全文获取类型
收费全文 | 242篇 |
免费 | 7篇 |
专业分类
林业 | 36篇 |
农学 | 9篇 |
23篇 | |
综合类 | 10篇 |
农作物 | 10篇 |
水产渔业 | 31篇 |
畜牧兽医 | 119篇 |
园艺 | 1篇 |
植物保护 | 10篇 |
出版年
2023年 | 1篇 |
2022年 | 7篇 |
2021年 | 9篇 |
2020年 | 3篇 |
2019年 | 2篇 |
2018年 | 1篇 |
2017年 | 6篇 |
2016年 | 9篇 |
2015年 | 4篇 |
2014年 | 10篇 |
2013年 | 8篇 |
2012年 | 12篇 |
2011年 | 19篇 |
2010年 | 2篇 |
2009年 | 8篇 |
2008年 | 12篇 |
2007年 | 13篇 |
2006年 | 17篇 |
2005年 | 27篇 |
2004年 | 15篇 |
2003年 | 16篇 |
2002年 | 8篇 |
2001年 | 6篇 |
2000年 | 7篇 |
1999年 | 6篇 |
1998年 | 2篇 |
1996年 | 2篇 |
1992年 | 3篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1985年 | 2篇 |
1983年 | 3篇 |
1982年 | 1篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1972年 | 1篇 |
排序方式: 共有249条查询结果,搜索用时 62 毫秒
91.
Ikutaro Tsuyama Katsuhiro Nakao Tetsuya Matsui Motoki Higa Masahiro Horikawa Yuji Kominami Nobuyuki Tanaka 《Annals of Forest Science》2011,68(4):689-699
Introduction
The aims of this study were to identify the climatic conditions controlling the distribution of Sasamorpha borealis and to assess the impact of climate change on the species in Japan. 相似文献92.
Feed‐derived volatile basic nitrogen increases reactive oxygen species production of blood leukocytes in lactating dairy cows 下载免费PDF全文
Ei Tsunoda Josef J. Gross Chiho Kawashima Rupert M. Bruckmaier Katsuya Kida Akio Miyamoto 《Animal Science Journal》2017,88(1):125-133
The present study investigated over 9 months the changes of fermentative quality of total mixed rations (TMR) containing grass silage (GS) as a major component, associated with changes in the volatile basic nitrogen (VBN) levels in an experimental dairy farm. Effects of VBN levels in TMR on metabolic parameters, reactive oxygen species (ROS) production by blood polymorphonuclear leukocytes (PMNs) and conception rates for dairy cows were analyzed. According to VBN levels in TMR during survey periods, three distinct phases were identified; phase A with low VBN; phase B with high VBN; and phase C with mid‐VBN. Metabolic parameters in blood were all within normal range. However, during phases B and C, nitrogen metabolic indices such as blood urea nitrogen and milk urea nitrogen showed higher levels compared to those in phase A, and a simultaneous increase in ROS production by blood PMNs and the load on hepatic function in metabolic parameters was observed in the cows with a lower conception rate. This suggests that feeding TMR with elevated VBN levels due to poor fermented GS results in stimulation of ROS production by PMNs by ammonia, and negatively affects metabolism and reproductive performance in lactating dairy cow. 相似文献
93.
94.
The aim of this study was to evaluate the changes in plasma concentrations of estrone sulfate (E(1)S) and estradiol-17beta (E(2)beta) during the peripartum period (from day 10 prepartum to day 1 postpartum) associated with and without retention of fetal membranes (RFM) in Holstein-Friesian cattle (n=42). Plasma samples were analyzed for E(1)S and E(2)beta by ELISA. All parturitions were spontaneous and normal. Of 38 cattle delivering singletons, 29 had no RFM (singleton-normal group) and nine had RFM for more than 12 h (singleton-RFM group). Four cows gave birth to twins, and each twin had its own fetal membrane (FM). Two twinning cows expelled both FMs normally within 12 h (twin-normal group). In the remaining 2 twinning cows (twin-RFM group), the FM was expelled normally for one twin (first), while the FM of the other (second) was retained. There were no significant differences in the E(1)S concentrations or their increments from the concentrations on the preceding day between the normal and RFM groups of singleton cows on any peripartum day. The mean plasma E(2)beta concentrations on each day from day 10 to day 3 prepartum were significantly lower (P<0.05) in the singleton-RFM group compared with the singleton-normal group; however, on days 2 and 1 prepartum, the increments in the E(2)beta concentrations from the concentrations on the preceding days were significantly higher (P<0.05) in the singleton-RFM group than in the singleton-normal group. Thus, the plasma E(1)S concentrations just before parturition may not be associated with RFM. In the cows with RFM, the lower plasma E(2)beta concentrations that were found prior to day 2 prepartum may have been associated with immature placentomes, and the rapid rise in plasma E(2) beta within 1 to 2 days prior to calving may have produced asynchrony of placental and/or fetal maturation in relation to calving, thus resulting in RFM. 相似文献
95.
Genetic Resources and Crop Evolution - To assess the current genetic status of a useful coastal plant Glehnia littoralis F. Schmidt ex Miq. in Japan, the genetic diversity within and among natural... 相似文献
96.
Tanaka T Kassai A Ohmoto M Morito K Kashiwada Y Takaishi Y Urikura M Morishige J Satouchi K Tokumura A 《Journal of agricultural and food chemistry》2012,60(16):4156-4161
Apical application of lysophosphatidic acid (LPA), a growth-factor-like phospholipid, was shown to prevent or restore gastrointestinal (GI) disorders, such as diarrhea and stomach ulcer, in experimental animals. Because LPA is formed from phosphatidic acid (PA) by the activity of digestive phospholipase A(2), PA is a potential component for dietary treatment of such GI disorders. Here, we quantified PA contained in 38 foodstuffs and 3 herbs by a thin-layer-chromatography-imaging technique. Vegetables belonging to Brassicaceae, such as cabbage leaves (700 nmol/g of wet weight) and Japanese radish leaves (570 nmol/g), contained higher amounts of PA than other foodstuffs. Amounts of PA in fruits, cereals, and starchy root vegetables were below 300 nmol/g. Animal foodstuffs contained low amounts of PA (<60 nmol/g). Interestingly, leaves of Mallotus japonicas, a Japanese edible herb used for treatment of stomach ulcer, had the highest PA (1410 nmol/g) among those examined. The data shown here will be useful for the development of dietary treatment for a damaged GI tract. 相似文献
97.
To clarify the optimal water management in large-scale fields under high temperatures at the ripening period, effective water managements during this period for improvement of yield, appearance quality and palatability were investigated. Compared with intermittent irrigation and flooded irrigation, the soil temperature with saturated irrigation remained low throughout the day, and the decrease rate of the bleeding rate of hills was the lowest. These results suggested that the saturated irrigation maintained root activity. For the three irrigation types, the number of spikelets per m2 and 1000-grain weight were similar, however, saturated irrigation resulted in significantly higher rice yield due to improvement in the percentage of ripened grains. The saturated irrigation produced a high percentage of perfect rice grains and thicker brown rice grain, furthermore, the palatability of cooked rice was excellent because protein content and hardness/adhesion ratio were both low. Thus, under high-temperature ripening conditions, soil temperature was lowered and root activity was maintained when applying saturated irrigation after heading time. The results indicated that saturated irrigation is an effective countermeasure against high-temperature ripening damage. 相似文献
98.
Jia Liang Riho Miyazaki Xianxian Zhao Katsuya Hirasaka Shigeto Taniyama Katsuyasu Tachibana 《Fisheries Science》2014,80(5):1083-1088
To elucidate the structural changes in pink (P), white (W), and red (R) muscles during storage in ice, we measured the breaking strength and changes in pericellular connective tissues of cultured carp. The breaking strength just after killing was highest in R muscle (1.00 ± 0.20 N), lowest in W muscle (0.37 ± 0.07 N), and intermediate (0.84 ± 0.12 N) in P muscle. During the storage period, the breaking strength decreased first in R muscle, then in P muscle, followed by W muscle. The diameter of muscle fibers was greater in W muscle (113 ± 15 μm) than in P muscle (72 ± 3 μm) and R muscle (48 ± 2 μm). Destruction of the honeycomb structure of the pericellular connective tissue occurred most rapidly in W muscle and most slowly in R muscle. These results suggest that the interposing of P muscle fibers in the dorsal ordinary muscle contributes to the acceleration of post-mortem tenderization in fish. 相似文献
99.
Chifumi Nagai Jean-Jacques Rakotomalala Riko Katahira Yeyun Li Katsuya Yamagata Hiroshi Ashihara 《Euphytica》2008,164(1):133-142
The GCAs are new tetraploid interspecific hybrids developed in Madagascar from Coffea eugenioides, C. canephora and C. arabica. Selected GCA having genotype UF1023 contained 0.37% DW caffeine and no detectable theobromine in green beans. Low caffeine
accumulation in GCA plants is due mainly to the low biosynthetic activity of purine alkaloids, possibly the extremely weak
N-methyltransferase reactions in caffeine biosynthesis. No significant catabolic activity of caffeine was found in GCA-UF1023,
in common with almost all coffee plants including C. arabica. 相似文献
100.
Serpentinitic soils contain high concentrations of geogenic Ni. During serpentinitic mineral weathering, the Ni released from soils into ecosystems could be a source of non-anthropogenic metal contamination. In this study, soil samples were collected from two pedons in paddy fields in Taiwan and Japan; these samples were used to explore the profile distribution of total and labile Ni, demonstrating the contribution of Ni-bearing Fe and Mn oxides to the Ni partition in these soils. Serpentine and chlorite were the dominant primary minerals; thus, the soils reflected serpentinitic characteristics and exhibited high background concentrations of Ni. The total Ni content ranged from 240 to 520 mg kg?1. Repeated redox and leaching cycles caused the redistribution of Ni in the paddy soils. The diethylenetriamine pentaacetate (DTPA)-extractable Ni, an availability index of Ni, increased as the soil depth decreased in the two pedons. An additional pool of labile Ni was present in the soils because the Ni concentration determined using a 0.1 N HCl extraction was much higher than was that determined using the DTPA extraction. Fe and Mn oxides were closely related to the labile Ni in these paddy soils. However, Ni was predominantly retained by amorphous and crystalline Fe oxides rather than Mn oxides. Shortening the flooded duration of paddy field is required to reduce the solubility of Ni because that the labile Ni and redox-sensitive Fe oxides can affect both the paddy soils and environment when Ni is released into the soil solution and becomes bioavailable under reducing conditions. 相似文献