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11.
目的:通过油红O及BODIPY染色选取脂肪代谢理想的细胞模型,并运用高内涵仪器检测SIRT1高表达细胞系中脂肪的变化。方法:在L-02、HepG2、Huh7细胞中进行油红O和BODIPY染色,观察在不同油酸浓度下脂滴的生成情况;将构建成功的SIRT1过表达慢病毒载体GV166.SIRT1及空载体病毒GV166.Control感染L.02细胞,qPCR及Western.Blot检测感染细胞中SIRT1的表达水平;高内涵系统检测L-02SIRT1和L-02control细胞系产生的脂滴荧光强度,以确定油酸诱导的最佳浓度及最佳刺激时间。结果:通过油红O及BODIPY染色发现L-02细胞更适宜作为脂肪代谢的细胞模型;成功构建SIRT1过表达慢病毒载体GV166-SIRT1及空载体病毒GV166.Control,qPCR及Western.Blot检测显示转染病毒后SIRT1在细胞中的表达水平明显升高;在油酸刺激浓度0.4mM、诱导时间12h时,L-02SIRT1细胞中脂滴的荧光强度明显较L.02control为低。且这种差异达到最大化。结论:成功建立SIRT1过表达稳定转染细胞系,并证明高表达SIRT1能够抑制脂肪合成。  相似文献   
12.
水稻温敏叶绿素突变体叶片超微结构的研究   总被引:8,自引:0,他引:8  
对温敏转绿型叶绿素突变体1103S和武金4B“斑马叶”性状表达过程中叶绿素含量、叶绿体超微结构的变化进行了比较研究。结果表明,在一定条件下,叶片的失绿、复绿与叶绿素含量的下降、上升变化趋势一致;叶绿体结构在失绿区表现为严重退化,基粒和基粒片层减少,淀粉粒和嗜锇粒增多;复绿后,其叶绿体结构重建和恢复  相似文献   
13.
 利用变异系数和差异显著性检验,对海南坝王岭等五个海南粗榧群体植株及其不同器官的C、H、N、K等15种化学元素分布及变异进行研究。结果表明:1)海南粗榧(Cephalotaxus mannii Hook.f.)中的化学元素含量分布总体呈Ca>K型,但枝、茎、根、种子等不同器官却表现为K>Ca型;2)海南粗榧群体内各化学元素含量的变异系数较大,但群体内和群体间基本无显著差异;3)海南粗榧不同群体同一器官间元素含量相对稳定,变异系数不太大,群体不同器官间则呈现显著甚至极显著的差异,但不同器官的总体平均值却无显著差异。  相似文献   
14.
A single aspect of the toxic impact of a dredged material disposal site located near a mussel-farming zone was followed for eight months. Acetylcholinesterase activity (AChE) of Mytilus edulis was investigated as a biomarker for possible contamination by neurotoxic compounds (carbamates and/or organophosphorous pesticides). Our observations showed that the enzymatic activities (including AChE) of these harbour mussels were decreased in sites directly and indirectly influenced (according to hydrodynamic conditions) by the dumping of dredged sediments, suggesting possible contamination by pesticides. The strong correlations observed between AChE activity and growth parameters (length and weight) seems to show, however, that the enzyme activity is also indirectly controlled through growth restriction, which may imply limitation of the development of the nervous system in juveniles. The concentration of total proteins, as well as the spawning process also seem to disturb the assessment of AChE activity. These field observations clearly indicate that the use of this enzyme activity as a biomarker should proceed with caution. For example, the seasonal variability of such activity should be taken into account in a biomonitoring programme.  相似文献   
15.
目的:建立桂皮醛亚微乳注射剂中桂皮醛含量的测定方法。方法:采用高效液相色谱法,按照固定相为色谱柱Diamonsil C18柱(250 mm×4.6 mm,5μm);流动相为乙腈:0.5%冰乙酸水溶液(60:40),检测波长为288 nm,流速为1.0 m L·min~(-1),柱温为25℃,进样量为10μL的进样条件,测定桂皮醛亚微乳注射剂中桂皮醛的含量。结果:桂皮醛在5~100μg·mL~(-1)浓度范围内呈良好的线性关系,标准曲线方程为Y=1703 X-1996(r~2=0.999,n=6)。在低、中、高三个浓度下,一天内连续3次和连续3天测定样品,测定的RSD值均小于2.0%,精密度良好。加速试验中,在温度30℃,相对湿度60%的条件下放置6个月,样品测定结果与0天相比无变化。本实验中3批桂皮醛亚微乳注射剂中桂皮醛含量的均值为19.89μg·mL~(-1),平均回收率为100.98%,RSD为1.45%。结论:本方法操作简便、快速准确,稳定性高,系统重现性良好可有效控制桂皮醛亚微乳注射剂中有效成分含量。  相似文献   
16.
The Creative Commons (CC) licenses are a suite of copyright-based licenses defining terms for the distribution and re-use of creative works. CC provides licenses for different use cases and includes open content licenses such as the Attribution license (CC BY, used by many Open Access scientific publishers) and the Attribution Share Alike license (CC BY-SA, used by Wikipedia, for example). However, the license suite also contains non-free and non-open licenses like those containing a "non-commercial" (NC) condition. Although many people identify "non-commercial" with "non-profit", detailed analysis reveals that significant differences exist and that the license may impose some unexpected re-use limitations on works thus licensed. After providing background information on the concepts of Creative Commons licenses in general, this contribution focuses on the NC condition, its advantages, disadvantages and appropriate scope. Specifically, it contributes material towards a risk analysis for potential re-users of NC-licensed works.  相似文献   
17.
Irradiated carrageenan (IC) could elicit plant growth promoting activities in plants. The effect of foliar spray of five concentrations of IC (20, 40, 60, 80 and 100 mg L−1) was studied on Mentha arvensis L. in terms of plant growth, physiological attributes, herbage yield and the content and yield of essential oil and its components. Un-irradiated carrageenan and deionized water had no effect on the attributes studied. GPC study revealed formation of low molecular weight fractions in irradiated samples containing less than 20,000 molecular weight oligomers which are responsible for plant growth promotion in this study. 80 mg L−1 of IC was the most effective concentration which resulted in the highest values of growth attributes, herbage yield and the content and yield of essential oil and menthol content of the oil. It also improved the leaf-nutrient contents, photosynthetic rate and other physiological parameters. 100 mg L−1 of IC did not further improve the attributes studied, but it was always better than the control.  相似文献   
18.
Oncogenic mutant Ras is frequently expressed in human cancers, but no anti-Ras drugs have been developed. Since membrane association is essential for Ras biological activity, we developed a high content assay for inhibitors of Ras plasma membrane localization. We discovered that staurosporine and analogs potently inhibit Ras plasma membrane binding by blocking endosomal recycling of phosphatidylserine, resulting in redistribution of phosphatidylserine from plasma membrane to endomembrane. Staurosporines are more active against K-Ras than H-Ras. K-Ras is displaced to endosomes and undergoes proteasomal-independent degradation, whereas H-Ras redistributes to the Golgi and is not degraded. K-Ras nanoclustering on the plasma membrane is also inhibited. Ras mislocalization does not correlate with protein kinase C inhibition or induction of apoptosis. Staurosporines selectively abrogate K-Ras signaling and proliferation of K-Ras-transformed cells. These results identify staurosporines as novel inhibitors of phosphatidylserine trafficking, yield new insights into the role of phosphatidylserine and electrostatics in Ras plasma membrane targeting, and validate a new target for anti-Ras therapeutics.  相似文献   
19.
AAS法测定陕产不同生长期女贞子中铁含量   总被引:1,自引:0,他引:1  
目的:对陕西境内不同产地、不同生长期女贞子中Fe含量进行分析测定.方法:采收陕西境内关中3市(渭南、西安、宝鸡)与陕南2市(安康、汉中)10月产女贞子;并采收西安8、9、10、11和12月产女贞子,去杂质阴干,室温密闭贮藏.样品湿法消解以后,采用火焰原子吸收光谱法检测其中的Fe含量,考察了干扰情况、方法的准确度和精密度.结果:本方法的检出限均小于0.3μg·mL-1,RSD≤2.46%,加样回收率在97.6~103.8%范围内.实际检测结果显示女贞子中铁含量较为丰富.结论:女贞子在不同产地、不同生长期铁含量不同,故在实际应用时应根据实际药用需要适时采集.  相似文献   
20.
 本文报道了内蒙古沙地草场不同植物根系的化学元素含量特征。结果表明:51种植物根系的N、P、K、Si、Na、Fe和灰分的平均含量分别为1.08%、0.104%、0.686%、0.811%、0.049%、0.030%和6.416%。其中相同植物根系的N、P、K、Na和灰分的含量低于其地上部分的平均含量,而Si和Fe相反,根系的平均含量高于其地上部分。  相似文献   
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