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41.
Tamara Martin‐Gimnez Antonio M. Cruz Agustín Barragn Estefanía Montero Pedro G. Sanchez Guillermo Caballero Ignacio Corradini 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2019,33(6):2780-2785
Occipital condylar fractures (OCFs) causing delayed onset lower cranial nerve paralysis (LCNPs) are rare. We present a 7‐year‐old Friesian horse with delayed onset dysphagia caused by vagus nerve (CNX) paralysis and suspicion of glossopharyngeal nerve (CNIX) paralysis developed several days after a minor head injury. Endoscopic examination revealed right laryngeal hemiplegia and intermittent dorsal displacement of the soft palate. An area of submucosal hemorrhage and bulging was appreciated over the dorsal aspect of the medial compartment of the right guttural pouch. Radiological examination of the proximal cervical region showed rotation of the atlas and the presence of a large bone fragment dorsal to the guttural pouches. Occipital condyle fracture with delayed onset cranial nerve paralysis was diagnosed. Delayed onset cranial nerve paralysis causing dysphagia might be a distinguishable sign of OCF in horses. Delayed onset dysphagia after head injury should prompt equine clinicians to evaluate the condition of the atlanto‐occipital articulation and skull base. 相似文献
42.
Mercedes Alvarez Luis Anel‐Lopez Juan Carlos Boixo Cesar Chamorro Marta Neila‐Montero Rafael Montes‐Garrido Paulino de Paz Luis Anel 《Reproduction in domestic animals》2019,54(Z4):32-40
Ovine artificial insemination (OAI) is not commonly performed because of specific problems related to semen application techniques, leading to highly variable results. The ideal methodology (frozen‐thawed semen/vaginal route) is unfeasible under field conditions due to the cervix morphology of the ewe, which prevents the process of intrauterine insemination necessary to obtain acceptable results. Currently, OAI commercial programmes use superficial cervical insemination, CAI (vaginal), with chilled semen (15°C) and intrauterine insemination, LAI (laparoscopic), with frozen‐thawed semen. The ability to improve upon these contrasting techniques may be derived from examining certain poorly studied factors such as insemination time, productive state of females and alternatives of seminal preservation, some of which we reviewed in this work. This interim solution will remain in use until AI by the vaginal route with frozen‐thawed semen is developed, but it poses new challenges in optimizing the freezing of the sperm and adapting the cervical (CAI) and/or transcervical intrauterine AI (TCAI). In this review, we address the current problems and evaluate their methodological (mechanical) and chemical (dilation) alternatives. Currently, TCAI is a methodologically complex technique with poor fertility results, so further studies are needed to improve the logistics of this procedure and the results of its application. 相似文献
43.
S. V. K. Jagadish E. M. Septiningsih A. Kohli M. J. Thomson C. Ye E. Redoña A. Kumar G. B. Gregorio R. Wassmann A. M. Ismail R. K. Singh 《Journal of Agronomy and Crop Science》2012,198(5):360-373
Rice, with its wide geographic distribution extending from 50°N to 35°S, is expected to be the most vulnerable cultivated crop to future changing climates. Among the different abiotic stresses, extreme temperatures coinciding with critical developmental stages, increasingly frequent floods and drought spells, and worsening sea water inundation are some of the major threats to sustainable rice productivity. Following the successful implementation of molecular marker‐assisted backcrossing to introgress large‐effect QTL for submergence tolerance in rice mega varieties, rice breeding for drought, salinity and, recently, heat tolerance is employing the same approach. Although tolerance for combined submergence and salinity has been achieved, developing rice varieties with multiple tolerance for other abiotic and biotic stresses and finding the appropriate agronomic package to exploit their performance remain a challenge. The major bottleneck is the lack of unidentified large‐effect QTL for other abiotic stresses that are strongly influenced by genotype × environment (G × E) interaction. Rapid advances in the use of molecular tools, including a plethora of SNP markers, are expected to facilitate the development of major abiotic stress‐tolerant rice. In response to the actual farmer field situation, progress achieved in understanding and developing independent abiotic stress tolerance is being exploited to combine tolerances (for example, heat and drought; salinity and submergence) to address emerging environmental problems across a wide range of rice ecosystems. 相似文献
44.
G. Moreno Marcos J. J. Obrador E. García E. Cubera M. J. Montero F. Pulido C. Dupraz 《Agroforestry Systems》2007,70(1):25-40
Dehesas are extant multi-purpose agroforestry systems that consist of a mosaic of widely-spaced scattered oaks (Quercus ilex L.) combined with crops, pasture or shrubs. We aimed to clarify the role of trees in dehesas of CW Spain focussed on the
analysis of tree-understorey interactions. Spatial variability of resources (light, soil moisture and fertility), microclimate,
fine roots of both herbaceous plants and trees and forage yield was measured. Additionally, we compared the nutritional and
physiological status, growth and acorn production of oaks in cropped (fodder crop), grazed (native grasses) and encroached
(woody understorey) dehesa plots. Significant light interception by trees was limited to the close vicinity of the trees,
with very low reduction away from them. Both microclimate and soil fertility improved significantly in the trees vicinity,
irrespective of soil management. Soil moisture varied very few with distance from the trees, as a result of the extended root
system of oaks. Root systems of trees and herbs did not overlap to a great extent. Crop production was higher beneath trees
than beyond the trees in unfertilised plots and foliar nutrient content of oaks did not increase significantly with crop fertilisation,
indicating that trees and crops hardly compete for nutrients. Moreover, trees benefited from the crop or pasture management:
trees featured a significantly improved nutritional and physiological status, a faster growth and a higher fruit productivity
than trees growing in encroached or forest plots. 相似文献
45.
Mariola Sánchez-González Rafael Calama Isabel Cañellas Gregorio Montero 《Annals of Forest Science》2007,64(3):301-312
In this study, we evaluate the influence of different variables on cork thickness in cork oak forests. For this purpose, first we fitted a multilevel linear mixed model for predicting average cork thickness, and then identified the explanatory covariates by studying their possible correlation with random effects. The model for predicting average cork thickness is described as a stochastic process, where a fixed, deterministic model, explains the mean value, while unexplained residual variability is described and modelled by including random parameters acting at plot, tree, plot × cork harvest and residual within-tree levels, considering the spatial covariance structure between trees within the same plot. Calibration is carried out by using the best linear unbiased predictor (BLUP) theory. Different alternatives were tested to determine the optimum subsample size which was found to be appropriate at four trees. Finally, the model was applied and its performance in the estimation of cork production was tested and compared with the cork weight model traditionally used in Spain. 相似文献
46.
Natural regeneration of stone pine (Pinus pinea L.) stands in the Central Range of Spain can be difficult to attain. The success of this regeneration is affected by factors
such as the total amount of seed available, the short dispersal ability of the pinyon, the conditions required for germination,
specific problems associated with the establishment, early survival of the seedlings due to severe summer heat and drought,
competition for water and mineral resources and grazing damage. This study focuses on seed availability. The amount of available
seeds depends on the number and size of the cones and the number of viable pinyons within the cones. In stone pine stands,
both variables show great year to year variability. Both cone and seed production, for a given year, are also conditioned
by the vigour and health of the tree, its size, the condition and attributes of the stand and the loss of seed through pests
or predation. In this study, the main factors which influence cone and pinyon production are identified and a multivariate
model to predict annual cone and viable seed production is developed. To consider the correlation among observations coming
from the same tree, stand or year, random components are included in the model. The multivariate random structure allows for
future calibration of the model for a given year from a small additional sample of observations. It is important to know the
total amount of viable seed produced in a stand for a given year since regeneration cuttings for Stone pine should be concentrated
in high crop years. 相似文献
47.
González LM Villalobos N Montero E Morales J Sanz RA Muro A Harrison LJ Parkhouse RM Gárate T 《Veterinary parasitology》2006,142(1-2):95-101
In the present work, the species-specific identification of Taeniid spp. cysticerci and sarcocystis cysts isolated from infected pigs and cattle was achieved by PCR. In particular: (i) multiplex-PCR derived from HDP2 DNA fragment, specific for Taenia saginata/Taenia solium; (ii) PCRs and PCR-RFLPs of the rDNA internal transcribed spacers 1 and 2 (ITS1 and ITS2) for the differential diagnosis of taeniids; (iii) PCR derived from the 18S rRNA gene and sequencing, specific for Sarcoystis spp. The combined application of these three PCR protocols provided an unequivocally specific diagnosis of T. saginata, T. solium, T. hydatigena, Sarcocystis hominis and Sarcocystis suihominis, and may have practical application in the identification of calcified degenerating or morphologically dubious cysts, for example in the slaughter house situation or in human biopsy samples. 相似文献
48.
Gregorio Iraola Martín Hernández Lucía Calleros Fernando Paolicchi Silvia Silveyra Alejandra Velilla Luis Carretto Eliana Rodríguez Ruben Pérez 《Journal of veterinary science (Suw?n-si, Korea)》2012,13(4):371-376
Campylobacter (C.) fetus (epsilonproteobacteria) is an important veterinary pathogen. This species is currently divided into C. fetus subspecies (subsp.) fetus (Cff) and C. fetus subsp. venerealis (Cfv). Cfv is the causative agent of bovine genital Campylobacteriosis, an infectious disease that leads to severe reproductive problems in cattle worldwide. Cff is a more general pathogen that causes reproductive problems mainly in sheep although cattle can also be affected. Here we describe a multiplex PCR method to detect C. fetus and differentiate between subspecies in a single step. The assay was standardized using cultured strains and successfully used to analyze the abomasal liquid of aborted bovine fetuses without any pre-enrichment step. Results of our assay were completely consistent with those of traditional bacteriological diagnostic methods. Furthermore, the multiplex PCR technique we developed may be easily adopted by any molecular diagnostic laboratory as a complementary tool for detecting C. fetus subspecies and obtaining epidemiological information about abortion events in cattle. 相似文献
49.
Aranzazu Hernández-Andrés Miriam Pérez-Mateos Pilar Montero Maria Del Carmen Gómez-Guillén 《Fisheries Science》2008,74(4):899-910
ABSTRACT: High-pressure technology is used as an alternative to heat processing because of its inactivating effect on microorganisms and enzymes. However, it can also alter the structure of other muscle proteins. The present study compares the effects of high pressure (300 MPa, 7°C, 20 min) on the proteolytic degradation and alterations in the myofibrillar proteins of sardine and blue whiting muscle. Also, muscle homogenates and enzyme extracts were pressurized in order to evaluate the high-pressure effects on unprotected proteolytic enzymes outside the whole muscle structure. Peak proteolytic activity was found to occur at 55°C in both species. The peak activity pH was pH 3 for the sardine and pH 8 for the blue whiting; the main enzyme families being aspartic proteases in the former and alkaline serine proteases in the latter. Pressurization lowered activity levels at the peak activity pH and temperature in the fish muscle (by 30.8% in the sardine and by 9.5% in the blue whiting) and also slightly in the enzyme extracts (by 16.8% in the sardine and by 19.4% in the blue whiting). The electrophoretic profiles disclosed higher protein degradation in the pressurized muscle. Overall, the observed changes in proteolytic activity can be attributed not only to the effect of high pressure on the enzymes, but also and mainly, to the effect on other muscle proteins. 相似文献
50.
Rice (Oryza sativa L.) is the most important economic activity on earth as it is second largest single use of the land for food production and also consumed by the half of the world's population. Salinity is the one of the most common abiotic problem in rice growing areas of the world. Millions of hectares in the tropics, arid and semi arid region could be potential rice growing areas but either left idle or cropped with very low yielding varieties due to the lack of suitable salt tolerant high yielding modem varieties. 相似文献