a slowing of heart rates. This was found to be either sinus bradycardia or heart block. There may be a corresponding increase in systolic blood pressures. The respiratory pattern is altered through the arterial blood gases and pH data supported evidence of adequate ventilation. The heart rate response to detomidine without anticholinergic treatment was transient and related to he duration of drug action.Atropine sulfate, 0.02 mg/kg i.v. was effective in preventing or treating bradycardia or heart block from detomidine. Heart rates also increased during the administration of guaifenesin and sodium thia-mylal when given 50 min poisit-detomidine. 相似文献
925.
926.
J. H. Heckman H. G. Zuckerman C. H. Metzger W. B. Ward John S. Gardner Frank W. Hussey Ralph W. Donaldson A. G. Tolaas K. H. Fernow E. V. Hardenburg W. G. Been Robert Schmidt E. M. Gillig E. B. Tussing K. W. Lauer K. H. Klages Brooks D. Drain H. L. Bailey J. G. Milward 《American Journal of Potato Research》1935,12(7):196-204
927.
K. TÖRNEKE C. INGVAST LARSSON L.- E. APPELGREN 《Journal of veterinary pharmacology and therapeutics》1997,20(3):216-219
Strips of tracheal smooth muscle from 12 horses were contracted by carbachol in tissue baths under isometric conditions. This contraction (≅50% of maximum: EC50 ) was relaxed completely with adrenoceptor drugs. The only exception was clenbuterol, where the degree of relaxation was ≅90%. In all horses the EC50 -value for isoprenaline (mean 1.6 × 10−8 M) was less than that for adrenaline (mean 9.6 × 10− 8 M) and noradrenaline (mean 1. 8 × 10- 6 M). The potency ratio was 1 < 6 < 110 which indicates that the β2 -subtype dominates among the β-adrenoceptors of equine airways. All preparations were also very sensitive to the specific and potent β2 -receptor agonists clenbuterol (mean 5.7 × 10− 9 M) and procaterol (mean 3.6 × 10−10 M). No differences in EC50 -values due to age, sex and breed were observed in this material. The standard deviation of the mean EC50 -values seems to be larger for the specific β2 -adrenoceptor agonists than for the unspecific. A reason for this could be differences in the pattern of the β-adrenoceptor population. 相似文献
928.
Sironi G Manarolla G Pisoni G Recordati C Rampin T 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2006,53(7):347-349
The study describes a highly productive myotropic avian leukosis virus infection (ALV) in a 3-month-old female chicken. At necropsy, ascites, hepatic fibrosis and cardiomegaly were seen. Histologically, the most striking lesion was the presence of cytoplasmic basophilic inclusions in myocardial fibers. Immunostaining for ALV group specific antigen p27 revealed a diffuse presence of virus antigen in cardiac myofibers, in smooth muscle fibers of most of the organs, and in rare, pancreatic and ovarian theca cells. Ultrastructurally, myocardial inclusions consisted of clusters of 50-60 nm round particles with interspersed ribosome-like granules. Numerous C-type particles were found in intercellular spaces of ALV p27 positive tissues. PCR analyses revealed the presence of both ALV-E and ALV-J related sequences. In chicken genome, ALV-E is usually present as endogenous provirus therefore, the pathological findings observed in this case are considered to be related with the ALV-J infection. The results of this report further confirm that ALV-J may be responsible for highly productive myotropic infections. 相似文献
929.
M. Ricárdez-Salinas M.V. Huitrón-Ramírez J.C. Tello-Marquina F. Camacho-Ferre 《Scientia Horticulturae》2010
One of the major challenges of melon (Cucumis melo L.) yield is the decrease of fruit yield and quality caused by soil diseases. Soil disinfection with methyl bromide (MB) has been used to prevent soil-borne diseases damage; however, use of MB is being restricted because this substance damages the ozone layer. Searching for new MB alternatives, field experiments were carried out in open fields in soils infested with Fusarium oxysporum f. sp. melonis, Olpidium bornovanus, and Melon Necrotic Spot Virus (MNSV) in Colima, Mexico, where melons had only been grown previously using soil fumigation with MB. Yield and quality of melon cultivar Cruiser F1 (Harris Moran seed company) grafted on two rootstocks of Cucurbita maxima Duchesne × Cucurbita moschata Duchesne (“RS841”; Séminis seed company and “Shintosa Camelforce”; Nunhens seed company) were evaluated during two consecutive years. Each experiment had five treatments, two of which with non-grafted plants at a density of 18,519 plants/ha, with and without MB fumigation. The other three treatments consisted of grafted plants in non-fumigated soil with plant densities of 14,815, 11,111, and 9260 plants/ha. The use of melon grafted on “RS841” and “Shintosa Camelforce” rootstocks significantly increased the average fruit weight and the total yield of melons in soil without the need for MB. Grafting may be considered an alternative to MB fumigation. With the use of grafted melon plants, planting density may be reduced by 60%, obtaining higher yields than those obtained from non-grafted plants grown on fumigated land. Fruits harvested from grafted plants had equal firmness than those harvested from non-grafted plants, without affecting the content of soluble solids. 相似文献
930.
Restriction endonuclease fingerprints of infectious laryngotracheitis virus (ILTV) DNA from 13 Pennsylvania field isolates, embryo-propagated and tissue-culture-propagated vaccine strains, and three reference strains were compared. These comparisons were made to evaluate the possible contribution of mutation of ILTV vaccine strains to recent outbreaks of infectious laryngotracheitis (ILT) in Pennsylvania. Six different restriction enzymes were used to generate the fingerprints. Differences in DNA banding patterns were revealed between the currently used ILTV vaccine strains and six of the 13 field isolates. Even greater DNA banding pattern differences were found between the older ILTV reference strains and the vaccine strains. The ILTV DNA fingerprints generated in the present study suggest that at least five different strains of ILTV have contributed to the outbreaks of ILT that have occurred since 1987 in Pennsylvania. 相似文献