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201.
Peptic ulcer disease (PUD) is a common illness, affecting a considerable number of people world-wide, and its occurrence can be influenced by environmental and genetic factors. Heat shock proteins (HSPs) function mostly as molecular chaperones, and are induced by various stresses. The A to G transition at position 1267 of the HSPA1B gene was shown to correlate with changes in the level of HSPA mRNA expression. Here, the relation between A1267G polymorphism of the HSPA1B gene and risk of peptic ulcer in the Iranian population was evaluated. One hundred subjects, who underwent gastroscopy, took part in the study. DNA samples extracted from the biopsy tissues were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). After gastroscopy, peptic ulcer was diagnosed for 50 patients; among them the distribution of AA/AB/BB genotypes was 10, 88, and 2%, respectively. As for the other 50 subjects (without peptic ulcer) included in the control group, the AA/AB/BB genotypes were identified as 40, 52 and 8%, respectively. A significant association was found between the HSPA1B genotype and peptic ulcer (6.76 OR; 95% CI, 2.26–20.2; p = 0.0006). Thus, the HSPA1B A1267G polymorphism may be a marker of susceptibility to peptic ulcer. 相似文献
202.
Objective The glutathione S-transferases (GSTs) are a superfamily of proteins that participates in detoxification. The GSTs were dividing into several
classes including omega (GSTO), mu (GSTM) and theta (GSTT) classes. In human GSTO2, GSTM1, and GSTT1 are polymorphic. In order to study whether GSTO2, GSTM1, and GSTT1 polymorphisms are associated with increased gastric cancer risk in Iranian patients, the present case–control study was done.
Methods Genomic DNA was extracted from peripheral blood of 67 gastric cancer patients and 134 control subjects. The genotyping was
performed using PCR-based method. The possible association of gastric cancer with the GSTO2 N142D polymorphism was estimated with assuming additive, dominant, and recessive effect of the variant 142D allele. To investigate whether profiles of GST genotypes are associated with the risk of gastric cancer, we used unconditional
logistic regression analysis. Results The GSTO2 142D allele in additive, dominant and recessive models was not associated with the risk. Because GSTM1, GSTT1, and GSTO2 genes belong to low-penetrance genes which might be involved in the carcinogenesis, patients and controls without family
of cancer in first-degree relatives were also analyzes separately. To investigate whether profiles of GST genotypes are associated
with the risk of gastric cancer, we used unconditional logistic regression analysis with GSTM1, GSTT1, and GSTO2 genotypes as predictor factors. The GSTO2 DD genotype was associated with decreased risk as compared to GSTO2 NN genotype (OR = 0.21, 95% CI: 0.05–0.92, P = 0.038). Conclusions Present findings show that GSTO2 DD genotype decreases the risk of gastric cancer in individuals without history of cancer in their first-degree relatives. 相似文献
203.
204.
Adaptive sampling designs are becoming increasingly popular in environmental science, particularly for surveying rare and
aggregated populations. An adaptive sample is one in which the survey design is modified, or adapted, in some way on the basis
of information gained during the survey. There are many different adaptive survey designs that can be used to estimate animal
and plant abundance. In adaptive cluster sampling, additional sample effort is allocated during the survey to the immediate
neighborhood in which the species is found. In adaptive stratified sampling, additional sample effort is allocated during
the survey to strata of high abundance. The appealing feature of these adaptive designs is that the field biologist gets to
do what innately seems sensible when working with rare and aggregated populations—field effort is targeted around where the
species is observed in the first wave of the survey. However, there are logistical challenges of applying this principle of
targeted field effort while remaining in the framework of probability-based sampling. We propose a simplified adaptive survey
design that incorporates both targeting field effort and being logistically feasible. We show with a case study population
of rockfish that complete allocation stratified sampling is a very efficient design. 相似文献
205.
Abdoulreza Agheli Mansour Seyed Latif Mousavi Iraj Rasooli Shahram Nazarian Jafar Amani Nima Farhadi 《Biologicals》2010,38(2):260-264
Botulinum neurotoxins (BoNTs) inhibit neurotransmitter release from peripheral cholinergic synapses. BoNTs consist of a toxifying light chain and a heavy chain (HC) linked through a disulfide bond. In the present study we explored the immunogenicity and protective capability of the most effective part corresponding to 1163-1256 residues of botulinum type E neurotoxin HC gene. DNA encoding the 93 C-terminal amino acid of HC residues was synthesized with optimal codon usage for expression. These DNA fragments were ligated into a pLivSelect vector and subcloned into expression vector pET32a. Recombinant plasmids were then transformed into Escherichia coli strain BL21 DE3. The recombinant protein was purified by nickel affinity gel column chromatography. The HC1163-1256 was identified by antibodies raised against BoNT/E. HC1163-1256 was shown to bind with synaptotagmin and gangliosides, indicating that the expressed and purified HC1163-1256 protein retains a functionally active conformation. The immunization with recombinant protein induced a protection level in mice. The immunization with 2 μg of the recombinant protein induced a significant protection level in mice. In conclusion, availability of the recombinant protein provides an effective system to study the biochemical and physical interactions involved during BoNT binding to nerve cells and protection against its toxicity. 相似文献
206.
Elucidation of the structure of the ribosome has stimulated numerous proposals for the roles of specific rRNA elements, including the universally conserved helix 69 (H69) of 23S rRNA, which forms intersubunit bridge B2a and contacts the D stems of A- and P-site tRNAs. H69 has been proposed to be involved not only in subunit association and tRNA binding but also in initiation, translocation, translational accuracy, the peptidyl transferase reaction, and ribosome recycling. Consistent with such proposals, deletion of H69 confers a dominant lethal phenotype. Remarkably, in vitro assays show that affinity-purified Deltah69 ribosomes have normal translational accuracy, synthesize a full-length protein from a natural mRNA template, and support EF-G-dependent translocation at wild-type rates. However, Deltah69 50S subunits are unable to associate with 30S subunits in the absence of tRNA, are defective in RF1-catalyzed peptide release, and can be recycled in the absence of RRF. 相似文献
207.
Several polymorphisms in the XRCC5 (X-ray repair cross-complementing 5; OMIM: 194364) were reported. Polymorphism of variable number of tandem repeats (VNTR) in the promoter region of XRCC5 (rs6147172) was reported. The main aim of the present study is to introduce the high resolution melting analysis (HRMA) method for genotyping of the polymorphism of XRCC5 VNTR. Genotypes of XRCC5 VNTR were determined by HRMA and conventional PCR method, and confirmed by DNA sequencing. The results for genotyping using HRMA and conventional PCR showed 100% concordance. All genotypes of the XRCC5 VNTR polymorphism could be accurately detected by HRMA. 相似文献
208.
Yang Z. De Marinis Albert Salehi Caroline E. Ward Quan Zhang Fernando Abdulkader Martin Bengtsson Orit Braha Matthias Braun Reshma Ramracheya Stefan Amisten Abdella M. Habib Yusuke Moritoh Enming Zhang Frank Reimann Anders H. Rosengren Tadao Shibasaki Fiona Gribble Erik Renström Susumu Seino Lena Eliasson Patrik Rorsman 《Cell metabolism》2010,11(6):543-553
209.
Mehnoosh Ashja-Arvan Moein Dehbashi Asma Eslami Hossein Salehi Mahdiyeh Yoosefi Mazdak Ganjalikhani-Hakemi 《Journal of cellular physiology》2020,235(11):8736-8746
Adipose-derived stem cells (ADSCs) are a subset of mesenchymal stem cells that their therapeutic effects in various diseases make them an interesting tool in cell therapy. In the current study, we aimed to overexpress interferon-β (IFN-β) and leukemia inhibitory factor (LIF) cytokines in human ADSCs to evaluate the impact of this overexpression on human ADSCs properties. Here, we designed a construct containing IFN-β and LIF and then, transduced human adipose-derived stem cells (hADSCs) by this construct via a lentiviral vector (PCDH-513B). We assessed the ability of long-term expression of the transgene in transduced cells by western blot analysis and enzyme-linked immunosorbent assay techniques on Days 15, 45, and 75 after transduction. For the evaluation of stem cell properties, flow cytometry and differentiation assays were performed. Finally, the MTT assay was done to assess the proliferation of transduced cells compares to controls. Our results showed high-efficiency transduction with highest expression rates on Day 75 after transduction which were 70 pg/ml for IFN-β and 77.9 pg/ml for LIF in comparison with 25.60 pg/ml and 27.63 pg/ml, respectively, in untransduced cells (p = .0001). Also, transduced cells expressed a high level of ADSCs surface markers and successfully differentiated into adipocytes, chondrocytes, neural cells, and osteocytes besides the preservation rate of proliferation near untreated cells (p = .88). All in all, we successfully constructed an hADSC population stably overexpressed IFN-β and LIF cytokines. Considering the IFN-β and LIF anti-inflammatory and neuroprotective effects as well as immune-regulatory properties of hADSCs, the obtained cells of this study could be subjected for further evaluations in experimental autoimmune encephalomyelitis mice model. 相似文献
210.
Kiarash Jamshidi Goharrizi Farzaneh Amirmahani Fatemeh Salehi 《Physiologia plantarum》2020,168(4):973-989
In this study, 7-month-old UCB-1, Badami, Ghazvini and Kale-Ghouchi pistachio rootstocks were exposed to control, drought, salinity and drought + salinity environments for 60 d. Total chlorophyll and total carotenoid contents decreased in all cultivars under drought, salinity and drought + salinity stresses. Under drought and salinity stresses, alone or in combination, Na+ and Cl− ions increased in all four pistachio rootstocks, while K+ ion decreased only in Ghazvini and Kaleh-Ghouchi cultivars. The enzyme activities of ascorbate peroxidase, polyphenol oxidase, catalase and guaiacol peroxidase increased in all cultivars when subjected to all three stresses with the exception of the ascorbate peroxidase activity in Kale-Ghouchi cultivar during drought stress. Oxidative stress parameters including electrolyte leakage, malondialdehyde, other aldehydes and hydrogen peroxide increased under all three stress conditions in all genotypes. The content of proline, total free amino acids and total soluble carbohydrates were enhanced under drought, salinity and drought + salinity stresses, whereas the protein content decreased in all pistachio rootstocks. In all evaluated traits, except for the K+ ion content and APX activity, the highest impacts was seen for drought + salinity > salinity > drought stresses, respectively. For the first time, we have proven that K+ ion content has a positive correlation with the ascorbate peroxidase, polyphenol oxidase, catalase and guaiacol peroxidase enzymes activities under drought + salinity stress. Finally, based on the bi-plot and cluster analyses, we have selected the UCB-1 > Badami > Ghazvini > Kale-Ghouchi cultivars as the most tolerant pistachio rootstocks under drought + salinity stress, respectively. 相似文献