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231.
Management of black bears (Ursus americanus) in urban settings is of growing concern because they often recolonize areas from which they had been extirpated. Urban landscapes offer much needed bear habitat, buffer habitat losses in other areas, and offer protection for bear populations, but only if conflicts between bears and humans are managed. In collaboration with the Northern Bear Awareness Society in Prince George, British Columbia, Canada, a survey of a sample of Prince George residents was conducted to determine their attitudes toward black bears and bear management, including euthanasia (N = 71). These residents tended to feel positively toward black bears, but were split on the issue of euthanasia, with half being firmly opposed and half recognizing the need under certain conditions. There was a significant preference for non-lethal management tools, suggesting an opportunity for governments to explore options for managing human activities that created bear attractants.  相似文献   
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An aged miniature pony was referred for chronic recurrent oesophageal obstruction. Endoscopic examination demonstrated distal oesophageal constriction and radiography confirmed an irregular soft tissue mass in the region of the distal intrathoracic oesophagus. The pony was subjected to euthanasia and post mortem examination confirmed squamous cell carcinoma of the distal oesophagus and stomach. Oesophageal squamous cell carcinoma is a rare condition in horses, but should be considered as a differential diagnosis in cases of chronic recurrent obstruction, particularly in older horses.  相似文献   
233.
Haematological and biochemical data were collected over a period of six years from grey seal (Halichoerus grypus) pups undergoing rehabilitation. Pups bled during the first three days were allocated retrospectively to one of seven clinical groups and statistical analyses were carried out on six of these groups (130 pups). Compared with reference ranges, all the groups had lower mean packed-cell volumes (pcv), red blood cell (rbc) counts haemoglobin and albumin levels, pups with severe trauma had higher total white blood cell (wbc) and neutrophil counts, pups with severe trauma and malnourished pups had higher total bilirubin levels, and pups in all the clinical groups except those with severe trauma had lower sodium levels. There were significant differences (P<0.05) between some clinical groups for mean pcv, rbc counts, all wbc counts except monocytes, haemoglobin, total bilirubin, creatine kinase, amylase and potassium levels. Forty-nine pups were bled more than once during the first 10 days of rehabilitation for haematology, and 11 were bled more than once for biochemistry. There were significant decreases (P<0.05) during this period in pcv, and in the activities of alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, creatine kinase and lactate dehydrogenase, and significant increases in all wbc counts, total protein, globulin, amylase and calcium levels.  相似文献   
234.
The ability of the anesthetics metomidate hydrochloride and tricaine methanesulfonate (MS-222) to mitigate the cortisol stress response of Channel Catfish Ictalurus punctatus was evaluated during a 10-min confinement stress. The cortisol concentrations of Channel Catfish anesthetized in metomidate hydrochloride remained consistent throughout the 10-min exposure; however, for fish anesthetized with MS-222 and nonanesthetized fish, cortisol concentrations were approximately 7- and 22-fold higher, respectively, than the baseline concentrations. While both anesthetics reduced cortisol concentrations relative to those of nonanesthetized fish, these results suggest that MS-222 is an appropriate anesthetic to use during the initial 5 min of sedation and that metomidate hydrochloride is appropriate for longer periods of sedation.

Received November 18, 2014; accepted April 9, 2015  相似文献   

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We validated a whole-body cortisol extraction technique for channel catfish, Ictalurus punctatus, fry. Three volume enhancement methods were tested: CAL method (zero calibrator A diluent added to lipid extract), PBS method (phosphate buffered saline added to lipid extract), and VO method (food grade vegetable oil added to lipid extract). The volume enhancement extracts were evaluated using a commercial radioimmunoassay kit. Sensitivity, accuracy, precision, reproducibility, and parallelism could not be determined for the PBS method as cortisol levels were not detected in any of the extracted samples. Intra-assay coefficient of variation (CV) for the CAL and VO methods were 7.3 and 8.3%, respectively, while inter-assay CV were 9.6 and 10.6%, respectively. Based on the sensitivity, accuracy, precision, reproducibility, and parallelism results, we conclude that the CAL method is the most appropriate method for volume enhancement of catfish fry lipid extract. Using the CAL method to detect cortisol in catfish fry, fish were stressed daily for 2 weeks. Fry weights were similar throughout the study while whole-body cortisol levels were higher (P < 0.01) in stressed fish after 1 day of stress. These data show the CAL method can effectively measure whole-body cortisol in catfish fry.  相似文献   
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Changes of carbon stocks in bamboo stands in China during 100 years   总被引:4,自引:0,他引:4  
Bamboo stands are one of the most important forest types in China, covering an area of about 4.99 million hectares, and estimation of their carbon stocks is vital for China's national carbon accounting. Bamboo biomass and carbon fraction, as well as soil bulk density and soil organic matter content, data were collated from 40 publications describing conditions at 35 sites in 10 Chinese provinces where most bamboo stands are distributed. Carbon stocks and its changes in the living biomass and soil organic matter in bamboo stands in China in the past five decades were estimated based on these collated data together with the area of bamboo stands and number of bamboo culms derived from the National Forestry Inventory (NFI). Our estimates indicate that the carbon stocks in bamboo stands in China have been increasing since the 1950s with estimated values of 318.55 Tg  C (1950–1962), 427.37 Tg C (1977–1981), 463.80 Tg C (1984–1988), 493.00 Tg C (1989–1993), 548.79 Tg C (1994–1998) and 631.58 Tg C (1999–2003) accompanying the increase of bamboo stand area. Based on correlation between forest area and bamboo area, as well as the trends of forest area predicted in government strategy documents for forest development over the next five decades, the carbon stocks in bamboo stands for 2010, 2020, 2030, 2040 and 2050 are estimated to be 727.08 Tg C, 839.16 Tg C, 914.43 Tg C, 966.803 Tg C and 1017.64 Tg C, respectively.  相似文献   
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