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131.
We investigated habitat segregation and patterns of species diversity of trees in relation to variations in fluvial and geomorphic disturbances (erosion or sedimentation) along a longitudinal stream gradient from V-shaped valley to alluvial fan and between valley and adjacent hill slopes in a warm-temperate mountainous riparian forest in Kyushu, southwestern Japan. We longitudinally divided the riparian area into four geomorphic zones: V-shaped valley (VV-zone), upper fan (UF-zone), middle fan (MF-zone), and lower fan (LF-zone). We surveyed the distribution of tree species (diameter at breast height ≥3 cm) in the four riparian zones and in additional plots on hill slopes (SL-zone) representing the broader, nonriparian forest matrix. Detrended correspondence analysis ordination demonstrated variations in species composition along the longitudinal stream gradient. Species guild analysis based on the detection of the species preferred zone by a bootstrap method revealed a guild structure corresponding to each geomorphic zone. The four riparian zones were differentiated from the SL-zone by having a low proportion of SL-guild species and a high proportion of infrequent species that were characterized by deciduous leaf habit. The LF-zone was the most differentiated and was characterized by low tree density and specialist species established on the flat and unstable soil surface created by frequent deposition of sediment. The UF- and MF-zones were characterized by a high tree density and species richness (particularly of infrequent species) established on the stable ground surface of a high alluvial terrace. Microsite heterogeneity produced by channel formation may also maintain a high species diversity in the riparian zones.  相似文献   
132.
A simple and rapid analytical method for thiabendazole (TBZ), imazalil (IMA), and o-phenylphenol (OPP) in citrus fruit has been developed by using flow-injection electrospray ionization tandem mass spectrometry for the first time. The method involves the combined use of stable isotopically labeled internal standards (thiabendazole-(13)C(6), imazalil-d(5), and p-phenylphenol-d(9)) and a multiple reaction monitoring technique. The average recoveries for the fungicides at the tolerance levels (TBZ and OPP, 10 mg/kg; IMA, 5 mg/kg) ranged from 77 to 101%, with the coefficients of variation (CVs) ranging from 0.7 to 4.2% (n = 5). At half the tolerance levels (TBZ and OPP, 5 mg/kg; IMA, 2.5 mg/kg), the average recoveries ranged from 62 to 112%, with the CVs ranging from 0.7 to 8.4% (n = 5). The CVs of the average recoveries, obtained from lemon samples fortified with three fungicides at the tolerance levels, obtained on three different days over two weeks, ranged within 2%. The analysis time, including sample preparation and determination, is only 15 min.  相似文献   
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To investigate the predominance of Malassezia pachydermatis (M. pachydermatis) as a causative agent of canine otitis externa, ear cerumen samples were observed for adhesion of M. pachydermatis to the cornified epithelial cells by light and electron microscopes. The yeasts appeared not to adhere to the cornified epithelial cells directly, but they seemed to exist in the proximity of the epithelial cells with an electron opaque halo-like space around them. Polysaccharide and lipid staining techniques were conducted to identify the substances existing in that space. Lipid substances, not saccharides, were observed around the yeasts and the cornified epithelial cells. These results suggested that in the canine ear canal malassezia yeast attachment to the cornified epithelial cells is mediated by lipids.  相似文献   
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Pollenosis is a disease that affects 1 in 10 of the Japanese population. During the season of cedar pollen dispersal, many patients suffer from symptoms such as sniffling, sternutation, and itching of the eyes. Japanese butterbur is a popular vegetable and is one of the few domestic vegetables in Japan. The anti type I allergic effects of an aqueous ethanol extract from aerial parts of Japanese butterbur (JBE) were evaluated in rats and RBL-2H3 mast cells. In the passive cutaneous anaphylaxis reaction in rats, a single oral treatment of JBE (1000 mg/kg) was found to suppress the reaction. In IgE-sensitized RBL-2H3 cells, JBE (10-100 microg/mL) inhibited beta-hexosaminidase release, leukotriene C(4)/D(4)/E(4) synthesis, and TNF-alpha production. Moreover, a high concentration of JBE (1000 microg/mL) suppressed smooth muscle constriction induced by histamine (10 microM) and leukotriene D(4) (10 nM) in a guinea pig trachea strip. The search for components in JBE with an inhibitory activity on mast cell degranulation was guided by inhibition of beta-hexsosaminidase release. Two eremophilane-type sesquiterpenes, six polyphenolic compounds, and two triterpene glycosides were isolated. Of these compounds, fukinolic acid, a principal polyphenol constituent, showed potent inhibitory activity (IC(50) value = 2.1 microg/mL). Consequently, On the basis of its inhibition of mast cell activation and direct smooth muscle reaction induced by released mediators, JBE was found to suppress the type I allergic reaction.  相似文献   
138.
Six Eurasian red squirrels (Sciurus vulgaris orientis), victims of road traffic found during 2002 and 2004 near the Noppro Forest Park in Ebetsu, Hokkaido, Japan, were examined for the presence of Babesia parasites. Three of the six squirrels exhibited positive signals by nested PCRs targeting both the 18S rRNA and beta-tubulin genes. Three squirrels proved to be infected with a B. microti-like parasite as evidenced by sequencing the amplified DNAs and by the morphology of the intraerythrocytic parasites. Genotypically, however, the parasite appeared to be of a new type, as it was clearly distinguishable from any of the known types that have previously been reported in various wild animals. This is the first report showing molecular evidence for the presence of B. microti-like parasites in Sciuridae.  相似文献   
139.
The objective was to investigate the impact of nutrient intake during the early growth period on the expression of glucose metabolism‐related genes in skeletal muscle of cross‐bred cattle. From 1.5 to 5 months of age, group H (n = 7) animals were intensively fed a high‐protein and low‐fat milk replacer [crude protein (CP) 28%; ether extracts (EE) 18%; max: 2.0 kg, 12 l/day], and group R (n = 7) animals were fed a restricted amount of normal milk replacer (CP 25%; EE 23%; max 0.5 kg, 4 l/day). From 6 to 10 months of age, group H cattle were fed a high‐nutrition total mixed ration mainly prepared from grain feed, and group R cattle were fed only roughage. Blood samples were taken from each animal at three biopsy times (1.5, 5 and 10 months of age), and the blood plasma concentration of glucose and insulin was analysed. In glucose concentration, there were no significant differences; however, the concentrations of insulin were higher in group H than in group R at 5 and 10 months of age. Muscle samples were taken by biopsy from longissimus thoracis muscle (LT) at 1.5, 5 and 10 months of age. We analysed mRNA expression levels using the quantitative real‐time polymerase chain reaction (PCR) assay for glucose transporters (GLUT1 and GLUT4), insulin receptor, phosphatidylinositol 3‐kinase (PI‐3K), protein kinase B (PKB, also known as Akt), hexokinase 1 (HK1) and tumour necrosis factor alpha (TNFα). Although no differences were detected at 1.5 and 5 months of age, at 10 months of age, GLUT1, HK1 and TNFα mRNA expression levels were significantly higher in group H than in group R. These results suggested Glut1 that affects insulin‐independently mediated glucose uptake was more responsive to improved nutrition during early growth stage than GLUT4 that insulin‐dependently mediated glucose uptake in LT of cattle.  相似文献   
140.
This study was conducted to examine uterine changes and uterocervical discharges following intrauterine infusion with liquid paraffin (LP) during the luteal phase by ultrasonic and vaginoscopic examinations in cows. Multiparous dairy cows (n=10) were infused with 50 ml physiological saline (PS group; n=5) or liquid paraffin (LP group; n=5) on day 10 or 11 after ovulation (day 0: ovulation). Vaginoscopic, rectal and ultrasonogaphic examinations were carried out at 0.25, 1, 2, 3, 4, 6, 8, 12 and 24 h after the LP and PS infusion and then at daily intervals until subsequent ovulation after the infusions. The mean volumes of recovered discharges from the vagina within 6 h after infusion were significantly greater (P<0.05) in the LP group than in the PS group (33.0 +/- 9.9 vs.14.0 +/- 13.9 ml). Yellowish-white discharge was first observed at 3.2 +/- 0.5 and 3.6 +/- 0.6 h after infusion and lasted for 12.2 +/- 2.9 and 2.1 +/- 1.5 days for the LP and PS groups, respectively, showing a significant difference (P<0.05) in duration. Subsequently, transparent discharge appeared again 2-3 days before the subsequent ovulation after the treatments in both groups and disappeared on the day prior to or the day of ovulation. During the immediate examination after the infusion, the cavity of the uterine horn appeared anechoic and dilated in the images of both groups. The anechoic images changed to echoic images at 2.2 +/- 0.8 and 2.6 +/- 0.9 h after the infusion in the LP and PS groups, respectively, and the echoic images lasted for 12.2 +/- 2.9 and 2.1 +/- 1.5 days in the LP and PS groups, respectively. These results suggest that the appearance and disappearance of intrauterine anechoic and echoic images reflect the appearance and disappearance of the characteristics of the recovered LP/PS-like liquid and yellowish-white and transparent discharges from the vagina.  相似文献   
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