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841.
目的:比较沙库巴曲缬沙坦与缬沙坦在慢性心力衰竭(Chronic heart failure, CHF)患者治疗中对心功能及肾功能的影响。方法:按WHO诊断标准随机选择CHF患者,对照组30例,给予缬沙坦80 mg/qd起,2-4周后增至160 mg/qd;研究组30例,给予沙库巴曲缬沙坦100 mg/bid,2-4周后增至200 mg/bid。治疗8周后,比较两组治疗后LVEF、LVESD和LVEDD的变化,以及对Scr、Cys C的影响。结果:(1)两组患者的性别、年龄、NYHA心功能分级等一般情况,以及治疗前LVEF、LVESD、LVEDD、Scr、Cys C等指标比较均无显著性差异(P0.05),具有可比性。(2)治疗8周后,对照组的LVEF较治疗前显著升高(38.87±6.95%VS.34.73±7.89%,P0.05),LVESD、LVEDD均较治疗前显著降低(44.43±8.26 mm VS.50.77±8.31 mm,P0.05;54.77±5.84 mm VS.59.87±7.57 mm,P0.05),Cys C较治疗前显著降低(1.00±0.33 mg/LVS.1.27±0.52 mg/L,P0.05),Scr较治疗前无显著性差异(82.24±30.38μmol/LVS.91.19±36.81μmol/L,P0.05)。研究组的LVEF较治疗前显著升高(38.70±7.29%VS.33.53±9.12%,P0.05),LVESD、LVEDD均较治疗前显著降低(43.33±9.10 mm VS.49.47±6.84 mm,P0.05;54.53±6.20 mm VS.60.23±8.30 mm,P0.05),Cys C较治疗前显著降低(1.01±0.26 mg/LVS.1.32±0.53 mg/L,P0.05),Scr较治疗前无显著性差异(84.31±32.25μmol/LVS.94.43±38.73μmol/L,P0.05)。比较两组治疗后各项指标均无显著性差异(P0.05)。结论:在CHF的治疗过程中,沙库巴曲缬沙坦与缬沙坦均能改善心功能,且在短时间内具有一定的肾功能保护作用。  相似文献   
842.
Plant vacuolar Na+/H+ antiporters play important roles in cellular ion homeostasis, vacuolar pH regulation and sequestration of Na+ ions into the vacuole. Previous research showed that hydrophilic C-terminal region of Arabidopsis AtNHX1 negatively regulates the Na+/H+ transporting activity. In this study, we truncated the hydrophilic C terminus of a vacuolar Na+/H+ antiporter gene from Salicornia europaea (SeNHX1) to generate its derivative, SeNHX1- ΔC. Expression of SeNHX1 and SeNHX1- ΔC in yeast mutant showed that SeNHX1 significantly improved the tolerance to NaCl; however, the expression of SeNHX1- ΔC enormously decreased the tolerance to NaCl. Overall, these results suggest that the hydrophilic C-terminal region of SeNHX1 is required for Na+/H+ exchanging activity of SeNHX1.  相似文献   
843.
844.
To analyse the molecular mechanisms of phytoplasma pathogenicity, the comprehensive metabolomic changes of mulberry leaf and phloem sap in response to phytoplasma infection were examined using gas chromatography‐mass spectrometry. The metabolic profiles obtained revealed that the metabolite compositions of leaf and phloem sap were different, and phytoplasma infection has a greater impact on the metabolome of phloem sap than of leaf. Phytoplasma infection brought about the content changes in various metabolites, such as carbohydrates, amino acids, organic acids, etc. Meanwhile, the results of biochemical analysis showed that the degradation of starch was repressed, and the starch content was increased in the infected leaves. In addition, we found that phytoplasma infection changed the levels of abscisic acid and cytokinin and break phytohormone balance. Interestingly, our data showed that the contents of H2O2 and superoxide were increased in the infected leaves, but not in the phloem saps. Based on the results, the expression levels of the genes involved in the metabolism of some changed metabolites were examined, and the potential molecular mechanisms of these changes were discussed. It can be concluded that both the leaf and phloem saps have a complicated metabolic response to phytoplasma infection, but their response mechanisms were different.  相似文献   
845.

Background and Aims

The number of nodules formed on a legume root system is under the strict genetic control of the autoregulation of nodulation (AON) pathway. Plant hormones are thought to play a role in AON; however, the involvement of two hormones recently described as having a largely positive role in nodulation, strigolactones and brassinosteroids, has not been examined in the AON process.

Methods

A genetic approach was used to examine if strigolactones or brassinosteroids interact with the AON system in pea (Pisum sativum). Double mutants between shoot-acting (Psclv2, Psnark) and root-acting (Psrdn1) mutants of the AON pathway and strigolactone-deficient (Psccd8) or brassinosteroid-deficient (lk) mutants were generated and assessed for various aspects of nodulation. Strigolactone production by AON mutant roots was also investigated.

Key Results

Supernodulation of the roots was observed in both brassinosteroid- and strigolactone-deficient AON double-mutant plants. This is despite the fact that the shoots of these plants displayed classic strigolactone-deficient (increased shoot branching) or brassinosteroid-deficient (extreme dwarf) phenotypes. No consistent effect of disruption of the AON pathway on strigolactone production was found, but root-acting Psrdn1 mutants did produce significantly more strigolactones.

Conclusions

No evidence was found that strigolactones or brassinosteroids act downstream of the AON genes examined. While in pea the AON mutants are epistatic to brassinosteroid and strigolactone synthesis genes, we argue that these hormones are likely to act independently of the AON system, having a role in the promotion of nodule formation.  相似文献   
846.
WRKY转录因子普遍存在于植物体内,在植物的抗病防御反应中起重要作用。本实验基于漾濞大泡核桃(Juglans sigillata)中编码WRKY转录因子的EST序列设计引物,采用快速扩增cDNA末端技术,克隆得到一个新的脓Ky基因的全长cDNA序列,命名为JsWRKY1(KJ170895)。JsWRKY1的cDNA全长为1012bp,含有564bp的开放阅读框,154bp 5’-非翻译区以及294bp的3'-非翻译区,编码具有187个氨基酸的蛋白质。JsWRKY1编码的氨基酸序列与已知植物WRKY家族成员间的同源性和聚类分析表明JsWRKY1与来源于可可树(Theobroma cacao)和大豆(Glycinemax)中的wRKY相似性较高,属于IIc类wRKY。qRT-PCR分析结果显示,信号分子水杨酸、茉莉酸、H2O2和乙烯处理可以不同程度地诱导漾濞大泡核桃叶片中JsWRKY1的表达。此外,接种胶孢炭疽菌后JsWRKY1的表达量迅速上升,在接种后4h时达到最高水平,之后表达量逐渐下降,暗示JsWRKY1参与漾濞大泡核桃抗胶孢炭疽菌的防卫反应。  相似文献   
847.
采用国际通用的营养价值评价方法 FAO/WHO,对野生蝉花、蝉花液体发酵菌丝体、蝉花固体培养孢梗束和菌质的蛋白质的营养价值进行了全面评价。结果显示,其蛋白质含量分别为19.65%、25.30%、32.90%和16.17%。野生蝉花和蝉花液体发酵菌丝体的第一限制氨基酸是含硫氨基酸(蛋氨酸和半胱氨酸),蝉花孢梗束的第一限制氨基酸是异亮氨酸,蝉花菌质的第一限制氨基酸是赖氨酸。综合评价,蝉花孢梗束蛋白质的营养价值最高,蝉花菌质蛋白质的氨基酸平衡性较好。  相似文献   
848.
测定了野生地木耳(Nostoc commune Vauch.)中次生代谢产物含量,并与4种常见食用菌藻黑木耳(Auricularia auricular-judae)、银耳(Tremella fuciformis)、紫菜(Porphyra)、海带(Laminaria japonica)进行比较分析,总酚、总黄酮和缩合单宁含量测定采用分光光度法,总生物碱含量测定采用高效液相色谱法(HPLC)。结果显示,野生地木耳中总酚含量为24.255 mg/g±1.631 mg/g,总黄酮含量为5.741 mg/g±0.239 mg/g,总生物碱含量为0.768 mg/g±0.073 mg/g,缩合单宁含量为0.069 mg/g±0.009 mg/g。4种食用菌藻中次生代谢产物含量范围为:总酚(5.520~62.326 mg/g)、总黄酮(0.847~7.010 mg/g)、总生物碱(0.408~4.132 mg/g)、缩合单宁(0.063~0.233 mg/g);比较分析结果显示,野生地木耳次生代谢产物中的总酚和总黄酮物质含量较高,且总酚是主要次生代谢产物,缩合单宁与总生物碱含量较低;总酚含量约为黑木耳和银耳的2倍、紫菜的6倍;总黄酮含量约为黑木耳的7倍,银耳的3倍。  相似文献   
849.
水鳖科(Hydrocharitaceae)海菜花(Ottelia acuminata)是中国西南地区特有的水生单子叶植物。基于AFLP技术的磁珠富集快速分离技术(Fast Isolation by AFLP of Sequences Containing Repeats,FIASCO),共筛选出9对多态性引物并对3个居群45个个体进行分析。结果表明:三个居群的等位基因数目为1~3个,观测杂合度从0.000~0.933,期望杂合度从0.000~0.605。这些筛选出的微卫星引物将用于海菜花后续的谱系地理学和生态遗传学研究。  相似文献   
850.
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