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341.
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343.
The synthetic 10-alkyl isoalloxazines have been found to form vesicles in aqueous and binary solvent systems and confirmed by UV-visible, fluorescence,transmission electron microscopy and quasi elastic light scattering experiments. The mean external diameters of vesicles have been calculated for isoalloxazine with different carbon atom chain at position 10 by transmission electron microscopy and quasi elastic laser light scattering. The gel to liquid phase transition of liposomes measured by differential scanning calorimetry shows reproducible endothermic peak which lies well in the range of typical aqueous vesicles. 相似文献
344.
The inflorescence apex is stratified and has a single layered tunica, bracts as well as all the floral organs develop acropetally.
Except for stamens which are initiated with the activity of deeper layers of apex, all other floral appendages are initiated
with the activity of second layer. On the basis of ontogenetic studies the floral organs have been homologised with the leaves.
The adjacent calyx lobes develop and remain closely appressed and do not show post-genital fusion. Corolla tube is formed
due to zonal growth preceeded by joint growth of hump on the abaxial face of stamen primordia and interprimordial region between
petal primordia. Thus no post-genital fusion was observed. The placentae develop concomitantly with carpellary wall. 相似文献
345.
The development and rapid spread of chloroquine resistance (CQR) in
Plasmodium falciparum have triggered the identification of
several genetic target(s) in the P. falciparum genome. In
particular, mutations in the Pfcrt gene, specifically, K76T and
mutations in three other amino acids in the region adjoining K76 (residues 72, 74, 75
and 76), are considered to be highly related to CQR. These various mutations form
several different haplotypes and Pfcrt gene polymorphisms and the
global distribution of the different CQR- Pfcrt haplotypes in
endemic and non-endemic regions of P. falciparum malaria have been
the subject of extensive study. Despite the fact that the Pfcrt gene
is considered to be the primary CQR gene in P. falciparum , several
studies have suggested that this may not be the case. Furthermore, there is a poor
correlation between the evolutionary implications of the Pfcrt
haplotypes and the inferred migration of CQR P. falciparum based on
CQR epidemiological surveillance data. The present paper aims to clarify the existing
knowledge on the genetic basis of the different CQR- Pfcrt
haplotypes that are prevalent in worldwide populations based on the published
literature and to analyse the data to generate hypotheses on the genetics and
evolution of CQR malaria. 相似文献
346.
Analysis of phylogenetic relationship among five mulberry (Morus) species using molecular markers. 总被引:3,自引:0,他引:3
Species identification in mulberry (Morus) continues to be a point of great debate among scientists despite the number of criteria such as floral characters, wood, and leaf anatomical and biochemical characters used to identify the species within this genus. However, no consensus system of classification has emerged. Hence, an investigation was undertaken with inter-simple sequence repeat (ISSR) and random amplified polymorphic DNA (RAPD) markers to find out the possibility of using these DNA markers to confirm the identity of genotypes in a particular species. Fifteen ISSR and 15 RAPD primers generated 86% and 78% polymorphism, respectively, among 19 mulberry genotypes. The polymorphism among the species varied from 50% to 57% in ISSR markers and 31% to 53% in RAPD markers. Similarity coefficients were higher among the genotypes of M. latifolia, M. bombycis and M. alba. Cluster analyses separated genotypes of M. laevigata and M. indica from those of the other species. Population structure analysis of these species further showed high genetic differentiation coefficients (GST), high heterozygosity between two species (DST), and total heterozygosity among populations (Ht) coupled with considerably low gene flow (Nm) when M. laevigata was paired with other species. Based on these parameters and the result of cluster analysis it is concluded that M. laevigata can be considered as a separate species of mulberry, whereas the other four species may be grouped together and treated as subspecies. 相似文献
347.
Today, the genomic revolution in epidemiology, medicine and population based genetic association studies are results of on-going refocusing efforts toward development of inexpensive and accurate techniques for SNP genotyping. Despite this considerable gain, high throughput and routinely applicable newer SNP detection techniques are still needed. Therefore, aim of this study was to develop and validate a simple, rapid and inexpensive restriction enzyme based method for genotyping of corticotrophin-releasing hormone receptor1 (CRHR1; rs1396862: C>T) gene variant. This polymorphism has been investigated in a variety of psychiatric and association studies of asthma. A total of 250 healthy volunteers were recruited from same ethnicity and their blood DNA samples were employed for genotyping. Primers were designed using Batch primer3 Software. Specificity and functionality of primers were tested with BLAST database and UCSC In-silco PCR respectively. The lake of a PstI recognition site was seen with T allele. The allele frequencies for rs1396862: C>T were 0.88 (C allele) and 0.12 (T allele). We get 100 % concordant genotyping results for sequencing and PCR–RFLP. This newer genotyping approach lowers the cost and increased the speed. It is particularly useful for small basic research studies of complex genetic disorder. 相似文献
348.
349.
S K Srivastava Y C Awasthi A Yoshida E Beutler 《The Journal of biological chemistry》1974,249(7):2043-2048
350.
Yogesh C. Awasthi S. V. Singh H. Ahmad L. W. Wronski S. K. Srivastava E. F. LaBelle 《Molecular and cellular biochemistry》1989,91(1-2):131-136
We have demonstrated the presence of a dinitrophenyl glutathione (Dnp-SG) stimulated ATPase in human erythrocyte membranes. This ATPase mediates the active transport of glutathione — xenobiotic conjugate such as Dnp-SG from erythrocytes into the plasma. It is suggested that this transport system is distinct from the system which actively transports oxidized glutathione from the erythrocytes. 相似文献