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1.
This paper describes and analyzes a proposed solution of fundamental limitative factor of teleradiology to overcome the teleradiology usages problems in underdeveloped and developing countries. The goal is to achieve a very simple and cost-efficient way to take advantage of teleradiology in anywhere even in remote and rural areas. To meet the goal of this study, the following methodology which is consists of two main procedures was done: (1) Using a digital camera in order to provide a digital image from radiographs. (2) Using an image compression tool in order to compress digital images. The results showed that there is no significant difference between digital images (non-compress and compress images) and radiographic films. Also, there was a logic relationship between the diagnostic quality and diagnostic accuracy. Since the maximum percent of diagnostic accuracy can be seen among “Good” quality images and the minimum to was related “Poor”. The results of our study indicate that a digital camera could be utilized to capture digital images from radiographic films of chest x-ray. To reduce the size of digital images, a lossy compression technique could be applied at compression percent of 50 or less without any significant differences. The compressed images can be sent easily by email to other places for consultation and also they can be stored with a smaller size.  相似文献   
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Abstract: Coagulation leading to fibrosis of mammo-graphically detected breast cancers by interstitial laser therapy was tested as an alternative to surgical removal. Availability of computerized stereotaxic digital imaging allows the precise placement of laser and thermal needles into the target tumor and its controlled ablation by heat. The methodology of interstitial laser therapy (ILT), evolution of the subsequently removed tumors, and their histologic appearance are outlined.
Eight patients with mammographically well-defined tumors were selected. Definitive diagnosis and receptor evaluation were made on core biopsies. Under local anesthesia, stereotaxically guided diode laser energy at 5–10 w was delivered via a 400 xm fiber in a 19-gauge needle placed into the center of the tumor until the peripheral temperature exceeded 60°C. Patients experienced transient pain and pyrexia. Subsequent to ILT, seven invasive carcinomas were excised while one case of multiple papillomas was kept under surveillance. Histologic study revealed central necrosis but some peripheral residual tumor in the first five cases. In the last two, central necrosis surrounded by concentrically arranged, recognizable but severely injured, focally "windswept" and "ghostlike" tumor and granulation tissue were noted. The multiple papillomas showed radiologic shrinkage at 5 months and extensive fibrosis on needle biopsy.
ILT is an attractive new method of treating small, well-defined breast tumors and offers a potentially significant alternative to surgical removal; further exploration is warranted.  相似文献   
3.
Chlamydiae are obligate intracellular gram-negative bacteria and are dependent on the host cell for ATP. Thus, chlamydial infection may alter the intracellular levels of ATP and affect all energy-dependent processes within the cell. We have shown that both live C. pneumoniae and inactivated C. pneumoniae induce markers of cell death prior to completion of the bacterial growth cycle. As depletion of ATP could account for the observed increase in cell death, the effects of C. pneumoniae on ATP concentrations within mouse macrophages were investigated. Live, heat-killed, and UV-inactivated C. pneumoniae cultures (at multiplicities of infection [MOIs] of 0.01, 0.1, and 1.0) were incubated with mouse bone marrow macrophages isolated from C57BL/6J mice and mice deficient in Toll-like receptors. Treatment of the macrophages with both live and inactivated C. pneumoniae increased the ATP content of the cells. In cells infected with live C. pneumoniae, the increase was inversely proportional to the MOI. In cells treated with inactivated C. pneumoniae, the increase in ATP content was smaller than that induced by infection with live organisms and was proportional to the MOI. The increase in ATP content early in the developmental cycle was independent of the growth of C. pneumoniae, while sustained induction required live organisms. The capacity of C. pneumoniae to increase the ATP content was ablated in macrophages deficient in expression of either Toll-like receptor 2 or the Toll-like receptor accessory protein MyD88. In contrast, no effect was observed in macrophages lacking expression of Toll-like receptor 4.  相似文献   
4.
Primary tumors of the heart are rare with a reported incidence of about 0.002% to 0.3% at autopsy. A cardiac hemangioma is a form of benign primary cardiac tumor that often presents with atypical clinical symptoms. Hemangiomas are generally isolated lesions. Here, we report a patient with previous hepatic hemangioma who later was found to have a large coexistent cardiac hemangioma presenting with cardiac compressive symptoms.  相似文献   
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We showed previously that prior exposure to a modified ultrasound regimen prevents kidney ischemia-reperfusion injury (IRI) likely via the splenic cholinergic anti-inflammatory pathway (CAP) and α7 nicotinic acetylcholine receptors (α7nAChR). However, it is unclear how ultrasound stimulates the splenic CAP. Further investigating the role of the spleen in ischemic injury, we found that prior splenectomy (–7d) or chemical sympathectomy of the spleen with 6-hydroxydopamine (6OHDA; –14d) exacerbated injury after subthreshold (24-minute ischemia) IRI. 6-OHDA–induced splenic denervation also prevented ultrasound-induced protection of kidneys from moderate (26-minute ischemia) IRI. Ultrasound-induced protection required hematopoietic but not parenchymal α7nAChRs, as shown by experiments in bone marrow chimeras generated with wild-type and α7nAChR–/– mice. Ultrasound protection was associated with reduced expression of circulating and kidney-derived cytokines. However, splenocytes isolated from mice 24 hours after ultrasound treatment released more IL-6 ex vivo in response to LPS than splenocytes from sham mice. Adoptive transfer of splenocytes from ultrasound-treated (but not sham) mice to naïve mice was sufficient to protect kidneys of recipient mice from IRI. Ultrasound treatment 24 hours before cecal ligation puncture–induced sepsis was effective in reducing plasma creatinine in this model of AKI. Thus, splenocytes of ultrasound-treated mice are capable of modulating IRI in vivo, supporting our ongoing hypothesis that a modified ultrasound regimen has therapeutic potential for AKI and other inflammatory conditions.  相似文献   
8.

Background

Nighttime blood pressure (BP) and systolic BP variability on ambulatory blood pressure monitoring (ABPM) have been strongly associated with target-organ damage in hypertensive adults. The clinical relevance of these variables in children with hypertension remains under-studied.

Methods

The study group included children aged 5–18 years old referred to the outpatient nephrology clinic for an elevated casual BP who underwent an ABPM and echocardiography (ECHO) study and did not have secondary hypertension. The interpretation of ABPM parameters and left ventricular mass index (LVMI) was based on normative references.

Results

Seventy-two children fulfilled the inclusion criteria. The association of various potential predictors including age, BMI z-score, casual BP z-score and ABPM parameters (BP z-score, BP load, nocturnal dipping and BP variability- within-subject standard deviation (SD) of BP) with LVMI was analyzed. On adjusted regression analysis, nighttime systolic BP load [standardized regression coefficient (β) 0.23; p?<?0.05] and daytime systolic BP variability (β 0.37; p?<?0.05) had significant association with LVMI.

Conclusions

In children with primary hypertension, nighttime systolic BP load and daytime systolic BP variability had a stronger association with LVMI than casual BP and other ABPM parameters. Future longitudinal studies are needed to establish the causality among these variables.  相似文献   
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目的 研究肝动脉化疗栓塞治疗后肝脏肿瘤内碘油沉积对碳离子放疗剂量的影响。方法 对比纯碘油、纯凝胶和碘油凝胶混合物实际相对水阻止本领(RLSP)和其CT图像转化获得的RLSP。在7例典型有碘油沉积病例的CT图像上制定碳离子放疗计划,然后基于前述分析结果,将碘油沉积区域RLSP修正为正常肝组织,将先前制定碳离子放疗计划在修正后CT图像上重新计算,比较在不同CT图像上等效水深度和剂量分布的差异。结果 依据CT图像HU值,碘油和碘油凝胶混合物转化的RLSP比实际测量值增加4.6%~139.0%。7例临床病例中,原始图像上碘油沉积可致射野路径上的等效水深度平均增加(0.89±0.41)cm,可使靶区远端1 cm区域内平均剂量升高(3.83±1.71)Gy (相对生物剂量)。结论 在肝动脉化疗栓塞治疗后有碘油沉积的CT图像上制定碳离子治疗计划时需将碘油沉积部位的HU值或RLSP修正为正常肝组织。  相似文献   
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