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101.
斜纹夜蛾核型多角体病毒BamHI—J片段序列分析   总被引:2,自引:2,他引:2  
报道了斜纹夜蛾核型多角体病毒(SpltMNPV)BamHI-J片段的序列结构。该片段定位于SpltMNPV基因组25.8-29.9图单位(msp unit),包括4个完整的开放读码框,几丁质酶基因(chiA)的3′端部分序列和一个同源区(hr)的部分序列。4个完整的读码框包括lef-8基因,杆状病毒J结构域蛋白基因(baculovirus J domain protein gene,bjdp),ORF570和ORF165。序列分离表明:ORF570与毒蛾核型多角体病毒(Lymantria dispar MNPV)的解旋酶-2基因有31%的氨基酸同源性。ORF165为SpltMNPV特有。J结构域蛋白在其他杆状病毒基因组中尚未见报道,其氨基酸序列N端存在J结构域,推断该蛋白质具有与DnaJ蛋白类似特征。lef-8基因编码的氨基酸与已报道的杆状病毒基因组中的lef-8基因编码的氨基酸具有高的同源性,且其C端具有与其他杆状病毒LEF-8类似的保守序列CIKICGIHGQKG。  相似文献   
102.
摘要 目的:探讨龙血竭胶囊合九华膏对环状混合痔(RMH)术后患者创面愈合、血清炎性因子和免疫功能的影响。方法:选取2016年7月~2019年12月期间我院收治的RMH患者93例,根据随机数字表法分为对照组(n=46,马应龙麝香痔疮膏治疗)和研究组(n=47,龙血竭胶囊合九华膏治疗),比较两组患者疗效、创面愈合情况、不良反应、血清炎性因子和免疫功能。结果:治疗10 d后,研究组的临床总有效率为89.36%(42/47),高于对照组的71.74%(33/46)(P<0.05)。两组治疗10 d后创面渗液、水肿、疼痛、创面肉芽组织评分下降,创面面积减小,且研究组低于对照组(P<0.05)。两组治疗10 d后肿瘤坏死因子-α(TNF-α)、白介素-6(IL-6)、白介素-2(IL-2)均下降,且研究组低于对照组(P<0.05)。两组治疗10 d后免疫球蛋白G(IgG)、免疫球蛋白A(IgA)、免疫球蛋白M(IgM)均升高,且研究组高于对照组(P<0.05)。研究组并发症发生率低于对照组(P<0.05)。结论:RMH患者术后采用龙血竭胶囊合九华膏治疗,疗效较好,可有效促进创面愈合,减轻炎症反应,改善机体免疫功能,同时还可减少并发症发生率。  相似文献   
103.

Background

Accumulating evidence indicates that RNA oxidation is involved in a wide variety of neurological diseases and may be associated with neuronal deterioration during the process of neurodegeneration. However, previous studies were done in postmortem tissues or cultured neurons. Here, we used transgenic mice to demonstrate the role of RNA oxidation in the process of neurodegeneration.

Methodology/Principal Findings

We demonstrated that messenger RNA (mRNA) oxidation is a common feature in amyotrophic lateral sclerosis (ALS) patients as well as in many different transgenic mice expressing familial ALS-linked mutant copper-zinc superoxide dismutase (SOD1). In mutant SOD1 mice, increased mRNA oxidation primarily occurs in the motor neurons and oligodendrocytes of the spinal cord at an early, pre-symptomatic stage. Identification of oxidized mRNA species revealed that some species are more vulnerable to oxidative damage, and importantly, many oxidized mRNA species have been implicated in the pathogenesis of ALS. Oxidative modification of mRNA causes reduced protein expression. Reduced mRNA oxidation by vitamin E restores protein expression and partially protects motor neurons.

Conclusion/Significance

These findings suggest that mRNA oxidation is an early event associated with motor neuron deterioration in ALS, and may be also a common early event preceding neuron degeneration in other neurological diseases.  相似文献   
104.
Xiu  Fan  Xu  Siqi  Zhang  Chun  Wang  Li 《Russian Journal of Bioorganic Chemistry》2021,47(2):524-534
Russian Journal of Bioorganic Chemistry - A new series of N-benzylpiperidine 8-hydroxyquinoline derivatives were synthesized and evaluated as cholinesterase inhibitors, metal ion chelators and...  相似文献   
105.
Chlamydia trachomatis is the most common sexually transmitted pathogen globally, causing serious health problems and representing a burden on public health. A new variant of C. trachomatis (nvCT) that carries mutations (C1514T, C1515T and G1523A) in the 23S rRNA gene has eluded detection in Aptima Combo 2 assays. This has led to false negatives in diagnostics tests and poses a challenge for C. trachomatis diagnostics on a global level. In this study, we developed a simple and cost-effective assay to identify C. trachomatis, with a potential application to screen for nvCT. We developed a screening assay based on high-resolution melting (HRM), targeting the 23S rRNA gene and cryptic plasmid. To evaluate the performance of the assay, 404 archived C. trachomatis DNA specimens and 570 extracted clinical specimens were analysed. Our HRM assay not only identified C. trachomatis in clinical specimens, but also correctly differentiated nvCT carrying C1514T, C1515T and G1523A mutations from the wild-type. We observed no cross-reactions with other clinically related agents, and the limit of detection was 11.26 (95% CI; 7.61–31.82) copies per reaction. Implementation of this screening assay could reduce detection times and costs for C. trachomatis diagnoses, and facilitate increased research on the presence and monitoring of nvCT.  相似文献   
106.
T cell‒mediated rejection (TCMR) and antibody-mediated rejection (ABMR) are severe post-transplantation complications for heart transplantation (HTx), whose molecular and immunological pathogenesis remains unclear. In the present study, the mRNA microarray data set GSE124897 containing 645 stable, 52 TCMR and 144 ABMR endomyocardial biopsies was obtained to screen for differentially expressed genes (DEGs) between rejected and stable HTx samples and to investigate immune cell infiltration. Functional enrichment analyses indicated roles of the DEGs primarily in immune-related mechanisms. Protein-protein interaction networks were then constructed, and ICAM1, CD44, HLA-A and HLA-B were identified as hub genes using the maximal clique centrality method. Immune cell infiltration analysis revealed differences in adaptive and innate immune cell populations between TCMR, ABMR and stable HTx samples. Additionally, hub gene expression levels significantly correlated with the degree and composition of immune cell infiltration in HTx rejection samples. Furthermore, drug-gene interactions were constructed, and 12 FDA-approved drugs were predicted to target hub genes. Finally, an external GSE2596 data set was used to validate the expression of the hub genes, and ROC curves indicated all four hub genes had promising diagnostic value for HTx rejection. This study provides a comprehensive perspective of molecular and immunological regulatory mechanisms underlying HTx rejection.  相似文献   
107.
108.
Thlaspi caerulescens L. is well known as a Zn/Cd hyperaccumulator. The genetic manipulation of T. caerulescens through transgenic technology can modify plant features for use in phytoremediation. Here, we describe the efficient transformation of T. caerulescens using Agrobacterium tumefaciens strain EHA105 harboring a binary vector pBI121 with the nptII gene as a selectable marker, the gus gene as a reporter and a foreign catalase gene. Based on the optimal concentration of growth regulators, the shoot cluster regeneration system via callus phase provided the basis of the genetic transformation in T. caerulescens. The key variables in transformation were examined, such as co-cultivation period and bacterial suspension density. Optimizing factors for T-DNA delivery resulted in kanamycin-resistant transgenic shoots with transformation efficiency more than 20%, proven by histochemical GUS assay and PCR analysis. Southern analysis of nptII and RT-PCR of catalase gene demonstrated that the foreign genes were integrated in the genome of transformed plantlets. Moreover, the activity of catalase enzyme in transgenic plants was obviously higher than in wild-type plants. This method offers new prospects for the genetic engineering of this important hyperaccumulator species.  相似文献   
109.
110.
Corin is a membrane-bound protease essential for activating natriuretic peptides and regulating blood pressure. Human corin has 19 predicted N-glycosylation sites in its extracellular domains. It has been shown that N-glycans are required for corin cell surface expression and zymogen activation. It remains unknown, however, how N-glycans at different sites may regulate corin biosynthesis and processing. In this study, we examined corin mutants, in which each of the 19 predicted N-glycosylation sites was mutated individually. By Western analysis of corin proteins in cell lysate and conditioned medium from transfected HEK293 cells and HL-1 cardiomyocytes, we found that N-glycosylation at Asn-80 inhibited corin shedding in the juxtamembrane domain. Similarly, N-glycosylation at Asn-231 protected corin from autocleavage in the frizzled-1 domain. Moreover, N-glycosylation at Asn-697 in the scavenger receptor domain and at Asn-1022 in the protease domain is important for corin cell surface targeting and zymogen activation. We also found that the location of the N-glycosylation site in the protease domain was not critical. N-Glycosylation at Asn-1022 may be switched to different sites to promote corin zymogen activation. Together, our results show that N-glycans at different sites may play distinct roles in regulating the cell membrane targeting, zymogen activation, and ectodomain shedding of corin.  相似文献   
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