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31.
The transgenic expression of Aspergillus xyloglucanase cDNA (AaXEG2) with 35S promoter in the leaves of open field-grown poplars was studied. The level of xyloglucan in the transgenic poplars was decreased to 15–16% in the non-fertile soil (forest-field soil) and to 21–22% in the fertile soil (farming-field soil) compared with that of the wild-type poplars. The leaves exhibited a smaller surface area with more rounded teeth than those of the wild-type plants, similar to the sun leaf variety that was grown in the incubation room and subsequently greenhoused. The majority of total veins with water-conducting vascular bundles were shorter in the leaves of the transgenic poplars than those of the wild type. This decrease in vein length may result from a decrease in xyloglucan during leaf development, from which large numbers of proteins were markedly downregulated in the leaves of the transgenic plants via proteomic analysis. It seems likely that the leaves of the transgenic poplars came to relax the edges of their tooth rather than extend their veins as a result of the loosening of the xyloglucan cellulose networks in the leaves.  相似文献   
32.
Cytotoxic T-lymphocyte (CTL) responses to hemagglutinin (H) protein of canine distemper virus (CDV) were evaluated in dogs using the replication-deficient adenovirus protein expression system. Skin fibroblasts were isolated from two dogs and were infected with recombinant adenovirus bearing the CDV-H gene (Ade-CDVH). CTL assay was performed using fibroblasts expressing CDV-H protein as target cells and peripheral blood lymphocytes (PBL) collected from the same dogs one week after immunization of CDV as effector cells. Specific cytotoxic activity was observed against autologous but not heterologous fibroblasts expressing CDV-H protein. These results indicate that the CTL epitope(s) were localized in the H protein.  相似文献   
33.
The objectives of the present study were to determine the effect of ruminal dosing of mechanical stimulating brush (Rumen faibu; RF) on digestibility and on rumen fermentation status in Holstein steers fed high concentrate and low rice straw. Eight steers (461 kg in average bodyweight) were used. Four steers were orally dosed three RF per head (RF‐dosing) and the other four were not dosed (non‐RF). All steers were fed enough concentrate and rice straw to gain 1.4 kg/day in bodyweight. Rice straw was cut 2 cm and 30 cm. The organic cell wall content of feeding diets was 17% in dry matter basis. Digestibility and nutritive value were not affected by RF dosing and length of rice straw. Ruminal pH was significantly lower in RF‐dosing group than in non‐RF group after feeding, and tended to be higher in long rice straw than in short rice straw throughout the day. There were no clear difference on total volatile fatty acid concentration and molar proportion of volatile fatty acid by RF dosing and length of rice straw throughout examined period. These present results suggest that digestibility and rumen fermentation status are not affected by RF dosing when organic cell wall content of feeding diets is approximately 17% in dry matter with rice straw over 2 cm.  相似文献   
34.
In the present study, 15 canine ovaries without morphological lesions were examined histologically and immunohistochemically by using a large number of proteins including AE1/AE3, cytokeratin7 (CK7), CK13, CK20, vimentin, desmin, alpha smooth muscle actin (alphaSMA), calponin, S100, Neurofilaments, Inhibinalpha, placental alkaline phosphatase (PLAP) and neuron-specific enolase. Ovarian structures observed in this study included surface epithelium (SE), cortical tubules (CT), tunica albuginea (TA), stromal cells (SC), internal endocrine cells (IE), rete ovarii (RO) and fallopian tubes (FT). SE, CT, RO and FT were broadly immunoreactive for desmin. Besides AE1/AE3 and vimentin, desmin was also closely linked to these structures. Rete ovarii forming a reticular structure showed a positive reaction to S100. Surface epithelium was immunoreactive for PLAP at a significantly high level. In conclusion, these results indicate a specific segment of immunoreactivity as well as the broad range of immunoreactivity in canine ovary. The distinct patterns of immunoreactive for various kinds of proteins will play an important role in facilitating their identification and discrimination even in a normal canine ovary with a complex structure.  相似文献   
35.
Chemoreceptor cells aggregating in clusters in the chicken thoracic aorta contain 5-hydroxytryptamine (5-HT) and have voltage-dependent ion channels and nicotinic acetylcholine receptors, which are characteristics typically associated with neurons. The aim of the present study was to investigate the effects of 5-HT uptake inhibitors, fluvoxamine, fluoxetine and clomipramine (CLM), and amphetamine derivatives, p-chloroamphetamine (PCA) and methamphetamine (MET), on endogenous 5-HT outflow from the isolated chick thoracic aorta in vitro. 5-HT was measured by using a HPLC system with electrochemical detection. The amphetamine derivatives and 5-HT uptake inhibitors caused concentration-dependent increases in endogenous 5-HT outflow. PCA was about ten times more effective in eliciting 5-HT outflow than MET. The 5-HT uptake inhibitors examined had similar potency for 5-HT outflow. PCA and CLM increased 5-HT outflow in a temperature-dependent manner. The outflow of 5-HT induced by PCA or 5-HT uptake inhibitors was independent of extracellular Ca2+ concentration. The 5-HT outflow induced by CLM, but not that by PCA, was dependent on the extracellular NaCl concentration. These results suggest that the 5-HT uptake system of 5-HT-containing chemoreceptor cells in the chicken thoracic aorta has characteristics similar to those of 5-HT-containing neurons in the mammalian central nervous system (CNS).  相似文献   
36.
The biological and psychological significance of oxytocin is increasingly recognized; however, reliable assays of oxytocin in biological samples have not been developed. We raised a new oxytocin polyclonal rabbit antibody against synthetic oxytocin. The affinity of antibodies to oxytocin was examined by a radio-immunoassay and compared with that of a previously validated antibody. One antibody showed affinity for oxytocin in the radio-immunoassay. We developed a solid-phase ELISA for oxytocin using this antibody and compared it with existing methods. The newly developed ELISA showed comparable results using urine samples but not using serum samples. These results indicate that the new ELISA is useful for urinary oxytocin; further modifications, such as different extraction methods, are needed for its application to serum oxytocin.  相似文献   
37.
Pyrolysis-gas chromatography in the presence of tetramethylammonium hydroxide (TMAH) was applied to the determination of the ratio of the abundances of the syringyl beta-aryl ether subunits to those of the guaiacyl equivalents (S/G) in lignin. Diazomethane-methylated kenafs (Hibiscus cannabinus and Hibiscus sabdariffa) and beech (Fagus crenata) in situ lignins were employed. Relative abundances of pyrolysis products derived from the guaiacyl and syringyl beta-aryl ether subunits were determined. The S/G ratios for in situ lignins were obtained with average 3.1% relative standard deviation for a minimum of six repeated runs. The S/G ratios determined by pyrolysis in the presence of TMAH agreed well with those determined by thioacidolysis, with a significant linear regression (R(2) = 0.9867). The results showed that pyrolysis with TMAH is an effective tool for obtaining information on the S/G ratio for in situ lignins.  相似文献   
38.
ABSTRACT

After the rice harvest in Japan, rice straw (RS) is usually cut by combine harvester and incorporated into the soil to improve its fertility. In mixed crop–livestock systems, however, RS is collected and used as livestock feed, and cow dung compost (CDC) is then applied to the soil. This system utilizes the residual organic matter from both rice production and livestock husbandry to make each product. CDC application is also considered to improve the fertility of paddy soil. However, the nutrient input from CDC and the effect of CDC application on soil fertility vary among regions and/or soil types. We compared soil fertility between RS application (RS treatment, avg. 32 years) and RS removal plus CDC application (CDC treatment, avg. 21 years) in 79 paddy fields in Mamurogawa town, Yamagata Prefecture, a cold temperate region of Japan, and measured the nutrient contents in the applied RS and CDC. The total C content of RS was significantly higher than that of CDC, whereas the N, P, K, and Si contents of CDC were significantly higher than those of RS. However, there was no significant difference in paddy soil fertility – as measured by soil organic C, total N, CEC, available N, P, and Si, exchangeable K, Ca, and Mg, base saturation percentage, pH, and bulk density – between the treatments. The soil fertility of most fields was adequate by RS or CDC treatment. Thus, leaving RS in paddy fields or removing it and then adding CDC to the paddy fields has a similar effect in maintaining adequate soil fertility for single rice production or rice–livestock production systems.  相似文献   
39.
ABSTRACT:   Using the dorsal ordinary muscle (DOM) of cultured Pacific bluefin tuna (body length [BL]: 47.5–81.8 cm, body weight [BW]: 2.1–13.5 kg, n  = 15), the changes of proximate compositions and myoglobin (Mb) content with growth were investigated. There was a positive correlation ( r  = 0.9832, P  < 0.05) of BL and BW in cultured tuna. The protein contents of the DOM of cultured tuna decreased ( P  < 0.05) and the lipid contents had a tendency to increase (not significantly) with growth. The meat color changed from pink to red with growth. In addition, the Mb contents of the DOM of cultured tuna increased ( P  < 0.05) from 1.0 mg/g (minimum BW fish) to 3.8 mg/g (maximum BW fish) with growth. These results indicate that the increase of the Mb content in the DOM of cultured tuna is not caused by the restriction of exercise and overfeeding between 2.1 kg and 13.5 kg of BW.  相似文献   
40.
Imported genetically modified (GM) canola (Brassica napus) is approved by Japanese law. Some GM canola varieties have been found around importation sites, and there is public concern that these may have any harmful effects on related species such as reduction of wild relatives. Because B. juncea is distributed throughout Japan and is known to be high crossability with B. napus, it is assumed to be a recipient of B. napus. However, there are few reports for introgression of cross-combination in B. juncea × B. napus. To assess crossability, we artificially pollinated B. juncea with B. napus. After harvesting a large number of progeny seeds, we observed false hybrids and metaxenia of seed coats. Seed coat color was classified into four categories and false hybrids were confirmed by morphological characteristics and random amplified polymorphic DNA (RAPD) markers. Furthermore, the occurrence of false hybrids was affected by varietal differences in B. napus, whereas that of metaxenia was related to hybridity. Therefore, we suggest that metaxenia can be used as a marker for hybrid identification in B. juncea L. cv. Kikarashina × B. napus. Our results suggest that hybrid productivity in B. juncea × B. napus should not be evaluated by only seed productivity, crossability ought to be assessed the detection of true hybrids.  相似文献   
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