全文获取类型
收费全文 | 448篇 |
免费 | 40篇 |
出版年
2021年 | 5篇 |
2020年 | 3篇 |
2019年 | 7篇 |
2018年 | 5篇 |
2017年 | 8篇 |
2016年 | 10篇 |
2015年 | 20篇 |
2014年 | 18篇 |
2013年 | 18篇 |
2012年 | 23篇 |
2011年 | 21篇 |
2010年 | 20篇 |
2009年 | 16篇 |
2008年 | 17篇 |
2007年 | 21篇 |
2006年 | 21篇 |
2005年 | 19篇 |
2004年 | 12篇 |
2003年 | 13篇 |
2002年 | 11篇 |
2001年 | 11篇 |
2000年 | 14篇 |
1999年 | 11篇 |
1998年 | 8篇 |
1997年 | 6篇 |
1996年 | 14篇 |
1995年 | 10篇 |
1994年 | 8篇 |
1992年 | 7篇 |
1990年 | 5篇 |
1989年 | 5篇 |
1988年 | 6篇 |
1987年 | 3篇 |
1985年 | 4篇 |
1984年 | 4篇 |
1982年 | 3篇 |
1981年 | 3篇 |
1978年 | 9篇 |
1977年 | 6篇 |
1975年 | 6篇 |
1974年 | 4篇 |
1973年 | 3篇 |
1972年 | 5篇 |
1971年 | 3篇 |
1970年 | 3篇 |
1969年 | 3篇 |
1967年 | 4篇 |
1966年 | 5篇 |
1964年 | 2篇 |
1948年 | 2篇 |
排序方式: 共有488条查询结果,搜索用时 109 毫秒
1.
Isolation of single taste cells from lingual epithelium 总被引:1,自引:0,他引:1
A method is described for obtaining large numbers of isolatedtaste cells with identified polarity from lingual epithelium.The procedure involves incubating lingual epithelium in collagenase,staining the apical surface with fluorescein-conjugated wheatgerm agglutinin (FTTC-WGA), peeling non-gustatory surface epitheliumfrom the underlying taste buds and connective tissue, and dissociatingisolated taste buds with Ca2+-free saline. Isolated taste cellsretain their characteristic morphology for at least 30 min afterdissociation, and the apical specialization can be identifiedas a single patch of fluorescence usually located at the tipof an elongate process. Isolated taste cells are amenable tostudy with the patch-clamp technique, and whole-cell patch-clamprecordings show that isolated taste cells have membrane propertiessimilar to taste cells of intact lingual epithelium. Evidenceis presented that FITC-WGA staining does not alter the voltage-dependentionic currents of the taste cell membrane. 相似文献
2.
Peter Roper 《CMAJ》1967,96(6):319-327
Fifteen homosexuals were treated with hypnosis. The patients were selected from a general psychiatric practice and had a long history of confirmed homosexual behaviour and showed no evidence of organic or psychotic illness. The type of hypnotic induction attempted in all cases is described. In those where a satisfactory depth of hypnotic trance was achieved a change in sexual orientation was suggested to the patient.Before therapy, each patient was assessed using the Kinsey scale. Results were evaluated in terms of the patient''s subsequent behaviour and his subjective feelings. Of the 15 patients, three showed no improvement, four showed a mild improvement and eight showed a marked improvement. There was a significant correlation between the depth of hypnosis achieved and the therapeutic outcome. Those patients who reached a deep level of hypnotic trance were most likely to show a marked improvement. There were no significant correlations with other factors such as degree of homosexuality as measured on the Kinsey scale and the patient''s marital status.Treatment of homosexuals with hypnosis may produce more satisfactory results than those obtainable by other means. The best results are likely to be achieved in patients who are good hypnotic subjects. 相似文献
3.
4.
5.
6.
An Ustilago maydis ergosterol biosynthesis mutant (A14) which is partially blocked in sterol 14alpha-demethylase (P45014DM) activity is described. This mutant accumulated the abnormal 14alpha-methyl sterols, eburicol, 14alpha-methylfecosterol, and obtusifoliol, along with significant amounts of ergosterol. Although the A14 mutant grew nearly as well as the wild type, it was impaired in cell extension growth, which indicated a dysfunction in apical cell wall synthesis. The mutant was also found to be hypersensitive to the azole fungicides penconazole and tebuconazole. 相似文献
7.
T.J. Roper 《Animal behaviour》1984,32(4):1225-1235
Water-deprived rats were allowed to drink in an experimental chamber during a series of training trials, and were then presented with an empty water spout during a single test trial. Their initial response to absence of water was to bite, sniff and paw at the empty spout (spout-directed behaviour), after which they engaged in activities such as eating, grooming and exploration of the chamber. By comparison with control animals that had no expectation of water, experimental rats performed these latter activities in a bizarre ‘speeded-up’ manner, which was quantifiable as an increase in local rate. Both the occurrence of spout-directed behaviour and the increase in local rate of other activities were enhanced by increasing the prior level of water deprivation and by offering a more palatable fluid during training. The results are discussed in relation to current models of behavioural switching. 相似文献
8.
Abstract Polysphondylium pallidum strain PPHU8 grown in association with bacteria contains aspartic and cysteine proteinases. When myxamoebae were grown in axenic medium the contribution of cysteine proteinases was much lower. The proteinase activity could be altered by addition of heat-killed bacteria to axenically growing cells. This was detected as an increase in the specific activity towards N -benzoyl-L-prolyl-L-phenylalanyl-L-arginine- p -nitroanilide, a cysteine proteinase substrate, and by the appearance of cysteine proteinase bands after electrophoretic analysis. The changes were inhibited by cycloheximide, azide and dinitrophenol. All the available evidence suggests that they are due to the de novo synthesis of cysteine proteinases. 相似文献
9.
10.
McFarland (1969) suggested two mechanisms whereby a switch could occur from one activity to another: ‘competition’, which he depicted as a gradual increase in the causal-factor strength (CFS) of activity 2, and ‘disinhibition’, which he depticted as a sudden decrease in the CFS of activity 1. We postulate two further mechanisms: ‘satiation’, depicted as a gradual decrease in the CFS of activity 1, and ‘inhibition’, depicted as a sudden increase in the CFS of activity 2. We suggest that disinhibition may be a less common mechanism of behavioural switching than is usually supposed, and describe three experiments suggesting that eat/drink and drink/eat switches in the rat occur by competition and/or satiation rather than by disinhibition and/or inhibition. In experiment 1, varying degrees of water deprivation were found to affect the timing of eat/drink switches in food-deprived rats; in experiment 2, varying rates of food availability were found to affect the timing of drink/eat switches in water-deprived rats; in experiment 3, drink/eat switches were delayed by allowing rats to ‘drink’ air instead of water. 相似文献