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This study describes a free-hand technique for percutaneous pancreatic biopsy in cattle with ultrasound-guidance using a 14G spinal biopsy needle. Its safety was evaluated based on 36 consecutive procedures. To assess the immediate effects of pancreatic biopsy, 31 cows were necropsied shortly after the procedure and examined. The remaining five cows were examined daily for eight days and then necropsied and examined. No life-threatening complications nor clinically detectable abnormalities were observed. Changes indicative of inflammation were not apparent in total and differential WBC counts or in total protein and fibrinogen concentrations. A small increase of amylase activity was detected in only one cow kept for the eight-day observation period. Serum lipase activity increased significantly on day four after biopsy. Urea nitrogen, creatinine, glucose and the activities of aspartate aminotransferase, alanine aminotransferase, and gamma-glutamyltransferase remained within reference ranges. Changes in the peritoneum and pancreas observed at necropsy were negligible.We conclude that percutaneous ultrasound-guided pancreatic biopsy did not appear to influence the cow's condition adversely and the procedure provided an excellent method of obtaining a pancreatic specimen for histological examination. The procedure was considered safe, fast, cost-effective, and practical when performed properly. We believe that the technique can be used in cows with suspected pancreatic disease for making an ante mortem diagnosis.  相似文献   
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Stability of bovine leukemia virus glycoprotein 51 and nonglycosylated protein 24 antigens was examined under various conditions. The glycoprotein antigen was unstable at 56 degrees C and 37 degrees C and at acidic and basic pH. The specificity of the glycoprotein 51 antigen was reduced to half by the first treatment with ethyl ether, but was not decreased further by repeated treatments. This antigen was not inactivated with triton X-100 and was resistant to lyophilization as well as to freezing and thawing. The protein 24 antigen was generally very stable under all conditions tested.  相似文献   
105.
Variance components and genetic parameters were estimated using data recorded on 740 young male Japanese Black cattle during the period from 1971 to 2003. Traits studied were feed intake (FI), feed‐conversion ratio (FCR), residual feed intake (RFI), average daily gain (ADG), metabolic body weight (MWT) at the mid‐point of the test period and body weight (BWT) at the finish of the test (345 days). Data were analysed using three alternative animal models (direct, direct + maternal environmental, and direct + maternal genetic effects). Comparison of the log likelihood values has shown that the direct genetic effect was significant (p < 0.05) for all traits and that the maternal environmental effects were significant (p < 0.05) for MWT and BWT. The heritability estimates were 0.20 ± 0.12 for FI, 0.14 ± 0.10 for FCR, 0.33 ± 0.14 for RFI, 0.19 ± 0.12 for ADG, 0.30 ± 0.14 for MWT and 0.30 ± 0.13 for BWT. The maternal effects (maternal genetic and maternal environmental) were not important in feed‐efficiency traits. The genetic correlation between RFI and ADG was stronger than the corresponding correlation between FCR and ADG. These results provide evidence that RFI should be included for genetic improvement in feed efficiency in Japanese Black breeding programmes.  相似文献   
106.
Wood is generally used as the interior material in museum storage rooms. Recently, however, the effects of volatile organic compounds (VOCs) from wood on artifacts has become a topic of great concern. The VOCs from four species of wood (western red cedar, spruce, kiri, and sugi) and their effects on artifact materials (two types of metal, seven types of pigment) were investigated using a deterioration-accelerating test, gas chromatography-mass spectrometry, X-ray diffraction analysis, and X-ray photoelectron spectroscopy. The results suggested that the influences on artifact materials varied greatly with wood species, and depended on specific components such as hinokitiol or acetic acid rather than the amount of total volatile organic compounds (TVOCs). It is a very serious problem that of the four species of wood, western red cedar (rich in hinokitiol), which has been recommended as an interior material for museum storage rooms, showed the heaviest deterioration on metal samples, and only this type of wood discolored enpaku (white lead) and rokushou (malachite, verdigris). In such storage rooms, museum artifacts should be carefully monitored. When selecting an interior material for a storage room or studying methods of preventing deterioration, it is very important to consider fully the characteristics of wood VOCs, not only the amount of TVOC.Part of this paper was presented at the 24th (Tokyo, June 2002) and 25th (Kyoto, June 2003) Annual Meeting of the Japan Society for the Conservation of Cultural Property  相似文献   
107.
In our previous study, great increases of hysteretic damping and initial slip resistance of timber joints were attained by applying axial pretension to the steel fasteners. To evaluate the effectiveness of this method, 1-year stress-relaxation measurement was carried out. Nine prestressed joints were prepared and three of them were restressed after 3 and then 6 months after the initial prestressing. All joints were exposed to indoor conditions, and relaxation of the pretension was regularly measured from time-dependent decreases of axial strain of the bolts. After measurement, the joints were subjected to cyclic and monotonic loading tests until failure. The average ratio of residual stress to the initial prestress after 1 year was about 0.23 and 0.66, respectively, for joints without restressing and those with restressing. A simulated stress-relaxation curve developed from the four-element relaxation model predicted 3% of the initial stress after 5 years. Without a regular restressing program, the initial prestressing effect therefore must be considered negligible. However, about 20% of the pre-stress level can be reasonably assumed if restressing is carried out annually. This small residual stress was found to introduce suffi cient frictional damping to signifi cantly increase the equivalent viscous damping ratio of the joints. Part of this study was presented at the 10th World Conference on Timber Engineering, Miyazaki, June 2008  相似文献   
108.
ABSTRACT:   Habitat selection of the pike gudgeon Pseudogobio esocinus esocinus (Cyprinidae) was examined in the Nakagawa River in northern Kyushu, Japan. The study area was 80 m long with two meanders comprising three riffles and two pools, located 20 km upstream from the river mouth. The pike gudgeon were visually counted underwater. Larvae and juveniles were observed in the shallow and slow-flowing water near the shores. Simultaneously, young and adult individuals were observed to inhabit the river bed. Principal component analysis and cluster analysis were applied to estimate the microhabitat selections of the larvae, juveniles and other individuals by using four variables (water depth, current velocity, particle size of substrate and amount of organic matter). The larvae and juveniles inhabited the shallow (<30 cm) and slow-flowing waters (<6.5 cm/s) near the shore; habitat selection was independent of particle size of the substrate and the amount of organic matter present. Young and adult individuals inhabited the river bed independent of the four variables.  相似文献   
109.
Donhyug  KANG  Kazuhiro  SADAYASU  Tohru  MUKAI  Kohji  IIDA  Doojin  HWANG  Kouichi  SAWADA  Kazushi  MIYASHITA 《Fisheries Science》2004,70(5):819-828
ABSTRACT:   Black porgy are hatched and released in marine ranching areas in Japan, Korea and Taiwan to maintain fisheries resources in coastal areas. If acoustic methods are used for field surveys, target strength ( TS ) information on the species is needed to convert acoustic data to biomass density. Target strength of black porgy ( Acanthopagrus schlegeli ) 15.5–32.9 cm fork length (nine individuals) was measured at 38 and 120 kHz (split beam) by ex situ measurements (cage and fishhook methods) of living fish, a tethered method with shock-frozen fish, and an acoustic scattering model, the Kirchhoff ray mode (KRM) model based on fish morphology. The ex situ TS -to-fork length ( FL , cm) relationships were TS 38kHz = 20log10 FL  − 64.6 ( r  = 0.77) and TS 120kHz = 20log10 FL  − 65.2 ( r  = 0.70). The values for the KRM model were TS 38kHz = 20log10 FL  − 64.8 ( r  = 0.88) and TS 120kHz = 20log10 FL  − 65.4 ( r  = 0.80). The agreement between the ex situ measurements and the KRM model for the mean TS was very good. In contrast, the results for the tethered method ( TS 38kHz = 20log10 FL  − 69.3 [ r  = 0.42]) differed markedly from the other two methods, perhaps because of the effects of the shock-freezing procedure in air. The results of the ex situ measurements and scattering model provide basic information for studying TS and conducting acoustic surveys of black porgy, even though the tethered method must be modified.  相似文献   
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