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191.
OBJECTIVE: To establish the school eating habits of Mexican children, who are prone to obesity and later to high rates of adult chronic diseases. DESIGN: Questionnaires for students and parents with staff questionnaires and interviews. SETTING: Randomly sampled schools in a socio-economically representative district of Mexico City. SUBJECTS: Subjects were 1504 adolescents aged 10-19 years attending schools in Mexico City, 27 teachers and seven headmasters, sampled from both public and private schools and from the full range of socio-economic groups. RESULTS: Foods brought from home were of a higher nutritional quality than those purchased at school, where purchases were dominated by crisps, soft drinks and other items with high energy density. Girls were more inclined to purchase inappropriately; those from poorer homes purchased less. Private-school students irrespective of socio-economic grade brought more food from home and purchased more expensive food at school. School policies allowed food and drink vendors to market any products within the schools, which benefited financially from these activities. CONCLUSIONS: Current school food policies are conducive to amplifying the current epidemic of obesity and related adult chronic diseases, and need to change.  相似文献   
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The measurement of soil erosion rates under natural rainfall conditions is costly and time consuming. Data provided by rainfall simulation and static site measurements can be used to predict erosion rates under natural conditions, however the accuracy of this method is largely untested. This is especially true for erosion rates from unsealed forest roads. In this study, the values for a range of erodibility indices calculated from rainfall simulation experiments are compared to observed erodibility index values from 1 year of detailed in-situ erosion monitoring of seven different forest road types. The prediction of phosphorus generation rates from rainfall simulation and/or soil sampling was also evaluated. The results showed that a series of commonly used erodibility indices such as sediment per unit rainfall, sediment per unit runoff, sediment per unit EI30, and sediment per unit rainfall energy were poorly predicted from the rainfall simulation experiments. Five of the six indices tested substantially overpredicted the observed erodibility at one site, a gravel road subjected to minimal traffic. For the other six road sites predictions were poor and highly variable, the coefficient of efficiency ranging from − 13.32 to 0.17 for these erodibility indices. A modified index, the ratio of sediment per unit rainfall energy to the mean rate of rainfall energy input, was able to predict annual erosion rates from six different road surfaces using rainfall simulation data with a coefficient of efficiency of 0.9. The results indicate that existing erodibility indices are not suitable for predicting observed erosion rates on forest roads using rainfall simulation data as collected in this study. It is argued that the modified index is more suited to sites (such as compacted roads) where interrill processes dominate, and erosion rates are less sensitive to peak flows. With respect to nutrient generation rates, rainfall simulation was able to accurately predict the observed proportion by mass of total phosphorus (TP) in runoff with a coefficient of efficiency of 0.96. Direct soil sampling of the road surface could also be used to predict the proportion by mass of TP in runoff. Concentrations of total nitrogen in forest road materials were found to be at the lower detection limit of the laboratory instruments.  相似文献   
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This article reviews the history of public-health education at the University of California, Davis, from the inception of the Master of Preventive Veterinary Medicine Program in the School of Veterinary Medicine through the creation of the Master of Public Health Program offered jointly by the Schools of Medicine and Veterinary Medicine. The long history of collaborative teaching and research between the schools, as well as the university's close proximity to and relationship with numerous university-affiliated and state public-health agencies, has created remarkable opportunities for novel and creative public-health education. The university is already anticipating the approval of a School of Public Health on its campus, which will create even more educational opportunities in both human and veterinary public-health disciplines. Given the projected shortfall of veterinarians entering such fields, the opportunity of a novel Doctor of Public Health degree program specifically suited to the needs of veterinary medicine is also discussed as a means of addressing this shortage.  相似文献   
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Objective  Local photodynamic therapy (PDT) is a novel cancer therapy in veterinary ophthalmology. A prospective pilot study seeking to demonstrate proof of principle and safety for the treatment of equine periocular squamous cell carcinoma (PSCC) was therefore conducted. We hypothesized that surgical excision with adjunctive local PDT is an effective and safe treatment for equine PSCC.
Procedures  Nine horses (10 eyes) with PSCC were treated with surgical resection, local infiltration of resulting wound beds with 2-[1-hexyloxyethyl]-2-devinylpyropheophorbide-a (HPPH) and irradiation with 665-nm wavelength diode laser. Regular follow-up ophthalmic examinations were performed.
Results  Surgical resection and PDT yielded disease-free intervals of 25–68 months in our study horses as of January, 2008. These results were obtained following a single treatment in seven horses and two treatments in one horse. In one horse, carcinoma in situ developed 2.5 months after partial surgical excision and PDT, requiring local excision under standing sedation.
Conclusions  Preliminary results suggest that surgical resection and adjunctive local PDT is a safe and effective novel treatment for PSCC in horses. More research is needed before PDT for the treatment of equine PSCC can be adequately compared with other current modalities. Important to future investigations regarding PDT, tumor recurrence rate, length of hospitalization, number of treatment episodes required to effect tumor remission, and total treatment costs should be examined in a controlled manner. Our present results and experiences suggest that this treatment may be useful in the treatment of equine PSCC.  相似文献   
198.
The objective of the current study was to describe and characterize the pharmacokinetics and selected pharmacodynamic effects of morphine and its two major metabolites in horses following several doses of morphine. A total of ten horses were administered a single intravenous dose of morphine: 0.05, 0.1, 0.2, or 0.5 mg/kg, or saline control. Blood samples were collected up to 72 hr, analyzed for morphine, and metabolites by LC/MS/MS, and pharmacokinetic parameters were determined. Step count, heart rate and rhythm, gastrointestinal borborygmi, fecal output, packed cell volume, and total protein were also assessed. Morphine‐3 glucuronide (M3G) was the predominant metabolite detected, with concentrations exceeding those of morphine‐6 glucuronide (M6G) at all time points. Maximal concentrations of M3G and M6G ranged from 55.1 to 504 and 6.2 to 28.4 ng/ml, respectively, across dose groups. The initial assessment of morphine pharmacokinetics was done using noncompartmental analysis (NCA). The volume of distribution at steady‐state and systemic clearance ranged from 9.40 to 16.9 L/kg and 23.3 to 32.4 ml min?1 kg?1, respectively. Adverse effects included signs of decreased gastrointestinal motility and increased central nervous excitation. There was a correlation between increasing doses of morphine, increases in M3G concentrations, and adverse effects. Findings from this study support direct administration of purified M3G and M6G to horses to better characterize the pharmacokinetics of morphine and its metabolites and to assess pharmacodynamic activity of these metabolites.  相似文献   
199.
The western barred bandicoot, Perameles bougainville, is an endangered Australian marsupial species. Routine histology of liver samples collected at necropsy from 19 of 20 (95%) western barred bandicoots revealed the sporadic to common occurrence of abnormal hepatocyte nuclei characterized by margination of chromatin and concomitant central pallor. Some abnormal hepatocyte nuclei were mildly to markedly enlarged and irregularly shaped. Periodic acid-Schiff reagent stained 131 of 142 (92%) of these abnormal hepatocyte nuclei. Positive staining was completely eliminated by diastase pretreatment. Transmission electron microscopy revealed that abnormal hepatocyte nuclei with marginated chromatin did not contain viral particles. Rather, glycogen beta-particles and alpha-rosettes were identified within some abnormal hepatocyte nuclei. Glycogen intranuclear inclusions were an incidental finding in western barred bandicoot hepatocytes.  相似文献   
200.
A spotlight on snow leopard conservation in China   总被引:1,自引:0,他引:1       下载免费PDF全文
China holds the greatest proportion of the snow leopard's (Panthera uncia) global range and is central to their conservation. The country is also undergoing unprecedented economic growth, which increases both the threats to the snow leopard and the opportunities for its conservation. In this paper we aim to review published literature (from 1950 to 2014) in English and Mandarin on snow leopard ecology and conservation in China in order to identify thematic and geographic research gaps and propose research priorities. We first retrieved all published items that considered snow leopards in China (n = 106). We extracted from these papers 274 reports of snow leopard presence in China. We then reviewed a subset of papers (n = 33) of this literature, which specifically focused on snow leopard ecology and conservation within China. We introduced a thematic framework that allows a structured and comprehensive assessment of findings. This framework recognizes 4 critical and interrelated topics underpinning snow leopard ecology and conservation: habitat (distribution and protected area coverage); prey (distribution and abundance, predator–prey relationships); human interactions (hunting and trade, livestock interactions and conflicts); and the underlying policy context. Significant gains in knowledge as well as research gaps and priorities are discussed with reference to our framework. The modest quantity and limited scope of published research on the snow leopard in China calls for a continued and intensified effort to inform and support national conservation policies.  相似文献   
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