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941.
Wild capture fisheries produce 90 million tonnes of food each year and have the potential to provide sustainable livelihoods for nearly 40 million people around the world ( http://www.fao.org/3/a-i5555e.pdf ). After decades of overfishing since industrialization, many global fish stocks have recovered, a change brought about through effective management. We provide a synthetic overview of three approaches that managers use to sustain stocks: regulating catch and fishing mortality, regulating effort and regulating spatial access. Within each of these approaches, we describe common restrictions, how they alter incentives to change fishing behaviour, and the resultant ecological, economic and community‐level outcomes. For each approach, we present prominent case‐studies that illustrate behaviour and the corresponding performance. These case‐studies show that sustaining target stocks requires a hard limit on fishing mortality under most conditions, but that additional measures are required to generate economic benefits. Different systems for allocation allow stakeholder communities to strike a locally acceptable balance between profitability and employment.  相似文献   
942.
Commercial and food-type sorghum hybrids with differing kernel and endosperm characteristics were grown under comparable conditions and steam flaked in each of three years. The raw-grain kernel characteristics and proximate analyses were homogenous over the three-year period. The waxy hybrid produced large, translucent, durable flakes that had significantly higher enzyme-susceptible starch values for all years compared to the other varieties. Flakes with lower amylose contents (waxy endosperm) were positively correlated with percent whole flakes (r2 = 0.509), flake diameter (r2 = 0.846), and enzyme-susceptible starches (r2 = 0.564) and negatively correlated with higher flake fragility (r2 = -0.647), test weight (r2 = -0.626), and flake breakage (r2 = -0.560). The heterowaxy flakes had a good appearance and were generally comparable in quality to the nonwaxy commercial and experimental hybrids. Heterowaxy sorghum hybrids with good grain yields can provide improved quality grain and flakes without sacrificing agronomic performance and yields. No difference in flaking performance was detectable among the kernels with different pericarp colors; flakes from the white food-type sorghums had excellent appearance. Nontempered control samples were inferior in quality to all conditioned treatments.  相似文献   
943.
A series of 1,4-benzoxazin-3-ones with a sulfonylurea group attached at either the 5 or 8 position have been synthesised and found to show moderate herbicidal activity. Similarly, a series of 1,4-benzothiazin-3-ones, including some of the related S-oxides and S-dioxides, with a sulfonylurea group linked at the 8 position, have been prepared and been found to be herbicidal. In both series of compounds many substituent variations were made but none of the compounds showed any useful crop selectivities.  相似文献   
944.
945.
前言 从传统角度来看,"肉质"这个词涵盖了决定肉的适口性、深加工能力以及储存(包括零售展示)能力等性状的内在特性.人们主要关注肉的安全性、营养价值、风味、质地、系水力、色泽、脂肪含量及组成、氧化稳定性和质量均一性等.肉质被认为是肉品的一个复杂而多元的特性,主要受管理系统、品种、基因型、饲养、宰前处理、击晕方式、屠宰方法、冷却方法及储藏条件等多种因素相互作用的影响.  相似文献   
946.
Seven yearling bulls were treated with stressful exercise and intrabronchial Pasteurella haemolytica A1. Group 1 bulls (nos. 1–4) underwent treadmill exercise and, 24 days later, intrabronchial instillation of P. haemolytica A1. Group 2 bulls (nos. 5–7) underwent treadmill exercise, followed 30 min later by intrabronchial P. haemolytica A1. Blood lactic acid values were raised (p<0.05) by treadmill exercise only, but plasma cortisol was raised (p<0.05) by treadmill exercise and by P. haemolytica A1 infection. Neutrophils in bronchoalveolar lavage (BAL) differed from control values 24 h after treadmill exercise, and 1 h and 4 h after P. haemolytica A1 infection.Respiratory disease was more severe and the gross lung lesions were larger in group 2 bulls than in group 1 bulls. P. haemolytica A1 was recovered from the livers, spleens and mesenteric lymph nodes of group 2 but not group 1 bulls, suggesting that group 2 bulls had experienced bacteraemia. Decreased neutrophils in BAL fluid from group 2 bulls at 1 h and 4 h after infection suggests that exercise transiently inhibited neutrophil egress from the blood to the alveoli; BAL neutrophils peaked at 1 h and 4 h after infection in group 1 bulls but declined at 24 h. We conclude that group 2 bulls were made more susceptible to experimental pneumonic pasteurellosis by stressful exercise.Abbreviations ADCC antibody dependent, cell-mediated cytotoxicity - AM alveolar macrophages - BAL bronchoalveolar lavage - CFU conlony-forming units  相似文献   
947.
The incidence of lipoid pneumonia in dogs is not known and confirmed cases do not appear to have been reported. Three forms of lipoid pneumonia are recognised in mammalian species; exogenous lipoid pneumonia (ELP), endogenous lipoid pneumonia (EnLP), and post-obstructive endogenous lipoid pneumonia (PEnLP). All forms share similar microscopic characteristics of fat accumulation in the cytoplasm of alveolar macrophages and are otherwise clinically indistinct from other forms of pneumonia. A case of lipoid pneumonia in a seven-year-old rough collie dog which was presented with recurrent bronchopneumonia over several months is reported here. Diagnosis was made from biopsy of resected lung tissue and from detection of fat-containing vacuoles in macrophages obtained by bronchoalveolar lavage. ELP could not be differentiated from PEnLP in this dog, but a complete recovery followed removal of the affected right accessory and caudal lung lobes.  相似文献   
948.
Central core myopathy in a great dane   总被引:3,自引:0,他引:3  
An eight-month-old female great dane was referred for investigation of exercise intolerance that had developed progressively over one month. Examination revealed poor muscle mass, elevated plasma levels of muscle-associated enzymes and electromyographic abnormalities. The dog was euthanased at 15 months old because of severe exercise intolerance. Tissue obtained by biopsy and at post mortem examination revealed prominent well defined central core structures within most muscle fibres, but no other abnormalities. The condition was diagnosed as a central core myopathy.  相似文献   
949.
Sixty-four dogs with histories and clinical signs consistent with cervical intervertebral disk disease were presented for evaluation. Survey spinal radiographs were obtained, followed by myelography. In 61% of the survey radiographs, evaluators identified sites of disk extrusion or protrusion based on radiographic findings. Of those radiographs where a site was identified, ability to accurately identify the correct site of disk extrusion ranged from 53% to 67%, with an average of 58%. Therefore, the overall accuracy rate for correct identification of the site(s) of disk extrusion for all survey radiographs was 35%. Twelve cases had more than one site of disk extrusion or protrusion evident myelographically. In cases where multiple sites of extrusion were confirmed myelographically, the ability to localize at least one of the sites on the corresponding survey radiographs ranged from 63% to 80%, with an average of 70%. The major site of disk extrusion or protrusion was incorrectly identified in 16% to 31% of the survey radiographs, with an average of 26%. The use of survey radiographs alone is an inaccurate means for localization of cervical intervertebral disk extrusion or protrusion.  相似文献   
950.
Lumbar polyradiculopathy, characterized by ballooning myelin sheaths was diagnosed in multiple aged mammalian species including two horses, a cow, a squirrel, a woodchuck, a rabbit, a guinea pig, a hamster, and a mouse. The lesion was subclinical, and considered an incidental, age-related finding.  相似文献   
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