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41.
An experiment was carried out to determine the effects of season (dry and rainy), location (lowland and highland villages)
and breed (local and improved) on the amount and physical and chemical composition of the scavenged feed. This was done by
crop content analysis of a total of 192 Ri (local) and 192 Luongphuong (LP, improved) hens at 20 weeks of age. The mean fresh
weights of the crop contents were 16.9 and 33.3 g, for the dry and rainy seasons, respectively (p < 0.001), 24.3 and 25.9 g, for the Ri and LP breeds, respectively (p < 0.001), and 25.0 and 25.3 g, for the lowland and highland village, respectively (p > 0.05). The proportions of contents were human food leftovers 38.4% and 24.3%, grains 20.9% and 33.7%, insects and worms
9.6% and 11.2%, and green materials 8.8% and 13.8%, for the dry and rainy seasons, respectively (p < 0.05). The proportion of green materials was higher in the LP hens and highland villages, while the proportion of grains
was higher in the Ri hens and lowland village (p < 0.05). The dry matter, crude protein (CP), ether extract (EE), total ash (Ash), calcium (Ca), phosphorus, and metabolizable
energy (ME) contents were significantly higher for the rainy season (p < 0.01), and CP, Ash, Ca and ME were higher for the LP hens. The crude fibre content was higher in the dry season, and in
the Ri hens and highland village (p < 0.001). The total and essential amino acid concentrations were significantly higher in the rainy season, and in the LP
hens (p < 0.05), but were not different between locations (p > 0.05). Nutrient intakes from scavenging were estimated at between 20% and 30% of requirements. 相似文献
42.
土石坝的安全性一直是备受关注的研究热点。洪水漫顶是影响大坝安全性的重要因素。对水库大坝洪水风险进行准确评估,可为保障水库大坝安全性提供理论依据。该文基于大坝漫顶风险分析理论,建立了漫顶失事模糊风险模型。并以新疆玛纳斯河夹河子水库为例,对其土石坝洪水漫顶模糊风险进行了评估,并得出主要结论:该水库大坝平均漫顶失事模糊风险率为5.02×10-3,超过了我国大坝风险评价标准,该坝的洪水漫顶破坏风险较大。 相似文献
43.
范晓洁 《内蒙古农业大学学报(自然科学版)》2012,33(2):133-135
根据项目的实际情况,经现场查看对内蒙古鄂尔多斯蒙西工业园区供水工程多角度分析研究,得出综合评价结论. 相似文献
44.
45.
Melissa Cordero Dianne McFarlane Melanie A. Breshears Lisa M. Miller Margaret A. Miller Wendy M. Duckett 《Journal of Equine Veterinary Science》2012
The objective of this study was to determine the effect of season on the histologic and histomorphometric appearance of the normal equine pituitary gland. Pituitary glands were collected at necropsy from 121 horses throughout the year. Plasma was also collected from 59 of these horses before euthanasia. Hematoxylin and eosin stained median sagittal sections of each pituitary were evaluated and histologically graded by three pathologists. Histomorphometric analysis was performed on the same slides. Plasma α-melanocyte stimulating hormone was measured by radioimmunoassay in a subset of horses (n = 59). A total of 118 pituitary glands were included in the study after exclusions were made on the basis of the presence of pars intermedia (PI) adenomas (>5 mm). There was a positive correlation between PI hormone concentration (α-melanocyte stimulating hormone) and PI area. Pituitary gland measurements and grades from samples collected in the fall were compared with those collected in the nonfall months using t-test. The PI area, total pituitary area, and PI/total pituitary ratio were significantly greater in the fall compared with nonfall months (P < .0001, P < .01, P < .0001, respectively). Pituitary grades were also higher in the fall compared with nonfall months (P < .001). There was no seasonal difference in pars distalis or pars nervosa area. The results of this study show that the normal equine pituitary shows seasonal changes in appearance and size. These changes must be considered when using postmortem histologic evaluations in the diagnosis of pituitary pars intermedia dysfunction or for validation of antemortem diagnostic tests. 相似文献
46.
《Plant Production Science》2013,16(4):395-400
AbstractWe evaluated the varietal difference in the flood tolerance of germinated seed in 17 Japanese varieties of common buckwheat (Fagopyrum esculentum Moench), including both local varieties and bred varieties or lines of different agroecotypes. Germinated seeds were flooded for 1 day in a growth chamber in June, July and August. The mean rate of seedling emergence from the seeds sown on different dates varied with the variety ranging from 20.4 to 57.4%. The mean emergence rate of summer agroecotypes (29.9%) was significantly lower than that of intermediate and late-summer agroecotypes (42.8 and 40.1%, respectively), and that of local varieties (44.2%) was significantly higher than that of bred varieties or lines (31.2%). These results suggest that inherent variation in flood tolerance was decreased by breeding as a result of a bottleneck effect. The local variety ‘Kitou zairai’, which exhibited a high and stable seedling emergence rate, may be a suitable choice in breeding for flood tolerance during germination. We also attempted to select for flood tolerance under mild selection pressure. Mass selection after four generations increased seedling emergence rate in five of six selected lines (with the exception of ‘Kitawasesoba’) compared with those of unselected populations, although the results varied with the line. These results indicate the possibility of breeding for flood tolerance during the germination period. 相似文献
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48.
利用盐城市1981-2018年逐月降水量和暴雨日数资料,使用一元线性回归法和5年滑动平均法,对盐城市暴雨特征进行分析,并给出了几点防涝减灾措施,以降低暴雨洪涝灾害造成的损失。 相似文献
49.
洪水灾害是我国城市中发生较为频繁且破坏性较大的自然灾害之一,阻碍城市可持续发展。针对已有研究中设定堤防一点漫决堤情景模拟方法较为单一的缺点,提出多点堤防漫决堤洪水演进方法。以哈尔滨市松北区为实证研究区,以水动力学方法为基础,以不规则网格为洪水灾害数值模型骨架,以一、二维非恒定流为洪水灾害数值模型控制方程,综合构建堤防多点同时漫决堤情景下洪水演进模型,并对研究区不同洪水频率情景进行模拟。研究结果表明,该方法可以较好地模拟多点破堤情景下,即0.5%频率、1%频率、2%频率的洪水演进及叠加效果,其中当破堤1 h后研究区最大淹没水深可达3 m以上,同时利用GIS空间可视化技术对研究结果进行可视化表达,为防洪规划设计提供决策依据。 相似文献
50.