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中国锦紫苏类病毒的检测及其分子生物学特征研究 总被引：4，自引：0，他引：4
从无明显症状表现的11株锦紫苏叶片中抽提低分子量的RNA,经Return-PAGE、RT-PCR和Dot-blot hybridization检测,结果表明11株锦紫苏全部带有锦紫苏类病毒(Coleus blumei viroid,CBVd)。将部分PCR产物克隆到pGEM-3Zf(+)载体上并进行DNA序列测定。序列分析结果,所克隆的序列(GenBank登录号分别为DQ178395、DQ178396、DQ178397、DQ178398和DQ178399)与GenBank中报道的锦紫苏类病毒1号(CBVd-1)序列同源性为85.23%~99.20%。从市场上购买的锦紫苏种子经Return-PAGE和RT-PCR检测不携带锦紫苏类病毒。这是中国发生的锦紫苏类病毒的首次报道。 相似文献
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Eight samples of Ando soil A1 and buried A1 horizons of different ages were fractionated into clay-, silt-, and sand-size separates, and the yields and carbon contents of these separates were determined. The clay-size separates were subjected to two series of successive extractions, 1) 0.1 M Na4 P2 O7/2% Na2 CO3/0.5 M NaOH and 2) dithionite-citrate/2% Na2 CO3/0.5 M NaOH; and to difference infra-red spectroscopy for identification of the extracted constituents. The result indicated that humus evolves from forms with a very low complexing ability for Al and Fe into forms that complex Al and Fe in the A1 horizon, and that humus further interacts with allophane-like constituents, allophane and imogolite in the buried A1 horizon. These reactions between humus and inorganic constituents result in formation of silt- and sand-size aggregates which are stable to sonic wave treatment, but are broken down into finer particles upon boiling with H2 O2. 相似文献
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THE CATEGORIES OF ALUMINIUM- AND IRON-HUMUS COMPLEXES IN ANDO SOILS DETERMINED BY SELECTIVE DISSOLUTION 总被引：2，自引：0，他引：2
Thirty-three samples of Ando soils were extracted by sodium pyrophosphate (O.IM; pH 10) and by dithionite-citrate. The Al, Fe, and C contents of these two extracts offer a means of differentiating the status of humus in relation to Al and Fe in the different horizons. The humus that forms at first in the Al horizon has a very low complexing ability for Al and Fe and little is dissolved by pyrophosphate. The humus evolves with time or pedogenesis into forms that complex Al and Fe released from volcanic ash by weathering, and which are dissolved by pyrophosphate. In the old horizons, the humus further reacts with additional Al and Fe, some of which may be present as hydrous oxides or allophane-like constituents, allophane and imogolite. This reaction probably makes the humus less soluble in pyrophosphate. 相似文献
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Changes in fertility of rainbow trout eggs retained in coelom 总被引：1，自引：0，他引：1
TERUO AZUMA HIROMI OHTA SABURO ODA KOJI MUTO TAKASHI YADA TATSUYA UNUMA 《Fisheries Science》2003,69(1):131-136
ABSTRACT: Effects of prolonged retention time of ovulated eggs in the parental coelom on fertilization success were studied in rainbow trout Oncorhynchus mykiss using cryopreserved sperm with a uniform fertilizing ability. Proportions of successful fertilization, eyed eggs and hatched alevins were examined at different time periods up to a retention time of 14 days beyond the ordinary stripping time, and were compared with eggs incubated in artificial coelomic fluids (ACF). Eggs that were retained longer in the coelom showed gradual decreases in all the proportions of successful fertilization, eyed eggs and hatched alevins. The progress of cleavage after fertilization slowed with prolonged retention times. Eggs incubated in ACF lost their fertilizing ability much sooner than those retained in the coelom. The hatching rate of eggs retained for 2 weeks in coelom was 36%, while it was 1% in those eggs incubated for 4 days in ACF. Thus, eggs retained in the coelom showed higher fertilization success than those incubated in ACF. 相似文献
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