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101.
Khawaja Afzal Ammar Ravindrakumar Makwana Steven J. Jacobsen Jan A. Kors John C. Burnett Margaret M. Redfield Barbara P. Yawn Richard J. Rodeheffer 《Annals of noninvasive electrocardiology》2007,12(1):27-37
Background: The relationship between electrocardiographic unrecognized myocardial infarction (UMI), abnormal functional status, echocardiographic abnormalities, and mortality has not been evaluated. Methods: A population‐based random sample of 2042 Olmsted County residents, age ≥45 years, was studied by self‐administered questionnaire, chart review, ECG and echocardiogram, and 5 year follow‐up for all‐cause mortality. UMI (n = 81) was diagnosed if ECG‐MI criteria were met without previous documented myocardial infarction. Functional Status was assessed by the Goldman Specific Activity Scale. Results: UMI subjects had an increased prevalence of abnormal functional status compared to no MI controls (22% vs 11%, P < 0.05). This association was independent of sex, obesity, smoking, diabetes, and pulmonary disease. It became insignificant after stratifying for echocardiographic abnormalities. Compared to no MI controls, UMI subjects with impaired functional status had a higher mortality hazard ratio (HR 7.2; P<0.0001) than those without impaired functional status (HR 2.7; P = 0.02). In UMI subjects with impaired functional status and any echocardiographic abnormality signifying global ventricular dysfunction (systolic or diastolic dysfunction, left atrial or left ventricular enlargement), the mortality risk was even higher (HR 9.5; P<0.001) and persisted in multivariate analyses. This increased mortality risk was unaffected by adjustment for regional wall motion abnormalities. Conclusions: The assessment of impaired functional status and echocardiographic abnormalities improves the prognostic significance of UMI. Even in the absence of regional wall motion abnormalities, structural abnormalities of global dysfunction may play a role in mediating the increased mortality associated with UMI. 相似文献
102.
Shahid M Hameed K Iqbal R Afzal O Nakeer R Razzak J 《Journal of the College of Physicians and Surgeons--Pakistan : JCPSP》2012,22(5):342-343
An indicator for emergency room performance is the ability to establish the correct diagnosis within the emergency room over the years. The authors chose to examine the non-congruence of Emergency Room diagnoses to that established after hospital stay for three selected years. A total of 8488 records were reviewed and all disparate diagnosis were recorded and categorized. Retrospective chart reviews were done from July 2008 to February 2009 at the Aga Khan University Hospital, Karachi. A substantial reduction in the percentage of disparate diagnoses was seen over the years from 41% in the initial year to 14% in the last year evaluated. It was concluded that over the years there has been an improvement in the reliability of Emergency Room diagnoses at the Aga Khan University Hospital, Karachi. 相似文献
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Endoluminal gastroplication in children with significant gastro-oesophageal reflux disease 总被引:1,自引:0,他引:1 下载免费PDF全文
AIMS: To describe paediatric experience, and to assess complications and therapeutic effectiveness of the use of endoluminal gastroplication in children with gastro-oesophageal reflux disease (GORD) refractory to, or dependent on, proton pump inhibitors. METHODS: Seventeen (five male) consecutive children/adolescents (median (range) age 12.4 (6.1-15.9) years, median (range) weight 46.0 (16.5-87.5) kg) with GORD either dependent for more than 12 months on proton pump inhibitors or non-responsive to medical treatment underwent endoscopic gastroplication using a flexible endoscopic sewing device (EndoCinch). Three plications were placed in gastric tissue below the lower oesophageal sphincter. Drug dose requirement, pH measurements, daily symptom severity and frequency, and validated reflux (QOLRAD) and general gastrointestinal (GSRS) quality of life scores were compared before and after endoscopic gastroplication. RESULTS: All patients showed post-treatment improvement in symptom severity, frequency, and quality of life scores (p<0.0001). Three patients with recurrent symptomatic GORD had a repeat procedure within six weeks and did well subsequently. At up to 33 months of follow up (median 23), 14/17 patients remained off all antireflux medications, and 14/17 had maintained their symptomatic improvement. All pH parameters improved and had returned to normal values in 14/16 patients post-treatment and in 6/9 after one year of follow-up: in particular the reflux index had decreased from a median of 16.6% (0.9-67%) to 2.5% (0.7-15.7%) (p<0.0001) six weeks and 4.3% (2.2-20.6) (p<0.02) 12 months post-procedure. The only complication observed was gastric bleeding in one patient due to previously undiagnosed coagulopathy, which spontaneously resolved. CONCLUSIONS: Endoluminal gastroplication is an effective and safe procedure in children/adolescents with significant GORD refractory to, or dependent on, medical anti-GORD therapy. 相似文献
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108.
Kolbach AM Afzal O Halligan B Sorokina E Kleinman JG Wesson JA 《Urological research》2012,40(5):447-454
We have tested the relative electrophoretic mobility of osteopontin (OPN) isolated from urine obtained from normal individuals (NU) against similar samples derived from the urine of stone formers (SFU) using high-resolution isoelectric focusing (isoelectric point, pI range 3.5-4.5) in 2D electrophoresis, with Western blot detection. We also report the results from competitive ELISA analyses of these samples. We demonstrated that human urinary OPN has a discrete four band separation pattern that conforms to four previously documented OPN isoforms. The lower two M(r) isoforms migrate to a greater degree toward the acidic end of the gel than do the higher two M(r) isoforms. Densitometry of the signal reveals significant difference in the migration pattern of OPN from SFU as compared to that from NU based on an analysis of the spot intensities grouped in 0.1?pI unit increments. A novel method for the calculation of a weight-averaged pI based on the relative signal strength in an OPN 2D Western blot was developed. The analysis revealed a significantly increased weight-averaged pI values for the higher M(r) forms of OPN in the stone former compared to normal population. Additionally, alkaline phosphatase-treated NU samples resulted in a significant average pI shift of 0.05?units in the alkaline direction, suggesting that a decrease in the average degree of phosphorylation could be responsible for the difference between NU and SFU pI. 相似文献
109.
Mohammed Najeeb Al-Hashem Muhammad Nasir Amin Ali Ajwad Muhammad Afzal Kaffayatullah Khan Muhammad Iftikhar Faraz Muhammad Ghulam Qadir Hayat Khan 《Materials》2022,15(22)
Due to the increasing prices of cement and its harmful effect on the environment, the use of cement has become highly unsustainable in concrete. There is a considerable need for promoting the use of cement replacement materials. This study investigates the effect of variable percentages of metakaolin (MK) on the mechanical and durability performance of concrete. Kaolin clay (KC) was used in the current research to prepare the MK by the calcination process; it was ground in a ball mill to its maximum achievable fineness value of 2550 m2/Kg. Four replacement levels of MK, i.e., 5%, 10%, 15%, and 20% by weight of cement, in addition to control samples, at a constant water-to-cement (w/c) ratio of 0.55 were used. For evaluating the mechanical and durability performance, 27 cubes (6 in. × 6 in. × 6 in.) and 6 cylinders (3.875 in. diameter, 2 in. height) were cast for each mix. These samples were tested for compressive strength under standard conditions and in an acidic environment, in addition to being subjected to water permeability, sorptivity, and water absorption tests. Chemical analysis revealed that MK could be used as pozzolana as per the American Society for Testing and Materials (ASTM C 618:2003). The results demonstrated an increased compressive strength of concrete owing to an increased percentage of MK in the mix with aging. In particular, the concrete having 20% MK after curing under standard conditions exhibited 33.43% higher compressive strength at 90 days as compared to similarly aged control concrete. However, with increasing MK, the workability of concrete decreased drastically. After being subjected to an acid attack (immersing concrete cubes in 2% sulfuric acid solution), the samples exhibited a significant decrease in compressive strength at 90 days in comparison to those without acid attack at the same age. The density of acid attack increased with increasing MK with a maximum corresponding to 5% MK concrete. The current findings suggest that the local MK has the potential to produce good-quality concrete in a normal environment. 相似文献
110.
Attia Hamid Asma Zafar Sabahat Latif Liangcai Peng Yanting Wang Iram Liaqat Muhammad Sohail Afzal Ikram ul-Haq Muhammad Nauman Aftab 《RSC advances》2023,13(2):1434
A low temperature alkali (LTA) pretreatment method was used to treat wheat straw. In order to obtain good results, different factors like temperature, incubation time, NaOH concentration and solid to liquid ratio for the pretreatment process were optimized. Wheat straw is a potential biomass for the production of monomeric sugars. The objective of the current study was to observe the saccharification (%) of wheat straw with immobilized magnetic nanoparticles (MNPs). For this purpose, immobilized MNPs of purified β-xylanase enzyme was used for hydrolysis of pretreated wheat straw. Wheat straw was pretreated using the LTA method and analyzed by SEM analysis. After completion of the saccharification process, saccharification% was calculated by using a DNS method. Scanning electron micrographs revealed that the hemicellulose, cellulose and lignin were partially removed and changes in the cell wall structure of the wheat straw had caused it to become deformed, increasing the specific surface area, so more fibers of the wheat straw were exposed to the immobilized β-xylanase enzyme after alkali pretreatment. The maximum saccharification potential of wheat straw was about 20.61% obtained after pretreatment with optimized conditions of 6% NaOH, 1/10 S/L, 30 °C and 72 hours. Our results indicate the reusability of the β-xylanase enzyme immobilized magnetic nanoparticles and showed a 15% residual activity after the 11th cycle. HPLC analysis of the enzyme-hydrolyzed filtrate also revealed the presence of sugars like xylose, arabinose, xylobiose, xylotriose and xylotetrose. The time duration of the pretreatment has an important effect on thermal energy consumption for the low-temperature alkali method.A low temperature alkali (LTA) pretreatment method was used to treat wheat straw. 相似文献