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81.
82.
Weston B. Johnson Wajira S. Ratnayake David S. Jackson Kyung‐Min Lee Timothy J. Herrman Scott R. Bean Stephen C. Mason 《Cereal Chemistry》2010,87(6):524-531
Dent corn (Zea mays L.) and sorghum (Sorghum bicolor L. Moench) sample sets representative of commonly grown hybrids and diverse physical attributes were analyzed for alkaline cooking performance. The influence of kernel characteristics including hardness, density, starch properties (thermal, pasting, and crystallinity), starch content, protein content, and prolamin content on alkaline cooking performance was also determined. Corn nixtamal moisture content was lower for hard, dense kernels with high protein contents; sorghum nixtamal moisture content was lower for kernels with low moisture contents and low starch relative crystallinities. Statistically significant (P < 0.05) regression equations showed that corn nixtamal moisture content was influenced by TADD (tangential abrasive dehulling device) index, kernel moisture content, starch content, and protein content; sorghum nixtamal moisture content was influenced by starch relative crystallinity, kernel moisture content, and abrasive hardness index. Pericarp removal was not strongly correlated with kernel characterization tests. Location (environmental) and hybrid (genetic) factors influenced most kernel characteristics and nixtamalization processing variables. 相似文献
83.
84.
W Mason 《New Zealand veterinary journal》2013,61(3):163-167
AbstractCASE HISTORY: During the 2014/2015 season 823 predominantly Holstein-Friesian cows calved on a pasture-based farm in the Waikato region of New Zealand. A high prevalence and recurrence rate of lameness had been noted for several years but cows feet were not routinely picked up and therapeutically trimmed.CLINICAL FINDINGS: At a farm visit in December 2015, 23 cows feet were examined and 18/23 (78%) cows had white line disease and 17/23 (74%) sole haemorrhages, as well as severely overgrown and misshapen hooves.EPIDEMIOLOGICAL INVESTIGATION: Lameness, culling and reproductive data were collected for the farm for the period from 01 July 2014 to 30 November 2015. In the 2014/2015 season, 207/823 (25.2%) cows were recorded lame, and in the first half of the 2015/16 season 120/850 (14%) cows were recorded lame. Of the cows recorded lame, 52/207 (25.1%) in the 2014/15 season had >1 case of lameness, and 39/120 (32.5%) cows recorded lame in the 2015/2016 season had been lame in the previous season. There was an apparent increase in prevalence between 29–37 weeks post-calving. Cows >7-years-old had seven times the odds of being recorded as lame compared to 2–3-year-old cows (p<0.001). Lameness was not associated with culling, empty rate or days to conception (p>0.3).DIAGNOSIS: No direct cause for the lameness could be determined.CONCLUSIONS AND CLINICAL RELEVANCE: It was hypothesised that, along with the degenerative changes in the pedal bone as dairy cows increased in age, suboptimal treatment and overgrowth of hooves resulted in permanent changes in the cows feet, resulting in a high prevalence of lameness in older cattle and a high recurrence rate of lameness within and between seasons. This case highlights the importance of prompt identification and treatment of lame cattle. 相似文献
85.
D.L. Harrison B.Sc. C.G.W. Mason M.Sc. A.M.I.Chem.E. 《New Zealand veterinary journal》2013,61(5):120-125
Extract Preservatives in this class are balanced mixtures of soluble salts in which arsenate is the main toxicradical. When timber is impregnated with these solutions and dried, the salts are deposited amongst the wood fibres as microcrystalline compounds which are relatively insoluble. The proportions of the salts in the treating solutions and their interactions during the drying period determine how firmly the toxic ingredients will be; fixed in the wood. For timber that will be subjected to severe conditions of weathering and ground contact use, as is the case with fence posts, good retention of arsenic against leaching is essential. It follows, therefore, that the greater the degree of fixation of an arsenical preservative for fence-post treatment, the less will be the hazard to exposed livestock. 相似文献
86.
We conducted a mark-recapture study of three subpopulations of Craugastor punctariolus at a mid-elevation site in central Panama between 1999 and 2005. The study spans a period over which the pathogenic fungus Batrachochytrium dendrobatidis (Bd) was absent from the site, invaded the site and decimated all amphibian populations, and now persists. We quantified natural demographic parameters prior to and during an event of mass mortality due to chytridiomycosis caused by Bd. Prior to the event of mass mortality, all three subpopulations of C. punctariolus were large (19-68 animals/200 m), showed a stable age-size distribution, and had high survival. All age-size classes of this species co-occurred on boulder clumps along streams, and adults showed high site fidelity and were likely territorial. Following detection of Bd at this site in late September 2004, four dead C. punctariolus were found infected with Bd and all three subpopulations completely disappeared from this site within 2 months. The association of all age-size classes with microhabitats appropriate for survival and growth of Bd likely contributed to the rapid and severe degree of decline of this species at this site. These data provide insight into the patterns and mechanisms of decline within a species due to Bd. 相似文献
87.
Amory JR Barker ZE Wright JL Mason SA Blowey RW Green LE 《Preventive veterinary medicine》2008,83(3-4):381-391
The milk yields of 1824 cows were used to investigate the effect of lesion-specific causes of lameness, based on farmer treatment and diagnosis of lame cows, on milk yield. A three-level hierarchical model of repeated test day yields within cows within herds was used to investigate the impact of lesion-specific causes of lameness (sole ulcer, white line disease, digital dermatitis and other causes) on milk yield before and after treatment compared with unaffected cows. Cattle which developed sole ulcer (SU) and white line disease (WLD) were higher yielding cattle before they were diagnosed. Their milk production fell to below that of the mean of unaffected cows before diagnosis and remained low after diagnosis. In cattle which developed digital dermatitis (DD) there was no significant difference in milk yield before treatment and a slightly raised milk yield immediately after treatment. The estimated milk loss attributable to SU and WLD was approximately 570 and 370 kg, respectively. These results highlight that specific types of lameness vary by herds and within herds they are associated with higher yielding cattle. Consequently lesion-specific lameness reduction programmes targeting the cow and farm specific causes of lameness might be more effective than generic recommendations. They also highlight the importance of milk loss when estimating the economic impact of SU and WLD on the farms profitability. 相似文献
88.
Lydia M Attard Ramon A Carreno Jean A Paré Andrew S Peregrine Christopher J Dutton Thomas R Mason 《Journal of zoo and wildlife medicine》2008,39(3):488-492
A die-off occurred in a captive colony of blue-winged grasshoppers (Tropidacris collaris) at the Toronto Zoo. One fourth of the colony died within a year due to infection with worms initially mistaken for nematomorphs but later identified as nematodes belonging to the Mermithidae, genus Mermis. Mortality persisted and the grasshopper population dwindled over the following years. Mermithid larvae developed in the hemocoel of the insects until they eventually emerged from a hollowed-out exoskeleton. Circumstantial evidence suggests that the parasites were introduced with raspberry browse that was grown on site and contaminated with mermithid eggs. 相似文献
89.
90.
Therese M. McBeath Vadakattu V. S. R. Gupta Rick S. Llewellyn Sean D. Mason Christopher W. Davoren Raymond L. Correll Ben Jones Anthony M. Whitbread 《Journal of Agronomy and Crop Science》2019,205(6):635-646
A primary driver of the wheat yield gap in Australia and globally is the supply of nitrogen (N) and options to increase N use efficiency (NUE) are fundamental to closure of the yield gap. Co‐application of N with phosphorus (P) is suggested as an avenue to increase fertiliser NUE, and inputs of N and P fertiliser are key variable costs in low rainfall cereal crops. Within field variability in the response to nutrients due to soil and season offers a further opportunity to refine inputs for increased efficiency. The response of wheat to N fertiliser input (0, 10, 20, 40 and 80 kg N ha‐1) under four levels of P fertiliser (0, 5, 10 and 20 kg P ha?1) was measured on three key low rainfall cropping soils (dune, mid‐slope and swale) across a dune‐swale system in a low rainfall semi‐arid environment in South Australia, for three successive cropping seasons. Wheat on sandy soils produced significant and linear yield and protein responses across all three seasons, while wheat on a clay loam only produced a yield response in a high rainfall season. Responses to P fertiliser were measured on the sandy soils but more variable in nature and a consistent effect of increased P nutrition leading to increased NUE was not measured. 相似文献