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121.
Zeyad I. Alehaideb Anuradha Venkatraman Mahadev Kokane Syed Ali Mohamed Saranya Rameshbabu Rasha S. Suliman Sahar S. Alghamdi Hamad Al-Eidi Bandar Alghanem Maha-Hamadien Abdulla Sabine Matou-Nasri 《Molecules (Basel, Switzerland)》2022,27(3)
Liver cancer is a leading cause of cancer death globally. Marine mollusc-derived drugs have gained attention as potential natural-based anti-cancer agents to overcome the side effects caused by conventional chemotherapeutic drugs during cancer therapy. Using liquid chromatography-mass spectrometry, the main biomolecules in the purple ink secretion released by the sea hare, named Bursatella leachii (B. leachii), were identified as hectochlorin, malyngamide X, malyngolide S, bursatellin and lyngbyatoxin A. The cytotoxic effects of B. leachii ink concentrate against human hepatocarcinoma (HepG2) cells were determined to be dose- and time-dependent, and further exploration of the underlying mechanisms causing the programmed cell death (apoptosis) were performed. The expression of cleaved-caspase-8 and cleaved-caspase-3, key cysteine-aspartic proteases involved in the initiation and completion of the apoptosis process, appeared after HepG2 cell exposure to the B. leachii ink concentrate. The gene expression levels of pro-apoptotic BAX, TP53 and Cyclin D1 were increased after treatment with the B. leachii ink concentrate. Applying in silico approaches, the high scores predicted that bioactivities for the five compounds were protease and kinase inhibitors. The ADME and cytochrome profiles for the compounds were also predicted. Altogether, the B. leachii ink concentrate has high pro-apoptotic potentials, suggesting it as a promising safe natural product-based drug for the treatment of liver cancer. 相似文献
122.
本文研究了二十种2-甲基-3-二苯基甲醇衍生物衍生物作为PD-L1抑制剂的定量结构活性关系. 用密度泛函理论在B3LPY/6-31+G(d,p)水平对它们的结构和性质进行计算,求得最高占有轨道能级EHOMO、最低空轨道能级ELUMO、总能量ET、 偶极矩DM、绝对硬度?、绝对电负性χ、软度S、电负性ω和能隙ΔE等性质. 用主成分分析(PCA)、多元线性回归(MLR)和多元非线性回归(MNLR)建立它们的定量结构活性关系(QSAR). 基于统计分析构建定量模型并预测化合物的性质. MLR和MNLR统计结果的相关系数R2分别为0.661和0.758. 用留一法交叉检验(LOO-CV),r2m检验和“Golbraikh&Tropsha”标准分析用于检验MLR和MNLR模型的稳健性. 结果表明两种模型均具有统计显著性和稳健性,两种模型均能预测其生物活性,可用于PD-L1免疫检查点抑制剂生物活性的预估. 相似文献
123.
Halla Mohamed Ragab Nabila Abd El Maksoud Mona A. Amin Mohab H. Halim Nour A. Abdulla Abdelkarim Kamel Shorouk M. Moussa 《Applied biochemistry and biotechnology》2018,184(2):484-499
Fatty acid desaturases (FADs) catalyze the introduction of a double bond into acyl chains. Two FAD groups have been identified in plants: acyl-acyl carrier proteins (ACPs) and acyl-lipid or membrane-bound FAD. The former catalyze the conversion of 18:0 to 18:1 and to date have only been identified in plants. The latter are found in eukaryotes and bacteria and are responsible for multiple desaturations. In this study, we identified 82 desaturase gene and protein sequences from 10 grass species deposited in GenBank that were analyzed using bioinformatic approaches. Subcellular localization predictions of desaturase family revealed their localization in plasma membranes, chloroplasts, endoplasmic reticula, and mitochondria. The in silico mapping showed multiple chromosomal locations in most species. Furthermore, the presence of the characteristic histidine domains, the predicted motifs, and the finding of transmembrane regions strongly support the protein functionality. The identification of putative regulatory sites in the promotor and the expression profiles revealed the wide range of pathways in which fatty acid desaturases are involved. This study is an updated survey on desaturases of grasses that provides a comprehensive insight into diversity and evolution. This characterization is a necessary first step before considering these genes as candidates for new biotechnological approaches. 相似文献
124.
Belal H M Hussein Mostafa A Gouda Omer Sakin Abdulla Faluji Mohamed Gomaa Hassan A Azab Walid Fathalla Sherin Arabi Sawsan Mosa 《光谱学与光谱分析》2018,38(11):3611-3621
A new europium (Ⅲ) complex containing (4-Methyl-2-oxo-2H-chromen-7-yloxy)-acetic acid moiety (CMMC) was synthesized, characterized, and confirmed as antitumor agent and fluorescent probe. The spectroscopic measurements of Eu(Ⅲ) in the presence of CMMC were obtained in different solvents. The results show that the strongest Eu(Ⅲ) emission bands were monitored in iso-propyl alcohol while the weakest Eu(Ⅲ) emission band was observed in acetonitrile. The interaction of Eu(Ⅲ)-(CMMC)2 complex with DNA was monitored using absorption and emission techniques. From fluorescence titration measurements, the binding constants of DNA with Eu(Ⅲ)-(CMMC)2 complex were found to be 1.04×105 L·mol-1 in Tris-HCl and 1.17×107 L·mol-1 in DMSO-Tris-HCl buffer (9∶1 V/V). Hypochromism was observed from the absorption titration experiment which indicates the intercalation of Eu(Ⅲ)-complex between the base pair of DNA. This result further confirmed by fluorescent Ethidium bromide displacement assay. The fluorescence calibration curve was used for the determination of DNA with LOD of 1.2 ng in DMSO-Tris-HCl buffer (9∶1 V/V) and 5 ng in Tris-HCl buffer. The preliminary antitumor investigation shows promising cytotoxicity against MDA-MB-231, MCF-7 (mammary cancer), and PC-3 (prostate carcinoma) cell lines with IC50 values of 40.63, 25.42 and 30.25 μmol·L-1, respectively. 相似文献
125.
The European Physical Journal C - 相似文献
126.
Design,Docking, and Synthesis of Some New Pyrazoline and Pyranopyrazole Derivatives as Anti‐inflammatory Agents
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Magda M. F. Ismail Nagy M. Khalifa Hoda H. Fahmy Eman S. Nossier Mohamed M. Abdulla 《Journal of heterocyclic chemistry》2014,51(2):450-458
Design and synthesis of some novel pyrazoline and pyranopyrazole derivatives as potential anti‐inflammatory agents are described. Most of the compounds were tested for their anti‐inflammatory (in vitro and in vivo) and ulcerogenic activities. In all tested compounds, it was found that pyrazolines, 2a , and pyrazolopyrano[2,3‐d]pyrimidine 9 are the potent anti‐inflammatory and selective cyclooxygenase‐2 (COX‐2) inhibitor. All compounds are mainly in the safe level. Docking study of 2a and 9 revealed higher affinity for binding with the active site of COX‐2 enzyme like SC‐558, a selective COX‐2 inhibitor. 相似文献
127.
Mohd F. Ain Seyi S. Olokede Yazeed M. Qasaymeh Arjuna Marzuki Julie J. Mohammed Srimala Sreekantan Sabar D. Hutagalung Zainal A. Ahmad Mohd Z. Abdulla 《AEUE-International Journal of Electronics and Communications》2013,67(7):557-563
In this paper, a novel quasi-lumped element resonator antenna is presented. The proposed antenna consists of the interdigital capacitor in parallel with a straight line inductor and is fabricated on Duroid RC4003C circuit board. The entire arrangement was fed by a coaxial feed at a frequency of 5.8 GHz. The size, bandwidth and radiation patterns were studied. The proposed antenna exhibits better impedance bandwidth and significant size reduction in comparison with similar results obtained from the conventional microstrip patch antenna with similar feeding technique and resonant frequency. The size of the proposed antenna structure is 5.8 × 5.6 mm2 and experimental results are shown to be in good agreement with the design simulation. 相似文献
128.
Xiangyin Zeng Jiangqi He Mingchang Wang Abdulla M. 《Microwave and Wireless Components Letters, IEEE》2007,17(11):781-783
Time domain reflectometry has been widely used to characterize high speed interconnects. The equivalent lumped LC model is then developed based on the measured impedance profile (Z-profile). However, for discrete L or C, mounted in the middle of transmission line interconnects, the current formula based on Z-profile cannot provide correct results. In this letter, a new closed-form formula based on the Z-profile is derived to determine the lumped L or C with the rise time of the incident step taken into account, which is easy to integrate into any EDA tools. 相似文献
129.
Taha M. A. Eldebss Xue-Jing Yi Ahmad M. Farag Ahmad A. Khedr Mohamed M. Abdulla Yahia N. Mabkhot 《Journal of the Iranian Chemical Society》2018,15(8):1785-1800
A series of new substituted pyrazoles embedded with a variety of function groups has been synthesized from 4-[4-(1,2-dihydro-2,3-dimethyl-1-phenyl-5-oxo-3H-pyrazol-4-yl)]-2-cyano-4-oxo-butanenitrile (4). The synthesized compounds were fully characterized and their structures were elucidated based on elemental analysis, spectral data, and alternative synthetic pathways, whenever possible. The pharmacological activities of these new compounds as inhibitors for of type A and type B monoamine oxidase (MAO) enzymes have been investigated and compared to the most common inhibitors of MAO enzymes used to treat depression and anxiety such as deprenyl (selegiline), moclobemide, and clorgyline drugs. The most potent of the synthesized compounds was 4, 11, and 53 which showed higher inhibition activity toward type A MAO enzyme and even exceeded that of deprenyl, moclobemide, and clorgyline drugs. 相似文献
130.
The kinetics and mechanism of the oxidation of [CrIII(DPA)(IDA)(H2O)]? (DPA = dipicolinate and IDA = iminodiacetate) by periodate in the presence of Mn(II) as a catalyst have been investigated. The rate of the reaction increases with increasing pH, due to the deprotonation equilibria of the complex. Addition of Mn(II) in the concentration range of (2.5–10) × 10?6 mol dm?3 enhanced the reaction rate; the reaction is first order with respect to both [IO4 ?] and the Cr complex, and obeys the following rate law: \( {\text{Rate}} = [ {\text{Cr}}^{\text{III}} ({\text{DPA}})({\text{IDA}})({\text{H}}_{2} {\text{O}})^{ - } ][{\text{Mn}}^{\text{III}} ]\{ (k_{7} + K_{1} k_{8} /[{\text{H}}^{ + } ]) + [{\text{I}}^{\text{VII}} ]((k_{9} k_{11} /k_{ - 9} + k_{11} ) + (K_{1} k_{10} k_{12} )/(k_{ - 10} + k_{12} )[{\text{H}}^{ + } ])\} . \) Catalysis by Mn(II) is believed to be due to initial oxidation of Mn(II) to Mn(III), which acts as the oxidizing agent. It is proposed that electron transfer proceeds through an inner-sphere mechanism via coordination of IO4 ? to Cr(III). Thermodynamic activation parameters were calculated using the transition state theory equation. 相似文献