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为了分析CD138免疫磁珠细胞分选的染色体荧光原位杂交(FISH)技术在提高多发性骨髓瘤(MM)细胞遗传学异常检测敏感性的作用。本研究选取我院收治的30例确诊MM的患者为研究对象,分离骨髓单个核细胞,应用探针组合,同时采用2种方法进行细胞遗传学检测:实验组采用CD138免疫磁珠分选浆细胞后行荧光原位杂交技术(MACS-FISH)检测;对照组直接荧光原位杂交技术(D-FISH)检测。结果:30例MM患者,实验组采用CD138 MACS-FISH检出率为83.3%,对照组D-FISH法细胞遗传异常检出率为46.7%,两组差异具有统计学意义(p<0.05)。研究结果表明:分析不同类型的细胞遗传异常,MACS-FISH法1q21检出率为46.7%,RB1检出率为50.0%,Ig H检出率为70.0%,P53检出率为20.0%;D-FISH法检出率分别为23.3%,30.0%、36.7%、10.0%。通过细胞核型分析,30例MM患者中,发现5例患者为异常核型,仅为16.7%,其中1例患者为单一结构异常,复杂异常核型患者为4例。我们的研究结论表明:进行CD138免疫磁珠分选浆细胞的FISH技术在多发性骨髓瘤诊断应用中可显著提高细胞遗传学异常检测敏感性,具有临床推广应用的价值。  相似文献   
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The lipid droplet (LD) is an organelle with vital functions found in nearly all organisms. LD proteomic research has provided fundamentally important insights into this organelle's functions. The review provides a summary of LD proteomic studies conducted across diverse organisms and cell and tissue types. The accumulated proteomic data are reviewed for evidence of a protein targeting mechanism for the organelle. The hypotheses for several specific localization mechanisms based on what is known about targeting mechanisms for other organelles and vesicles are provided. Although the nature of the mechanism is not known, the functional data demonstrate that the targeting mechanism and, indeed, the organelle itself, is conserved from prokaryotes to eukaryotes. It is hoped that the review will help inspire further research leading to novel discoveries in the field.  相似文献   
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Spermatogenesis is a highly ordered developmental program that produces haploid male germ cells. The study of male germ cell development in the mouse has provided unique perspectives into the molecular mechanisms that control cell development and differentiation in mammals, including tissue‐specific gene regulatory programs. An intrinsic challenge in spermatogenesis research is the heterogeneity of germ and somatic cell types present in the testis. Techniques to separate and isolate distinct mouse spermatogenic cell types have great potential to shed light on molecular mechanisms controlling mammalian cell development, while also providing new insights into cellular events important for human reproductive health. Here, we detail a versatile strategy that combines Cre‐lox technology to fluorescently label germ cells, with flow cytometry to discriminate and isolate germ cells in different stages of development for cellular and molecular analyses.  相似文献   
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NG2+ cells have been proven to differentiate into odontoblasts in vivo, and their contribution to odontoblasts is significantly increased, especially after tooth injury. However, their characteristics in vitro, especially under an inflammatory environment, are still not fully understood. Therefore, this study aimed to explore their proliferation, migration, and odontoblastic differentiation ability after treatment with lipopolysaccharide (LPS) in vitro. In our study, NG2 + cells were isolated from the human dental pulp by magnetic‐activated cell sorting, and these isolated cells were proven to be NG2 + by immunostaining. When compared with human dental pulp cells (hDPCs), the NG2 + cells showed no significant differences in cell migration with or without LPS incubation, but their proliferative ability was weaker. When treated with LPS, NG2 + cells expressed elevated levels of pro‐inflammatory cytokines including interleukin‐1β (IL‐1β), IL‐6, IL‐8, and tumor necrosis factor‐α, and among these, the expression of IL‐1β and IL‐6 were higher than that of hDPCs. Their multipotent differentiation potential was confirmed by the induction of odontoblastic and adipogenic differentiation, and LPS increased their odontoblastic differentiation capacity. In the odontoblastic differentiation process, Wnt5a, BMP2, and BMP7 mRNA were increased, while the canonical Wnt‐related genes were decreased. In conclusion, the LPS stimulation promotes the migration, proliferative, and odontoblastic differentiation ability of NG2 + cells from the human dental pulp in vitro, and bone morphogenetic protein and the noncanonical Wnt pathway may be involved in their odontoblastic differentiation. These results indicated their special roles in tooth injury repair and potential application in pulp regeneration.  相似文献   
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The Ajuga reptans L. galactan:galactan galactosyltransferase (ArGGT) is a vacuolar enzyme that synthesizes long-chain raffinose family oligosaccharides (RFOs), the major storage carbohydrates of this plant. ArGGT is structurally and functionally related to acid plant alpha-galactosidases (alpha-Gals) of the glycosylhydrolase family 27, present in the apoplast or the vacuole. Sequence comparison of acid alpha-Gals with ArGGT revealed that they all contain an N-terminal signal sequence and a highly similar core sequence. Additionally, ArGGT and some acid alpha-Gals contain C-terminal extensions with low sequence similarities to each other. Here, we show that the C-terminal pentapeptide, SLQMS, is a non-sequence-specific vacuolar sorting determinant. Analogously, we demonstrate that the C-terminal extensions of selected acid alpha-Gals from Arabidopsis, barley, and rice, are also non-sequence-specific vacuolar sorting determinants, suggesting the presence of at least one vacuolar form of acid alpha-Gal in every plant species.  相似文献   
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