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11.

Objective:

The outcome of post-surgical recurrences of cervical cancer may be improved through radiation dose escalation, which hinges on accurate identification and treatment of the target. The present study quantifies target motion during course of image-guided radiotherapy (IGRT) for vault cancers.

Methods:

All patients underwent planning CT simulation after bladder-filling protocol. A daily pre-treatment megavoltage CT was performed. All translations and rotations were recorded. Post-registration displacement of gross tumour volume (GTV) and centre of mass (COM) of GTV was independently recorded by two observers for fractions one to seven. Day 1 image sets served as reference images against which the displacements of COM were measured. We calculated the displacements of common volume (CV) and encompassing volume (EV) of GTV for both the observers.

Results:

A total of 90 image data sets of 15 patients were available for evaluation. Individual patient GTV and average GTV by both the observers were comparable. The average shifts for EV were 2.4 mm [standard deviation (SD) ±1.2] in the mediolateral, 4.2 mm (SD ±2.8) in the anteroposterior and 4.0 mm (SD ±2.1) in superoinferior directions. Similarly, the average shifts for CV were 1.9 mm (SD ±0.6) in the mediolateral, 3.7 mm (SD ±2.7) in the anteroposterior and 4.4 mm (SD ±2.7) in superoinferior directions. Using Stroom''s/van Herk''s formula, the minimum recommended margins would be 4.5/5.2, 8.2/9.4 and 7.3/8.3 mm, respectively, for lateral, anteroposterior and superoinferior directions.

Conclusion:

Differential directional internal margin is recommended in patients undergoing IGRT for post-surgical recurrence of cervical cancers.

Advances in knowledge:

Internal organ motion of vault cancers can be accounted for by a directional margin to the gross tumour.  相似文献   
12.
Indwelling central venous catheters have been reported to increase the risk of superior venous cava (SVC) syndrome. This case report describes the development of acute SVC syndrome in a 28‐year‐old woman with end‐stage renal disease implanted with a left‐side hemodialysis reliable outflow graft and a right‐side double lumen hemodialysis catheter via internal jugular veins. Her symptoms were not alleviated after catheter removal and systemic anticoagulation therapy. She was eventually treated with catheter‐directed thrombolysis and a predischarge computer tomographic venogram on postthrombolytic procedure day 7 showed patent central veins and patient remained asymptomatic. This case demonstrates that catheter‐directed thrombolysis can be safely employed to treat refractory catheter‐induced acute SVC syndrome in end‐stage renal disease patients.  相似文献   
13.
Gallstone disease is a common gastrointestinal problem in day-to-day practice. The Old concept that a typical gallstone sufferer is fat, fertile, flatulent female of 50. This is partially true as the disease has been found in women soon after their first delivery who are thin and underweight and in males also. Conditions that favor the formation of cholesterol gallstones are super saturation of bile with cholesterol, kinetically favorable nucleation and presence of cholesterol crystals in the gall bladder long enough to agglomerate into a stone. Recent studies have defined the role of trace elements (Fe, Ca, Zn and Cu) and defective pH in the formation of gallstones. The aim of the study was to correlate iron-deficiency anemia with gallstone disease. To estimate the serum ferritin level as a diagnostic tool of iron deficiency anemia in patients with gallstone disease, this prospective study of 100 patients was conducted over a period of 24 months in the Department of General Surgery, Jaipur Golden Hospital, New Delhi, India. Serum cholesterol, iron and ferritin levels were compared in patients having gallstones and healthy individuals. A low serum iron level is a factor in bile super saturation with respect to cholesterol, leading to gallstone formation.  相似文献   
14.
15.
目的 研究GPC5基因在肺腺癌细胞系中的表达情况及其对肺腺癌细胞系生物学行为的影响.方法 采用逆转录PCR (RT-PCR)、实时定量PCR (qRT-PCR)以及Western blot分析肺腺癌细胞系中GPC5基因mRNA及蛋白表达情况;构建GPC5过表达载体及干扰载体,通过转染构建GPC5过表达细胞系及GPC5沉默细胞系;利用CCK-8法分析肺腺癌细胞系生长情况;通过流式细胞术检测肺腺癌细胞系的周期及凋亡变化.结果 检测了GPC5基因在4株肺腺癌细胞系(A549、H1299、H358和H1975)和1株肺正常上皮细胞系(HBE)中的mRNA表达情况,发现与HBE细胞系相比,GPC5基因在A549细胞系中呈低表达,在H1299细胞系中高表达,同时蛋白检测结果与mRNA水平一致;A549细胞中过表达GPC5基因可抑制细胞生长,引起细胞周期阻滞;在H1299细胞中干扰GPC5基因表达促进细胞生长,促进细胞周期;在过表达和干扰细胞模型中均未发现GPC5基因对细胞凋亡的显著影响.结论 GPC5基因可以对肺腺癌细胞系的生物学行为产生影响,可能是肺腺癌的抑癌基因.  相似文献   
16.

Purpose

Avascular necrosis (AVN) of the femoral head is a common orthopaedic disease that is difficult to treat. The purpose of this study was to explore the preliminary efficacy of a self-designed umbrella-shaped memory alloy femoral head support device in the treatment of adult patients with avascular osteonecrosis of the femoral head.

Methods

The minimally-invasive approach involved curettage of the necrotic tissue of the femoral head, and a self-designed umbrella-shaped, memory alloy femoral head support device was implanted into the collapsed necrotic area to support the collapsed femoral head. Autologous iliac bone and artificial bone were implanted into the support device for the treatment of adult patients with avascular osteonecrosis of the femoral head.

Results

The clinical device was used in ten patients and 18 hip joints. The support device failed in one hip joint, which subsequently underwent joint replacement surgery, and the remaining 17 implanted devices were followed up for four to 19 months. The 17 postoperative hip joints were evaluated using the percent-efficacy evaluation method for avascular osteonecrosis of the femoral head in adult patients, and the efficacy rate was 82.35 %.

Conclusion

The umbrella-shaped femoral head support device can be used in Ficat stage I, stage II, and stage III adult patients with avascular osteonecrosis of the femoral head.  相似文献   
17.
18.
In covering the Emergency Department, the Plastic Surgeon can be faced with the mandibular fracture patient. Although the timely repair of the fracture usually leads to normal function and appearance, occasionally the surgeon is faced with the untoward sequelae of the mandible fracture. Post-traumatic mandibular deformities include non-union, malunion, malocclusion, TMJ dysfuction, and facial asymmetry. The difficulty in treatment of these deformities can be compounded by edentulous mandibles, substance abuse, and approach controversies such as the timing of the repair and surgical versus non-surgical management. Knowledge of the post-traumatic mandibular deformities by the treating physician not only assists in their management but may also allow for their prevention.  相似文献   
19.
INTRODUCTION: Patients presenting to the Accident and Emergency department of a district general hospital with an eye problem are referred directly to a dedicated eye casualty service. They are then triaged by a staff nurse from the eye department. This eye casualty sees around 8000 patients per annum. This study assesses whether the nurse triage of eye casualty patients forms an effective filter of problems which do not require the attention of the doctor on duty. The incidence of cases of misdiagnosis and inappropriate discharge of patients resulting in a delay in diagnosis and treatment was also assessed. METHODS: All patients presenting in a 3-month period managed solely by the triage nurse, were identified from the casualty register, and the hospital records retrieved and examined. RESULTS: Four hundred and forty of a total 1976 patients (22%) were seen exclusively by triage nurses; eight (2.5%) of these 440 patients returned unplanned to the eye department. In all cases it was considered that the return of the patient would not have been preventable by initial attention of the ophthalmologist on duty.DISCUSSION: With appropriate threshold for referral, nurses trained in slit lamp examination can offer a successful service to safely diagnose and treat common eye casualty presentations.  相似文献   
20.
The simultaneous adsorption of metal ions on bare and functionalized zero-valent iron nanoparticles (nZVI) from aqueous solution was tested using inductively coupled plasma optical emission spectrometry (ICP-OES). The nanomaterials were synthetized using borohydride reduction of iron salt followed by addition of EDTA and pyridine-2,6-dicarboxylic acid (dipicolinic acid, PDCA) in different molar ratios. Functionalized materials were characterized by FT-IR, XRD and SEM-EDS methods. The ligand attachment on the particles was confirmed by FT-IR spectroscopy. The formation of a magnetite and feroxyhyte shell on the core of functionalized nanoparticles was confirmed by the XRD study. Transformation of chain-like structures into clusters of nanospheres with smaller diameter size was observed from SEM study of EDTA-nVZI particles. The average diameter of bare nZVI particles comprised 115 nm, while EDTA functionalization resulted in an average diameter of 22 and 35 nm. The PDCA-nZVI particles obtained with the molar ratio of Fe : PDCA = 1 : 1 retain the chain-like structure with enlargement of the average particle diameter to 267 nm. SEM study of PDCA-nZVI particles that were produced using the ratio Fe : PDCA = 2 : 1 have demonstrated the unique property of elongation into ellipsoidal forms of reduced dimensions (a = 61 nm; b = 28 nm). The simultaneous metal ion removal from aqueous solution was the most efficient in the case of bare nZVI particles (91–97%). EDTA functionalization was found to be highly selective for Cu and Cr removal (95%), while PDCA functionalization shows selective adsorption of Cu, Cr and V in an aqueous medium (93%). Iron nanoparticles functionalized with PDCA in both of the used ratios showed more efficient metal ion adsorption in the case when smaller ellipsoidal particles were formed.

Surface modification of nZVI particles by EDTA and PDCA leads to the formation of magnetite and feroxyhyte shell. PDCA capping caused the elongation of spheres into ellipsoids. Metals adsorption was more efficient on smaller ellipsoidal particles.  相似文献   
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