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1.
Polyaryl esters of moderate molecular weights were prepared by the direct polycondensation reaction of hydroxybenzoic acids and its derivatives with hexachlorocyclotriphosphatriazene (also known as phosphonitrilic chloride trimer, PNC) as a condensing agent in pyridine. Copolymerization of p-hydroxybenzoic acid with several hydroxybenzic acid derivatives was carried out to improve the processability of the polymer of p-hydroxybenzoic acid, which yields fusible and soluble copolymers of high inherent viscosities. Polymer solubility and thermal behavior were examined.  相似文献   
2.
The pure cis- and trans-isomers of ethyl N-(2-pyridinyl)aminomethylenecyanoacetates were obtained and their structure and their interconvertibility is diseussed. 4H-Pyrido[1,2-a]pyrimidin-4-one-3-carboxylic acids were synthesized by treatment of both cis- and trans-isomers with hydrochloric acid.  相似文献   
3.
Synthesis and properties of hitherto unknown thiazolo[5,4-d]pyrimidine 1-oxides are described. For example, the reaction of 6-chloro-1,3-dimethyl-5-nitrouracil (I) with methyl thioglycolate in the presence of excess triethylamine afforded 2-methoxycarbonyl-4,6-dimethylthiazolo[5,4-d]pyrimidine-5,7-(4H,6H)dione 1-oxide (IIIa), which is a versatile intermediate for the preparation of various thiazolo[5,4-d]pyrimidine derivatives.  相似文献   
4.
The reaction of 6-arylidenehydrazino-1,3-dimethyluracils with thionyl chloride in benzene afforded purine, thiazolo[4,5-d]pyrimidine, pyrimido[4,5-e][1,3,4]thiadiazine, pyrazolo[3,4-d]pyrimidine, and [1,2,3]thiadiazolo[4,5-d]pyrimidine derivatives, while the treatment of 6-(benzylidene-1′-methylhydrazino)-1,3-dimethyluracil with thionyl chloride in benzene gave 4-methylpyrimido[4,5-e][1,3,4]thiadiazine and 1-methylpyrazolo-[3,4-d]pyrimidine derivatives. Plausible mechanisms for the formation of these fused pyrimidines are also described.  相似文献   
5.
Sandwich immunoassay was conducted on a thin gold film set in a surface plasmon resonance (SPR) cell. Monochronal antibody (anti-IgG) was immobilized onto the gold film via 4,4′-dithiodibutyric acid (DDA) and avidin-biotin bonding. Next, IgG sample and alkaline phosphatase-conjugated anti-IgG (ALP anti-IgG) were introduced into the cell successively. Finally, p-aminophenyl phosphate (PAPP) was injected as an enzyme substrate, and the produced p-aminophenol (PAP) was electrochemically measured. Flow did not need to be stopped for incubation for the enzyme reaction, because of the thinness of the cell. In these processes, all the antigen-antibody reactions took place on the gold film. Therefore, the immobilization was performed quickly, and each process could be confirmed by SPR signal. This system had the advantage that the middle of the complicated process could be monitored. For example, the amount of antibody immobilized, which affected on the final electrochemical signal, could be confirmed in the course of immobilization. It was also convenient to investigate process conditions, such as removal of used antigens and labeled antibodies. Good correlation was obtained between the electrochemical current and the SPR signals due to the adsorption of IgG and ALP anti-IgG, and the sensitivity of the electrochemical measurement was much higher than the SPR’s.  相似文献   
6.
Uptake of alkane (C5-C9) and alcohol (C4-C7) solutes by both strong acid cation exchange resins and strong base anion exchange resins in aqueous medium has been studied. The amount of solute taken up by resins is directly proportional to the solute concentration equilibrium with resins. Hydrophobic interaction between the solute and the resin matrix appears to play an important role in the uptake phenomenon.  相似文献   
7.
Five SNPs in the human DNase II gene have been reported to be associated with rheumatoid arthritis (RA). Genotype and haplotype analysis of 14 SNPs, nine SNPs of which reported in the NCBI dbSNP database in addition to these five SNPs, was performed in healthy subjects. The enzymatic activities of the amino acid substituted DNase II corresponding to each SNP and serum DNase II in healthy Japanese, and promoter activities derived from each haplotype of the RA‐related SNPs were measured. Significant correlations between genotype in each RA‐related SNP and enzymatic activity levels were found; alleles associated with RA exhibited a reduction in serum DNase II activity. Furthermore, the promoter activities of each reporter construct corresponding to predominant haplotypes in three SNPs in the promoter region of the gene exhibited significant correlation with levels of serum DNase II activity. These findings indicate these three SNPs could alter the promoter activity of DNASE2, leading to a decline in DNase II activity in the serum through gene expression. Since the three SNPs in the promoter region of the DNase II gene could affect in vivo DNase II activity through reduction of the promoter activity, it is feasible to identify these SNPs susceptible to RA.  相似文献   
8.
Reaction of 5-arylazo-6-arylidenehydrazino-1,3-dimethyluracils (II), prepared by the treatment of 6-aryl-idenehydrazino-1,3-dimethyluracils (I) with diazotized arylamines, with dimethylformamide dimethylacetal resulted in the formation of pyrimido[5,4-e]-as-triazine (V) system, while the thermolysis of II resulted in the formation of purine (X), v-triazolo[4,5-d]pyrimidine (XII), and pyrazolo[3,4-d]pyrimidine (XIV, XIX) systems in lieu of the expected V. Reasonable mechanisms have been proposed for the formation of the various ring systems in these reactions.  相似文献   
9.
Deoxyribonucleases (DNases) have been suggested to be implicated in the pathophysiology of autoimmune diseases. In the DNASE1L3 gene encoding human DNase I‐like 3 (DNase 1L3), a member of the DNase I family, only two non‐synonymous (R178 H and R206C) single nucleotide polymorphisms (SNPs) have been examined [Ueki et al., Clin. Chim. Acta 2009, 407, 20–24]. Three other non‐synonymous (G82R, K96N, and I243M) and four synonymous (S17S, T84T, R92R, and A181A) SNPs, in addition to R206C and R178H, have been identified in DNASE1L3. We investigated the distribution of all these SNPs in exons of the gene in eight Asian, three African, and three Caucasian populations worldwide using newly devised genotyping methods. SNP T84T showed polymorphism in all the populations, and R92R was polymorphic in the three African and three Caucasian populations; R206C was distributed only in Caucasian populations. In contrast, no minor allele was found in five SNPs (S17S, G82R, K96N, A181A, and I243M) in DNASE1L3. Generally, the DNase 1L3 gene shows relatively low genetic diversity with regard to exonic SNPs. When the effect of amino acid/nucleotide substitutions resulting from the SNPs on DNase 1L3 activity was examined, none of the synonymous SNPs had any effect on the DNase 1L3 activity, whereas among non‐synonymous SNPs, SNP G82R diminished the activity of the enzyme, being similar to R206C. These findings permit us to assume that, although only R206 exhibits polymorphisms in a Caucasian‐specific manner, at least SNPs G82R and R206C in DNASE1L3 might be potential risk factors for autoimmune disease.  相似文献   
10.
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