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排序方式: 共有134条查询结果,搜索用时 15 毫秒
21.
Exposure risk assessment of uranium intake of the milk products from the region of Pernambuco,Brazil
dos Santos Amaral Romilton dos Santos Júnior José Araújo da Silva Aquino Fabiana de Albuquerque Amaral Bruno Fernández Zahily Herrero Bezerra Mariana Brayner Cavalcanti Freire da Silva Arykerne Nascimento Casado dos Santos Djalma Cordeiro do Nascimento Santos Josineide Marques da Silva Alberto Antônio de Barros Correia Filipe Lopes 《Journal of Radioanalytical and Nuclear Chemistry》2019,319(3):927-935
Journal of Radioanalytical and Nuclear Chemistry - Haloperidol (HP) is a dopamine blocking agent. HP was radiolabeled with 125I using direct electrophilic substitution. Different HP formulations... 相似文献
22.
Pedro Henrique Cavalcanti Franco Saulo Fehelberg Pinto Braga Renata Barbosa de Oliveira Isabela Costa César 《Magnetic resonance in chemistry : MRC》2020,58(1):97-105
Quantitative nuclear magnetic resonance (qNMR) is an analytical technique that offers numerous advantages in pharmaceutical applications including minimum sample preparation and rapid data collection times with no need for response factor corrections, being a powerful tool for assaying drug content in both drug discovery and early drug development. In the present work, we have applied qNMR, using both the internal standard and the electronic reference to access in vivo concentrations 2 calibration methods, to assess the purity of RI76, a novel antifungal drug candidate. NMR acquisition and processing parameters were optimized in order to obtain spectra with intense, well-resolved signals of completely relaxed nuclei. The analytical method was validated following current guidelines, demonstrating selectivity, linearity, accuracy, precision, and robustness. The calibration approaches were statistically compared, and no significant difference was observed when comparing the obtained results and their dispersion in terms of relative standard deviation. The proposed qNMR method may, therefore, be used for both qualitative and quantitative assessments of RI76 in early drug development and for characterization of this compound. 相似文献
23.
Marília Cavalcanti Coriolano Cristiane Moutinho Lagos de Melo Flávio de Oliveira Silva Giuliana Viegas Schirato Camila Souza Porto Paulo Jorge Parreira dos Santos Maria Tereza dos Santos Correia Ana Lúcia Figueiredo Porto Ana Maria dos Anjos Carneiro-Leão Luana Cassandra Breitenbach Barroso Coelho 《Applied biochemistry and biotechnology》2014,172(5):2682-2693
Parkia pendula seed lectin was used to treat cutaneous wounds of normal and immunocompromised mice, inducing cicatrization. Methotrexate (0.8 mg/kg/week) was used as immunosuppressive drug. Wounds were produced in the dorsal region (1 cm2) of female albino Swiss mice (Mus musculus), health and immunocompromised. Wounds were daily topically treated with 100 μL of the following solutions: (1) control (NaCl 0.15 M), (2) control Im (0.15 M NaCl), (3) P. pendula seed lectin (100 μg/mL), and (4) P. pendula seed lectin Im (100 μg/mL). Clinical evaluation was performed during 12 days. Biopsies for histopathology analysis and microbiological examinations were carried out in the second, seventh, and 12th days. The presence of edema and hyperemia was observed in all groups during inflammatory period. The first crust was detected from the second day, only in the groups treated with P. pendula seed lectin. Microbiological analysis of wounds from day 0 to day 2 did not show bacterium at P. pendula seed lectin group; however, Staphylococcus sp. was detected every day in the other groups. The lectin markedly induced a total wound closing at P. pendula seed lectin and P. pendula seed lectin Im groups on 11th day of evolution. The present study suggests that P. pendula seed lectin is a biomaterial potential to show pharmacological effect in the repair process of cutaneous wounds. 相似文献
24.
Josepha Yohanna de Jesus Eliane Santos de Carvalho Dantas Mairim Russo Serafini Paula dos Passos Menezes Juliana Cordeiro Cardoso Ricardo Luiz Cavalcanti Albuquerque-Jr Jivaldo do Rosário Matos Juliana Ferreira de Oliveira Irwin Rose Alencar de Menezes Francilene Amaral da Silva Adriano Antunes de Souza Araújo 《Journal of Thermal Analysis and Calorimetry》2016,123(3):2003-2012
25.
We introduce a method to resolve a symplectic orbifold(M,ω) into a smooth symplectic manifold . Then we study how the formality and the Lefschetz property of are compared with that of (M,ω). We also study the formality of the symplectic blow-up of (M,ω) along symplectic submanifolds disjoint from the orbifold singularities. This allows us to construct the first example of a simply connected compact symplectic manifold of dimension 8 which satisfies the Lefschetz property but is not formal, therefore giving a counter-example to a conjecture of Babenko and Taimanov. 相似文献
26.
De-Paula JC Bueno LB Cavalcanti DN Yoneshigue-Valentin Y Teixeira VL 《Molecules (Basel, Switzerland)》2008,13(6):1253-1262
The crude extract of the Brazilian brown alga Dictyota crenulata was analyzed by NMR spectroscopy and HRGC-MS techniques. Seven diterpenes were identified: pachydictyol A, dictyodial, 4beta-hydroxydictyodial A, 4beta-acetoxydictyodial A, isopachydictyol A, dictyol C and dictyotadiol. Xeniane diterpenes have previously been found in D. crenulata from the Pacific Ocean. The results characterize D. crenulata as a species that provides prenylated guaiane (group I) and xeniane diterpenes (group III), thus making it a new source of potential antiviral products. 相似文献
27.
Guimarães RL Lima DJ Barros ME Cavalcanti LN Hallwass F Navarro M Bieber LW Malvestiti I 《Molecules (Basel, Switzerland)》2007,12(9):2089-2105
The aqueous tin-mediated Barbier reaction affords good to excellent yields and moderate syn diastereoselectivity under basic and acidic conditions. The high yields and stereoselectivity observed in the case of o-substituted aldehydes suggest a cyclic organotin intermediate or transition state in K2HPO4 solution. A practical and efficient aqueous tin allylation of methoxy- and hydroxybenzaldehydes can be carried out in HCl solution in 15 minutes to afford the corresponding homoallylic alcohols in high yields. Aliphatic aldehydes give moderate to excellent yields with reaction times ranging from 30 to 60 minutes. Under these conditions, crotylation gives exclusively the gamma-product and the syn isomer is formed preferentially. For 2-methoxybenzaldehyde, an equilibration of the isomers to a syn/anti ratio of 1:1 can be observed after several hours. Control experiments with radical sources or scavengers give no support for radical intermediates. NMR studies suggest a mechanism involving an organotin intermediate. The major organotin species formed depends on the reaction medium and the reaction time. The use of acidic solution reduces the reaction times, due to the acceleration of the formation of the allyltin(IV) species. 相似文献
28.
Cavalcanti ED Maciel FM Villeneuve P Lago RC Machado OL Freire DM 《Applied biochemistry and biotechnology》2007,137(1-12):57-65
The influence of several factors on the hydrolytic activity of lipase, present in the acetone powder from dormant castor seeds (Ricinus communis) was evaluated. The enzyme showed a marked specificity for short-chain substrates. The best reaction conditions were an acid medium, Triton X-100 as the emulsifying agent and a temperature of 30 degrees C. The lipase activity of the acetone powder of different castor oil genotypes showed great variability and storage stability of up to 90%. The toxicology analysis of the acetone powder from genotype Nordestina BRS 149 showed a higher ricin (toxic component) content, a lower 2S albumin (allergenic compound) content, and similar allergenic potential compared with untreated seeds. 相似文献
29.
Vytria Piscitelli Cavalcanti Smail Aazza Suzan Kelly Vilela Bertolucci Joo Pedro Miranda Rocha Adriane Duarte Coelho Altino Júnior Mendes Oliveira Laís Campelo Mendes Maysa Mathias Alves Pereira Ludmila Caproni Morais Moacir Rossi Forim Moacir Pasqual Joyce Dria 《Molecules (Basel, Switzerland)》2021,26(19)
Garlic is a health promoter that has important bioactive compounds. The bioactive extraction is an important step in the analysis of constituents present in plant preparations. The purpose of this study is to optimize the extraction with the best proportion of solvents to obtain total phenolic compounds (TPC) and thiosulfinates (TS) from dried garlic powder, and evaluate the antioxidant activities of the optimized extracts. A statistical mixture simplex axial design was used to evaluate the effect of solvents (water, ethanol, and acetone), as well as mixtures of these solvents, after two ultrasound extraction cycles of 15 min. Results showed that solvent mixtures with a high portion of water and pure water were efficient for TPC and TS recovery through this extraction procedure. According to the regression model computed, the most significant solvent mixtures to obtain high TPC and TS recovery from dried garlic powder are, respectively, the binary mixture with 75% water and 25% acetone and pure water. These optimized extracts presented oxygen radical absorbance capacity. Pure water was better for total antioxidant capacity, and the binary mixture of water–acetone (75:25) was better for DPPH scavenging activity. These optimized extracts can be used for industrial and research applications. 相似文献
30.
Lidia Moreira Lima Tiago Fernandes da Silva Carlos Eduardo da Silva Monteiro Cristiane Aparecida-Silva Walfrido Bispo Júnior Aline Cavalcanti de Queiroz Magna Suzana Alexandre-Moreira Gisele Zapata-Sudo Eliezer J. Barreiro 《Molecules (Basel, Switzerland)》2021,26(16)
Acylhydrazones are still an important framework to the design of new bioactive compounds. As treatment of chronic pain represents a clinical challenge, we decided to modify the structure of LASSBio-1514 (1), previously described as anti-inflammatory and analgesic prototype. Applying the homologation as a strategy for molecular modification, we designed a series of cyclopentyl- (2a–e), cyclobutyl- (3a–e), and cyclopropylacylhydrazones (4a–e) that were synthetized and evaluated in murine models of inflammation and pain. A comparison of their in silico physicochemical and drug-like profile was conducted, as well as their anti-inflammatory and analgesic effect. Compounds 4a (LASSBio-1755) and 4e (LASSBio-1757) displayed excellent in silico drug-like profiles and were identified as new analgesic lead-candidates in acute and chronic model of pain, through oral administration. 相似文献