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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
2.
Kambiz Dowlatshahi M. D. Ming Fan M. D. Mahsa Shekarloo B. A. Kenneth J. Bloom M. D. Victor E. Gould M. D. 《The breast journal》1996,2(5):304-311
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
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.
4.
Worldwide genomic diversity of the human papillomaviruses-53, 56, and 66, a group of high-risk HPVs unrelated to HPV-16 and HPV-18 总被引:3,自引:0,他引:3
Prado JC Calleja-Macias IE Bernard HU Kalantari M Macay SA Allan B Williamson AL Chung LP Collins RJ Zuna RE Dunn ST Ortiz-Lopez R Barrera-Saldaña HA Cubie HA Cuschieri K von Knebel-Doeberitz M Sanchez GI Bosch FX Villa LL 《Virology》2005,340(1):95-104
Among more than 200 human papillomavirus (HPV) types presumed to exist, 18 "high-risk" HPV types are frequently found in anogenital cancer. The best studied types are HPV-16 and 18, which are only distantly related to one another and form two separate phylogenetic branches, each including six closely related types. HPV-30, 53, 56, and 66 form a third phylogenetic branch unrelated to HPV-16 and 18. Worldwide comparison of HPV-16 and 18 isolates revealed a distribution of variant genomes that correlated with the geographic origin and the ethnicity of the infected cohort and led to the concept of unique African, European, Asian, and Native American HPV-16 and 18 variants. Here, we address the question whether similar phylogenies are found for HPV-53, 56, and 66 by determining the sequence of the long control regions (LCR) of these HPVs in samples from Europe, Asia, and Africa, and from immigrant societies in North and South America. Phylogenetic trees calculated from point mutations and a few insertions/deletions affecting 2-4.2% of the nucleotide sequences were distinct for each of the three HPVs and divergent from HPV-16 and 18. In contrast to the "star-phylogenies" formed by HPV-16 and 18 variants, 44 HPV-53 isolates represented nine variants, which formed two deep dichotomic branches reminiscent of the beginning split into two new taxa, as recently observed for subtypes of HPV-44 and 68. A total of 66 HPV-56 isolates represented 17 variants, which formed three branches preferentially containing European, Asian, and African variants. Variants of a fourth branch, deeply separated from the other three, were characterized by a 25 bp insertion and created a dichotomy rather than star-like phylogeny. As it contained isolates from cohorts in all continents, it may have evolved before the spread of humans into all continents. 18 of 31 HPV-66 isolates represented the prototype clone, which was found in all parts of the world, while the remaining 13 clones formed 11 branches without any geographic association. Our findings confirm the notion of a quantitatively limited genomic diversity of each HPV type with some correlation to the geographic origin of the sample. In addition, we observed in some variants of these three HPV types mutations that affect the amino acid sequence of the E6 oncoproteins and the L1 capsid protein, supporting the possibility of immunogenic and oncogenic diversity between variants of any HPV type. 相似文献
5.
Effect of Chlamydia pneumoniae on cellular ATP content in mouse macrophages: role of Toll-like receptor 2 下载免费PDF全文
Yaraei K Campbell LA Zhu X Liles WC Kuo CC Rosenfeld ME 《Infection and immunity》2005,73(7):4323-4326
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
6.
Use of multiple PCR primer sets for optimal detection of human papillomavirus. 总被引:10,自引:7,他引:10 下载免费PDF全文
F Karlsen M Kalantari A Jenkins E Pettersen G Kristensen R Holm B Johansson B Hagmar 《Journal of clinical microbiology》1996,34(9):2095-2100
Using multiple PCR primer sets, we tried to optimize the detection of human papillomavirus (HPV) in DNA samples isolated from 361 frozen biopsy specimens from patients with invasive cervical carcinomas. The HPVs detected were placed into three distinct groups, including group I/Inex at Telelab (Skien, Norway) and group Ineg and group II at the Norwegian Radium Hospital (Oslo, Norway). The consensus primer sets were Oli-1b-oli-2i, My09-My11, Gp5-Gp6, and Gp(5+)-Gp6+ from the HPV L1 gene and CpI-CpIIG from the E1 gene. Using these consensus primers together with the type-specific primers from E6-E7, we found that 355 patients (98%) were HPV positive. Type-specific primers for HPV types 11, 16, 18, 31, 33, and 35 detected more HPV-infected patients than the most sensitive consensus primer set, while the three consensus primer sets My, Gp/Gp+, and Cp together detected more HPV-positive patients than the type-specific primers. Testing of sensitivity of the PCR with SiHa cells serially diluted in lymphocytes (HPV-negative cells) indicated a detection limit of 6,300 HPV type 16 DNA copies with consensus primers (My, Gp+, and Cp) and 126 original HPV type 16 DNA copies with type-specific primers. Comparison of the amplification results for consensus L1 primers and type-specific E6-E7 primers indicated the presence of L1 deletions in 23 of 56 samples. The conclusion is that in PCR detection systems, multiple consensus primers and type-specific primers should be used in order to detect all patients harboring HPV. 相似文献
7.
Hossein Kalantari Rajnish Jaiswal Isaac Bruck Hussein Matari Farzaneh Ghobadi Jeremy Weedon Getaw Worku Hassen 《The American journal of emergency medicine》2013,31(11):1595-1597
BackgroundTraditionally, intracranial pressure is measured by direct ventriculostomy, which is invasive. Noninvasive measures such as bedside ultrasound and magnetic resonance imaging have been advocated and utilized recently to assess the intracranial pressure. The role of this study is to determine the degree of agreement between measurements of the optic nerve sheath diameter by computed tomography (CT) and magnetic resonance imaging (MRI).Materials and MethodsRetrospective chart review of 100 consecutive patients who had both MRI and CT scan of the head from January 1, 2011, until March 31, 2013, at our center was performed. A discrepancy of 0.2 mm between the 2 measurements was set as acceptable difference. The measurements of optic nerve sheath diameter (ONSD) were compared for agreement between the 2 modalities using the method by Bland and Altman.ResultsA total of 100 patients with both MRI and CT scan of the head were selected. Of these 100 patients, 24 were male and 76 were female. The average age was 63 years. No ONSD abnormality was detected in any of the patients. The discrepancy in measurements of the ONSD between CT and MRI in transverse plane was less than the predetermined cut-off value of 0.2 mm. Within-subject variance was estimated at 0.0058 for both CT and MRI.ConclusionComparable results without significant discrepancy as predetermined by the study groups were obtained from CT scan. Measurement of ONSD by CT scan can be used to indirectly asses the intracranial pressure in addition to clinical assessment and other signs of increased intracranial pressure on CT scan. 相似文献
8.
Getaw Worku Hassen Mohammed Al-Juboori Barbara Koppel Gokhan Akfirat Hossein Kalantari 《The American journal of emergency medicine》2018,36(4):736.e1-736.e3
Measurement of optic nerve sheath diameter (ONSD) using point of care ultrasound has been used to indirectly assess the intracranial pressure (ICP) particularly in conditions where it is raised. Direct pressure measurements using probes reaching the ventricle system correlated with ONSD using ultrasound. Attempts were made to measure the ONSD pre and post lumbar puncture (LP) after draining cerebrospinal fluid (CSF) as well as post ventricular shunt placement. We report ONSD measurement and demonstrate dynamic changes during LP in a patient with known idiopathic intracranial hypertension (IIH). 相似文献
9.
Maryam Shojaeifard MD Sedigheh Saedi MD Alireza Alizadeh Ghavidel MD Mohammad Reza Karimlu MD Mohammad Kasaei MD Hamid Reza Pouraliakbar MD Kambiz Mozaffari MD 《Echocardiography (Mount Kisco, N.Y.)》2020,37(3):462-464
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
10.