• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.313.2-313
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• 1995

No Abstract, See Full Text

• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.345.2-345
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• 1995

No Abstract, See Full Text

• Archives of Pharmacal Research
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• v.7 no.1
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• pp.47-52
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• 1984

Four polymorphic forms (I, II, III and IV) of hydrochlorothiazide have been characterized on the basis of x-ray diffractometry and differential thermal analysis. Form I was obtained by crystallization from N, N-dimethylformamide and Form II was crystallized from hot methanol. Form III was precipitated from sodium hydroxide aqueous solution by treatment with hydrochloric acid and Form IV was crystallized from 50% methanol. The metastable form I was a most stable form among four polymorphs, which was stable more than ten months at room temperature. The thermodynamic parameters such as heat of solution, enthalpy, entropy, free energy difference and transition temperature were determined by the measurement of intrinsic dissolution rate. The transition temperature and the heat of transition between the metastable Form I an Form II were determined to be $299.15^{\circ}$K and 5.03 Kcal/mole, respectively and free energy difference ($\delta$ F) was 302. 13 cal/mole. Diuretic action of these four polymorphic forms was also evaluated by monitoring the difference in urinary excretion of sodium, potassium and magnesium in rats.

• Bulletin of the Korean Chemical Society
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• v.30 no.9
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• pp.2007-2010
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• 2009

Donepezil hydrochloride is a reversible acetylcholinesterase inhibitor that is used in the treatment of Alzheimer’s disease to improve the cognitive performance. It shows different crystalline forms including hydrates. Therefore, it is very important to confirm the polymorphic forms in the formulations of pharmaceutical materials because polymorphs of the same drug often exhibit significant differences in solubility, bioavailability, processability and physical/chemical stability. In this paper, four different forms of donepezil hydrochloride were prepared and characterized using X-ray powder diffraction, Fourier transform infrared, and solid-state nuclear magnetic resonance (NMR) spectroscopy. This study showed that solid-state NMR spectroscopy is a powerful technique for obtaining structural information and the polymorphology of pharmaceutical solids.

• Journal of Life Science
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• v.12 no.1
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• pp.27-32
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• 2002

Enzyme electrophoresis was used to estimate genetic diversity and population structure of maize, Zea mays L. (Graminales) in Korea. In nine populations, fourteen of the 24 loci (58.3 %) showed detectable polymorphism. Genetic diversity (0.205) was higher than average values for species with similar life history traits. Although our data are relatively small and the landraces not direct ancestors of cultivar, apparently the domestication process has eroded the levels of genetic variation of maize. The recent cultivars were found to have fewer alleles per locus (1.42 vs. 1.56), fewer alleles per polymorphic locus (2.27 vs. 2.33), lower percent polymorphic locus (33.3% vs. 41.7%), and lower diversity (0.159 vs. 0.185) than landraces. These genetic diversity parameters indicated that the cultivar populations were genetically depauperate relative to landlaces. The GST value of nine populations was 0.239. Nearly 76% of the total genetic diversity in Zea mays was apportioned within populations. The indirect estimate of gene new based on mean GST was moderate (Nm=0.80).

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.05a
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• pp.281-282
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• 2002

Out of 20 primers, 6 generated a total of 1,111 major and minor RAPD bands, producing approximately 4.2 average polymorphic bands per primer in shortnecked clam (Ruditapes philippinarum) population from Anmyeondo. The Bandsharing value altered from 0.15 to 0.74, with the average f 0.51, as calculated by bandsharing analysis. The RAPD profiles obtained with DNAs of two populations from Anmyeondo and Seocheon, respectively, were considerably different (0.20 and 0.51, respectively). The varying degrees of difference among populations amy also be of relevance to the restricted hybridization of wild bivalve. Besides gene mapping and breeding applications, PCR-RAPD systems could be very useful for the rapid certification and quality control of seed production and for every projects based on PCR amplification of specific bivalve DNA fragments.

• BMB Reports
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• v.35 no.5
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• pp.465-471
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• 2002

From fruiting bodies of L. edodes strain L-54, single-spore isolates (SSIs) were collected. Two parental types of L-54 were regenerated via monokaryotization. By means of random-amplified polymorphic DNA (RAPD), DNA samples from L-54, its two parental types, and 32 SSIs were amplified with arbitrary primers. Dedikaryotization was demonstrated, and 91 RAPD-based molecular markers were generated. RAPD markers that were segregated at a 1:1 ratio were used to construct a linkage map of L. edodes. This RAPD-linkage map greatly enhanced the mapping of other inheritable and stable markers [such as those that are linked to a phenotype (the mating type), a known gene (priA) and a sequenced DNA fragment (MAT)] with the aid of mating tests, bulked-segregant analysis, and PCR-single-strand conformational polymorphism. These markers comprised a genetic map of L. edodes with 14 linkage groups and a total length of 622.4 cM.

• Journal of Plant Biology
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• v.39 no.3
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• pp.185-188
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• 1996

Randomly amplified polymorphic DNAs were employed to study the genetic variation and gene introgression in potato dihaploids (2n=24) which were generated after interspecific pollination of tetraploid cultivars (2n=4X=48, Solanum tuberosum cv Irish Cobbler, Superior and Dejima) by haploid inducer clones (2n=2X=24, Solanum phureja 1.22, Hes-5 and Hes-6). Genetic variation and DNA marker segregation among dihaploids were observed. Most dihaploids contain S. tuberosum specific RAPD markers but haploid inducer-specific RAPD markers were also found in some dihaploids. Of six different arbitrary 10-mer oligonucletide primers which showed polymorphism betwen tetraploid cultivars and haploid inducers used, three generated amplification products which seemed to be derived from the S. phureja parent. Our results indicate that chromosomes of dihaploids may not be pure S. tuberosum and the dihaploids may not be produced by parthenogenesis.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.1
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• pp.100-103
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• 2003

Higher environmental temperature affects the economic performance of pigs. Heat shock protein 70 has been shown to play an important role in thermoresistance. The purpose of this study was to assess the effect of a single nucleotide polymorphism in the 5'-flanking region of porcine HSP70.2 on growth performance in Taiwanese Duroc. The genotype of this nt 393 polymorphic site could be verified by digestion with Bsa WI restriction enzyme of a PCR product. Pigs with TT and TC genotypes have thinner backfats than those with CC type (p<0.05). The result suggested that the polymorphic Bsa WI site in the 5'flanking region of porcine HSP70.2 may be used as a marker for the early selection of ultrasonic backfat thickness in Duroc pigs.

• YAKHAK HOEJI
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• v.41 no.3
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• pp.321-327
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• 1997

Investigation of polymorphism has become a requirement in the pharmaceutical industry because the physical properties and bioavailabilities of crystalline drugs depend on their polymorphic form. Five polymorphic modifications and one pseudopolymorphic modification of ecphalothin sodium were prepared by recrystallization, and characterized by UV spectrophotometer, DSC, TGA and X-ray crystallography. The solubilities of all modifications were examined by the disslution test. Form 2 and 1 showed higher solubilities than any other crystal forms. The modifications were also investigated for their stability after storage of 2 months at 100%, 76%, 52% and 0% humidity.