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991.
黑色素瘤作为一种多发于皮肤部位的恶性肿瘤,严重危害着动物和人们的健康。与传统抗体比较,单域抗体具有结构简单、分子量小、免疫原性弱等特点,使其在疾病的诊断及治疗方面具有广阔的应用空间。本研究以B16-F10细胞蛋白质为研究对象,通过反复冻融与超声破碎相结合的方式获得B16-F10蛋白质作为抗原,免疫成年雄性羊驼。采用噬菌体单域抗体展示技术,构建了质量优良的B16-F10细胞蛋白质单域抗体免疫文库,其库容为5.76 × 1010,VHH重组率为96%,文库丰度为3.00 × 1010个/mL。该结果为研究黑色素瘤的生物学特性提供了新思路,同时也为后续筛选B16-F10单域抗体奠定了基础。  相似文献   
992.
We previously demonstrated that pre‐conditioning with CpG oligonucleotide (ODN) 1668 induces quick up‐regulation of gene expression 3 hours post‐murine myocardial ischaemia/reperfusion (I/R) injury, terminating inflammatory processes that sustain I/R injury. Now, performing comprehensive microarray and biocomputational analyses, we sought to further enlighten the “black box” beyond these first 3 hours. C57BL/6 mice were pretreated with either CpG 1668 or with control ODN 1612, respectively. Sixteen hours later, myocardial ischaemia was induced for 1 hour in a closed‐chest model, followed by reperfusion for 24 hours. RNA was extracted from hearts, and labelled cDNA was hybridized to gene microarrays. Data analysis was performed with BRB ArrayTools and Ingenuity Pathway Analysis. Functional groups mediating restoration of cellular integrity were among the top up‐regulated categories. Genes known to influence cardiomyocyte survival were strongly induced 24 hours post‐I/R. In contrast, proinflammatory pathways were down‐regulated. Interleukin‐10, an upstream regulator, suppressed specifically selected proinflammatory target genes at 24 hours compared to 3 hours post‐I/R. The IL1 complex is supposed to be one regulator of a network increasing cardiovascular angiogenesis. The up‐regulation of numerous protective pathways and the suppression of proinflammatory activity are supposed to be the genetic correlate of the cardioprotective effects of CpG 1668 pre‐conditioning.  相似文献   
993.
To investigate the potential beneficial effect of insulin‐like growth factor‐1 (IGF‐1) in BMSC transplantation therapy of uterus injury and the underlying molecular mechanisms, rat BMSCs were isolated and cultured. The relative expressions of IGF‐1 and IL‐10 were determined by RT‐PCR and immunoblotting. The secretory IL‐10 and released E2 were measured using ELISA kits. The relative vWF and α‐SMA expressions were determined by immunohistochemistry. The direct binding of NF‐κB subunit p50 with IL‐10 promoter was analysed by chromatin immunoprecipitation assay. The regulation of IL‐10 expression by p50 was interrogated by luciferase reporter assay. Our data demonstrated that IGF‐1 expression in BMSCs induced IL‐10 expression and secretion, which was further enhanced by E2‐PLGA. IGF‐1 overexpression improved BMSCs transplantation therapy in rat uterus injury. We further demonstrated that both inhibition and knockdown of p50 abolished IGF‐1‐induced expression and secretion of IL‐10 in BMSCs, which consequently compromised the IGF‐1 conferred therapeutic benefits against uterus injury. Furthermore, we elucidated that p50 regulated IL‐10 expression via direct association with its promoter. Our data suggested that transplantation of IGF‐1 overexpressing BMSCs improved functional regeneration of injured uterus by inducing IL‐10 expression and secretion via activation of NF‐κB signalling.  相似文献   
994.
In vitiligo, cutaneous depigmentation is accompanied by increased T cell cytolytic activity targeting melanocytes, indicating that autoimmune tolerance is disrupted. The inhibited amount and function of Tregs have been indicated to be involved in the autoimmune intolerance in vitiligo, however, with the conclusion still controversial and the involved mechanism unknown. In this study, we explored the molecular and cellular alterations accounting for the impaired Treg response in vitiligo. Our results showed that the amount of Tregs was drastically reduced in peripheral blood of active vitiligo patients. Furthermore, the immunoregulatory function of Tregs was attenuated, with lower expression of CTLA4, IL‐10 and TGF‐β. Moreover, the expression of HO‐1, a functional modulator of Tregs, was decreased in vitiligo Tregs, and the concentrations of HO‐1 metabolites, including bilirubin, CoHb and iron, were correspondingly decreased in serum of vitiligo patients. In addition, we treated the Tregs from vitiligo patients with Hemin, an agonist of HO‐1, and found that enhanced HO‐1 expression restored the function of Tregs by up‐regulating IL‐10 expression. Our study demonstrates the essential role of HO‐1 in the impaired Treg response in vitiligo and indicates the potential of HO‐1 as a therapeutic target in vitiligo management.  相似文献   
995.
996.
Traits‐based approaches in microbial ecology provide a valuable way to abstract organismal interaction with the environment and to generate hypotheses about community function. Using macromolecular rate theory (MMRT), we recently identified that temperature sensitivity can be characterized as a distinct microbial trait. As temperature is fundamental in controlling biological reactions, variation in temperature sensitivity across communities, organisms, and processes has the potential to vastly improve understanding of microbial response to climate change. These microbial temperature sensitivity traits include the heat capacity (), temperature optimum (Topt), and point of maximum temperature sensitivity (TSmax), each of which provide unique insights about organismal response to changes in temperature. In this meta‐analysis, we analyzed the distribution of these temperature sensitivity traits from bacteria, fungi, and mixed communities across a variety of biological systems (e.g., soils, oceans, foods, wastewater treatment plants) in order to identify commonalities in temperature responses across these diverse organisms and reaction rates. Our analysis of temperature sensitivity traits from over 350 temperature response curves reveals a wide distribution of temperature sensitivity traits, with Topt and TSmax well within biological relevant temperatures. We find that traits vary significantly depending on organism type, microbial diversity, source environment, and biological process, with higher temperature sensitivity found in fungi than bacteria and in less diverse systems. Carbon dioxide production was found to be less temperature sensitive than denitrification, suggesting that changes in temperature will have a potentially larger impact on nitrogen‐related processes. As climate changes, these results have important implications for basic understanding of the temperature sensitivity of biological reactions and for ecological understanding of species’ trait distributions, as well as for improved treatment of temperature sensitivity in models.  相似文献   
997.
Microorganisms dominate the decomposition of organic matter and their activities are strongly influenced by temperature. As the carbon (C) flux from soil to the atmosphere due to microbial activity is substantial, understanding temperature relationships of microbial processes is critical. It has been shown that microbial temperature relationships in soil correlate with the climate, and microorganisms in field experiments become more warm‐tolerant in response to chronic warming. It is also known that microbial temperature relationships reflect the seasons in aquatic ecosystems, but to date this has not been investigated in soil. Although climate change predictions suggest that temperatures will be mostly affected during winter in temperate ecosystems, no assessments exist of the responses of microbial temperature relationships to winter warming. We investigated the responses of the temperature relationships of bacterial growth, fungal growth, and respiration in a temperate grassland to seasonal change, and to 2 years’ winter warming. The warming treatments increased winter soil temperatures by 5–6°C, corresponding to 3°C warming of the mean annual temperature. Microbial temperature relationships and temperature sensitivities (Q10) could be accurately established, but did not respond to winter warming or to seasonal temperature change, despite significant shifts in the microbial community structure. The lack of response to winter warming that we demonstrate, and the strong response to chronic warming treatments previously shown, together suggest that it is the peak annual soil temperature that influences the microbial temperature relationships, and that temperatures during colder seasons will have little impact. Thus, mean annual temperatures are poor predictors for microbial temperature relationships. Instead, the intensity of summer heat‐spells in temperate systems is likely to shape the microbial temperature relationships that govern the soil‐atmosphere C exchange.  相似文献   
998.
The present study aimed to investigate the perturbations in immuno-metabolic and redox status of buffaloes with trypanosomosis. Thirteen buffaloes suffering from clinical trypanosomosis and eight apparently healthy buffaloes were included in the present study. Buffaloes with trypanosomosis found to have markedly elevated levels of interleukin-10 (IL-10), nonesterified fatty acids (NEFA) and beta-hydroxybutyrate (BHBA) in comparison with healthy controls. Whereas, total antioxidant capacity (TAC) and haemoglobin levels of buffaloes with trypanosomosis were significantly lower than the healthy controls. Remarkable elevation in malondialdehyde (MDA) and protein carbonyls (PC) levels were also observed in the diseased buffaloes. Moreover, buffaloes with trypanosomosis were found to have markedly elevated levels of serum glucose, total proteins, globulins, urea and aspartate aminotransferase (AST) and markedly lowered levels of serum calcium, total cholesterol levels and albumin/globulin (A/G) ratio as compared to the controls. Findings of our study evidently suggest that Trypanosoma evansi induces remarkable immunosuppressive and pro-oxidative status with an increased catabolic activity and hyperglycemic condition like type-2 diabetes in naturally infected buffaloes. Therefore, immuno-metabolic and pro-oxidative predicaments should be addressed by the veterinary clinician while managing the clinical cases of trypanosomosis in buffaloes.  相似文献   
999.
1000.
The aim of this study is to survey the PM10, PM2.5, and PM1 concentrations in rural and urban areas in Tehran province during cold, warm and dust storm days from December 22, 2016 to June 5, 2017 using Grimm Model aerosol spectrometer. During the study period, daily PM10, PM2.5, and PM1 concentrations ranged from 27.2 to 244.96, 8.4 to 77.9, and 6.5 to 56.8 μg/m3 in urban sites, and 22.8 to 286.4, 6 to 41.1, and 2.1 to 20.2 μg/m3 in rural parts, respectively. Particularly, both daily WHO limits for outdoor PM10 (50.0 μg/m3) and PM2.5 (25.0 μg/m3) exceeded in 95% and 83% of the outdoor measurements in winter and 82% and 58% in total sampled days in urban site, respectively. The 24-h average PM10 and PM2.5 concentrations also exceeded by 59% and 18% in winter and by 36% and 14% of all sampling days in rural site, respectively. During the dust storm, the 24-h average PM10, PM2.5, and PM1 concentrations were, respectively 4.7, 2, and 1.96 times higher than those in urban site and 2, 1.7, and 1.3 times more than those in rural site in all sampled days.  相似文献   
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