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Brad Stiles I. C. McDonald J. W. Gerst T. S. Adams S. M. Newman 《In vitro cellular & developmental biology. Animal》1992,28(5):355-363
Summary Five continuous cell lines were initiated from embryonic tissue of the cotton boll weevilAnthonomus grandis Boheman in a commercially available, serum-free medium (Excell 401) and have undergone in excess of 60 passages. Isoenzyme
analysis confirmed that the lines originated from boll weevil tissue. Four of the lines grew as single attached cells of either
epithelioid or fibroblastoid morphology. The fifth line, BRL-AG-2, grew primarily as cell aggregates and was found to release
ecdysteroids (primarily ecdysone) into the culture medium. Evidence was also obtained suggesting that line BRL-AG-2 synthesizes
chitin. Three lines, BRL-AG-1, BRL-AG-3A, and BRL-AG-3C, could be induced to produce an antibacterial factor(s) which was
released into the culture medium. 相似文献
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Elizabeth A. Stiles Nadja B. Cech Stacy M. Dee Elizabeth P. Lacey 《Physiologia plantarum》2007,129(4):756-765
Flower color in the weedy perennial Plantago lanceolata is phenotypically plastic. Darker flowers are produced at cooler ambient temperatures, and circumstantial evidence suggests that this is adaptive. The goal of this project was to investigate the chemical basis for the color plasticity. To test the hypothesis that increased anthocyanin production at low temperatures underlies the plasticity, extracts of P. lanceolata flowers produced at warm and cool temperatures were analyzed using UV/visible spectrophotometry coupled with mass spectrometry. Mass spectrometry allowed us to compare relative abundances of individual anthocyanins. Seventeen anthocyanins, derived from both cyanidin and delphinidin branches of the anthocyanin biosynthetic pathway, were detected. Most of these significantly increased in abundance under cool conditions. Genotypes differed significantly in anthocyanin levels and in their sensitivity to temperature change. Genotypes that showed greater floral color plasticity tended to show also greater temperature sensitivity with respect to anthocyanin production. Data suggest that the temperature regulation of the anthocyanin biosynthetic pathway occurs both upstream and downstream of the divergence of the cyanidin and delphinidin branches. The degree of temperature sensitivity, i.e. phenotypic plasticity, appears to be controlled downstream, whereas the overall temperature effect appears to be controlled upstream. 相似文献
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The mature, spawned eggs of the American Eastern oyster, Crassostrea virginica Gmelin, contain yolk which interferes with the preparation of chromosomes and nuclear groups for the study of meiosis, fertilization, and karyology. Most samples of eggs cannot be studied cytogenetically until the yolk is extracted. Simple and complete removal of all interfering yolky material can be efficiently accomplished, after Carnoy fixation in 3:1 alcohol-acetic acid, by extraction for 2 hr in a micro-Soxhlet apparatus with 1:1 mixture of chloroform and methyl alcohol. Standard orcein squashes can then be routinely made of these eggs hitherto considered refractory to clear staining of chromosomes. A thimble with a fritted glass end, pore size 40 μ, is used as a receptacle for the eggs in the Soxhlet apparatus. After extraction the eggs can readily be washed off the fritted glass with the aceto-orcein staining solution. If the eggs are to be stored for some time prior to squashing and staining, 45-60% acetic acid or Carnoy's alcohol-acetic acid 3:1 can be used for the storage fluid. 相似文献
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The histological effect on and stress response of post juvenile Clarias gariepinus exposed to Qua Iboe crude oil and rig wash were investigated. Fish weighing 60–90 g and measuring 16–18 cm were exposed for 7–28 days to 8.00 ml?1 Qua Iboe crude oil and 0.0018 ml–1 rig wash, both being 0.1 of the 96 hr LC50. Blood samples of C. gariepinus were collected every seven days and evaluated for stress by measuring cortisol concentration. The gills and liver were studied and scored for Gill Alteration Index (GAI) and Hepatic Alteration Index (HAI), respectively. There was an increase in cortisol level up to the 7th and 14th day among the group exposed to Qua Iboe crude oil, with a decrease on the 21st and 28th day. The rig wash group increased in cortisol level up to the 7th day and decreased slightly on the 14th day, after which the trend became irregular. The toxic effects of the Qua Iboe crude oil and rig wash were time dependent, as shown by the histopathological alteration index (HAI) of gill and liver. After 28 days of exposure, the gills had irreparable damage due to high frequency of cellular necrosis and degeneration, whereas the liver had from moderate to severe damage due to the high frequency of cellular degeneration and inflammation. Qua Iboe crude oil and rig wash are both toxic to C. gariepinus, therefore their indiscriminate discharge to the environment must be discouraged. 相似文献
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