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排序方式: 共有2950条查询结果,搜索用时 31 毫秒
991.
Salma Samir Omar Wally Mahfouz Waleed Dawood Reham Abdel Haleem Abo El-Wafa Rasha Abdelmawla Ghazala Abdel-Rahman Mahmoud Zahran 《Andrologia》2020,52(3):e13525
The pathophysiology of varicocele remains to be unknown. Several genetic factors have been implicated in varicocele etiopathogenesis. We studied the relationship between NOS3 c.894G>T, c.786T>C and 4b/a polymorphisms to varicocele risk and their prognostic value as regards improvement of the post-operative seminal parameters &/or seminal malonaldehyde levels. The three NOS3 polymorphisms were evaluated in 100 patients with varicocele and 100 healthy subjects by RT-PCR. Seminal plasma MDA level was measured pre-operatively and 3 months after varicocelectomy by the thiobarbituric acid method. The GT, TT, TC and bb genotypes of NOS3 polymorphism were more commonly observed in varicocele patients (30%, 9%, 28% and 70% respectively) compared to normal controls (12%, 0%, 10% and 50% respectively). The mean percentage of post-varicocelectomy seminal MDA reduction was highest with the GT genotype (p < .001). Genotypes GT+TT, TC and bb were associated with varicocele occurrence in our patients. The T (c.894G>T), C (c.786T>C) and b (NOS3 intron 4 VNTR) alleles were significantly associated with varicocele occurrence in our cohort of patients. We also report a better response regarding the reduction of seminal MDA after varicocelectomy with the GT and ba genotypes. 相似文献
992.
Gamal Allam Amre Nasr Iman M. Talaat Abdelaziz S. A. Abuelsaad Ali M. Bakheit Dalal Nemenqani 《Immunological investigations》2018,47(3):229-240
Background: Association studies of genes encoding cytokines that play an important role in inflammatory response represent one approach to finding type 1 diabetes (T1D) disease genes. The aim of this study was to investigate the association of single nucleotide polymorphisms (SNPs) within cytokine genes with T1D in a cohort of Saudi subjects. Methods: A total of 300 well-characterized type 1 diabetic patients and 300 T1D-free control subjects were enrolled in this investigation. Cytokine SNPs were genotyped by using Polymerase chain reaction (PCR) with sequence-specific primers. Results: Our data revealed that IFN-γ +874T allele carriers [odds ratio (OR) = 1.87, p < 0.001] and TT homozygotes (OR = 1.28, p < 0.001) were significantly more susceptible to developing T1D than the A allele carriers. In addition, TNF-α ?308A allele carriers (OR = 1.73, p < 0.001) and AA homozygotes (OR = 1.74, p < 0.001) were also overrepresented among the diabetics than G allele carriers. IL-4 ?590C/T TT homozygotes (OR = 2.23, p < 0.001) were significantly more susceptible to develop T1D than CC genotypes, whereas CT heterozygotes were not significantly associated (OR = 1.43, p = 0.78) with T1D. Furthermore, IL-4 T allele was statistically associated with T1D patients compared to control group (OR = 2.24, p < 0.001). Similarly, IL-1β ?511C/T TT homozygotes (OR = 1.85, p = 0.012) and the T allele (OR = 1.85, p < 0.001) were significantly more susceptible to T1D than CC genotypes, whereas TC heterozygotes (OR = 1.04, p = 0.86) were not significantly associated with T1D. Conclusion: Our data concluded that IFN-γ +874T allele, TNF-α ?308A allele, IL-1β ?511T allele, and IL-4 ?590T allele could be considered risk factors for T1D development in Saudi subjects. 相似文献
993.
Anti‐Müllerian hormone levels in patients with turner syndrome: Relation to karyotype,spontaneous puberty,and replacement therapy 下载免费PDF全文
Rasha T. Hamza Marwa F. Mira Amira I. Hamed Treiz Ezzat Mahmoud T. Sallam 《American journal of medical genetics. Part A》2018,176(9):1929-1934
Most girls with Turner syndrome (TS) suffer from incomplete sexual development, premature ovarian failure, and infertility due to abnormal ovarian folliculogenesis. Serum anti‐Müllerian hormone (AMH) levels reflect the ovarian reserve in females, even in childhood. Thus, we aimed to assess serum AMH levels in girls with TS and its relation to karyotype, spontaneous puberty, and growth hormone (GH) therapy. Fifty TS were compared to 50 age‐ and sex‐matched controls. All subjects were subjected to history, anthropometric assessment, Tanner pubertal staging and measurement of serum follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), and AMH. Karyotype results were obtained from patients’ records. Serum AMH was measurable in 12 TS patients (24%). The lowest frequency of measurable AMH was in patients with a karyotype of 45,X. The measurable AMH was associated with spontaneous breast development (p = .003) and spontaneous menarche (p = .001). AMH correlated negatively with FSH (r = ?.846, p = .000) and LH (r = ?.83, p = .034). GH therapy increased the odds of having measurable AMH in TS girls (p = .002). In conclusion, AMH was associated with karyotype, spontaneous pubertal development, LH, and FSH in TS girls and may serve as a useful marker of ovarian function and ongoing follicular development in prepuberty. 相似文献
994.
Chlorine dioxide metabolism in rat 总被引:1,自引:0,他引:1
M S Abdel-Rahman D Couri J D Jones 《Journal of environmental pathology and toxicology》1979,3(1-2):421-430
Chlorine dioxide (ClO2) is under consideration as an alternative to chlorination as a disinfectant for public water supplies. A new assay was developed to qualitatively and quantitatively measure the metabolites of 36ClO2 in water and biological fluids. Studies in the rat indicated that the metabolites of ClO2 were Cl-, ClO-2, and ClO-b. At maximum absorption the percentage of ClO; formed in plasma from an initial oral dose of 10 mg/l 36ClO, was higher than from a 100 mg/l dose. The 36Cl concentration in washed packed cells indicated that 36Cl readily exchanges with chloride of saline. 相似文献
995.
996.
Correlation between RUST assessments of fracture healing to structural and biomechanical properties 下载免费PDF全文
Margaret E. Cooke Amira I. Hussein Kyle E. Lybrand Alexander Wulff Erin Simmons Jeffrey H. Choi Jody Litrenta William M. Ricci Jason W. Nascone Robert V. O'Toole Elise F. Morgan Louis C. Gerstenfeld Paul Tornetta III 《Journal of orthopaedic research》2018,36(3):945-953
997.
A R Abdel-Rahman M S Dar W R Wooles 《The Journal of pharmacology and experimental therapeutics》1985,232(1):194-201
The effect of chronic ethanol administration on arterial baroreflexes was investigated in rats. Comparison of the results with those obtained from rats kept on an isocaloric control diet revealed that chronic ethanol had a differential action on baroreflex sensitivity (BS). The BS after evoked graded rises in arterial pressure was inhibited significantly whereas that tested after an evoked fall in arterial pressure was augmented significantly in chronic ethanol rats. These changes in BS were not secondary to changes in blood pressure as resting arterial pressure was similar in both groups. However, the heart rate was slightly, but significantly lower in the ethanol group. Challenging isocaloric control and chronic ethanol rats with an acute dose of 0.5 g/kg of ethanol produced nonsignificant changes in BS when evoked changes in blood pressure were both pressor and depressor. A dose of 3 g/kg of ethanol decreased the BS tested after phenylephrine-evoked rises in pressure in both groups; however, the percentage of inhibition of BS was greater in the isocaloric control group. The pressor responsiveness to phenylephrine was reduced slightly in chronic ethanol-treated rats, in contrast to that evoked by angiotensin II which was augmented slightly as compared to the control group. There was no significant difference in the depressor responsiveness to nitroprusside. After injection of acute doses of 0.5 and 3 g/kg of ethanol, the dose-response curves to phenylephrine were shifted to the right in a dose-related fashion in both groups, whereas the angiotensin II and nitroprusside dose-response curve remained unchanged after 0.5 g/kg of ethanol in both groups.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
998.
999.
Moustafa M. A. Mossalem H. S. Sarhan R. M. Abdel-Rahman A. A. Hassan E. M. 《Parasitology research》2018,117(12):3867-3880
Parasitology Research - Schistosomiasis seriously affects human health in tropical regions. Its prevention is more important than treatment, raising the need for effective control methods.... 相似文献
1000.
Gad GF El-Domany RA Zaki S Ashour HM 《The Journal of antimicrobial chemotherapy》2007,60(5):1010-1017
OBJECTIVES: To assess the prevalence, levels of antimicrobial susceptibility and resistance mechanisms of Pseudomonas. METHODS: A total of 445 clinical isolates and 200 environmental isolates were collected from three hospitals in Minia, Egypt. The MICs of different antibiotics were determined using the agar dilution method. The isolates were tested for beta-lactamase production and for the presence of efflux pumps. RESULTS: Out of the 445 clinical specimens, 107 Pseudomonas strains (24%) and 81 Pseudomonas aeruginosa strains were isolated (18.2%). Out of the 200 environmental specimens, 57 Pseudomonas strains (28.5%) and 39 P. aeruginosa strains were isolated (19.5%). Amikacin was the most active drug against P. aeruginosa followed by meropenem, cefepime and fluoroquinolones. P. aeruginosa was highly resistant to all other antibiotics tested. The environmental isolates of P. aeruginosa exhibited higher antibiotic resistance than clinical isolates. Mechanisms of resistance used by P. aeruginosa included beta-lactamase production and multiple drug resistance efflux pumps. Our results showed that 29 (36%) of the clinical P. aeruginosa isolates and 37 (95%) of the environmental P. aeruginosa isolates were beta-lactamase producers. In addition, P. aeruginosa isolates effectively used an efflux-mediated mechanism of resistance against ciprofloxacin and meropenem, but not gentamicin or cefotaxime. CONCLUSIONS: This study examined the prevalence of P. aeruginosa, and its susceptibility patterns to different antibiotics. The presence of antibiotic-resistant P. aeruginosa isolates could be attributed to beta-lactamase production and the use of multiple drug resistance efflux pumps. 相似文献