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Landscape Ecology - Species-area relationship models are useful in conservation planning; however these models could be strengthened with the addition of a latitudinal factor. We built... 相似文献
204.
Preliminary assessment of in vivo safety of potentially probiotic lactic acid bacteria for American bullfrog culture
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Sergio E Pasteris Gabriela Montel Mendoza Ricardo J Llanos Franco J Pucci Alcaide María E F Nader‐Macías 《Aquaculture Research》2017,48(5):2157-2172
The effect of the administration of beneficial lactic acid bacteria (LAB): Lactococcus lactis CRL 1584, L. lactis CRL 1827, Enterococcus gallinarum CRL 1826 and combined CRL 1584+ CRL 1826 on the development of bullfrog embryos from the hatching stage until 31 days (tadpole) was evaluated. In vitro assays indicated that 103, 106 and 109 CFU mL?1 single LAB strains remained viable until 24 h in 10% Ringer. Around 109 CFU mL?1 LAB (individually and combined) were used in an experimental design built to evaluate their effect when administrated at different intervals (three 7‐day cycles with 5‐day rest periods in between) to embryos until day 31. The highest potentially beneficial population (LAB) numbers were detected in the LAB‐treated groups. All the LAB‐treatments increased it and were significantly higher than the controls. Although the highest, potentially pathogenic, population (Red‐Leg Syndrome‐RLS‐related pathogens) numbers were detected in the control and the lowest in the CRL 1584+ CRL 1826‐treated group, they did not differ significantly. Stereoscopic studies showed no malformations in any LAB‐treated group and all the specimens reached the same stage of their biological cycle with a survival >94%. The histological structure of target organs for RLS‐associated pathogens (intestine and skin) and stomach was not affected and the spleen was developed. Only the LAB‐treated groups showed microorganisms associated with the intestinal mucus, without inflammatory reaction in the lamina propria. This is the first report on the evaluation of the absence of adverse effects after LAB administration to bullfrog embryos using indigenous microorganisms. 相似文献
205.
The presence or absence of motorized boats, partnerships and multispecies catches characterize the fisheries of São Francisco River, Minas Gerais, Brazil. Fishing activity based on 109 interviews, carried out in the wet (high water: February and March) and dry (low water: July and August) seasons, with professional fishermen are described. Aiming to identify the fishery income components, a covariance model was proposed, with the income as the response variable, related to the factors: fishing ground; use of motorized or paddle boat; seasonality; presence of fishing assistant; and the following covariates: capture in weight in the week prior to the interview; fisherman experience in yrs; and distance (km) travelled for fishing. The results indicated that the main contributions to income were the absence of an engine (because of high price of the fuel), the absence of a partner (because of low capture) and the amount of fish caught by the fishermen. 相似文献
206.
Tommaso Chiti Lorenzo Gardin Lucia Perugini Roberta Quaratino Francesco Primo Vaccari Franco Miglietta Riccardo Valentini 《Biology and Fertility of Soils》2012,48(1):9-17
The aim of this work was to quantify the soil organic C (SOC) stock in the top 30 cm of mineral soil for the whole Italian
territory, according to the different land use types of the Intergovernmental Panel on Climate Change (IPCC) cropland category
(arable land, agroforestry, vineyards, olive groves, orchards and rice fields), as a basis for future land use scenarios and
to address mitigation policy at country level. A database for SOC stock was created with the data from the national project
denominated SIAS and partly from regional map reports. All data were referred to the year 2000 since they were derived from
surveys conducted from 1995 to 2005. The data were stratified according to the Italian climatic regions, the landscape position
and the IPCC cropland subcategories. Taking into account the uncertainty in the estimate, the mean SOC stock values of the
different subcategories show significant differences (p < 0.05) among climatic regions and landscapes, ranging from 41.9 ± 15.9 Mg C ha−1 in the vineyards to 63.3 ± 27.9 Mg C ha−1 in the rice fields. Generally, a small decrease of the SOC stock from the temperate regions toward the Mediterranean ones
is observed. Taking into account the mean value of each subcategory and the country area they occupied in 2000, the total
C stored in the upper 30 cm of soil was estimated at 490.0 ± 121.7 Tg C. The resulting estimate represents the 17% of the
value reported by another study for the soil of the whole country down to 50 cm depth, suggesting the importance of preserving
this large C pool. Considering the cropland category as a whole, the estimated mean SOC stock is 52.1 ± 17.4 Mg C ha−1, similar to that reported for other European countries, 50–60 Mg C ha−1. In conclusion, the assessment of the mean SOC stock of the different cropland land uses, landscape position and climate
regions could notably help when assessing the impact of different agricultural practices and future stock change evaluation. 相似文献
207.
Lolo M Pedreira S Fente C Vázquez BI Franco CM Cepeda A 《Journal of agricultural and food chemistry》2005,53(8):2849-2852
A study of the depletion of enrofloxacin residues in eggs was carried out using a diphasic dialysis procedure for the extraction of fluoroquinolone residues from the matrix. Enrofloxacin was administered to laying hens through the intramuscular route (15 mg/day) and orally (12 mg/day). After daily collection, the egg albumen and the egg yolk were separated, and the residue levels were determined using an HPLC-MS (API-ESI) method. The enrofloxacin and ciprofloxacin peaks gradually increased until the fifth day, because the drug was employed for 5 days. However, differences were observed in the depletion curves of enrofloxacin and its metabolite when both parts of the egg and the mode of administration were considered. 相似文献
208.
Marta Vascellari Silvia Tasca Tommaso Furlanello Erika Carli Carlo Patron Franco Mutinelli Marco Caldin 《Journal of veterinary diagnostic investigation》2007,19(2):205-208
An unusual clinical presentation of lymphoma with vertebral involvement in a dog is reported. A 20-month-old intact female Golden Retriever presented with progressive paraparesis and anorexia. Complete blood count and serum biochemistry profile demonstrated pancytopenia and hypercalcemia. Ventral fusion of the lumbar vertebrae by new bony tissue deposition was evident on X-ray and CT scan. Fine needle aspiration revealed neoplastic lymphoid cells in lymph nodes and bone marrow. Histologically, vertebral bone and osteophytes, liver, bone marrow, kidney, and lymph nodes were diffusely infiltrated by neoplastic, lymphoid cells, with scant cytoplasm and round hyperchromatic nuclei. Polyostotic and medullary T-cell lymphoma with spondylosis was diagnosed. Lymphoma mainly affecting bone is uncommon in the dog. The present case differs from previously described polyostotic lymphomas in clinical signs of the disease, mainly attributable to spondylarthrosis. In addition, lymphomatous proliferation was associated with osteoproductive lesions of the vertebrae. 相似文献
209.
Eduardo A. Guarnera MD Elisa M. Zanzottera MVD Hector Pereyra MD Anibal J. Franco MVD 《Veterinary radiology & ultrasound》2001,42(4):352-354
The sanitary and economic impact of cystic echinococcosis is serious in those countries where it becomes endemic. Ultrasonography is one technique that may be used to diagnose this disease in endemic areas. In parasitized sheep, hydatid cysts appear sonographically as a round hypoechoic structure. Twenty two sheep destined for slaughter were studied sonographically and imaging findings compared to post-mortem findings. Three sheep with hydatid cysts were identified. Eighty additional sheep not destined for slaughter were also studied. Echinococcus granulosus cysts were detected in three animals. Forty sheep from a non-endemic area had no hepatic cysts. The in vivo sonographic study of sheep provides a useful screening tool for echinococcosis. 相似文献
210.
Stefan M Keller Barbara C Keller Paula Grest Claas T B?rger Franco Guscetti 《Journal of veterinary diagnostic investigation》2007,19(6):652-659
In most validation studies of tissue microarrays (TMAs), a fixed number of cores with a given diameter are analyzed to determine the degree of accuracy by which the TMA represents the whole section. The statistical model described in the present study predicts this property for various combinations of 2 core sizes (0.6 mm and 1.2 mm) and different core numbers. The model was based on artificial TMA core biopsies generated from Ki-67 and active caspase-3 immunostains of 40 canine lymphoma samples. Positivity was scored on a continuous scale, and a large number of cells were analyzed with the help of semiautomated cell counting. Despite considerable differences in range and distribution of Ki-67 and active caspase-3 positivity values, the model predictions showed a high degree of agreement for both markers. Comparison of 0.6 mm and 1.2 mm cores indicated that the use of small cores necessitates inclusion of a larger number of samples but requires counting a markedly smaller number of cells. Suitability of TMAs to determine the immunophenotype of the whole section was assessed using 2 different combinations of core sizes and numbers. Both displayed a high degree of concordance with the whole section (kappa(0.6) = 0.79; kappa(1.2) = 0.91). The present study provides a basis for the use of TMAs in future high-throughput immunohistochemical investigations of selected markers in canine lymphomas. The statistical model presented can be used to determine an optimal TMA design depending on a desired accuracy. 相似文献