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排序方式: 共有257条查询结果,搜索用时 31 毫秒
51.
Social inequality in Israel's education system has often been analysed with top-down structural models. This study inquires, instead, how students understand their position in the stratified structure of opportunities at school. Our quantitative and qualitative data, gathered in Jewish high schools in Israel, indicate that, despite clear ethno-class distribution in academic tracking, students reject the logic of identity politics and consider ‘free will’ to be the main factor determining tracking. In light of the Jewish-Israeli national identity, which rejects class and ethnic divides, the reference point for the system of classification at school shifts to the autonomous individual. Our findings show that students use consumerist and psychological discourses to dismantle ethno-class identities and depoliticize the classification system at school.  相似文献   
52.
53.
The present article focuses on determinants of attitudes towards granting social rights to overseas labour migrants in Israeli society. The analysis is based on a national representative sample of the adult population in Israel. The findings reveal that a substantial number of respondents (both Jews and Arabs) oppose granting equal social rights (i.e. education, welfare, health, housing) to foreign workers. These attitudes can partially be explained as resulting from perceived threat to social and economic well-being of individuals as well as threat to national identity and Jewish character of the state. Part of the exclusionary attitudes that cannot be attributed to threats, are explained by individuals’ socio-economic characteristics, ethnicity and political orientation. The findings are discussed within the context of Israel as an ethno-national state.  相似文献   
54.
The Neanderthal hominid Tabun C1, found in Israel by Garrod & Bate, was attributed to either layer B or C of their stratigraphic sequence. We have used gamma-ray spectrometry to determine the230Th/234U and231Pa/235U ratios of two bones from this skeleton, the mandible and a femur. The ages calculated from these ratios depend on the uranium uptake history of the bones. Assuming a model of early U (EU) uptake the age of the Tabun C1 mandible is 34±5 ka. The EU age of the femur is 19±2 ka. The femur may have experienced continuous (linear) U uptake which would give an age of 33±4 ka, in agreement with the mandible's EU age, but implies marked inhomogeneity in U uptake history at the site. These new age estimates for the skeleton suggest that it was younger than deposits of layer C. This apparent age is less than those of other Neanderthals found in Israel, and distinctly younger than the ages of the Skhul and Qafzeh burials. This suggests that Neanderthals did not necessarily coexist with the earliest modern humans in the region. All of the more complete Neanderthal fossils from Israel are now dated to the cool period of the last glacial cycle, suggesting that Neanderthals may have arrived in this region as a result of the southward expansion of their habitable range. The young age determined for the Tabun skeleton would suggest that Neanderthals survived as late in the Levant as they did in Europe.  相似文献   
55.
A checklist of the Cladocera of Israel and Eastern Sinai   总被引:2,自引:2,他引:0  
Sixty species of Cladocera are recorded from Israel and Eastern Sinai after the examination of several collections, and include 18 new records for the area as well as 9 species known only from the literature. Chydoridae dominate the fauna, with 27 species recorded, followed by Daphniidae with 21 species.  相似文献   
56.
E Cohen  J E Casida 《Life sciences》1985,36(19):1837-1842
[35S]t-Butylbicyclophosphorothionate [( 35S]TBPS) undergoes saturable specific binding to a membrane preparation from housefly thoraxes and abdomens with apparent Kd and Bmax values at equilibrium of 0.17 microM and 2.2 pmol/mg protein at 20 degrees C. Lindane is more potent than three other isomers of hexachlorocyclohexane as a toxicant for houseflies and in displacing [35S]TBPS from this housefly membrane preparation. This correlation of similar stereospecificity for neuroactivity and interaction with the TBPS receptor extends to the Mediterranean fruit fly male attractant trimedlure and its components and analogs. The relative attractancy of t-butyl cis-4-chloro-trans-2-methylcyclohexanecarboxylate and of three less active isomers of this trans-chlorocyclohexane-carboxylate parallel their potency in the [35S]TBPS binding assay. With both trimedlure and the related cyclohexene attractant siglure the trans-isomers are more potent than the cis-isomers as attractants and in displacing [35S]TBPS. Scatchard analyses indicate that lindane binds at the same site as [35S]TBPS. The hexachlorocyclohexane isomers and trimedlure components are much more potent inhibitors with membrane preparations from houseflies than from rat brain. The housefly TBPS receptor possibly serves as a model for the primary target sites, thereby suggesting that both the insecticide and the attractant may interact with some component of the putative GABAergic nervous or neuromuscular system.  相似文献   
57.
Liver cells of 19-day-old mouse embryos were separated by peanut agglutinin (PNA) into two fractions. The fraction agglutinated with the PNA was found to be enriched for cells capable of suppressing the MLC reaction and the response to the mitogens Con A, PHA, and LPS. The fraction not agglutinated by PNA was significantly less suppressive. The response to DxS was not suppressed by any of these fractions. On the other hand, the response to LPS and DxS, but not to Con A or PHA, was expressed by the nonagglutinated fraction. It is thus inferred that the suppressor cells in the embryonic liver are separable from the potentially reactive cells.  相似文献   
58.
This short comment on Loïc Wacquant's ‘Marginality, Ethnicity, and Penality’ begins by highlighting three of Wacquant's most important interventions. It then extends the analysis by drawing on research about urban marginality in South Africa and Palestine/Israel. Whereas Wacquant focuses on the state response to urban marginality, I suggest that it is important to look beyond the state to consider how other actors have responded to the growth of precarious populations. Specifically, I point out that private security companies and residents' associations are at the forefront of efforts to police poor black South Africans, while an imperial network of security forces polices the Palestinian precariat.  相似文献   
59.
Morphological traits of Iris section Oncocyclus (Siems.) Baker in the southern Levant (Israel, Jordan, The Palestinian Authority and Sinai/Egypt) were analysed in order to clarify taxonomic relationships among taxa and the validity of diagnostic characters. Floral and vegetative characters were measured in 42 populations belonging to nine species during the peak of the flowering season in 1998–2000. Pearson's Coefficient of Racial Likelihood (CRL) was used to calculate morphological distances between populations. Twelve of the measured populations, distributed along the north-south aridity gradient in Israel, were further explored for morphological changes along the gradient. Cluster analysis revealed two major clusters: the first includes most of the dark-coloured Iris populations, with populations of I. petrana Dinsmore and I. mariae W. Barbey forming a subcluster; the second consists of all the light-coloured populations but also some dark-coloured populations. Pearson's CRL and geographical distance were significantly correlated among the dark-coloured populations. Along the geographical gradient, flower, stem and leaf size traits decrease towards the south, probably as an adaptation to aridity. This suggests that natural selection promoted the differences between populations. Almost no discrete phenotypic groups exist within the Oncocyclus species of the southern Levant except for variation in the floral colours. Most of the suggested diagnostic characters proved unreliable in that they varied continuously across populations. The taxonomical difficulties encountered in this study reflect the special evolutionary state of the Oncocyclus irises as a group in the course of speciation.  © 2002 The Linnean Society of London. Botanical Journal of the Linnean Society , 2002, 139 , 369–382.  相似文献   
60.
荒漠植物根际AM真菌的空间分布和定殖   总被引:15,自引:0,他引:15       下载免费PDF全文
 通过分析以色列荒漠地区Zygophyllum dumosum, Hammada scoparia, Artemisia herba-alba 和 Atriplex halimus 等4种灌木根际AM真菌的空间分布和定殖程度,研究了AM真菌分布和定殖与植物种类和土壤因子间的相关性。样品分别从0~10 cm,10~20 cm,20~30 cm,30~40 cm和40~50 cm等5个土层中采取,土样过2 mm筛。收集的根样切成1 cm根段,经染色后,根据感染长度确定AM真菌不同结构的定殖率;用湿筛倾析法和蔗  相似文献   
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