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41.
This paper represents the results of experimental study on the microstructure of uric acid and calcium oxalate crystallites in renal stones. The size distribution parameters and morphological characteristics of the microcrystals forming the stone were determined using SEM and image analysing system. Information on the fabric of the renal stones examined indicates that the mean volume diameter is 15.5 m for uric acid and 32 m for calcium oxalate stones. The polydispersity index , the shape factor , and the distribution of particle shape show close similarity. Quantitative studies on stone microstructure could furnish valuable information on stone genesis.This work was supported by the Kidney Foundation and by the Medical Research Council of Canada. 相似文献
42.
Real-time quantitative RT-PCR and detection of tumour cell dissemination in breast cancer patients: plasmid versus cell line dilutions. 总被引:2,自引:0,他引:2
43.
Despite advancements in endoscopy and pharmacology in the treatment of peptic ulcer disease the overall mortality has remained constant at 10% for the past four decades. The aim of this study was to determine the age, gender, racial distribution, incidence and causes of endoscopically diagnosed cases of upper gastrointestinal (UGI) bleeding to summarise treatments undertaken and to report their outcome. A prospective study of UGI bleeding in 128 patients was performed in two surgical wards of Kuala Lumpur Hospital, involving both elective and emergency admissions. The study group comprised of 113 (88.2%) males and 15 (11.7%) females. The mean age was 51.9 years (range 14 to 85 years) and 37.5% (48 of 128 patients) were older than 60 years. The Indian race was over-represented in all disease categories. Smoking (50.1%), alcohol consumption (37.5%), non-steroidal anti-inflammatory drugs (NSAIDs) (17.2%), traditional remedies (5.5%), anti-coagulants (2.3%) and steroids (0.8%) were among the risk factors reported. Common presenting symptoms and signs included malaena (68.8%), haematemesis (59.4%) and fresh per rectal bleeding (33.6%). The commonest causes of UGI bleeding were duodenal ulcer (32%), gastric ulcer (29.7%), erosions (duodenal and gastric) (21.9%), oesophageal varices (10.9%) and malignancy (3.9%). UGI bleeding was treated non-surgically in 90.6% of cases. Blood transfusions were required in 62.6% (67/107) of peptic ulcer disease patients. Surgical intervention for bleeding peptic ulcer occurred in around 10% of cases and involved under-running of the bleeding vessel in most high risk duodenal and gastric ulcer patients. The overall mortality from bleeding peptic ulcer disease was 4.7%. Six patients died from torrential UGI haemorrhage soon after presentation, without the establishment of a cause. Active resuscitative protocols, early endoscopy, more aggressive interventional therapy, early surgery by more senior surgeons, increasing intensive care unit beds and more active participation of multidisciplinary teams in co-ordinating management are among remedial measures advocated. Broader educational preventive strategies should target the causes of UGI bleeding. 相似文献
44.
Selcen Aydin Piraye Yargicoglu Narin Derin Yakup Aliciguzel Ismail Abidin Aysel Agar 《Food and chemical toxicology》2005,43(7):1093-1101
Stress and sulfite can stimulate numerous pathways leading to an increased production of free radicals which generate a peroxidation cascade producing lipid peroxidation, protein oxidation, DNA damage and cell death, and contribute to the occurrence of pathologic conditions. The purpose of our study was to investigate the effects of stress and sulfite on visual evoked potentials (VEPs) and to examine the relationship between lipid peroxidation and VEP changes. Forty male wistar rats, aged three months were used. They were equally divided into four groups: control (C), the group exposed to restraint stress (R), the group treated with sulfite (S) and the group exposed to stress and treated with sulfite (RS). Chronic restraint stress was applied for 21 days (1h/day) and sodium metabisulfite (520 mg/kg/day) was given by gavage for the same period. All latencies of VEP components were prolonged in the R, S and RS groups with respect to the C group. Brain and retina TBARS levels were found to be increased in those groups compared to the C group. Our results strongly suggest that the latency prolongations of all VEP components may have resulted from the enhancement of lipid peroxidation. Correlation analysis between brain and retina TBARS levels and VEP latencies also support this conclusion. Our data in regard to latency prolongations of all VEP components in the stress group exposed to sulfite, reflected an additive effect of sulfite toxicity on VEP components. Therefore it could be suggested that chronic exposure to stress and sulfite together is associated with a considerable health risk. 相似文献
45.
K Cagdas Kazikdas Bulent Serbetcioglu Ismail Boyraz Kazim Tugyan Guven Erbil Osman Yilmaz Kazim Onal 《Otology & neurotology》2006,27(3):303-307
HYPOTHESIS: The goal of this experimental study was to investigate the specific effect of myringosclerosis on tympanograms in the tympanic membranes of myringotomized rats by using otomicroscopy, tympanometry, and histopathology. BACKGROUND: Myringosclerosis is a common sequela of ventilation tube treatment of otitis media with effusion. The condition involves the hyalinization and calcification of the collagen layer in certain areas of the tympanic membrane. Previous animal experiments suggest an intimate relationship between the formation of myringosclerosis and an increased oxygen concentration in the environment of the wound after myringotomy. The result of a myringotomy therefore is an increased production of free oxygen radicals, initiating irreversible tissue damage involving fibrosis, hyalin degeneration, and finally apoptosis as observed in myringosclerosis. We propose an experimental model specific for creating sclerotic plaques solely on the tympanic membrane and for performing tympanometric measurements on this pure myringosclerosis model without creating any abnormality in the middle ear to test in what proportion myringosclerosis contributes to decrease of amplitude in tympanograms. METHODS: To assess the normal tympanometric values of Wistar albino rats, the pressure and peak admittance of the left middle ears were measured using a semiquantitative computerized clinical admittance meter using a sound frequency of 226 Hz. Twelve animals were randomly selected for the myringotomy group and perforations in the left ears were created. All tympanic membrane perforations in this group had healed and closed prior to the otomicroscopic examination and no pathologic reaction was observed in the external ear canals of rats. Otomicroscopic and tympanometric measurements were carried out on Day 15 and the degree of myringosclerosis was noted before the animals were killed. Twelve specimens in the myringotomy group were histopathologically examined for the presence of myringosclerotic plaques. RESULTS: Under light microscopy, extensive sclerotic lesions were found in the tympanic membranes of the myringotomy group, and these sclerotic deposits were located in the lamina propria. The myringosclerosis occurred predominantly adjacent to the handle of the malleus, but also near the annular region. In all ears with myringosclerosis, the magnitude of the maximum admittance reduced to approximately 50% of the Day-0 values, and this reduction was statistically significant (Z=-3.061, p=0.002). CONCLUSION: The present findings in this study are consistent with the fact that the movement of the tympanic membrane is hampered by lesions of sclerotic material, resulting in a decrease of amplitude in tympanograms (such as Type As) without any effusion or inflammation in the middle ear. 相似文献
46.
Jill K. Schinkel Shelia Hoar Zahm Ismail Jatoi Katherine A. McGlynn Christopher Gallagher Catherine Schairer Craig D. Shriver Kangmin Zhu 《Cancer causes & control : CCC》2014,25(8):959-968
Background
Compared to non-inflammatory breast cancer (non-IBC), inflammatory breast cancer (IBC) has less favorable survival and is more likely to be estrogen receptor (ER) and progesterone receptor (PR) negative. ER?/PR? tumors, regardless of histology, have less favorable survival. While black women are more likely to have IBC and ER?/PR? tumors than white women, it is unclear whether the racial disparity in survival is explained by these factors. The objective of this study was to assess racial/ethnic differences in breast cancer survival by inflammatory status and hormone receptor status.Methods
This study examined breast cancer mortality among non-Hispanic white (NHW), Hispanic white, black, and Asian/Pacific Islander (API) women diagnosed between 1990 and 2004 using the National Cancer Institute’s Surveillance, Epidemiology, and End Results data. Kaplan–Meier survival curves and Cox proportional hazard ratios (HRs) assessed the relationship between race/ethnicity and survival.Results
Black women had significantly poorer survival than NHW women regardless of inflammatory status and hormone receptor status. Compared to NHWs, the HRs for black women were 1.32 (95 % confidence interval (CI) 1.21–1.44), 1.43 (95 % CI 1.20–1.69), and 1.30 (95 % CI 1.16–1.47) for IBC, IBC with ER+/PR+, and with ER?/PR?, respectively. Similar HRs were found for non-IBC, non-IBC with ER+/PR?, and non-IBC with ER?/PR?. API women had significantly better survival than NHW women regardless of inflammatory status and hormone receptor status.Conclusion
Compared to NHW women, black women had poorer survival regardless of inflammatory status and hormone receptor status and API women had better survival. These results suggest that factors other than inflammatory status and hormone receptor status may play a role in racial/ethnic disparities in breast cancer survival. 相似文献47.
Zeinab Salah Seliem Dina Ahmed Mehaney Laila Abd elmoteleb Selim Sonia Ali El-Saiedi Reem Ibrahim Ismail Nihal Magdi Almenabawy Rasha Ibrahim Ammar Inas AbdElsattar Saad Mohammed Mosad Soliman Mohamed A Elmonem 《African health sciences》2022,22(1):200
BackgroundInborn errors of metabolism (IEMs) commonly present with pediatric cardiomyopathy. Identification of the underlying cause is necessary as it may lead to improved outcomes.ObjectivesWe aimed to investigate the diagnostic rate, the clinical, and biochemical spectra of IEMs among Egyptian pediatric patients presenting with cardiomyopathy, and their outcome measures.MethodsWe retrospectively analyzed the clinical, biochemical, and radiological data of 1512 children diagnosed with cardiomyopathy at Cairo University Children''s Hospital over a 5-year duration.ResultsTwo hundred twenty-nine children were clinically suspected as IEMs and underwent metabolic workup. Nineteen different IEMs were confirmed in 57 (24.4%) of the suspected children. Their median age at presentation was 2.6 years and the majority had extra-cardiac manifestations. Hypertrophic cardiomyopathy represented 43/57 (75.4%) of confirmed cases, while dilated cardiomyopathy represented 13/57 (22.8%), and one patient presented with a mixed phenotype. Twenty- six patients (45.6%) survived, while 31 patients (54%) either died or were lost to follow up and assumed deceased.ConclusionsWe developed for the first time a database and a diagnostic scheme for metabolic cardiomyopathies in Egyptian children. With the recent introduction of enzyme replacement therapy, many metabolic disorders became treatable, thus establishing an early and accurate diagnosis is extremely important. 相似文献
48.
A. Alhadhrami Gehad G. Mohamed Ahmed H. Sadek Sameh H. Ismail A. A. Ebnalwaled Abdulraheem S. A. Almalki 《Materials》2022,15(22)
Silica nanoparticles (SiO2 NPs) are one of the most well-studied inorganic nanoparticles for many applications. They offer the advantages of tunable size, biocompatibility, porous structure, and larger surface area. Thus, in this study, a high yield of SiO2 NPs was produced via the chemical treatment of rice husk ash by the sol–gel method. Characteristics of the prepared SiO2 NPs were validated using different characterization techniques. Accordingly, the phase, chemical composition, morphological, and spectroscopic properties of the prepared sample were studied. The average particle size of the SiO2 NPs was found to be approximately 60–80 nm and the surface area was 78.52 m²/g. The prepared SiO2 NPs were examined as photocatalysts for the degradation of methyl orange (MO) dye under UV irradiation. It was found that the intensity of the characteristic absorption band of MO decreased gradually with exposure time increasing, which means the successful photodegradation of MO by SiO2 NPs. Moreover, the antibacterial activity of obtained SiO2 NPs was investigated by counting the coliform bacteria in the surface water using the most probable number (MPN) index method. The results revealed that the MPN of coliform bacteria untreated and treated by SiO2 NPs was estimated to be 170 CFU/100 mL and 10 CFU/100 mL, respectively, resulting in bacterial growth inhibition of 94.12%. 相似文献
49.
50.
Ariff Azfarahim Ibrahim Mohd Ammar Ihsan Ahmad Zamzuri Rosnah Ismail Ahmad Husni Ariffin Aniza Ismail Muhamad Hazizi Muhamad Hasani Mohd Rizal Abdul Manaf 《Medicine》2022,101(30)
The Teleprimary Care—Oral Health Clinical Information System (TPC-OHCIS) is an updated electronic medical record (EMR) that has been applied in Malaysian primary healthcare. Recognizing the level of patient satisfaction following EMR implementation is crucial for assessing the performance of health care services. Hence, the main objective of this study was to compare the level of patient satisfaction between EMR-based clinics and paper-based clinics.The study was a quasi-experimental design that used a control group and was conducted among patients in 14 public primary healthcare facilities in the Seremban district of Malaysia from May 10, to June 30, 2021. Patient satisfaction was assessed using the validated Short-Form Patient Satisfaction Questionnaire, which consisted of 7 subscales. All data were analyzed using the IBM Statistical Package for Social Sciences version 21.A total of 321 patients consented to participate in this study, and 48.9% of them were from EMR clinics. The mean score for the communication subscale was the highest at 4.08 and 3.96 at EMR-adopted clinics and paper-based record clinics. There were significant differences in general satisfaction and communication subscales, with higher patient satisfaction found in clinics using EMR.With the utilization of EMR, patient satisfaction and communication in delivering healthcare services have improved. 相似文献