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111.
Background
Heifers not used as breeding stock are often implanted with steroids to increase growth efficiency thereby altering hormone profiles and potentially changing the environment in which ovarian follicles develop. Because bovine granulosa cell culture is a commonly used technique and often bovine ovaries are collected from abattoirs with no record of implant status, the objective of this study was to determine if the presence of an implant during bovine granulosa cell development impacts follicle stimulating hormone-regulated steroidogenic enzyme expression. Paired ovaries were collected from 16 feedlot heifers subjected to 1 of 3 treatments: non-implanted (n?=?5), Revalor 200 for 28 d (n?=?5), or Revalor 200 for 84 d (n?=?6). Small follicle (1 to 5 mm) granulosa cells were isolated from each pair and incubated with phosphate buffered saline (n?=?16) or 100 ng/mL follicle stimulating hormone (n?=?16) for 24 h.Results
Granulosa cells of implanted heifers treated with follicle stimulating hormone produced medium concentrations of progesterone similar (P?=?0.22) to non-implanted heifers, while medium estradiol concentrations were increased (P?<?0.10) at 28 and 84 d compared to non-implanted heifers indicating efficacy of treatment. Additionally, real-time PCR analysis in response to follicle stimulating hormone treatment demonstrated a decrease in steroidogenic acute regulatory protein (P?=?0.05) mRNA expression in heifers implanted for 84 d and an increase in P450 side chain cleavage mRNA in granulosa cells of heifers implanted for 28 (P?<?0.10) or 84 d (P?<?0.05) compared to non-implanted females. However, no difference in expression of 3-beta-hydroxysteroid dehydrogenase (P?=?0.57) and aromatase (P?=?0.23) were demonstrated in implanted or non-implanted heifers.Conclusions
These results indicate follicles which develop in the presence of high concentrations of androgenic and estrogenic steroids via an implant tend to demonstrate an altered capacity to respond to follicle stimulating hormone stimulation. Thus, efforts should be made to avoid the use of implanted heifers to study steroidogenesis in small follicle granulosa cell culture systems. 相似文献112.
Grazziotin AL Santos AP Guimaraes AM Mohamed A Cubas ZS de Oliveira MJ dos Santos LC de Moraes W Vieira RF Donatti L de Barros Filho IR Biondo AW Messick JB 《Veterinary microbiology》2011,152(3-4):415-419
Hemotrophic mycoplasmas (hemoplasmas) are bacteria that attach to red blood cells of mammals, leading to acute and/or subclinical disease in infected animals. It has been suggested that Mycoplasma ovis, a hemoplasma that infects sheep and goats worldwide, may also infect deer. The aim of this study was to evaluate whether South American deer are infected with M. ovis. EDTA-anticoagulated blood samples from a herd of 32 captive South American deer were collected. DNA extraction of blood samples was performed followed by PCR amplification of the 16S and 23S rRNA genes, and sequencing of products. Using M. ovis PCR, 27/31 (87%) were positive, including 21/22 Mazama nana; 2/3 Mazama americana and 4/6 Blastocerus dichotomus. Sequencing of the nearly entire 16S rRNA gene of 26/27 positive samples showed 98.2-98.8% identity to M. ovis of sheep (GenBank, AF338268) and 98.6-99.4% identity to M. ovis-like of a fawn (FJ824847); the 23S rRNA gene from one of these isolates and the fawn's had 97.6% identity. The remaining isolate had just 94.9% identity to the 16S rRNA gene of M. ovis and only 89.4% identity to the 23S rRNA gene of the fawn's M. ovis. This is the first report of M. ovis in captive South American deer, revealing a high prevalence of hemoplasma infection in these animals. 相似文献
113.
Gizele Odete de Sousa Ismael de Jesus Matos Vigas Jessivaldo Rodrigues Galvo Susana Silva Conceio Tiago Kesajiro Moraes Yakuwa Mauro Junior Borges Pacheco Thiago Costa Viana 《植物养料与土壤学杂志》2021,184(1):76-87
Background : The açaí palm (Euterpe oleracea Mart.) is a species native to the Amazon region, where the largest stock of these palms is located in the state of Pará, Brazil. This species occurs predominantly spontaneously in the plateau and plains areas of the Amazonian estuary. Water deficit is the main limiting factor of plants, negatively regulating the growth, metabolism and productivity of crops. Aim : This study aimed to deepen the ecophysiological and biochemical responses of Euterpe oleracea Mart. to a water deficiency condition in agroforestry systems. Methods : The study was carried out in a defined period of lowest rainfall in the region, which runs from July to October, averaging 58.6 mm for those months, such as location, age, uniformity, health, development, height and diameter of the stipe, in order to determine the biochemical variables. Responses to biochemical components under water deficit such as starch, sucrose and carbohydrates increased for rachis and fruits. Results : The concentrations of ammonia and proteins increased in stems and fruits. For amino acids, the structures that accumulated these organic compounds were fruits and arrow. One of the most representative amino acids against water deficiency is proline, and its increase in plant tissues is due to osmoprotein function, especially for structures such as rachis, fruit and petioles + rachis. Conclusions : Therefore, Euterpe oleracea Mart. presents excellent physiological plasticity to deal with stressful conditions as well as adaptive behavior to overcome this deficiency. 相似文献
114.
Bruna T. Canizella Juliana A. Sousa Larissa A. C. Moraes 《Journal of plant nutrition》2013,36(17):2189-2199
AbstractIn the last decades, soybean (Glycine max (L.) Merrill) was the crop with the highest acreage in Brazil. Soybean has been cropped under unfertile soils as sandy soils and those under pasture decaying where applying high fertilizer levels have significant responses. The presence of calcium (Ca) and magnesium (Mg) concentration in the upper layers promotes ions imbalanced concentration in soil solution because the soil acidity correction reduces the uptake of other cations as zinc (Zn). The objective of this study was to evaluate under nutritive solution conditions, the Mg influence in Zn distribution and mobilization into plants from four soybean cultivars with different nutritional requirements. The experimental design was complete randomized blocks in factorial scheme 4?×?2?×?4 being with four soybean cultivars (FT Estrela, DM Nobre, IAC 17, and IAC 15-1), two Mg rates (0.1 and 1.0?mmol?L?1), four Zn rates (0, 1, 2, and 5?µmol?L?1), and four replicates. The IAC 17 and FT Estrela cultivars with determinate growth and high nutritional requirements, and the IAC 15-1 and DM Nobre with tolerance to soils partially corrected, average fertility, or both were investigated. In the highest Mg rates, we verified increase in grain yield (GY) as well as in the Zn rates up to 2.0?µmol?L?1. The Mg?×?Zn interaction was significant and the IAC 17 cultivar was the most responsive to Zn under nutritive solution. The foliar nutrient concentration was significantly modified by Mg rates. The Mg at 1.0?mmol?L?1 presented the lowest nutrient concentration in soybean plants and increased the shoot dry weight yield (SDWY) in plant and grain no matter the nutritional requirement from every cultivar. 相似文献
115.
Phosphorus (P) deficiency is one of the most yield limiting factors in crop production in Brazilian Oxisols. A greenhouse experiment was conducted to evaluate 20 upland rice genotypes at low (25 mg P kg?1) and high (200 mg P kg?1) P levels applied to a Brazilian Oxisol. Grain yield and yield components were significantly influenced by P level and genotype treatments. There was a significant interaction between P level and genotype treatments in relation to grain yield, indicating genotypes responded differently under two P levels. Based on grain yield efficiency index (GYEI), genotypes were classified into efficient, moderately efficient and inefficient groups. The efficient genotypes in utilizing P were ‘BRA052053’, ‘BRS Primavera’, ‘BRA052015’, ‘BRA052023’, ‘BRA01506’, ‘BRA052045’, ‘BRA032033’, ‘BRA01596’ and ‘BRA052034’. Remaining genotypes were classified as moderately efficient in P use efficiency. None of the genotypes were fall into inefficient group. Grain yield was significantly and positively related with shoot dry weight, panicle number, grain harvest index, 1000-grain weight and had a negative and significant correlation with spikelet sterility. Grain weight was having maximum contribution in total rice plant weight comparing to root and shoot, indicating improvement in harvest index of modern Brazilian upland rice cultivars by breeding. 相似文献
116.
Alex Humberto Calori Thiago Leandro Factor José Carlos Feltran Eduardo Yuji Watanabe Carolina Cinto de Moraes Luis Felipe Villani Purquerio 《Journal of plant nutrition》2013,36(17):2200-2209
AbstractMost seed potatoes in Brazil are produced in beds, pots or boxes containing substrate, but the yields are low. Aeroponic systems are one strategy for increasing the yield. However, the concentration of nutrient solutions, managed by varying the electrical conductivity (EC), is of upmost importance and can alter plant responses. Plant density is another important factor for obtaining high yields. The objective of this study was thus to determine the effect of nutrient-solution EC and plant density on plant and seed potato production in aeroponic system. The experimental design was a randomized block with a split-plot design and four replicates, with plots for EC and subplots for plant density. Two potato cultivars were tested. The best ECs for “Agata” and “Asterix” were 2.1 and 1.7?dS?m?1, respectively. The highest plant density (100 plants m?2) for both cultivars produced the highest minituber yield and economic feasibility. 相似文献
117.
Roberta B. Ferreira Jair C. Moraes Alexander M. Auad Marcy G. Fonseca 《Journal of pest science》2013,86(2):161-166
This study evaluated the impact of different CO2 levels on the biological characteristics of Mahanarva spectabilis (Distant) and on the performance of forage grasses. The signal grasses Brachiaria decumbens Stapf (susceptible) and Brachiaria brizantha (A. Rich.) (resistant), the elephant grass Pennisetum purpureum (Schum.), including the Roxo de Botucatu cultivar (susceptible) and the Pioneiro cultivar (resistant) and the insects were kept in climate-controlled chambers with constant low (250 ppm) CO2 levels, constant high (500 ppm) CO2 levels, or fluctuating CO2 levels (mean, 368 ppm). Among these three CO2 treatments, no significant differences were found in the nymphal survival of M. spectabilis when the nymphs were fed on two signal grass species. On the other hand, under a constant low CO2 level (250 ppm), nymphal survival rates were significantly lower when the insects were kept in Roxo de Botucatu and Pioneiro cultivars. The mean adult longevity values for M. spectabilis were not significantly different among the three levels of CO2 evaluated. We observed that increased CO2 levels improved the performance of M. spectabilis and elephant grass cultivars in accumulating dry mass, which was not evident in signal grass. We further conclude that the levels of susceptibility and resistance of the forages tested will be maintained in future scenarios under which atmospheric CO2 levels are expected to increase. 相似文献
118.
Renata Squarzoni Eduardo Perlmann Andrea Antunes Liliane Milanelo Paulo Srgio De Moraes Barros 《Veterinary ophthalmology》2010,13(Z1):86-90
Objective To report the biometric values and ultrasonographic aspects of the normal eye of the Striped owl (Rhinoptynx clamator). Sample population Twenty‐seven healthy, free‐living, adult Striped owls from the Ecological Park of Tiete Veterinary Ambulatory (Sao Paulo, Brazil). Procedures Both eyes of all owls underwent B‐mode ultrasonographic examination and biometry was performed for lens axial length (WL), depth of the anterior (AC) and vitreous (VC) chambers, axial length of the globe (LB) and the pecten oculi (LP) of both eyes, using a 12 MHz probe. The owls were manually restrained without sedation and the eyes were topically anesthetized. Results Biometric and statistical findings were as follows: in the left eye, the means and standard deviations were: LB = 23.76 ± 0.92 mm, WL = 7.79 ± 0.27 mm, AC = 4.27 ± 0.47 mm, VC = 11.36 ± 0.29 mm and LP = 5.69 ± 0.50 mm; in the right eye, the values were: LB = 24.25 ± 0.79 mm, WL = 8.03 ± 0.40 mm, AC = 4.56 ± 0.52 mm, VC = 11.40 ± 0.25 mm, and LP = 5.68 ± 0.41 mm. No significant differences were found between left and right eyes measurements of LB, WL, AC, VC, and LP dimensions. Conclusions Ocular ultrasound aspects and biometric values of the Striped owl are reported. The study’s results provide means for various ocular measurements. The ultrasound is an easy and safe exam to be performed in the Striped owl’s eyes. 相似文献
119.
Dietary carbohydrate and food processing affect the digestive physiology of Piaractus mesopotamicus 下载免费PDF全文
C.A. Honorato L.C. de Almeida R.Y. Camilo G. Moraes C.D.S. Nunes D.J. Carneiro 《Aquaculture Nutrition》2016,22(4):857-864
The responses of the digestive physiology of juvenile pacu to different diet processing were studied. Fish were fed with isoproteic diets with 260 g kg?1 of crude protein (CP) containing different levels of carbohydrate (DCh) (400 or 500 g kg?1), and two diet processing (pelletization or extrusion) for 90 days. Fish fed with extruded diets showed decrease of the gastrointestinal transit time (GI transfer) and of the amylase activity, but maltase activity did not alter. Protease activity of intestine depicted increase when the DCh was raised. The increase of DCh also caused enhancement of the apparent digestibility coefficient of CP (ADCCP) in fish fed with extruded diets. Fish fed with pelletized diets showed increase of the amylase activity in pyloric caecum independently of the dietary carbohydrate level. No interaction was observed between dietary carbohydrate level and diet processing. Maltase activities from the stomach and intestine of pacu were not responsive to the carbohydrate level. The extrusion process improved the carbohydrate availability and the digestion efficiency of protein in pacu. Digestive enzymes of pacu were modulated either by nutrients or diet processing. 相似文献
120.
Structural features of lignin obtained at different alkaline oxidation conditions from sugarcane bagasse 总被引:1,自引:0,他引:1
Priscila Maziero Mario de Oliveira Neto Douglas MachadoTatiana Batista Carla Cristina Schmitt CavalheiroMiguel G. Neumann Aldo Felix CraievichGeorge Jackson de Moraes Rocha Igor Polikarpov Adilson Roberto Gonçalves 《Industrial Crops and Products》2012,35(1):61-69
Lignin is a macromolecule frequently obtained as residue during technological processing of biomass. Modifications in chemical structure of lignin generate valuable products, some with particular and unique characteristics. One of the available methods for modification of industrial lignin is oxidation by hydrogen peroxide. In this work, we conducted systematic studies of the oxidation process that were carried out at various pHs and oxidizing agent concentrations. Biophysical, biochemical, structural properties of the oxidized lignin were analyzed by UV spectrophotometry, Fourier transform infrared spectroscopy, scanning electron microscopy and small angle X-ray scattering. Our results reveal that lignin oxidized with 9.1% H2O2 (m/v) at pH 13.3 has the highest fragmentation, oxidation degree and stability. Although this processing condition might be considered quite severe, we have concluded that the stability of the obtained oxidized lignin was greatly increased. Therefore, the identified processing conditions of oxidation may be of practical interest for industrial applications. 相似文献