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131.
132.
Phospholipid hydroperoxide glutathione peroxidase (PHGPx) is an ubiquitous antioxidant enzyme, but the exact expression pattern in mammalian tissues is still unknown. The expression and cellular localization of PHGPx mRNA were examined in male mice using real time-polymerase chain reaction and in situ hybridization techniques. The rank order of PHGPx mRNA expression across tissues exhibiting substantial levels of expression was:testes ≫ heart > cerebrum ≥ ileum > stomach = liver = jejunum ≥ epididymis. In testes, PHGPx mRNA was highly expressed in spermiogenic cells and Leydig cells. The signal was also expressed in the molecular layer, Purkinje cell layer, and white matter of cerebellum, the pituicytes of neurohypophysis, the parafollicular cells and follicular basement membrane of thyroid, the exocrine portion of pancreas, the tubular epithelium of kidney, the smooth muscle cells of arteries, and the red pulp of spleen. In the gastrointestinal tract, PHGPx mRNA expression was mainly observed in the keratinized surface epithelium of forestomach, the submucosal glands and serosa layers, and further the Paneth cells of intestines. PHGPx mRNA appeared to be ubiquitously expressed in the parenchyma of heart, liver, and lung. These results indicate that PHGPx exhibits a cell- and tissue-specific expression pattern in mice.  相似文献   
133.
Embryonic germ (EG) cells are undifferentiated stem cells isolated from cultured primordial germ cells (PGC). Porcine EG cell lines with capacities of both in vitro and in vivo differentiation have been established. Because EG cells can be cultured indefinitely in an undifferentiated state, they may be more suitable for nuclear donor cells in nuclear transfer (NT) than somatic cells that have limited lifespan in primary culture. Use of EG cells could be particularly advantageous to provide an inexhaustible source of transgenic cells for NT. In this study the efficiencies of transgenesis and NT using porcine fetal fibroblasts and EG cells were compared. The rate of development to the blastocyst stage was significantly higher in EG cell NT than somatic cell NT (94 of 518, 18.2% vs. 72 of 501, 14.4%). To investigate if EG cells can be used for transgenesis in pigs, green fluorescent protein (GFP) gene was introduced into porcine EG cells. Nuclear transfer embryos using transfected EG cells gave rise to blastocysts (29 of 137, 21.2%) expressing GFP based on observation under fluorescence microscope. The results obtained from the present study suggest that EG cell NT may have advantages over somatic cell NT, and transgenic pigs may be produced using EG cells.  相似文献   
134.
Apoptosis is a barrier to maintaining high viable cell densities in animal cell culture. Silkworm hemolymph and its 30K protein have been reported to exhibit anti-apoptotic activity in various mammalian and insect cell systems. The 30K protein is thermally unstable at temperatures higher than 60 degrees C; however, the silkworm hemolymph heat-treated at 70-80 degrees C still exhibited anti-apoptotic activity. This indicates that silkworm hemolymph contains another anti-apoptotic compound other than 30K protein. In this article, the anti-apoptotic molecule other than 30K protein was found from the silkworm hemolymph and identified. This molecule was storage-protein 2 (SP2), which has no homology with any known anti-apoptotic protein. This molecule was heat-stable up to 80 degrees C, while 30K protein lost its activity at temperatures higher than 60 degrees C. When apoptosis was induced by staurosporine in HeLa cells, SP2 protein suppressed nuclear fragmentation and apoptotic body formation. Moreover, the generation of reactive oxygen species after apoptosis induction was inhibited, which means the inhibition occurred in an early step of the apoptotic process. Inhibition of apoptosis by the SP2 protein would lead to the minimization of cell death during commercial mammalian cell culture.  相似文献   
135.
To better understand organelle genome evolution of the ulvophycean green alga Capsosiphon fulvescens, we sequenced and characterized its complete chloroplast genome. The circular chloroplast genome was 111,561 bp in length with 31.3% GC content that contained 108 genes including 77 protein‐coding genes, two copies of rRNA operons, and 27 tRNAs. In this analysis, we found the two types of isoform, called heteroplasmy, were likely caused by a flip‐flop organization. The flip‐flop mechanism may have caused structural variation and gene conversion in the chloroplast genome of C. fulvescens. In a phylogenetic analysis based on all available ulvophycean chloroplast genome data, including a new C. fulvescens genome, we found three major conflicting signals for C. fulvescens and its sister taxon Pseudoneochloris marina within 70 individual genes: (i) monophyly with Ulotrichales, (ii) monophyly with Ulvales, and (iii) monophyly with the clade of Ulotrichales and Ulvales. Although the 70‐gene concatenated phylogeny supported monophyly with Ulvales for both species, these complex phylogenetic signals of individual genes need further investigations using a data‐rich approach (i.e., organelle genome data) from broader taxon sampling.  相似文献   
136.
On-site genetic detection needs to develop a sensitive and straightforward biosensor without special equipment, which can detect various genetic biomarkers. Hybridization chain reaction (HCR) amplifying signal isothermally could be considered as a good candidate for on-site detection. Here, we developed a novel genetic biosensor on the basis of enzyme-free dual-amplification of universal hybridization chain reaction (uHCR) and hemin/G-quadruplex horseradish peroxidase (HRP)-mimicking DNAzyme. The uHCR is the strategy which enables simple design for multiple target detection by the introduction of target-specific trigger hairpin without changing the whole system according to a target change. Also, HRP-mimicking DNAzyme could produce a sensitive and quantitative colorimetric signal with increased stability with a limit of detection (LOD) of 5.67 nM. The universality of the uHCR biosensor was proven by the detection of four different targets (miR-21, miR-125b, KRAS-Q61K, and BRAF-V600E) for cancer diagnosis. The uHCR biosensor showed specificity that could discriminate single-nucleotide polymorphism. Moreover, the uHCR biosensor could detect targets in the diluted serum sample. Overall, the uHCR biosensor demonstrated the potential for field testing with a simple redesign without complicated steps or special equipment using a universal hairpin system and enzyme-free amplification. This strategy could enable stable and sensitive detection of a variety of targets. Therefore, it could be applied to urgent detection of various pathogens, remote diagnosis, and self-screening of diseases.  相似文献   
137.
138.
Due to the highly immunogenic nature of renal cell carcinoma (RCC), the tumor microenvironment (TME) is enriched with various innate and adaptive immune subsets. In particular, gamma-delta (γδ) T cells can act as potent attractive mediators of adoptive cell transfer immunotherapy because of their unique properties such as non-reliance on major histocompatibility complex expression, their ability to infiltrate human tumors and recognize tumor antigens, relative insensitivity to immune checkpoint molecules, and broad tumor cytotoxicity. Therefore, it is now critical to better characterize human γδ T-cell subsets and their mechanisms in RCCs, especially the stage of differentiation. In this study, we aimed to identify γδ T cells that might have adaptive responses against RCC progression. We characterized γδ T cells in peripheral blood and tumor-infiltrating lymphocytes (TILs) in freshly resected tumor specimens from 20 RCC patients. Furthermore, we performed a gene set enrichment analysis on RNA-sequencing data from The Cancer Genome Atlas (TCGA) derived from normal kidneys and RCC tumors to ascertain the association between γδ T-cell infiltration and anti-cancer immune activity. Notably, RCC-infiltrating CD3low Vγ9Vδ1 T cells with a terminally differentiated effector memory phenotype with up-regulated activation/exhaustion molecules were newly detected as predominant TILs, and the cytotoxic activity of these cells against RCC was confirmed in vitro. In an additional analysis of the TCGA RCC dataset, γδ T-cell enrichment scores correlated strongly with those for CTLs, Th1 cells, “exhausted” T cells, and M1 macrophages, suggesting active involvement of γδ T cells in anti-tumor rather than pro-tumor activity, and Vδ1 cells were more abundant than Vδ2 or Vδ3 cells in RCC tumor samples. Thus, we posit that Vγ9Vδ1 T cells may represent an excellent candidate for adoptive immunotherapy in RCC patients with a high risk of relapse after surgery.  相似文献   
139.
Extracellular vesicles, which are highly conserved in most cells, contain biologically active substances. The vesicles and substances interact with cells and impact physiological mechanisms. The skin is the most external organ and is in direct contact with the external environment. Photoaging and skin damage are caused by extrinsic factors. The formation of wrinkles is a major indicator of skin aging and is caused by a decrease in collagen and hyaluronic acid. MMP-1 expression is also increased. Due to accruing damage, skin aging reduces the ability of the skin barrier, thereby lowering the skin’s ability to contain water and increasing the amount of water loss. L. plantarum suppresses various harmful bacteria by secreting an antimicrobial substance. L. plantarum is also found in the skin, and research on the interactions between the bacteria and the skin is in progress. Although several studies have investigated L. plantarum, there are only a limited number of studies on extracellular vesicles (EV) derived from L. plantarum, especially in relation to skin aging. Herein, we isolated EVs that were secreted from L. plantarum of women in their 20s (LpEVs). We then investigated the effect of LpEVs on skin aging in CCD986sk. We showed that LpEVs modulated the mRNA expression of ECM related genes in vitro. Furthermore, LpEVs suppressed wrinkle formation and pigmentation in clinical trials. These results demonstrated that LpEVs have a great effect on skin aging by regulating ECM related genes. In addition, our study offers important evidence on the depigmentation effect of LpEVs.  相似文献   
140.
TNM stage still serves as the best prognostic marker in gastric cancer (GC). The next step is to find prognostic biomarkers that detect subgroups with different prognoses in the same TNM stage. In this study, the expression levels of epidermal growth factor receptor (EGFR) and cyclin D1 were assessed in 96 tissue samples, including non-tumorous tissue, adenoma, and carcinoma. Then, the prognostic impact of EGFR and cyclin D1 was retrospectively investigated in 316 patients who underwent R0 resection for GC. EGFR positivity increased as gastric tissue became malignant, and cyclin D1 positivity was increased in all the tumorous tissues. However, there was no survival difference caused by the EGFR positivity, while the cyclin D1-postive group had worse overall survival (OS) than the cyclin D1-negative group in stage I GC (10-year survival rate (10-YSR): 62.8% vs. 86.5%, p = 0.010). In subgroup analyses for the propensity score-matched (PSM) cohort, there were also significant differences in the OS according to the cyclin D1 positivity in stage I GC but not in stage II and III GC. Upon multivariate analysis, cyclin D1 positivity was an independent prognostic factor in stage I GC. In conclusion, cyclin D1 may be a useful biomarker for predicting prognosis in stage I GC.  相似文献   
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