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601.
作物抗寒剂筛选试验   总被引:2,自引:0,他引:2  
用筛选出的A,8两种抗寒药剂处理水稻、玉米、黄瓜种子和水稻幼苗,结果表明,A剂1000倍液的抗寒效果与进口产品脱落酸(ABA)10-4ug/mL处理的效果相当,比抗寒剂(中国科学院植物所)100倍液要好.供试水稻品种89早229和91-264浸种处理,其成苗率比对照分别增加11.7%和78.2%;喷雾处理分别增加83%和81.3%;灌根处理分别增加86%和71.7%.浸种处理黄糯-玉米种子受冻指数减少92.2%,浸种处理黄瓜种子受冻指数减少72.1%.  相似文献   
602.
The mineral composition of taro ( Colocasia esculenta (L.) Schott) was analyzed to develop a method to distinguish taro produced in Japan and China. The concentrations of 15 elements (Al, Ca, Cl, Mg, Mn, Br, Co, Cr, Cs, Fe, K, Na, Rb, Sc, Zn) were assayed using instrumental neutron activation analysis. The concentrations of NO(3)(-), SO(4)(2-), H(2)PO(4)(-), Cl(-), malate, and oxalate were measured by ion chromatography. The mean concentrations of H(2)PO(4)(-), Co, Cr, and Na significantly differed (P < 0.01) between taro grown in Japan and that grown in China. Discriminant analysis was performed to identify the most efficient combination of elements and compounds to discriminate the taro geographic origin. The highest percentage of correct classification was achieved with a two-variable model including H(2)PO(4)(-) and Co (100% for Japanese, 93.75% for Chinese). Principal component analysis and cluster analysis using all of the assayed elements and compounds were also conducted to determine which elements significantly accounted for the variation of the taro mineral composition. We report on the potential of H(2)PO(4)(-) and Co concentrations to differentiate taro grown in China and Japan and discuss the sources of variability in the taro mineral composition of our samples.  相似文献   
603.
Paddy and Water Environment - We characterized 63 fields sampled based on farmers’ perception of production risks within each commune (referred as either safe or at-risk fields), from the 3...  相似文献   
604.
Potassium bromide overdose (bromism) in the management of canine epilepsy has been known. However, a protocol to reduce bromide concentrations rapidly has not been previously established. The effects of three infusion fluids with different chloride contents on the steady‐state serum concentrations of bromide in beagles were determined. After stabilization of the serum bromide concentrations, seven dogs were infused with saline (Na+ 154 mmol/L; Cl? 154 mmol/L), lactated Ringer's (Na+ 131 mmol/L; Cl? 110 mmol/L), or maintenance solutions (Na+ 35 mmol/L; Cl? 35 mmol/L) at a rate of 2 or 10 ml kg?1 hr?1 for 5 hr. Serum and urine were collected hourly, and the bromide concentrations were measured. When saline and lactated Ringer's solutions were infused at a rate of 10 ml kg?1 hr?1 for 5 hr, serum bromide concentrations were decreased by 14.24% and urine bromide concentrations by 17.63%, respectively. Of all compositions of infusion fluids, only sodium and chloride contents were associated with the decreased serum concentrations and the increased renal clearance of bromide. In summary, saline and lactated Ringer's solutions reduced serum bromide concentrations in a sodium chloride‐dependent manner in dogs were found when infused at 10 ml kg?1 hr?1 for 5 hr.  相似文献   
605.
The natural occurrence of Japanese cedar (Cryptomeria japonica) pollinosis has been reported in dogs with atopic dermatitis. However, the reactivity to Japanese cypress (Chamaecyparis obtusa) pollen allergens in these dogs has not been reported. The present study was designed to investigate the reactivity to Japanese cypress pollen allergens in dogs sensitized to Japanese cedar pollen allergens. In 19 dogs with specific IgE to C. japonica pollen allergen, we measured the specific IgE to C. obtusa pollen allergen and examined the reactivity to the allergen by intradermal test. Of the 19 dogs, 18 had specific IgE to crude and purified major allergens (Cha o 1) of C. obtusa pollen. Most of the dogs showed a positive reaction to C. obtusa pollen allergens in the intradermal test. Allergenic cross-reactivity between Cha o 1 and Cry j 1 (a major allergen in C. japonica pollen) was observed by the ELISA inhibition method. Dogs sensitized to Japanese cedar pollen allergens demonstrate reactivity to Japanese cypress pollen allergens.  相似文献   
606.
A method for separating n-paraffins from petroleum hydrocarbons in foods was developed. The method consists of 5 initial steps: digestion of sample with alkali, silica gel column chromatography, molecular sieve adsorption, destruction of the sieve with HCl, and oxidation with KMnO4. Recoveries of n-paraffins added to 55 g oyster at a level of 0.36 ppm ranged from 80% for normal pentadecane to 100% for n-paraffins over 18 carbon atoms. This method also facilitated the analysis of iso-paraffins such as pristane (2,6,10,14-tetramethylpentadecane) and phytane (2,6,10,14-tetramethylhexadecane), and other hydrocarbons, which are thought to be good marker compounds for the estimation of petroleum pollution.  相似文献   
607.
608.
To characterize the 22:6 n-3 (docosahexaenoic acid, DHA) levels of the oriental bonito Sarda orientalis, a coastal migratory tuna species, total lipids (TL) of white muscle, dark muscle, liver, pyloric cecum, gonad, and other viscera were separated into lipid classes, the constituents of TL were quantified, and the fatty acid composition of TL, triacylglycerols (TAG), phosphatidylethanolamine, and phosphatidylcholine was analyzed. The crude lipid contents of muscle and other organs were 0.8–3.2% and 2.3–9.1%, respectively. DHA was found in TL of various organs at levels ranging from 19.2% to 27.6% in muscle and 16.3% to 28.5% in other organs. The levels of DHA in muscle TAG (8.2–16.0%) were lower than or comparable to those in visceral TAG (6.9–24.0%). These findings did not coincide with those observed in active-migratory tuna species, which accumulate DHA in their muscle TAG during migration. These findings suggest that the DHA distribution of S. orientalis is different from that observed in active-migratory tuna species, and that the differences may be due to migration type of the fish.  相似文献   
609.
To apply otolith microstructure to examination of age and growth of juvenile chum salmon Oncorhynchus keta inhabiting coastal waters, formation of otolith increments was investigated for juveniles reared in a seawater aquarium and in net pens. In all otoliths examined, a distinctive check was formed at the time of sea entry of the fish. The deposition of otolith increments after the check was daily for rearing both in the aquarium (57 days) and in the net pens (26 days). Check formation associated with sea entry was also observed in otoliths of juvenile salmon collected 1 km off the coast of Shari, Hokkaido, Japan. Transmitted light observation of otoliths of those fish revealed a transition in otolith increment appearance from dark to light. Otolith Sr: Ca ratio remarkably changed from a low to a high level, coinciding with the transition in otolith appearance. It is suggested that the transition was associated with individual sea entry. This study demonstrated that the check and/or transition associated with sea entry are applicable to a benchmark for otolith increment counts of juvenile chum salmon inhabiting coastal waters.  相似文献   
610.
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