全文获取类型
收费全文 | 168篇 |
免费 | 14篇 |
出版年
2021年 | 1篇 |
2020年 | 2篇 |
2018年 | 9篇 |
2017年 | 5篇 |
2016年 | 4篇 |
2015年 | 9篇 |
2014年 | 9篇 |
2013年 | 8篇 |
2012年 | 11篇 |
2011年 | 11篇 |
2010年 | 9篇 |
2009年 | 2篇 |
2008年 | 3篇 |
2007年 | 6篇 |
2006年 | 12篇 |
2005年 | 9篇 |
2004年 | 6篇 |
2003年 | 12篇 |
2002年 | 2篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 1篇 |
1984年 | 2篇 |
1982年 | 2篇 |
1981年 | 5篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1972年 | 3篇 |
1968年 | 1篇 |
1966年 | 1篇 |
1963年 | 1篇 |
排序方式: 共有182条查询结果,搜索用时 46 毫秒
81.
Jan Havlíček Vít Třebický Jaroslava Varella Valentova Karel Kleisner Robert Mbe Akoko Jitka Fialová Rosina Jash Tomáš Kočnar Kamila Janaina Pereira Zuzana Štěrbová Marco Antonio Corrêa Varella Jana Vokurková Ernest Vunan S. Craig Roberts 《Evolution and human behavior》2017,38(2):217-226
The morphology of human female breasts appears to be unique among primates due to their permanent fat deposits. It has been previously suggested that female breast morphology arose as a result of sexual selection. This is supported by evidence showing that women with larger breasts tend to have higher estrogen levels; breast size may therefore serve as an indicator of potential fertility. However, breasts become less firm with age and parity, and breast shape could thus also serve as a marker of residual fertility. Therefore, cross-culturally, males are hypothesized to prefer breast morphology that indicates both high potential and residual fertility. To test this, we performed a survey on men's preferences for breast morphology in four different cultures (Brazil, Cameroon, the Czech Republic, Namibia). As stimuli, we used two sets of images varying in breast size (marker of potential fertility) and level of breast firmness (marker of residual fertility). Individual preferences for breast size were variable, but the majority of raters preferred medium sized, followed by large sized breasts. In contrast, we found systematic directional preferences for firm breasts across all four samples. This pattern supports the idea that breast morphology may serve as a residual fertility indicator, but offers more limited support for the potential fertility indicator hypothesis. Future studies should focus on a potential interaction between the two parameters, breast size and firmness, which, taken together, may help to explain the relatively large variation in women's breast sizes. 相似文献
82.
83.
Dr. John E. Hesketh Jaroslava Ciesielski-Treska Dominique Aunis 《Cell and tissue research》1981,218(2):331-343
Summary Immunofluorescence studies of bovine chromaffin cells in culture with specific antibodies against dopamine-gb-hydroxylase gave a distinct punctate pattern of labelling, reflecting the distribution of chromaffin granules. There was strong staining of cell extensions and growth cones. Linear arrays of fluorescent dots were observed, suggesting an association of granules with a filamentous cytoskeleton. Labelling of neuritic processes was periodic, perhaps indicative of a packaging of secretory granules.Chromaffin cells stained strongly with specific anti-actin antisera. Fine filament bundles were observed, and also diffuse staining, some punctate labelling and staining of the plasma membrane or sub-membranous cytoplasm. Growth cones and non-terminal cytoplasmic varicosities contained significant amounts of actin. Colchicine (5×10-5M) caused retraction of neuritic extensions and formation of lateral growth cones. Cytochalasin (10g/ml) caused ballooning of terminal growth cones and non-terminal cytoplasmic varicosities. Phalloidin (10-4M) stimulated microspike formation. The results are discussed in terms of the role of the cytoskeleton in growth cone formation, cell-substratum contacts and the transport of chromaffin granules. 相似文献
84.
Jaroslava Halper 《Experimental cell research》1990,187(2)
This study reports on the specific binding of [3H]heparin to human adrenocortical carcinoma cell line SW-13. Heparin binding to SW-13 cells is specific, saturable, and time- and temperature-dependent with maximum binding occurring between 90 and 120 min at 22 °C. Scatchard analysis revealed two classes of binding sites. The apparent Kd for high-affinity receptors is 2.14 × 10−8 M with 1.48 × 106 sites per cells. Six other tested mammalian cell lines also have specific binding sites for heparin. 相似文献
85.
Abstract— Abstract-Intracellular pH in the brain was evaluated by the bicarbonate-carbonic acid method and from the creatine phosphokinase equilibrium, in rats exposed to 6–40 % CO2 for 45 min. There was a very good agreement between the two methods, indicating that the creatine phosphokinase equilibrium in vivo shows the pH dependence predicted from previous in vitro studies. The stepwise increase in the tissue CO2 tension from 45 to 265 mm Hg resulted in a lowering of the intracellular pH from 7.04 to 6.68. The regulation of intracellular pH in hypercapnia was far better than that which can be predicted from physicochemical buffering alone, and calculations indicate that the intracellular buffer base concentration increased by more than 10 mequiv./kg at the maximal Pco2 values encountered. 相似文献
86.
87.
Tom Jza Jaroslava Frouzov Uwe Brmick Vladislav Dratík Tom Mrkvi
ka Jan Kube
ka 《International Review of Hydrobiology》2012,97(6):509-525
The fish stock of a deep temperate, mesotrophic lake was sampled at different depths using a fixed‐frame fry trawl, during two nights in mid‐September 2009. Additionally, horizontal and vertical hydroacoustics were used simultaneously to evaluate fish abundance and biomass estimates obtained by the trawl. Roach Rutilus rutilus and smelt Osmerus eperlanus were the dominant species of young‐of‐the‐year (YOY) fish in the trawl catches from the surface layers (0–9 m). Bleak Alburnus alburnus dominated the catch of older fish in the upper part of the surface profile (0–6 m). Around the thermocline (9–13 m) smelt dominated the catches of both the YOY and older fish. Beneath the thermocline (13–36 m) vendace Coregonus albula dominated the catch of YOY fish, and smelt was the only species of older fish in the trawl catches. Species composition, abundance and biomass of the YOY and older fish were heterogeneous throughout the depth profiles of the lake, but only abundance differed significantly between the layers. The hydroacoustics gave relatively similar estimates of abundance and biomass to those obtained by the trawl in all the depths sampled. Our results indicate that there is a clear separation of small fish of different species along the vertical profile of a deep temperate lake during the night, and an unequal vertical distribution of fish abundance and biomass. The similarity of the trawl and hydroacoustics estimates of abundances and biomass indicated that the trawl sampling did not cause important avoidance reactions of small fish during the night in this deep temperate lake (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
88.
Walter G. Gonzalez Khoa Pham Jaroslava Miksovska 《The Journal of biological chemistry》2014,289(46):32201-32213
KChIP3 (potassium channel interacting protein 3) is a calcium-binding protein that binds at the N terminus of the Kv4 voltage-gated potassium channel through interactions at two contact sites and has been shown to regulate potassium current gating kinetics as well as channel trafficking in cardiac and neuronal cells. Using fluorescence spectroscopy, isothermal calorimetry, and docking simulations we show that the novel potassium current activator, NS5806, binds at a hydrophobic site on the C terminus of KChIP3 in a calcium-dependent manner, with an equilibrium dissociation constant of 2–5 μm in the calcium-bound form. We further determined that the association between KChIP3 and the hydrophobic N terminus of Kv4.3 is calcium-dependent, with an equilibrium dissociation constant in the apo-state of 70 ± 3 μm and 2.7 ± 0.1 μm in the calcium-bound form. NS5806 increases the affinity between KChIP3 and the N terminus of Kv4.3 (Kd = 1.9 ± 0.1 μm) in the presence and absence of calcium. Mutation of Tyr-174 or Phe-218 on KChIP3 abolished the enhancement of Kv4.3 site 1 binding in the apo-state, highlighting the role of these residues in drug and K4.3 binding. Kinetic studies show that NS5806 decreases the rate of dissociation between KChIP3 and the N terminus of KV4.3. Overall, these studies support the idea that NS5806 directly interacts with KChIP3 and modulates the interactions between this calcium-binding protein and the T1 domain of the Kv4.3 channels through reorientation of helix 10 on KChIP3. 相似文献
89.
Jaroslava Folbergrová Pavel Ješina Renata Haugvicová Václav Lisý Josef Houštěk 《Neurochemistry international》2010,56(3):394-403
Our previous work demonstrated the marked decrease of mitochondrial complex I activity in the cerebral cortex of immature rats during the acute phase of seizures induced by bilateral intracerebroventricular infusion of dl-homocysteic acid (600 nmol/side) and at short time following these seizures. The present study demonstrates that the marked decrease (~60%) of mitochondrial complex I activity persists during the long periods of survival, up to 5 weeks, following these seizures, i.e. periods corresponding to the development of spontaneous seizures (epileptogenesis) in this model of seizures. The decrease was selective for complex I and it was not associated with changes in the size of the assembled complex I or with changes in mitochondrial content of complex I. Inhibition of complex I was accompanied by a parallel, up to 5 weeks lasting significant increase (15–30%) of three independent mitochondrial markers of oxidative damage, 3-nitrotyrosine, 4-hydroxynonenal and protein carbonyls. This suggests that oxidative modification may be most likely responsible for the sustained deficiency of complex I activity although potential role of other factors cannot be excluded. Pronounced inhibition of complex I was not accompanied by impaired ATP production, apparently due to excess capacity of complex I documented by energy thresholds. The decrease of complex I activity was substantially reduced by treatment with selected free radical scavengers. It could also be attenuated by pretreatment with (S)-3,4-DCPG (an agonist for subtype 8 of group III metabotropic glutamate receptors) which had also a partial antiepileptogenic effect.It can be assumed that the persisting inhibition of complex I may lead to the enhanced production of reactive oxygen and/or nitrogen species, contributing not only to neuronal injury demonstrated in this model of seizures but also to epileptogenesis. 相似文献
90.
Peter Wenzl Haobing Li Jason Carling Meixue Zhou Harsh Raman Edie Paul Phillippa Hearnden Christina Maier Ling Xia Vanessa Caig Jaroslava Ovesná Mehmet Cakir David Poulsen Junping Wang Rosy Raman Kevin P Smith Gary J Muehlbauer Ken J Chalmers Andris Kleinhofs Eric Huttner Andrzej Kilian 《BMC genomics》2006,7(1):1-22