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61.
62.
A 0.9 kb cDNA for the foot and mouth disease virus (FMDV) type Asia 1 63/72, cloned in the plasmid pUR222 by dC/dG tailing method, was expressed into a protein which was immunogenic in guinea pigs and cattle. The protein purified to homogeneity was found to be basic and of 38 kDa. A sequence of 879 nucleotides of the inserted cDNA was obtained. The nucleotide sequence was 65% GC-rich and was homologous to the gene for VPI of FMDV types A5, OIK and C3 to the extent of 35-40%. From the nucleotide sequence, a sequence of 293 amino acids was derived which contained 43 arginine, 4 lysine, 7 glutamic acid and 18 aspartic acid residues making the protein highly basic. The molecular weight was calculated to be 31.6 kDa. The 38 kDa protein produced by the cloned cDNA is a fused protein composed of the 293 amino acids; 5 and 55 amino acids of the alpha-complementation protein of the beta-galactosidase at the N and C terminal, respectively, and 5 amino acid coded by the dG/dC tails used for cloning the cDNA.  相似文献   
63.
Obesity, genetic polymorphisms of xenobiotic metabolic pathway, hypermethylation of tumor suppressor genes, and hypomethylation of proapoptotic genes are known to be independent risk factors for breast cancer. The objective of this study is to evaluate the combined effect of these environmental, genetic, and epigenetic risk factors on the susceptibility to breast cancer. PCR–RFLP and multiplex PCR were used for the genetic analysis of six variants of xenobiotic metabolic pathway. Methylation-specific PCR was used for the epigenetic analysis of four genetic loci. Multifactor dimensionality reduction analysis revealed a significant interaction between the body mass index (BMI) and catechol-O-methyl transferase H108L variant alone or in combination with cytochrome P450 (CYP) 1A1m1 variant. Women with “Luminal A” breast cancer phenotype had higher BMI compared to other phenotypes and healthy controls. There was no association between the BMI and tumor grade. The post-menopausal obese women exhibited lower glutathione levels. BMI showed a positive association with the methylation of extracellular superoxide dismutase (r = 0.21, p < 0.05), Ras-association (RalGDS/AF-6) domain family member 1 (RASSF1A) (r = 0.31, p < 0.001), and breast cancer type 1 susceptibility protein (r = 0.19, p < 0.05); and inverse association with methylation of BNIP3 (r = ?0.48, p < 0.0001). To conclude based on these results, obesity increases the breast cancer susceptibility by two possible mechanisms: (i) by interacting with xenobiotic genetic polymorphisms in inducing increased oxidative DNA damage and (ii) by altering the methylome of several tumor suppressor genes.  相似文献   
64.
Understanding the protein structures is crucial, as it is involved in every cellular activity. Several experimental techniques, such as X-Ray crystallography, nuclear magnetic resonance and electron microscopy are available to gain insight about the structure and function of a protein molecule. Gigantic data on protein structural and sequential information is deposited in various repositories regularly which provide us the scope for more theoretical studies. Hydrophobicity always plays a vital role in tertiary structure formation and behavior of a protein molecule. This study focuses on elucidating influence of several physicochemical properties on hydrophobicity of AGC kinase proteins. AGC kinase superfamily is selected due to its tremendous structural and functional variability and sequence data availability. A combined data mining and stochastic approach confirmed that out of 47 parameters, transmembrane tendency influences the target variable most, followed by percent buried residues, GRAVY (Grand Average Hydropathicity) and aliphatic index. Calculating the influence of different physicochemical parameters and their interrelation will aid tremendously in the future of protein science.  相似文献   
65.
Banerjee AK  M S  M N  Murty US 《Bioinformation》2010,4(10):456-462
Biological systems are highly organized and enormously coordinated maintaining greater complexity. The increment of secondary data generation and progress of modern mining techniques provided us an opportunity to discover hidden intra and inter relations among these non linear dataset. This will help in understanding the complex biological phenomenon with greater efficiency. In this paper we report comparative classification of Pyruvate Dehydrogenase protein sequences from bacterial sources based on 28 different physicochemical parameters (such as bulkiness, hydrophobicity, total positively and negatively charged residues, α helices, β strand etc.) and 20 type amino acid compositions. Logistic, MLP (Multi Layer Perceptron), SMO (Sequential Minimal Optimization), RBFN (Radial Basis Function Network) and SL (simple logistic) methods were compared in this study. MLP was found to be the best method with maximum average accuracy of 88.20%. Same dataset was subjected for clustering using 2*2 grid of a two dimensional SOM (Self Organizing Maps). Clustering analysis revealed the proximity of the unannotated sequences with the Mycobacterium and Synechococcus genus.  相似文献   
66.
Subclinical mastitis (SCM) represents a major proportion of the burden of mastitis. Determining somatic cell count (SCC) and electrical conductivity (EC) of milk are useful approaches to detect SCM. In order to correlate grades of SCM with the load of five major mastitis pathogens, 246 milk samples from a handful of organized and unorganized sectors were screened. SCC (>5 × 105/mL) and EC (>6.5 mS/cm) identified 110 (45 %) and 153 (62 %) samples, respectively, to be from SCM cases. Randomly selected SCM-negative samples as well as 186 samples positive by either SCC or EC were then evaluated for isolation of five major mastitis-associated bacteria. Of the 323 isolates obtained, 95 each were S. aureus and coagulase-negative staphylococci (CoNS), 48 were E. coli and 85 were streptococci. There was no association between the distribution of organisms and (a) the different groups of SCC, or (b) organised farms and unorganised sectors. By contrast, there was a significant difference in the distribution of CoNS, and not other species, between organized farms and unorganized sectors. In summary, bacteria were isolated irrespective of the density of somatic cells or the type of farm setting, and the frequency of isolation of CoNS was higher with organized farms. These results suggest the requirement for fine tuning SCC and EC limits and the higher probability for CoNS to be associated with SCM in organized diary sectors, and have implications for the identification, management and control of mastitis in India.  相似文献   
67.
The need for a rapid detection and characterization of biowarfare (BW) agents cannot be over emphasized. With diverse array of potential BW pathogen available presently, rapid identification of the pathogen is crucial, so that specific therapy and control measures can be initiated. We have developed a multiplex polymerase chain reaction based reverse line blot macroarray to simultaneously detect four pathogens of BW importance viz. Bacillus anthracis, Yersinia pestis, Brucella melitensis and Burkholderia pseudomallei. The multiplex PCR utilizes 14 pairs of primers targeting 18 specific markers. These markers include genes which are genus specific, species-specific chromosomal sequences and virulence markers of plasmid origin. The assay was evaluated on various human, environment and animal isolates. The assay w successful in simultaneous detection and characterization of isolates of the four pathogens on as a single platform with sensitivity ranging from 0.3 pg to 0.3 ng of genomic DNA. The assay was able to detect 5 × 102 cfu/ml for B. anthracis, 8 × 102 cfu/ml for Yersinia sp., 1.4 × 102 cfu/ml for B. melitensis and 4 × 102 cfu/ml for B. pseudomallei.  相似文献   
68.
Cataract is a key factor in the morbidity associated with diabetes. While the pathogenesis of diabetic cataract formation is poorly understood, previous research has identified aldose reductase (ALR2) as a key player. To elucidate a potential role for this enzyme in diabetic cataract formation, we created a series of transgenic mice designed for expression of human ALR2 (AKR1B1) in epithelial and outer cortical fiber cells of the lens. One of the founder lines, designated PAR39, developed an early onset cataract that involved formation of a plaque of cells at the anterior aspect of the lens. These cells appear to separate from the anterior epithelium and undergo a dramatic change that is reminiscent of the epithelial to mesenchymal transition (EMT). We characterized this phenotype in the PAR39 strain by examining rates of cell proliferation and by immunostaining for markers of EMT. Incorporation of the thymidine analog bromodeoxyuridine (BrdU) was used to estimate cell proliferation in two functional areas of the lens epithelium: the mitotically active germinative zone (GZ) and the less proliferative center zone (CZ). Staining cell nuclei with diamido 4',6-diamidino-2-phenylindole (DAPI) was used to establish a total cell count in the demarcated areas. Lens epithelium in PAR39 transgenic mice demonstrated a decrease in the percentage of BrdU/DAPI staining within the GZ as compared to nontransgenic littermate controls (8.1% vs. 10.9%). A similar decrease in BrdU/DAPI was observed in the CZ (0.6% compared to 3.3%). However, cell density was greater within the GZ of PAR39 mice as compared with nontransgenic controls, while it was not significantly different in the CZ among the two groups. Furthermore, cells associated with the epithelial plaque did not stain positive for BrdU, but were strongly positive for alpha-smooth muscle actin, a classical marker for EMT. These findings suggest that ALR2 over-expression is associated with an alteration in the balance between proliferation and apoptosis of epithelial cells in the mouse lens, and that cells associated with epithelial plaques in the PAR39 lens have features in common with cells undergoing EMT.  相似文献   
69.
The present study was aimed to investigate the modulatory role of plasma folate and eight putatively functional polymorphisms of one-carbon metabolism on catecholamine methyltransferase (COMT)-mediated oxidative DNA damage and breast cancer risk. Plasma folate and 8-oxo-2'-deoxyguanosine (8-oxodG) were estimated by commercially available kits, while polymorphisms were screened by PCR-RFLP and PCR-AFLP methods. COMT H108L polymorphism showed independent association with breast cancer (OR: 1.73, 95% CI: 1.31-2.30). No significant interaction was observed between folate status and COMT genotype. Multifactor dimensionality reduction (MDR) analysis gave evidence for the significant epistatic (gene-gene) interactions (p<0.0001) of COMT H108L with reduced folate carrier 1 (RFC1) G80A, thymidylate synthase (TYMS) 5'-UTR 3R2R, TYMS 3'-UTR ins6/de16. Increased plasma 8-oxodG were observed in cases compared to controls (mean +/- SE: 5.59 +/- 0.60 vs. 3.50 +/- 0.40 ng/ml, p<0.004). Plasma folate deficiency alone was not a significant predictor of 8-oxodG elevation. The genotype combinations namely, RFC1 G80A/methionine synthase reductase (MTRR) A66G, RFC1 G80A/SHMT C1420T/TYMS 3R2R and serine hydroxymethyltransferase (SHMT) C1420T/TYMS 3R2R/methionine synthase (MTR) A2756G/COMT H108L were strong predictors of 8-oxodG elevation in the order of risk. To conclude, the current study provides substantial evidence for a cross talk between one-carbon metabolism and COMT catalysis that might influence oxidative DNA damage and breast cancer risk.  相似文献   
70.
The aim of this case–control study is to explore the role of aberrations in xenobiotic metabolism in inducing oxidative DNA damage and altering the susceptibility to breast cancer. Cytochrome P4501A1 (CYP1A1) m1 (OR: 1.41, 95% CI 1.08–1.84), CYP1A1 m4 (OR: 5.13, 95% CI 2.68–9.81), Catecholamine-O-methyl transferase (COMT) H108L (OR: 1.49, 95% CI 1.16–1.92), and glutathione S-transferase (GST) T1 null (OR: 1.68, 95% CI 1.09–2.59) variants showed association with breast cancer risk. Reduced folate carrier 1 (RFC1) 80A/CYP1A1 m1/CYP1A1 m4 and RFC1 80A/thymidylate synthase (TYMS) 5′-UTR 2R/methionine synthase (MTR) 2756G/COMT 108L genetic combinations were found to inflate breast cancer risk under the conditions of low dietary folate (345 ± 110 vs. 379 ± 139 μg/day) and low plasma folate (6.81 ± 1.25 vs. 7.09 ± 1.26 ng/ml) by increasing plasma 8-oxo-2′-deoxyguanosine (8-oxodG). This increase in 8-oxodG is attributed to low methionine (49.38 ± 23.74 vs. 53.90 ± 23.85 μmol/l); low glutathione (378 ± 242 vs. 501 ± 126 μmol/l) and GSTT1 null variant; and hypermethylation of CpG island of extracellular-superoxide dismutase (EC-SOD) (92.78 ± 11.49 vs. 80.45 ± 9.86%), which impair O-methylation of catechol estrogens to methoxy estrogens, conjugation of glutathione to semiquinones/quinones and free radical scavenging respectively. Our results suggest cross-talk between one-carbon metabolism and xenobiotic metabolism influencing oxidative DNA damage and susceptibility to breast cancer.  相似文献   
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