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61.
AbstractA study was undertaken to compare the patterns of spatial variability, epiphytic percentage cover, and distribution of epiphytic fauna and flora between the two adjacent seagrasses Cymodocea nodosa and the invasive species Halophila stipulucea. Samples were taken at six stations separated by 600?m and exposed to different current conditions. The stations G2 and G5 were affected by a high current tide, while G4 was directly exposed to the northern marine currents. The station G3 was situated in the middle of a Posidonia oceanica bed and was less exposed to hydrodynamism, whereas the other stations were relatively protected. Results indicate that for both H. stipulacea and C. nodosa, shoot density and epiphytic cover biomass decreased when exposed to high levels of hydrodynamic activity. In terms of epiphytic leaf assemblages, our results showed significant differences for the two host plants in their mean cover and for the six stations at the largest and smallest spatial scale. Our observations highlight the dominance of Rhodophyta and the low number of epiphytic species and the epiphytic cover on H. stipulacea compared to C. nodosa. In addition, results indicate the absence of two taxa Hydrozoans and Annelida in the epiphytic assemblage of H. stipulacea leaves. 相似文献
62.
Azadeh Mohammadi-Farsani Ali Jahanian-Najafabadi Mehryar Habibi-Roudkenar Majid Golkar Mohammad Ali Shokrgozar Hossein KhanAhmad Maryam Golshani Samira Valiyari Saeid Bouzari 《International journal of peptide research and therapeutics》2018,24(3):369-375
Targeted drug delivery is an attractive field in cancer studies. In this study, a novel fusion protein consisting of Shiga toxin A subunit and NGR peptide has been constructed. The cytotoxic Shiga toxin A subunit has the ability to kill cancer cells while NGR is a well-known peptide that targets the whole molecule to cancer cells. Two forms of this novel fusion protein, one without linker (A-NGR) and one with linker (A-GGGGS-NGR) were studied. 3D structure prediction of the two forms carried out by I-TASSER and their validation and analysis were performed by ProSA web and RAMPAGE. Results showed that A-NGR is a better model than the one with linker. A-NGR was constructed by PCR method and cloned in pBAD/gIII A vector. Then, it was successfully expressed in Escherichia coli by induction with arabinose and subsequently purified by affinity chromatography under denaturing condition. Ultimately, the cytotoxic effect of the purified protein was evaluated on U937 cancer cells and MRC-5 normal cells by MTT assay. Conclusively, the fusion protein was successfully cloned and expressed and evaluated for its cytotoxic effects. The IC50 value of A-NGR fusion protein for U937 cell was about 26.86 µg/ml while no cytotoxic effect was observed on MRC-5 cells. Therefore, considering the promising cytotoxic effects of the fusion protein, further in vitro evaluations of this fusion protein on different cell lines are underway. 相似文献
63.
H. M. Kalaji A. Rastogi M. Živčák M. Brestic A. Daszkowska-Golec K. Sitko K. Y. Alsharafa R. Lotfi P. Stypiński I. A. Samborska M. D. Cetner 《Photosynthetica》2018,56(3):953-961
The study examined photosynthetic efficiency of two barley landraces (cvs. Arabi Abiad and Arabi Aswad) through a prompt fluorescence technique under influence of 14 different abiotic stress factors. The difference in the behavior of photosynthetic parameters under the same stress factor in–between cv. Arabi Abiad and cv. Arabi Aswad indicated different mechanisms of tolerance and strategies for the conversion of light energy into chemical energy for both the landraces. This study confirmed the suitability of some chlorophyll fluorescence parameters as reliable biomarkers for screening the plants at the level of photosynthetic apparatus. 相似文献
64.
Helen Louise May-Simera Qin Wan Balendu Shekhar Jha Juliet Hartford Vladimir Khristov Roba Dejene Justin Chang Sarita Patnaik Quanlong Lu Poulomi Banerjee Jason Silver Christine Insinna-Kettenhofen Dishita Patel Mostafa Lotfi May Malicdan Nathan Hotaling Arvydas Maminishkis Rupa Sridharan Kapil Bharti 《Cell reports》2018,22(1):189-205
65.
Arsalan Khalili-Moghadam Alireza Saboori Alireza Nemati Azadeh Zahedi Golpayegani 《Biologia》2018,73(10):977-986
In this paper, we redescribe Gaeolaelaps deinos (Zeman 1982) based on morphological characters of female and male specimens collected from nests of Lasius sp. (Hymenoptera: Formicidae) Khuzestan and Chaharmahal va Bakhtiari Provinces, Iran, and based on its holotype photos. We also present an identification key for Gaeolaelaps aculeifer-like species group from Iran. 相似文献
66.
67.
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
68.
Hadi Mozafari Zohreh Rahimi Azadeh Heidarpour Mahsa Fallahi Adraiana Muniz 《Molecular biology reports》2009,36(8):2361-2364
It has been suggested that the allele frequency of thrombophilic mutations is affected by glucose-6-phosphate dehydrogenase
(G6PD) deficiency. The prevalence of thrombophilic mutations were studied in sixty G6PD deficient individuals including 57
males and three females with the mean age of 15 ± 3.08 and 110 age and sex matched healthy individuals consisted of 95 males and 15 females with
the mean age of 16.19 ± 2.17 from the Kermanshah Province of Iran. Using a combination of PCR-RFLP technique, single strand
conformation polymorphism (SSCP) analysis and DNA sequencing polymorphic G6PD mutations were identified. The factor V Leiden,
prothrombin G20210A and methylenetetrahydrofolate reductase (MTHFR) C677T were detected by PCR-RFLP method using MnlI, HindIII
and HinfI restriction enzymes, respectively. Three mutations, G6PD Mediterranean, G6PD Chatham and G6PD Cosenza were identified
in 60 G6PD deficient individuals with highest prevalence of G6PD Mediterranean (91.6%). In G6PD deficient individuals the
prevalence of factor V Leiden tended to be higher (5%) compared to healthy individuals (2.7%). The prevalence of prothrombin
G20210A mutation in G6PD deficient individuals was 1.7%. However, in normal subjects the prevalence of this mutation was 2.7%.
The frequency of T allele in G6PD deficient individuals were insignificantly higher (29.16%) than those in healthy individuals
(26.8%). Our finding indicates that the prevalence of factor V Leiden, prothrombin G20210A and MTHFR C677T in G6PD deficient
individuals is not statistically different compared to normal subjects and G6PD deficiency is not associated with these thrombophilic
mutations in Western Iran. 相似文献
69.
Cyclooxygenase-2 (Cox-2) is a key enzyme in the conversion of arachidonic acid to prostaglandins that has been shown to have
a particular importance in the progression of several malignancies including nasopharyngeal carcinoma (NPC). In the current
report, we designed a case-controlled study to evaluate the susceptibility and prognostic implications of the functional −765
G > C genetic variation in NPC. A PCR and restriction fragment length polymorphism analysis was used to determine the polymorphism
in a Tunisian population of patients with NPC (n = 180) and in healthy control subjects (n = 169). A higher risk for NPC was observed for carriers of COX-2 −765 C allele (OR = 1.76; P = 0.01). This association remains significant after adjustments for age and sex (OR = 1.89; P = 0.008). Regarding prognostic indicators, a significant association was found between −765 C allele carriers and the presence
of lymph node metastasis (OR = 2.28; P = 0.01), as well as, with tumor stage (OR = 2.73; P = 0.03). This is the first report on the studies of COX-2 SNPs in NPC and our data suggest that this genetic variant may
play a role in mediating susceptibility to NPC, as well as, in neoplastic progression, a finding which further supports the
involvement of COX-2 in NPC etiology.
Hela Ben Nasr and Karim Chahed contributed equally to the study. 相似文献
70.
Sfar S Abid A Mahfoudh W Ouragini H Ouechtati F Abdelhak S Chouchane L 《Molecular biology reports》2009,36(4):661-667
Hereditary multiple exostoses (HME) is an autosomal dominant orthopaedic disorder most frequently caused by mutations in the
EXT1 gene. The aim of the present study is to determine the underlying molecular defect of HME in two multigenerational Tunisian
families with 21 affected members and to examine the degree of intrafamilial variability. Linkage analysis was performed using
three microsatellite markers encompassing the EXT1 locus and mutation screening was carried out by direct sequencing. In family 1, evidence for linkage to EXT1 was obtained on the basis of a maximum LOD score of 4.26 at θ = 0.00 with D8S1694 marker. Sequencing of the EXT1 revealed a heterozygous G > T transversion (c.1019G>T) in exon 2, leading to a missense mutation at the codon 340 (p.Arg340Leu).
In family 2 we identified a novel heterozygous 1 bp deletion in the exon 1 (c.529_531delA) leading to a premature codon stop
and truncated EXT1 protein expression (p.Lys177LysfsX15). This mutation was associated with the evidence of an intrafamilial
clinical variability and considered to be a novel disease-causing mutation in the EXT1 gene. These findings provide additional support for the involvement of EXT1 gene in the HME disease. 相似文献