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61.
Bassioni G Abdulla F Morsy Z El-Faramawy N 《Archives of environmental contamination and toxicology》2012,62(3):361-368
The distribution of natural nuclide gamma-ray activities and their respective annual effective dose rates, produced by potassium-40
(40K), uranium-238 (238U), thorium-232 (232Th), and radium-226 (226Ra), were determined for 14 oilfield scale samples from the Middle East. Accumulated radioactive materials concentrate in
tubing and surface equipment, and workers at equipment-cleaning facilities and naturally occurring radioactive materials (NORMs)
disposal facilities are the population most at risk for exposure to NORM radiation. Gamma-spectra analysis indicated that
photo-gamma lines represent the parents of 10 radioactive nuclides: 234Th, plutonium-239, actinium-228, 226Ra, lead-212 (212Pb), 214Pb, thallium-238 (208Tl), bismuth-212 (212Bi), 214Bi, and 40K. These nuclides represent the daughters of the natural radioactive series 238U and 232Th with 40K as well. The mean activity concentration of 238U, 232Th, and 40K were found to be 25.8 ± 11.6, 18.3 ± 8.1, and 4487.2 ± 2.5% Bq kg−1 (average values for 14 samples), respectively. The annual effective dose rates and the absorbed doses in air, both indoor
and outdoor, for the samples were obtained as well. The results can be used to assess the respective hazard on workers in
the field and represent a basis for revisiting current engineering practices. 相似文献
62.
Laura E. Thomas Joanna J. Hurley Angel Alonso Sanchez M. Rosario Aznárez Ann-Sofie Backman Jan Bjork Gabriel Capella Susan K. Clark Chrystelle Colas Evelien Dekker Sunil Dolwani Zeinab Ghorbanoghli Mark Gonn S. Gonzalez Romero Frederik J. Hes Hala Jundi Sarah Kelland Julian R. Sampson 《Gastroenterology》2021,160(3):952-954.e4
63.
Malak Mohammed Al-Hakeem Zeinab Abotalib Khalid Khalaf Alharbi Imran Ali Khan 《Clinical biochemistry》2014
Objectives
Gestational diabetes mellitus (GDM) is recognized as an imbalance between insulin resistance and insulin secretion, leading to maternal hyperglycemia. Previous studies in a Saudi population indicated a high frequency of Paraoxonase 1 glutamine 192 to arginine (PON1 Q192R) polymorphism, suggesting this polymorphism as an additional risk factor. The present study was designed to explore the possible association between the PON1 Q192R polymorphism and GDM in a Saudi population.Methods
This case–control study was carried out in 500 pregnant women, including 200 GDM cases and 300 non-GDM women. Genotyping for PON1 Q192R (rs662) variants was performed by polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP).Results
The results of the present study indicates that Q192R polymorphism was significantly associated with GDM in a Saudi population with the minor allele frequency (MAF) (p = 0.0007). Q192R genotypes and alleles showed a strong association with GDM (p = 0.009 and p = 0.0007, respectively).Conclusion
In conclusion, these findings suggest that the PON1 Q192R polymorphism has high MAF in GDM in the studied Saudi population. 相似文献64.
Hanan Abdel Haleem Naglaa Zayed Hanan Abdel Hafez Ahmed Fouad Maha Akl Mona Hassan Olfat Hammam Abdellah Morsy Azza Saleh Moataz Seyam Zeinab Zakaria Soher Zakaria 《Arab Journal Of Gastroenterology》2013,14(2):68-72
Background and study aimsHepatitis C virus (HCV) is considered the most common aetiology of chronic liver disease (CLD) in Egypt. The disease severity ranges from mild illness to cirrhosis and hepatocellular carcinoma. A role for apoptosis in liver damage caused by HCV chronic infection has been suggested. Cytokeratin 18 (CK-18) is the major intermediate filament protein in the liver and is a known caspase substrate in hepatocyte apoptosis. Therefore, we analysed the serum and tissue levels of CK-18 in patients with chronic HCV infection to evaluate its role in hepatocyte apoptosis. We also correlated CK-18 expression with the severity of hepatic pathology.Patients and methodsThis study examined 80 Egyptian patients with liver disease. There were 69 patients with chronic hepatitis C and 11 patients with hepatitis C-induced cirrhotic changes. Fifteen healthy controls were also included in the study. The levels of CK-18 fragment were quantified in paired serum and liver biopsy samples.ResultsThe serum and tissue CK-18 levels were reduced in chronic HCV patients compared to early cirrhosis patients. This result indicates that serum levels of CK-18 and the hepatic expression of CK-18 might play an important role in disease progression. The serum and tissue levels of CK-18 were significantly increased and directly correlated with inflammation severity, stage of fibrosis, and ALT levels in the chronic HCV group and the cirrhotic liver group. There was no significant difference in viral load between patient cohorts.ConclusionThe serum level and the hepatic expression of CK-18 are related to disease activity and are directly correlated with METAVIR scoring. This result suggests that serum CK-18 levels may be useful for monitoring disease activity in chronic HCV and liver cirrhosis patients. 相似文献
65.
66.
Akram Sadat Sadathosseini Reza Negarandeh Zeinab Movahedi 《Pain Management Nursing》2013,14(4):e196-e203
There are adverse physiologic effects of pain in neonates, and effective pain management must be an essential aspect of neonatal care. In this study we assessed the effect of a nonmaternal familiar scent on the neonatal pain responses. This study included 135 neonates randomly assigned to one of three groups. During arterial puncture, one group was exposed to a vanillin scent on a gauze pad held next to their nose. They were familiarized with it the night before blood sampling by a scented gauze pad placed in the incubator next to their head for an average duration of 8.65 hours. The second group was not familiarized with the scent but was exposed to it during the procedure. The third group was neither familiarized nor exposed to the scent. The duration of crying in the familiar scent group was significantly lower than in the two other groups. Comparison of the physiologic parameters showed less variation in oxygen saturation level during arterial puncture in the familiar scent group. In this study, a familiar scent could reduce crying and oxygen consumption during arterial puncture. 相似文献
67.
Mohammed M. Dar AB Zeinab Abdel-Wahab PhD Carol E. Vervaert MT Tim Darrow PhD Jack Barber PhD Dr. H. F. Seigler MD 《Annals of surgical oncology》1996,3(3):247-254
Background: Recent studies have demonstrated the usefulness of gene-modified tumor cells for immunotherapy. Using the tumorigenic murine
fibrosarcoma, MCA 106, we investigated the effects of localized interferon-γ (IFNg) secretion on tumorigenicity and on long-term memory.
Methods: The murine IFNg (MuIFNg) gene was introduced into tumor cells. High and low IFNg-secreting clones were isolated. C57BL/6
mice were injected subcutaneously (s.c.) with either parental (P), high or low IFNg-secreting (H- or L-IFNg) cells, and tumor
growth was assessed weekly. Spleens were harvested on different days postinjection (p.i.) to assess in vitro cytolytic activity.
In parallel, tissues from injection sites were stained with macrophage-, CD4-, and CD8-detecting antibodies. Mice were injected
s.c. with H-IFNg MCA106 tumor. After 150 days the animals were rechallenged s.c. with MCA106P in one leg and with irrelevant
syngeneic tumor in the other.
Results: Both P- and L-IFNg cells had similar growth, whereas the H-IFNg cells never grew. Only splenocytes from the H-IFNg animals
showed in vitro CTL activity persisting until day 30 p.i. Histological data revealed a macrophage and CD4+ infiltrate much earlier in the H-IFNg group compared with the P group. Only the irrelevant, syngeneic tumor grew in animals
previously injected with H-IFNg cells, whereas both P and irrelevant syngeneic tumors grew in controls.
Conclusions: Transduction of MCA106 cells with the MuIFNg gene diminished in vivo tumorigenicity in proportion to the amount of IFNg secreted.
Immunization with H-IFNg cells elicited a host response characterized by macrophages and CD4+ cells. Long-term tumor-specific memory was seen after immunization with H-IFNg cells. 相似文献
68.
69.
70.
Protective effects of L-arginine against cisplatin-induced renal oxidative stress and toxicity: role of nitric oxide 总被引:2,自引:0,他引:2
Nephrotoxicity is a dose-limiting factor in clinical use of cisplatin. The changes in renal haemodynamics were suggested to play a role in cisplatin-induced nephrotoxicity. The aim of the present study was to investigate the effect of modulation of nitric oxide on the severity of cisplatin-induced nephrotoxicity using an experimental rat model. A nitric oxide precursor, L-arginine and an inhibitor of nitric oxide synthase, L-NAME were used. After six days of cisplatin injection, acute nephrotoxicity was demonstrated by a marked increase in serum creatinine and blood urea nitrogen. Histological examination of the kidneys confirmed the occurrence of renal damage. Moreover, cisplatin induced an increase in the level of lipid peroxides and oxidized glutathione and a depletion of reduced glutathione. The activities of the antioxidant enzymes glutathione peroxidase and superoxide dismutase were also lowered. Besides, there was a reduction in the kidney total nitrate/nitrite levels. L-arginine significantly attenuated the oxidative stress and nephrotoxic effect of cisplatin. On the other hand, L-NAME was found to aggravate cisplatin nephrotoxicity. In conclusion, the decrease in the kidney nitric oxide level contributes, at least in part, in the mechanism underlying the nephrotoxicity of cisplatin. Furthermore, L-arginine shows nephroprotective effects and might be useful in improving the therapeutic index of cisplatin. 相似文献