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991.
Chunxiu Shen Zhiqun Que Yumei Xia Ning Tang Ding Li Ronghua He Mengliang Cao 《Journal of Plant Biology》2017,60(6):539-547
Plant annexins are Ca2+-dependent phospholipid-binding proteins and exist as multigene families in plants. They are implicated in the regulation of plant development as well as protection from environmental stresses. In this study, the rice annexin gene OsAnn3 knockout was performed via the CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/CRISPR associated proteins) mediated genome editing. Thus, mutant plantlets were successfully obtained. We identified cold tolerance phenotype of T1 mutant lines from T0 biallelic mutants using the 4~6°C for 3 days cold treatment. The results showed that REC (the relative electrical conductivity) of T1 mutant lines was increased, and the survival ratio of T1 mutant lines was decreased dramatically compared with the wild type after the exposure to cold treatment. It was suggested that OsAnn3 was involved in cold tolerance of rice. 相似文献
992.
993.
- The fast growth of mulberry depends on high water consumption, but considerable variations in drought tolerance exist across different cultivars. Physiological and anatomical mechanisms are important to plant survival under drought. However, few research efforts have been made to reveal the relationships of these two aspects in relation to drought tolerance.
- In this study, growth rates, leaf functional physiology and anatomical characteristics of leaf and xylem of 1‐year‐old saplings of seven mulberry cultivars at a common garden were compared. Their relationships were also explored.
- Growth, leaf physiology and anatomy were significantly different among the tested cultivars. Foliar stable carbon isotope composition (δ13C) was negatively correlated with growth rates, and closely related to several leaf and xylem anatomical traits. Particularly, leaf thickness, predicted hydraulic conductivity and vessel element length jointly contributed 77% of the variability in δ13C. Cultivar Wupu had small stomata, intermediate leaf thickness, the smallest hydraulically weighted vessel diameter and highest vessel number, and higher δ13C; Yunguo1 had high abaxial stomatal density, low specific leaf area, moderate hydraulic conductivity and δ13C; these are beneficial features to reduce leaf water loss and drought‐induced xylem embolism in arid areas. Cultivar Liaolu11 had contrasting physiological and anatomical traits compared with the previous two cultivars, suggesting that it might be sensitive to drought.
- Our findings indicate that growth and δ13C are closely associated with both leaf and xylem anatomical characteristics in mulberry, which provides fundamental information to assist evaluation of drought tolerance in mulberry cultivars and in other woody trees.
994.
Yu Du Zhao Yundi Pan Junhui Yang Xingmiao Liang Zhenjie Xie Shengda Cao Ruibing 《中国病毒学》2021,36(6):1443-1455
Virologica Sinica - The Japanese encephalitis serogroup of the neurogenic Flavivirus has a specific feature that expresses a non-structural protein NS1′ produced through a programmed -1... 相似文献
995.
Zhu Yun Xu Baoping Li Changchong Chen Zhimin Cao Ling Fu Zhou Shang Yunxiao Chen Aihuan Deng Li Bao Yixiao Sun Yun Ning Limin Yu Shuilian Gu Fang Liu Chunyan Yin Ju Shen Adong Xie Zhengde Shen Kunling 《中国病毒学》2021,36(6):1543-1553
Virologica Sinica - Community-acquired pneumonia (CAP) is one of the leading causes of morbidity and mortality in children worldwide. In this study, we aimed to describe the aetiology of viral... 相似文献
996.
997.
目的 探讨表没食子儿茶素没食子酸酯(EGCG)对高脂饮食大鼠脂肪组织中肿瘤坏死因子-α(TNF-α)表达的影响及其与胰岛素敏感性的相关性.方法 将30只SPF级雄性SD大鼠随机分为正常饮食组(ND组,n=10)和高脂饮食组(HFD组,n=20).喂养16w,当两组大鼠体质量出现显著差异后(P〈0.05),将HFD组按随机区组原则分为单纯高脂组(HFD组,n=10)和EGCG干预组(HFD+0.32%EGCG,EGCG组,n=10).干预16w.留取血清及附睾周脂肪组织.检测每组大鼠空腹血糖(FBG)、胰岛素水平(FINS)及游离脂肪酸(FFAs),并计算胰岛素抵抗指数(HOMA-IR);应用Real-time PCR及Western blot方法检测附睾周脂肪组织中TNF-α表达水平.结果 (1)与HFD组相比,EGCG组FINS水平显著下降[分别为(13.83±0.79)mIU/l vs.(31.71±3.61)mIU/l,P〈0.05];HOMA-IR值下降[分别为(3.36±0.31) vs.(7.59±0.99),P〈0.05];FFAs值亦明显下降[分别为(0.38±0.08)mmol/l vs.(0.81±0.11)mmol/l,P〈0.05];三组大鼠FBG水平无明显统计学差异(P〉0.05).(2)与ND组相比,HFD组脂肪组织中TNF-αmRNA水平显著升高[分别为(0.0033±0.00070)vs.(0.0010±0.00008),P〈0.01];而EGCG组较HFD组则明显下降[分别为(0.0018±0.00037)vs.(0.0033±0.00070),P〈0.05];同时,EGCG组TNF-α蛋白表达量低于HFD组[分别为(0.42±0.09)vs.(0.67±0.09),P〈0.05];(3)EGCG组与ND组无明显差异(P〉0.05).结论 EGCG改善高脂饮食大鼠胰岛素敏感性可能与减轻脂肪组织TNF-α介导的炎症状态相关. 相似文献
998.
999.
McNamara ME Briggs DE Orr PJ Noh H Cao H 《Proceedings. Biological sciences / The Royal Society》2012,279(1731):1114-1121
Structural colours, the most intense, reflective and pure colours in nature, are generated when light is scattered by complex nanostructures. Metallic structural colours are widespread among modern insects and can be preserved in their fossil counterparts, but it is unclear whether the colours have been altered during fossilization, and whether the absence of colours is always real. To resolve these issues, we investigated fossil beetles from five Cenozoic biotas. Metallic colours in these specimens are generated by an epicuticular multi-layer reflector; the fidelity of its preservation correlates with that of other key cuticular ultrastructures. Where these other ultrastructures are well preserved in non-metallic fossil specimens, we can infer that the original cuticle lacked a multi-layer reflector; its absence in the fossil is not a preservational artefact. Reconstructions of the original colours of the fossils based on the structure of the multi-layer reflector show that the preserved colours are offset systematically to longer wavelengths; this probably reflects alteration of the refractive index of the epicuticle during fossilization. These findings will allow the former presence, and original hue, of metallic structural colours to be identified in diverse fossil insects, thus providing critical evidence of the evolution of structural colour in this group. 相似文献
1000.
神农架川金丝猴栖息地森林群落的数量分类与排序 总被引:1,自引:0,他引:1
在神农架川金丝猴生境典型地段设立样方58块,根据样方资料对神农架川金丝猴栖息地的森林群落用组平均法分类和DCA排序.用组平均法将58块样地分为9个群系,依据《中国植被》的分类原则和系统将研究区植物群落划归为7个植被型.样地的DCA排序较好地揭示了该区森林群落的分布格局与环境梯度的关系;DCA第二轴明显地反映出森林群落的海拔梯度变化,沿DCA第二轴从右到左,海拔逐渐升高;第一轴表现了各植物群落或植物种所在环境的坡度、坡向,即水分和光照因素,沿第一轴从下到上,坡度渐缓、坡向渐向阳.其中海拔梯度是环境因子中对森林群落起决定性作用的因子.研究表明,巴山冷杉+糙皮桦-大齿槭+尾萼蔷薇-高原露珠草+星果草群系发育较好,高大树木占有较大的比例,是神农架川金丝猴最适宜栖息地.7个植被型物种丰富度指数在群落梯度上呈规律性波动.其中针叶林和针叶-阔叶混交林中,物种丰富度指数在群落梯度上的总体趋势表现为灌木层>草木层>乔木层;在常绿阔叶林和常绿-落叶阔叶混交林中,该趋势为灌木层>乔木层>草本层;在落叶阔叶林中,其丰富度指数的趋势为灌木层>草本层和乔木层.不同植被类型川金丝猴食源植物种类在群落梯度上的变化趋势与物种丰富度指数相同,但地衣类植物作为川金丝猴冬季的重要食物只在针叶林和针叶-阔叶混交林中生长.本研究为制定栖息地保护计划,更好地保护神农架川金丝猴提供了科学理论依据. 相似文献