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351.

Background:

Melon (Cucumis melo) allergy is one of the most common food allergies, characterized by oral allergy syndrome. To date, two allergen molecules, Cuc m 1 and Cuc m 2, have been fully characterized in melon pulp, but there are few reports about the molecular characteristics of Cuc m 3.

Methods:

The Cuc m 3 cDNA has been characterized by rapid amplification of cDNA ends (RACE), which revealed a 456 base-pair (bp) fragment encoding a 151-amino acid polypeptide with a predicted molecular mass of 16.97 kDa, and identified 79 and 178 bp untranslated sequences at the 5′ and 3´ ends, respectively.

Results:

In silico analysis showed strong similarities between Cuc m 3 and other plant pathogen-related protein 1s from cucumber, grape, bell pepper, and tomato.

Conclusion:

Here we report the identification and characterization of the Cuc m 3 cDNA, which will be utilized for further analyses of structural and allergenic features of this allergen. Key Words: Melon, allergen, Cuc m 3, plant pathogenesis-related protein 1  相似文献   
352.
A new efficient catalytic system was investigated for the epoxidation of various olefins by cis-dioxo-bis[2-(2′-hydroxyphenyl)-oxazolinato]molybdenum(VI), cis-[MoO2(phox)2], and TBHP as oxidizing agent. Using this system as catalyst for the oxidation of aliphatic substrates at 80 °C gives the epoxide as the sole product with yields up to 100% and turnover frequency up to 5000 h−1. The efficiency of the catalyst is strongly influenced by the nature of solvent, reaction time and temperature, and a significant increase in the epoxide yields is observed in higher temperatures and longer reaction times.  相似文献   
353.
Occluding artery disease causes a high demand for bioartificial replacement vessels. We investigated the combined use of biodegradable and creep‐free poly (1,3‐trimethylene carbonate) (PTMC) with smooth muscle cells (SMC) derived by biochemical or mechanical stimulation of adipose tissue‐derived stromal cells (ASC) to engineer bioartificial arteries. Biochemical induction of cultured ASC to SMC was done with TGF‐β1 for 7d. Phenotype and function were assessed by qRT‐PCR, immunodetection and collagen contraction assays. The influence of mechanical stimulation on non‐differentiated and pre‐differentiated ASC, loaded in porous tubular PTMC scaffolds, was assessed after culturing under pulsatile flow for 14d. Assays included qRT‐PCR, production of extracellular matrix and scanning electron microscopy. ASC adhesion and TGF‐β1‐driven differentiation to contractile SMC on PTMC did not differ from tissue culture polystyrene controls. Mesenchymal and SMC markers were increased compared to controls. Interestingly, pre‐differentiated ASC had only marginal higher contractility than controls. Moreover, in 3D PTMC scaffolds, mechanical stimulation yielded well‐aligned ASC‐derived SMC which deposited ECM. Under the same conditions, pre‐differentiated ASC‐derived SMC maintained their SMC phenotype. Our results show that mechanical stimulation can replace TGF‐β1 pre‐stimulation to generate SMC from ASC and that pre‐differentiated ASC keep their SMC phenotype with increased expression of SMC markers.  相似文献   
354.
BackgroundToday, a suitable vaccine has not yet been discovered to prevent Toxoplasma gondii infection. Therefore, prophylaxis can be suggested as the preferred approach to prevent toxoplasmosis. This study aims to evaluate the prophylactic effects of synthesized zinc nanoparticles (ZnNPs) using Lavandula angustifolia Vera., by microwave method on chronic toxoplasmosis in mice.MethodsBALB/c Mice orally administrated with ZnNPs the doses of 32.5, 75, 150 mg/kg/day for two weeks. On the 15th day, the mice were intraperitoneally infected with the Tehran strain of T. gondii (25 tissue cysts). The mean diameter and the numbers of brain tissue cysts, as well as the mRNA levels of inducible nitric oxide synthesize (iNOs), and interferon-gamma (IFN-γ) in mice of each experimental group were evaluated.ResultsThe synthesized ZnNPs represent a spherical form with a size ranging from 30 to 80 nm. The results revealed that oral administration of Zn NPs at the doses of 32.5 (p < 0.001) and 75 mg/kg/day (p < 0.001) for 14 days significantly reduced the mean number and diameter of the brain tissue cysts in tested mice. No T. gondii tissue cyst was observed after oral administration of Zn NPs at the doses of 150 mg/kg. Based on the results of Real-time PCR analysis, the expression level of IFN-γ and iNOs was significantly increased (p < 0.001) in mice treated with 32.5, 75, 150 mg/kg/day for two weeks.ConclusionThe obtained findings of the current investigation exhibit the significant prophylactic effects of ZnNPs against chronic toxoplasmosis in mice; so that oral administration of ZnNPs the doses 32.5, 75, 150 mg/kg reduced the parasite load and even completely controlled the infection in mice. The results show that the ZnNPs had strengthened the innate immune system which could be the reason for its strong prophylactic effects. However, further in vivo and clinical investigations are required to confirm these results as well as other possible mechanisms that can trigger these pharmacological properties.  相似文献   
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The purpose of this study was to investigate the effect of clomiphene citrate and human chorionic gonadotropin (HCG) on the structural changes, as well as the evaluation of the expression of cation channel sperm‐associated protein 1 (CatSper1), cation channel sperm‐associated protein 2 (CatSper2), luteinizing hormone/choriogonadotropin receptor (LHCGR), and steroidogenic factor 1 (SF1) genes in testicular tissue of rats. All rats divided into five groups as follows; G1 as the control group that received normal saline, G2 received olive oil, G3 received 100 IU/kg HCG, G4 received 5 mg/kg clomiphene citrate, and G5 received 5 mg/kg clomiphene citrate and 100 IU/kg HCG. At the end of the experiment period, Day 56, blood samples were taken and the serum was isolated. Then, histomorphometric analysis, hormonal assess, and real‐time polymerase chain reaction to measure the expression of CatSper1, CatSper2, LHCGR, and SF1 genes were performed. The results showed that the concentrations of testosterone, follicle‐stimulating hormone, and luteinizing hormone were decreased in the G4 group, whereas these parameters were increased in the G3 group. A comparison of the sperm quality indicated a significant reduction in the quality of sperm cells in the G4 group compared with other groups. The quality of sperm was significantly enhanced in the G3 and G5 groups in comparison with the G1 group. Also, our findings demonstrated that the expression of CatSper1, CatSper2, LHCGR, and SF1 genes were significantly elevated in the G3 group when compared with other experimental groups. According to the obtained results, it seems that clomiphene citrate reduces the process of spermatogenesis and the detrimental impacts of this compound would be neutralized by the administration of HCG.  相似文献   
358.
Monitoring of toxic trace elements for human blood has been of interest to researchers in the fields of environmental chemistry and medical science. The amount of blood toxic elements can reflect the disease state of the person or the environment where that person resides or works. Chronic, low-level exposure to toxic metals such as lead (Pb), cadmium (Cd), and mercury (Hg) is an increasing global problem. This study focuses on obtaining the usual value of Pb, Cd, and Hg in normal human blood. These elements were determined in 61 male and 40 female volunteers resident in Tehran (Iran). The subjects were non-drug abusers and aged 6-62 years old. Procedures were developed for the collection, storage, and preanalytical treatment of samples. The lead and cadmium were determined by graphite furnace atomic absorption spectrometry, and mercury was measured by cold vapor atomic absorption spectrometry technique. The blood levels of Pb, Cd, and Hg in normal volunteers living in Tehran were 123.75 +/- 56.42, 1.82 +/- 0.67, and 8.48 +/- 4.42 microg/L. There was no significant gender-related difference in blood Cd and Hg concentrations (p < 0.06 and p < 0.41). However, the results indicated significantly higher content of Pb in blood of males compared to females (138.11 +/- 65.43 and 101.84 +/- 51.38 microg/L, respectively, p < 0.05).  相似文献   
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Molecular Biology Reports - Multiple sclerosis (MS) is an autoimmune-type inflammatory disorder in human central nervous system. Recombinant interferon beta (IFN-β) decreases the number of...  相似文献   
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