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Iran is one of several countries that has regions of high dose natural ionizing radiation. Two well-known villages in the suburb of Ramsar Town in the Caspian Sea strip, Taleshmahaleh and Chaparsar, have background radiation that is 13 times higher than normal. This radiation is the result of Radium 226 and Radon gas both of which are highly water soluble. While people living in these regions do not suffer from any major health problems, we decided to study the their immune responses to infection and inflammation in order to determine if their habitat affects their immune defense mechanisms as a way of compensating for their exposure to high dose environmental ionizing radiation. Our results showed that the total serum antioxidant level in the exposed people was significantly lower than the individuals not exposed to high dose natural ionizing radiation. The exposed individuals also had higher lymphocyte-induced IL-4 and IL-10 production, and lower IL-2 and IFN-gamma production. In addition, neutrophil NBT, phagocytosis, and locomotion were higher in the exposed group. In contrast, lymphocyte proliferation in response to PHA was unaffected. We conclude that the immune system of individuals exposed to high dose ionizing radiation has adapted to its environment by shifting from a Type 1 to a Type 2 response to promote anti-inflammation. This may be because inflammatory Type 1 responses generate more free radicals than Type 2 responses, in addition to the free radicals generated as a result of high environmental radiation. Thus, the serum total antioxidant level in the exposed residents was lower than the unexposed group.  相似文献   
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This research was conducted to investigate the physico-mechanical characteristics of the EC-based coating membranes plasticized with two informal ingredients of vitamin resources, cholecalciferol and alpha-tocopherol, with respect to the commercial plasticizer DBS. Proceeding the experiment, free thin polymer sheetings of the sample formulations, incorporating incremental weight percents of the individual plasticizers were prepared employing a revised casting method of delayed solvent evaporation whereby similar flat specimens of standard dimensions were subjected to tensile loadings and extensions. The data were analyzed through the known equations of membrane theory in spherical subjects considering the complete symmetry of assumingly spherical pellets and/or granules. The relative tensile parameters of the experimental and commercial plasticizers in the resilient region were also estimated to fairly decide on a moderate explanation of a strong, hard, and tough structure among the specimens. The results implied the great compatibility of the oily soluble vitamins in EC networks projecting higher factors of safety and greater ultimate strength, toughness, and young coefficient of the formulations compared to the specimens plasticized with the commercial DBS within a concentration range of 40-50% (w/w) of the polymer solids. alpha-Tocopherol represented supremacy over colecalciferol to result in relatively a 2-fold (and practically a 4-fold with respect to DBS) greater increase in the modulus of resilience. The vitamin compounds and in essential alpha-tocopherol, in consequence, can properly be applied at concentrations of 40-50% (w/w) as efficient plasticizers to provide a greater protection of the structure against sudden fractures of dynamic and continuously increasing environmental and biological stresses.  相似文献   
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β-Thalassemia (thal) is one of the most common genetic disorders in Iran and other countries. Getting information on the distribution of mutations in different ethnic groups of Iran is of fundamental importance for the purpose of health planning and prenatal diagnosis programs. One hundred and thirty chromosomes from 65 unrelated homozygous β-thal patients were investigated for β‐globin gene mutations by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). The most common mutations of the Mediterranean region were examined in this study. Our results showed that the frameshift codons (FSC) 36/37 (–T) mutation, with a frequency of 33.8%, is the most common mutation in Lorestan Province. The other most frequent mutations were of the Mediterranean type and consisted of IVS-II-1 (G?→A), IVS-I-110 (G?→A), FSC 8/9 (+G) and IVS-I-5 (G?→C) with frequencies of 27.7, 11.5, 10.8 and 4.5%, respectively. The less frequent alleles, IVS-II-745 (C?→G), FSC 5 (–CT), IVS-I (25 bp deletion) and FSC 44 (–C) accounted for only 3.9% of the mutations. The unknown alleles comprised 7.7% of the mutations. These data showed that the spectrum of mutations found in Lorestan Province was different from those reported from other thalassemic regions of Iran and also of some neighboring countries.  相似文献   
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Objectives

The contamination of soils with heavy metals is a grave environmental problem. Among the heavy metals, Cadmium (Cd) is regarded as one of the most toxic trace elements and environmental pollutants. The aim of this research is investigation of phytoremediation ability of Datura stramonium L. for Cadmium (Cd) and also, the enhancing effect of EDTA (ethylenediamine tetraacetic acid), indole-3-acetic acid (IAA) and kinetin (KN) on the uptake of Cd.

Methods

Four levels of cadmium (0, 75, 150 and 225 mg kg-1) and different enhancers including EDTA (0, 3, 6, 12 mmol kg-1), IAA, and kinetin (0, 1, 10, 100 mg L-1) were used as the experimental groups. Analysis of Cd in soil and plant materials was carried out using an atomic absorption spectrophotometer. The bioconcentration factor, translocation factor, protein content and enzymatic activity were also measured.

Results

The results showed that D. stramonium was a Cd accumulator plant with the TF of 1.12. Accumulation ability was increased with the application of the chelating agent and plant hormones; EDTA was found to be more effective in the enhancement of phytoremediation than others. Application of EDTA and hormones reduced the negative effects of Cd by means of increasing the total protein content and peroxidase activity. The total protein content in the leaves of D. stramonium, which had been treated with Cd/EDTA, Cd/KN and Cd/IAA, was increased 2.24, 3.59 and 3.41 times more than that in the Cd treated group, respectively. The highest peroxidase (POX) activity was determined in the group treated by 150-Cd +100-IAA (0.060 unit/mg protein).

Conclusion

It could be concluded that D. stramonium is a Cd-accumultor plant with phytoremediation potency. This study also demonstrated that EDTA and plant hormones (IAA and Kinetin) could be regarded as good strategies for increasing the phytoremediation ability of D. stramonium.
  相似文献   
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Hepatitis B virus (HBV) infection is one of the clinical dilemmas in chronic liver diseases. MicroRNAs (miRNAs) are small noncoding RNA molecules that play an important role in the pathogenesis of liver diseases and single nucleotide polymorphisms (SNPs) in miRNA genes affect the clinical course of HBV infection. Previous studies have shown that miRNA-146a rs2910164 polymorphism can be associated with the pathogenesis of liver diseases such as hepatocellular carcinoma. The present study investigated the association between miRNA-146a rs2910164 polymorphism and susceptibility to HBV infection in an Iranian population. The study comprised 266 patients with chronic HBV infection, 172 patients with spontaneous viral clearance (SVC) after acute HBV infection, and 266 healthy control adjusted for sex and age. The genotyping of the miRNA-146a rs2910164 polymorphism was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Our data revealed that GG genotype and G allele of miRNA-146a rs2910164 SNP is dominated (P < 0.001) in patients with chronic HBV infection (Odds ratio [OR] = 3.92; 95% confidence interval [CI] = 2.1-7.32). miRNA-146a rs2910164 polymorphism showed a statistically significant association (P < 0.001) between CC genotype and allele C with SVC (OR = 2.92; 95% CI = 1.56-546). Our findings suggest miRNA-146a SNP (C/G) in our population may be associated with the susceptibility to HBV infection and CC genotype is associated with SVC. Also, the GG genotype and G allele at miRNA-146a rs2910164 is associated with chronic HBV infection in our population.  相似文献   
7.
OBJECTIVES: The aim of this study was to investigate the caries and fluorosis prevalence among 6- and 9-year-old students in three communities in Iran with varying urbanization and fluoride in piped water. METHODS: Data were obtained from 523 dental examinations of 6- and 9-year olds in an upper middle class district in Teheran (T) (0.3 mg F/l), the city of Semnan (S) (1.3 mg F/l), and the village Dibaj (D) (0.2 mg F/l). RESULTS: Children in the naturally fluoridated town showed slightly higher dmfs/dfs (SD) values for both 6-year olds [S: 9.1 (9.2), T: 7.2 (7.4), D: 7.1 (6.1)] and 9-year olds [S: 6.0 (6.2), T: 4.4 (4.2), D: 5.0 (4.7)], whereas the mean dmft/dft values as well as the numbers of caries-free children were comparable. A lower prevalence of dental restorations was reported for both Semnan and Dibaj compared with Teheran. A higher prevalence of fluorosis [Tooth Surface Index of Dental Fluorosis (TSIF) 3-7] was observed in the naturally fluoridated town compared with the low-fluoridated communities. CONCLUSIONS: The ingestion of naturally fluoridated water (1.3 mg F/l) seemed to have a negligible effect on caries prevalence, but resulted in higher prevalence of dental fluorosis. It is emphasized that the study population was not adjusted for socioeconomic status, availability of dental care nor for exposures to other sources of fluoride. Nevertheless, it can be concluded that caries prevalence in Iran is quite low compared with that in other countries in the Middle East and that the elevated fluoride levels in the drinking water in Semnan may contribute to the development of mild to severe fluorosis.  相似文献   
8.
Neurohormones like testosterone and estrogen have an important role in learning and memory. Many biological effects of androgens in the brain require the local conversion of these steroids to an estrogen. The current research has conducted to assess the effect of testosterone, estrogen and aromatase inhibitor (anastrozole) on spatial discrimination of rats, using Morris water maze and also the pathway of the effect of testosterone by using anastrozole. Adult male rats were bilaterally cannulated into CA1 region of hippocampus and divided into 15 groups. Different groups received DMSO 0.5 microl and DMSO 0.5 microl + DMSO 0.5 microl as control groups and different doses of testosterone enanthate (TE) (20, 40 and 80 microg/0.5 microl), estradiol valerat (EV) (1, 2.5, 5, 10, and 15 microg/0.5 microl), anastrozole (An) (0.25, 0.5, 1 microg/0.5 microl), TE 80 microg/0.5 microl + anastrozole 0.5 microg/0.5 microl and EV 15 microg/0.5 microl + anastrozole 0.5 microg/0.5 microl all days before training. TE and EV were injected 30-35 min before training and anastrozole was injected 25-30 min before training. Our results have shown both TE 80 microg/0.5 microl and EV 15 microg/0.5 microl groups increase in escape latency and traveled distance to find invisible platform. Also we have shown that anastrozole dose dependently decreases escape latency and traveled distance. We resulted that both TE and EN impaired acquisition of spatial learning and memory but anastrozole improved it. Anastrozole also could be buffered TE-induced impairment effect but not EV.  相似文献   
9.
Beta-Thalassemia (thal) is one of the most common genetic disorders in Iran and other countries. Getting information on the distribution of mutations in different ethnic groups of Iran is of fundamental importance for the purpose of health planning and prenatal diagnosis programs. One hundred and thirty chromosomes from 65 unrelated homozygous beta-thal patients were investigated for beta-globin gene mutations by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). The most common mutations of the Mediterranean region were examined in this study. Our results showed that the frameshift codons (FSC) 36/37 (-T) mutation, with a frequency of 33.8%, is the most common mutation in Lorestan Province. The other most frequent mutations were of the Mediterranean type and consisted of IVS-II-1 (G -->A), IVS-I-110 (G -->A), FSC 8/9 (+G) and IVS-I-5 (G -->C) with frequencies of 27.7, 11.5, 10.8 and 4.5%, respectively. The less frequent alleles, IVS-II-745 (C -->G), FSC 5 (-CT), IVS-I (25 bp deletion) and FSC 44 (-C) accounted for only 3.9% of the mutations. The unknown alleles comprised 7.7% of the mutations. These data showed that the spectrum of mutations found in Lorestan Province was different from those reported from other thalassemic regions of Iran and also of some neighboring countries.  相似文献   
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