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71.
A heavy metal is any relatively dense metal that may be potentially toxic in a variety of foods. Heavy metals pollute and contaminate foods. These metals are usually toxic to human body. Heavy metals are the most important toxic metals which may cause health risks following the consumption of contaminated foods. The edible salt (NaCl) is a substance that has been used as a food additive since ancient times. Twenty samples of refined and unrefined edible salts produced in Iran were analyzed using flame atomic absorption spectrometry (FAAS) method for the presence of toxic heavy metals. The precision of the analysis was assured through the repeated analysis of the samples. The mean (±standard deviation) concentrations of toxic metals in dried samples of rock salt were as follows: Ni (1.870?±?0.850), Cd (0.328?±?0.143), Mn (0.184?±?0.230) and Co (3.124?±?0.880) mg/kg and in dry weights of samples obtained from Urmia market: Ni (1.982?±?0.021), Cd (2.461?±?0.036), Mn (0.192?±?0.028) and Co (8.450?±?0.025) mg/kg. There was a significant difference between the toxic metal concentrations and their guideline values. Therefore, it was important to assess the public health risks posed by the presence of toxic contaminants. 相似文献
72.
妊娠期贫血原因分析及贫血时对母婴的影响 总被引:11,自引:0,他引:11
本文测定227例正常初产妇,于不同孕期取静脉血,测定血清铁蛋白(SF)等6项指标进行追踪观察。结果:孕妇妊娠期铁贮备、血清叶酸(FA)、维生素(VB12),随孕龄增加呈显著性降低;而缺铁性贫血(IDA)、巨幼红细胞盆血(MA)和混合性盆血发生率呈逐渐增高趋势。贫血发生率30.4%,贫血合并妊高征发生率27.54%。作者认为妊娠中、后期补充铁剂、FA和VB12是防治贫血的重要措施。 相似文献
73.
74.
Mozaffari F Hansson L Kiaii S Ju X Rossmann ED Rabbani H Mellstedt H Osterborg A 《British journal of haematology》2004,124(3):315-324
T-cell immune dysfunction in patients with malignant tumours has been attributed to the altered expression of components of the T-cell receptor (TCR)/CD3 complex and their associated intracellular protein tyrosine kinases. In this study, four-colour flow cytometry was applied to study the surface bound molecules TCRalphabeta, CD28, CD152 and CD154 involved in T-cell signalling and the signal transduction molecules CD3zeta, p56lck, p59fyn, ZAP-70 and phosphatidyl-inositol-3 kinase (PI3-k) as well as the intracellular cytokines interferon-gamma (IFN-gamma), interleukin (IL)-4 and IL-2 as a functional read-out of non-stimulated and superantigen (staphylococcus enterotoxin B)-stimulated blood T cells of multiple myeloma (MM) patients at different stages of the disease. Multiple abnormalities were demonstrated in the CD4 and CD8 populations, both under non-stimulated and superantigen-stimulated conditions. There was a marked reduction, particular in advanced stage MM, in the proportion of CD4 and CD8 cells expressing CD28, CD152, CD3zeta, p56lck, ZAP-70 and PI3-k. The level of intracellular T-cell cytokines (IFN-gamma, IL-2 and IL-4) was normal or increased in non-stimulated cells but activation-induced cytokine production was impaired. These results illustrated profound and multiple T-cell signalling defects, from the surface and down-stream, consistent with involvement of a master T-cell function, especially in advanced stage MM. These data should be taken into consideration when developing immune-based therapeutic approaches and when applying new emerging technologies that aim to restore T-cell functions. 相似文献
75.
The vascular effects of glucose-intolerance were investigated using the neonatal streptozotocin-treated (nSTZ) rat model. Glucose-intolerance was initiated by administration of STZ (90 mg/kg, IP) into 2-day-old male rats. Aortic reactivity was assessed in vitro at 3 and 6 months of age. Both the 3- and 6-month-old nSTZ rats displayed higher blood glucose levels in response to a glucose challenge. At 3 months of age, aortic responsiveness to both norepinephrine and acetylcholine was not altered. However, at 6 months of age, the responses of endothelium-denuded aortas from nSTZ rats to norepinephrine and serotonin were enhanced compared to controls. Endothelium-mediated relaxation of aortas from these animals to acetylcholine was also augmented, and this effect was linked to NO release. Although norepinephrine did not elicit enhancement of aortic contraction in calcium-free medium in 6-month-old nSTZ rats, the responses to both maximum and submaximum concentrations of the agonist after readdition of calcium were greater in these tissues than in control preparations. Pretreatment of aortas with calphostin C eliminated the difference in NE-induced contraction between the control and experimental groups. Although the concentration-response curves for phorbol 12,13-dibutyrate were not different between the 2 groups, the responses of the aortas from 6-month-old nSTZ rats to a submaximum concentration of the phorbol ester were enhanced relative to controls, and this enhancement was normalized with calphostin C. Overall, the data suggest that glucose-intolerance of sufficient duration causes increases in vascular reactivity to agonists. While these findings warrant further investigations, such vascular alterations during the prediabetes stage of glucose intolerance can be a predisposing factor for the eventual development of cardiovascular complications. 相似文献
76.
Irritable bowel syndrome (IBS) is a highly prevalent chronic functional gastrointestinal (GI) disorder associated with abdominal pain and change in bowel habits that its etiology is not known yet. In the recent years, melatonin has been proposed as a possible candidate. In the present work, all clinical or non-clinical data about effects of melatonin in GI tract and IBS obtained from literature without time limit up to August 2010 have been studied and reviewed. Eight clinical trials were reviewed for efficacy and disturbance of melatonin in IBS and other GI disorders. The results showed disturbances in endogenous melatonin concentration in IBS patients and significant benefits of exogenous melatonin in these patients by decreasing abdominal pain and improvement of overall IBS symptom scores. The results of seventeen non-clinical studies showed anxiolytic, anti-inflammatory, anti oxidative and motility regulatory effects of melatonin on GI tract. In conclusion melatonin can be a target of interest in IBS because of its potentials to regulate GI motility. 相似文献
77.
Fazlollahi MR Aghamohammadi A Hosseini RF Lotfi AS Khoshdel A Farhoudi A Movahedi M Gharagozlou M Mozaffari H Zandieh F Mansouri M Ghaffari J Rezaei N 《Iranian journal of allergy, asthma, and immunology》2006,5(2):69-74
Primary antibody deficiencies are the most frequent primary immunodeficiency disorders. Bronchiectasis as a feature of these disorders may be developed due to some factors such alpha-1- antitrypsin deficiency. In order to determine the prevalence of two common alpha-1-antitrypsin deficiency alleles (PI*Z and PI*S) in Iranian patients with antibody deficiency, this study was performed. The prevalence of PI*M, PI*S, and PI*Z allele combinations was determined in 40 patients with primary antibody deficiency (with and without bronchiectasis) and compared with 60 healthy control subjects. Phenotyping was performed by isoelectric focusing. The phenotype frequencies among patients were as follow: M in 92.5%, S in 2.5% and Z in 5%. There was not any significant difference in distribution of alleles or phenotypes between patients and control subjects. Moreover, no significant difference was found between patients with and without bronchiectasis. We did not find evidence to support an association between alpha-1-antitrypsin phenotypes and primary antibody deficiencies in a small, controlled study. Larger studies will be required to clarify the relationship between alpha-1-antitrypsin genotype and susceptibility to bronchiectasis in patients with antibody deficiency. 相似文献
78.
Mohammadianpanah M Ahmadloo N Mozaffari MA Mosleh-Shirazi MA Omidvari S Mosalaei A 《Annals of hematology》2009,88(5):441-447
The aim of this retrospective study was to define the natural history, clinicopathological findings, prognostic factors, and
treatment outcome of 43 patients with localized stages I and II primary non-Hodgkin’s lymphoma (NHL) of the nasopharynx, followed
up in a single institution over a 17-year period. Forty-three (13 women and 30 men) consecutive patients with localized stages
I (N = 12) and II (N = 31) primary nasopharyngeal NHL were treated in our institution between 1990 and 2007. The pathologic reports were classified
according to the International Working Formulation (N = 22) or Revised European-American Lymphoma classification (N = 21). The vast majority of patients (88%) were managed with a sequential combination of chemotherapy and radiation therapy.
Chemotherapy mainly consisted of 4–8 (median 6) cycles of CHOP regimen (cyclophosphamide, doxorubicin, vincristine and prednisolone).
Involved-field radiation therapy with a median dose of 44 Gy was delivered to the primary site and entire cervical lymph nodes.
The median age of the patients was 53 years (range, 6 to 86 years). The majority of the patients (70%) had high-grade histology.
B-cell types represented 67% of the cases, among which diffuse large B cell was the most common histological subtype. After
a median follow-up of 70 months, the 5-year disease-free survival and overall survival were 58.8% and 70.6%, respectively.
In multivariate analysis, age less than or equal to 30 years (hazard ratio (HR) = 5.32, 95% confidence interval (CI) = 1.69–16.76),
elevated serum lactate dehydrogenase level (HR = 3.69, 95% CI = 1.43–9.51), and modified International Prognostic Index with
more than or equal to two risk factors (HR = 17.99, 95% CI = 2.32–139.30) retained statistical significance. Our limited data
suggest that primary nasopharyngeal NHL tends to have aggressive histology and unfavorable clinical course with poor outcome,
despite a considerably localized disease at the time of presentation and high frequency of complete initial response rates.
Combined modality therapy should be considered for the majority of patients with primary localized nasopharyngeal NHL. 相似文献
79.
孙世澜 《内科急危重症杂志》2009,15(6):288-289
所谓特发性急性间质性肾炎(idiopathic acute interstitial nephritis),系指临床上无明确病因可循的一类急性间质性。肾炎,疾病的前驱期亦缺乏特异性,在前驱症状出现不久出现少尿性急性肾衰竭。临床上分为:①急性间质性肾炎-眼葡萄膜炎(tubulointerstitial nephritis—uveitis,TINU)综合征; 相似文献
80.