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51.
Ni Made Dwi Mara Widyani Nayaka Maria Malida Vernandes Sasadara Dwi Arymbhi Sanjaya Putu Era Sandhi Kusuma Yuda Ni Luh Kade Arman Anita Dewi Erna Cahyaningsih Rika Hartati 《Molecules (Basel, Switzerland)》2021,26(8)
Piper betle (L) is a popular medicinal plant in Asia. Plant leaves have been used as a traditional medicine to treat various health conditions. It is highly abundant and inexpensive, therefore promoting further research and industrialization development, including in the food and pharmaceutical industries. Articles published from 2010 to 2020 were reviewed in detail to show recent updates on the antibacterial and antifungal properties of betel leaves. This current review showed that betel leaves extract, essential oil, preparations, and isolates could inhibit microbial growth and kill various Gram-negative and Gram-positive bacteria as well as fungal species, including those that are multidrug-resistant and cause serious infectious diseases. P. betle leaves displayed high efficiency on Gram-negative bacteria such as Escherichia coli and Pseudomonas aeruginosa, Gram-positive bacteria such as Staphylococcus aureus, and Candida albicans. The ratio of MBC/MIC indicated bactericidal and bacteriostatic effects of P. betle leaves, while MFC/MIC values showed fungicidal and fungistatic effects. This review also provides a list of phytochemical compounds in betel leaves extracts and essential oils, safety profiles, and value-added products of betel leaves. Some studies also showed that the combination of betel leaves extract and essential oil with antibiotics (streptomycin, chloramphenicol and gentamicin) could provide potentiating antibacterial properties. Moreover, this review delivers a scientific resume for researchers in respected areas and manufacturers who want to develop betel leaves-based products. 相似文献
52.
Dr. Alif Sussardi Dr. Ross J. Marshall Prof. Stephen A. Moggach Prof. Anita C. Jones Prof. Ross S. Forgan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(60):14871-14875
Photophysical studies of chromophoric linkers in metal–organic frameworks (MOFs) are undertaken commonly in the context of sensing applications, in search of readily observable changes of optical properties in response to external stimuli. The advantages of the MOF construct as a platform for investigating fundamental photophysical behaviour have been somewhat overlooked. The linker framework offers a unique environment in which the chromophore is geometrically constrained and its structure can be determined crystallographically, but it exists in spatial isolation, unperturbed by inter-chromophore interactions. Furthermore, high-pressure studies enable the photophysical consequences of controlled, incremental changes in local environment or conformation to be observed and correlated with structural data. This approach is demonstrated in the present study of the trans-azobenzene chromophore, constrained in the form of the 4,4’-azobenzenedicarboxylate (abdc) linker, in a UiO topology framework. Previously unobserved effects of pressure-induced solvation and conformational distortion on the lowest energy, nπ* transition are reported, and interpreted the light of crystallographic data. It was found that trans-azobenzene remains non-fluorescent (with a quantum yield less than 10−4) despite the prevention of trans-cis isomerization by the constraining MOF structure. We propose that efficient non-radiative decay is mediated by the local, pedal-like twisting of the azo group that is evident as dynamic disorder in the crystal structure. 相似文献
53.
54.
Weixun Wang Bernard K. Choi Wenyu Li Zhege Lao Anita Y. H. Lee Sandra C. Souza Nathan A. Yates Timothy Kowalski Alessandro Pocai Lucinda H. Cohen 《Journal of the American Society for Mass Spectrometry》2014,25(4):614-625
Stromal cell-derived factor 1α (SDF-1α) or CXCL12 is a small pro-inflammatory chemoattractant cytokine and a substrate of dipeptidyl peptidase IV (DPP-IV). Proteolytic cleavage by DPP-IV inactivates SDF-1α and attenuates its interaction with CXCR4, its cell surface receptor. To enable investigation of suppression of such inactivation with pharmacologic inhibition of DPP-IV, we developed quantitative mass spectrometric methods that differentiate intact SDF-1α from its inactive form. Using top-down strategy in quantification, we demonstrated the unique advantage of keeping SDF-1α’s two disulfide bridges intact in the analysis. To achieve the optimal sensitivity required for quantification of intact and truncated SDF-1α at endogenous levels in blood, we coupled nano-flow tandem mass spectrometry with antibody-based affinity enrichment. The assay has a quantitative range of 20 pmol/L to 20 nmol/L in human plasma as well as in rhesus monkey plasma. With only slight modification, the same assay can be used to quantify SDF-1α in mice. Using two in vivo animal studies as examples, we demonstrated that it was critical to differentiate intact SDF-1α from its truncated form in the analysis of biomarkers for pharmacologic inhibition of DPP-IV activity. These novel methods enable translational research on suppression of SDF-1 inactivation with DPP-IV inhibition and can be applied to relevant clinical samples in the future to yield new insights on change of SDF-1α levels in disease settings and in response to therapeutic interventions. Figure
? 相似文献
55.
Erica D. Couch Dr. Tyler J. Auvil Prof. Anita E. Mattson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(27):8283-8287
The enhanced catalytic activity of difluoroboronate ureas proved to be essential as an acidity amplifier to promote metal‐free O?H and S?H insertion reactions of α‐aryldiazoacetates in high yield. This methodology was found to be generally applicable to a broad substrate scope and presents a conceptually new approach for organocatalytic diazo insertion reactions. Mechanistic investigations suggest that the reaction pathway involves a urea‐induced protonation of the α‐aryldiazoester. 相似文献
56.
ukasz Balewski Franciszek Sczewski Patrick J. Bednarski Lisa Wolff Anna Nadworska Maria Gdaniec Anita Kornicka 《Molecules (Basel, Switzerland)》2020,25(24)
The appropriate 1-arylhydrazinecarbonitriles 1a–c are subjected to the reaction with 2-chloro-4,5-dihydro-1H-imidazole (2), yielding 7-(4,5-dihydro-1H-imidazol-2-yl)-2-aryl-6,7-dihydro-2H-imidazo[2,1-c][1,2,4]triazol-3(5H)-imines 3a–c, which are subsequently converted into the corresponding amides 4a–e, 8a–c, sulfonamides 5a–n, 9, ureas 6a–I, and thioureas 7a–d. The structures of the newly prepared derivatives 3a–c, 4a–e, 5a–n, 6a–i, 7a–d, 8a–c, and 9 are confirmed by IR, NMR spectroscopic data, as well as single-crystal X-ray analyses of 5e and 8c. The in vitro cytotoxic potency of these compounds is determined on a panel of human cancer cell lines, and the relationships between structure and antitumor activity are discussed. The most active 4-chloro-N-(2-(4-chlorophenyl)-7-(4,5-dihydro-1H-imidazol-2-yl)-6,7-dihydro-2H-imidazo[2,1-c][1,2,4]triazol-3(5H)-ylidene)benzamide (4e) and N-(7-(4,5-dihydro-1H-imidazol-2-yl)-2-(p-tolyl)-6,7-dihydro-2H-imidazo[2,1-c][1,2,4]triazol-3(5H)-ylidene)-[1,1′-biphenyl]-4-sulfonamide (5l) inhibits the growth of the cervical cancer SISO and bladder cancer RT-112 cell lines with IC50 values in the range of 2.38–3.77 μM. Moreover, N-(7-(4,5-dihydro-1H-imidazol-2-yl)-2-phenyl-6,7-dihydro-2H-imidazo[2,1-c][1,2,4]triazol-3(5H)-ylidene)-4-phenoxybenzenesulfonamide (5m) has the best selectivity towards the SISO cell line and induces apoptosis in this cell line. 相似文献
57.
Lina Hudhud David R. Chisholm Andrew Whiting Anita Steib Krisztina Pohczky Angla Kecsks va Szke Zsuzsanna Helyes 《Molecules (Basel, Switzerland)》2022,27(3)
All-trans-retinoic acid (ATRA), the active metabolite of vitamin A, plays a pivotal role in cell differentiation, proliferation and embryonic development. It is an effective therapy for dermatological disorders and malignancies. ATRA is prone to isomerization and oxidation, which can affect its activity and selectivity. Novel diphenylacetylene-based ATRA analogues with increased stability can help to overcome these problems and may offer significant potential as therapeutics for a variety of cancers and neurodegenerative diseases, including amyotrophic lateral sclerosis. Here, we investigated the effects of these retinoids on cell viability and genotoxicity in the widely used model system of the rapidly proliferating Chinese hamster ovary cell line. DC360 is a fluorescent ATRA analogue and DC324 is a non-active derivative of DC360. EC23, DC525, DC540, DC645, and DC712 are promising analogues with increased bioactivity. The cytotoxic activity of the compounds was evaluated by ATP assay and DNA damage was tested by comet assay. No cytotoxicity was observed in the 10−6–10−5 M concentration range. All compounds induced DNA migration similar to ATRA, but DC324, DC360 and EC23 did so to a greater extent, particularly at higher concentrations. We believe that retinoid receptor-independent genotoxicity is a general characteristic of these compounds; however, further studies are needed to identify the molecular mechanisms and understand their complex biological functions. 相似文献
58.
Poulomi Majumdar Anita Pati Rajani K. Behera Ajaya Kumar Behera 《Journal of heterocyclic chemistry》2013,50(3):703-712
A Cannizzaro‐type reaction of tetrahydro‐5(1H)‐quinolinones with para substituted benzaldehydes in the presence of a base formed the corresponding quinoline and aryl methanol rather than arylidene derivatives because of the oxidation of tetrahydroquinoline and reduction of benzaldehydes as a result of unprecedented hydride transfer from tetrahydroquinoline to arylaldehydes. The reaction proceeds best with the participation of substituents with +M effect in substrate molecule. 相似文献
59.
N1-Hydroxy-2,4,5-trisubstituted imidazoles were synthesized starting from 1,2-diketones. The crystal structure of 4,5-dimethyl-2-(3-nitrophenyl)-1H-imidazol-1-ol has been determined. An unusual intermolecular hydrogen bonding through the association of water molecule has been reported. These imidazole derivatives can be thought of as the organic precursor for the synthesis of zinc oxide nano particles. 相似文献
60.
Fitria Rahmawati Triana Kusumaningsih Anita M. Hapsari Aris Hastuti 《Chemical Papers》2010,64(5):557-565
TiO2 film was synthesized by means of the chemical bath deposition (CBD) method from TiCl4 as a precursor and surfactant cetyl trimethyl ammonium bromide (CTAB) as a linking and assembling agent of the titanium hydroxide
network on a graphite substrate. Ag and Cu were loaded on the TiO2 film by means of electrodeposition at various applied currents. Photoelectrochemical testing on the composite of Ag-TiO2/G and Cu-TiO2/G was used to define the composite for Escherichia coli-contaminated water disinfection. Disinfection efficiency and the rate of disinfection of E. coli-contaminated water with Ag-TiO2/G as a catalyst was higher than that observed for Cu-TiO2/G in all disinfection methods including photocatalysis (PC), electrocatalysis (EC), and photoelectrocatalysis (PEC). The
highest rate constant was achieved by the PEC method using Ag-TiO2/G, k was 6.49 × 10−2 CFU mL−1 min−1. Effective disinfection times of 24 h (EDT24) and 48 h (EDT48) were achieved in all methods except the EC method using Cu-TiO2/G. 相似文献