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1.
云南楼梯草属研究随记   总被引:5,自引:1,他引:4  
王文采 《植物研究》2003,23(3):257-260
描述了云南荨麻科楼梯草属三新种和一新变种;列出了勐仑楼梯草与骤尖楼梯草的区别特征,据此说明勐仑楼梯草是一个比骤尖楼梯草原始的独立种,不赞同将其归并,而认为应予以恢复。  相似文献
2.
讨论了Clematis eriopoda Maxim.和sect.Atragenopsis Boiss.的地位,认为这二分类群均应成立;描述了2新种,1新变种;过去长期被归并的卷萼铁线莲C.tubulosa得到恢复;Clematisheracleifoliavar.ichangensis被转移改作卷萼铁线莲的变种;首次给出光叶铁线莲Clematisglabrifolia的果实的形态描述。  相似文献
3.
讨论了Clematis eriopoda Maxim和sect.Atragenopsis Boiss.的地位,认为这二分类群均应成立;描述了2新种,1新变种;过去长期被归并的卷萼铁线莲C.tubulosa得到恢复;Clematis heracleifolia var.ichangensis被转移改作卷萼铁线莲的变种;首次给出光叶铁线莲Clematis glabrifolia的果实的形态描述。  相似文献
4.
Linnaeus (1758, 1764,1767) 将产于南美的蜡蝉laternaria和产于中国的蜡蝉candelaria 分别描记于 Cicada、Laternaria 和 Fulgora 三个不同的属下,由此产生了命名学上的一个问题.一些学者将 candelaria 及东洋区的相关种类归为 Fulgora 下(如 Distant, 1906, 1916; Baker, 1925);而另一些学者则将laternaria 及新热带区的相关种类归于 Fulgora 下(如 Metcalf, 1947).这一问题直到1954年经国际动物学命名委员会(ICZN,1954)裁决才得以解决.ICZN (1954)的决议包括:将 laternaria 作为Fulgora 的模式种及将新热带区的相关种类归于 Fulgora;Fulgora 为蜡蝉科的模式属;将 Laternaria 作为无效名,并以 Pyrops 取代,其模式种为 candelaria.然而,国际动物学命名委员会的这一决议并未得到一些学者的注意.例如,Lallemand (1963)在其"亚洲及澳大利亚的蜡蝉科的订正研究"中仍将东洋区种类归于蜡蝉属 Fulgora.在我国,Fulgora 则一直被广泛使用出现在研究论文(如周尧及王思政(见周尧、王思政及黄桔,1985))、教科书(如周尧,1980;古德祥及陈振跃,1980;袁锋及张雅林,1996)及一些区系专著中 (如周尧等,1985;周尧等,1987;李子忠,1987;彭建文及周石涓,1992).最近,日本学者 Sato & Nagai (1994)又描记了东南亚蜡蝉属 Fulgora 的四个新种和新亚种,并将锥头蜡蝉 Saiva cultellata (Walker)移入蜡蝉属 Fulgora.为了澄清命名学上的这一混淆,以保持名称的稳定性,本文给出了东方蜡蝉属 Pyrops 的全部种类名录,同时建立新组合50个,恢复原有组合12个,并将 Pyrops rhli Schmidt 修订为 Pyrops ruehli Schmidt.  相似文献
5.
Re-exposure to drug-related cues elicits drug-seeking behaviour and relapse in both humans and laboratory animals even after months of abstinence. Identifying neural and molecular substrates underlying conditioned heroin-seeking behaviour will be helpful in understanding mechanisms behind opiate relapse. In humans and animals, brain areas activated by natural reward-related stimuli (e.g. food, sex) do not show a complete overlap with those activated by stimuli associated with drugs of abuse, suggesting the involvement of different circuitry. To that end, we investigated neural reactivity by measuring immediate early gene (IEG) expression patterns in mesocorticolimbic system target areas following cue-induced reinstatement of heroin seeking and compared those IEG expression patterns to what was measured during natural reward (sucrose)-seeking behaviour. Animals were trained to administer heroin associated with a compound audio-visual cue. Re-exposure to the cue after 3 weeks of withdrawal reinstated heroin-seeking behaviour, which resulted in IEG expression of ania-3, MKP-1, c-fos and Nr4a3 in the medial prefrontal cortex (mPFC), and of ania-3 in the orbital frontal cortex (OFC) and nucleus accumbens core (NAC). The expression patterns for heroin-seeking behaviours did not generalize to sucrose-seeking behaviours, indicating that the two behaviours involve different connectivity pathways of neuronal signalling.  相似文献
6.
Alcoholism is a complex disorder that represents an important contributor to health problems worldwide and that is difficult to encompass with a single preclinical model. Additionally, alcohol (ethanol) influences the function of many neurotransmitter systems, with the interaction at γ-aminobutyric acidA (GABAA) receptors being integral for ethanol's reinforcing and several withdrawal-related effects. Given that some steroid derivatives exert rapid membrane actions as potent positive modulators of GABAA receptors and exhibit a similar pharmacological profile to that of ethanol, studies in the laboratory manipulated GABAergic steroid levels and determined the impact on ethanol's rewarding- and withdrawal-related effects. Manipulations focused on the progesterone metabolite allopregnanolone (ALLO), since it is the most potent endogenous GABAergic steroid identified. The underlying hypothesis is that fluctuations in GABAergic steroid levels (and the resultant change in GABAergic inhibitory tone) alter sensitivity to ethanol, leading to changes in the positive motivational or withdrawal-related effects of ethanol. This review describes results that emphasize sex differences in the effects of ALLO and the manipulation of its biosynthesis on alcohol reward-versus withdrawal-related behaviors, with females being less sensitive to the modulatory effects of ALLO on ethanol-drinking behaviors but more sensitive to some steroid manipulations on withdrawal-related behaviors. These findings imply the existence of sex differences in the sensitivity of GABAA receptors to GABAergic steroids within circuits relevant to alcohol reward versus withdrawal. Thus, sex differences in the modulation of GABAergic neurosteroids may be an important consideration in understanding and developing therapeutic interventions in alcoholics.  相似文献
7.
Previous experiments on behavioral momentum have shown that relative resistance to extinction of operant behavior in the presence of a discriminative stimulus depends upon the baseline rate or magnitude of reinforcement associated with that stimulus (i.e., the Pavlovian stimulus-reinforcer relation). Recently, we have shown that relapse of operant behavior in reinstatement, resurgence, and context renewal preparations also is a function of baseline stimulus-reinforcer relations. In this paper we present new data examining the role of baseline stimulus-reinforcer relations on resistance to extinction and relapse using a variety of baseline training conditions and relapse operations. Furthermore, we evaluate the adequacy of a behavioral momentum based model in accounting for the results. The model suggests that relapse occurs as a result of a decrease in the disruptive impact of extinction precipitated by a change in circumstances associated with extinction, and that the degree of relapse is a function of the pre-extinction baseline Pavlovian stimulus-reinforcer relation. Across experiments, relative resistance to extinction and relapse were greater in the presence of stimuli associated with more favorable conditions of reinforcement and were positively related to one another. In addition, the model did a good job in accounting for these effects. Thus, behavioral momentum theory may provide a useful quantitative approach for characterizing how differential reinforcement conditions contribute to relapse of operant behavior.  相似文献
8.
After examining a large number of type and authoritative specimens of Schizophragma Siebold & Zucc., S. elliptifolium C. F. Wei and S. integrifolium var. glaucescens Rehder were reduced to synonyms of S. hypoglaucum Rehder and S. integrifolium f. cordatum S. Y. Wang was reduced to synonym of S. corylifolium Chun. Schizophragma crassum var. ellipticum J. Anthony was treated as the correct name of S. crassum var. hsitaoanum (Chun) C. F. Wei. The name S. integrifolium var. minus Rehder is reinstated. The taxonomic treatment is supported by leaf epidermal characters.  相似文献
9.
After examining a large number of type and authoritative specimens of Schizophragma Siebold & Zucc., S. elliptifolium C. F. Wei and S. integrifolium var. glaucescens Rehder were reduced to synonyms of S. hypoglaucum Rehder and S. integrifolium f. cordatum S. Y. Wang was reduced to synonym of S. corylifolium Chun. Schizophragma crassum var. ellipticum J. Anthony was treated as the correct name of S. crassum var. hsitaoanum (Chun) C. F. Wei. The name S. integrifolium var. minus Rehder is reinstated. The taxonomic treat-ment is supported by leaf epidermal characters.  相似文献
10.
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