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961.
962.
Recently, it has been revealed that estrogen-related reproductive factors are linked with some early gene expression lesions associated with malignancy in clinically healthy breasts. Accordingly, the aim of the current study was to evaluate the association of expression levels of estrogen-related long noncoding RNAs (lncRNAs) upstream Eleanor (u-Eleanor) and HOX antisense intergenic RNA (HOTAIR) with the different patterns of reproductive factors in breast tissue of healthy women. The subjects of this study were 98 cancer-free women who had undergone cosmetic mammoplasty. The expression levels of u-Eleanor and HOTAIR were measured using quantitative real-time polymerase chain reaction. The results of the current study showed that the women without a history of breastfeeding had a high-level expression of u-Eleanor compared with the women with a breastfeeding duration greater than 6 to 24 months (P = 0.03) as well as the women with a breastfeeding duration of more than 24 months (P = 0.005). Furthermore, a higher expression of u-Eleanor was found in the women with a short breastfeeding duration for 1 to 6 months than that in the women with a breastfeeding duration of greater than 24 months (P = 0.02). In the same way, the results of correlation test (r = −0.258; P = 0.036) and multivariate regression model (β = −0.321; P = 0.023) are indicative of a significant relationship of elevated expression of u-Eleanor with decreasing breastfeeding duration in the women. These findings could be important to identify the molecular mechanisms behind the relationship between a lack or short duration of the breastfeeding and the risk of breast cancer, which has previously been reported by epidemiological studies.  相似文献   
963.
Narrow‐leafed lupin (Lupinus angustifolius L.) cultivation was transformed by 2 dominant vernalization‐insensitive, early flowering time loci known as Ku and Julius (Jul), which allowed expansion into shorter season environments. However, reliance on these loci has limited genetic and phenotypic diversity for environmental adaptation in cultivated lupin. We recently predicted that a 1,423‐bp deletion in the cis‐regulatory region of LanFTc1, a FLOWERING LOCUS T (FT) homologue, derepressed expression of LanFTc1 and was the underlying cause of the Ku phenotype. Here, we surveyed diverse germplasm for LanFTc1 cis‐regulatory variation and identified 2 further deletions of 1,208 and 5,162 bp in the 5' regulatory region, which overlap the 1,423‐bp deletion. Additionally, we confirmed that no other polymorphisms were perfectly associated with vernalization responsiveness. Phenotyping and gene expression analyses revealed that Jul accessions possessed the 5,162‐bp deletion and that the Jul and Ku deletions were equally capable of removing vernalization requirement and up‐regulating gene expression. The 1,208‐bp deletion was associated with intermediate phenology, vernalization responsiveness, and gene expression and therefore may be useful for expanding agronomic adaptation of lupin. This insertion/deletion series may also help resolve how the vernalization response is mediated at the molecular level in legumes.  相似文献   
964.
Chemokines trigger numerous inflammatory responses and modulate the immune system. The interaction between monocyte chemoattractant protein-1 and chemokine receptor 2 (CCR2) may be the cause of atherosclerosis, obesity, and insulin resistance. However, CCR2 is also implicated in other inflammatory diseases such as rheumatoid arthritis, multiple sclerosis, asthma, and neuropathic pain. Therefore, there is a paramount importance of designing potent and selective CCR2 antagonists despite a number of drug candidates failed in clinical trials. In this article, 83 CCR2 antagonists by Jhonson and Jhonson Pharmaceuticals have been considered for robust validated multi-QSAR modeling studies to get an idea about the structural and pharmacophoric requirements for designing more potent CCR2 antagonists. All these QSAR models were validated and statistically reliable. Observations resulted from different modeling studies correlated and validated results of other ones. Finally, depending on these QSAR observations, some new molecules were proposed that may exhibit higher activity against CCR2.  相似文献   
965.
The work presented here explores the structural and physicochemical features important for benzamide-based HDAC3 inhibitors to get an idea about the design aspect of potential inhibitors. A number of molecular modeling studies (3D-QSAR CoMFA and CoMSIA, Bayesian classification modeling) were performed on 113 diverse set of benzamide-based HDAC3 inhibitors. All these models developed are statistically reliable and correlate the SAR observations. Electron withdrawing substitution is favorable but the bulky hydrophobic group at the cap region reduces HDAC3 inhibition. Hydrophobicity and steric feature of the aryl linker function favor the activity. Aryl group substituted benzamide functionality is not favorable for HDAC3 inhibition. The amide function of the benzamide moiety is essential for Zn2+ chelation and the carboxylic acid function may serve as a hydrogen bond acceptor (HBA) feature. Moreover, electron withdrawing substituent at the benzamide moiety influences activity whereas steric and hydrophobic substituents reduce HDAC3 inhibition. Overall, this study may provide a valuable insight on the design of better active HDAC3 inhibitors in future.

Communicated by Ramaswamy H. Sarma  相似文献   

966.
967.
968.
In homozygous mutants of Drosophila lethal-2-giant larvae (lgl), tissues lose apico-basal cell polarity and exhibit ectopic proliferation. Here, we use clonal analysis in the developing eye to investigate the effect of lgl null mutations in the context of surrounding wild-type tissue. lgl clones in the larval eye disc exhibit ectopic expression of the G1-S regulator, Cyclin E, and ectopic proliferation, but do not lose apico-basal cell polarity. Decreasing the perdurance of Lgl protein in larval eye disc clones, by forcing extra proliferation of lgl tissue (using a Minute background), leads to a loss in cell polarity and to more extreme ectopic cell proliferation. Later in development at the pupal stage, lgl mutant photoreceptor cells show aberrant apico-basal cell polarity, but this is not associated with ectopic proliferation, presumably because cells are differentiated. Thus in a clonal context, the ectopic proliferation and cell polarity defects of lgl mutants are separable. Furthermore, lgl mosaic eye discs have alterations in the normal patterns of apoptosis: in larval discs some lgl and wild-type cells at the clonal boundary undergo apoptosis and are excluded from the epithelia, but apoptosis is decreased elsewhere in the disc, and in pupal retinas lgl tissue shows less apoptosis.  相似文献   
969.
970.
The mean intrinsic thermodynamic quantity can be defined by considering the relative population of complex species in the solution and the value of intrinsic thermodynamic quantity corresponds to each step of ligation. In the present study a new method is introduced for analysis of experimental ligand binding data on basis of mean intrinsic thermodynamic quantities. In this regard, a deviation parameter was defined by comparing the non-interacting system with the cooperative interactive one. This parameter can be calculated just by estimation of the first binding constant. A set of relations between this deviation parameter and other binding characteristics, such as mean intrinsic Gibbs free energy of binding and mean Gibbs free energy of site-site interaction, have been developed. This model presents binding mechanism in a unified way that is simple, yet stringent, more straightforward, more reliable and informative. This analyzing method has been successfully applied for evaluation of various systems such as oxygen binding to hemoglobin, laurate and warfarin binding to human serum albumin, and reveals some new biological features of these binding systems.  相似文献   
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