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401.
Organic compounds containing phenanthroimidazole, and its optical, thermal, chemical, and high fluorescence, have drawn the interest of numerous researchers. Phenanthroimidazole derivatives are appealing for various applications due to these characteristics. This research provides a summary of the general information contained in studies on the synthesis, characterization, photophysical characteristics, and possible applications of phenanthroimidazole derivative compounds. The focus of this study revolves around the topic of utilization in technological fields such as sensors, solar cells, optical brighteners, and organic light-emitting diodes, and covers significant studies on mentioned topics. We anticipate that this study will provide an outline for researchers aiming to further examine fluorescent organic compounds for technological innovations. Furthermore, we anticipate that this research will be crucial in developing long-term high-organic compounds for optoelectronic devices. 相似文献
402.
Assoc. Prof. Gülnur Ekşi Bona Prof. Dr. Gülşen Akalın Çiftçi Prof. Dr. Betül Demirci Prof. Dr. Nur Münevver Pınar Assist. Prof. Aydan Acar Şahin Assoc. Prof. Mine Koçyiğit Assoc. Prof. Mehmet Bona Prof. Dr. Ayşe Mine Gençler Özkan 《化学与生物多样性》2023,20(5):e202201194
Garlic and onions are used as food and for medicinal purposes worldwide. Allium L. species are rich in bioactive organosulphur compounds that exhibit many biological activities like anticancer, antimicrobial, antihypertensive, antidiabetic activities. In this study, macro- and micromorphological characteristics of four Allium taxa were examined and the results suggested that A. callimischon subsp. haemostictum was the outgroup to sect. Cupanioscordum. Also, for the genus Allium, which is a taxonomically difficult genus, the hypothesis that chemical content and bioactivity can also be used taxonomically in addition to micro and macromorphological characters has been questioned. The bulb extract was analyzed to determine their volatile compositions and anticancer activities against human breast cancer, human cervical cancer, and rat glioma cells for the first time in the literature. To detect the volatiles, the Head Space-Solid Phase Micro Extraction method was used followed by Gas Chromatography-Mass Spectrometry. The main compounds were found as dimethyl disulfide that (36.9 %, 63.8 %, 81.9 %, 12.2 %) and methyl (methylthio)-methyl disulfide (10.8 %, 6.9 %, 14.9 %, 60.0 %) for A. peroninianum, A. hirtovaginatum and A. callidyction, respectively. Additionally, methyl-trans-propenyl disulfide is detected for A. peroniniaum (36 %). As a result, all extracts have shown significant efficacy against MCF-7 cells depending on applied concentrations. The treatment of MCF-7 cells for 24 h with 10, 50, 200, or 400 μg/mL ethanolic bulb extract of four Allium species resulted in DNA synthesis inhibition. Survival rates for A. peroninianum was 51.3 %, 49.7 %, 42.2 %, 42.0 %, for A. callimischon subsp. haemostictum 62.5 %, 63.0 %, 23.2 %, 22 %, for A. hirtovaginatum 52.9 %, 42.2 %, 42.4 %, 39.9 %, for A. callidyction 51.8 %, 43.2 %, 39.1 %, 31.3 %, for cisplatin 59.6 %, 59.9 %, 50,9 %, 48.2 %, respectively. Moreover, taxonomic evaluation according to biochemical compounds and bioactivities is almost in agreement with that made according to micro and macromorphological characters. 相似文献
403.
Serap Cilaker Micili Asli Goker Oya Sayin Pinar Akokay Bekir Uğur Ergur 《Journal of molecular histology》2013,44(3):339-345
Aim of this study was to investigate the effects of lipoic acid on uterine wound healing by immunohistochemical and biochemical assay in a rat uterine horn model with full thickness injury. Thirty-two female Wistar albino rats were randomised into five groups: Control group, with no intervention; uterine scar group 15days (US15d), uterine scar group 15 days + alpha lipoic acid (ALA) (US15d + ALA), uterine scar group 30 days (US30d) and uterine scar group 30 days + ALA (US30 days + ALA). After uterine incision 100 mg/kg of ALA was administered by oral gavage for either 15 or 30 days. Vascular endothelial growth factor (VEGF) and alpha smooth muscle actin (α-SMA) distribution were evaluated by immunohistochemical methods in tissue and ELISA methods in tissue homogenate. The percentage of α-SMA positive area in US15d + ALA and US30d + ALA groups was significantly higher than US15 and US30d groups. The percentage of VEGF positive area in US15d + ALA group was significantly higher than US15d group and US30d + ALA group was significantly higher than US30d group. Biochemically, α-SMA was significantly higher in the US15d + ALA group when compared to US15d group and higher in US30d + ALA group when compared to US30d group. VEGF was significantly higher in US15d + ALA and US30d + ALA groups when compared to US15 and US30d groups. In conclusion, ALA was found to be effective in enhancing wound healing in uterine full thickness injury. 相似文献
404.
Xylanases are the main biocatalysts used for the reduction of the xylan backbone from hemicellulose, randomly splitting off β-1,4-glycosidic linkages between xylopyranosyl residues. Xylanase market has been annually estimated at 500 million US Dollars and they are potentially used in broad industrial process ranges such as paper pulp biobleaching, xylo-oligosaccharide production, and biofuel manufacture from lignocellulose. The highly stable xylanases are preferred in the downstream procedure of industrial processes because they can tolerate severe conditions. Almost all native xylanases can not endure adverse conditions thus they are industrially not proper to be utilized. Protein engineering is a powerful technology for developing xylanases, which can effectively work in adverse conditions and can meet requirements for industrial processes. This study considered state-of-the-art strategies of protein engineering for creating the xylanase gene diversity, high-throughput screening systems toward upgraded traits of the xylanases, and the prediction and comprehensive analysis of the target mutations in xylanases by in silico methods. Also, key molecular factors have been elucidated for industrial characteristics (alkaliphilic enhancement, thermal stability, and catalytic performance) of GH11 family xylanases. The present review explores industrial characteristics improved by directed evolution, rational design, and semi-rational design as protein engineering approaches for pulp bleaching process, xylooligosaccharides production, and biorefinery & bioenergy production. 相似文献
405.
Ceren Keçeciler-Emir Yeliz Başaran-Elalmiş Yeşim Müge Şahin Erdi Buluş Sevil Yücel 《Biopolymers》2023,114(10):e23562
Polymeric barrier membranes are used in periodontal applications to prevent fibroblastic cell migration into the cavities of bone tissue and to properly guide the proliferation of tissues. In this study, the fabrication, characterization, bioactivity, and in vitro biological properties of polyvinyl alcohol-based nanofibrous membranes containing nano-sized 45S5 bioactive glass (BG) loaded with chlorhexidine (CH) gluconate with biocompatible, bioactive, and antibacterial properties for using as dental barrier membranes were investigated. Nanofibrous membranes with an average fiber diameter, pore size, and porosity of 210 nm, 24.73 μm, and 12.42%, respectively, were loaded with 1% and 2% CH, and the release profile was investigated. The presence of BG in the membranes promoted fibroblastic proliferation and the presence of CH provided antibacterial properties. Nanofibrous membranes exhibit a high ability to restrict bacterial growth while fulfilling the necessary conditions for use as a dental barrier thanks to their low swelling rates, significant surface bioactivities, and appropriate degradation levels. 相似文献
406.
Gonul ŞimŞek Gulnur Andican Yunus Karako© Gunner Yiğit Husrev Hatemi Gulden Candan 《Biological trace element research》1997,60(3):205-213
In this study, experimental hypothyroidism was established and used to investigate possible alterations in the calcium, magnesium,
and zinc homeostasis by assessing their concentration in plasma and erythrocytes. Hypothyroidism was induced by administration
of methimazole an iodine blocker at a dose of 75 mg/100 g food for 3 wk.
In the methimazole-induced hypothyroid state, the experimental animals showed a significant decrease in plasma zinc concentration,
whereas a significant increase in plasma magnesium concentration occurred. No change was observed in plasma calcium concentration.
The erythrocyte zinc and calcium concentrations were found to be increased, whereas magnesium concentration decreased. Erythrocyte
magnesium concentration showed a significant positive correlation with T4 values.
The study provides evidence for marked alterations in homeostatis of zinc, magnesium, and calcium. 相似文献
407.
408.
Nevra Öztürk Raziye Hilal Şenay Nesibe Avcıbaşı Sinan Akgöl Adil Denizli 《Process Biochemistry》2012,47(5):816-821
Novel hydrophobic nanospheres with an average size of 200 nm utilizing N,N′-bis-(3-(4-morpholino)-propyl)-3,4,9,10-perylenetetracarboxylic acid dimide (MPPDI) as a monomer were prepared by surfactant free emulsion polymerization of 2-hydroxyethyl methacrylate (HEMA) and MPPDI conducted in an aqueous dispersion medium. The nanospheres were used for the adsorption of lysozyme. The system parameters, such as effect of the adsorption conditions (i.e. enzyme concentration, medium pH, and temperature) and the reusability of the support were studied. Specific surface area of the nonporous nanospheres was found 664 m2/g. Poly(HEMA–MPPDI) nanospheres were characterized by Fourier transform infrared spectroscopy (FT-IR), elemental analysis and scanning electron microscopy (SEM). Then, poly(HEMA–MPPDI) nanospheres were used in the adsorption of lysozyme in batch system. Using an optimized adsorption protocol, 400 mg lysozyme/g nanosphere loading capacity was obtained. The adsorption phenomena appeared to follow a typical Langmuir isotherm. Lysozyme could be repeatedly adsorbed and desorbed with poly(HEMA–MPPDI) nanospheres without noticeable loss in the adsorption capacity. 相似文献
409.
Mustafa Calapoğlu Orhan Değer Fulya Balaban Nilufer Şahin Calapoğlu Yılmaz Bülbül Keith Burling 《Biochemical genetics》2009,47(1-2):33-41
Deficiency of alpha-1-antitrypsin (α1-AT, a major protease inhibitor controlling tissue degradation) is a genetic disorder transmitted in a codominant autosomal form. It has more than 100 genetically determined variants. This study attempted to determine the degree of association between serum α1-AT levels and phenotypes and to provide a strategy for reliable laboratory evaluation of deficiencies. The study group consisted of a 38-year-old male proband with clinical features of emphysema, his first-degree relatives, and healthy controls. Family history revealed a four-generation pedigree. Genomic DNA was isolated from peripheral blood leukocytes. Alpha-1-AT levels were determined from human serum by immunonephelometry. Phenotypes were determined by isoelectric focusing of blood samples. DNA sequences of coding exons were analyzed by the amplification DNA technique and direct sequencing. Inheritance and plasma levels of the ZZ, MM, M3S, and MZ phenotypes were confirmed by the family study. In the family members with deficiencies, plasma concentrations were 22.55% ± 5.15 (ZZ), 84.18% ± 5.18 (M3S), and 61.06% ± 7.15 (MZ) of the normal MM level. We found a close association between α1-AT level and genotype. A combination of genotyping, quantification, and phenotyping is the optimal strategy for the laboratory evaluation of α1-AT deficiency. 相似文献
410.