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121.
Excessive proliferation of mesangial cells is observed in various types of glomerular disease including glomerulonephritis (GN), which is progressive in nature and eventually results in end-stage renal disease (ESRD). Vitamin K(1) 2,3-epoxide reductase (VKOR) and the vitamin K-dependent growth arrest-specific gene 6/Axl pathway play a key role in mesangial cell proliferation in GN. In the present study, we indicate the potential of a VKOR inhibitor, 3-acetyl-5-methyltetronic acid (AMT), to prevent the proliferation of glomerular mesangial cells and suppress the progression of GN. AMT was administered intravenously to rats once daily for 12 days and a mouse anti-Thy1 monoclonal antibody was injected intravenously after the AMT treatment on Day 6. Creatinine clearance (CCr) significantly increased and the albumin-to-creatinine ratio (ACR) significantly decreased in the AMT-treated group of the Thy-1 GN rats. In addition, glomerular and tubular damage was improved histopathologically in the AMT-treated group. AMT did not affect blood coagulation due to its unique pharmacokinetic properties. The concentration of AMT reached the IC(50) for VKOR in kidney, but not in liver. A novel VKOR inhibitor, AMT, reduced renal mesangial cell proliferation and could be a supportive treatment for GN.  相似文献   
122.
Anti-Müllerian hormone (AMH) and testosterone (T) profiles in blood were investigated before and after an hCG stimulation test to assess their sensitivity and specificity for the existence of a functional cryptorchid testis in Japanese Black calves. The hCG (3,000 IU) was administered on Day 0, and peripheral blood was collected on Days 0 (just before hCG injection), 5 and 7 in intact male calves (Intact; n=19), bilateral castrated calves (Castrated; n=17), unilateral cryptorchid calves, which abdominal testis could been extracted (Uni-crypto; n=9). Castration of a descended testis was carried in the Castrated and Uni-Crypto groups on Day -14. The AMH detectability and the optimum cut-off point for T levels using the receiver operating characteristic curve were verified to characterize the cryptorchid testis. AMH values on Day 0 were 21.1 ± 5.1 and 29.0 ± 7.5 ng/ml in the Intact and Uni-crypto groups, respectively (Mean ± SEM). AMH levels were under the detection limit in the Castrated group (i.e., < 0.006 ng/ml). T showed its peak levels on Day 5 in the Intact group (26.8 ± 4.2 ng/ml), while it remained low in the Castrated group (< 0.9 ng/ml) and did not show a significant difference in the Uni-crypto group. The detectable levels for AMH was 0.006 ng/ml, and the optimum cut-off point for T was 0.9 ng/ml; the sensitivity and specificity for evaluation of testicular descent into the scrotum were 1.0 for both the AMH and T levels. The detection rates in the Uni-crypto group using them were 1.0 and 0.57 for AMH on Day 0 and T on Days 5 or 7, respectively. In conclusion, plasma AMH profiles could be used as a novel biomarker to evaluate the existence of a functional cryptorchid testis in Japanese Black calves.  相似文献   
123.
The species of the genus Actinobacillus have so far been associated with specific animal hosts, and A. suis sensu stricto, an opportunistic pathogen of swine, is rarely isolated from ruminants. We describe here the isolation of A. suis sensu stricto from a newborn calf that died on a dairy farm in Japan. Identification of the isolate was performed by phenotypic and genotypic characterization, with the latter consisting of nucleotide sequence analyses of the 16S rRNA gene plus three housekeeping genes, rpoB, infB and recN.  相似文献   
124.
Vitamin C content in the fruit of various cultivars of kiwifruit and other Actinidia species was estimated by determination of L-ascorbic acid and L-dehydroascorbic acid using ion-pair reversed-phase high-performance liquid chromatography. Fruit of A. deliciosa cv. Hayward, the most common commercially available cultivar, contained 65.5 mg/100 g fresh weight (FW) vitamin C. Vitamin C content in A. deliciosa fruit varied from 29 mg/100 g FW to 80 mg/100 g FW. In most cultivars of A. chinensis, vitamin C content in fruit was higher than that of Hayward. In particular, vitamin C content in cv. Sanuki Gold fruit reached more than 3-fold that of Hayward on a weight for weight basis. In A. argutafruit, there was wide variation in vitamin C content, with concentrations ranging from 37 to 185 mg/100 g FW. In cv. Gassan, Issai, and Mitsuko, vitamin C content of the fruit was much higher than that of Hayward. In A. arguta fruit, the ratio of L-ascorbic acid to total ascorbic acid tended to be higher than that of other species.  相似文献   
125.
Spatial and temporal variation in copepod community structure, abundance, distribution and biodiversity were examined in the western subarctic North Pacific (40–53°N, 144–173°E) during 2001–2013. Continuous Plankton Recorder (CPR) observational data during the summer season (June and July) were analyzed. The latitudinal distribution of warm‐water species in June shifted northward after 2011 while no apparent latitudinal shift of cold‐water and other species was observed. Species number and the Shannon–Wiener biodiversity index (H′) in June tended to increase in the northern area after 2011. The warm‐water species abundance and center latitude of warm‐water distribution were positively correlated with sea surface temperature (SST) across sampling locations, whereas no significant correlations with SST were observed for cold‐water species or other species. Warm SSTs in June after 2011 appeared to cause the northward shift of warm‐water species distribution, which in turn contributed to the higher biodiversity in the northern area. This study demonstrated the rapid response of warm‐water species to warm SST variation, whereas cold‐water and other species did not exhibit such clear responses. These findings indicate that the response of copepods to environmental changes differs among copepod species, highlighting the importance of investigating lower trophic levels to the species level to evaluate individual species’ responses to climate change.  相似文献   
126.
Heat-induced gelation of a cold-water insoluble polysaccharide, Curdlan, was investigated using atomic force microscopy (AFM). Curdlan dissolved into NaOH aqueous solutions exhibited a spectral transition around 0.2 mol/L NaOH, which is an indicative of conformational transitions from a single helix at a lower alkali concentration to a disordered chain at a higher concentration. Nevertheless, AFM images of Curdlan solubilized in 0.01 mol/L NaOH revealed the presence of heterogeneous supramolecular assemblies of Curdlan: the majority of the molecules were in the form of microfibrils, the lengths of which were on the order of micrometers and the cross-sectional heights of which were approximately 2-3 nm, whereas single molecular chains, partially dissociated from these microfibrils, were also observed. Heating such a sol resulted in the formation of densely cross-linked microgel networks. Heat-induced gelation of Curdlan appears to be initiated by partial dissociation of single chains from supramolecular microfibrils and followed by cross-linking of microfibrils via hydrophobic interactions among these partially dissociated chains.  相似文献   
127.
The preferential development of Brassica lateral roots for phosphorus (P) to forage for P fertilizer was observed by using alginate gel beads in which powdery dicalcium phosphate dihydrate (DCPD) was suspended (DCPD gel bead). The DCPD gel beads enabled to detect the characteristic root growth around them because of their larger diameter (1.5 cm) than that of standard fertilizer particles. The thin Brassica lateral roots completely encircled the DCPD gel beads and no soil area remained between the roots and the DCPD gel beads. This morphological plasticity of Brassica roots is highly suitable for improving the P recovery rate because even a few mm of soil with a high P retention capacity between a plant root and P fertilizer reduces the P recovery rate. The P recovery rate in the Brassica shoots exceeded 0.05 and the ratio of the shoot dry weight in the plot treated with DCPD gel beads to that in the control plot exceeded 10. Thus, the Brassica plants showed both a high P recovery rate and satisfactory growth in the P-deficient soil compared with other tested plants due to the complete contact between their roots and the DCPD gel beads. The preferential root proliferation for P was also observed in Fagopyrum esculentum Moench as well as Brassica plants among the 20 tested plants.  相似文献   
128.
This study investigated responsiveness of beef cattle to various environmental stimuli by subjecting 15–16 Japanese Black cows to five tests repeated twice. Within individual behavioral measures, cows were moderately (repeatability = 0.54–0.70) or highly (repeatability = 0.74–0.89) consistent in flight distance during grazing and resting in the human approach tests, maximum distance from the group pen and the number of total and different feed tub visits in the feeding–sociability trade‐off test, and unwillingness to enter the restraint, movement under restraint and flight speed after release from restraint in the social isolation and restraint test. By contrast, cows were not consistent in the latency to make the first contact and the number of contacts with novel object(s) in the novelty test (repeatability = 0.24–0.39). Across behavioral measures in different tests, cows showed no consistency (P ≥ 0.05) in any combinations of measures from the two human approach tests, the trade‐off test and the social isolation and restraint test. In conclusion, human approach (particularly during resting), feeding–sociability trade‐off and social isolation and restraint situations can be used for evaluating personality in Japanese Black cows, while the value of the novelty test needs to be reexamined.  相似文献   
129.
130.
Right ventricular (RV) Tei index (index of myocardial performance) has been demonstrated to be clinically useful in estimating RV function in various human cardiac diseases. The purposes of this study were to validate the correlation between RV Tei index and RV function obtained by cardiac catheterization in healthy dogs, and to evaluate the RV Tei index in dogs with tricuspid regurgitation (TR). In healthy dogs, the RV Tei index significantly correlated with the RV peak +dP/dt (r=-0.80, p<0.0001) and -dP/dt (r=0.69, p=0.0001). In normal dogs, the RV Tei index was not significantly correlated with heart rate, body weight, and age. The RV Tei index significantly increased in dogs with moderate to severe TR (0.39 +/- 0.35, p=0.0015), filariasis (0.46 +/- 0.16, p=0.0131), and trivial to mild TR and severe mitral regurgitation (MR; 0.61 +/- 0.14, p=0.0017) when compared with the normal dogs (0.17 +/- 0.10). In addition, the RV Tei index in dogs with TR significantly increased in association with pulmonary hypertension [PH(-), 0.19 +/- 0.09; PH(+), 0.65 +/- 0.14; respectively p<0.0001]. Our study has demonstrated that RV Tei index is a feasible approach to estimate RV function in dogs and is not influenced by heart rate, body weight, and aging. Further investigations are required to clarify the clinical significance of RV Tei index in dogs with right-sided cardiac diseases.  相似文献   
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