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61.
Kassi E Papoutsi Z Fokialakis N Messari I Mitakou S Moutsatsou P 《Journal of agricultural and food chemistry》2004,52(23):6956-6961
To prevent bone loss that occurs with increasing age, nutritional and pharmacological factors are needed. Traditional therapeutic agents (selective estrogen receptor modulators or SERMs, biphosphonates, calcitonin) may have serious side effects or contraindications. In an attempt to find food components potentially acting as SERMs, we submitted four plant aqueous extracts derived from Greek flora (Sideritis euboea, Sideritis clandestina, Marticaria chamomilla, and Pimpinella anisum) in a series of in vitro biological assays reflective of SERM profile. We examined their ability (a) to stimulate the differentiation and mineralization of osteoblastic cell culture by histochemical staining for alkaline phosphatase and Alizarin Red-S staining, (b) to induce, like antiestrogens, the insulin growth factor binding protein 3 (IGFBP3) in MCF-7 breast cancer cells, and (c) to proliferate cervical adenocarcinoma (HeLa) cells by use of MTT assay. Our data reveal that all the plant extracts studied at a concentration range 10-100 microg/mL stimulate osteoblastic cell differentiation and exhibit antiestrogenic effect on breast cancer cells without proliferative effects on cervical adenocarcinoma cells. The presence of estradiol inhibited the antiestrogenic effect induced by the extracts on MCF-7 cells, suggesting an estrogen receptor-related mechanism. In conclusion, the aqueous extracts derived from Sideritis euboea, Sideritis clandestina, Marticaria chamomilla, and Pimpinella anisum may form the basis to design "functional foods" for the prevention of osteoporosis. 相似文献
62.
In plants, zinc is commonly found bound to proteins. In barley (Hordeum vulgare), major storage proteins are alcohol‐soluble prolamins known as hordeins, and some of them have the potential to bind or store zinc. 65Zn overlay and blotting techniques have been widely used for detecting zinc‐binding protein. However, to our knowledge so far this zinc blotting assay has never been applied to detect a prolamin fraction in barley grains. A radioactive zinc (65ZnCl2) blotting technique was optimized to detect zinc‐binding prolamins, followed by development of an easy‐to‐follow nonradioactive colorimetric zinc blotting method with a zinc‐sensing dye, dithizone. Hordeins were extracted from mature barley grain, separated by SDS‐PAGE, blotted on a membrane, renatured, overlaid, and probed with zinc; subsequently, zinc‐binding specificity of certain proteins was detected either by autoradiography or color formation. The dithizone staining method gave similar reproducibility to the radioactive blotting. The detected zinc‐binding protein was identified as B‐hordein by Western blotting. 相似文献
63.
OBJECTIVE: To assess the sedative and cardiopulmonary effects of medetomidine and xylazine and their reversal with atipamezole in calves. ANIMALS: 25 calves. PROCEDURES: A 2-phase (7-day interval) study was performed. Sedative characteristics (phase I) and cardiopulmonary effects (phase II) of medetomidine hydrochloride and xylazine hydrochloride administration followed by atipamezole hydrochloride administration were evaluated. In both phases, calves were randomly allocated to receive 1 of 4 treatments IV: medetomidine (0.03 mg/kg) followed by atipamezole (0.1 mg/kg; n = 6), xylazine (0.3 mg/kg) followed by atipamezole (0.04 mg/kg; 7), medetomidine (0.03 mg/kg) followed by saline (0.9% NaCl; 6) solution (10 mL), and xylazine (0.3 mg/kg) followed by saline solution (10 mL; 6). Atipamezole or saline solution was administered 20 minutes after the first injection. Cardiopulmonary variables were recorded at intervals for 35 minutes after medetomidine or xylazine administration. RESULTS: At the doses evaluated, xylazine and medetomidine induced a similar degree of sedation in calves; however, the duration of medetomidine-associated sedation was longer. Compared with pretreatment values, heart rate, cardiac index, and PaO(2) decreased, whereas central venous pressure, PaCO(2), and pulmonary artery pressures increased with medetomidine or xylazine. Systemic arterial blood pressures and vascular resistance increased with medetomidine and decreased with xylazine. Atipamezole reversed the sedative and most of the cardiopulmonary effects of both drugs. CONCLUSIONS AND CLINICAL RELEVANCE: At these doses, xylazine and medetomidine induced similar degrees of sedation and cardiopulmonary depression in calves, although medetomidine administration resulted in increases in systemic arterial blood pressures. Atipamezole effectively reversed medetomidine- and xylazine-associated sedative and cardiopulmonary effects in calves. 相似文献
64.
65.
OBJECTIVE: To determine the effect of a porcine-derived small intestinal submucosa product (PSIS) on healing time, epithelialization, angiogenesis, contraction, and inflammation of wounds with exposed bone on the distal aspect of the limbs of dogs. STUDY DESIGN: Prospective, controlled, experimental study. ANIMAL POPULATION: 10 young adult, purpose-bred, male Beagles. METHODS: Small wounds with exposed bone were created on the lateral aspect of metatarsal V and the medial aspect of metatarsal II on both hindlimbs. Three sheets of PSIS were sutured into the wounds of the treated limb, and the other limb served as a control. On day 10, punch biopsies of the medial metatarsal wounds were collected and were evaluated microscopically after routine hematoxylin and eosin and phosphotungstic acid hematoxylin (PTAH) staining. The lateral metatarsal wounds were evaluated by planimetry and laser Doppler perfusion imaging on days 7, 14, and 21. Time until complete wound healing was also recorded. The level of significance was set at P < or =.05 for all statistical analyses. RESULTS: Laser Doppler perfusion measurements were significantly higher in control wounds on day 7, but no differences were noted on days 14 and 21. No significant differences in planimetric values, histopathologic appearance, or time until complete wound healing were noted among treated and control groups. CONCLUSIONS: No objective differences in healing were noted between control wounds and wounds treated with PSIS. CLINICAL RELEVANCE: There appears to be no contraindication to the use of PSIS on clean wounds with exposed bone on the distal limbs of dogs. However, our objective data provides no evidence that this product affects epithelialization, contraction, or time to complete healing in wounds with exposed bone. 相似文献
66.
Zoonotic West Nile virus (WNV) circulates in natural transmission cycles involving certain mosquitoes and birds, horses, humans, and a range of other vertebrates are incidental hosts. Clinical infections in humans can range in severity from uncomplicated WNV fever to fatal meningoencephalitis. Since its introduction to the Western Hemisphere in 1999, WNV had spread across North America, Central and South America and the Caribbean, although the vast majority of severe human cases have occurred in the United States of America (USA) and Canada. By 2002-2003, the WNV outbreaks have involved thousands of patients causing severe neurologic disease (meningoencephalitis and poliomyelitis-like syndrome) and hundreds of associated fatalities in USA. The purpose of this review is to present recent information on the epidemiology and pathogenicity of WNV since its emergence in North America. 相似文献
67.
Sjolund M. Jennifer Arnsdorf Yvonne M. Carnegie Mairi Fornefeld Eva Will Torsten 《植物病害和植物保护杂志》2019,126(1):89-92
Journal of Plant Diseases and Protection - Psyllids are small, phloem-feeding insects. Several species are vectors of economically important pathogens, such as ‘Candidatus Liberibacter... 相似文献
68.
Alexander Valverde DVM DVSc DACVA Giacomo Gianotti DVM Eva Rioja DVM PhD DVSc DACVA Amanda Hathway RVT 《Journal of Veterinary Emergency and Critical Care》2011,21(4):328-334
Objective – To compare the determination of cardiac output (CO) via arterial pulse pressure waveform analysis (FloTrac/Vigileo) versus lithium dilution method. Design – Prospective study. Setting – University teaching hospital. Animals – Six adult dogs. Interventions – Dogs were instrumented for CO determinations using lithium dilution (LiDCO) and FloTrac/Vigileo methods. Direct blood pressure, heart rate, arterial blood gases, and end‐tidal isoflurane (ETIso) and CO2 concentrations were measured throughout the study while CO was manipulated with different depth of anesthesia and rapid administration of isotonic crystalloids at 60 mL/kg/h. Measurements and Main Results – Baseline CO measurements were obtained at 1.3% ETIso and were lowered by 3% ETIso. Measurements were obtained in duplicate or triplicate with LiDCO and averaged for comparison with corresponding values measured continuously with the FloTrac/Vigileo method. For 30 comparisons between methods, a mean bias of ?100 mL/kg/min and 95% limits of agreement between ?311 and +112 mL/kg/min (212 mL/kg/min) was determined. The mean (mL/kg/min) of the differences of LiDCO?Vigileo=62.0402+?0.8383 × Vigileo, and the correlation coefficient (r) between the 2 methods 0.70 for all CO determinations. The repeatability coefficients for the individual LiDCO and FloTrac/Vigileo methods were 187 and 400 mL/kg/min, respectively. Mean LiDCO and FloTrac/Vigileo values from all measurements were 145 ± 68 mL/kg/min (range, 64–354) and 244 ± 144 mL/kg/min (range, 89–624), respectively. The overall mean relative error was 48 ± 14%. Conclusion – The FloTrac/Vigileo overestimated CO values compared with LiDCO and the relative error was high, which makes this method unreliable for use in dogs. 相似文献
69.
Determination of beta-lactams in milk using a surface plasmon resonance-based biosensor 总被引:3,自引:0,他引:3
Gustavsson E Degelaen J Bjurling P Sternesjö A 《Journal of agricultural and food chemistry》2004,52(10):2791-2796
Two surface plasmon resonance (SPR)-based biosensor assays for detection of beta-lactam antibiotics in milk are reported. The assays are based on the enzymatic activity of a carboxypeptidase converting a 3-peptide into a 2-peptide, a reaction that is inhibited in the presence of beta-lactams. Antibodies were used to measure either the amount of formed enzymatic product or the amount of remaining enzymatic substrate. Both assays detected different beta-lactams at or below European maximum residue limits (MRLs), and the detection limit for penicillin G was 1.2 microg/kg and 1.5 microg/kg for the 2- and 3-peptide assays, respectively. The precision (CV) was < 5%, both within and between assays at the penicillin G MRL (4 microg/kg). The biosensor results obtained upon analysis of incurred milk samples were compared with results obtained by liquid chromatography (HPLC), and the method agreements were, in general, good. 相似文献
70.
Javier Madrigal Eva Marino Mercedes Guijarro Carmen Hernando Carmen Díez 《Annals of Forest Science》2012,69(3):387-397