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131.
Development and characterization of genomic and expressed SSRs for levant cotton (Gossypium herbaceum L.) 总被引:2,自引:0,他引:2
132.
Dao KL Sawant RR Hendricks JA Ronga V Torchilin VP Hanson RN 《Bioconjugate chemistry》2012,23(4):785-795
As part of our program to develop breast cancer specific therapeutic agents, we have synthesized a conjugate agent that is a conjugate of the steroidal anti-estrogen and the potent cytotoxin doxorubicin. In this effort, we employed a modular assembly approach to prepare a novel 11β-substituted steroidal anti-estrogen functionalized with an azido-tetraethylene glycol moiety, which could be coupled to a complementary doxorubicin benzoyl hydrazone functionalized with a propargyl tetraethylene glycol moiety. Huisgen [3 + 2] cycloaddition chemistry gave the final hybrid that was evaluated for selective uptake and cytotoxicity in ER(+)-MCF-7 and ER(-)-MDA-MB-231 breast cancer cell lines. The results demonstrated that the presence of the anti-estrogenic component in the hybrid compound was critical for selectivity and cytotoxicity in ER(+)-MCF-7 human breast cancer cells as the hybrid was ~70-fold more potent than doxorubicin in inhibition of cell proliferation and promoting cell death. 相似文献
133.
134.
135.
Establishment of a cell-mediated gene transfer system has potential as a new breeding technique for commercially valuable fishes. As an important step toward developing an inter-species chimera, cells from blastula-stage embryos of rosy barb (Puntius conchonius) were transplanted into zebrafish (Danio rerio) blastula-stage embryos to observe the development of the recipient. From the total of 473 transplants obtained only a fraction of 13 chimeras appeared perfectly normal after one month. Over two in normal 13 chimeras showed some characters from the donor cells with scarce pigmentation. This is the first successful inter-species study on zebrafish by using blastula cell transplants from rosy barb both belonging to the same family cyprinidae. 相似文献
136.
A. Pandit S. B. Sawant J. B. Joshi R. A. Perkins S. K. Sikdar 《Biotechnology Techniques》1989,3(2):125-130
Rheological properties have been measured for aqueous solutions of dextran, polyethylene glycol and bovine serum albumin. Mixtures of these materials have also been studied. A rotating concentric cylinder viscometer was used to study the rheological properties of these materials over the temperature range 10 to 40°C. Over the range of concentrations, molecular weights, temperature and shear rates covered in this work, all aqueous solutions exhibited Newtonian behaviour. Correlations have been reported for viscosities of dextran, polyethylene glycol, and bovine serum albumin. The viscosity of mixtures of these materials is not linear with respect to concentration. 相似文献
137.
138.
Patterns of chloroplast DNA (cpDNA) and mitochondrial DNA (mtDNA) variation
were studied in 378 populations of oak trees sampled throughout the
southern half of France. Six cpDNA haplotypes detected in a previous
European survey and three new cpDNA haplotypes were found in this region.
Two mitochondrial polymorphisms detected earlier by restriction analysis of
PCR-amplified fragments alone, or in combination with single-strand
conformation polymorphism (SSCP), were compared with the cpDNA data.
Sequencing revealed the nature of the two mitochondrial mutations: a
single-base substitution and a 4-bp inversion associated with a 22-bp
hairpin secondary structure. The single-base substitution was then analyzed
by allele-specific amplification. Results for the two cytoplasmic genomes
were combined, which allowed the identification of 12 cpDNA-mtDNA
haplotypes. The 4-bp mtDNA inversion has appeared independently in
different cpDNA lineages. Given the peculiar nature of this mtDNA mutation,
we suggest that intramolecular recombination leading to repeated inversions
of the 4-bp sequence (rather than paternal leakage of one of the two
genomes) is responsible for this pattern. Furthermore, the geographic
locations of the unusual cpDNA-mtDNA associations (due to the inversion)
usually do not match the zones of contact between divergent haplotypes. In
addition, in southern France, the groupings of populations based on the
mtDNA substitution were strictly congruent with those based on cpDNA.
Because many populations that are polymorphic for both cpDNA and mtDNA have
remained in contact since postglacial recolonization in this area without
producing any new combination of cytoplasms involving the mitochondrial
substitution, we conclude that paternal leakage is not a significant factor
at this timescale. Such results confirm and expand our earlier conclusions
based on controlled crosses.
相似文献
139.
Spray columns can be used to isolate and purify proteins using the two-phase aqueous extraction technique based on polyethylene glycol (PEG) and dextran. The fractional dispersed phase (PEG) holdup and overall mass transfer coefficients were measured in a 9.7 mm i.d. spray column. We found that the dispersed phase holdup increased with increasing PEG phase velocity. The overall mass transfer coefficients for bovine serum albumin, normalized for the PEG holdup, were found to be independent of the PEG phase velocity. This result was expected, since true mass transfer coefficients do not vary with phase velocity. 相似文献
140.
A. D. Sawant Manal Gabriel Stephanie Stegall Dr. D. G. Ahearn 《Current microbiology》1991,23(6):315-319
The lipophilic yeastsMalassezia furfur andM. pachydermatis show an initial rapid uptake ofl-leucine followed by slower steady-state rates. At least two independent transport systems forl-leucine were present in both species. The high-affinity system forM. furfur had a KT of 0.047 µM with a Jmax of 222 fM/min/106 cells (65 pM/min/mg dry weight), whereas forM. pachydermatis the KT was 0.067 µM with a Jmax of 709 fM/min/106 cells (89 pM/min/dry weight). The low-affinity system forM. furfur had a KT of 646 µM with a Jmax of 1.62 pM/min/106 cells (0.5 nM/min/mg dry weight) and that ofM. pachydermatis had a KT of 3.3 µM with a Jmax of 9.97 pM/min/106 cells (1.3 nM/min/mg dry weight). Both transport systems were energy-dependent. Cells incubated with Tween 80 showedl-leucine uptake via both transport systems. Cells incubated with a combination of glucose (1%) and Tween 80 (0.01%) showed decreased transport rates for the high-affinity system for both species as compared with cells incubated only with glucose. The low-affinity transport system of both species in the presence of glucose plus Tween 80 showed an initial rapid uptake followed by greater efflux than influx ofl-leucine.l-Leucine demonstrated binding to Tween 80, but the major effect of Tween 80 on membrane transport inMalassezia appears to be on the efflux of transported molecules. 相似文献