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951.
厦门同安湾定置网捕获鱼类的多样性及营养级特征 总被引:1,自引:0,他引:1
利用2012年4月至2013年3月在同安湾进行的定置网渔业资源调查资料, 探讨了该海域鱼类多样性及平均营养级特征。结果表明, 周年逐月共鉴定鱼类112种, 隶属于15目53科88属。渔获物组成以沿岸小型底层鱼类为主, 其中中上层鱼类15种, 中下层鱼类18种, 底层鱼类79种; 暖水性种类84种, 暖温性种类28种, 亚热带动物区系特征明显; 杂食性鱼类8种, 低级肉食性鱼类71种, 中级肉食性鱼类30种, 高级肉食性鱼类3种, 以低级肉食性鱼类为主。中华海鲶(Tachysurus sinensis)是夏、秋、冬三季的优势种, 六指多指马鲅(Polydactylus sextarius)、锯脊塘鳢(Butis koilomatodon)和髭缟鰕虎鱼(Tridentiger barbatus)是春、冬两季的优势种。重量和尾数多样性指数最高值均在11月, 分别为3.26和3.29; 最低值均在2月, 分别为1.78和1.77。鱼类种类存在明显的季节更替现象, 其月更替率6月最低, 为40.1%; 3月最高, 达68.6%。鱼类平均营养级也存在明显的季节变化, 其中3月最低, 为3.02; 1月最高, 为3.92; 周年平均营养级为3.52。与2003年调查资料相比, 鱼类种类数明显减少, 鱼类组成和优势种发生了很大的变化, 导致变化的主要原因可能是过度捕捞、栖息地破坏和环境污染等。 相似文献
952.
953.
Role of aquaporin water channels in pleural fluid dynamics 总被引:16,自引:0,他引:16
Song Y Yang B Matthay MA Ma T Verkman AS 《American journal of physiology. Cell physiology》2000,279(6):C1744-C1750
954.
955.
应用Y染色体多态标记对汉族王姓亲缘关系的研究 总被引:2,自引:0,他引:2
Y染色体除拟常染色体区外 ,其它区域均缺乏重组 ,因而可保留其祖先历史上所发生的突变事件。作为研究父系遗传的工具 ,Y染色体多态具有独特的作用。中国传统上姓氏由父亲传给子女 ,遵循父系传递。本实验应用 Y染色体的 4个微卫星标记 (即 DYS1 9、DYS390、DYS391和 YCA2 ) ,对 50例北京汉族王姓男性 DNA样本进行了多态性分析 ,并与本实验室对 50例汉族男性随机样本应用前 3个位点检测的结果相比较 ,结果表明 :北京汉族王姓男性携带的 Y染色体单体型与对照无差异。王姓有复杂的多起源可能可以解释这一结果。 相似文献
956.
Characterization of a G protein α subunit encoded gene from the dimorphic fungus-Tremella fuciformis
Zhu Hanyu Liu Dongmei Zheng Liesheng Chen Liguo Ma Aimin 《Antonie van Leeuwenhoek》2021,114(11):1949-1960
Antonie van Leeuwenhoek - Tremella fuciformis is a dimorphic fungus which can undertake the reversible transition between yeast and pseudohypha forms. G protein α subunit (Gα) carries... 相似文献
957.
958.
Lian-Kun Song Kai-Li Ma Yu-He Yuan Zheng Mu Xiu-Yun Song Fei Niu Ning Han Nai-Hong Chen 《PloS one》2015,10(6)
Mutations, duplication and triplication of α-synuclein genes are linked to familial Parkinson’s disease (PD), and aggregation of α-synuclein (α-syn) in Lewy bodies (LB) is involved in the pathogenesis of the disease. The targeted overexpression of α-syn in the substantia nigra (SN) mediated by viral vectors may provide a better alternative to recapitulate the neurodegenerative features of PD. Therefore, we overexpressed human wild-type α-syn using rAAV2/1 vectors in the bilateral SN of mouse and examined the effects for up to 12 weeks. Delivery of rAAV-2/1-α-syn caused significant nigrostriatal degeneration including appearance of dystrophic striatal neurites, loss of nigral dopaminergic (DA) neurons and dissolving nigral neuron bodies in a time-dependent manner. In addition, the α-syn overexpressed mice also developed significant deficits in motor function at 12 weeks when the loss of DA neurons exceeded a threshold of 50%. To investigate the sensitivity to neurotoxins in mice overexpressing α-syn, we performed an MPTP treatment with the subacute regimen 8 weeks after rAAV injection. The impact of the combined genetic and environmental insults on DA neuronal loss, striatal dopamine depletion, dopamine turnover and motor dysfunction was markedly greater than that of either alone. Moreover, we observed increased phosphorylation (S129), accumulation and nuclear distribution of α-syn after the combined insults. In summary, these results reveal that the overexpressed α-syn induces progressive nigrostriatal degeneration and increases the susceptibility of DA neurons to MPTP. Therefore, the targeted overexpression of α-syn and the combination with environmental toxins may provide valuable models for understanding PD pathogenesis and developing related therapies. 相似文献
959.
Fen Liu Yi-Ning Yang Xiang Xie Xiao-Mei Li Xiang Ma Zhen-Yan Fu Bang-Dang Chen Ying Huang Chun-Fang Shan Yi-Tong Ma Xiao-Ming Gao 《PloS one》2015,10(8)
Background
The prevalence and risk factors of congenital heart disease among Xinjiang, northwestern part of China is currently unknown.Methods
This multiple-ethnic, community-based, cross-sectional study was conducted to estimate the prevalence and distribution of congenital heart disease (CHD) in Xinjiang, northwestern part of China. Four major ethnics, Uygur, Han, Kazak, and Hui children in this region were investigated during February 2010 and May 2012.Results
A total of 14,530 children (0–18 yr) were examined. Of these children, 240 (boys, 43.8%, and girls, 56.3%) were identified with CHD, giving an overall prevalence of 16.5‰ (17.7‰ in Uygur, 6.9‰ in Han, 11.4‰ in Kazak, and 38.1‰ in Hui Chinese, respectively). Ventricular septal defect (VSD, 29.2%), atrial septal defect (ASD, 20.8%), patent ductus arteriosus (PDA, 13.7%), acleistocardia (13.7%), Bicuspid aortic valve (7.9%), pulmonary valve stenosis (5.4%), and tetralogy of fallot (TOF, 4.2%) were common cyanotic and cyanotic defects observed. Compared to non-CHD children, children with CHD had a higher percentage of history of abortion, CHD history of family, consanguinity and premature birth (all P<0.05). In CHD children, 24% of mothers caught a cold, 10% had a febrile illness and 6.7% received antibiotic treatment during the first trimester of pregnancy, that were higher than non-CHD group (all P<0.05).Conclusion
The overall prevalence of CHD in four ethnic children at ages 0–18 yr in Xinjiang was 16.5‰. VSD, ASD and TOF were the most common acyanotic and cyanotic congenital heart defects, respectively. This study also identified some modifiable risk factors that may contribute to the incidence of CHD among the 4 ethnic groups. 相似文献960.
Xinfeng Tang Fahui Yang Tan Tang Xuemei Yang Weijun Zhang Xiaohua Wang Li Ji Yun Xiao Kun Ma Ying Wang Xianglei Kong Jianping Wang Jun Liu Qian Xu Donghua Tian Zhiyong Qu 《PloS one》2015,10(9)