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11.
Uric Acid Amplifies Aβ Amyloid Effects Involved in the Cognitive Dysfunction/Dementia: Evidences From an Experimental Model In Vitro 下载免费PDF全文
12.
Vanessa Castelli Francesco Melani Claudio Ferri Michele d'Angelo Mariano Catanesi Davide Grassi Elisabetta Benedetti Antonio Giordano Annamaria Cimini Giovambattista Desideri 《Journal of cellular biochemistry》2020,121(12):4862-4869
Oxidative stress is considered the common effector of the cascade of degenerative events in many neurological conditions. Thus, in this paper we tested different nutraceuticals in H2O2 in vitro model to understand if could represent an adjuvant treatment for neurological diseases. In this study, nutraceuticals bacopa, lycopene, astaxanthin, and vitamin B12 were used alone or in combination in human neuronal differentiated SH-SY5Y cells upon hydrogen peroxide-induced injury and neuroprotective, neuronal death pathways were analyzed. The nutraceuticals analyzed were able to protect H2O2 cytotoxic effects, through increasing cell viability and proteins involved in neuroprotection pathways and restoring proteins involved in cell death pathways. On this basis, it is possible to propose the use of these compounds as dietary supplement for the prevention or as adjuvant to the only symptomatic treatments so far available for neurodegenerative diseases. 相似文献
13.
BACKGROUNDS: Recently, potential liver toxicity was discussed with the intake of kava extract preparations (Piper methysticum) as anxiolytic drugs. The aim of this study was to test chronic toxicity in rats by oral application of an ethanolic kava full extract. METHODS: Wistar rats of both sexes were fed 7.3 or 73 mg/kg body weight of ethanolic kava extract for 3 and 6 months. The animals were examined for changes in body weight, hematological and liver parameters, and macroscopical and microscopical histological changes in the major organs. RESULTS: No signs of toxicity could be found. CONCLUSIONS: The results are in accordance with the medical experience regarding the use of kava preparations and the long tradition of kava drinking in the South Pacific island states. Specifically, the results do not back the suspicion of potential liver toxicity. 相似文献
14.
Viviana De Luca Andrea Petreni Vincenzo Carginale Andrea Scaloni Claudiu T. Supuran Clemente Capasso 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):1000
We here report a study on the activation of the ι-class bacterial CA from Burkholderia territorii (BteCAι). This protein was recently characterised as a zinc-dependent enzyme that shows a significant catalytic activity (kcat 3.0 × 105 s−1) for the physiological reaction of CO2 hydration to bicarbonate and protons. Some amino acids and amines, among which some proteinogenic derivatives as well as histamine, dopamine and serotonin, showed efficient activating properties towards BteCAι, with activation constants in the range 3.9–13.3 µM. L-Phe, L-Asn, L-Glu, and some pyridyl-alkylamines, showed a weaker activating effect towards BteCAι, with KA values ranging between 18.4 µM and 45.6 µM. Nowadays, no information is available on active site architecture, metal ion coordination and catalytic mechanism of members of the ι-group of CAs, and this study represents another contribution towards a better understanding of this still uncharacterised class of enzymes. 相似文献
15.
In the first part of this paper we show how inverse problems for differential equations can be solved using the so-called collage method. Inverse problems can be solved by minimizing the collage distance in an appropriate metric space. We then provide several numerical examples in mathematical biology. We consider applications of this approach to the following areas: population dynamics, mRNA and protein concentration, bacteria and amoeba cells interaction, tumor growth. 相似文献
16.
Simona Maria Monti Giuseppina De Simone Nina A. Dathan Martha Ludwig Daniela Vullo Andrea Scozzafava Clemente Capasso Claudiu T. Supuran 《Bioorganic & medicinal chemistry letters》2013,23(6):1626-1630
Several β-carbonic anhydrases (CAs, EC 4.2.1.1) are present in all land plants examined thus far. Here we report the first detailed biochemical characterization of one such isoform, FbiCA 1, from the C4 plant Flaveria bidentis, which was cloned, purified and characterized as recombinant protein. FbiCA 1 has an interesting CO2 hydrase catalytic activity (kcat of 1.2 × 105 and kcat/Km of 7.5 × 106 M?1 × s?1) and was moderately inhibited by most simple/complex inorganic anions. Potent FbiCA 1 inhibitors were also detected, such as trithiocarbonate, diethyldithiocarbamate, sulfamide, sulfamic acid, phenylboronic acid and phenylarsonic acid (KIs in the range of 4–60 μM). Such inhibitors may be used as tools to better understand the role of various β-CA isoforms in photosynthesis. 相似文献
17.
Atilla Akdemir Daniela Vullo Viviana De Luca Andrea Scozzafava Vincenzo Carginale Mosè Rossi Claudiu T. Supuran Clemente Capasso 《Bioorganic & medicinal chemistry letters》2013,23(4):1087-1090
The α-carbonic anhydrase (CA, EC 4.2.1.1) from the extremophilic bacterium Sulfurihydrogenibium azorense (SazCA) was recently shown to be the fastest CA known. Here we investigated this enzyme for its activation with a series of amino acids and amines. The best SazCA activators were d-Phe, l-DOPA, l- and d-Trp, dopamine and serotonin, which showed activation constants in the range of 3–23 nM. l- and d-His, l-Phe, l-Tyr, 2-pyridyl-methylamine and L-adrenaline were also effective activators (KAs in the range of 62–90 nM), whereas d-Dopa, d-Tyr and several heterocyclic amines showed activity in the micromolar range. The good thermal stability, robustness, very high catalytic activity and propensity to be activated by simple amino acids and amines, make SazCA a very interesting candidate for biomimetic CO2 capture processes. 相似文献
18.
Ahmed M. Alafeefy Semra Isik Nabila A. Al-Jaber Daniela Vullo Hatem A. Abdel-Aziz Abdelkader E. Ashour Amani S. Awaad Clemente Capasso Claudiu T. Supuran 《Bioorganic & medicinal chemistry letters》2013,23(12):3570-3575
A series of benzenesulfonamides incorporating cyanoacrylamide moieties (tyrphostine analogs) were assayed as inhibitors of the β-carbonic anhydrase (CA, EC 4.2.1.1) from Saccharomyces cerevisiae, ScCA. Some of these compounds were low nanomolar or subnanomolar ScCA inhibitors and showed selectivity ratios in the range of 4.91–69.86 for inhibiting the yeast enzyme over the offtarget human (h) isoforms hCA I and of 6.46–13.52 for inhibiting ScCA over hCA II. The model organism S. cerevisiae and this particular enzyme may be useful for detecting antifungals with a novel mechanism of action compared to the classical azole drugs to which significant drug resistance emerged. Indeed, some of these sulfonamides inhibited the growth of the yeast with CC50-s in the range of 0.73–6.54 μM. 相似文献
19.
Sonia Del Prete Daniela Vullo Viviana De Luca Vincenzo Carginale Andrea Scozzafava Claudiu T. Supuran Clemente Capasso 《Bioorganic & medicinal chemistry letters》2013,23(14):4067-4071
Carbonic anhydrases (CAs, EC 4.2.1.1) belonging to the γ-class are present in archaea, bacteria and plants but, except the Methanosarcina thermophila enzymes CAM and CAMH, they were poorly characterized so far. Here we report a new such enzyme (PgiCA), the γ-CA from the oral cavity pathogenic bacterium Porphyromonas gingivalis, the main causative agent of periodontitis. PgiCA showed a good catalytic activity for the CO2 hydration reaction, comparable to that of the human (h) isoform hCA I. Inorganic anions such as thiocyanate, cyanide, azide, hydrogen sulfide, sulfamate and trithiocarbonate were effective PgiCA inhibitors with inhibition constants in the range of 41–97 μM. Other effective inhibitors were diethyldithiocarbamate, sulfamide, and phenylboronic acid, with KIs of 4.0–9.8 μM. The role of this enzyme as a possible virulence factor of P. gingivalis is poorly understood at the moment but its good catalytic activity and the possibility to be inhibited by a large number of compounds may lead to interesting developments in the field. 相似文献
20.
The primary structure of syringicin (syr), a new acidic alpha-elicitin, isolated from culture filtrates of Phytophthora syringae, causal agent of citrus fruit rot, has been determined using a combined approch based on Edman degradation and MALDI-MS (TTCTT TQQTA AYVAL VSILS DSSFN QCATD SGYSM LTATA LPTTA QYKLM CASTA CKTMI TKIVS LNAPD CELTV PTSGL VLNVY SYANG FSSTC ASL). Syr has 98 amino acids with a M(r) of 10194.6+/-0.2, which was determined by electrospray ionisation-mass spectrometry (ES-MS) and in agreement with three disulphide bridges, located between Cys3-Cys71, Cys27-Cys56 and Cys51-Cys95. Syr induces a hypersensitive response and electrolyte leakage in tobacco. These are characteristic elicitor properties of the group and in agreement with the molecular mechanism recently proposed for this kind of protein. Finally, its possible applications in biological agriculture and biomedicine are briefly discussed. 相似文献