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141.
Fruit abscission in water dropwort (Oenanthe stolonifera DC.) was investigated by measuring fruit removal force (FRF) affected by fruit ages and plant hormones. FRF decreased rapidly 30 days after anthesis (DAA). Ethylene evolution increased rapidly at 35 DAA and ABA concentration increased gradually after 20 DAA. ACC and ethephon decreased the FRF of fruit explants and the promoting effect of ACC was delayed by silver thiosulphate and cycloheximide, but not by norbornadiene and actinomycin D. ABA enhanced fruit abscission without increasing ethylene evolution. However, the observation that CoCl2 delayed abscission induced by ABA indicates possible involvement of ethylene in the ABA effect. Treatment with NAA, fenoprop and IAA had no effect on 30 DAA fruit explants, but IAA delayed abscission of 25 DAA explants. This suggests that the effect of auxins may differ with fruit age when used as control agents. 相似文献
142.
143.
Kwangho Choi Chung Il Lee Kwangseok Hwang Sang-Woo Kim Jong-Hwa Park Yeong Gong 《Fisheries Research》2008,91(2-3):281-290
Data on squid catches of Korean and Japan, water temperatures at depth of 100 m, and night-visible images of fishing boats collected in the East (Japan) Sea from 1970 to 1999 were analyzed to examine the distribution and migration of the Japanese common squid, Todarodes pacificus, in the southwestern part of the East (Japan) Sea. The main fishing grounds detected from squid catch in each grid (0.5° latitude × 0.5° longitude) by Korean squid fishery and night-visible images provided by the Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) were situated in the southwestern part of the East (Japan) Sea. The distribution and migration route was illustrated from squid catch in each grid and DMSP OLS image. In years of high catches, the fishing grounds were situated mainly between Ulleung Island and the eastern coastal waters of Korea, while in years of low catches they were situated between Ulleung Island and the Yamato Bank in the central East (Japan) Sea. The center of fishing activity began moving northward from around the Korea/Tsushima strait to the northern boundary of the Tsushima Warm Current in March, reaching into the Yamato Bank in September, and then returning to the strait by February. The northward and southward migration routes differed; the northward migration route occurred closer to the mainland coast of Korea than the southward migration route did. This work suggests T. pacificus begin their northward migration almost 2 months earlier than previously suggested. 相似文献
144.
Changes in the concentrations of B, Ca, Fe, K, Mg, Mn, Na, P, S, Sr and Zn in the liquid phase in sheep rumen were determined to obtain information on their rate of disappearance from the soluble pool after feeding. Sheep were fed alfalfa (Medicago sativa) hay hourly. The concentration of infused Cr(III)-EDTA into the rumen (over a period of 4 d) was used to establish steady-state conditions, after which feeding was stopped and the rapidly changing elemental concentrations in 30,000 x g ruminal supernatant fluid were determined by plasma emission spectrometry. The concentrations of all elements, apart from Fe, Na and P, decreased in a first-order manner over 5 h after feeding. For one sheep, these concentrations (microM) were: B, 199 to 126; Cr, 184 to 111; Ca, 4,150 to 1,130; K, 51,000 to 28,800; Mn, 11 to 4.2; Mg, 4,190 to 1,810 and Zn, 14 to 7.8. For S, first-order decay was observed over only the 0- to 2-h period (2230 microM to 865 microM). Phosphorus increased from 10.4 to 13.1 mM over the 5-h period, whereas Na remained constant (85 mM); this was attributed to saliva input. Mean half-lives for B (8.8 h), K (7.5 h) and Zn (5.3 h) were similar to those of Cr (6.3 +/- .3 h), the water flow marker. Mean half-lives of Ca (2.6 h), Mg (4.0 h), Mn (3.3 h), Sr (3.3 h) and S (1.8 h) were shorter (P less than .01) than that of the Cr marker.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
145.
A L Bertone G L Cockerell R E Lee T S Stashak 《American journal of veterinary research》1990,51(9):1471-1475
Light microscopy, morphometry, and scanning electron microscopy were used to examine the mucosal morphologic features of 7 intestinal specimens (3 from the small intestine; 4 from the large intestine) from each of 8 horses 1 year after sham operation (group 1; n = 3) or extensive large-colon resection (group 2; n = 5). Qualitative light microscopic examination did not reveal differences between groups, but morphometry revealed significantly (P less than 0.05) greater intercrypt area and distance in horses with colon resection and this was most pronounced in the cecum and remaining right ventral and dorsal colon. Crypt area and depth were similar for horses with colon resection and sham operation (P greater than 0.05). Qualitative evaluation of the scanning electron micrographs revealed more prominent crypt orifices in the large intestine of horses with colon resection. The larger intercrypt distance in the colon of horses with resection was not an obvious feature of the qualitative evaluation of the surface with scanning electron microscopy. Small intestinal morphologic features were variable and significant differences were not detected between horses with sham operation and colon resection. Horses adapted to extensive large-colon resection within 1 year by increasing the absorptive (intercrypt) surface area of the remaining large intestine. 相似文献
146.
147.
148.
Fu-Hui Wu Shu-Chen Shen Lan-Ying Lee Shu-Hong Lee Ming-Tsar Chan Choun-Sea Lin 《Plant methods》2009,5(1):16-10
Background
Protoplasts isolated from leaves are useful materials in plant research. One application, the transient expression of recombinant genes using Arabidopsis mesophyll protoplasts (TEAMP), is currently commonly used for studies of subcellular protein localization, promoter activity, and in vivo protein-protein interactions. This method requires cutting leaves into very thin slivers to collect mesophyll cell protoplasts, a procedure that often causes cell damage, may yield only a few good protoplasts, and is time consuming. In addition, this protoplast isolation method normally requires a large number of leaves derived from plants grown specifically under low-light conditions, which may be a concern when material availability is limited such as with mutant plants, or in large scale experiments. 相似文献149.
W M Pedersoli W R Ravis H S Lee L M Krista J S Spano 《American journal of veterinary research》1990,51(11):1751-1755
A single dose of digoxin was injected, IV, into 5 mature male turkeys (0.066 mg/kg of body weight), 8 male ducks (0.066 mg/kg), and 6 roosters (0.33 mg/kg). Twenty-three serial venous blood samples were collected before (baseline) and after the administration of digoxin to turkeys, ducks, and roosters. Plasma concentrations of digoxin were determined in duplicate by a radioimmunoassay that was validated for avian species. The plasma concentrations were best fitted by a 3 (turkeys, ducks)- and 2 (roosters)-compartment open model, with first-order elimination from the central compartment. Significant (P less than 0.05) kinetic differences were determined among species. Mean half-life (t1/2) for ducks, roosters, and turkeys were 8.30 +/- 2.70 (mean +/- SD), 6.67 +/- 3.50, and 23.7 +/- 4.8 hours, respectively. The volume of distribution at steady state (Vss) was 14.7 +/- 2.9, 3.13 +/- 0.49, and 2.27 +/- 0.36 L/kg, and total body clearance (CL) of drug was 1.54 +/- 0.43, 0.461 +/- 0.187, and 0.136 +/- 0.022 L/h/kg for ducks, roosters, and turkeys, respectively. The mean residence time was 10.3 +/- 3.9, 8.37 +/- 4.97, and 16.8 +/- 2.2 hours, respectively. Volume of distribution at steady state and CL in ducks were several fold higher than that in turkeys. The terminal half-life of digoxin determined for ducks and roosters in this study was considerably shorter than those previously reported for several mammalian species. 相似文献
150.
Kyung-Ho Ma Jae-Gyun Kwag Weiguo Zhao Anupam Dixit Gi-An Lee Haeng-Hoon Kim Ill-Min Chung Nam-Soo Kim Jae-Sun Lee Jae-Jun Ji Tae-San Kim Yong-Jin Park 《Scientia Horticulturae》2009,122(3):355-361
Here we characterized eight novel polymorphic SSR markers, developed from an enriched genomic library of garlic (Allium sativum L.). These SSRs produced a total of 64 alleles across 90 garlic accessions, with an average of 8 alleles per locus. Values for observed (HO) and expected (HE) heterozygosity ranged from 0.16 to 0.77 (mean = 0.44) and from 0.22 to 0.86 (mean = 0.65), respectively. Six loci deviated significantly (P < 0.05) from Hardy–Weinberg equilibrium (HWE). The averages of gene diversity and PIC values were 0.65 and 0.62, respectively. The mean genetic similarity coefficient was 0.4380, indicating that among garlic accessions existed wide genetic variation. Based on 64 alleles obtained by 8 SSRs, a phenogram was constructed to understand the relationships among the 90 accessions. These newly developed SSRs should prove very useful tools for genotypes identification, assessment of genetic diversity and population structure in garlic. 相似文献