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Tunisian pomegranate genetic resources consist of sweet and sour cultivars, showing large morphometric variability. In the present work we characterized seeds and juice contents of sugars and organic acids of 5 sour and 7 sweet pomegranate cultivars. Results showed that citric acid was predominant in sour pomegranates, while malic acid was the most prevalent in sweet ones. Paradoxically, sour cultivars have higher sugar content than the sweet ones. A strong correlation was found between sourness and citric acid content, which is assumed to be the major factor that determines sour taste in pomegranate fruits. Besides, some of the seed parameters showed a significant positive correlation with acidity. Sweet cultivars were appropriate for fresh consumption and juice production due to several attributes in addition to their sweetness. Equally, sour pomegranate showed several characteristics that could be of great interest for food and nutraceutical industries.  相似文献   
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Hepatic progenitor cells (HPCs) are bipotential stem cells residing in human and animal livers that are able to differentiate towards the hepatocytic or cholangiocytic lineages. HPCs are present in both hepatocellular (HCC) and cholangiocellular carcinoma (CC) in humans; and a small percentage of HCC can originate from cancer stem cells. However, its distribution in canine liver tumour has not been studied. Herein, we searched for stem/progenitor cells in 13 HCC and 7 CC archived samples by immunohistochemical analysis. We found that both liver tumours presented a higher amount of K19‐positive HPCs. Besides, 61.6% of HCC cases presented immature CD44‐positive hepatocytes. Nevertheless, only two cases presented CD133‐positive cells. As observed in humans, hepatic canine tumours presented activated HPCs, with important differentiation onto hepatocytes‐like cells and minimal role of cancer stem cells on HCC. These findings reiterate the applicability of canine model in the search for new therapies before application in humans.  相似文献   
86.
Three different LED lamps with continuous spectra were compared against commonly used fluorescent lights. The lamps were characterized by light output, energy consumption and spectral quality for plant growth. The biological effects of light quality were compared by pre-cultivating seedlings of Picea abies (L.) Karst. and Pinus sylvestris L. under each spectrum for 35 days in a growth chamber with controlled temperature, humidity and photoperiod. The seedlings were then transplanted and cultivated for one vegetation period at the nursery, then planted outdoors on a forest field trial and followed for three years. The seedlings showed similar growth performance for all spectra tested. LED lamps have several advantages to fluorescent light such as energy consumption, longer life span and adjustable light intensity. Regarding light intensity the effects on growth performance were studied for both species using the most promising LED spectra. The photosynthetically active radiation (PAR) was maintained at 50, 100, 200 and 400 μmol?m?2?s?1. Unlike energy consumption, seedling development did not display a linear relationship to light intensity. Instead, the results show an optimum light level between 100 and 200?μmol?m?2?s?1 for the shade tolerant Picea abies seedlings and a level of around 200?μmol?m?2?s?1 for the more shade intolerant Pinus sylvestris seedlings.  相似文献   
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OBJECTIVE: To assess the effect of oral administration of CaCl2 gel on blood mineral concentrations, parturient disorders, reproductive performance, and milk production of dairy cows with retained fetal membranes (RFM). DESIGN: Randomized field trial. ANIMALS: 20 cows that calved normally and were not treated with CaCl2 gel (group 1), 20 cows with RFM that were treated with CaCl2 gel (group 2), and 20 cows with RFM that were not treated with CaCl2 gel (group 3). PROCEDURE: Group-2 cows were treated orally with CaCl2 gel (54 g of calcium) 24 and 48 hours after parturition. RESULTS: Administration of CaCl2 gel 24 and 48 hours after parturition did not have a significant effect on serum normalized calcium, total calcium, magnesium, or phosphorus concentrations or on incidence of metritis or left displacement of the abomasum, days to first insemination, pregnancy status after first insemination, or milk production. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of CaCl2 gel 24 and 48 hours after parturition did not have significant effect on blood mineral concentrations, parturient disorders, reproductive performance, and milk production in dairy cows with RFM.  相似文献   
88.
应用HLB固相萃取高效液相色谱-质谱法同时测定水中杀虫剂、杀菌剂、除草剂、杀螨剂、杀线虫剂等5类30种农药残留,标准曲线决定系数r2均大于0.99,标准添加回收率达76% ̄107%,平均为87.9%。在实际测定的10个水样中,有个水样的杀铃脲(Triflumuron)含量超标。  相似文献   
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The timing of recurring biological and seasonal environmental events is changing on a global scale relative to temperature and other climate drivers. This study considers the Gulf of Maine ecosystem, a region of high social and ecological importance in the Northwest Atlantic Ocean and synthesizes current knowledge of (a) key seasonal processes, patterns, and events; (b) direct evidence for shifts in timing; (c) implications of phenological responses for linked ecological‐human systems; and (d) potential phenology‐focused adaptation strategies and actions. Twenty studies demonstrated shifts in timing of regional marine organisms and seasonal environmental events. The most common response was earlier timing, observed in spring onset, spring and winter hydrology, zooplankton abundance, occurrence of several larval fishes, and diadromous fish migrations. Later timing was documented for fall onset, reproduction and fledging in Atlantic puffins, spring and fall phytoplankton blooms, and occurrence of additional larval fishes. Changes in event duration generally increased and were detected in zooplankton peak abundance, early life history periods of macro‐invertebrates, and lobster fishery landings. Reduced duration was observed in winter–spring ice‐affected stream flows. Two studies projected phenological changes, both finding diapause duration would decrease in zooplankton under future climate scenarios. Phenological responses were species‐specific and varied depending on the environmental driver, spatial, and temporal scales evaluated. Overall, a wide range of baseline phenology and relevant modeling studies exist, yet surprisingly few document long‐term shifts. Results reveal a need for increased emphasis on phenological shifts in the Gulf of Maine and identify opportunities for future research and consideration of phenological changes in adaptation efforts.  相似文献   
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Hypoxic ascites in broilers: a review of several studies done in Colombia   总被引:2,自引:0,他引:2  
A Hernandez 《Avian diseases》1987,31(3):658-661
In Bogotá, Colombia, broilers developed ascites due to pulmonary hypertension of hypoxic origin at 2638 m above sea level. This disease has tremendous economic impact in various countries of the world and is characterized by pulmonary hypertension, hypertrophy and hyperplasia of the right ventricle of the heart, increased hematocrit and hemoglobin values, and ascites. This entity appears to be influenced by management practices and by inability of broilers to adapt to high altitude.  相似文献   
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