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991.
生物多样性的稳定维持关乎人类生存发展与地球健康。生物多样性核心监测指标(Essential Biodiversity Variables, EBVs)旨在结合地面调查与遥感技术, 为大尺度、长时间序列的生物多样性监测提供新的解决方案。然而, 目前学界仍然缺乏一套国家尺度标准化EBVs遥感监测产品数据集, 以进行生物多样性评估。本研究旨在对中国生物多样性核心监测指标遥感产品进行体系构建与思考, 首先综述了目前EBVs的遥感研究概况, 并根据EBVs研究文献的数量进行调研分析; 同时, 本文在已有遥感生物多样性产品优先标准的基础上, 添加了“可重复性”的新标准, 并据此构建了中国EBVs遥感产品体系与监测数据集的指标清单, 最终对中国EBVs遥感研究存在的问题进行思考与讨论。本研究可为中国的生物多样性遥感监测提供科学依据, 有望为中国生物多样性政策的制定提供支撑。 相似文献
992.
MYB类转录因子在植物生长发育、代谢、应答生物胁迫和非生物胁迫的响应等生物过程发挥重要作用。为探究马尾松R2R3-MYB基因结构及功能,该研究以转录组数据为研究区域,从中筛选获得了17个马尾松R2R3-MYB基因,利用生物信息学对基因进行理化性质、系统进化树等分析,同时利用荧光定量PCR技术分析基因的组织特异性以及在花发育时期和非生物胁迫下的表达模式。结果表明:(1)17个PmMYBs亚细胞定位于细胞核,均无跨膜结构,且均含有Motif1、Motif2保守基序。系统发育进化树将马尾松PmMYBs划分为9个亚家族,且与火炬松、白云杉等裸子针叶植物关系较近。(2)17个基因均属于组成型表达,但在不同组织的表达量不同;所有基因均参与了花发育和非生物胁迫,不同基因在花发育不同时期的表达存在差异,有7个基因可能参与了雌雄性状转变;大部分基因响应非生物胁迫上调表达,但响应胁迫的时间存在差异;少数基因在胁迫中下调表达,尤其是PmMYB11基因在所有胁迫中均明显下调表达。该研究较系统地分析了马尾松R2R3-MYB基因的结构特征、系统进化及其在花发育时期和非生物胁迫下的表达模式,为深入探究马尾松R2R3... 相似文献
993.
Highlights
1. The structure of glycoprotein Gc, responsible for mediating membrane fusion between cell and CCHFV, is revealed, but many more mysteries remain.
2. Why do only antibodies against Gc have neutralizing effect, but not the one against Gn?
3. Why can NAbs against Gc only be protective in the animals in preventive settings, but not in the therapeutic administration? 相似文献
1. The structure of glycoprotein Gc, responsible for mediating membrane fusion between cell and CCHFV, is revealed, but many more mysteries remain.
2. Why do only antibodies against Gc have neutralizing effect, but not the one against Gn?
3. Why can NAbs against Gc only be protective in the animals in preventive settings, but not in the therapeutic administration? 相似文献
994.
Griphin Ochieng Ochola Bei Li Vincent Obanda Sheila Ommeh Harold Ochieng Xing-Lou Yang Samson Omondi Onyuok Zheng-Li Shi Bernard Agwanda Ben Hu 《中国病毒学》2022,37(4):491-502
Emergence and re-emergence of infectious diseases of wildlife origin have led pre-emptive pathogen surveillances in animals to be a public health priority. Rodents and shrews are among the most numerically abundant vertebrate taxa and are known as natural hosts of important zoonotic viruses. Many surveillance programs focused more on RNA viruses. In comparison, much less is known about DNA viruses harbored by these small mammals. To fill this knowledge gap, tissue specimens of 232 animals including 226 rodents, five shrews and one hedgehog were collected from 5 counties in Kenya and tested for the presence of DNA viruses belonging to 7 viral families by PCR. Diverse DNA sequences of adenoviruses, adeno-associated viruses, herpesviruses and polyomaviruses were detected. Phylogenetic analyses revealed that most of these viruses showed distinction from previously described viruses and formed new clusters. Furthermore, this is the first report of the discovery and full-length genome characterization of a polyomavirus in Lemniscomys species. This novel polyomavirus, named LsPyV KY187, has less than 60% amino acid sequence identity to the most related Glis glis polyomavirus 1 and Sciurus carolinensis polyomavirus 1 in both large and small T-antigen proteins and thus can be putatively allocated to a novel species within Betapolyomavirus. Our findings help us better understand the genetic diversity of DNA viruses in rodent and shrew populations in Kenya and provide new insights into the evolution of those DNA viruses in their small mammal reservoirs. It demonstrates the necessity of ongoing pathogen discovery studies targeting rodent-borne viruses in East Africa. 相似文献
995.
Ge Gao Xue Hu Yiwu Zhou Juhong Rao Xiaoyu Zhang Yun Peng Jiaxuan Zhao Yanfeng Yao Kunpeng Liu Mengying Liang Hang Liu Fei Deng Han Xia Chao Shan Zhiming Yuan 《中国病毒学》2022,37(2):299-302
Highlights
1. Delta variant of SARS-CoV-2 can effectively infect the Rhesus macaque.
2. The Delta variant grows faster than the early strain isolated from Wuhan in late 2019.
3. The shedding pattern, viral load and disease severity of Delta variant are similar with the early strain isolated from Wuhan in late 2019.
4. This study supports the attributed rapid disease spread of the Delta variant. 相似文献
1. Delta variant of SARS-CoV-2 can effectively infect the Rhesus macaque.
2. The Delta variant grows faster than the early strain isolated from Wuhan in late 2019.
3. The shedding pattern, viral load and disease severity of Delta variant are similar with the early strain isolated from Wuhan in late 2019.
4. This study supports the attributed rapid disease spread of the Delta variant. 相似文献
996.
Xin‐Sheng Hu Xin‐Xin Zhang Wei Zhou Ying Hu Xi Wang Xiao‐Yang Chen 《Evolution; international journal of organic evolution》2019,73(2):158-174
Understanding the ecological and evolutionary mechanisms that shape a species’ range is an important goal in evolutionary biology. Evidence indicates that mating system is an effective predictor of the global range of native species or naturalized alien plants, but the mechanisms underlying this predictability are not elaborated. Here, we develop a theoretical model to account for the ranges of plants under different mating systems based on migration‐selection processes (an idea proposed by Haldane). The model includes alternation of gametophyte and sporophyte generations in one life cycle and the dispersal of haploid pollen and diploid seeds as vectors for gene flow. We show that the interaction between selfing rates and gametophytic selection determines the role of mating system in shaping a species’ range. Selfing restricts the species’ range under gametophytic selection in nonrandom mating systems, but expands the species’ range under the absence of gametophytic selection in any mating system. Gametophytic selection slightly restricts the species’ range in random mating. Both logarithmic and logistic models of population demography yield similar conclusions in the case of fixed or evolving genetic variance. The theory also helps to explain a broader relationship between mating system and range size following biological invasion or plant naturalization. 相似文献
997.
Na Wan Zhe Xu Qianru Chi Xueyuan Hu TingRu Pan Tianqi Liu Shu Li 《Journal of cellular physiology》2019,234(8):13693-13704
Selenium (Se) deficiency induces typical clinical and pathological changes and causes various pathological responses at the molecular level in several different chicken organs; the kidney is one of the target organs of Se deficiency. To explore the mechanisms that underlie the effects of microRNA-33-3p (miR-33-3p) on Se deficiency-induced kidney apoptosis, 60 chickens were randomly divided into two groups (30 chickens per group). We found that Se deficiency increased the expression of miR-33-3p in the chicken kidney. A disintegrin and metalloprotease domain 10 (ADAM10) was verified to be a target of miR-33-3p in the chicken kidney. The overexpression of miR-33-3p decreased the expression levels of β-catenin, cyclinD1, T-cell factor (TCF), c-myc, survivin, and Bcl-2; it increased the expression levels of E-cadherin, Bak, Bax, and caspase-3; and it increased the number of chicken kidney cells in the G0/G1 phase. In addition, Se deficiency caused the ultrastructure of the kidney to develop apoptotic characteristics. The results of flow cytometry analysis and AO/EB staining showed that the number of apoptotic chicken kidney cells increased in the miR-33-3p mimic group. All these results suggest that Se deficiency-induced cell cycle arrest and apoptosis in vivo and in vitro in the chicken kidney via the regulation of miR-33-3p, which targets ADAM10. 相似文献
998.
999.
Bin Shen Ningfeng Zhou Tao Hu Weidong Zhao Desheng Wu Shanjin Wang 《Journal of cellular physiology》2019,234(8):13464-13480
This study was aimed to figure out whether long noncoding RNA MEG3/miR-361-5p/FoxM1 signaling would contribute to improved proliferation and metastasis of osteosarcoma cells. We altogether collected 204 pairs of osteosarcoma tissues and adjacent normal tissues, and obtained four human osteosarcoma cell lines. Then pcDNA3.1-MEG3, si-MEG3, miR-361-5p mimic, miR-361-5p inhibitor, pcDNA3.1-FoxM1, si-FoxM1, and negative control (NC) were, respectively, transfected into the osteosarcoma cells. Furthermore, real time polymerase chain reaction was utilized to determine the mRNA expressions of maternally expressed gene 3 (MEG3) and miR-361-5p, and western blot analysis was applied for determining the FoxM1 expression. Besides, dual luciferase reporter gene assay was adopted to verify if MEG3 can be directly targeted by miR-361-5p. Finally, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide, colony formation assay, flow cytometry, wound healing assay, and transwell assay were conducted to investigate the influence of MEG3, miR-361-5p, and FoxM1 expressions on the viability, proliferation, apoptosis, migration, and invasion of osteosarcoma cells. MEG3 and miR-361-5p were observed to be significantly downregulated within both osteosarcoma tissues and cell lines, whereas FoxM1 was upregulated in osteosarcoma tissues and cell lines (p < 0.05). MEG3 directly bound to miR-361-5p, and significantly upgraded its expression (p < 0.05). The upregulated MEG3 and miR-361-5p or the downregulated FoxM1 appeared to substantially inhibit proliferation, migration, and invasion of osteosarcoma cells (p < 0.05). Finally, the proliferation, migration, invasion, and motility of osteosarcoma cells within the miR-NC + pcDNA3.1-FoxM1 group and pcDNA + pcDNA-FoxM1 group were markedly promoted when compared with the miR-361-5p mimic group and pcDNA3.1-MEG3 group (p < 0.05). The MEG3/miR-361-5p/FoxM1 axis could potentially serve as therapeutic targets or diagnostic biomarkers for osteosarcoma. 相似文献
1000.
Xumin Hu Jianhua Tang Gang Zeng Xuyun Hu Peng Bao Jionglin Wu Yuwei Liang Weixi Deng Yong Tang 《Journal of cellular physiology》2019,234(11):20432-20442
Emerging evidence shows that rheumatoid arthritis (RA) progression can be induced by the activation of Toll-like receptor (TLR) signaling pathway. Regulator of G-protein signaling 1 (RGS1) is observed to be a candidate biomarker for arthritis. Accordingly, the present study aims to determine the potential effects of RGS1 mediating TLR on RA. A rat model of collagen-induced arthritis (CIA) was established to mimic the features of RA by injection of bovine type II collagen. The rats with CIA were treated with short hairpin RNA (shRNA) against RGS1 or TLR pathway activator Poly I:C to elucidate the role of RGS1 in RA progression. The inflammatory factors were measured, and the thoracic gland and spleen indexes as well as the vascular density were determined. The expression levels of RGS1, TLR3, vascular endothelial growth factor (VEGF), metalloproteinase-2 (MMP-2), MMP-9, and interleukin 1 receptor-associated kinase-4 (IRAK4) were determined. RGS1 was robustly increased in RA. The TLR signaling pathway was suppressed by RGS1 silencing. shRNA-mediated depletion of RGS1 was shown to significantly enhance thoracic gland index and inhibit the serum levels of TNF-α, IL-1β, and IL-17, spleen index, vascular density, and the expression levels of TLR3, VEGF, MMP-2, MMP-9, and IRAK4. However, when the rats with CIA were treated with Poly I:C, the trend of effects was opposite. These findings highlight that functional suppression of RGS1 inhibits the inflammatory response and angiogenesis by inactivating the TLR signaling pathway in rats with CIA, thereby providing a novel therapeutic target for RA treatment. 相似文献