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81.
We studied the role of methyl salicylate as an important part of volatile blends in searching behaviour of the predatory mite, Phytoseiulus persimilis (Athias-Henriot). We showed that Methyl Salicylate (MeSa) attracted the predatory mites (1 h starved) in a dose range of 0.02–20?μg. The highest attraction was recorded at the dose of 0.2?μg. The dose of 0.002?μg was considered under the detection level of the predator. P. persimilis could not detect the extra amount of MeSa (100 and 200?μg). The probable effect of starvation period on the predator response is discussed.  相似文献   
82.
BACKGROUND: Several genes coding for different cytokines may affect host susceptibility to tuberculosis. METHODS: In the present study, the allele and genotype frequencies of a number polymorphic genes coding for cytokines or cytokine receptors were investigated in Iranian patients with pulmonary tuberculosis (PTB). RESULTS: From the IL-1 cluster, a positive, significant difference was found at position -889, where the T/T genotype was over represented in PTB patients (p = 0.01); a positive, significant increase was found in the IL1R PstI 1970 C/C genotype, where the C allele was over represented in the PTB patients (p = 0.01). A significant negative association at codon 10 TGF-beta, T allele, was shown in our patients and the C allele and C/C genotype were over represented in the PTB patients (P<0.005). For TNF-alpha at position -238, we found a negative association for the G/A genotype and a positive association for the G/G genotype (p = 0.0009). Significant negative associations at position -590 IL-4, T allele and the T/T genotype were shown in our patients (p = 0.0007); also, the C allele and T/C genotype were significantly increased in our patients (P<0.05). With IL-6 at -174, G/G increased and G/C decreased significantly in the patients (P<0.005). CONCLUSION: Pro-inflammatory cytokines such as TNF-alpha and TGF-beta seem to be decreased, and IL-6 increased in PTB patients.  相似文献   
83.

Background

C-terminal tensin-like protein (Cten) is a focal adhesion protein originally identified as a tumor suppressor in prostate cancer. It has since been found to be overexpressed and function as an oncogene in numerous other cancers, but the expression status of Cten in melanoma is still unknown.

Methods

Using tissue microarrays containing 562 melanocytic lesions, we evaluated Cten protein expression by immunohistochemistry. The association between Cten expression and patient survival was examined using Kaplan-Meier survival analysis, and univariate and multivariate Cox regression analyses were used to estimate the crude and adjusted hazard ratios.

Results

Strong Cten expression was detected in 7%, 24%, 41%, and 46% of normal nevi, dysplastic nevi, primary melanoma, and metastatic melanoma samples, respectively, and Cten expression was found to be significantly higher in dysplastic nevi compared to normal nevi (P = 0.046), and in primary melanoma compared to dysplastic nevi (P = 0.003), but no difference was observed between metastatic and primary melanoma. Cten staining also correlated with AJCC stages (P = 0.015) and primary tumor thickness (P = 0.002), with Cten expression being induced in the transition from thin (<1mm) to thick (≥1mm) melanomas. Strong Cten expression was significantly associated with a worse 5-year overall (P = 0.008) and disease-specific survival (P = 0.004) for primary melanoma patients, and multivariate Cox regression analysis revealed that Cten expression was an independent prognostic marker for these patients (P = 0.038 for overall survival; P = 0.021 for disease-specific survival).

Conclusion

Our findings indicate that induction of Cten protein expression is a relatively early event in melanoma progression, and that Cten has the potential to serve as a prognostic marker for primary melanoma patients.  相似文献   
84.
Abstract

In mammalian cell culture technology, viral contamination is one of the main challenges; and, so far, various strategies have been taken to remove or inactivate viruses in the cell-line production process. The suitability and feasibility of each method are determined by different factors including effectiveness in target virus inactivation, maintaining recombinant protein stability, easiness—in terms of the process condition, cost-effectiveness, and eco-friendliness. In this research, Taguchi design-of-experiments (DOE) methodology was used to optimize a non-detergent viral inactivation method via considering four factors of temperature, time, pH, and alcohol concentration in an unbiased (orthogonal) fashion with low influence of nuisance factors. Herpes Simplex Virus-1 (HSV1) and Vero cell-line were used as models for enveloped viruses and cell-line, respectively. Examining the cytopathic effects (CPE) in different dilutions showed that pH (4), alcohol (15%), time (120?min), and temperature (25?°C) were the optimal points for viral inactivation. Evaluating the significance of each parameter in the HSV-1 inactivation using Taguchi and ANOVA analyses, the contributions of pH, alcohol, temperature and time were 56.5%, 19.2%, 12%, and 12%, respectively. Examining the impact of the optimal viral treatment condition on the stability of model recombinant protein-recombinant human erythropoietin, no destabilization was detected.  相似文献   
85.
Reports on the isolation of mesenchymal stromal cells (MSCs) from granulocyte colony stimulating factor mobilized peripheral blood (G-CSF-mobilized PB) using regular culturing techniques are controversial. Enrichment techniques such as CD133 isolation have increased the success rates. CD271 is a wellknown marker for enrichment of MSCs from bone marrow (BM). In the present study, we aimed to find out whether CD271 enrichment can help isolation of MSCs from G-CSF-mobiiized PB. Five G-CSF-mobilized PB samples were collected from the remnant parts of the bags used for BM transplantation. Five BM samples were used as the control. Mononuclear cells (MNCs) from both resources were collected and underwent magnetic sorting for CD271-positive cells. The isolated cells were cultured, undergoing flowcytometry and differentiation assays to determine if they fulfill MSCs characteristics. CD271-positive portion of G-CSF-mobilized PB did not yield any cell outgrowth but the BM counterpart could successfully form MSC colonies. Although the percentage of CD271+ cells showed no difference between BM-MNCs and G-CSF-mobilized PB-MNCs, hematopoietic markers such as CD45, CD34 and CD133 composed a higher percentage of CD271-positive cells in the G-CSF-tnobiiized PB group. Results obtained indicated that CD271 enrichment does not help isolation of MSCs from G-CSF-mobilized PB. In this source, almost all of the CD271+ cells are from hematopoietic origin and the frequency of MSCs is so low that possibly during the process of cell isolation most of them are lost and the isolation fails.  相似文献   
86.
87.
Membrane fusion for morbillivirus cell entry relies on critical interactions between the viral fusion (F) and attachment (H) envelope glycoproteins. Through extensive mutagenesis of an F cavity recently proposed to contribute to F''s interaction with the H protein, we identified two neighboring hydrophobic residues responsible for severe F-to-H binding and fusion-triggering deficiencies when they were mutated in combination. Since both residues reside on one side of the F cavity, the data suggest that H binds the F globular head domain sideways.  相似文献   
88.
89.
A simple bio-conjugation procedure to surround a single horseradish peroxidase (HRP) enzyme molecule with dendritic polyester macromolecules (polyester-32-hydroxyl-1-carboxyl bis-MPA dendron, generation 5) was proposed. The characterization of resultant nanoparticles entitled HRP dendrozyme, was performed by transmission electron microscopy, dynamic light scattering, gel permeation chromatography and Fourier transform infrared spectroscopy. The results showed that HRP nanoparticles were spherical in shape and have an average size of 14 ± 2 nm in diameter. Furthermore, bio-conformational characterization of HRP dendrozyme was performed by means of circular dichroism and fluorescence spectroscopy to evaluate the secondary and tertiary structure changes after enzyme modification. These investigations revealed that protein conformation had small changes (in secondary and tertiary structures) after bio-conjugation. We also reported here that dendritic modification did not significantly affect the kinetic parameters of free HRP. The stabilization of HRP with dendron macromolecules as single enzyme nanoparticles resulted in improvement of half-life over 70 days storage at 4 °C as well as its tolerance under different elevated temperatures up to 80 °C and in the presence of organic solvents for 15 min. These significant results promise extensive applications of HRP particularly in harsh environmental conditions.  相似文献   
90.
Four species of the genus Berberis L. have been reported from different regions, including Khorassan provinces. In this article, a revision of this genus in Khorassan provinces is presented. For better validation of the results, morphological, palynological, chromosomal and molecular studies were conducted on specimens collected from Khorassan provinces and preserved in FUMH and TARI herbaria. Morphological study resulted in recognition of three species of Berberis, from which two species are new records for Khorassan. Four unknown new taxa with new morphological characters were also identified, but left for further analysis because of the high percentage of polyploidy and hybridization in this genus. In order to analyze morphological data, 35 OTUs were provided and scored using the distance method and PCoA. The shape and size of pollen grains were nearly equal in the examined taxa, and there were no obvious differences between them. Chromosomal examination indicated tetraploidy (2n = 4x = 56) in all of the studied taxa. Molecular studies were accomplished by RAPD and sequencing of the ITS region to construct a framework of relationships between the taxa. Molecular studies emphasized the difference in the four unknown taxa from others. The total evidence indicates that Berberis L. shows a high percentage of polyploidy and hybridization.  相似文献   
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