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31.
32.
Three 0.01m Fe(ClO4)3 Solutions of R= 0, 1, and 2, respectively, were studied over a period of 8 months, where R is referred to the HCO3?/Fe3+ mole ratio in preparation. The R= 0 solution was initially light yellow and clear but rapidly changed to a dense cloudy Suspension after a 9-day induction period. Hydrolysed species rapidly grew from <10 nm to >650 nm. Particles of intermediate size were not observed during the entire period of study. Settleable FeOOH precipi-tate was first observed in 5 weeks with 23 per cent of its iron noted as precipitate at the end of 5 months. The R= 1 and R= 2 Solutions were reddish-brown of low turbidity. Rapid hydrolysis and polymerization were observed immediately after preparation. The hydrolysed species gradually grew in size during ageing and no settleable FeOOH precipitate was observed for at least two years. A hypo-thesis based on Lamb and Jacques's model of Fe3+ hydrolysis is proposed to interpret the reactions taking place in these three Solutions. In the R= 0 solution, the initial number of nuclei for condensation is low, whereas the poten-tial supply of Fe(OH)3 is abundant. In the R= 1 and R= 2 Solutions the number of nuclei initially formed is high, whereas a limited amount of mono-meric Fe(OH)3 is available for condensation. The initial number of nuclei relative to the concentration of monomeric species is the key factor that governs the appearance and properties of these Solutions. 相似文献
33.
P Hedenqvist DVM HE Orr† BVMS Cert LAS JV Roughan† BSc PhD LM Antunes† MSc DVM & PA Flecknell† M.A Vet MB PhD DLAS Dip ECVA MRCVS 《Veterinary anaesthesia and analgesia》2002,29(1):14-19
Objective To compare the characteristics of anaesthesia induced with ketamine/medetomidine administered by the subcutaneous and intramuscular routes and to assess the effects of the addition of butorphanol to this combination. Study design Prospective randomised study. Animals Six female New Zealand White rabbits. Methods Rabbits were given one of four combinations of ketamine and medetomidine (K/M) either subcutaneously (SC) or intramuscularly (IM) on four successive occasions with a 7‐day interval between treatments. The dose combinations were; 15/0.25 mg kg?1 SC; 15/0.25 mg kg?1 IM; 15/0.5 mg kg?1 SC, and 15/0.25 mg kg?1 together with 0.4 mg kg?1 butorphanol (K/M/B) SC. The effects of anaesthesia on arterial blood gas values and cardiovascular variables were recorded at predetermined time points. Toe and ear pinch reflexes were judged to determine the duration of surgical anaesthesia. Loss of the righting reflex was used to measure the duration of sleep time. Analyses used repeated measures analysis of variance. Results All groups lost the righting reflex and ear pinch response. Three animals in the groups that received K/M alone lost their toe pinch reflex, whereas four lost this reflex when given K/M/B. Time of onset of loss of the righting, toe and ear pinch reflexes did not differ significantly among the groups. The higher dose combination of medetomidine with ketamine and the combination of K/M/B produced a greater duration of loss of the ear pinch response than the lower dose of K/M administered by either route. No significant differences were found among the groups in the duration of loss of the toe pinch reflex. All animals developed a moderate bradycardia (mean heart rate <166 beats minute?1) and moderate hypoxaemia (mean PaO2 < 6.0 kPa). Animals given butorphanol showed the greatest reduction in respiratory rate (31 ± 13 breaths minute?1, p < 0.05) but this was not reflected in any significant differences in arterial PCO2, PO2 or pH among the groups. Conclusions Administration of K/M by the SC route produced equivalent effects in comparison to intramuscular administration. The addition of butorphanol increased the duration of anaesthesia, but produced a slight increase in the degree of respiratory depression. All dose rates resulted in hypoxaemia so oxygen should be administered when these combinations are used in rabbits. Clinical relevance Subcutaneous administration is both technically simpler and may cause less discomfort to the animal than IM injection, and so is preferred. The combination of K/M with butorphanol has relatively minor effects on the depth and duration of anaesthesia, so offers little advantage to the use of K/M alone. 相似文献
34.
帕提曼 《农业图书情报学刊》2013,(11):172-175
分析了高校图书馆流通服务和赢利性企业的共性,论述了高校图书馆流通服务管理应用“关键时刻”管理理论的可行性和必要性。提出了通过对高校图书馆流通服务中的一系列“关键时刻”的强化管理.提高流通服务质量,最大限度地满足读者需求的策略。 相似文献
35.
AbstractCASE HISTORY: One 4.5-month-old male Border Collie cross presented with aggression and seizures in October 2006. A 16-month-old, female, spayed Border Collie cross presented with hypersalivation and a dropped jaw and rapidly became stuporous in September 2007. The dogs were littermates and developed acute neurological signs 5 and 27 days, respectively, after vaccination with different modified live vaccines containing canine distemper virus.HISTOPATHOLOGICAL FINDINGS: Sections of brain in both dogs showed evidence of encephalitis mainly centred on the grey matter of brainstem nuclei, where there was extensive and intense parenchymal and perivascular infiltration of histiocytes and lymphocytes. Intra-nuclear and intra-cytoplasmic inclusions typical of distemper were plentiful and there was abundant labelling for canine distemper virus using immunohistochemistry.DIAGNOSIS: Post-vaccinal canine distemper.CLINCIAL RELEVANCE: Post-vaccinal canine distemper has mainly been attributed to virulent vaccine virus, but it may also occur in dogs whose immunologic nature makes them susceptible to disease induced by a modified-live vaccine virus that is safe and protective for most dogs. 相似文献
36.
Acacia koa forests benefit from phosphorus fertilisation, but it is unknown if fertilisation is a short or long term effect on P availability. Past research suggests that P cycling in soils with high P sorption capacity, such as Andisols, was through organic pathways. We studied leaf P and soil P fractions in a tropical forest Andisol for 3 years after fertilisation with triple super phosphate. Leaf P concentration and labile P remained high after fertilisation. Fertilisation had increased all the inorganic P fractions over the length of the study, while organic P fractions had not. The results suggested that the organic P fractions had a reduced role as a source of labile P after fertilisation. The size and dynamics of the sodium hydroxide- and hydrochloric acid-extractable P pools would suggest that either pool could be major sources of labile P. Because of the high level of poorly crystalline minerals in Andisols (allophone and imogolite), it would be expected that applied P would quickly lead to strong P sorption onto mineral surfaces and thus a rapid decline in P availability. We propose that the high organic matter present in these soils had masked some of the Al and Fe sorption sites, which allowed the sorption and desorption when large amounts of addition P were applied. 相似文献
37.
T. Walker J. Friday M. Casimero R. Dollentas A. Mataia R. Acda R. Yost 《Agricultural Systems》2009,101(3):162-172
Maize is the most important crop in upland areas in the Philippines, but production lags behind potential in many areas, especially those with acid soils. The Nutrient Management Support System (NuMaSS), a computer-based decision aid, provides soil and crop-based recommendations for nutrient amendments and lime. Development and trials of the NuMaSS were carried out on upland maize farms in Isabela province in the northern Philippines from 1998 to 2006. While local practices and standardized government recommendations had included applying N, P, and K, the application of lime to correct soil acidity had not been practiced locally and lime was not commercially available in local markets. Based on data from 39 field trials on 13 different farms over four years, we calculate that liming increased maize grain yield on the average by 1.5 t/ha. A farmer purchasing and applying lime would realize a single-season marginal rate of return on investment of about 160%. Because of the positive results of the on-farm trials of the NuMaSS, and in particular the positive result of liming acid soils, the Philippine Department of Agriculture began a lime promotion program in four provinces in Region II in 2006. The program includes field days, farm-level demonstrations, and distribution of subsidized lime to farmer-cooperators. We estimate the economic value of the NuMaSS and lime promotion program to have an NPV of $8 million or an IRR of 25%. We base our calculations on the costs for the research program itself, the costs of the extension program, the costs of the subsidized inputs for the first four years, and the benefits of improved maize production over a 40 year horizon over 12,000 ha (out of a potential 90,000 ha of acid soils in maize production). Our calculations show that the NPV of the lime promotion increases with increasing adoption but the program has a positive NPV even if adoption is negligible after the initial promotional program ceases. Our results document the adoption and farm level and regional economic impact of a decision aid. As agriculture in the Philippines and other developing countries expands with increasing food prices and other demands such as bioenergy production, farmers will need better decision tools such as the NuMaSS to manage crop production on problem soils and marginal sites. 相似文献
38.
PAW HARPER RW COOK† PA GILL† GC FRASER† LM BADCOE‡ JM POWER§ 《Australian veterinary journal》1993,70(4):140-144
SUMMARY The epidemiological, clinical and pathological features of a disease syndrome in adult cattle grazing woolly-pod vetch (Vicia villosa ssp dasycarpa) or popany vetch (V benghalensis) are reported. Outbreaks of toxlcosis occurred between midwinter and midsummer in 3 dairy and 6 beef herds on the north coast of New South Wales, between 1982 and 1992. Friesian, Angus, Murray Grey, Guernsey and Hereford breeds were affected. Mean morbidity and case fatality rates in affected herds were 7% (65 of 889) and 69%, respectively. Signs of pruritic dermatitis, illthrift and death were associated with an eosinophilic granulomatous inflammation of many organs, particularly involving the renal cortex, dermis, myocardium, adrenal glands, lymph nodes and hepatic portal triads. 相似文献
39.
Budgerigars ( Melopsittacus undulatus ) from two different breeding colonies were found to have Giardia infection. Light microscopy, scanning electron microscopy and in-vitro and in-vivo studies confirmed the species was G psittaci . Chicks were clinically affected and showed signs of retarded growth, dehydration and diarrhoea. The faeces of adult birds treated with metronidazole in drinking water were negative for Giardia 5 days after treatment. Megabacteria were also found in adult birds but were not treated. This study extends the known host range for Giardia in Australia to include budgerigars. 相似文献
40.
Joseph O. AyoTavershima Dzenda DVM MSc Friday O. Zakari DVM 《Journal of Equine Veterinary Science》2008
Six Nubian pack donkeys were used to determine variations in rectal temperature (RT), respiratory rate (RR), and heart rate (HR) during the early rainy season. The donkeys exhibited a diurnal range of RT, RR, and HR of 34.7 to 38.7°C, 15 to 75 breaths/minute, and 36 to 72 beats/minute, respectively, with peak mean values at 2:00 pm and a trough shortly after sunrise (7:00 am). The amplitude of the diurnal rhythm of RT and RR was not correlated with the diurnal range of ambient temperature (AT) and relative humidity (RH). Although mean diurnal RTs were positively correlated with corresponding ATs, mean daily RTs were not significantly correlated with corresponding ATs. Diurnal and daily variations in RT of donkeys, like those of other ungulates, therefore, appear to reflect an endogenous rhythm, which may be largely independent of fluctuations in environmental thermal load. The mean maximum AT and RH, and the corresponding RR and HR values, fell above the normal range for donkeys in the tropics. The season was meteorologically stressful to the donkeys, imposing significant changes in the RT, RR, and HR parameters requiring responses to maintain homeostasis. The values of the amplitude in RT, RR, and HR obtained in individual donkeys were higher than the corresponding values obtained during the hourly recordings, indicating that it is more important to evaluate the individual's vital parameters in reaching conclusion of fitness for work in donkeys. The hourly recordings have shown the hours of the day (11:00 am to 4:00 pm) that are potentially meteorologically stressful for donkeys to be used for packing during the season. 相似文献