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51.
Neopolystoma liewi sp. n. is described from the conjunctival cavity of the Malayan box turtle Cuora amboinensis (Daudin, 1802), in Peninsular Malaysia. This is the first record of Neopolystoma in Malaysia and the fourth polystomatid species described from C. amboinensis. Of the 27 Malayan box turtles examined, 8 were found to be infected. A maximum of 2 parasites per eye and 4 individuals per host was recorded. N. liewi sp. n. differs from all other members of the genus by possessing few and short genital spines and small marginal hooks. The oncomiracidium has 64 ciliated cells arranged symmetrically about the sagittal axis.  相似文献   
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Phragmites australis (Cav.) Trin. ex Steud. has been harvested in the Muzi Swamp in Maputaland, South Africa for generations. Over the last ten years, however, a flourishing trade in this reed has developed. Concern has now been expressed that at the current levels of utilization the ecological integrity of the Muzi Swamp is being compromised, and that the current harvesting rates are not sustainable in the long term. The hypothesis was put forward that a degradation gradient exists with the most severe degradation occurring the closest to where community members enter the park, and the least degradation the furthest from this point. The results of this study, however, show no distinct degradation gradient. Yet the overall condition of the reeds in the harvesting area is poorer than in the non‐utilized area. Expansion of the current harvesting area, coupled with adaptive harvesting systems and yearly monitoring will improve the quality of the reeds within the harvesting area without affecting the harvesting quotas. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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This research investigated the proximate chemical composition of whiting roe from October to April. The highest water content (83.99%) was found in March, while the lowest (72.40%) was found in December. The highest protein (14.54%) and lipid contents (9.71%) were found in December, while the lowest protein content (7.35%) was found in January and the lowest lipid content (0.38%) in April. Crude ash content of whiting roe changed from 0.86 to 1.49%. The highest (154 kcal/100 g) and lowest energy values (64 kcal/100 g) were determined in December and April, respectively. Whiting roe can be used as a source of valuable nutrients for human nutrition.  相似文献   
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An examination of teat canal swabs established that 51 teat canals out of 68 quarters of machine-milked cows were colonized by Staphylococcus aureus. Only 31 of these quarters yielded milk from which S. aureus could be cultured, and 6 out of the 31 produced milk containing somatic cell counts in excess of 500 000/ml. No inhibitory substances could be detected in milk samples 12 h after 10 mg of sodium cloxacillin had been deposited in the test canal on 1-4 successive occasions. Teat canal swabs and milk sample cultures of the same quarters became and remained bacteriologically negative for at least a week after the last treatment. Six quarters, which according to the International Dairy Federation criteria were suffering from subclinical mastitis, became negative after local teat canal therapy. Scanning electron micrographs of one infected teat canal revealed the presence of cocci in depressions and crevices on the epithelial surface, suggesting that such cocci are not always flushed out into milk samples. Teat canal therapy should make a marked contribution to the control of bovine mastitis.  相似文献   
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A workshop was held at Onderstepoort on 2-3 July 1999 to set priorities in veterinary helminthology for South Africa. Representatives from 19 organisations attended. The workshop achieved 2 of its 3 aims, namely to identify the priority areas within the field and to set specific objectives to be achieved in addressing these needs. Seven strategies were proposed, namely, motivation, education, therapeutic, worm resistance, animal tolerance, biological control and diagnostic strategies. A follow-up session took place on 8 September 1999 and at this workshop and in subsequent meetings, preliminary action plans were developed for these strategies. It was felt that the proposed activities delineated by this process should form the basis for a National Programme for Veterinary Helminthology and a national forum is to be convened to encourage all stakeholders to consider, discuss and adopt these activities. The forum is scheduled to take place in April 2000.  相似文献   
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Bioaccumulation of chromium and nickel in selected tissues and organs of the freshwater fish Barbus marequensis was investigated. According to the monthly data, the blood accumulated the highest amount of chromium, followed by the bile and vertebrae, while the skin accumulated the lowest amount. Nickel mainly accumulated in the blood, followed by the vertebrae and gills, while the lowest nickel concentrations occurred in the fat tissue. Although significant differences (p ≤ 0,05) between localities were detected, no definite trend as to where the highest bioaccumulation had occurred could be established. The levels in the tissues and organs of B. marequensis suggested no serious chromium or nickel pollution in the study area.  相似文献   
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Examination of callus micro-grafts in Uapaca kirkiana Müell Arg. was carried out with the objective of determining early signs of graft compatibility. Leaves from U. kirkiana, U. nitida and Jatropha curcas trees were used for callus induction. Two pieces of callus were co-cultured on Murashige and Skoog (MS) medium with different supplements. Co-cultured calli were embedded in paraffin wax and dissected. The specimens were stained in safranin and fast green before viewing under a light microscope. Results showed that MS medium with 0.1 mg l−1 thidiazuron (TDZ) and 0.5 mg l−1 naphthaleneacetic acid (NAA) or 1.0 mg l−1 dichlorophenoxyacetic acid (2,4-D) and 0.5 mg l−1 NAA was effective for callus induction. There were no necrotic layers at the unions within U. kirkiana clones and provenances, but a differential growth (irregularity) between U. kirkiana and U. nitida co-cultured calli. Phenol deposits were observed at the union interfaces of U. kirkiana combinations and were high on calli derived from mature trees. Phenol deposits were absent at the union of J. curcas heterografts. Necrotic layers developed at the unions of U. kirkiana and J. curcas micro-grafts and indicating an outright graft incompatibility. Accumulation of phenol deposits at the union interfaces inhibited graft compatibility in many U. kirkiana combinations. Callus fusion technique can be used to identify partners with an outright graft incompatibility, especially for distant related plant species.  相似文献   
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