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51.
Engraulis encrasicolus is of great economic importance in the Mediterranean. However, little is known about its stock structure. Otolith shape analysis has been successfully used for fish stock identification. In this study, the stock structure of anchovy caught off the open sea and the coastal area of the Gulf of Tunis, lagoon of Bizerte and Lake of Ichkeul were investigated using otolith shape. Otolith shape was determined by Fourier analysis and then compared among specimens sampled from different areas with forward stepwise canonical discriminant analysis. Significant differences in otolith shape between the open sea and inshore anchovy groups were detected. Otolith shape of anchovy collected in the Lake of Ichkeul was distinct from the other groups. This finding suggests a clear discreteness of the open sea and the continental groups. The data highlighted the potential for using otolith shape analysis for anchovy stock identification, as well as the role of oceanographic features in determining stock separation. These findings will have major implications for anchovy fisheries management in Tunisia. By using a precautionary approach and considering the three areas as separate stocks, fisheries management strategies should be adjusted to achieve optimum sustainable production from each stock and to avoid decreases in genetic variety. 相似文献
52.
Firdissa E. Bokore Richard D. Cuthbert Ron E. Knox Harpinder S. Randhawa Colin W. Hiebert Ron M. DePauw Asheesh K. Singh Arti Singh Andrew G. Sharpe Amidou N’Diaye Curtis J. Pozniak Curt McCartney Yuefeng Ruan Samia Berraies Brad Meyer Catherine Munro Andy Hay Karim Ammar Julio Huerta-Espino Sridhar Bhavani 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2017,130(12):2617-2635
Key message
Quantitative trait loci controlling stripe rust resistance were identified in adapted Canadian spring wheat cultivars providing opportunity for breeders to stack loci using marker-assisted breeding.Abstract
Stripe rust or yellow rust, caused by Puccinia striiformis Westend. f. sp. tritici Erikss., is a devastating disease of common wheat (Triticum aestivum L.) in many regions of the world. The objectives of this research were to identify and map quantitative trait loci (QTL) associated with stripe rust resistance in adapted Canadian spring wheat cultivars that are effective globally, and investigate opportunities for stacking resistance. Doubled haploid (DH) populations from the crosses Vesper/Lillian, Vesper/Stettler, Carberry/Vesper, Stettler/Red Fife and Carberry/AC Cadillac were phenotyped for stripe rust severity and infection response in field nurseries in Canada (Lethbridge and Swift Current), New Zealand (Lincoln), Mexico (Toluca) and Kenya (Njoro), and genotyped with SNP markers. Six QTL for stripe rust resistance in the population of Vesper/Lillian, five in Vesper/Stettler, seven in Stettler/Red Fife, four in Carberry/Vesper and nine in Carberry/AC Cadillac were identified. Lillian contributed stripe rust resistance QTL on chromosomes 4B, 5A, 6B and 7D, AC Cadillac on 2A, 2B, 3B and 5B, Carberry on 1A, 1B, 4A, 4B, 7A and 7D, Stettler on 1A, 2A, 3D, 4A, 5B and 6A, Red Fife on 2D, 3B and 4B, and Vesper on 1B, 2B and 7A. QTL on 1A, 1B, 2A, 2B, 3B, 4A, 4B, 5B, 7A and 7D were observed in multiple parents. The populations are compelling sources of recombination of many stripe rust resistance QTL for stacking disease resistance. Gene pyramiding should be possible with little chance of linkage drag of detrimental genes as the source parents were mostly adapted cultivars widely grown in Canada.53.
Samia Hussein Hala Mosaad Hayam E. Rashed Shimaa Ahmed Ahmed Ragab Eman I. Ismail 《Molecular biology reports》2017,44(4):365-377
This study aimed to assess the expression of S100A4, Twist and E-cadherin (mRNA and protein) in urothelial bladder cancer, investigate the correlation between them and evaluate their association with the clinicopathological features of the disease. The study included 54 patients diagnosed as urothelial bladder cancer of different stages and grades. The expression levels of S100A4, Twist and E-cadherin (mRNA and protein) in tissue samples were determined by quantitative RT-PCR and immunohistochemistry. The expression of S100A4 and Twist was significantly upregulated while E- cadherin was significantly downregulated in urothelial bladder cancer tissues compared to the adjacent surrounding normal bladder tissues at both mRNA and protein levels (p?<?0.001). Expression levels of S100A4 and Twist were significantly higher in recurrent tumor than in non-recurrent tumors (p?<?0.001) while the expression level of E-cadherin was significantly lower in recurrent tumors than in non-recurrent tumors at both mRNA and protein levels (p?<?0.001). There was a significant positive correlation between S100A4 and Twist expressions (r?=?0.875, p?<?0.001) while significant negative correlations were found between E- cadherin and S100A4 expressions(r=- 0.803, p?<?0.001) and between E-cadherin and Twist (r?=??0.809, p?<?0.001). Up-regulation of S100A4 and Twist and down-regulation of E-cadherin in urothelial bladder cancer tissues compared to adjacent normal tissues were observed. There was a significant negative correlation between S100A4 and E- cadherin and between E- cadherin and Twist expression. However, there was a significant positive correlation between S100A4 and Twist expressions. Furthermore, the alterations in the gene expression were associated with disease stage and grade. 相似文献
54.
Expansion strategies for human mesenchymal stromal cells culture under xeno‐free conditions 下载免费PDF全文
Patrícia Aparecida Tozetti Samia Rigotto Caruso Amanda Mizukami Taisa Risque Fernandes Fernanda Borges da Silva Fabiola Traina Dimas Tadeu Covas Maristela Delgado Orellana Kamilla Swiech 《Biotechnology progress》2017,33(5):1358-1367
Choosing the culture system and culture medium used to produce cells are key steps toward a safe, scalable, and cost‐effective expansion bioprocess for cell therapy purposes. The use of AB human serum (AB HS) as an alternative xeno‐free supplement for mesenchymal stromal cells (MSC) cultivation has increasingly gained relevance due to safety and efficiency aspects. Here we have evaluated different scalable culture systems to produce a meaningful number of umbilical cord matrix‐derived MSC (UCM MSC) using AB HS for culture medium supplementation during expansion and cryopreservation to enable a xeno‐free bioprocess. UCM MSC were cultured in a scalable planar (compact 10‐layer flasks and roller bottles) and 3‐D microcarrier‐based culture systems (spinner flasks and stirred tank bioreactor). Ten layer flasks and roller bottles enabled the production of 2.6 ± 0.6 × 104 and 1.4 ± 0.3 × 104 cells/cm2. UCM MSC‐based microcarrier expansion in the stirred conditions has enabled the production of higher cell densities (5.5–23.0 × 104 cells/cm2) when compared to planar systems. Nevertheless, due to the moderate harvesting efficiency attained, (80% for spinner flasks and 46.6% for bioreactor) the total cell number recovered was lower than expected. Cells maintained the functional properties after expansion in all the culture systems evaluated. The cryopreservation of cells (using AB HS) was also successfully carried out. Establishing scalable xeno‐free expansion processes represents an important step toward a GMP compliant large‐scale production platform for MSC‐based clinical applications. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1358–1367, 2017 相似文献
55.
A novel animal-component-free medium for rabies virus production in Vero cells grown on Cytodex 1 microcarriers in a stirred bioreactor 总被引:1,自引:0,他引:1
Samia Rourou Arno van der Ark Samy Majoul Khaled Trabelsi Tiny van der Velden Héla Kallel 《Applied microbiology and biotechnology》2009,85(1):53-63
Vero cells growth and rabies production in IPT-AF medium, a property animal-component-free medium are described in this work.
Kinetics of cell growth and rabies virus (strain LP 2061) production were first conducted in spinner flasks. Over eight independent
experiments, Vero cell growth in IPT-AF medium, on 2 g/l Cytodex 1 was consistent. An average Cd (cell division number) of
3.3 ± 0.4 and a specific growth rate μ of 0.017 ± 0.006 h−1 were achieved. Such performances were comparable to those obtained in serum-containing medium (MEM + 10% FCS). Rabies virus
production on Vero cells in IPT-AF medium was also optimised in spinner flasks. The effects of multiplicity of infection (MOI),
regulation of glucose level at 1 g/l and cell washing step, were investigated. The highest virus titer was achieved when the
cells were infected at an MOI of 0.1; this level was equal to 107 FFU/ml. The step of medium exchange before cell infection can be omitted; nevertheless in this case glucose level should
be maintained at 1 g/l to avoid a decrease of specific virus productivity. Process optimisation in a 2-l stirred bioreactor
pointed out that the aeration mode was the prominent parameter that affected cell growth in IPT-AF medium and on Cytodex 1
microcarriers. An acceptable level of cell density (cell density level of 1.5 × 106 cells/ml) was achieved when cells were grown in batch mode and using headspace aeration. Nevertheless, this aeration mode
is not optimal for large-scale culture. The addition of Pluronic F68 at 0.1% at 24 h post inoculation as well as the switch
from surface aeration mode to the sparged mode, 2 days after the start of the culture, had markedly improved cell growth performance.
A cell density level of 5.5 × 106 cells/ml was reached when cells were grown in a 2-l bioreactor, on 3 g/l Cytodex 1 in IPT-AF medium and using the recirculation
culture mode. Cell infection at an MOI of 0.1 and using perfused culture, resulted in a maximal virus titer of 3.5 × 107 FFU/ml. The activity of the pooled inactivated rabies virus harvests showed a protective activity that meets WHO requirements. 相似文献
56.
Lobna Gargouri Kammoun Samia Gargouri Mohamed Rabeh Hajlaoui Mohamed Marrakchi 《Journal of Phytopathology》2009,157(9):546-551
An outbreak of Fusarium Head Blight of durum wheat occurred in 2004 being localized in sub-humid and higher semi-arid region of Northern Tunisia. A mycological survey carried out throughout these regions, revealed that 78% of the prospected fields were infested. Results of the morphological and molecular identification, showed that the most common species isolated from diseased wheat spikes was Microdochium nivale var. nivale (63.5%), followed by Fusarium culmorum (26%), F. pseudograminearum (9%) and F. avenaceum (1.5%). To evaluate mycotoxin content of naturally infected grain, the amounts of trichothecene mycotoxin deoxynivalenol (DON) in harvested grain from 45 fields were quantified by RIDASCREEN DON Enzyme Immunoassay Kit (ELISA) . This study showed that the infection levels in freshly harvested grain were very low and the maximum deoxynivalenol (DON) level of the positive samples was 53 ppb. This is the first report on the natural occurrence of DON in naturally infected wheat grain sampled from Northern Tunisia. 相似文献
57.
Samia Ammar Hayet Edziri Mohamed Ali Mahjoub Rym Chatter Abderrahman Bouraoui Zine Mighri 《Phytomedicine》2009,16(12):1156-1161
A sesquiterpenoid Bakkenolide (1), and two steroids, (3β, 22E)-Stigmasta-5, 22-diène-3-ol (Stigmasterol) (2) and stigmasterol 3β-glucoside (3), isolated from the Hertia cheirifolia (L.) chloroform extract, were evaluated respectively for their spasmolytic and anti-inflammatory activities. We note that these natural products were isolated and purified for the first time from the specie Hertia cheirifolia. Their structures have been established by spectroscopy (1 and 2D NMR experiences) and mass spectrometry. Chloroform-, ethyl acetate- and methanol-extracts were also tested for their spasmolytic and anti-inflammatory activities. Spasmolytic and anti-inflammatory screening were based respectively on the contractile response effects on rat isolated smooth muscles and on the dose-related carrageenan induced paw edema in rats. screening of the crude extracts showed spasmolytic and anti-inflammatory positive results. The antispasmodic effect of Bakkenolide was found in the same range as that of Alverine, a standard musculotropic spasmolytic agent. 相似文献
58.
Dan Hanson Philip G. Murray Amit Sud Samia A. Temtamy Andrea Superti-Furga Jill Urquhart Emma Hilton Peter Scambler Peter E. Clayton 《American journal of human genetics》2009,84(6):801-806
3-M syndrome is an autosomal-recessive primordial growth disorder characterized by significant intrauterine and postnatal growth restriction. Mutations in the CUL7 gene are known to cause 3-M syndrome. In 3-M syndrome patients that do not carry CUL7 mutations, we performed high-density genome-wide SNP mapping to identify a second locus at 2q35-q36.1. Further haplotype analysis revealed a 1.29 Mb interval in which the underlying gene is located and we subsequently discovered seven distinct null mutations from 10 families within the gene OBSL1. OBSL1 is a putative cytoskeletal adaptor protein that localizes to the nuclear envelope. We were also able to demonstrate that loss of OBSL1 leads to downregulation of CUL7, implying a role for OBSL1 in the maintenance of CUL7 protein levels and suggesting that both proteins are involved within the same molecular pathway. 相似文献
59.
Vanessa Machault Libasse Gadiaga Cécile Vignolles Fanny Jarjaval Samia Bouzid Cheikh Sokhna Jean-Pierre Lacaux Jean-François Trape Christophe Rogier Frédéric Pagès 《Malaria journal》2009,8(1):1-21
Background
Urbanization has a great impact on the composition of the vector system and malaria transmission dynamics. In Dakar, some malaria cases are autochthonous but parasite rates and incidences of clinical malaria attacks have been recorded at low levels. Ecological heterogeneity of malaria transmission was investigated in Dakar, in order to characterize the Anopheles breeding sites in the city and to study the dynamics of larval density and adult aggressiveness in ten characteristically different urban areas.Methods
Ten study areas were sampled in Dakar and Pikine. Mosquitoes were collected by human landing collection during four nights in each area (120 person-nights). The Plasmodium falciparum circumsporozoite (CSP) index was measured by ELISA and the entomological inoculation rates (EIR) were calculated. Open water collections in the study areas were monitored weekly for physico-chemical characterization and the presence of anopheline larvae. Adult mosquitoes and hatched larvae were identified morphologically and by molecular methods.Results
In September-October 2007, 19,451 adult mosquitoes were caught among which, 1,101 were Anopheles gambiae s.l. The Human Biting Rate ranged from 0.1 bites per person per night in Yoff Village to 43.7 in Almadies. Seven out of 1,101 An. gambiae s.l. were found to be positive for P. falciparum (CSP index = 0.64%). EIR ranged from 0 infected bites per person per year in Yoff Village to 16.8 in Almadies. The An. gambiae complex population was composed of Anopheles arabiensis (94.8%) and Anopheles melas (5.2%). None of the An. melas were infected with P. falciparum. Of the 54 water collection sites monitored, 33 (61.1%) served as anopheline breeding sites on at least one observation. No An. melas was identified among the larval samples. Some physico-chemical characteristics of water bodies were associated with the presence/absence of anopheline larvae and with larval density. A very close parallel between larval and adult densities was found in six of the ten study areas.Conclusion
The results provide evidence of malaria transmission in downtown Dakar and its surrounding suburbs. Spatial heterogeneity of human biting rates was very marked and malaria transmission was highly focal. In Dakar, mean figures for transmission would not provide a comprehensive picture of the entomological situation; risk evaluation should therefore be undertaken on a small scale. 相似文献60.
Alia A. Badawi Samia A. Nour Wedad S. Sakran Shereen Mohamed Sameh El-Mancy 《AAPS PharmSciTech》2009,10(4):1081-1084
Microemulsions (MEs) are clear, thermodynamically stable systems. They were used to solubilize drugs and to improve topical
drug availability. Salicylic acid (SA) is a keratolytic agent used in topical products with antimicrobial actions. The objective
of this work was to prepare and evaluate SA ME systems. Different concentrations of SA were incorporated in an ME base composed
of isopropyl myristate, water, and Tween 80: propylene glycol in the ratio of 15:1. Three ME systems were prepared: S2%, S5%, and S10% which contain 2%, 5%, and 10% of SA, respectively. Evaluation by examination under cross-polarizing microscope, measuring
of percent transmittance, pH measurement, determination of the specific gravity, assessment of rheological properties, and
accelerated stability study were carried out. The data showed that the addition of SA markedly affected the physical properties
of the base. All systems were not affected by accelerated stability tests. Stability study for 6 months under ambient conditions
was carried out for S10%. No remarkable changes were recorded except a decrease in the viscosity value after 1 month. The results suggested that ME
could be a suitable vehicle for topical application of different concentrations of SA. 相似文献