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131.
细胞色素c在线粒体中的抗氧化功能   总被引:3,自引:0,他引:3       下载免费PDF全文
实验论证了细胞色素c在线粒体中具有很强的抗氧化能力,氧化态细胞色素c能清除O2-.,还原态细胞色素c能清除H2O2。  相似文献   
132.
目的:观察逍遥散治疗慢性乙型病毒性肝炎的临床疗效。方法:100例慢性乙型病毒性肝炎患者随机分为两组,观察组50例在对照组基础上口服逍遥散,150ml/次,3次/d;对照组50例口服恩替卡韦分散片,0.5mg/次,1次/d。两组患者均治疗3个疗程共12周,观察两组患者治疗前后的临床症状、体征、HBV-DNA、肝功能的变化程度。结果:观察组患者临床疗效总有效率显著高于对照组(98%vs 84%),两组间比较差异有显著性意义(P0.05)。结论:加服逍遥散治疗慢性乙型病毒性肝炎有较好的疗效,值得临床进一步研究应用。  相似文献   
133.
在数字通信中,接收信号通常会受到码间干扰的影响,尤其是在多径衰弱无线信道环境中,这种现象更为严重。采用盲均衡技术可以消除码间干扰。针对基于常数模算法的判决反馈盲均衡收敛速度慢,稳态误差大的缺点,提出了一种新的多模判决反馈盲均衡算法。算法用信号的独立模值取代常数模算法的模值,加快了收敛速度减小了稳态误差。通过计算法仿真对两种算法进行比较,仿真结果证明了新算法的有效性。  相似文献   
134.
Die durch das UG 2002 mit größerer Autonomie ausgestatteten Universitäten nützen diese auch zur Kooperation bei der Einrichtung von interuniversitären Studien. Die rechtlichen Rahmenbedingungen für diese sind jedoch nur rudimentär. Es ist nicht möglich, gemeinsame Organe (Curriculakommissionen, monokratische Organe) für derartige Studien einzurichten. Möglich ist nur, ein Organ zu schaffen, das durch Personalunionen für beide Universitäten entscheidet. Bei der Durchführung der Studien kommt den Studierenden ein Wahlrecht hinsichtlich der Universität der Zulassung zu. Bei prüfungsrelevanten Fragestellungen richtet sich die Zuständigkeitsverteilung zwischen den Universitäten nach dem Curriculum und den dort vorgesehenen Prüfungen. Dies führt dazu, dass zB Studierende in einem interuniversitären Studium je nach Prüfungsuniversität eine unterschiedliche Anzahl von Prüfungsantritten haben können.  相似文献   
135.
Gestational diabetes mellitus(GDM) is characterized by glycemia and insulin disorders.Bile acids(BAs) have emerged as vital signaling molecules in glucose metabolic regulation.BA change in GDM is still unclear,which exerts great significance to illustrate the change of BAs in GDM.GDM patients and normal pregnant women were enrolled during the oral glucose tolerance test(OGTT) screening period.Fasting serums were sampled for the measurement of BAs.BA metabolism profiles were analyzed in both pregnant women with GDM and those with normal glucose tolerance(NGT).Delivery characteristics,delivery gestational age,and infant birthweight were extracted from medical records.GDM patients presented distinctive features compared with NGT patients,including higher body mass index(BMI),elevated serum glucose concentration,raised insulin(both fasting and OGTT),and increased hemoglobin A1 c(HbA1c) levels.Higher homeostasis model assessment of insulin resistance(HOMA-IR) and decreased β-cell compensation(i.e.,oral disposition index(DIo)) were also prevalent in this group.Total BAs(TBAs) remained stable,but glycodeoxycholic acid(GDCA) and taurodeoxycholic acid(TDCA) levels declined significantly in GDM.GDCA was inversely correlated with HOMA-IR and positively correlated with DIo.No obvious differences in clinical outcome between the GDM and NGT groups were observed.However,GDM patients with high HOMA-IR and low DIo tended to have a higher cesarean delivery rate and younger delivery gestational age.In conclusion,GDCA provides a valuable biomarker to evaluate HOMA-IR and DIo, and decreased GDCA levels predict poorer clinical outcomes for GDM.  相似文献   
136.
The need to preserve cultural heritage on paper requires the setting up of methods and treatments that can be applied to original documents. The cellulose main degradation processes are hydrolysis and oxidation. Only the first one has been widely investigated. The Istituto Centrale per la Patologia del Libro (ICPL) focused its attention on oxidation phenomena and studied a particular class of reducing agents, namely the borane-amine complexes. During the investigation it was found that the borane tert-butylamine complex, besides being the most promising reducing agent, was also able to react with carboxylic functions. In the present study 1H and 13C NMR, Pulsed field gradient NMR spectroscopy as well as Raman spectroscopy were used as analytical tools to disclose the mechanism of the interaction between the borane tert-butylamine complex and the carboxylic functions. Given the complexity of the paper/environment interactions and the subsequent degradation phenomena, we worked on simplified models based on small carbohydrate molecules in order to reproduce the behavior of degraded paper after reductive restoration. Modified D-glucose and D-cellobiose were used in this first step in order to set up the analytical methods before approaching more complex systems such as microcrystalline cellulose and paper. Our results give the experimental evidence that borane tert-butylamine complex is also able to neutralize acidic functions. This finding has important perspectives in paper restoration.  相似文献   
137.
通过分子动力学模拟,研究细胞色素c在氧化石墨烯表面的吸附行为.结果表明,细胞色素c和氧化石墨烯之间有较强的结合趋势.均方根涨落及回转半径分析表明,部分体系的吸附构象与原始构象比较接近,但P3系统有着较大的偏离.这些结果表明,在某些构象中,氧化石墨烯可能将细胞色素c结构破坏.  相似文献   
138.
In the creation myth of the Crusades, Pope Urban II (r. 1088–1099) is the founding father and 1095 is the critical year. During the twentieth century, French, Spanish, and English scholars challenged this myth; yet this myth remains as durable as ever. Because the origins of the crusading enterprise came to be associated with the so-called First Crusade (1095–1102), scholars have created a vision of crusading at odds with Pope Urban's vision, which views the “First” Crusade as the third part of a triptych: first, the Norman conquest of Sicily (1060–1091); then, the Castilian and Catalan advances in Iberia; and finally the 1095 Eastern Crusade. Today, the study of the Crusades is hampered by a failure to concentrate on the direct evidence and to take into account what contemporaries understood by crusading. To get a sense of what contemporaries understood by crusading, this paper examines the Norman Crusade in Sicily, drawing upon both Christian and Islamic sources.  相似文献   
139.
140.
细胞色素c吸附在氧化石墨烯表面后会发生电子转移反应,计算二者之间的电子转移耦合矩阵元对研究二者的相互作用有重要意义。通过路径通道分析方法对8个细胞色素c-氧化石墨烯体系的电子转移耦合矩阵元的计算结果表明,P8体系的电子转移耦合矩阵元最大,细胞色素c与氧化石墨烯之间的电子相互作用最强。  相似文献   
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