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1.
The seasonal change in petal color and pigmentation of 29 commercial Eustoma cultivars was studied. The flowers are basically divided into four groups according to the major anthocyanidin phenotype in association with petal coloration, i.e., delphinidin (Dp)-based (purple flower), cyanidin (Cy)-based (reddish purple flower), pelargonidin (Pg)-based (pink flower), and none (white flower) groups. The constitution of petal anthocyanidins was not changed by forcing treatment in most of the flowers. Lightness (L*) and chroma (C*, color saturation) showed a change along with the increase/decrease of hue angle difference (ΔH*), thus simultaneously the chromatic tonalities tended to move to redder and bluer, respectively. Floral pigment clustering described two flower groups in a dendrogram, based on anthocyanidin constitutions as phenetic markers, which are apparently the Dp- and Pg-based phenotypes of anthocyanidin syntheses. The Cy-based flowers made a subcluster with the Pg-based flowers, indicating a close relationship in the biosynthesis of the two anthocyanidins, and suggesting the Dp- and Pg-syntheses complement one another.  相似文献   
2.
A questionnaire study examining Japanese consumers’ requirements for beef quality was carried out in April 2002 in Tsukuba, Ibaraki, Japan. Answers from 532 participants were used for the statistical analysis. Twenty questions about sensory properties, appearance, safety and freshness, production area, price, and other properties were prepared. The answers were applied to principal component analysis. Five principal components were obtained and defined, and the principle component scores were used to classify participants. The panels were classified into four groups profiled as ‘specific quality orientated’, ‘Wagyu (Japanese beef) orientated’, ‘safety and freshness orientated’ and ‘overall high quality orientated’. In addition, gender and age characteristics were different among the groups. Sensory properties did not affect the classification of respondents.  相似文献   
3.
The effect of insulin on the ascorbate recycling system in the chicken liver was examined. First, insulin was injected subcutaneously into the chicken, and liver glutathione‐dependent dehydroascorbate reductase (GSH‐DHAR) activity was determined. Insulin increased liver GSH‐DHAR activity, but did not affect plasma and liver ascorbate concentration. Dehydroascorbate increased plasma and liver ascorbate levels, and liver GSH‐DHAR activity. However, distinct changes in plasma insulin level were not observed by dehydroascorbate injection. In addition, reduction of external dehydroascorbate in cultured chicken hepatocytes could not be observed in an insulin‐deprived culture, although the cells reduced external dehydroascorbate in a serum‐free culture with insulin. We concluded that insulin affects the ascorbate recycling system as an essential factor in the chicken liver.  相似文献   
4.
We examined the antimicrobial susceptibility of 848 Escherichia coli isolates from 237 feces samples of wild sika deer (Cervus nippon) captured between 2016 and 2019 in 39 of the 47 prefectures of Japan. Five of the 237 wild sika deer (2.1%) carried E. coli with resistance to at least one antimicrobial, and all the resistant isolates showed resistance to tetracycline. The resistant isolates contained antimicrobial resistance genes that were similar to those in E. coli derived from humans and farm animals. Although wild sika deer are not currently likely to be a source for the transmission of antimicrobial resistance in Japan, they can potentially mediate antimicrobial resistance spread by coming into contact with humans, animals, and their surroundings.  相似文献   
5.
MX belongs to a family of type I interferon (IFN)-stimulated genes, and the MX protein has antiviral activity. MX has at least two isoforms, known as MX1 and MX2, in mammals. Moreover, bovine MX1 has been found to have alternative splice variants—namely, MX1-a and MX1B. In ruminants, IFN-τ—a type I IFN—is temporarily produced from the conceptus before implantation and induces MX expression in the endometrium. However, the expression dynamics of MX after implantation are not clear. In the present study, we investigated the expression of MX1-a, MX1B and MX2 in the endometrium and placenta before and after implantation along with the expression of IFN-α, type I receptors (IFNAR1 and IFNAR2) and interferon regulatory factors (IRF3 and IRF9). Pregnant uterine samples were divided into five groups according to pregnancy days 14–18, 25–40, 50–70, 80–100, and 130–150. Tissue samples were collected from the intercaruncular endometrium (IC), caruncular endometrium (C) and fetal placenta (P). Although all the MX expressions were significantly higher in the IC and C at days 14–18, presumably caused by embryo-secreted IFN-τ stimulation, their expressions were also detectable in the IC, C and P after implantation. Furthermore, IFN-α expression was significantly higher in the IC. RT-PCR indicated IFNAR1, IFNAR2, IRF3 and IRF9 mRNA in all the tissues during pregnancy. These results suggest that all the MX genes are affected by the type I IFN pathway during pregnancy and are involved in an immune response to protect the mother and fetus.  相似文献   
6.
7.
Perchloric acid-soluble protein (PSP) is a members of a new hypothetical family (YER057c/YJGF family) of small proteins with presently unknown function. The high degree of evolutionary conservation of these proteins reflect an involvement in basic cellular regulation. The expression of PSP was examined in rat hepatoma cell dRLh 84-beared rats. The tumor weight increased to 4.24 g at 3 weeks after the transplantation of hepatoma cells and hepatoma which has less differentiated characteristics were observed in rat liver. The expression of PSP in rat hepatoma was down regulated as compared with intact tissue. Thus the expression of PSP seems to be associated with the differentiation process in these transformed cells. On the other hand, some positive cells against the PSP-antibody were observed in the central region of tumor tissue by immunohistochemistry. These cells were shown to be the lymphocytes and the macrophages. The involvement of PSP to cellular growth and differentiation is discussed.  相似文献   
8.
We investigated the validity and efficiency of a survey using sight per unit effort (SPUE) of sika deer and shrub-layer decline rank (SDR), which is an index of decline in the physical structure of a whole stand caused by sika deer, based on data collected on a broad scale. This survey was to be used to manage a deer population in order to conserve a forest ecosystem. First, we evaluated the spatial and temporal scales of deer density that are most appropriate for predicting decline in the status of understory vegetation. The model with SPUE calculated in a buffer with a radius of 4.5 km using data for the past 4 years was found to be the best. We showed that our knowledge of the relationship between deer density and status of shrub-layer vegetation is improved by identifying the most suitable spatial and temporal scales of SPUE for predicting SDR. Next, we quantified the effects of SPUE and environmental components on SDR in stands. We found that SPUE had the greatest effect on SDR among all explanatory variables. Moreover, the area under the curve (AUC) was large in a model that only used SPUE (AUC = 0.718). This result suggests that the variation in SDR among stands was explained well by SPUE regardless of differences in the forest environment. Furthermore, we identified the effective values of SPUE for preventing shrub-layer vegetation from declining through deer density control. We conclude that a management system based on SPUE and SDR is a simple and valid method for managing deer populations in order to conserve forest ecosystems.  相似文献   
9.
 The amounts of CO2 that are absorbed and emitted by forest in a model stand area were determined using two calculation methods, namely the flow approach and the stock approach for emission trading, to understand the relationships between the cutting age for the highest profit rate (CAHPR; optimum tree ages to be cut so as to maximize the profit) and (1) the prices of CO2 and (2) the balance between CO2 emission and absorption. The resultant CAHPR differed between these two CO2 accounting methods, which give different tree ages for maximum log volume yield. A rise in CO2 price caused the CAHPR to approach the tree age of maximum log volume in the flow approach method, and to deviate from the tree age of maximum log volume in the stock approach method. Even at the same CO2 price, the CAHPR differed between the CO2 accounting methods. At low CO2 prices, the CAHPR did not affect situations where the difference of average profit is large by cutting age. On the other hand, the CAHPR was greatly affected at low CO2 prices when the mean log volume growth changed with tree age. These trends were found to be universal. Received: September 18, 2001 / Accepted: October 25, 2002 Acknowledgments This study is one of the fifth science study subsidy projects of the Japan Forest Technology Association. Correspondence to:K. Sakata  相似文献   
10.
Summary A light microscopic (LM) visual technique to determine the polyethylenimine (PEI) distribution in a wood-PEI composite was studied by the adsorption of acid red or the circulation of Cu(II) ion with PEI in the composite. The amount of the adsorbed dye or Cu(II) on the composite increased linearly with an increase in the PEI content of the wood-PEI. The dyed composites were observed with LM under monochromatic light, corresponding to their absorption maxima at 560 nm for acid red and at 640 nm for copper chelate. The microscopic image was photographically recorded and the negative was subjected to densitometric analysis. At a polymer content lower than 4% in the composite, about 70% of total polymer was located in the middle lamella region, leaving only 30% in the secondary wall. With increasing PEI content of the composite, the concentration in the secondary wall increased, and about 80% of the polymer was located in the secondary wall at a PEI content of 27%. There were no noticeable differences between the amount of polymer detected by dyeing with acid red and by chelating with Cu(II). From the results of the line analysis of the intensity of the characteristic X-ray of uranium, the distribution of the PEI in the cell wall agreed closely with that determined by the LM method. It was concluded that the LM visual technique to determine the PEI location in the wood-PEI composite by dyeing with acid red or by chelating with Cu(II) is a simple and reliable method.  相似文献   
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