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991.
BackgroundThree-dimensional computed tomographic imaging has become popular in clinical evaluation, treatment planning, surgical simulation, and outcome assessment for maxillofacial intervention. The purposes of this study were to investigate whether there is any correlation among landmark-based horizontal reference planes and to validate the reproducibility and reliability of landmark identification.ResultsA total of 30 patients with facial deformity and malocclusion—10 patients with facial symmetry, 10 patients with facial asymmetry, and 10 patients with cleft lip and palate—were recruited. Comparing the differences among the 5 reference planes showed no statistically significant difference among all patient groups. Regarding intraobserver reproducibility, the mean differences in the 3 coordinates varied from 0 to 0.35 mm, with correlation coefficients between 0.96 and 1.0, showing high correlation between repeated tests. Regarding interobserver reliability, the mean differences among the 3 coordinates varied from 0 to 0.47 mm, with correlation coefficients between 0.88 and 1.0, exhibiting high correlation between the different examiners.ConclusionsThe 5 horizontal reference planes were reliable and comparable for 3D craniomaxillofacial analysis. These reference planes were useful in standardizing the orientation of 3D skull models.  相似文献   
992.
Baicalein, a widely used Chinese herbal medicine, has multiple pharmacological activities. However, the precise mechanisms of the anti-proliferation and anti-metastatic effects of baicalein on gallbladder cancer (GBC) remain poorly understood. Therefore, the aim of this study was to assess the anti-proliferation and anti-metastatic effects of baicalein and the related mechanism(s) on GBC. In the present study, we found that treatment with baicalein induced a significant inhibitory effect on proliferation and promoted apoptosis in GBC-SD and SGC996 cells, two widely used gallbladder cancer cell lines. Additionally, treatment with baicalein inhibited the metastasis of GBC cells. Moreover, we demonstrated for the first time that baicalein inhibited GBC cell growth and metastasis via down-regulation of the expression level of Zinc finger protein X-linked (ZFX). In conclusion, our studies suggest that baicalein may be a potential phytochemical flavonoid for therapeutics of GBC and ZFX may serve as a molecular marker or predictive target for GBC.  相似文献   
993.
目的:观察噪声或二硫化碳(CS2)暴露对大鼠外侧膝状体(LGB)神经元光反应的影响及二者的联合效应。方法:脉冲噪声刺激和光栅刺激由计算机控制输出,CS2通过皮下注射,运用电生理学方法记录LGB神经元电活动。结果:噪声暴露后有21%的神经元光反应被抑制,当噪声持续时,抑制程度有增强的趋势,呈现出剂量效应关系。不同剂量的CS2暴露,神经元受到不同程度的抑制,亦呈剂量一效应关系。噪声和CS2同时作用时,呈一定的协同作用。结论:噪声或者CS2的单独作用可明显抑制外膝体神经元的光反应,在共同作用时存在联合效应,主要表现为协同效应。  相似文献   
994.
A series of novel 8-amino-1,3-disubstituted-imidazo[1,5-a]pyrazines was designed and synthesized as IGF-IR inhibitors.  相似文献   
995.
Diterpenoids isolated from Labiatae family herbs have strong antitumor activities with low toxicity. In this study, Eriocalyxin B (EriB), a diterpenoid extracted from Isodon eriocalyx, was tested on human leukemia/lymphoma cells and murine leukemia models. Acute myeloid leukemia cell line Kasumi-1 was most sensitive to EriB. Significant apoptosis was observed, concomitant with Bcl-2/Bcl-XL downregulation, mitochondrial instability and caspase-3 activation. AML1-ETO oncoprotein was degraded in parallel to caspase-3 activation. EriB-mediated apoptosis was associated with NF-kappaB inactivation by preventing NF-kappaB nuclear translocation and inducing IkappaBalpha cleavage, and disturbance of MAPK pathway by downregulating ERK1/2 phosphorylation and activating AP-1. Without affecting normal hematopoietic progenitor cells proliferation, EriB was effective on primary t(8;21) leukemia blasts and caused AML1-ETO degradation. In murine t(8;21) leukemia models, EriB remarkably prolonged the survival time or decreased the xenograft tumor size. Together, EriB might be a potential treatment for t(8;21) leukemia by targeting AML1-ETO oncoprotein and activating apoptosis pathways.  相似文献   
996.
997.
Du JZ  Sun TM  Weng SQ  Chen XS  Wang J 《Biomacromolecules》2007,8(11):3375-3381
Novel biodegradable hydrogels by photo-cross-linking macromers based on polyphosphoesters and poly(ethylene glycol) (PEG) are reported. Photo-cross-linkable macromers were synthesized by ring-opening polymerization of the cyclic phosphoester monomer 2-(2-oxo-1,3,2-dioxaphospholoyloxy) ethyl methacrylate (OPEMA) using PEG as the initiator and stannous octoate as the catalyst. The macromers were characterized by 1H NMR, Fourier transform infrared spectroscopy, and gel permeation chromatography measurements. The content of polyphosphoester in the macromer was controlled by varying the feed ratio of OPEMA to PEG. Hydrogels were fabricated by exposing aqueous solutions of macromers with 0.05% (w/w) photoinitiator to UV light irradiation, and their swelling kinetics as well as degradation behaviors were evaluated. The results demonstrated that cross-linking density and pH values strongly affected the degradation rates. The macromers was compatible to osteoblast cells, not exhibiting significant cytotoxicity up to 0.5 mg/mL. "Live/dead" cell staining assay also demonstrated that a large majority of the osteoblast cells remained viable after encapsulation into the hydrogel constructs, showing their potential as tissue engineering scaffolds.  相似文献   
998.
Male mice that are homozygous for the juvenile spermatogonial depletion (jsd) mutation in the Utp14b gene undergo several waves of spermatogenesis. However, spermatogonial differentiation ceases and in adults, spermatogonia are the only germ cells that remain. To understand further the blockage in spermatogonial differentiation in Utp14b(jsd) mutant mice, we correlated the rate and severity of spermatogonial depletion and the restoration of spermatogenesis following the suppression of testosterone or elevation of testicular temperature with the genetic background. Testes from Utp14b(jsd) mutant mice on B6, C3H, and mixed C3H-B6-129 (HB129) genetic backgrounds all showed steady decreases in the numbers of normal spermatogonia between 8 wk and 20 wk of age. The percentages of tubules with differentiating germ cells were higher and the spermatogonia were more advanced in C3H- background than in B6- or HB129-background Utp14b(jsd) mice. Genetic crosses showed that the source of the Y chromosome was a major factor in determining the severity of spermatogonial depletion in Utp14b(jsd) mutant mice. When Utp14b(jsd) mutants were subjected to total androgen ablation or unilateral cryptorchidization, spermatogenic development recovered markedly in the C3H and HB129 background but showed less recovery in the B6-background mice. The differences noted between the strains in terms of the severity of spermatogonial depletion were not dependent upon testosterone level or scrotal temperature but correlated with the magnitudes of the effects of elevated temperature on normal and Utp14b(jsd) mutant spermatogenic cells. Thus, the abilities of germ cells in certain strains to survive elevated temperatures may be related to their abilities to maintain some degree of differentiation potential after the Utp14b(jsd) gene is mutated.  相似文献   
999.
LARGE is a putative glycosyltransferase found to be mutated in mice with myodystrophy or patients with congenital muscular dystrophy. By homology searches, we identified in the Dictyostelium discoideum genome four open reading frames, i.e. gnt12-15, encoding proteins with sequence similarity to LARGE. Semi-quantitative RT-PCR analysis revealed distinct temporal expression patterns of the four gnt genes throughout Dictyostelium development. To explore the gene function, we performed targeted disruptions of gnt14 and gnt15. The gnt14(-) strains showed no obvious phenotypes. However, gnt15(-) cells grew slowly, changed in morphology, and displayed a developmental phenotype arresting at early stages. Compared with the wild type, gnt15(-) cells were more adhesive and exhibited altered levels of some surface adhesion molecules. Moreover, lectin-binding analysis demonstrated that gnt15 disruption affected profiles of membrane glycoproteins. Taken together, our data suggest that Gnt15 is essential for Dictyostelium development and may have a role in modulating cell adhesion and glycosylation.  相似文献   
1000.
Kawasaki disease (KD) typically occurs in children aged under 5 years and can cause coronary artery lesions (CALs). Early diagnosis and treatment with intravenous immunoglobulin can reduce the occurrence of CALs; therefore, identifying a good biomarker for diagnosing KD is essential. Here, using next-generation sequencing in patients with recurrent KD, those with viral infection, and healthy controls, we identified dysregulated circulating microRNAs as diagnostic biomarkers for KD. Pathway enrichment analysis illustrated the putative role of these miRNAs in KD progression. Their expression levels were validated using real-time polymerase chain reaction (qPCR). Fifteen dysregulated circulating miRNAs (fold changes >2 and <0.5) were differentially expressed in the recurrent KD group compared with the viral infection and control groups. These miRNAs were significantly involved in the transforming growth factor-β, epithelial–mesenchymal transition, and cell apoptosis signaling pathways. Notably, their expression levels were frequently restored after intravenous immunoglobulin treatment. Among the candidates, miR-24-3p expression level was significantly higher in patients with recurrent KD compared with healthy controls or viral infection controls (p < 0.001). Receiver operating characteristic analysis revealed that high miR-24-3p expression levels may be a potential biomarker for KD diagnosis. In conclusion, we identified miR-24-3p significantly higher in KD patients, which may be a potential diagnostic biomarker for KD.  相似文献   
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