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111.
There is a growing body of data reporting the association of genetic alterations in chromosome 9P21 with the risk of developing cancer. In the current study, we studied the association of a genetic variant in CDKN2A/B, rs1333049, with the risk of developing breast cancer. A total of 339 participants with and without breast cancer entered to the study. Genotyping was done by the TaqMan real-time polymerase chain reaction (RT-PCR) method and gene expression analysis was ran by RT-PCR. Our data showed that the minor allele homozygote in the total population was 10%, whereas for heterozygote was 38%. The dominant genetic model demonstrated that individuals with breast cancer had advanced TNM classification. Moreover, the logistic regression revealed that individuals who had CC/CG genotypes might have an enhanced risk of developing breast cancer when compared to the holders of GG genotype (e.g., OR = 2.8; 95% CI,1.4–5.4; p = .001), after regulated for confounders; age and body mass index. Furthermore, our analysis showed that the CDKN2A/B gene was downregulated in patients (p < .001). We showed a meaningful relationship of CDKN2A/B with the risk of breast cancer, cancer, showing the importance of studies in great sample size and several centers for studying the value of the marker as a risk classification in the management of patients with breast cancer.  相似文献   
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To enhance table olive tree authentication, relationship, and productivity, we consider the analysis of 18 worldwide table olive cultivars (Olea europaea L.) based on morphological, biological, and physicochemical markers analyzed by bioinformatic and biostatistic tools. Accordingly, we assess the relationships between the studied varieties, on the one hand, and the potential productivity–quantitative parameter links on the other hand. The bioinformatic analysis based on the graphical representation of the matrix of Euclidean distances, the principal components analysis, unweighted pair group method with arithmetic mean, and principal coordinate analysis (PCoA) revealed three major clusters which were not correlated with the geographic origin. The statistical analysis based on Kendall’s and Spearman correlation coefficients suggests two highly significant associations with both fruit color and pollinization and the productivity character. These results are confirmed by the multiple linear regression prediction models. In fact, based on the coefficient of determination (R 2) value, the best model demonstrated the power of the pollinization on the tree productivity (R 2 = 0.846). Moreover, the derived directed acyclic graph showed that only two direct influences are detected: effect of tolerance on fruit and stone symmetry on side and effect of tolerance on stone form and oil content on the other side. This work provides better understanding of the diversity available in worldwide table olive cultivars and supplies an important contribution for olive breeding and authenticity.  相似文献   
115.
ABSTRACT

This article analyses the political and media discourses on Roma in Hungary, Finland and the UK, in relation to the local Roma in these countries as well as those who migrated from Central and Eastern Europe countries following the fall of communism. The authors have analysed left of centre and right of centre major newspapers in these three countries, focusing on specific case studies which were the foci of public debates during the last two decades. We also examined a common case study in 2013 (“blond Maria”) that was discussed throughout Europe. In each news paper, the constructions of Roma, local and migrant, and the changes to related discourses over the period were studied. In conclusion, we examine the multi-layered processes of social and political borderings in Europe which dominate discourses on Roma, “indigenous” and migrant, and the extent to which they constitute a coherent “European” construction of “the Roma”.  相似文献   
116.

Background

The ability to digest lactose after weaning, namely, lactase persistence (LP), is encoded by polymorphisms in the MCM6 gene and varies widely in frequency among different human populations. Although, evolution of LP-related genetic variants was investigated in many groups of Sub-Saharan African, Middle Eastern, and European ancestry, only few studies have focused on populations from North Africa and no data are especially available from the Tunisian one. For this reason, there is an urgent need to investigate the frequency patterns at these loci in Tunisia since this adaptive trait is implicated in health.

Methods

Forty SNPs covering the LCT/MCM6 genes and including the two functional variants ??13,910 C > T and ??22,018 G > A were genotyped in 117 Tunisian individuals using the Sequenom Mass Array technology. The observed nucleotide and haplotype patterns of variation were then compared with those of several African, European, and Mediterranean human groups for which comparable data were publicly available. Admixture analysis on a 5 Mb genomic region surrounding the LCT/MCM6 loci was also performed by extracting genotypes from a previously generated genome-wide dataset in order to deepen the reconstruction of the evolutionary history of these loci.

Results

We found that lactase non-persistence (LNP)-related alleles and haplotypes were predominantly present in the examined population. A clear differentiation between Tunisian, African, and North European/North Italian samples was found, while the Tunisian population showed more genetic affinity to Central and South Italian groups.

Conclusions

Our study provided a first report of LP-associated alleles and haplotypes in the Tunisian population. We highlighted a gradient followed by LP diffusion from Europe to North Africa. Based on the rich historic background of Tunisia, we suggest that this adaptive trait was introduced in that geographic region by a relatively recent gene flow.
  相似文献   
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Seasonal variations in phytoplankton species composition (frequencies) and densities (cell numbers) in nine North African coastal lakes selected in Morocco (Merja Sidi Bou Rhaba, Zerga and Bokka), Tunisia (Chitane, Ichkeul and Korba lakes) and Egypt (Edku, Burullus and Manzala lakes) were investigated during 1998. The main aim was to provide gase-line information about overall phytoplankton diversity and how phytoplanktoncharacteristics differ between these contrasting aquatic systems.Water samples were collected at approximately three monthly intervals and phytoplankton analysis revealed marked seasonal and spatial differences in the quantitative and qualitative composition of the communities at each site. The Egyptian lakes generally had larger crops (Manzala and Burullus had mean crop densities of more than 104 cells ml–1) but in the western North African sites only Korba and Sidi Bou Rhaba had closely comparable densities. Algae belonging to Bacillariophyceae, Chlorophyceae, Chrysophyceae, Cyanophyceae, Dinophyceae and Euglenophyceae were recorded. Taxa representative of all these algal groups occurred in two lakes (Korba and Manzala) but at the other seven sites only some of the groups were present.The Chlorophyceae was the most dominant group in lakes Burullus, Manzala, Korba and Sidi Bou Rhaba whereas Bacillariophyceae were dominant in lakes Zerga, Bokka and Edku. In Ichkeul and acidic Chitane the Dinophyceae and the Cyanophyceae were the dominant groups, respectively. The maximum percentage of Euglenophyceae occurred in Edku Lake but this group was absent in Sidi Bou Rhaba and Ichkeul. Cyanophyceans were present in significant numbers in all investigated lakes except in Ichkeul. A total of fifty-three genera were recorded, 17 of Chlorophyceae, 18 of Bacillariophyceae, 11 of Cyanophyceae, 3 of Chrysophyceae, 2 of Euglenophyceae and 2 of Dinophyceae. The maximum number of species (34) occurred in Burullus Lake and the minimum (6) in Ichkeul Lake. Only one lake (acidic Chitane) possessed species indicative of oligotrophic conditions. The Nile Delta lakes were the most species diverse sites.The phytoplankton communities of the nine North African lakes were composed entirely of cosmopolitan species but with one new species (Cyclotella choctawatcheeana) was recorded for the region. The data presented provide a contemporary account of the levels of algal diversity present in these sites at the end of the 20th century. The relevance of phytoplankton communities to assessment of lake status and future monitoring studies in the region is emphasised.  相似文献   
118.
Exploitation of land and water resources has increased rapidly in North Africa during the 20th century, paralleling regional population growth. As part of the CASSARINA Project (see Flower, 2001), the environmental status of nine wetland lakes in Morocco, Tunisia, and Egypt was evaluated. All are conservationally important habitats and several are Ramsar Sites (internationally recognized bird reserves) and several support significant fisheries. All are shallow (<2 m in depth) but vary greatly in area.Where available, documentary information on relevant 20th century changes is given. Survey transects for aquatic vegetation were established and used to provide baseline ecological information on the aquatic plant communities during 1997–1999. Unusually, one site (Tunisian Megene Chitane) supported acidophilous vegetation (some taxa being nationally rare). Aquatic macrophytes declined catastrophically at two sites during the 1990s. Merja Bokka was drained in 1998 and, at Garaet El Ichkeul, fringing Phragmites and Scirpus spp. were lost, mainly as a result of salinity changes. Elsewhere, fringing macrophytes remain (extensively so in the Nile Delta lakes) common, despite major land reclamation and water quality problems, or are degraded by grazing (Merja Zerga). Marginal vegetation during 1997/98 changed markedly at Megene Chitane due to water level lowering.Documentary records indicated that throughout the 20th century, reclamation and hydrologic modifications, mainly for agricultural purposes, affected all nine sites. The loss of lake area by reclamation is substantial for the Nile Delta lakes (Edku, Burullus and Manzala). For the western sites, some data indicate increasing salinity in the most recent decade but the Delta lakes have become generally fresher during the 20th century, as supply of Nile water for irrigation increased.Despite intense human disturbance, many of the remaining CASSARINA sites still support regions of high aquatic diversity. Spatial scale monitoring of the larger sites for seasonal and inter-annual changes in open water area and in aquatic plant abundances is a key requirement for integrated environmental change assessment in the 21st century.  相似文献   
119.
Sediment from 9 lakes and lagoons in 3 North African countries was analysed for a suite of organochlorine insecticides and polychlorinated biphenyls (PCBs). Residues of -HCH and pp-DDE were detected in most cores, and radiometric dating of the sediment enabled time profiles to be constructed which are indicative of recent use of the insecticide lindane and previous use of the insecticide DDT in the region. Absolute concentrations of these pesticides were relatively low compared to reported values for other world-wide locations, but exceeded recommended Canadian and Dutch environmental quality standards at several sites. Maximum fluxes of -HCH and pp-DDE (190 and 95 g m–2 yr–1, respectively) were relatively high and comparable to some sediments in North America and the United Kingdom. Other organochlorine pesticides including dieldrin were detected at low levels in some samples. Selected PCB congeners were detected at trace levels at 2 sites only, indicating low levels of industrial contamination at the sampling locations. Tropical and sub-tropical regions of the world have been suggested to be contemporary sources of globally distributed organochlorine contaminants. These data are discussed with respect to this hypothesis.  相似文献   
120.
The goal of this study was to generate cell lines from a variety of insect tissues that could be useful for developing in vitro assays with tissue-specific properties. In this article, we describe the establishment of new cell cultures from differentiated (primarily neural) and undifferentiated tissues (primarily embryonic) and their initial characterization. Cell lines were established from the following tissues of the budworm, Heliothis virescens, and the bollworm, Helicoverpa zea: larval ventral nerve cords (4 lines), larval midguts (1 line), adult ovaries (1 line), and embryonic tissues (11 lines). Cell lines were primarily characterized by morphological examination and polymerase chain reaction (PCR) (both deoxyribonucleic acid amplification fingerprinting and inter-simple sequence repeats PCR).  相似文献   
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