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1.
We examined the effects of oral administration of L-citrulline (L-Cit) on plasma metabolic hormones and biochemical profile in broilers. Food intake, water intake, and body temperature were also analyzed. After dual oral administration (20 mmol/head/administration) of L-Cit, broilers were exposed to a high ambient temperature (HT; 30 ± 1°C) chamber for 120 min. Oral administration of L-Cit reduced (p < .001) rectal temperature in broilers. Food intake was increased (p < .05) by heat stress, but it was reduced (p < .05) by L-Cit. Plasma levels of 3,5,3′-triiodothyronine, which initially increased (p < .0001) due to heat stress, were reduced (p < .01) by oral administration of L-Cit. Plasma insulin levels were increased by heat exposure (p < .01) and oral L-Cit (p < .05). Heat stress caused a decline (p < .05) in plasma thyroxine. Plasma lactic acid (p < .05) and non-esterified fatty acids (p < .01) were increased in L-Cit-treated heat-exposed broilers. In conclusion, our results suggest that oral L-Cit can modulate plasma concentrations of major metabolic hormones and reduces food intake in broilers.  相似文献   
2.
Japanese farmers manage their irrigation water based on their past experiences and preferences, considering such factors as weather and available water (hereafter defined as empirical water management). They elaborately control the intake and drainage rates of their own paddy fields to maintain optimal ponding depths. But these well-managed systems will drastically change because of the decreasing number of farmers. Therefore, it is necessary to clarify if the optimal ponding depth will be maintained within the limits of traditionally-allowed water intake rate from the main river. The first objective of this study was the quantification of actual water use in the paddy fields, resulting from the farmers water management on the basis of their experience. The significance of the present water intake rate under empirical water management was studied for a paddy field command area of about 230 ha. Water intake rates and the water requirements of the whole area were investigated by measuring the flow rate at 17 points of irrigation and drainage canals. Characteristics of the farmers empirical water management were investigated by measuring the hourly changes in inflow and outflow rates for a sub-area using an automatic measurement system, and an inferential method of determining water management patterns for the paddy fields was proposed. The newly-proposed inferential method was introduced in the tank model, which expresses the characteristics of water management in the command area. The Shuffled Complex Evolution Algorithm (SCE-UA) method was used for optimizing the model parameters. It was proven that the model accuracy improved when the farmers empirical water management was taken into account. The optimal amount of water to be applied to the command area was quantified by the simulation. The second objective was to predict the effect of the decreasing number of farmers on future water use conditions. The simulated result indicates the difficulty of maintaining optimal ponding depth for the whole command area when the farmers empirical water management is not maintained. In other words, results indicated that efficient water use requires an automatic water management system or a new pipeline system to replace the farmers present empirical water management.  相似文献   
3.
The effects of 0.5%, 0.3% and 0.1% w/w concentrations of Senna occidentalis (So) seed mixed with commercial ration were studied in 18 groups of 32 broiler chicks each, from 1 day to 49 days of age. Three groups were fed one of the rations throughout their lives (TL). Three other groups were fed one of the rations from the 1st to the 28th day of life (starter phase, SP), and the final 3 groups were fed one of the rations from the 29th to 49th day (finisher phase, FP). Each experimental group was matched by a control group fed the same diet over the same period but without the inclusion of So. All the animals were killed at 49 days of age, and blood was collected from 10 birds in each group for biochemical studies (ALT, AST, GGT, LDH, UA). A complete necropsy was performed on 3 birds from each group. No significant differences in the biochemical parameters in the serum were found between the control and experimental chicks, but animals treated with 0.5% So in groups FP and TL, gained less weight and chicks that received 0.3% So or 0.5% So in the ration throughout life (TL) had a larger feed conversion ratio. Besides this, degenerative changes were found in the striated skeletal muscle in the chest, in the myocardium and in the liver in the animals that received the higher concentrations of So seeds.  相似文献   
4.
A total of 80 free-roaming dogs on Okinawa Island, Japan, were examined for Babesia infection using the polymerase chain reaction (PCR) and sequence analysis. Of 80 samples, 12 were positive in a Babesia genus-specific PCR. Consequent species-specific PCR for B. canis and B. gibsoni revealed that 5 (6.3%) and 7 (8.8%) dogs were infected with B. canis and B. gibsoni, respectively. Sequence analysis of the PCR products revealed that the 18S rRNA gene sequence of B. canis detected from dogs in Okinawa was very close to B. canis vogeli with sequence similarity of 99.94%.  相似文献   
5.
6.
Autologous bone marrow stromal cells (BMSCs) infusion therapy improves the hepatic fibrosis. To investigate the mechanism of remission, we evaluated the matrix metalloproteinase (MMP)-2 and -9 activity in canine BMSCs and the effect of pro-inflammatory cytokines on their expression. The activity and the gene expression of MMPs were analyzed by gelatin zymography and quantitative RT-PCR, respectively. The specific gelatinase bands were indicative effect of MMP-2 and -9 in canine BMSCs. MMP-2 expression seemed to be increased by TNF-α and IL-1β while MMP-9 was enhanced by TNF-α and IL-6. These results suggested that remissive effect on liver fibrosis might be partly attributable to the MMP-2 and -9 activity in BMSCs under the inflammatory condition.  相似文献   
7.
Oncolytic virotherapy is a novel treatment involving replication‐competent virus in the elimination of cancer. We have previously reported the oncolytic effects of reovirus in various canine cancer cell lines. This study aims to establish the safety profile of reovirus in dogs with spontaneously occurring tumours and to determine a recommended dosing regimen. Nineteen dogs with various tumours, mostly of advanced stages, were treated with reovirus, ranging from 1.0 × 108 to 5.0 × 109 TCID50 given as intratumour injection (IT) or intravenous infusion (IV) daily for up to 5 consecutive days in 1 or multiple treatment cycles. Adverse events (AEs) were graded according to the Veterinary Cooperative Oncology Group‐ Common Terminology Criteria for Adverse Events (VCOG‐CTCAE) v1.1 guidelines. Viral shedding, neutralizing anti‐reovirus antibody (NARA) production and immunohistochemical (IHC) detection of reovirus protein in the tumours were also assessed. AE was not observed in most dogs and events were limited to Grade I or II fever, vomiting, diarrhoea and inflammation of the injected tumour. No infectious virus was shed and all dogs had elevated NARA levels post‐treatment. Although IHC results were only available in 6 dogs, 4 were detected positive for reovirus protein. In conclusion, reovirus is well‐tolerated and can be given safely to tumour‐bearing dogs according to the dosing regimen used in this study without significant concerns of viral shedding. Reovirus is also potentially effective in various types of canine tumours.  相似文献   
8.
Forest development in temperate regions is considered to be a global carbon sink. Many studies have examined forest development after harvesting or fire from aboveground (e.g., biomass) or belowground (e.g., soil nutrient) perspectives. However, few studies have explored forest development from both perspectives simultaneously in cool-temperate forests in Japan. In this study, we examined changes over 105 years in both aboveground and belowground components during secondary natural succession. The aboveground biomass increased for 50 years and reached a plateau in a 105-year-old stand. The N mineralization rate increased during succession for 50 years, but showed a decline in the 105-year-old stand due to the decrease in the nitrification rate in late succession. The percent nitrification (i.e., relative contribution of nitrification to N mineralization) decreased significantly with increasing forest stand age. The N mineralization rates had significant relationships with N concentrations of the dominant tree foliage and litter fall and with the amount of litter fall N. Meanwhile, other belowground properties (i.e., soil pH, phenol concentration, soil microbial respiration, and litter mass loss) did not show any significant relationship with forest stand age. This may be because the soil at the study sites was heterogeneous and consisted of Cambisols and Andosols, the latter of which originally has high organic matter content, and thus may have buffered the effect of the aboveground development. These results indicate that belowground N dynamics are more closely associated with aboveground development than other belowground properties in these forests.  相似文献   
9.
日本北海道东部有两块发展成熟的湿地森林,分别是具有氮固定作用的日本桤木(Alnusjaponica Steud)组成的阔叶林和库页云杉(Piceaglehnii Masters)构成的针叶林,而且两块林地间具有突变的边界。为了阐明突变边界的维持机制,本文研究了森林剖面、水位、地下水、降雨化学、与微环境有关的幼苗建成格局及种子迁移。研究表明,地下水位剖面并不能充分地解释突转临界的形成,但是,两种林地的地下水化学成分存在显著差异,具体表现为库页云杉林地下水中EC,Na^+,心,Mg^2+,Ca^2+和Cl^-含量明显要高于日本桤木林的,而地下水pH值又较低。库页云杉林降雨中富含Na^+,Ca^2+和Cl^-,表明降雨是导致两种林分土壤表层水化学成分差异的主要原因。六月末,库页云杉林的太阳辐射少于2.2MJ&#183;m^-2.d^-1;而日本桤木林太阳辐射强度为1.0—3.7MJ&#183;m^-2.d^-1。土壤表层苔藓主要是泥炭藓,在库页云杉林内覆盖率为60%,而日本桤木林的仅为10%:这一差异与土壤表层水pH值有关。有70%株高在1.3米以下的库页云杉苗木建立在苔藓层上。播种造林实验表明,在库页云杉林2个树种的种子萌发率和幼苗存活率都较高。因此,库页云杉在日本桤木林内繁殖能力较弱,主要是缺少适宜的微环境和较低的苗木建成能力。日本桤木仅靠再萌发繁殖,在两种林分内幼苗较少;此外,日本桤木种子向库页云杉林内的迁移也受到较大的限制,加之库页云杉林内太阳辐射强度较低,导致日本桤木幼苗存活率较低。基于以上结果,我们认为日本桤木与库页云杉形成了各自特有的生长环境,而对彼此的生长环境不适应,抑制了自身种苗向对方林分的扩张和自然再造过程。图9表1参32。  相似文献   
10.
A survey was made of seasonal changes in pH and electronic conductivity (EC) of precipitation inAlnus japonica (Thunb.) Steud. forest in Kiritapp mire, Hokkaido, Japan. The average pH of throughfall and stem flow was higher than that of bulk deposition. When the pH of bulk deposition exceeded 5.5, however, pH of throughfall and stem flow was lower than that of bulk deposition. The EC of stem flow was always higher than throughfall, and that of throughfall higher than that of bulk deposition. The EC of stem flow was highest during the first defoliation period ofA. japonica. On the other hand, the differences in the EC of throughfall and bulk deposition was very few just after the first defoliation period ofA. japonica. This implies that the chemical properties of throughfall and stem flow are strongly affected by the phenology of the plants.  相似文献   
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