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101.
Juan Carlos Alonso Carlos Palacín Alejandro Onrubia Rachid Aboulouafae Mohamed Amezian Abdelaziz El Idrissi Essougrati 《Ostrich》2016,87(3):277-280
A Great Bustard Otis tarda survey carried out in spring 2015 in Morocco confirmed the decline of this highly endangered population. Bustards were only seen at two of the seven leks occupied ten years ago. The total number of birds counted was 40-44, which represents a 40% decline over the last decade. The sex-ratio was still strongly female-biased (1 male: 3 females), but less than in previous surveys, which suggests that trophy hunting has not been the major mortality cause in recent times. The productivity was 0.29-0.33 juveniles per female, the highest ever recorded in this population, suggesting that breeding success doesn’t represent the main problem for the survival of this population. Based on the recent development of the power line network at some areas, the main threat today is probably collision with power lines. Reducing this mortality cause should be considered a high conservation priority. 相似文献
102.
Manal S. Fawzy Mohammad H. Hussein Eman Z. Abdelaziz Hussain A. Yamany Hussein M. Ismail Eman A. Toraih 《PloS one》2016,11(4)
Chronic obstructive pulmonary disease (COPD) is a multifactorial chronic respiratory disease, characterized by an obstructive pattern. Understanding the genetic predisposition of COPD is essential to develop personalized treatment regimens. MicroRNAs (miRNAs) are small, endogenous, non-coding RNAs that modulate the expression levels of specific proteins based on sequence complementarity with their target mRNA molecules. Emerging evidences demonstrated the potential use of miRNAs as a disease biomarker. This pilot study aimed to investigate the association of the MIR-196a2 rs11614913 (C/T) polymorphism with COPD susceptibility, the clinical outcome and bronchodilator response to short-acting β2-agonist. Genotyping of rs11614913 polymorphism was determined in 108 COPD male patients and 116 unrelated controls using real-time polymerase chain reaction technology. In silico target prediction and network core analysis were performed. COPD patients did not show significant differences in the genotype distribution (p = 0.415) and allele frequencies (p = 0.306) of the studied miRNA when compared with controls. There were also no associations with GOLD stage, dyspnea grade, disease exacerbations, COPD assessment test for estimating impact on health status score, or the frequency of intensive care unit admission. However, COPD patients with CC genotype corresponded to the smallest bronchodilator response after Salbutamol inhalation, the heterozygotes (CT) had an intermediate response, while those with the TT genotype showed the highest response (p < 0.001). In conclusion MIR-196a2 rs11614913 polymorphism is associated with the bronchodilator response of COPD in our sample of the Egyptian population, generating hypothesis of the potential use of MIR-196a2 variant as a pharmacogenetic marker for COPD. 相似文献
103.
Moulay Abdelaziz El Alaoui Marouane Melloul Sanaa Alaoui Amine Hamid Stambouli Aziz El Bouri Abdelmajid Soulaymani Elmostafa El Fahime 《PloS one》2013,8(10)
The extraction and purification of nucleic acids is the first step in most molecular biology analysis techniques. The objective of this work is to obtain highly purified nucleic acids derived from Cannabis sativa resin seizure in order to conduct a DNA typing method for the individualization of cannabis resin samples. To obtain highly purified nucleic acids from cannabis resin (Hashish) free from contaminants that cause inhibition of PCR reaction, we have tested two protocols: the CTAB protocol of Wagner and a CTAB protocol described by Somma (2004) adapted for difficult matrix. We obtained high quality genomic DNA from 8 cannabis resin seizures using the adapted protocol. DNA extracted by the Wagner CTAB protocol failed to give polymerase chain reaction (PCR) amplification of tetrahydrocannabinolic acid (THCA) synthase coding gene. However, the extracted DNA by the second protocol permits amplification of THCA synthase coding gene using different sets of primers as assessed by PCR. We describe here for the first time the possibility of DNA extraction from (Hashish) resin derived from Cannabis sativa. This allows the use of DNA molecular tests under special forensic circumstances. 相似文献
104.
J. M. Gómez A. J. Mu?oz-Pajares M. Abdelaziz J. Lorite F. Perfectti 《Annals of botany》2014,113(2):237-249
Background and Aims
How generalist plants diverge in response to pollinator selection without becoming specialized is still unknown. This study explores this question, focusing on the evolution of the pollination system in the pollination generalist Erysimum mediohispanicum (Brassicaceae).Methods
Pollinator assemblages were surveyed from 2001 to 2010 in 48 geo-referenced populations covering the entire geographic distribution of E. mediohispanicum. Bipartite modularity, a complex network tool, was used to find the pollination niche of each population. Evolution of the pollination niches and the correlated evolution of floral traits and pollination niches were explored using within-species comparative analyses.Key Results
Despite being generalists, the E. mediohispanicum populations studied can be classified into five pollination niches. The boundaries between niches were not sharp, the niches differing among them in the relative frequencies of the floral visitor functional groups. The absence of spatial autocorrelation and phylogenetic signal indicates that the niches were distributed in a phylogeographic mosaic. The ancestral E. mediohispanicum populations presumably belonged to the niche defined by a high number of beetle and ant visits. A correlated evolution was found between pollination niches and some floral traits, suggesting the existence of generalist pollination ecotypes.Conclusions
It is conjectured that the geographic variation in pollination niches has contributed to the observed floral divergence in E. mediohispanicum. The process mediating this floral divergence presumably has been adaptive wandering, but the adaptation to the local pollinator faunas has been not universal. The outcome is a landscape where a few populations locally adapted to their pollination environment (generalist pollination ecotypes) coexist with many populations where this local adaptation has failed and where the plant phenotype is not primarily shaped by pollinators. 相似文献105.
Moulay Abdelaziz El Alaoui Azeddine Ibrahimi Oussama Semlali Zineb Tarhda Melloul Marouane Alaoui Najwa Abdelmajid Soulaymani Elmostafa El Fahime 《Bioinformation》2014,10(1):33-38
The Δ9-Tetrahydrocannabinol (THCA) is the primary psychoactive compound of Cannabis Sativa. It is produced by Δ1-
Tetrahydrocannabinolic acid synthase (THCA) which catalyzes the oxidative cyclization of cannabigerolic acid (CBGA) the
precursor of the THCA. In this study, we were interested by the three dimensional structure of THCA synthase protein. Generation
of models were done by MODELLER v9.11 and homology modeling with Δ1-tetrahydrocannabinolic acid (THCA) synthase X ray
structure (PDB code 3VTE) on the basis of sequences retrieved from GenBank. Procheck, Errat, and Verify 3D tools were used to
verify the reliability of the six 3D models obtained, the overall quality factor and the Prosa Z-score were also used to check the
quality of the six modeled proteins. The RMSDs for C-alpha atoms, main-chain atoms, side-chain atoms and all atoms between the
modeled structures and the corresponding template ranged between 0.290 Å-1.252 Å, reflecting the good quality of the obtained
models. Our study of the CBGA-THCA synthase docking demonstrated that the active site pocket was successfully recognized
using computational approach. The interaction energy of CBGA computed in ‘fiber types’ proteins ranged between -4.1 95
kcal/mol and -5.95 kcal/mol whereas in the ‘drug type’ was about -7.02 kcal/mol to -7.16 kcal/mol, which maybe indicate the
important role played by the interaction energy of CBGA in the determination of the THCA level in Cannabis Sativa L. varieties.
Finally, we have proposed an experimental design in order to explore the binding energy source of ligand-enzyme in Cannabis
Sativa and the production level of the THCA in the absence of any information regarding the correlation between the enzyme
affinity and THCA level production. This report opens the doors to more studies predicting the binding site pocket with accuracy
from the perspective of the protein affinity and THCA level produced in Cannabis Sativa. 相似文献
106.
Dalia H. Abdelaziz Khaled Amr Amal O. Amer 《The international journal of biochemistry & cell biology》2010,42(6):789-791
Nlrc4 is a member of the Nod-like receptors (NLRs), a family of cytosolic receptors involved in sensing bacterial molecules. NLRs are a group of proteins containing spans of leucine-rich repeats that senses bacterial factors within the eukaryotic cytosol. The recognition of bacterial factors provokes the formation of the inflammasome complex which includes specific NLRs. The inflammasome is responsible for caspase-1 activation which leads to the cleavage and maturation of inflammatory cytokines such as IL-1β and IL-18. Nlrc4 was considered to be a devoted flagellin sensor in eukaryotic cells. However, studies using a variety of pathogens such as Salmonella, Legionella, Shigella and Pseudomonas at high bacterial burdens revealed that Nlrc4 can mediate caspase-1 activation independent of bacterial flagellin. On the other hand, new reports showed that Nlrc4 can restrict bacterial infection independently of caspase-1. Therefore, Nlrc4 maybe involved in sensing more than one bacterial molecule and may participate in several immune complexes. 相似文献
107.
108.
109.
Waste stabilization ponds are a simple, low-cost extensive process for treating wastewater, and well adapted to low socio-economic
conditions in developing countries where the microbial populations in these systems are not well characterized. The phylogenetic
bacterial community structure within a Tunisian wastewater stabilization plant treating domestic wastewater was assessed by
Terminal Restriction Fragment Length Polymorphism method targeting 16S rRNA genes and by the APLAUS+ software of the Microbial
Community Analysis (MiCA) web based tool. The dimeric enzymatic digestion with HaeIII and HinfI restriction enzymes revealed high bacterial diversity within the plant where 11 bacterial phyla were identified. The total
bacterial community structure includes bacteria catalysing nitrogen and phosphorus removal and bacteria involved in the sulfur
cycle. The bacterial community was characterized by the dominance of Proteobacteria which was the most populous phylum (60%) followed by the Actinobacteria (20%), the Firmicutes (10.3%), the Bacteroidetes (2.3%), the Nitrospira (2.2%). Minor bacterial phyla groups occupied smaller fractions such as Chloroflexi, Deferribacteres and Verrumicrobia. T-RFLP analysis revealed also that The Proteobacteria phylum was characterized by the dominance of bacteria of The Gammaproteobacteria class. 相似文献
110.
Amira A. Ghoneim Ahmed F. El-Farargy Sahar Abdelaziz 《Nucleosides, nucleotides & nucleic acids》2013,32(9):583-596
Direct preparation of 2-amino-5,6,7,8-tetrahydro-4-(4-methoxyphenyl)-7,7-dimethyl-5-oxo-4H-chromene-3-carbonitrile 2 and 1,2-diamino-1,4,5,6,7,8-hexahydro-4-(4-methoxyphenyl)-7,7-dimethyl-5-oxo-3-quinolinecarbonitrile 11, which were utilized as starting products for the synthesis of S-nucleoside analogues 10 and 15 and C-nucleoside analogues 12 and 13, is presented in the current study. The antibacterial and antifungal activities of these new compounds were evaluated. The structures of the new products were confirmed on the basis of elemental and spectral analysis results. 相似文献