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排序方式: 共有994条查询结果,搜索用时 15 毫秒
101.
Evaluation of renal glomerular and tubular functional and structural integrity in neonates 总被引:5,自引:0,他引:5
Awad H el-Safty I el-Barbary M Imam S 《The American journal of the medical sciences》2002,324(5):261-266
BACKGROUND: Renal cells are not fully differentiated at birth, representing a major risk in preterm infants. We evaluated glomerular and tubular functional integrity as well as structural integrity of renal tubules among healthy full-term and preterm infants as well as diseased preterm infants. METHODS: A total of 50 newborns (10 healthy full-term, 10 healthy preterm, and 30 diseased preterm, at 38.9 +/- 1.10, 34.2 +/- 0.92, and 32 +/- 2.47 weeks gestational age, respectively) were included in the present study. Glomerular function was assessed by measuring urinary levels of both microalbumin and immunoglobulin G as well as serum creatinine levels, whereas the proximal tubular function was investigated by measuring the urinary levels of both alpha1-microglobulin and beta2-microglobulin as well as retinol-binding protein. Also, distal tubular reabsorption capacity was investigated by assessing fractional excretion of sodium. Moreover, the structural integrity of renal proximal tubules was studied by measuring the urinary activities of both the brush-border membrane enzyme leucine-aminopeptidase (LAP) and the lysosomal enzyme N-acetyl-beta-D-glucosaminidase. The preceding investigations were done on both the first and third days of life of all 50 newborns. RESULTS: Glomerular and tubular function and structure was relatively impaired at birth among both healthy and diseased preterm as well as healthy full-term neonates and improved rapidly thereafter. The diseased preterm neonates showed worse renal function and structure with minimal improvement regardless of the underlying sickness. CONCLUSION: Renal insufficiency and renal immaturity could be evaluated using enzymuria and low- and high-molecular-weight proteinuria as noninvasive methods. 相似文献
102.
Sarah Alsubhi Amal Alhashem Eissa Faqeih Majid Alfadhel Abdullah Alfaifi Waleed Altuwaijri Saud Alsahli Hesham Aldhalaan Fowzan S. Alkuraya Khalid Hundallah Adel Mahmoud Ali Alasmari Fuad Al Mutairi Hanem Abduraouf Layan AlRasheed Saad Alshahwan Brahim Tabarki 《American journal of medical genetics. Part A》2017,173(10):2614-2621
103.
A. I. Abd-Elhamid A. A. Nayl Ahmed A. El. Shanshory Hesham M. A. Soliman H. F. Aly 《RSC advances》2019,9(10):5770
Cotton fiber–graphene oxide (C–GO) composite with high adsorptive properties towards the cationic dye, crystal violet (CV), was successfully fabricated by simple mixing of cotton fiber and GO in aqueous solution using a homogenizer. The as-prepared composite was characterized using TEM, SEM, LOM, XRD, FTIR, Raman and TGA. The characterization indicated that the formation of a homogeneous composite occurred via adequate mixing of the cotton fiber and GO. The fine structure of the obtained composite was successfully used in two adsorption techniques, namely batch adsorption and filter adsorption. Various parameters affecting batch adsorption, such as contact time, dye concentration, composite dose, NaCl dose, temperature and pH were investigated. In the filter adsorption mode, dye concentration, composite dose, NaCl dose, temperature, flow rate and pH were studied. A comparison study between the two techniques, i.e., batch adsorption and filter adsorption, are reported. The filter adsorption technique shows higher adsorption efficiency than the batch one, which was evident from the maximum adsorption capacity (Q°) values, obtained from the Langmuir isotherm. Further, the filter technique was developed and evaluated. This was achieved by regeneration, scaling-up and, finally, using another model of cationic dye (methylene blue).Cotton fiber–graphene oxide (C–GO) composite with high adsorptive properties towards the cationic dye, crystal violet (CV), was successfully fabricated by simple mixing of cotton fiber and GO in aqueous solution using a homogenizer. 相似文献
104.
El-Awady MK Mostafa L Tabll AA Abdelhafez TH Bader El Din NG Zayed N Shenawy RE El Abd Y Hasan RM Zaghlol H El Khayat H Abdel Aziz AO 《Hepatitis monthly》2012,12(4):271-277
Background
IL28B single nucleotide polymorphisms (SNPs) play important roles in the management of hepatitis C virus (HCV) infections and are strongly associated with spontaneous and treatment-induced HCV clearance.Objectives
In the present study, the association between IL28B variants and the progression of HCV infection in Egyptian patients infected with type 4a virus will be examined.Patients and Methods
Frequencies of the protective genotype C/C of SNP, rs12979860 were determined in healthy subjects, spontaneous resolvers, and chronic HCV type 4 patients with low F scores and in patients with end stage liver disease (ESLD). This study included a total of 404 subjects. Patients infected with HCV type 4a (n = 304) were divided into; chronic hepatitis C (CHC) with low F scores (CHC, n = 110), end stage liver disease (n = 110), liver cirrhosis (LC) (n = 35) and hepatocellular carcinoma (HCC) patients (n = 75), spontaneous resolvers of HCV infection (n = 84) were also included. A healthy group representing the Egyptian population (n = 100) was also included in the genotyping of IL28B. The later was typed via a polymerase chain reaction based restriction fragment length polymorphism (PCR-RFLP) assay analysis on purified genomic DNA extracted from all individuals.Results
A significant increase (P < 0.0005) was observed in frequencies of IL-28B rs12979860 C/C genotypes in the healthy population, than in the CHC, LC and HCC groups (C/C = 48%, 13%, 0%.and 0% respectively). On the other hand the C/C genotype was significantly higher (P < 0.0005) in spontaneous resolvers than in healthy subjects. A comparable significant increase in the frequency of C/T allele accompanied by mild elevation of T/T allele frequency, were detected along the progression towards ESLD.Conclusions
Genotype C/C is associated with viral clearance during acute infection. The sharp decline in the C/C genotype from healthy to CHC subjects and the total absence of the C/C genotype in ESLD suggests a central role of this genotype against HCV disease progression. 相似文献105.
Ahmed H. Abou-Issa Wael Abdulghaffar Fady Elganayni Mohammad Bafaraj Hesham Fathy Soliman 《The Egyptian Journal of Radiology and Nuclear Medicine》2012
Blunt thoracic aortic injury is associated with a high mortality rate. It is the second leading cause of death after head injury from vehicle accidents. Surgical repair with graft interposition was the traditional treatment of blunt aortic injury however; the introduction of endovascular stent graft has revolutionized the definitive treatment of these injuries. 相似文献
106.
This study aimed to determine the mycological profile of the retail date fruits distributed in different markets at Taif, Saudi Arabia. The presence of aflatoxins and ochratoxin A was also measured. Twenty-two fungal species belonging to 12 genera were isolated from 50 different date samples. Aspergillus flavus, A. niger, Penicillium chrysogenum, and Rhizopus stolonifer were the most prevalent species among isolated fungi. Eighty isolates of A. flavus and 36 of A. niger were detected for their aflatoxins and ochratoxin production potentials using thin layer chromatography. Toxicity test using Artimia larvae indicated that seven out of 18 A. flavus isolates had aflatoxins potentials, while nine out of 36 isolates of A. niger were ochratoxigenic. The quadruplex polymerase chain reaction using specific primers demonstrated the presence of four genes: nor A, ver 1, omt A, and avf A in seven A. flavus toxigenic isolates. Nine A. niger toxigenic isolates showed positive results for the presence of the PKS gene. In conclusion, the present study highlighted the potential hazards of mycotoxins on human health from consuming raw dates. Rapid molecular detection methods described here might help the food authorities to assure the safety of raw dates distributed in local markets. 相似文献
107.
PTH binding to the PTH/PTHrP receptor activates adenylate cyclase/protein kinase A (PKA) and phospholipase C (PLC) pathways and increases receptor phosphorylation. The mechanisms regulating PTH activation of PLC signaling are poorly understood. In the current study, we explored the role of PTH/PTHrP receptor phosphorylation and PKA in PTH activation of PLC. When treated with PTH, LLCPK-1 cells stably expressing a green fluorescent protein (GFP)-tagged wild-type (WT) PTH/PTHrP receptor show a small dose-dependent increase in PLC signaling as measured by inositol trisphosphate accumulation assay. In contrast, PTH treatment of LLCPK-1 cells stably expressing a GFP-tagged receptor mutated in its carboxyl-terminal tail so that it cannot be phosphorylated (PD-GFP) results in significantly higher PLC activation (P<0.001). The effects of PTH on PLC activation are dose dependent and reach maximum at the 100 nm PTH dose. When WT receptor-expressing cells are pretreated with H89, a specific inhibitor of PKA, PTH activation of PLC signaling is enhanced in a dose-dependent manner. H89 pretreatment in PD-GFP cells causes a further increase in PLC activation in response to PTH treatment. Interestingly, PTH and forskolin (adenylate cyclase/PKA pathway activator) treatment causes an increase in PLCbeta3 phosphorylation at the Ser1105 inhibitory site and that increase is blocked by the PKA inhibitor, H89. Expression of a mutant PLCbeta3 in which Ser1105 was mutated to alanine (PLCbeta3-SA), in WT or PD cells increases PTH stimulation of inositol 1,4,5-trisphosphate formation. Altogether, these data suggest that PTH signaling to PLC is negatively regulated by PTH/PTHrP receptor phosphorylation and PKA. Furthermore, phosphorylation at Ser1105 is demonstrated as a regulatory mechanism of PLCbeta3 by PKA. 相似文献
108.
Mahmoud Alhosiny Fayed Hesham El-Sayed Abdel-Hady Mona Mohammed Hafez Osama Saad Salama Youssef Abdelhalim Al-Tonbary 《Hematology/oncology and stem cell therapy》2018,11(2):65-74
Background
The increased survival rate of thalassemic patients has led to unmasking of management related complications which were infrequently encountered.Objective
Study the increased coagulation and platelet activation in children with β-thalassemia, to analyze the factors that lead to such hypercoagulable state and to study pulmonary hypertension (PH) in conjunction with platelet activation and hypercoagulable state in children with β-thalassemia.Methods
36 Egyptian children with β-thalassemia with a mean age of 9.9 years (±4.7 SD). In addition, 20 healthy Egyptian children matched for age and sex were enrolled as a control group. Both were subjected to clinical and laboratory assessments. Echocardiography was done to the patient group and PH was diagnosed based on calculated mean pulmonary artery pressure [MPAP] >25 mmHg.Results
We found that, mean ± SD serum P-selectin level (platelet activator marker) was significantly higher in thalassemic patients (2337 ± 566 pg/ml) in comparison to controls (1467 ± 247 pg/ml) (P < 0.001). Mean serum protein-C and antithrombin-III levels were significantly lower in thalassemic patients (1.2 ± 1.3 µg/ml, 27.3 ± 7.5 mg/dl) in comparison to controls (2.3 ± 1.3 µg/ml, 35.1 ± 4.1 mg/dl) (P = 0.003 and <0.001) respectively. PH was detected in 17 (47.2%) patients and it was significantly associated with splenectomy (P = 0.01) and non-transfusion dependent thalassemia (NTDT) (P = 0.04). PH was positively correlated with serum levels of P-selectin (r = 0.38, P = 0.02), fibrinogen (r = 0.41, P = 0.01) and negatively correlated with serum protein-C level (r = ?0.48, P = 0.003).Conclusion
A chronic hypercoagulable state and platelet activation is present in children with β-thalassemia. Splenectomy and transfusion infrequency are the main risk factors noted to be associated with such hypercoagulable state and platelet activation and consequently the PH among our thalassemic patients. 相似文献109.
Silvana C. Faria Janio Szklaruk Ahmed O. Kaseb Hesham M. Hassabo Khaled M. Elsayes 《Abdominal imaging》2014,39(5):1070-1087
Hepatocellular carcinoma (HCC) is a major health problem worldwide. Moreover, the liver cancer field is evolving rapidly, with early diagnosis, new therapies, and a better understanding of HCC’s biology and development. Accurate staging is important for determining prognosis and selecting the most appropriate treatment for each patient. Surgical intervention remains the most effective treatment for HCC and is the only potentially curative modality. However, in HCC patients, overall survival is also independently affected by underlying liver disease and cirrhosis, which in turn affect the applicability and efficacy of treatment. Although several staging classification and prognostic scoring systems have been proposed for determining the stage and prognosis of HCC, no consensus exists on the best classification method. The most common staging classification systems include tumor-node-metastasis stage, Okuda staging, Cancer of the Liver Italian Program score, Barcelona Clinic Liver Cancer staging classification, the French, the Chinese University Prognostic Index, Japanese Integrated Scoring, and the Tokyo score. Radiologists should be aware of the different staging classification systems for HCC and familiar with the system relevant to their respective referring clinicians, as it will provide pertinent radiological evaluation for multidisciplinary management. 相似文献
110.
Ragaa H M Salama Ahmed Y A Nassar Allam A M Nafady Hesham H T Mohamed 《Liver international》2007,27(4):454-464
BACKGROUND: Fatty liver is the accumulation of fat in liver cells, which leads to disruption of the normal liver structure and function. METHODS: A non-alcoholic fatty liver rat model received copper (Cu) (I)-nicotinate complex [CuCl(HNA)2] for 4 weeks. RESULTS: Clinical signs and histopathological examinations showed obvious improvements in rats that received Cu complex who were continuously on an (HCFF) diet than those returned to standard diet with Cu complex. The improvement was matched in total lipids in sera and hepatic tissue, with disappearance of fat droplets from liver sections. Furthermore, the gain in body weight and the corresponding decrease in liver weight, decreased liver transaminases and alkaline phosphatase were prominent. The oxidative stress markers such as nitric oxide, lipid peroxides, glutathione and superoxide dismutase were obviously changed to healthy normal levels. CONCLUSION: The Cu complex may serve as a novel chemical restoring agent in fatty degenerated liver cells and for renewal of their structure and functions. However, clinical trials are required for more evaluation of the Cu complex in humans. 相似文献