mohammadali mohammadzadeh
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پودر شیشه یکی از پسماندهای جامد روزافزون در جهان است و از طرفی خاک رس معمولا نیازمند بهسازی جهت استفاده در پروژه های عمرانی می باشد. در تحقیق حاضر اصلاح پارامترهای مقاومتی خاک رس، توسط ژیوپلیمر ساخته شده با پایه پودر شیشه بازیافتی (RGP) مورد مطالعه قرار گرفت. برای این منظور آزمایش های مقاومت تک محوری (UCS) و نسبت باربری کالیفرنیایی (CBR) بروی نمونه های اصلاح شده انجام شد. زمان عمل آوری، درصد وزنی استفاده RGP و غلظت ماده فعال کننده (M) از جمله متغیرهای مورد بررسی در پژوهش بودند.به منظور مقایسه، آزمایشها بروی نمونه های اصلاح شده با 10 درصد سیمان پرتلند نیز انجام گردید. نتایج افزایش ژیوپلیمر به نمونه های خاک نشان داد که میزان استفاده بهینه از RGP مقدار 9 درصد است. همچنین به غیر از نمونه های 0day در آزمایش CBR، سایر نمونه های UCS و CBR دارای مقدار بهینه غلظت ماده فعال کننده (NAOH) بودند که نشان دهنده تاثیر شرایط عمل آوری بر رفتار خاک اصلاح شده است. بررسی تصاویر عکس برداری الکترونی روبشی (SEM) حاکی ازتاثیر روش اصلاحی بر توده خاک بود. مقایسه تحلیلی آزمایش های UCS و CBR بیانگر رابطه ریاضی میان نتایج آزمایش های UCS و CBR-7day با همبستگی نسبی خوب بود که با توجه به شرایط نگهداری یکسان نمونه ها در 7 روز اول قابل انتظار بود. همبستگی اندکی در نتایج آزمایش های UCS و CBR-0day مشاهده شد که علت آن تفاوت شرایط عمل آوری دو آزمایش در 7 روز اول بود.
کلید واژگان: ژئوپلیمر، پودر شیشه بازیافتی، تثبیت خاک رس، نسبت باربری کالیفرنیایی، فعال سازی قلیاییGlass powder is one of the increasing solid wastes in the world and clay usually needs improvement for use in construction projects. In the present study, the modification of the toughness parameters of fine-grained soils was studied by a geopolymer based on recycled glass powder (RGP). For this purpose, uniaxial strength (UCS) and California bearing ratio (CBR) tests were performed on the modified specimens. Processing time, weight percentage of RGP use and activator concentration (M) were among the variables studied in the study. For comparison, experiments were performed on samples modified with 10% Portland cement. The results of increasing the geopolymer to soil samples showed that the optimal use of RGP is 9%. Also, except for the 0day samples in the CBR experiment, other UCS and CBR samples had the optimal amount of activator concentration (NAOH), which indicates the effect of processing conditions on the behavior of the modified soil. Examination of scanning electron imaging (SEM) images showed the effect of the correction method on soil mass. Analytical comparison of UCS and CBR experiments showed a mathematical relationship between the results of UCS and CBR-7day experiments with a good relative correlation that was expected due to the same storage conditions of the samples in the first 7 days. A slight correlation was observed in the results of UCS and CBR-0day tests due to the difference in processing conditions of the two tests in the first 7 days.
Keywords: Geopolymer, Recycled glass powder, Clay stabilization, CBR, alkaline activator -
Following failure of systemic chemotherapy, transarterial chemoembolization (TACE) is an available method to control unresectable liver metastases from colorectal carcinoma (CRC). The aim of present study was to evaluate the efficacy of chemoembolization for inoperable metastatic liver lesions from CRC. Forty-five CRC patients with liver metastases resistant to systemic chemotherapy were enrolled in our study. For each patient, three session of TACE were conducted with 45 days interval. A combination of mitomycin, doxorubicin, and lipiodol were used for TACE. A tri-phasic computed tomography scan and biochemical laboratory tests were performed for all patients at baseline and 30 days after each TACE. Image analysis included measurement of lesion diameters as well as contrast enhancement. Eleven patients deceased before completing three session and the final analyses were performed on the remaining 34 patients. Evaluation of a total 93 lesions in all patients after chemoembolization sessions revealed a 25.88% reduction in anteroposterior (AP) diameter, 33.92% transverse (T) diameter, and 42.22% in product of APxT diameter of lesions (P<0.001 for all instances). CT scan showed a total disappearance of 33% of lesions and evident reduction in contrast enhancement in 16% of them. There were no changes in contrast enhancement in 51% of lesions. Evaluation of single largest lesion in each patient revealed 57.32% reduction in AP diameter, 59.66% in T diameter, and 62.17% in product of APxT diameters (P<0.001 for all diameters). TACE offers a viable option for CRC patients with unresectable liver metastases by significantly reducing lesion size and contrast enhancement.Keywords: Colorectal carcinoma, Liver metastases, Transarterial chemoembolization, Chemotherapy
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The use of noninvasive assessment tools such as multi-slice CT coronary angiography (MSCT-CA-CA) is recently considered mainly because it offers safety, patient convenience, and faster performance. The aim of the present study was to determine the ability of MSCT-CA-CA for the detection of significant stenoses in the coronary arteries, in comparison to conventional invasive coronary angiography (ICA). A total of 58 consecutive patients who were candidate for coronary angiography, with the diagnosis of acute coronary syndrome, from September 2006 to March 2006 were entered into the study. They underwent both coronary MSCT-CA-CA and ICA. The findings of each coronary segment were compared to MSCT-CA-CA in comparison with ICA. Based on artery analysis, sensitivity and specificity of MSCT-CA for the detection of involvement in RCA were 90.0% and 92.8%, in LAD were 71.8% and 92.9% and in LCX were 67.9% and 92.6%, respectively. On a per-segment basis, the sensitivity of MSCT-CA in the detection of injured segments ranged between 33.3% (for segment 11) and 100% (for segments 1, 2 and 12). Also, specificity ranged from 63.6% (for segment 15) and 98.1% (for segment 6). The presence of hypertension, hyperlipidemia, and smoking led to the reduction of the specificity and accuracy of MSCT-CA, whereas history of diabetes mellitus could increase the specificity and accuracy of this tool. MSCT-CA has high diagnostic performance in the assessment of significant coronary artery disease. Risk factors for coronary artery disease may influence this performance.
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مقدمهرعایت استاندارد های بیهوشی از ضروریات بوده و لازم است قبل، حین و در خاتمه روند بیهوش کردن بیماران وضعیت موجود طبق چک لیست استانداردی ارزیابی شود و در صورت وجود مشکل، راه حل منطقی ارائه گردد. هدف این مطالعه طراحی چک لیست ارزیابی میزان رعایت استانداردهای بیهوشی و بررسی وضع موجود مراعات استانداردها توسط متخصصین و رزیدنت های بیهوشی در بیمارستان های دانشگاه علوم پزشکی گیلان می باشد.روش هاابتدا مراحل مختلف فرآیند بیهوش کردن بیمار از هنگام ورود به اتاق عمل تا زمان خروج وی مشخص گردید. در هر مرحله استانداردها بر اساس کتاب های معتبر و نظریه های اصلاحی اخذ شده از اساتید بیهوشی و با توجه به شرایط موجود بیمارستان های دانشگاه مربوطه تدوین و چک لیست آن استخراج گردید. فعالیت متخصصین و رزیدنت های بیهوشی (20 نفر) بر اساس چک لیست فوق به صورت غیر محسوس در طی 6 ماه مشاهده و ارزیابی شد. داده ها با محاسبه توزیع فراوانی تحلیل گردید.نتایجبیشترین موارد عدم رعایت استاندارد به ترتیب نزولی مربوط بودند به: آماده سازی اتاق عمل (5/52 درصد)، قبل از انتوباسیون (2/42 درصد)، قبل از اکستوباسیون (40 درصد)، حین بیهوشی (5/34 درصد)، ترخیص از ریکاوری (3/33 درصد)، بعد از انتوباسیون (7/27 درصد)، قبل از ریکاوری (2/27 درصد)، حین ریکاوری (1/17 درصد)، هنگام انتوباسیون (8/13 درصد)، هنگام ورود بیمار به ریکاوری (3/11 درصد)، تحویل بیمار به ریکاوری(10 درصد)، موقع اکستوباسیون (9 درصد)، بعد از اکستوباسیون (0 درصد).نتیجه گیریضرورت داشتن چک لیست و بکارگیری آن در زمان بیهوش کردن بیماران در اتاق عمل برای حفاظت بیمار از خطرات با این مطالعه مشخص و نقاط ضعف عملکرد کنونی مشخص گردید. بر اساس نتایج مطالعه حاضر می توان مداخلات آموزشی و مدیریتی برای بهبود مراعات استانداردها را طراحی نمودکلید واژگان: بیهوشی، استانداردهای بیهوشی، مراقبت بعد از بیهوشی، راهنمای آموزشی، درمانی، ارزیابیIntroductionApplying basic standards of anesthesia care is crucial. Patients’ status should be evaluated based on a standard checklist. In case of mismanagement, logical approaches must be conducted. The main objective of the present study is to develop a checklist for evaluation of implementing anesthesia care standards, and its application by observing the practice of anesthesiologists and their residents in Guilan Medical University hospitals.MethodsAt first, different stages of anesthesia from patients’ arrival to the operating room till discharge from the recovery room were determined. In every stage, standard protocols were prepared. Then, the checklist items were developed based on anesthesia reference books and the modifications made according to Guilan anesthesiologists and conditions of university hospitals. After that, the adherence of twenty anesthesiologists and residents to these protocols were insensibly observed and scored for six months. Data were analyzed and frequency distribution was presented.ResultsRate of not-applied standards in descending orders was: 52.5% in preparation of operating room, 42.2% in pre-intubation, 40% in pre-extubation, 34.5% during maintenance of anesthesia,33.3% at discharge from the recovery room, 27.7% after intubation, 27.2% before arrival to the recovery room, 17.1% in recovery room, 13.8% at the time of intubation, 11.3% at arrival to the recovery room, 10% upon admission to the recovery room, 9% upon extubation, and 0% after extubation.ConclusionThis study revealed the necessity of using standard checklist for anesthesia care in operating room to protect the patient and to decrease the risk of anesthesia for them. Based on the results, educational and management interventions should be designed to promote adherence to standards.
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Trauma Monthly, Volume:16 Issue: 4, Jan-Feb2011, PP 160 -163Background
Arterial damage is sometimes associated with supracondylar fractures of the humerus. Diagnosis and careful management of the fracture and arterial repair is crucial.
ObjectivesThe aim of this study was to determine the prevalence and outcome of supracondylar fractures of the humerus with signs and symptoms of limb ischemia, before and after arterial decompression or arterial reconstruction.
Materials and MethodsFrom September 2004 to July 2010, 225 consecutive patients with supracondylar fracture of the humerus were prospectively recruited.
ResultsFrom among 75 cases with Gartland type III fractures, 22 were found to have vascular injury.. Of the 22 cases with vascular injury, 7 patients underwent arterial reconstruction. The other 15 received arterial decompression. All patients had a satisfactory outcome.
ConclusionsA high level of suspicion and careful clinical evaluation leading to an early diagnosis and management of vascular injury accompanying supracondylar fracture is very important to prevent unnecessary sequelae ranging from limb claudication, and compartment syndrome to more severe complications like Volkmann’s contracture and even limb loss.
Keywords: humerus, Fractures, Bone
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