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971.
Iara Leo Luna de Souza Brbara Cavalcanti Barros Elba dos Santos Ferreira Fernando Ramos Queiroga Luiz Henrique Csar Vasconcelos Lydiane de Lima Tavares Toscano Alexandre Srgio Silva Patrícia Mirella da Silva Fabiana de Andrade Cavalcante Bagnlia Araújo da Silva 《Marine drugs》2022,20(8)
Erectile dysfunction (ED) is the inability to achieve and/or maintain a penile erection sufficient for sexual satisfaction. Currently, many patients do not respond to the pharmacotherapy. The effects of a supplementation with Spirulina platensis, were evaluated in a model of ED induced by hypercaloric diet consumption. Wistar rats were divided into groups fed with standard diet (SD) or hypercaloric diet (HD) and supplemented with this alga at doses of 25, 50 or 100 mg/kg. Experimental adiposity parameters and erectile function were analyzed. In SD groups, Spirulina platensis reduced food intake, final body mass and adiposity index, and increased the total antioxidant capacity (TAC) of adipose tissue. However, no change was observed in erectile function. In the HD group, without Spirulina supplementation, a decrease in food intake was observed, in addition to an increase of final body mass, weight gain, adipose reserves, and adiposity index. Additionally, reduction in the number and increase in the latency of penile erection and adipose malondialdehyde levels, as well as a reduction in TCA was noted. Furthermore, cavernous contractility was increased, and the relaxing response was decreased. Interestingly, these deleterious effects were prevented by the algae at doses of 25, 50 and/or 100 mg/kg. Therefore, the supplementation with S. platensis prevents damages associated to a hypercaloric diet consumption and emerges as an adjuvant the prevention of ED. 相似文献
972.
Mendonça Evânia Galvão Batista Tânia Regina Stein Vanessa Cristina Balieiro Flávia Pereira de Abreu José Renato Pires Marinês Ferreira de Souza Patrícia Aparecida Paiva Luciano Vilela 《New Forests》2020,51(5):801-816
New Forests - The aim of this study was to improve the rooting efficiency of Eucalyptus urophylla clones by in vitro reinvigoration/rejuvenation in two clones (02 and 04) from the breeding program... 相似文献
973.
Gil Martins Laura Ribeiro Ana Candeias‐Mendes Patrícia Diogo Margarida Gamboa Marisa Barata Maria Leonor Cancela Pedro Pouso‐Ferreira Paulo Jorge Gavaia 《Aquaculture Research》2019,50(10):2782-2792
The consolidation of meagre (Argyrosomus regius) in aquaculture requires an understanding and optimization of larval rearing and nutritional conditions. The aim of this study was to analyse the effects of an early introduction of inert diets during larval rearing, on growth performance, digestive enzymes activity and development of skeletal anomalies. This study evaluated the effects of three different timings for the introduction of inert diet during larval rearing: a control group (CTRL) where inert diet was initiated at 14 days after hatching (DAH) and two treatment groups that had an earlier introduction of inert diet at 8 DAH (T1) and 11 DAH (T2). Meagre larvae exhibited similar pancreatic and intestinal enzymatic activities among the different dietary treatments. No differences in the overall prevalence of anomalies were observed between treatments at 25 or 50 DAH, however, a significant reduction was observed in all groups with the transition from larval to juvenile stage. The precocious introduction of inert diet shifted the distribution of vertebral anomalies to a more anterior vertebral column region. Altogether, this study shows that earlier introduction of inert diets in meagre hatcheries can be beneficial for meagre production in aquaculture. 相似文献
974.
Camila N. Boeri Fernando J. Neto da Silva Jorge A. F. Ferreira Jorge M. A. Saraiva Rui S. Moreira 《Journal Of Aquatic Food Product Technology》2013,22(6):551-563
Industrial drying of salted fish is an extremely common practice in the Portuguese industry of codfish processing. The present study aims to obtain sorption isotherms of codfish, which will be useful in designing drying processes and prediction of storage conditions for this product. The equilibrium moisture contents (wet basis) were determined for salted codfish at 15, 18, 20, and 23ºC at relative humidities ranging from 40 to 70%. Experiments were also carried out for fresh codfish at the temperature of 20ºC for the same values of relative humidity. The sorption capacity of codfish decreased with an increase in temperature at constant relative humidity. Thirteen models were used to correlate the experimental data analysis of salted codfish: modified BET, Cauri, Chung-Pfost, modified Chung-Pfost, GAB, modified GAB, Halsey, modified Henderson, Kuhn, Oswin, modified Oswin, Smith, and modified Smith. Based on the mean relative percentage deviation, standard error of estimate, randomness of residual, and coefficient of determination, experimental data were well described by all the models. The equilibrium moisture content of salted codfish was best predicted using the modified GAB model, with a coefficient of determination of 0.99. 相似文献
975.
João Chambel Rúben Pinho Rita Sousa Tânia Ferreira Teresa Baptista Vera Severiano Susana Mendes Rui Pedrosa 《Aquaculture Research》2015,46(7):1582-1589
The efficacy of anaesthetic tricaine methanesulfonate (MS‐222) was evaluated in four freshwater aquarium fish species, Zebrafish (Danio rerio), Guppy (Poecilia reticulata), Discu (Symphysodon discus) and Green swordtail (Xiphophorus helleri). The correct dose of anaesthetic should induce the plane 4 of anaesthesia in less than 180 s, recovery in less than 300 s and must survive when exposed during 30 min to anaesthetic. Fishes were exposed to six concentrations of anaesthetic (75, 100, 125, 150, 200 and 250 mg L?1) and the time of fish reaching plane 4 of anaesthesia, post exposure recovery, and the percentage of survival when fish were subject to 30 min in the anaesthetic were recorded. The optimal doses varied according to the species: D. rerio – 75, 100 and 125 mg L?1, P. reticulata – 125, 150 and 200 mg L?1, S. discus – 75 and 100 mg L?1 and X. helleri – 125 and 150 mg L?1. The induction time generally decreased significantly with increasing concentration of MS‐222 for all of the species evaluated. The recovery time had a tendency to increase with the increase of the MS‐222 concentration for D. rerio, P. reticulata and S. discus. On the other hand, X. helleri recovery time decreased with the increase of MS‐222 concentration. MS‐222 proved to be effective in anaesthesia for all the freshwater ornamental species studied. The main results clearly show that the optimal dose to anesthetize is fish species dependent and it is completely wrong to extrapolate optimal anaesthetic concentrations between different species. 相似文献
976.
977.
A.S. Capucho L. Zambolim H.S.S. Duarte D.F. Parreira P.A. Ferreira F.E. Lanza R.V. Costa C.R. Casela L.V. Cota 《Crop Protection》2010
The main objective of this research is to determine the influence of leaf position on corn plants with white spot caused by Pantoea ananatis, which better represents the infection on the whole plant. A diagrammatic scale to quantify the severity of the disease was elaborated and validated. For scale elaboration, the minimal and maximal limits of the disease severity observed in the field were considered, and intermediate levels followed logarithmic increments according to the Weber–Fechner stimulation law. The scale has nine classes: 0.1, 1, 2, 4, 8, 16, 24, 32 and 64%. For scale evaluation, a severity evaluation for white spot was performed by 10 raters with no experience in disease evaluation. Initially, severity estimation was performed without a scale for 41 leaves with different levels of severity. Afterward, the same raters used the proposed diagrammatic scale. Through linear regression to compare the actual and estimate severity values, the raters’ accuracy and precision were analyzed. Satisfactory accuracy and precision were achieved when estimation was performed with a diagrammatic scale. To determine the best leaf disease severity evaluation, correlation and regression analyses were performed with 25 plants of five genotypes, for a total of 284 leaves analyzed. Results analysis leads us to conclude that the severity of white spot on corn plants significantly correlates with the disease mean severity of leaves 0 and -1, i.e., a leaf of the corn ear and the one immediately below it. This scale provided good levels of accuracy and precision (a mean R2 of 94%), with errors concentrating around 10%. Raters presented increased reproducibility (R2 > 90% in 82% of cases) of severity estimates. The proposed diagrammatic scale is considered adequate to estimate the severity of white spot in corn for germplasm evaluations, for epidemiological studies and for evaluation of control strategies for this disease. 相似文献
978.
Laurício Endres Celene A. Câmara Vilma M. Ferreira José V. Silva 《Agroforestry Systems》2010,78(3):287-298
The objective of this study was to evaluate the effect of nursery shading on the Yellow-ipe seedling (Tabebuia chrysotricha) growth, photosynthesis, and photosynthetic acclimation after being transferred into direct sunlight. The Yellow-ipe seedlings
were grown under 0, 50, 70 and 95% shade. At the 134th day of sowing, leaf gas exchange and chlorophyll were measured under
current growth shading, after exposure to 15 min and two day full sunlight. With the increase of shading, the Yellow-ipe seedlings
allocated more biomass to the stem and leaves and less to the roots, and there was an increase in the leaf area ratio and
specific leaf area. In relation to 0% of shading there was a increase of 211% in stem, 116% in leaf, and a reduction of 200%
in roots biomass when seedling were grown under 95% of shading. The total biomass accumulation had a high correlation with
collar diameter (r = 0.96). More than 70% of the shading reduced the photosynthesis, and after transferring the seedlings into full sunlight,
more than 50% of the shading induced a reduction in chlorophyll, stomatal conductance, photosynthesis and instantaneous carboxylation
efficiency, suggesting the presence of a photoinhibition process. The Yellow-ipe seedling growth under nursery conditions
should not be done under more than 50% shading, which may result in the lower seedling quality and poorer acclimation to transplantation,
particularly to severe degraded areas with direct sunlight. The species can be used for recovering from totally devastated
forest areas to initial recovery when full canopy are forming. 相似文献
979.
Antonio H.H. Minervino Raimundo A. Barrêto Júnior Frederico A.M.L. Rodrigues Rodrigo N.F. Ferreira Leonardo F. Reis Selwyn A. Headley Enrico L. Ortolani 《Research in veterinary science》2010,88(3):519-522
Four 1.5-year-old, male, Murrah buffalos were maintained during eight months without direct solar exposure during a study of copper toxicosis. Four days after solar exposure, all buffalos presented clinical manifestations consistent with acute photosensitization, including anorexia, apathy, loss of body weight, and generalized cutaneous lesions. Gross lesions were characterized by severe erythema, localized edema, fissures, tissue necrosis, gangrene and crust formation with serous exudation. Liver copper concentration was evaluated, and cutaneous biopsies were taken when clinical signs were evident. The liver copper concentration before solar exposure was increased in all animals. Histopathologic examination of the skin revealed hepatogenous photosensitization characterized by parakeratotic hyperkeratosis, acantholysis, degeneration of squamous epithelial cells, epidermal necrosis with atrophy of sweat glands, and multifocal superficial and deep dermal edema. These findings suggest that asymptomatic accumulation of copper within the liver might have induced hepatic insufficiency thereby resulting in secondary photosensitization when these buffalos were exposed to sunlight. 相似文献
980.
盐溶液如CCA和CCB是用来防治竹子腐烂、虫蛀和白蚁的主要化学品。通过测定竹秆中化学品的总量,评价了这些方法的有效性。将大耳竹劈成条,浸泡在10%的CCB溶液中(31.75的铬,13%的铜和5.25%的硼),并评价了从竹条到浸入溶液之间的时间的影响。利用电子显微镜确定了化学品的可追朔性。结果证实,铬和铜氧化随着竹解剖分子不均匀分布。 相似文献