全文获取类型
收费全文 | 164篇 |
免费 | 8篇 |
国内免费 | 1篇 |
专业分类
林业 | 9篇 |
农学 | 11篇 |
23篇 | |
综合类 | 16篇 |
农作物 | 28篇 |
水产渔业 | 16篇 |
畜牧兽医 | 61篇 |
园艺 | 3篇 |
植物保护 | 6篇 |
出版年
2023年 | 2篇 |
2022年 | 2篇 |
2021年 | 3篇 |
2020年 | 3篇 |
2019年 | 4篇 |
2018年 | 4篇 |
2017年 | 2篇 |
2016年 | 4篇 |
2015年 | 4篇 |
2014年 | 5篇 |
2013年 | 14篇 |
2012年 | 15篇 |
2011年 | 5篇 |
2010年 | 10篇 |
2009年 | 11篇 |
2008年 | 17篇 |
2007年 | 12篇 |
2006年 | 14篇 |
2005年 | 5篇 |
2004年 | 5篇 |
2003年 | 2篇 |
2002年 | 4篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 5篇 |
1997年 | 2篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 4篇 |
1986年 | 1篇 |
1981年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1974年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有173条查询结果,搜索用时 15 毫秒
121.
Chamroon Maneewan Apichai Mekbungwan Wasin Charerntantanakul Kohsho Yamauchi Koh‐en Yamauchi 《Animal Science Journal》2014,85(5):569-574
To investigate the effects of Centella asiatica (L.) on growth performance, nutrient digestibility and blood composition in piglets, 32 nursery pigs were fed 0.0, 0.5, 1.0 and 2.0% dietary C. asiatica (L.) from 15 to 90 kg BW. At 30 kg BW, nutrient digestibility was measured and at 35 kg BW piglets were vaccinated with Mycoplasma hyopneumoniae. Hematological parameters were checked at 40 and 80 kg BW. Compared with the control, growth performance was not affected. The ether extract, ash and calcium digestibility were lower at 0.5%, and dry matter, crude protein, crude fat, phosphorus and energy digestibility were lower at 1.0% (P < 0.05). On hematological values, at 40 kg hematocrit, total white blood cells, neutrophils, eosinophils, basophils, monocytes and lymphocytes were higher at the 2.0% level (P < 0.05). Most of these values except basophils and monocytes continued until at 80 kg, at which total white blood cells, neutrophils, eosinophils and lymphocytes were higher even at 1.0% (P < 0.05); neutrophil‐to‐lymphocyte ratio tended to be higher at 2.0% (P < 0.03). Cholesterol, triglycerides and antibody levels against M. hyopneumoniae did not differ except that at 40 kg the cholesterol of 0.5% was lower (P < 0.05) and M. hyopneumoniae‐specific antibodies tended to be higher with increasing levels of C. asiatica (L.) (P < 0.07). The result that C. asiatica (L.) could not improve growth performance but increased values of serum hematocrit and white blood cells, and mycoplasma immunity to M. hyopneumoniae might suggest that C. asiatica (L.) has no function to elevate body weight but has the potential to enhance innate immunity. 相似文献
122.
The growth of juvenile abalone in aquaculture is known to be affected by density as a result of competition for food and decreases
in water quality. Our results suggest that behaviour is also affected by density and this also has a significant impact on
the growth of individual abalone. 1800 juveniles of Haliotis rubra were individually tagged and reared for 5 months in 12 gravity-fed tanks at two levels of density. The experimental design
allowed the differentiation of the direct from the indirect effects of density. The abalone growth and distribution was monitored
monthly along with the water quality. The distribution of abalone during daytime was closely related to the availability of
preferred shelter space. The percentage of abalone stacked on the top of others increased with density. Preferred shelter
space was characterized by low light intensity and a corner or edge for the abalone to rest against. Hides at the ends of
the tanks were not occupied as much as others. Abalone were found crawling on the side of the tank during daytime when tanks
were shaded. Abalone juveniles of 15–60 mm showed fidelity to their resting shelter during daytime but this fidelity was significantly
reduced at the higher density. Shading of the tanks totally changed the distribution of the abalone and their daytime behaviour.
Competition for shelter space reduced growth more than water quality.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
123.
Che Ismail Che-Zulkifli Ivan Chong Chu Koh Sufian Mustafa Muhammad Taufik Muhammad Nur Syafaat Adnan Amin-Safwan 《Journal Of Applied Aquaculture》2020,32(3):268-277
ABSTRACT In this study, the cryopreserved spermatozoa of Epinephelus lanceolatus were transported using a novel method involving dry ice as the medium of preservation and a Styrofoam box. Five conditions were investigated for the cryopreserved sperm under different dry ice exposure times of (24, 48, and 72) h corresponding to treatment 1 (T1), 3 (T3), and 5 (T5), respectively. Meanwhile, the remaining treatments (T2 and T4) involved the same exposure to dry ice for (24 and 48) h followed by re-immersion into liquid nitrogen (LN). The performance of the cryopreserved spermatozoa of the hybrid grouper (E. fuscoguttatus ♀ × E. lanceolatus ♂) was evaluated through fertilization and hatching trials. The results showed no significant difference in fertilization for all five treatments. However, significantly poorer hatching rates than the fresh sperm were observed for spermatozoa exposed to dry ice after 48 h. This study recommends the use of the proposed method to successfully transport E. lanceolatus spermatozoa for the production of hybrid groupers via artificial insemination. 相似文献
124.
Navjot S. Sodhi Lian Pin Koh Dewi M. Prawiradilaga Idris Tinulele Tommy Han Tong Tan 《Biological conservation》2005,122(4):547-558
Unprecedented deforestation is currently underway in Southeast Asia. Since this trend is likely to continue, it is critical to determine the value of human-modified habitats (e.g., mixed-rural habitat) for conserving the regional native forest avifauna. The impacts of ongoing deforestation on the highly endemic avifauna (33%) of Sulawesi (Indonesia) are poorly understood. We sampled birds in primary and secondary forests in the Lore Lindu National Park in central Sulawesi, as well as the surrounding plantation and mixed-rural habitats. Species richness, species density and population density of forest birds showed a consistent decreasing trend in the following order: primary forests > secondary forests > mixed-rural habitat > plantations. Although primary forests contained the highest proportion (85%) of a total of 34 forest species recorded from our point count surveys, 40-yr old secondary forests and the mixed-rural habitat showed high conservation potential, containing 82% and 76% of the forest species, respectively. Plantations recorded only 32% of the forest bird species. Fifteen forest species had the highest abundance in primary forests, while two species had higher abundance outside primary forests. Our simulations revealed that all forest birds that were sensitive to native tree cover could be found in areas with at least 20% continuous native tree cover. Our study shows that although primary forests have the highest conservation value for forest avifauna, the potential of degraded habitats, such as secondary forests and the mixed-rural habitat, for conserving forest species can be enhanced with appropriate land use and management decisions. 相似文献
125.
Joni Kujansuu Koh Yasue Takayoshi Koike Anatoly P. Abaimov Takuya Kajimoto Takashi Takeda Morihiko Tokumoto Yojiro Matsuura 《Journal of Wood Science》2007,53(2):87-93
An analysis was performed on the climatic responses of the radial growth of Larix gmelinii (Rupr.) Rupr. on contrasting north-facing and south-facing slopes in Tura, central Siberia. We developed chronologies of
tree-ring width for four plots, designated as north-upper, northlower, south-upper, and south-lower. Both residual and standard
chronologies of tree-ring widths exhibited a significant positive correlation with temperature from the end of May until early
June in all four plots. The chronologies of ring width did not reveal any major difference in the response to temperature
among the four plots. The standard chronologies of ring widths on the north-facing slope were negatively correlated with precipitation
during the winter (October–April) and in early and mid-May, whereas the residual chronologies did not reveal clear relationships
with precipitation during the winter and May. The significant correlation between ring width and temperature from the end
of May until early June indicates that temperatures in springtime play a significant role in the radial growth of L. gmelinii. The negative correlations between standard chronologies of tree-ring width and precipitation in the winter and in May on
the north-facing slope indicate that lowfrequency fluctuations in snowfall have negative effects on the radial growth. However,
these effects vary and depend on the microscale topography.
Part of this report was presented at the 55th Annual Meeting of the Japan Wood Society, March 2005, Kyoto 相似文献
126.
Siew Yoong Lee Kent M. Eskridge Woon Yuen Koh Milford A. Hanna 《Industrial Crops and Products》2009,29(2-3):427-436
The aim of this study was to use a supersaturated split-plot design to identify the significant effects of ten ingredients, each at two levels, and two levels of screw speed on selected properties of starch-based packaging foams. Supersaturated designs are special types of fractional factorial designs that allow for evaluating many factors with a minimal amount of experimental material. Rice starch foams were prepared with a twin-screw extruder. The ingredients used were α-cellulose (fiber), potato starch, poly(lactic acid), polystyrene, glycerol, sodium chloride, talc, sodium bicarbonate, citric acid and moisture content of the feed. The properties studied were radial expansion ratio, unit density, bulk spring index, bulk compressibility and Young's modulus. The results showed that the ingredients identified to have significant effects on the properties were the high levels of talc, citric acid, moisture content and the low level of fiber. Low screw speed was found to have greater effect on the properties of the foams than did the high screw speed. It was concluded that the supersaturated split-plot design was successful in identifying the significant ingredients and screw speed that should be used to further investigate the extrusion of starch-based packaging foams. 相似文献
127.
Koh PO Cho GJ Choi WS 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(10):1019-1022
Estradiol acts as a neuroprotective factor against ischemic brain injury. This study investigated whether estradiol modulates neuroprotective mechanism through the activation of Akt and its downstream target such as Bad in global ischemic injury. Adult female gerbils were ovariectomized and treated with estradiol prior to ischemic injury. Transient cerebral ischemia was accomplished by bilateral clipping of the common carotid artery for 5 min. Brains were collected on 1, 3, 5 day after injury. In hippocampal CA1 region of non-treated gerbils, most of neuronal cells exhibited pyknotic nuclei and showed the positive reaction of TUNEL staining on 5 day after injury. However, estradiol significantly reduced the neuronal cell death. Potential activation was measured by phosphorylation of Akt at Ser473 and Bad at Ser136 using western blot analysis. The levels of pAkt and pBad were significantly decreased in non-treated gerbils on 1-5 day after injury. However, estradiol prevents the global ischemic injury-induced decrease of pAkt and pBad. Our findings suggest that estradiol prevents cell death due to global ischemic injury and that Akt activation and Bad phosphorylation by estradiol mediated these protective effects. 相似文献
128.
Jens Wohlers In-Ock Koh Wolfram Thiemann Wolfgang Rotard 《Water, air, and soil pollution》2009,196(1-4):101-113
Pesticides presently being discharged into the aquatic environment are not only toxic but also only partially biodegradable, they are not easily removed by conventional water treatment plants. Air ionization devices using an atmospheric pressure corona discharge process show great promise in improving degradation of chemical and biological contaminants in water purification plants. In order to assess the effectiveness of this air ionization apparatus, laboratory scale degradation experiments were carried out systematically in a bubble column reactor containing a variety of pesticides such as triazines, carbamates, phenyl urea derivates and chlorophenols relative to the addition of humic acid and inorganic chemicals as well as to pH variation. Chemical oxygen demand (COD) decreased with air ionization treatment and the rate of the biological oxygen demand related to this (BOD/COD) showed improved pesticide biodegradability. Changes in water toxicity were monitored by Daphnia- and Luminescence Bacteria tests. This novel water treatment process is shown to be a potent oxidation technique for persistent organic pollutants such as pesticides. 相似文献
129.
Adaptation of the New Zealand Psa risk model for forecasting kiwifruit bacterial canker in Korea 下载免费PDF全文
Y. J. Koh 《Plant pathology》2018,67(5):1208-1219
Bacterial canker of kiwifruit, caused by Pseudomonas syringae pv. actinidiae (Psa), is a severe threat to kiwifruit production in Korea. An existing infection risk model from New Zealand was adopted to respond to this epidemic. Disease incidence (proportion of diseased leaves on each vine) and weather (hourly temperature, rainfall and relative humidity) data required to develop the model were collected and analysed in the study. Disease incidence data were used to modify and validate the existing model. Because the Psa risk model was originally developed in a region where the characteristic climatic conditions are completely different from those in Korea, the temperature and rainfall functions of the existing model were modified. Analyses using statistical correlation and prediction–realization tables revealed that the modified model is valid with high agreement (a correlation coefficient of 0.85 and an accuracy of 85.7%, respectively) between the observed disease incidence and simulated disease risk from the model. The model was also found to be more highly sensitive to the presence or absence of rainfall than any other weather variable inputs. Uncertainty in simulated disease risk was measured based on the level of uncertainty in temperature input from weather forecasts. Overall, these results indicate that the modified Psa risk model can be used to provide practical and applicable information for timely disease control to the kiwifruit growers in Korea. 相似文献
130.
Sung JH Kim MO Koh PO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(1):35-41
Nicotinamide attenuates neuronal cell death related to focal cerebral ischemic injury. This study investigated whether nicotinamide exerts a neuroprotective effect through the activation of Raf- mitogen-activated protein kinase kinase (MEK)-ERK and its downstream targets, including p90 ribosomal S6 kinase (p90RSK) and Bad. Adult male Sprague-Dawley rats were treated with nicotinamide (500 mg/kg) or vehicle 2 hr after the onset of middle cerebral artery occlusion (MCAO). Brains were collected 24 hr after MCAO. In the present study, nicotinamide significantly reduces the volume of infarct regions and decreases the number of positive cells by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining in the cerebral cortex. Nicotinamide prevents injury-induced decrease in Raf-1, MEK1/2, and ERK1/2 phosphorylation. As part of the downstream cascade, nicotinamide inhibits the injury-induced decrease in p90RSK and Bad phosphorylation. Moreover, nicotinamide prevents the injury-induced increase in cleaved caspase-3 levels. These findings suggest that nicotinamide protects neuronal cells against cerebral ischemic injury and that MEK-ERK-p90RSK cascade activation by nicotinamide contributes to these neuroprotective effects. 相似文献