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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   
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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   
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In this double-blind, randomised trial conducted in 22 centres in the USA, azithromycin given over five days, as a once-a-day regimen, (500 mg on day 1, 250 mg on days 2–5) was compared with cephalexin (500 mg b.i.d.) given for ten days in the treatment of patients with skin and skin structure infections. A total of 366 patients entered the study and 179 of these were eligible for the efficacy analysis. The overall clinical response to azithromycin was 94.0 %, compared with 95.8 % for cephalexin. The clinical cure rates were 53.0 % for azithromycin and 59.4 % for cephalexin; the respective improvement rates were 41.0 % and 36.5 %. Distribution of response (cured, improved, failed) was similar in each group (p=0.37). The bacteriological eradication rate for azithromycin-treated patients was 94.2 % and for cephalexin-treated patients was 90.3 % (p=0.34). Clinical and bacteriological response was similar in each group for all primary diagnoses. The two antibiotics were well tolerated, the overall incidence of side effects being 13.7 % with approximately 60 % due to gastrointestinal disturbances. In all but one case (cephalexin) the severity of the reported side effects was mild or moderate. Six patients withdrew from the study due to treatment-related events; five had been treated with azithromycin and one with cephalexin. In summary, a five-day, once-daily regimen of azithromycin was as effective as a ten-day, twice-daily regimen of cephalexin in the treatment of patients with skin and skin structure infections.  相似文献   
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Manipulating immune responses with immunosuppressive agents that target NFAT   总被引:11,自引:0,他引:11  
Kiani A  Rao A  Aramburu J 《Immunity》2000,12(4):359-372
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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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