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The seasonal variations in phytoplankton community structure were investigated for the Sanggou Bay (SGB) and the adjacent Ailian Bay (ALB) and Lidao Bay (LDB) in Shandong Peninsula,eastern China.The species composition and cell abundance of phytoplankton in the bay waters in spring (April 2011),summer (August 2011),autumn (October 2011),and winter (January 2012) were examined using the Uterm6hl method.A total of 80 taxa of phytoplankton that belong to 39 genera of 3 phyla were identified.These included 64 species of 30 genera in the Phylum Bacillariophyta,13 species of 8 genera in the Phylum Dinophyta,and 3 species of 1 genus in the Phylum Chrysophyta.During the four seasons,the number of phytoplankton species (43) was the highest in spring,followed by summer and autumn (40),and the lowest number ofphytoplankton species (35) was found in winter.Diatoms,especially Paralia sulcata (Ehrenberg) Cleve and Coscinodiscus oculus-iridis Ehrenberg,were predominant in the phytoplankton community throughout the study period,whereas the dominance of dinoflagellate appeared in summer only.The maximum cell abundance of phytoplankton was detected in summer (average 8.08 × 103 cells L-1) whereas their minimum abundance was found in autumn (average 2.60 x 103 cellsL-1).The phytoplankton abundance was generally higher in the outer bay than in the inner bay in spring and autumn.In summer,the phytoplankton cells were mainly concentrated in the south of inner SGB,with peak abundance observed along the western coast.In winter,the distribution of phytoplankton cells showed 3 patches,with peak abundance along the western coast as well.On seasonal average,the Shannon-Wiener diversity indices of phytoplankton community ranged from 1.17 to 1.78 (autumn 〉 summer 〉 spring 〉 winter),and the Pielou's evenness indices of phytoplankton ranged from 0.45 to 0.65 (autumn 〉 spring 〉 summer〉 winter).According to the results of canonical correspondence analysis,phosphate level w 相似文献
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Planktonic copepod Calanus sinicus is the dominant meso-zooplankton in the Northwest Pacific Ocean. To better understand its population dynamics and phylogeographic patterns, 243 C. sinicus individuals were collected from seven locations across the shelf waters of China and its population genetics was studied by mitochondrial DNA cytochrome oxidase I(mtCOI) sequences analyses. Thirty-nine different sequences, or haplotypes, were detected with moderate haplotype diversity(h=0.749) and low nucleotide diversity(π=0.003) for all populations. The evolutionary divergence between geographic populations varied from 0.24% to 0.37%, indicative of very limited genetic differentiation. Visualized minimum spanning network(MSN) and phylogenetic analysis of all the detected haplotypes did not reveal any clear phylogeographic pattern. Furthermore, AMOVA data showed no significant spatial population differentiation existed among the individuals collected across China shelf waters. Pairwise FST values showed that population collected from northwest of the East China Sea(ECS) displayed a low difference to other populations. Mismatch distribution analyses and neutrality tests indicated that C. sinicus might undergo a demographic/population expansion. No significant population genetic structuring was detected, indicating an extensive gene flow among the C. sinicus populations. Our results provide molecular evidence for the hypothesis that C. sinicus in the northwestern South China Sea in winter is transported from the East China Sea and the Yellow Sea by the China Coastal Current during the northeast monsoon period. 相似文献
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褐藻多糖硫酸酯对脂多糖诱导大鼠肾小球系膜细胞NO产生量的影响 总被引:2,自引:2,他引:0
慢性肾衰的进程中伴随着肾脏炎症的发生,研究表明褐藻多糖硫酸酯具有抗炎作用,且对于慢性肾衰的早期治疗具有一定的作用。本文通过脂多糖(lipopolysaccharide,LPS)诱导,建立大鼠肾小球系膜细胞的炎症模型,用来源于海带的高分子质量褐藻多糖硫酸酯F1和低分子质量褐藻多糖硫酸酯F2对细胞进行处理,24 h后MTT法检测各组细胞活力,Griess法检测24 h及48 h后细胞培养液中NO的含量。结果表明,各组间细胞活力无明显差异;脂多糖可以诱导大鼠肾小球系膜细胞NO产量增加,F1和F2均可在一定程度上抑制脂多糖诱导的NO产量的增加,从而减轻细胞炎症反应。剂量为25μg/m L的F1和F2处理细胞48 h后,与模型组相比,F1和F2组细胞培养液中NO含量分别下降22.52%和38.65%,低分子质量褐藻多糖硫酸酯抗炎效果明显高于高分子质量褐藻多糖硫酸酯。 相似文献
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The annual life cycle of the brown seaweed Undaria pinnatifi da(Harvey)Suringer comprises a macroscopic diploid sporophyte stage and a microscopic haploid gametophyte stage.In 2011,an unusual zoospore-derived monoecious gametophyte isolate(designated as line 10-5-3)of U.pinnatifi da was observed.To understand this phenomenon,a comprehensive screening of eighty-two previously identifi ed male gametophyte cultures,isolated from three randomly selected cultivars(lines 10,7,and 5)was performed.Thirty-six of the isolates developed both antheridia and oogonia on the same fi lamentous fragment in a standard gametogenesis test(SGT: 18°C,60 μmol photons/(m 2·s)).Selfi ng of the monoecious gametophyte or crossing it with a normal male gametophyte both gave rise to morphologically normal sporophytic offspring.However,crossing resulted in a much higher fertilization rate(89.7%).The hybrid and selfed sporophytic offspring were grown to maturity in fl ow tanks at an ambient temperature of 10–18°C over a period of 69 days.Active zoospores were released from both types of mature sporophylls.The majority of these developed into male gametophytes,while 15%–20% developed into the observed monoecious structures on the same fi lament.Using PCR amplifi cation it was found that all the monoecious gametophyte isolates and the sporophytic offspring resulting from the selfi ng and crossing lacked the femalelinked microsatellite sequence(a part of the locus Up-AC-2A8,GenBank accession No.AY738602.1),indicating their male nature.U.pinnatifi da is an invasive species in some regions and the implications of the above fi ndings for this species in nature are briefl y discussed. 相似文献
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6-O-羧甲基壳多糖的细胞毒性效应研究 总被引:5,自引:0,他引:5
Chen Xiguang 《中国海洋大学学报(自然科学版)》2000,30(Z1):221-224
采用溶血试验和细胞毒性试验研究6 -O-羧甲基壳多糖的细胞毒性效应,结果表明:1% 浓度的6-O-羧甲基壳多糖对红细胞溶 血率小于5%,说明该材料无溶血现象。以手术缝合线和500μg/mL的苯酚为对照研究不同分 子量的6-O-羧甲基壳多糖分别在1000μg/mL和2000μg/mL浓度下对大白鼠皮肤成纤维细胞 生长的影响,经过2d,4d,7d细胞培养,细胞增殖率均大于100%,说明该材料对成纤维细胞 无毒性效应且对大白鼠皮肤成纤维细胞有促进生长的作用,分子量越小促生长作用越强,随 着培养时间延长促生长作用亦增强。此研究在一定程度上证明,6-O-羧甲基壳多糖作为医 用生物材料在细胞毒性方面是安全的。 相似文献
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目的:基于网络药理学方法研究败酱草抗非小细胞肺癌(NSCLC)的主要活性成分及其作用靶点,探讨其作用机制。方法:通过TCMSP数据库查询败酱草的有效成分及作用靶点,将口服生物利用度(OB)≥30%和类药性(DL)≥0.18作为筛选标准。运用GeneCards数据库搜索NSCLC的作用靶点,将两者基因取交集,在Cytoscape 3.8.2软件导入共同基因,构建药物-活性成分-作用靶点网络图。基于STRING数据库构建蛋白质-蛋白质相互作用(PPI)网络,导入Cytoscape 3.8.2软件进行网络可视化分析。运用Metascape数据库对药物靶点进行基因本体(GO)功能和京都基因与基因组百科全书(KEGG)通路富集分析。结果:败酱草作用于NSCLC的有效活性成分共11种,作用靶点有87个,包括肿瘤P53蛋白(TP53)、丝氨酸/苏氨酸蛋白激酶(AKT1)、原癌基因蛋白(MYC)、半胱天冬酶3(CASP3)、G1/S特异性细胞周期蛋白D1(CCND1)等基因;作用的信号通路主要集中在癌症的途径、白细胞介素-17(IL-17)信号通路、人类疱疹病毒(Epstein-Barr病毒)感染、癌症中的蛋白多糖等。结论:败酱草对NSCLC的作用机制可能通过TP53、AKT1、MYC、CASP3、CCND1等关键蛋白起作用。 相似文献