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101.
Luciane Tourem Gressler Ana Paula Konzen Riffel Thaylise Vey Parodi Etiane Medianeira Hundertmarck Saccol Gessi Koakoski Sílvio Teixeira da Costa Maria Amália Pavanato Berta Maria Heinzmann Bráulio Caron Denise Schmidt Susana Francisca Llesuy Leonardo José Gil Barcellos Bernardo Baldisserotto 《Aquaculture Research》2014,45(6):1061-1072
Responses to anaesthesia with essential oil (EO) of Aloysia triphylla (135 and 180 mg L?1) and tricaine methanesulfonate (MS222) (150 and 300 mg L?1) were assessed in silver catfish. Exposure to the anaesthetics elicited a stress response in the species. In the case of MS222, it was displayed as a release of cortisol into bloodstream, elevation in hematocrit and plasma ion loss. The EO presented cortisol‐blocking properties, but increased haematocrit and disturbances of hydromineral balance were observed. Liver antioxidant/oxidant status of EO and MS222‐anaesthetized silver catfish was also estimated. The synthetic anaesthetic induced lipoperoxidation, notwithstanding increased catalase contents, whereas the naturally occurring product was capable of preventing the formation of lipid peroxides, possibly due to combined actions of catalase and glutathione‐S‐transferase. Anaesthetic efficacy was also tested via induction and recovery times. Overall, the promising results obtained for the physiological parameters of the EO‐treated fish counterbalanced the slight prolonged induction time observed for 180 mg L?1. As for 135 mg L?1, both induction and recovery times were lengthy; despite that, the EO was able to promote oxidative protection and mitigate stress. None of the MS222 concentrations prompted such responses concomitantly. 相似文献
102.
A Mediterranean japonica rice (Oryza sativa) cultivar improvement through anther culture 总被引:1,自引:0,他引:1
X. Serrat M. Cardona J. Gil A. M. Brito L. Moysset S. Nogués E. Lalanne 《Euphytica》2014,195(1):31-44
Certified seed producers systematically select and propagate registered varieties year after year in order to maintain their uniformity and the original registered cultivar traits. However, natural mutations, spontaneous breeding between varieties and alien grain contamination can introduce undesirable variability. NRVC 980385 is a temperate japonica rice cultivar (Oryza sativa ssp. japonica) first registered in Spain in 2002. In 2005 certification tests detected a plot differing from the original traits in terms of uniformity and height suggesting the presence of a certain heterozygosis. This material was therefore seen as an opportunity to obtain newly stabilized doubled haploid (DH) lines which could compete in the Spanish short grain seed market. In this study, an in vitro anther culture protocol is defined which also covers the field tests selection to obtain four new, improved and stabilized DH derived lines ready to be registered for commercial proposes. This took just 4 years from the initial anther collection until new lines were grown in large scale field trials. Consequently, this protocol reduces the time for obtaining field assessed DH lines thereby having considerable advantages over other techniques by both maintaining the original registered cultivars and/or generating new derived varieties. 相似文献
103.
104.
Rivero MA Vázquez JM Gil F Ramírez JA Vilar JM De Miguel A Arencibia A 《Anatomia, histologia, embryologia》2009,38(1):18-22
The aim of this study was to provide a detailed anatomic atlas of the cranial abdomen by means of computed tomography (CT). Three mature dogs, all mixed breed males, were used. The dogs were sedated, anaesthetized and positioned in sternal recumbency. CT scans from the eighth thoracic vertebra to the fourth lumbar vertebra were performed using a third-generation equipment (TOSHIBA 600HQ scanner) with 1 cm slice thickness. CT-images of the cranial abdomen were taken with soft-tissue window (WL: −14, WW: 658) settings. Dogs were killed and vascular-injection technique was performed: red and blue latex filled the vascular system. Injected dogs were frozen in the same position as used for CT examination and sectioned with an electric bandsaw at 1-cm-thick intervals. The cuts matched as closely as possible to the CT-images. The anatomic sections were compared and studied with the corresponding CT-images, and clinically relevant abdominal anatomic structures were identified and labelled on the corresponding CT-images. The results of our study could be used as a reference for evaluating CT-images of the canine cranial abdomen with abdominal diseases. 相似文献
105.
N. Panella-Riera A. Velarde A. Dalmau E. Fbrega M. Font i Furnols M. Gispert J. Soler J. Tibau M.A. Oliver M. Gil 《Livestock Science》2009,124(1-3):277-287
Sixty-nine entire male pigs with different halothane genotype (homozygous halothane positive — nn-, n = 36; and homozygous halothane negative — NN-, n = 33) were fed with a supplementation of magnesium sulphate (Mg) and/or l-tryptophan (Trp) in the diet for 5 days before slaughter. Animals were housed individually and were submitted to stressful ante mortem conditions (mixed in the lorry according to treatments and transported 1 h on rough roads). Individual feed intake was recorded during the 5-d treatment. At the abattoir, pig behaviour was assessed in the raceway to the stunning system and during the stunning period by exposure to CO2. Muscle pH, colour, water holding capacity, texture and cathepsin activities were determined to assess meat quality. The number of pigs with an individual feed intake lower than 2 kg/day was significantly different among diets (P < 0.05; Control: 8.7%; Mg&Trp: 43.5%; Trp: 17.4%) and they were considered to have inadequate supplement intake. During the ante mortem period, 15.2% of pigs included in the experiment died, and this percentage decreased to 8.7% in those pigs with a feed intake > 2 kg/day, all of them from the stress-sensitive pigs (nn). In general, no differences were observed in the behaviour of pigs along the corridor leading to the stunning system and inside the CO2 stunning system. During the stunning procedure, Trp diet showed shorter periods of muscular excitation than control and Mg&Trp diets. The combination of a stressful ante mortem treatment and Mg&Trp supplementation led to carcasses with high incidence of severe skin lesions. Different meat quality results were found when considering all pigs or considering only those with adequate supplement intake. In this later case, Trp increased pH45 (6.15) vs Control diet (5.96) in the Longissimus thoracis (LT) muscle (P < 0.05) and pH at 24 h (Trp: 5.59 vs C: 5.47) led to a higher incidence of dark, firm and exudative (DFD) traits in SM muscle (P < 0.05). Genotype affected negatively all the meat quality traits. Seventy-five percent of LT and 60.0% of the SM muscles from nn pigs were classified as pale, soft and exudative (PSE), while none of the NN pigs showed these traits (P < 0.0001). No significant differences were found between genotypes on the incidence of DFD meat.Due to the negative effects observed in the Mg&Trp group in feed intake and carcass quality, the utilization of a mixture of magnesium sulphate and tryptophan is not recommended. 相似文献
106.
Feasibility of near infrared spectroscopy for analyzing corn kernel damage and viability of soybean and corn kernels 总被引:1,自引:0,他引:1
Lidia Esteve Agelet David D. Ellis Susan Duvick A. Susana Goggi Charles R. Hurburgh Candice A. Gardner 《Journal of Cereal Science》2012
The current US corn grading system accounts for the portion of damaged kernels, measured by time-consuming and inaccurate visual inspection. Near infrared spectroscopy (NIRS), a non-destructive and fast analytical method, was tested as a tool for discriminating corn kernels with heat and frost damage. Four classification algorithms were utilized: Partial least squares discriminant analysis (PLS-DA), soft independent modeling of class analogy (SIMCA), k-nearest neighbors (K-NN), and least-squares support vector machines (LS-SVM). The feasibility of NIRS for discriminating normal or viable-germinating corn kernels and soybean seeds from abnormal or dead seeds was also tested. This application could be highly valuable for seed breeders and germplasm-preservation managers because current viability tests are based on a destructive method where the seed is germinated. Heat-damaged corn kernels were best discriminated by PLS-DA, with 99% accuracy. The discrimination of frost-damaged corn kernels was not possible. Discrimination of non-viable seeds from viable also was not possible. Since previous results in the literature contradict the current damage-discrimination results, the threshold of seed damage necessary for NIRS detection should be analyzed in the future. NIRS may accurately classify seeds based on changes due to damage, without any correlation with germination. 相似文献
107.
E. Madrid D. Rubiales A. Moral M. T. Moreno T. Millán J. Gil J. Rubio 《European journal of plant pathology / European Foundation for Plant Pathology》2008,121(1):43-53
A gene that controls resistance to chickpea rust (Uromyces ciceris-arietini) has been identified in a recombinant inbred line (RIL) population derived from an interspecific cross between Cicer arietinum (ILC72) × Cicer reticulatum (Cr5-10), susceptible and resistant to rust, respectively. Both parental lines and all RILs displayed a compatible interaction
but differed in the level of infection measured as Disease Severity (DS) and Area Under the Disease Progress Curve (AUDPC).
Histological studies of the seedlings of resistant parental Cr5-10 line revealed a reduction in spore germination, appressorium
formation, number of haustoria per colony and colony size, with little host cell necrosis, fitting the definition of partial
resistance. A Quantitative Trait Locus (QTL) explaining 31% of the total phenotypic variation for DS in seedlings and 81%
of the AUDPC in adult plants in the field was located on linkage group 7 of the chickpea genetic map. The AUDPC displayed
a bimodal distribution with high frequency of susceptible lines and both the AUDPC and markers showed the same distorted segregation.
Consequently, it was hypothesised that a single dominant gene (proposed as Uca1/uca1) controlled resistance to rust in adult plants. This allowed us to locate the gene on the genetic linkage map. Two Sequence
Tagged Microsatellite Sites (STMS) markers, TA18 and TA180 (3.9 cM apart) were identified that flank the resistance gene.
These findings could be the starting point for a Marker-Assisted Selection (MAS) programme for rust resistance in chickpea. 相似文献
108.
Accuracy levels achieved with differential global positioning system (DGPS) receivers in agricultural operations depend upon
the quality of the correction signal. This study has assessed differential signal error from a Dedicated Base Station, OmniSTAR
VBS, European Geostationary Navigation Overlay System, European reference frame-IP for internet protocol (EUREF-IP) and radio
navigation satellite aided technique (RASANT). These signals were utilized in guidance assisting systems for agricultural
applications, such as tillage, harvesting, planting and spraying, in which GPS receivers were used under dynamic conditions.
Simulations of agricultural operations on different days and at different time slots and simultaneously recording the tractor′s
geo-position from a DGPS receiver and the tractor′s geo-position from a real-time kinematic (RTK) GPS allowed the comparison
of the GPS correction signals. The hardware used for tractor guidance was a lightbar (Trimble model EZ-Guide Plus) system.
ANOVA statistics showed a significant difference between the accuracy of the correction signals from different sources. GPS
correction signal recommendations to farmers depend upon the accuracy required for the specific operation: (a) Yield monitoring
and soil sampling (<1 m) are possible with all the GPS correction signals accessed in any time slot. (b) Broadcast seeding,
fertilizer and herbicide application (<0.5 m) are possible for 80% of time with OmniSTAR VBS, 40% of time with RASANT and
EUREF-IP and 100% of time with a dedicated base station. (c) Transplanting and drill seeding (<0.04 m) are not possible with
the accuracy correction provided by any one of the systems used in this study. 相似文献
109.
Ana Claudia Ochogavía Mercedes Gil Liliana Picardi Graciela Nestares 《Breeding Science》2014,64(4):416-421
Chlorosis level is a useful parameter to assess imidazolinone resistance in sunflower (Helianthus annuus L.). The aim of this study was to quantify chlorosis through two different methods in sunflower plantlets treated with imazapyr. The genotypes used in this study were two inbred lines reported to be different in their resistance to imidazolinones. Chlorosis was evaluated by spectrophotometrical quantification of photosynthetic leaf pigments and by a bioinformatics-based color analysis. A protocol for pigment extraction was presented which improved pigment stability. Chlorophyll amount decreased significantly when both genotypes were treated with 10 μM of imazapyr. Leaf color was characterized using Tomato Analyzer® color test software. A significant positive correlation between color reduction and chlorophyll concentration was found. It suggests that leaf color measurement could be an accurate method to estimate chlorosis and infer chlorophyll levels in sunflower plants. These results highlight a strong relationship between imidazolinone-induced chlorosis and variations in leaf color and in chlorophyll concentration. Both methods are quantitative, rapid, simple, and reproducible. Thus, they could be useful tools for phenotyping and screening large number of plants when breeding for imidazolinone resistance in this species. 相似文献
110.
Sabra Hemidouche Lidia Favier Abdeltif Amrane Patrick Dabert Sophie Le Roux Zahra Sadaoui 《Water, air, and soil pollution》2018,229(3):103
This study provides an alternative solution for the bioremediation of a recalcitrant pharmaceutical micropollutant. Clofibric acid (CLA) was chosen as target molecule, because of its environmental persistence and resistance to wastewater treatment technologies. The aim of this study was to investigate the potential of a phenol-resistant Pseudomonas aeruginosa strain isolated from the activated sludge to degrade CLA. In order to evaluate the effect of acclimation process with glucose as carbon co-substrate, two protocols were performed, in which the transfer of the inoculum is carried out either in the exponential growth phase or in the decline phase. The results showed a removal efficiency of CLA of 35% when cells in the decline phase were used for inoculation. In contrast, a very low removal yield (10%) was achieved when cells harvested in the exponential phase were used as inoculum. This work is the first one reporting on the capability of this bacterium to remove this drug. The obtained data showed that the isolated strain is able to degrade target molecule and might be a promising agent for the elimination of this refractory compound. 相似文献