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排序方式: 共有663条查询结果,搜索用时 31 毫秒
1.
N Fatma D P Singh T Shinohara L T Chylack 《The Journal of biological chemistry》2001,276(52):48899-48907
Antioxidant protein 2 (AOP2), a member of the newly defined family of thiol-specific antioxidant proteins, has been shown to remove H(2)O(2) and protect proteins and DNA from oxidative stress. Here we report that LEDGF is one of the regulatory factors for the AOP2 gene. We found that LEDGF bound to the heat shock element and to stress-related elements in the AOP2 promoter. It trans-activated expression of AOP2-CAT in COS-7 cells and lens epithelial cells overexpressing LEDGF. Mutations in the heat shock element and stress-related elements of the AOP2 promoter reduced LEDGF-dependent trans-activation. Lens epithelial cells showed a higher level of AOP2 mRNA in the presence of LEDGF. Cells overexpressing LEDGF exhibited a higher level of AOP2 protein, the level of which was directly related to the increase in cellular protection. Thus, LEDGF, by activating the AOP2 gene, protected and enhanced the survival of cells under oxidative stress. 相似文献
2.
Silan F Gultekin Y Atik S Kilinc D Alan C Yildiz F Uludag A Ozdemir O 《Molecular biology reports》2012,39(2):1595-1599
Prostate cancer is a common malignancy that develops by structural mutation(s) and/or other genetic alterations in specific
genes.The G to T transversions in codon 12 and C to T transitions in codon 13 of KRAS proto-oncogene are predominant point
mutations that occur in about 20% of different cancers in human. In the current study it was aimed to investigate the prevalence
and predictive significance of KRAS mutations in patients with prostate carcinomas. In a total of 30 fresh tumoural tissue
specimens were investigated in patients with prostate carcinoma. All tumoural specimens were histo-pathologically diagnosed
and genotyped for codon 12, 13 KRAS point mutations by reverse hybridisation and direct sequencing methods. KRAS mutations
were found in 12 (40%) samples with 29 samples deriving from adenocarcinomas and 1 sample was small cell prostate carcinoma.
In 1 (3.44%) sample codon 12 was found to be mutated and in 2 (6.8%) samples codon 13 and in 9 (31%) samples combined codon
12 and 13 were found to be mutated particularly in higher grade of tumoural tissues. Our study, based on representative collection
of human prostate tumours, indicates that combined mutations in codons 12 and 13 KRAS are relatively infrequent and most commonly
occur in prostate carcinomas. 相似文献
3.
K. S. Ramaswamy Claudio D. Carrasco Tasneem Fatma † James W. Golden 《Molecular microbiology》1997,23(6):1241-1249
The fdxN element, along with two other DNA elements, is excised from the chromosome during heterocyst differentiation in Anabaena sp. strain PCC 7120. Previous work showed that rearrangement of the fdxN element requires the xisF gene, which encodes a site-specific recombinase, and suggested that at least one other heterocyst-specific factor is involved. Here we report that the xisH and xisl genes are necessary for the heterocyst-specific excision of the fdxN element. Deletion of a 3.2 kb region downstream of the xisF gene blocked the fdxN-element rearrangement in hetero-cysts. The 3.2 kb deletion was complemented by the two overlapping genes xisH and xisl. Interestingly, extra copies of xlsHI on a replicating plasmid resulted in the xisF-dependent excision of the fdxN element in vegetative cells. Therefore, xisHI are involved in the control of cell-type specificity of the fdxN rearrangement. The xisHI genes had no effect on the two other DNA rearrangements. The xisHl-induced excision of the fdxN element produced strains lacking the element and demonstrates that the 55 kb element contains no essential genes. xisH and xisl do not show similarity to any known genes. 相似文献
4.
The embryonic poly(A)-binding protein (EPAB) functions in the translational regulation of the maternal messenger RNAs (mRNAs) required during oocyte maturation, fertilization, and early embryo development. Since there is no antibody specific to mammalian EPAB protein, all studies related to the Epab gene could be performed at the mRNA levels except for the investigations in the Xenopus. In this study, we have produced an EPAB-specific antibody. When we examined its expressional distribution in the mouse gonadal and somatic tissues, the EPAB protein was found to be expressed only in the mouse ovary and testis tissues, but it is undetectable level in the somatic tissues including stomach, liver, heart, small intestine, and kidney. Additionally, the spatial and temporal expression patterns of the EPAB and poly(A)-binding protein cytoplasmic 1 (PABPC1) proteins were analyzed in the mouse germinal vesicle (GV) and metaphase II (MII) oocytes, one-cell, and two-cell embryos. While EPAB expression gradually decreased from GV oocytes to two-cell embryos, the PABPC1 protein level progressively increased from GV oocytes to one-cell embryos and remarkably declined in the two-cell embryos ( P < 0.05). We have also described herein that the EPAB protein interacted with Epab, Pabpc1, Ccnb1, Gdf9, and Bmp15 mRNAs dependent upon the developmental stages of the mouse oocytes and early embryos. As a result, we have first produced an EPAB-specific antibody and characterized its expression patterns and interacting mRNAs in the mouse oocytes and early embryos. The findings suggest that EPAB in cooperation with PABPC1 implicate in the translational control of maternal mRNAs during oogenesis and early embryo development. 相似文献
5.
Fatma Bouchaala Rabeb Laatar Mariam Lahiani Amira Zouabi Rihab Borji Haithem Rebai 《Chronobiology international》2020,37(2):227-235
ABSTRACTObjective: This study explored the time of day effect of balance performance, functional capacities and risk of fall in three different times in patients with rheumatoid arthritis (RA) and the association between these variations and those of RA symptoms.Methods: A “discontinual” protocol, composed of three test sessions, carried out at 6 am, 2 pm and 10 pm was set up, in order to investigate the time of day effect of balance performance, functional capacities, risk of fall, stiffness, range of motion, swollen and painful joints in women with RA.Results: Time Up and Go Test (TUGT), Functional Reach Test (FRT) and tinetti test scores were significantly higher (p < .01) at 6 am and at 10 pm compared to 2 pm. Stiffness, range of motion, swollen and painful joints values were significantly higher (p < .01) at 6 am and at 10 pm compared to 2 pm. A significant difference was observed on the stiffness, range of motion and swollen joints values between 6 am and 10 pm that were higher at 6 am (p < .05).Using Pearson’s coefficient, correlations were found between RA symptom values; and TUGT, FRT and Tinetti test scores.Conclusion: Results showed a time of day effect of balance performance, functional capacities and risk of falls in women with RA. This variation indicates an alteration of performance at 6 am and 10 pm. Fluctuations of stiffness, limited range of motion, swollen and painful joints noted are concomitant to those of balance performance, functional capacities, and risk of fall.Abbreviations: RA: rheumatoid arthritis; H&O questionnaire: Horne and Ostberg questionnaire; PSQI: Pittsburgh sleep quality index; HAQ: health assessment questionnaire; SF-36: the short form-36; WOMAC: Western Ontario and McMaster Universities Osteoarthritis Index; TUGT: Time Up and Go Test; FRT: Functional Reach Test 相似文献
6.
Fatma A. Aleem M.D. Ph.D. Harold Schulman M.D. 《Prostaglandins & other lipid mediators》1975,9(3):495-500
Placental progesterone contents were studied in 10 patients therapeutically aborted at midtrimester by intraamniotic infusions of hypertonic saline, and from 14 patients (12–20 weeks) aborted by intraamniotic instillation of prostaglandin F2∝. The mean S.E. of the progesterone was 1.99± 0.07 ug/g. placental tissue in the first group, while with prostaglandin abortion the placental progesterone was 1.45± 0.09 ug/g. tissue, which is significantly lower than the results in the first group (P=0.001). The possible mechanism of action of prostaglandin as an effective abortifacient is discussed. 相似文献
7.
Anush Kosakyan Fatma Gomaa Edward A.D. Mitchell Thierry J. Heger Enrique Lara 《European journal of protistology》2013,49(2):222-237
Species identification by means of morphology is often problematic in protists. Nebela tincta–collaris–bohemica (Arcellinida) is a species complex of small to medium-sized (ca.100 μm) testate amoebae common in peat bogs and forest soils. The taxonomic validity of characters used to define species within this group is debated and causes confusion in studies of biogeography, and applications in palaeoecology.We examined the relationship between morphological and genetic diversity within this species complex by combined analyses of light microscopy imaging and Cytochrome Oxidase Subunit 1(COI) sequences obtained from the same individual amoeba cells. Our goals were (1) to clarify the taxonomy and the phylogenetic relationships within this group, and (2) to evaluate if individual genotypes corresponded to specific morphotypes and the extent of phenotypic plasticity.We show here that small variations in test morphology that have been often overlooked by traditional taxonomy correspond to distinct haplotypes. We therefore revise the taxonomy of the group. We redefine Nebela tincta (Leidy) Kosakyan et Lara and N. collaris (Ehrenberg 1848) Kosakyan et Gomaa, change N. tincta var. rotunda Penard to N. rotunda (Penard 1890), describe three new species: N. guttata n. sp. Kosakyan et Lara, N. pechorensis n. sp. Kosakyan et Mitchell, and N. aliciae n. sp. Mitchell et Lara. 相似文献
8.
Luc Demange Fatma Nait Abdellah Olivier Lozach Yoan Ferandin Nohad Gresh Laurent Meijer Hervé Galons 《Bioorganic & medicinal chemistry letters》2013,23(1):125-131
Cyclin dependent kinase 5 (CDK5) is a serine/threonine kinase belonging to the cyclin dependent kinase (CDK) family. CDK5 is involved in numerous neuronal diseases (including Alzheimer’s or Parkinson’s diseases, stroke, traumatic brain injury), pain signaling and cell migration. In the present Letter, we describe syntheses and biological evaluations of new 2,6,9-trisubstituted purines, structurally related to roscovitine, a promising CDK inhibitor currently in clinical trials (CDK1/Cyclin B, IC50 = 350 nM; CDK5/p25, IC50 = 200 nM). These new molecules were synthesized using an original Buchwald–Hartwig catalytic procedure; several compounds (3j, 3k, 3l, 3e, 4k, 6b, 6c) displayed potent kinase inhibitory potencies against CDK5 (IC50 values ranging from 17 to 50 nM) and showed significant cell death inducing activities (IC50 values ranging from 2 to 9 μM on SH-SY5Y). The docking of the inhibitors into the ATP binding domain of the CDK5 catalytic site highlighted the discriminatory effect of a hydrogen bond involving the CDK5 Lys-89. In addition, the calculated final energy balances for complexation measured for several inhibitors is consistent with the ranking of the IC50 values. Lastly, we observed that several compounds exhibit submicromolar activities against DYRK1A (dual specificity, tyrosine phosphorylation regulated kinase 1A), a kinase involved in Down syndrome and Alzheimer’s disease (3g, 3h, 4m; IC50 values ranging from 300 to 400 nM). 相似文献
9.
Mustafa Çelik Fatma Ünal Deniz Yüzbaşıoğlu Serkan Yılmaz Hüseyin Aksoy Şengül Karaman 《Cytotechnology》2006,51(2):99-104
In this investigation, clastogenic effects of Thymus kotschyanus var. glabrescens Boiss. extract (TE) and anticlastogenic effects of this extract against Mitomycin C (MMC) induced chromosome damage have been evaluated in human peripheral blood lymphocytes in vitro. Two series of experiments were conducted. In the first, only 10−5, 10−4, 10−3 and 10−2 μl ml−1 concentrations of TE were used for 48 h to detect potential clastogenicity. In the second, MMC (0.38 μg ml−1) plus 10−5, 10−4, 10−3 and 10−2 μl ml−1 concentrations of TE were used for 48 h to determine anticlastogenic effects. TE did not increase sister chromatid exchanges (SCEs) (except 10−2 μl ml concentration) and chromosome aberrations (CAs) significantly compared with negative and solvent controls. However, it decreased the frequency of MMC induced chromosome aberrations. Decreasing was significant at 10−4, 10−3 and 10−2 μl ml−1 concentrations. On the other hand, TE significantly increased MMC-induced SCEs for all treatment groups compared with positive control. 相似文献
10.
Whole‐cell biocatalysis for C–H oxyfunctionalization depends on and is often limited by O2 mass transfer. In contrast to oxygenases, molybdenum hydroxylases use water instead of O2 as an oxygen donor and thus have the potential to relieve O2 mass transfer limitations. Molybdenum hydroxylases may even allow anaerobic oxyfunctionalization when coupled to anaerobic respiration. To evaluate this option, the coupling of quinoline hydroxylation to denitrification is tested under anaerobic conditions employing Pseudomonas putida (P. putida) 86, capable of aerobic growth on quinoline. P. putida 86 reduces both nitrate and nitrite, but at low rates, which does not enable significant growth and quinoline hydroxylation. Introduction of the nitrate reductase from Pseudomonas aeruginosa enables considerable specific quinoline hydroxylation activity (6.9 U gCDW?1) under anaerobic conditions with nitrate as an electron acceptor and 2‐hydroxyquinoline as the sole product (further metabolization depends on O2). Hydroxylation‐derived electrons are efficiently directed to nitrate, accounting for 38% of the respiratory activity. This study shows that molybdenum hydroxylase‐based whole‐cell biocatalysts enable completely anaerobic carbon oxyfunctionalization when coupled to alternative respiration schemes such as nitrate respiration. 相似文献