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111.
We osteometrically examined the skulls of the black giant squirrel (Ratufa bicolor) from three mainland populations (M. Malayan Peninsula, V. South Vietnam, and B. Burma, India and North Thailand) and from two island populations (T. Tioman, and S. Sumatra Islands). The skull in the Malayan peninsula population was significantly smaller than that of the two other mainland populations. It is consistent with Bergmann's rule as shown in the gray-bellied squirrel. The two island populations did not show obvious differences in comparison with the Malayan population in many measurements. In the proportion analysis eliminating the size factor, the differences among populations were not easily confirmed and we concluded that the osteological characters peculiar to each population could not be shown in this species. The first and second principal component scores of M, S, and T populations were intermingled, whereas the V and B populations of V and B were not separated in the chart. We pointed out that the morphological differences were demonstrated between northern and southern groups of the Isthmus of Kra in the mainland populations, and that the two island populations did not show the island-isolation effect in comparison with the M population. The adaptational variation related to feeding and locomotion could not be confirmed among populations of the black giant squirrel as shown in the proportion analysis.  相似文献   
112.
Most animal cells that are exposed to interferon (IFN) experience an increase in the activity of 2', 5'-oligoadenylate synthetase (OAS), which is an important effector of IFN's antiviral action. OAS activity has been widely used in clinical chemistry as an indicator of IFN activity. In this study, we found that OAS activity in canine serum is 46.0 +/- 40.4 nmol/dl/hr, which is 10- to 100-fold higher than in other animals such as the cat (1.9 +/- 2.1), rabbit (4.0 +/- 1.1), and guinea pig (0.3 +/- 0.6). The canine OAS protein was detected by Western blotting using a 68M-10 monoclonal anti-murine OAS antibody, and was found to be composed of at least three distinct molecular species of p40 class OAS. Among these, the 40 and 42 kDa components were determined to be the major species in serum and fibroblast cell lines, respectively.  相似文献   
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In conventional radiography systems, it is apparent that only the area immediately around the central x-ray beam can be evaluated accurately. Consequently in some instances, spinal radiography for example, several exposures are needed at various points along the body to create an accurate image for diagnosis. However, if the film and body part are in a concave shape such that the radius of the curve is equal to the film focal distance, the x-ray beam will penetrate the body and strike the film at two-dimensionally right angles in all areas. Using the spine as an example we found the curved technique had three major advantages over the traditional flat technique: lack of distortion, more uniform beam intensity due to a constant focal film distance, and improved resolution at the periphery of the radiograph because of lack of a cross over effect. It was concluded that an accurate evaluation of larger body parts can be made with minimal distortion utilizing the principles of a curved table technique.  相似文献   
115.
H5 highly pathogenic avian influenza (HPAI) viruses have spread worldwide, and antigenic variants of different clades have been selected. In this study, the national stockpiled vaccine prepared from A/duck/Hokkaido/Vac-1/2004 (H5N1) strain was evaluated for the protective efficacy against H5N8 HPAI virus isolated in Kumamoto prefecture, Japan, in April 2014. In the challenge test, all of the vaccinated chickens survived without showing any clinical signs and reduced virus shedding. It was concluded that the present stockpiled vaccine was effective against the H5N8 HPAI virus.  相似文献   
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We derived a formula for estimating the relationship between stem carbon weight and stem volume, which was calculated from DBH and tree height using a combination of stem analysis and soft X-ray densitometry. The results indicate carbon weight in a 33-year-old coastal Japanese black pine (Pinus thunbergii) forest is approximately 68,186 kg ha?1 in Yamagata Prefecture and 38,253 kg ha?1in a 42-year-old black pine forest in Hokkaido Prefecture, Japan. Also, age-related changes in the stem density following oven-drying of samples of black pine trees are small: the oven-dried density (hereafter “density”) of black pine trees in the two locations mentioned above were 425.6 (kg m?3) and 523.2 (kg m?3) respectively, which is comparable to the density (converted from basic density) of black pine of Land Use, Land-Use Change and Forestry (LULUCF) (533 kg m?3). When compared with the carbon weight by the oven-dried density of LULUCF, the carbon weights calculated from each density were 27 % lower in Yamagata and 6 % lower in Hokkaido. This difference directly affects carbon weight for large-scale estimation and thus can create an error at a regional scale. This methodology can contribute to the management of forests acting as carbon sinks.  相似文献   
118.
Field isolates of BVDV which do not show the exaltation of Newcastle disease virus (END) phenomenon (END) are rarely reported. In this study, 45 BVDV field isolates from cattle in Hokkaido prefecture in Japan were analyzed by the reverse plaque formation method, the END method and observation of cytopathic effects. END virus was detected in 34 of 45 isolates (75.6%), although 35 of 45 field isolates contained END phenomenon positive virus as the predominant virus population. We propose that END viruses are widely distributed in the field and that it is possible that the mixture of biologically distinct BVDV correlates with the appearance of disease in infected animals.  相似文献   
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