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991.
Di Zhang Yamin Li Liang Xu Maosheng Cheng Ying Zhou Junlin He 《Nucleosides, nucleotides & nucleic acids》2013,32(10):734-747
Tert-butyldiphenylsilyl (TBDPS) was testified to be an appropriate orthogonal protecting group for novel 7-hydroxyl-functionalized 8-aza-7-deaza-2′-deoxyadenosine analogues. It was stable in partial and complete hydrogenation reactions used for the different linker preparation. The corresponding phosphoramidites and hydroxyl-functionalized oligodeoxynucleotides were synthesized and identified. The thermal effect of the hydroxyl group with different linkers on DNA duplexes was evaluated. It provided a feasible strategy for the preparation of hydroxyl-functionalized DNAs for the nucleic acid research. 相似文献
992.
Yoshihito Ueno Shinji Ishihara Yasutomo Ito Yukio Kitade 《Nucleosides, nucleotides & nucleic acids》2013,32(4-6):475-487
The synthesis and properties of oligonucleotides (ONs) containing 9-(2,3,4-trihydroxybutyl)adenine, A C2 and A C3, are described. The ON containing A C2 involves the 3′ → 4′ and 3′ → 5′ phosphodiester linkages in the strand, whereas that containing A C3 possesses the 3′ → 4′ and 2′ → 5′ phosphodiester linkages. It was found that incorporation of the analogs, A C2 or A C3, into ONs significantly reduces the thermal and thermodynamic stabilities of the ON/DNA duplexes, but does not largely decrease the thermal and thermodynamic stabilities of the ON/RNA duplexes as compared with the case of the ON/DNA duplexes. It was revealed that the base recognition ability of A C2 is greater than that of A C3 in the ON/RNA duplexes. 相似文献
993.
《Plant Ecology & Diversity》2013,6(2-3):105-113
Background: Seed mass is a life history trait that is related to invasiveness. Under limiting conditions, a trade-off is observed whereby an increase in seed mass occurs at the expense of seed numbers; if the above trade-off holds across climatic gradients it can provide an opportunity to assess the fitness/invasive potential of exotic plants.Aims: To examine the variation in the life history traits of Eschscholzia californica populations across climatic gradients and to relate these traits to observed invasiveness.Methods: We examined 19 populations in Chile. For each population we related seed mass, seed number, the slope of trade-off between seed mass and number and plant density with annual precipitation and mean annual temperature.Results: Seed number and the coefficient of variation in seed mass were positively correlated with climatic variables. Trade-off was detected in 26% of the populations and no relationship was detected with climatic gradient. Plant density was negatively associated with precipitation.Conclusions: The results suggest that for E. californica producing seeds with a variety of sizes is an optimal strategy to face geographic heterogeneity and hence to increase its invasiveness. Increased production of seeds at the cool and wet southern limit of the current range of the species does not contribute to an increase in its invasiveness. 相似文献
994.
《Expert review of proteomics》2013,10(4):337-354
Despite intense global efforts, no new clinical and/or viable biomarkers have been established to overcome the limitation of the prostate specific antigen in the early diagnosis and prognosis of prostate cancer (PCa). The current proteomic approaches to PCa biomarker discovery, each have distinct advantages and disadvantages, yet when combined hold real promise in the coming years. One key approach to this effort is the development of non-targeted, depletion-free and quantitative liquid chromatography–ultra high resolution tandem mass spectrometry (LC–MS) pipelines for the systems-wide interrogation of the diverse proteomes encompassed in whole tissue and blood serum or plasma. Derived quantitative proteomes can be decoded for their biomedical relevance with advanced bioinformatics and bibliographic mining to yield promising ‘molecular portraits’ that can gauge prostatic disease at the serological level. Their functional annotation, although potentially useful, is beyond our current level of biological understanding and should not be requisite for their effective use in the clinical monitoring of prostatic disease. 相似文献
995.
《Anthrozo?s》2013,26(1):25-42
AbstractA conceptual model was developed to describe the dynamics of the pet dog population. The model synthesizes existing data collected for a variety of purposes to estimate the size of the various components of the pet dog population in Washington and Iowa during 1991. The total population mortality rate was estimated as 12.4% per year. Animal shelters in Washington and Iowa handled 7.6% and euthanized 4.0% of the dog population in those two states. When these estimates were extrapolated to the entire U.S. dog population, the model predicted that the total annual turnover in owned dogs was 14.7%, or 7.71 million dogs, that 4 million dogs were handled by animal shelters, and that 2.1 million were euthanized. It was also estimated that 79% of all female dogs were spayed, that household breeding could be attributed to less than one-fifth (18.7%) of the female dogs in the reproductive pool, and that the number of owners contributing to total dog population turnover through failure to retain their dog (103,453) was approximately three times the number of owners who allowed their female dogs to be bred (32,513). 相似文献
996.
《Anthrozo?s》2013,26(4):519-533
ABSTRACTStudies in human medicine show that care of chronically ill family members can affect the caregiver's life in several ways and cause “caregiver burden.” Companion animals are offered increasingly advanced veterinary treatments, sometimes involving home care. Owners choosing such treatments could thus face similar challenges when caring for their animals. This qualitative study uncovers impacts on an owner's life, when attending to the care of an aged or chronically ill dog and reflects on the differing roles of caregivers with animal and human patients. Twelve dog owners were selected for in-depth interviews based on the dogs' diagnoses, and the choice of treatments and care expected to affect the owner's life. Interviews were recorded, transcribed, and analyzed qualitatively. The dog owners reported several changes in their lives due to their dog's condition: practicalities like extra care, changes in use of the home, and restrictions relating to work, social life, and finances. These were time-consuming, tough, and annoying, but could often be dealt with through planning and prioritizing. Changes in the human–dog relationship and activities caused sadness and frustration, which in turn led to feelings of guilt, and in some cases created a feeling of loss. Also, concerns about the progress of the dog's condition, it's welfare, and euthanasia brought emotional distress and many doubts. The owners did, however, respond to the changes differently and as a result experienced different effects on their own life. This study confirms that the situations of caregivers with human and animal patients are in some ways similar, yet the study also identifies and reflects on some of the differences. These include the caregiver role and the options of assistance as well as euthanasia. Veterinary staff are urged to inform owners about possible impacts on their lives when considering careconsuming treatments, and to be aware of the need for support during treatment as well as in decisions about euthanasia. 相似文献
997.
《Chronobiology international》2013,30(3):282-284
This study investigates the effect of mild physical activity before bedtime on the sleep pattern and heart rate during the night. Nine healthy subjects underwent a habituation night, a reference night, and a physical induction night. The physical induction night did not alter the sleep pattern. Physical activity before bedtime resulted in higher heart rate variance during slow-wave sleep. The low-frequency/high-frequency component (LF/HF) ratio during slow-wave sleep in the physical induction night was significantly higher than during the reference night. Increased mean heart rate and higher LF/HF ratio are related to decreased parasympathetic dominance. Exercise up to 1?h before bedtime thus seems to modify the quality of sleep. (Author correspondence: Daniel. Berckmans@biw. kuleuven. be) 相似文献
998.
《Journal of liposome research》2013,23(3):250-257
Dopamine delivery to the central nervous system (CNS) undergoes the permeability limitations of the blood-brain barrier (BBB). Condensation of dopamine with neutral amino acids could afford potential prodrugs able to interact with the BBB endogenous transporters and easily enter the brain. To improve the bioavailability of the dopamine prodrug, 2-amino-N-[2-(3,4-dihydroxy-phenyl)-ethyl]-3-phenyl-propionamide (DOPH), it was encapsulated in unilamellar liposomes of dimiristoylphosphatidylcholine (DMPC) and cholesterol. Vesicles were characterized by dynamic light scattering in order to evaluate their dimensions and vesicle stability, by zeta-potential measurements, by means of electronic microscopy after freeze-fracture and differential scanning calorimetry. The influence of vesicle composition on DOPH chemical and enzymatic stability was also evaluated. The formulated liposome suspensions were found to be stable, monodisperse systems with a negative zeta potential. From the obtained results, it is possible to conclude that, in studied samples, DOPH inclusion in liposomes offers the possibility of preventing photodegradation and of enhancing in vitro plasma stability. These studies suggest the potential of these formulations as a method to prevent DOPH chemical degradation and enzymatic metabolism. 相似文献
999.
《Free radical research》2013,47(9):1036-1043
AbstractElectron spin resonance (ESR) oximetry technique was applied for analysis of catalase activity in the present study. Catalase activity was evaluated by measuring oxygen from the reaction between hydrogen peroxide (H2O2) and catalase-positive cells. It was demonstrated that the ESR spectra of spin-label probes, 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPOL), 4-oxo-2,2,6,6-tetramethyl-1-piperidinyloxy (4-oxo-TEMPO) and 4-maleimido-2,2,6,6-tetramethyl-1-piperidinyloxy (4-maleimido-TEMPO) in the presence of H2O2 were broadened with the concentrations of catalase. It was possible to make a calibration curve for catalase activity by peak widths of the spectra of each spin-label probe, which are broadened dependently on catalase concentrations. The broadened ESR spectra were also observed when the catalase-positive micro-organisms or the mammalian cells originally from circulating monocytes/macrophages were mixed with TEMPOL and H2O2. Meanwhile, catalase-negative micro-organisms caused no broadening change of ESR spectra. The present study indicates that it is possible to evaluate directly the catalase activity of various micro-organisms and mammalian cells by using an ESR oximetry technique. 相似文献
1000.
《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):544-550
A novel series of complexes of the type [M(C36H22N6)X]X2, where M = Cr(III), Mn(III), Fe(III); X = Cl?, NO3?, CH3COO?; and (C36H22N6) corresponds to the tetradentate macrocyclic ligand, have been synthesized by condensation of 1,8-diaminonaphthalene and isatin in the presence of trivalent metal salts in methanolic medium. The complexes have been characterized by elemental analysis, conductance and magnetic measurements, and UV/Vis, IR, and mass spectroscopy. On the basis of these studies, a five coordinate square pyramidal geometry for all of these complexes is proposed. All synthesized macrocyclic complexes have been tested for in vitro antimicrobial activities against some pathogenic bacterial strains, viz. Staphylococcus aureus, Bacillus subtilis (Gram-positive), Escherichia coli, Pseudomonas aeruginosa (Gram-negative), and two fungal strains, viz. Aspergillus niger, Aspergillus flavus. The MICs shown by the complexes against these microbial strains have been compared with MICs shown by standard antibiotic ciprofloxacin and the antifungal drug amphotericin-B. 相似文献