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991.
Robman L Mahdi OS Wang JJ Burlutsky G Mitchell P Byrne G Guymer R Taylor H 《Investigative ophthalmology & visual science》2007,48(9):4007-4011
PURPOSE: To assess cross-sectional and longitudinal associations between exposure to Chlamydia pneumoniae infection and age-related macular degeneration (AMD) in the nested case-control sample drawn from the Blue Mountains Eye Study (BMES) cohort. METHODS: The BMES examined 3654 persons aged 49 to 97 years during 1992 through 1994 (BMES I survey). Survivors from this cohort (n = 2335; 75%) and 1174 persons who moved in this area or reached an eligible age were examined during 1997 through 2000 (BMES II survey, n = 3509). One hundred ninety-seven AMD cases and 433 control subjects matched for age, sex and smoking status, were drawn from the BMES II survey. Photographic macular grading followed the Wisconsin grading system. Plasma samples were analyzed with an enzyme-linked immunosorbent assay to determine antibody titers to the elementary bodies from C. pneumoniae AR39. Associations between seroreactivity to C. pneumoniae and prevalent and incident AMD were assessed by using logistic regression models. RESULTS: There were 159 early and 38 late AMD cases. Of them, 87 cases of early and 22 of late AMD developed between the baseline and follow-up examinations. After adjustment for age, gender, and smoking, no significant association was evident between C. pneumoniae antibody titer and any prevalent early or late AMD (OR 1.02, 95% CI 0.66-1.56 comparing upper with lower tertile of antibody titer). Findings were similar when early or late AMD was analyzed separately. Analysis confined to incident AMD also showed no significant association with the incidence of either early (OR 0.92, 95% CI 0.52-1.64) or late (OR 1.85, 95% CI 0.57-6.05) AMD. The results did not change after adjustment for family history of AMD and cardiovascular disease. CONCLUSIONS: In this nested case-control sample of an older Australian population we found no association between C. pneumoniae antibody titers and early AMD. The study has insufficient power to assess an association with late AMD. 相似文献
992.
Hashem Shemshadi Mojtaba Azimian Ali Mohammad Onsori Mahdi AzizAbadi Farahani 《BMC ear, nose, and throat disorders》2008,8(1):1-6
Background
To assess the importance of different information pathways for patients undergoing elective ENT surgery (General Practitioner, Specialist consultation, pre assessment clinic and consent process as well as printed information material and non medical sources) and to correlate their relative importance with patient and doctor factorsMethods – Patients
Cross – sectional questionnaire survey 226 consecutive patients undergoing elective non-oncological otolaryngology procedures at a District General Hospital between May and August 2004Results
Overall patients were moderately satisfied with the information they received prior to surgery (score 63/100). Although they were generally satisfied with the quality of information they received at their outpatient consultation and at the preadmission clinic, they were less satisfied with the quality of information provided by their GPs and by the quality of self – obtained information. Most importantly, linear regression modeling showed that the overall level of information could be predicted by three factors: The quality of written information received at the hospital, the quality of self-obtained information and the information provided by the specialist at the time of listing for surgery. While patient's education level was correlated with the information process, the age and gender of the patient as well as the grade of the doctor at the outpatients were not associated with his overall levels of satisfaction.Conclusion
Although the impact of the initial outpatient consultation for patients undergoing elective surgery can not be over emphasized, written information provided at the hospital as well as patient – initiated, parallel information pathways are at least as important: It is our duty to recognize them and use them for the patient's advantage. 相似文献993.
Aflatoxins are secondary metabolites that are produced by toxigenic strains of some Aspergillus species on foods. Neem plant is a known inhibitor of aflatoxin production. We studied the effects of different concentrations of aqueous neem leaf extract on fungal growth and aflatoxin production by Aspergillus parasiticus (NRRL 2999) at different incubation times. The toxigenic fungus was cultured on sucrose low salts medium in the presence of various concentrations of extracts (0.2, 0.8, 3.12, 12.5 and 50% v/v). After shaking incubation of cultures for 2, 4, 6, 8, 10 and 12 days at 28 degrees C, the fungal mycelia was collected and processed for determination of dry weight. Mycelia and culture media were assayed by TLC method to detect aflatoxin B(1) (AFB(1)). The extracts did not have any obvious effect on fungal growth. AFB(1) production in the control samples increased to the maximum level on the 8th day. The inhibition of aflatoxin synthesis by plant extracts was found to be time- and dose-dependent. The maximum inhibitory effect was 80-90% in the presence of 50% concentration that when compared with control samples was significant (P < 0.05). AFB(1) secretion/production ratio in all of control and treated samples, other than 2nd day, approximately stayed and neem had no effect on it. 相似文献
994.
995.
Alireza Karimi Mahdi Navidbakhsh Hiroshi Yamada Reza Razaghi 《Medical & biological engineering & computing》2014,52(7):589-599
The stresses induced on plaque wall during stent implantation inside a stenotic artery are associated with plaque rupture. The stresses in the plaque–artery–stent structure appear to be distinctly different for different plaque types in terms of both distribution and magnitude. In this study, a nonlinear finite element simulation was executed to analyze the influence of plaque composition (calcified, cellular, and hypocellular) on plaque, artery layers (intima, media, and adventitia), and stent stresses during implantation of a balloon expandable coronary stent into a stenosed artery. The atherosclerotic artery was assumed to consist of a plaque and normal arterial tissues on its outer side. The results revealed a significant influence of plaque types on the maximum stresses induced within plaque wall and artery layers during stenting, but not when calculating maximum stress on stent. The stress on stiffer calcified plaque wall was in the fracture level (2.21 MPa), whereas cellular and hypocellular plaques play a protective role by displaying less stress on their wall. The highest von Mises stresses were observed on less stiff media layer. The findings of this study suggest a lower risk of arterial vascular injury for calcified plaque, while higher risk of plaque ruptures for cellular and hypocellular plaques. 相似文献
996.
Mahdi Jalili Reto Meuli Kim Q. Do Martin Hasler Timothy J. Crow Maria G. Knyazeva 《Psychophysiology》2010,47(4):706-716
The interhemispheric asymmetries that originate from connectivity‐related structuring of the cortex are compromised in schizophrenia (SZ). Under the assumption that such abnormalities affect functional connectivity, we analyzed its correlate—EEG synchronization—in SZ patients and matched controls. We applied multivariate synchronization measures based on Laplacian EEG and tuned to various spatial scales. Compared to the controls who had rightward asymmetry at a local level (EEG power), rightward anterior and leftward posterior asymmetries at an intraregional level (1st and 2nd order S‐estimator), and rightward global asymmetry (hemispheric S‐estimator), SZ patients showed generally attenuated asymmetry, the effect being strongest for intraregional synchronization in the alpha and beta bands. The abnormalities of asymmetry increased with the duration of the disease and correlated with the negative symptoms. We discuss the tentative links between these findings and gross anatomical asymmetries, including the cerebral torque and gyrification pattern, in normal subjects and SZ patients. 相似文献
997.
Mahdi Selim Hany Mowafi Abdulmohsen Al-Ghamdi Yaw Adu-Gyamfi 《Journal canadien d'anesthésie》1999,46(9):891-893
PURPOSE: To report two cases of successful tracheal intubation in difficult pediatric airways using a conventional laryngeal mask airway (LMA) with an extended polyvinyl chloride (PVC) tube after laryngeal assessment with a fibreoptic device. CLINICAL FEATURES: Two cases, Dandy-Walker and Pierre Robin syndromes, were scheduled for surgery. They were premedicated with 0.5 mg x kg(-1) promethazine p.o. 90 min before surgery. Both patients arrived in the operating room sedated, with dry mouth, and without evidence of increased intracranial tension or airway obstruction. Inhalational induction with isoflurane 0.5-3% was commenced. Conventional tracheal intubation was impossible in both cases. In each an LMA was inserted to maintain ventilation, anesthesia, and to facilitate intubation. Fibreoptic bronchoscopy was used to assess the larynx, followed by blind intubation via the LMA using extended PVC tracheal tube (TT). Anesthesia was maintained during intubation using Mapleson F anesthesia circuit attached to a connector with fibreoptic bronchoscope adapter. CONCLUSION: This report describes the assessment of the airway with fibreoptic bronchoscopy after LMA insertion facilitated blind tracheal intubation in two children with difficult airways. 相似文献
998.
Amir Ghiasvand Mohammad Mahdi Yavari Jacek Tomkw John William Grimaldo Guerrero Hasan Kheradmandan Aleksei Dorofeev Shabbir Memon Hesamoddin Aghajani Derazkola 《Materials》2021,14(20)
The present study investigates the effect of two parameters of process type and tool offset on tensile, microhardness, and microstructure properties of AA6061-T6 aluminum alloy joints. Three methods of Friction Stir Welding (FSW), Advancing Parallel-Friction Stir Welding (AP-FSW), and Retreating Parallel-Friction Stir Welding (RP-FSW) were used. In addition, four modes of 0.5, 1, 1.5, and 2 mm of tool offset were used in two welding passes in AP-FSW and RP-FSW processes. Based on the results, it was found that the mechanical properties of welded specimens with AP-FSW and RP-FSW techniques experience significant increments compared to FSW specimens. The best mechanical and microstructural properties were observed in the samples welded by RP-FSW, AP-FSW, and FSW methods, respectively. Welded specimens with the RP-FSW technique had better mechanical properties than other specimens due to the concentration of material flow in the weld nugget and proper microstructure refinement. In both AP-FSW and RP-FSW processes, by increasing the tool offset to 1.5 mm, joint efficiency increased significantly. The highest weld strength was found for welded specimens by RP-FSW and AP-FSW processes with a 1.5 mm tool offset. The peak sample of the RP-FSW process (1.5 mm offset) had the closest mechanical properties to the base metal, in which the Yield Stress (YS), ultimate tensile strength (UTS), and elongation percentage (E%) were 76.4%, 86.5%, and 70% of base metal, respectively. In the welding area, RP-FSW specimens had smaller average grain size and higher hardness values than AP-FSW specimens. 相似文献
999.
Farideh Jowkar Motahhareh Hosseini Kahnooj Fatemeh Sari Aslani Mohammad Mahdi Parvizi 《Dermatologic therapy》2020,33(3)
The aim of the present study was to investigate the clinical association between rippled pattern pigmentation and the positivity of histopathological analysis for amyloid. A total of 50 patients (90% women) with rippled pattern pigmentation referring to Dermatology Clinic of Shahid Faghihi Hospital, Shiraz, Iran, in 2015 participated in this study. Two biopsies were performed for all the cases from the most frequently affected sites. The specimens were evaluated for amyloid deposits with hematoxylin–eosin (H&E), Congo red (CR), and crystal violet (CV) stains. The upper back was the most frequently affected area in the patients. Family history (28%), atopy (14%), pruritus as a common finding (86%), and history of friction (54%) were positive. The prevalence of disease was higher in patients with skin photo Type 3. Amyloid deposit was not detected in most patients by these stains. No statistically significant difference was found between the amyloid positive cases stained with H&E, CR, and CV (p‐value > 0.05). Only the difference in positive results between biopsy number 2 and the total biopsy (1 and 2) was significant (p‐value < .05). In conclusion, it seems that it is useful to increase the number of biopsies and other more sensitive staining methods to detect small focal amyloid deposits. 相似文献
1000.
Davood Mohammadi Yazdan Zafari Zohreh Estaki Mahdi Mehrabi Sahar Moghbelinejad 《Journal of clinical laboratory analysis》2022,36(1)
BackgroundNowadays, non‐invasive and rapid detection of cancers through molecular biomarkers has received much attention. Therefore, this study investigated the non‐invasive and rapid diagnosis of colorectal cancer through one of the newest biomarkers (circular RNA).MethodsFor this purpose, we collected tumoral, adjacent normal tissue, and plasma samples from 100 colorectal cancer (CRC) patients, 25 postoperative CRC patients, 28 colitis patients, and 108 healthy donors. First Illumina high‐throughput (Hi Seq 2000) sequencing was performed to identify known and novel differentially expressed circRNAs in the cancerous and adjacent normal tissues (n = 3). We used quantitative real‐time fluorescent polymerase chain reaction (qRT‐PCR) to detect the expression level of hsa_circ_0006282 among the different samples. Moreover, inter‐ and intra‐assays were performed to evaluate the potential of hsa_circ_0006282 as being a biomarker. The receiver operating characteristic curve (ROC) was drawn to appraise its diagnostic efficacy, and the sensitivity of this circ RNA was evaluated.ResultsBased on RNA‐sequencing results circ_0006282, cirs7, circ‐0001313, circ_0055625, circ_000984, circ_0055625, circ_0001178, circ_0071589, circ‐001569 were upregulated, and circ‐ITGA7, circ‐CDYL, circITCH, circ_0026344, circ_0000038, circ_0002220, circ_0067480, circIGHV3‐20‐1, circ_104916, circ_0009361 were downregulated circRNA. The hsa_circ_0006282 was the highest upregulated differentially expressed circRNA. Expression evaluation of this circRNA on different samples showed upregulation in CRC tissues (p < 0.0001) and plasma samples of CRC patients in comparison to healthy controls (p < 0.0001), while the area under the curve (AUC) was 0.831 (95% CI: 0.779–0.883). Expression of hsa_circ_0006282 in CRC patients decreased to normal after surgery (p < 0.0001). Our results showed high specificity and sensitivity of CRC detection when hsa_circ_0006282, carcinoembryonic antigen (CEA), and carbohydrate antigen199 (CA199) are combined.ConclusionPlasma hsa_circ_0006282 can be used as a novel diagnostic and dynamic monitoring biomarker in CRC patients. 相似文献