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61.
Lutze-Wallace C Turcotte C Glover G Cousins D Bell J Berlie-Surujballi G Barbeau Y Randall G 《The Canadian veterinary journal. La revue veterinaire canadienne》2006,47(10):1011-1013
A Mycobacterium tuberculosis complex organism was isolated from a zoo resident rock hyrax (Procavia capensis) imported into Canada from South Africa. The strain was identified biochemically as Mycobacterium microti. The spoligotype pattern obtained for this isolate was found to be rare. This represents the first report of isolation and spoligotyping of M. microti in North America. 相似文献
62.
Filippo Maggi Massimo Bramucci Cinzia Cecchini Maria M. Coman Alberto Cresci Gloria Cristalli Giulio Lupidi Fabrizio Papa Luana Quassinti Gianni Sagratini Sauro Vittori 《Fitoterapia》2009,80(6):313-319
Essential oil from flowers (FL) and vegetative parts (VP) of Achillea ligustica (Asteraceae), naturalized after cultivation in central Italy, was investigated by GC–FID and GC–MS. The most abundant components were linalool, viridiflorol, β-pinene, 1,8-cineole and terpinen-4-ol. The antioxidant assays (DPPH and ABTS radical scavenging assays, and β-carotene bleaching test) demonstrated a moderate activity of essential oils. The antimicrobial activity was evaluated by the broth micro-dilution method on 6 microbial strains and showed to be quite strong against the cariogenic Gram-positive Streptococcus mutans, suggesting that this essential oil could be a valid candidate for anti-cariogenic formulations. Moderate cytotoxic activity was observed in assays on four tumour cell lines by MTT assay. 相似文献
63.
Gloria E. Arias-Loaiza Erik Beristain-Montiel Sandra Gómez-Arroyo Omar Amador-Muñoz 《Water, air, and soil pollution》2018,229(8):282
Persistent organic pollutants (POPs) are globally dispersed substances considered to have adverse effects on health and ecosystems. Organochlorine pesticides (OCPs) are POPs. OCPs can be collected from the air by passive samplers using polyurethane foam (PUF). POPs in PUF are generally extracted by Soxhlet, considered as reference extraction method. We offer a different methodology approach to extract 16 OCPs from the PUF. This technology extracts, filters, collects the sample and evaporates the solvent, without sample transfer. It is a modification of the ultrasound-assisted extraction micro-scale cell (M-UAE-MSC) previously patented by our group. A full factorial experimental design (23 centred) was used to optimise the extraction conditions. The most desirable conditions were 50 °C, 40% ultrasound potency and 20-min extraction time, two extractions. OCP recoveries ranged from 67 to 110%. OCP recoveries were equivalent by M-UAE-MSC and Soxhlet techniques. The method was not suitable for five OCPs, and further refinement is needed. Method linearity (r2) was ≥?0.98. Limits of detection were observed between 1.2 and 4.6 ng PUF?1, while limits of quantification were found between 3.9 and 15.2 ng PUF?1. The method was applied to determine OCPs collected by PUF passive samplers in Mexico. Endosulfan I was the OCP most frequently observed. The M-UAE-MSC optimised extraction conditions, decreased the extraction time from several hours to less than 1 h and reduced three times the solvent consumption with respect to Soxhlet. This afforded a decrease in the waste generation and a reduction in the OCP-extraction cost up to 80%. The results of this study reveal an efficient and consistent procedure, as well as a simpler, faster, cost-saving and more environmentally friendly method to determine OCPs collected by PUF in passive samplers compared to Soxhlet extraction. 相似文献
64.
Gloria María Molina-Salinas Jorge Bórquez Salvador Said-Fernández Luis Alberto Loyola Alejandro Yam-Puc Pola Becerril-Montes Fabiola Escalante-Erosa Luis Manuel Peña-Rodríguez 《Fitoterapia》2010
Natural azorellane and mulinane diterpenoids show antituberculosis activity, which is increased by methylation of their free carboxyl group. We have systematically investigated the effect of alkylation in this class of diterpenoids and found that the profile of bioactivity is relatively unaffected by the introduction of short alkyl groups, both linear and branched. In this investigation, three semisynthetic diterpenoids, 13 hydroxy-mulin-11-en-20-oic acid n-propyl ester (3) and the n-propyl (19) and n-butyl (20) esters of isomulinic acid, showed the strongest antituberculosis activity (MIC = 6.25 μg/mL) against a drug-resistant strain of Mycobacterium tuberculosis. 相似文献
65.
Barbara Parrino Anna Carbone Gloria Di Vita Cristina Ciancimino Alessandro Attanzio Virginia Spanò Alessandra Montalbano Paola Barraja Luisa Tesoriere Maria Antonia Livrea Patrizia Diana Girolamo Cirrincione 《Marine drugs》2015,13(4):1901-1924
A new series of nortopsentin analogues, in which the imidazole ring of the natural product was replaced by thiazole and the indole unit bound to position 2 of the thiazole ring was substituted by a 7-azaindole moiety, was efficiently synthesized. Two of the new nortopsentin analogues showed good antiproliferative effect against the totality of the NCI full panel of human tumor cell lines (~60) having GI50 values ranging from low micromolar to nanomolar level. The mechanism of the antiproliferative effect of these derivatives, investigated on human hepatoma HepG2 cells, was pro-apoptotic, being associated with externalization of plasma membrane phosphatidylserine and mitochondrial dysfunction. Moreover, the compounds induced a concentration-dependent accumulation of cells in the subG0/G1phase, while confined viable cells in G2/M phase. 相似文献
66.
67.
Gloria Sánchez-Galván Oscar Monroy Jorge Gómez Eugenia J. Olguín 《Water, air, and soil pollution》2008,194(1-4):77-90
Salvinia minima has been reported as a cadmium and lead hyperaccumulator being the adsorption and intracellular accumulation the main uptake mechanisms. However, its physicochemical properties, the effect of metal concentration and the presence of organic and inorganic compounds on its hyperaccumulating capacity are still unknown. Furthermore, the specific adsorption and accumulation mechanisms occurring in the plant are not clear yet. Thus, based on a compartmentalization analysis, a bioadsorption (BAF) and an intracellular accumulation factor (IAF) were calculated in order to differentiate and quantify these two mechanisms. The use of kinetic models allowed predicting the specific type of uptake mechanisms involved. Healthy plants were exposed to five lead concentrations ranging from 0.80?±?0.0 to 28.40?±?0.22 mg Pb2+l?1 in batch systems. A synthetic wastewater, amended with propionic acid and magnesium sulfate, and deionized water were used as media. The BAF and IAF contributed to gain an in-depth insight into the hyperaccumulating lead capacity of S. minima. It is clear that such capacity is mainly due to adsorption (BAF 780–1980) most likely due to its exceptional physico-chemical characteristics such as a very high surface area (264 m2 g?1) and a high content of carboxylic groups (0.95 mmol H+g?1 dw). Chemisorption was predicted as the responsible mechanism according to the pseudo-second order adsorption model. Surprisingly, the ability of S. minima to accumulate the metal into the cells (IAF 57–1007) was not inhibited at concentrations as high as 28.40±0.22 mg Pb2+l?1. 相似文献
68.
Micaela Giani Yoel Genaro Montoyo-Pujol Gloria Peir Rosa María Martínez-Espinosa 《Marine drugs》2021,19(11)
Breast cancer is the leading cause of death among women worldwide. Over the years, oxidative stress has been linked to the onset and progression of cancer. In addition to the classical histological classification, breast carcinomas are classified into phenotypes according to hormone receptors (estrogen receptor—RE—/progesterone receptor—PR) and growth factor receptor (human epidermal growth factor receptor—HER2) expression. Luminal tumors (ER/PR-positive/HER2-negative) are present in older patients with a better outcome. However, patients with HER2-positive or triple-negative breast cancer (TNBC) (ER/PR/HER2-negative) subtypes still represent highly aggressive behavior, metastasis, poor prognosis, and drug resistance. Therefore, new alternative therapies have become an urgent clinical need. In recent years, anticancer agents based on natural products have been receiving huge interest. In particular, carotenoids are natural compounds present in fruits and vegetables, but algae, bacteria, and archaea also produce them. The antioxidant properties of carotenoids have been studied during the last years due to their potential in preventing and treating multiple diseases, including cancer. Although the effect of carotenoids on breast cancer during in vitro and in vivo studies is promising, clinical trials are still inconclusive. The haloarchaeal carotenoid bacterioruberin holds great promise to the future of biomedicine due to its particular structure, and antioxidant activity. However, much work remains to be performed to draw firm conclusions. This review summarizes the current knowledge on pre-clinical and clinical analysis on the use of carotenoids as chemopreventive and chemotherapeutic agents in breast cancer, highlighting the most recent results regarding the use of bacterioruberin from haloarchaea. 相似文献
69.
70.
The fatty acid (FA) composition of nine potentially important forage species was determined (n = 330): red drum (Sciaenops ocellatus), spot (Leiostomus xanthurus), spotted seatrout (Cynoscion nebulosus), striped mullet (Mugil cephalus), pinfish (Lagodon rhomboides), Atlantic croaker (Micropogonias undulatus), star drum (Stellifer lanceolatus), striped anchovy (Anchoa hepsetus), and brief squid (Lolliguncula brevis). Samples were collected from estuarine and nearshore coastal waters around Charleston, South Carolina, USA, from March 2002–February
2003. Twenty-nine of 125 identified FAs were included in multivariate analyses of FA profiles. Despite existing intraspecific
variation, the PRIMER routine analysis of similarity (ANOSIM) indicated each species was distinct, and discriminant function
analysis correctly classified 99.5% of the training data set samples (n = 221) and 98.2% of the validation samples (n = 109). Most species could be characterized by distinctive levels of a suite of FAs. Our results indicated FA profiles can
be used to reliably distinguish even closely related forage species in this southeastern US estuarine ecosystem. The information
gained from this study not only provides insight into the biochemical composition of these important species but also provides
fundamental information to support studies on the feeding ecology of local higher-level predators.
The U.S. Government’s right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged. 相似文献