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81.
The term ‘emphysema’ is generally used in a morphological sense, and therefore imaging modalities have an important role in diagnosing this disease. In particular, high resolution computed tomography (HRCT) is a reliable tool for demonstrating the pathology of emphysema, even in subtle changes within secondary pulmonary lobules. Generally, pulmonary emphysema is classified into three types related to the lobular anatomy: centrilobular emphysema, panlobular emphysema, and paraseptal emphysema. In this pictorial review, we discuss the radiological – pathological correlation in each type of pulmonary emphysema. HRCT of early centrilobular emphysema shows an evenly distributed centrilobular tiny areas of low attenuation with ill-defined borders. With enlargement of the dilated airspace, the surrounding lung parenchyma is compressed, which enables observation of a clear border between the emphysematous area and the normal lung. Because the disease progresses from the centrilobular portion, normal lung parenchyma in the perilobular portion tends to be preserved, even in a case of far-advanced pulmonary emphysema. In panlobular emphysema, HRCT shows either panlobular low attenuation or ill-defined diffuse low attenuation of the lung. Paraseptal emphysema is characterized by subpleural well-defined cystic spaces. Recent topics related to imaging of pulmonary emphysema will also be discussed, including morphometry of the airway in cases of chronic obstructive pulmonary disease, combined pulmonary fibrosis and pulmonary emphysema, and bronchogenic carcinoma associated with bullous lung disease.  相似文献   
82.
BACKGROUND: Ulcerative colitis (UC) is a chronic inflammatory bowel disease associated with recurring inflammation of the colorectal mucosa. Recently, cytapheresis has emerged as a new treatment for patients with UC. Removal methods are mainly performed with beads [granulocyte and monocyte/macrophage adsorptive apheresis (GMCAP)] or filters [leukocytapheresis (LCAP)]. Both treatments have been reported to be effective for active UC. There have been few trials, however, comparing the efficacy of GMCAP and LCAP. In this study, we prospectively evaluated the efficacy of LCAP and GMCAP for the treatment of active UC. METHODS: Thirty-nine patients [18 male, 21 female; mean age 38.7 years; duration of disease 6 years; clinical activity index (CAI) >6 points] with moderate-to-severe active UC were randomly assigned to the LCAP (n=21) or GMCAP group (n=17). Adacolumn (cellulose acetate beads; Japan Immunoresearch Laboratories, Takasaki, Japan) for GMCAP and Cellsorba EX (polyethylene phthalate fibers; Asahi Medical Co. Ltd, Tokyo, Japan) for LCAP were used for leukocyte removal. Patients received two sessions of cytapheresis in the first week, followed by four weekly administrations. Steroid doses were tapered if patients achieved clinical improvement. When the CAI score had decreased by 5 points or more, the patient was considered to have improved. RESULTS: Thirteen patients in the GMCAP group and 14 in the LCAP group achieved clinical improvement. No significant difference was found in clinical response and clinical course between LCAP and GMCAP. Hemoglobin levels were significantly decreased immediately after one session of cytapheresis in the LCAP group. No severe adverse effects were observed in any of the patients. No significant differences were observed in any clinical parameters predictive of a response to either LCAP or GMCAP. But in all patients receiving cytapheresis, a high CAI score was a significant risk factor for treatment failure. All of the cytapheresis nonresponders had CAI scores >or=16. CONCLUSION: Both GMCAP and LCAP were effective treatments for active UC. Patients with severe UC and a high CAI score were, however, refractory to treatment.  相似文献   
83.
AimTo elucidate the morphological characteristics of spike-wave complexes (SWCs) causing myoclonic seizures (MS) in childhood-onset idiopathic myoclonic epilepsies.Subjects and MethodsThe subjects were 8 patients, including 4 with epilepsy with myoclonic-atonic seizures (EMAS), 3 with myoclonic epilepsy in infancy (MEI) and 1 with idiopathic unclassifiable myoclonic epilepsy. Morphometric parameters of the SWCs were compared between those with MS [SWC-MS (+)] and those without MS [SWC-MS (-)], and a correlation coefficient analysis was performed between the SWC parameters and the duration of myoclonic electromyogram (EMG) potentials.ResultsA total of 155 SWC-MS (+) (range: 7 ~ 34) and 80 SWC-MS (-) (10 each as a control) were analyzed. Comparison of the parameters of the SWCs between SWC-MS (+) and SWC-MS (-) demonstrated that the depth and the width of the positive-sharp-components (PSC) in the SWC-MS (+) were significantly deeper in amplitude and longer in duration than those in the SWC-MS (-), respectively, in all 8 patients (P < 0.05), whereas the number of the polyphasic-multiple-spike-components (PMSC) and the height of negative-spike-components (NSC) were not significantly different in most of the patients, respectively. The depth and the width of PSC were also significantly correlated with the duration of myoclonic EMG potentials in all patients except one [depth of PSC (n = 7): r = 0.623 ~ 0.888; width of PSC (n = 8): r = 0.676 ~ 0.948, P < 0.05].ConclusionsThis study revealed that the depth and width of PSC of the SWC are positively correlated with the MS intensity in childhood-onset idiopathic myoclonic epilepsies and are an important neurophysiological marker to generate MS.  相似文献   
84.
Analyzing the evolutionary pattern of the influenza A(H1N1)pdm09 strain in different regions is important for understanding its diversification. We therefore conducted this study to elucidate the genetic variability and molecular evolution of the influenza A(H1N1)pdm09 strains that circulated during the 2009–2010 and 2010–2011 influenza seasons in Sendai, Japan. Nasopharyngeal swab specimens were collected from patients with influenza-like illnesses who visited outpatient clinics in Sendai City, Japan, from September 2009 to April 2011. A total of 75 isolates were selected from September 2009 to April 2011 to analyze the genetic changes in the entire hemagglutinin 1 (HA1) segment of the HA gene and the neuraminidase (NA) gene based on sequence analysis. Bayesian coalescent Markov chain Monte Carlo analyses of HA1 and NA gene sequences were performed for further analysis. High sequence identities were observed for HA1 and NA in influenza A(H1N1)pdm09, displaying 99.06 and 99.33 % nucleotide identities, respectively, with the A(H1N1)pdm09 vaccine strain A/California/07/2009. The substitution rates of nucleotides for HA1 in the 2009–2010 and 2010–2011 were 1.5 × 10?3 and 1.6 × 10?3 substitutions per site per year, respectively. Phylogenetic tree analysis demonstrated that Sendai isolates were clustered into global clade 7, which is characterized by an S203T mutation in the HA1 gene. Moreover, two distinct circulation clusters were present in the 2010–2011 season. Mutations were present in antigenic or receptor-binding domains of the HA1 segment, including A141V, S143G, S183P, S185T, and S203T. The Bayesian skyline plot model illustrated a steady rate for the maintenance of genetic diversity, followed by a slight increase in the later part of the 2010–2011 season. Selection analysis revealed that the HA1 (position 197) and NA (position 46) sites were under positive selection; however, no known mutation conferring resistance to NA inhibitors such as H275Y was observed. The effect on control of the influenza A(H1N1)pdm09 virus, including vaccine strain selection, requires continuous monitoring of the strain by genetic surveillance.  相似文献   
85.
ObjectiveTo review the virology, immunology, epidemiology, clinical manifestations, and treatment of the following 3 major zoonotic coronavirus epidemics: severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and coronavirus disease 2019 (COVID-19).Data SourcesPublished literature obtained through PubMed database searches and reports from national and international public health agencies.Study SelectionsStudies relevant to the basic science, epidemiology, clinical characteristics, and treatment of SARS, MERS, and COVID-19, with a focus on patients with asthma, allergy, and primary immunodeficiency.ResultsAlthough SARS and MERS each caused less than a thousand deaths, COVID-19 has caused a worldwide pandemic with nearly 1 million deaths. Diagnosing COVID-19 relies on nucleic acid amplification tests, and infection has broad clinical manifestations that can affect almost every organ system. Asthma and atopy do not seem to predispose patients to COVID-19 infection, but their effects on COVID-19 clinical outcomes remain mixed and inconclusive. It is recommended that effective therapies, including inhaled corticosteroids and biologic therapy, be continued to maintain disease control. There are no reports of COVID-19 among patients with primary innate and T-cell deficiencies. The presentation of COVID-19 among patients with primary antibody deficiencies is variable, with some experiencing mild clinical courses, whereas others experiencing a fatal disease. The landscape of treatment for COVID-19 is rapidly evolving, with both antivirals and immunomodulators demonstrating efficacy.ConclusionFurther data are needed to better understand the role of asthma, allergy, and primary immunodeficiency on COVID-19 infection and outcomes.  相似文献   
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87.
[Purpose] This study explored the roles of physical therapists (PTs) in introducing assistive products, which are essential for living securely and stably at home, and examined how PTs can fulfill these roles more efficiently and effectively. [Subjects and Methods] A questionnaire on introducing assistive products was administered to PTs working at randomly selected hospitals, health-care facilities for the elderly requiring long-term care, home-visit nursing stations, and other such facilities and to PTs providing physical therapy directly to the home-bound elderly disabled. The subjects of the study were 77 PTs who returned valid responses. [Results] For awareness of systems for assistive product’s introduction, PTs were more aware of the system based on the Long-Term Care (LTC) Insurance Act than the system based on the Act on Welfare for the Home-Bound Elderly Disabled. For PTs handling assistive product’s introduction for the home-bound elderly disabled, approximately 91% of the respondents answered that they had handled some cases of assistive product’s introduction, and PTs with longer clinical experience had handled more assistive product’s introduction cases. [Conclusion] The results demonstrated that PTs understand the work involved in introducing assistive products work well and that they handle it. The results, however, also suggested that educational and operational improvements are urgently required for PTs introducing assistive products essential for the lives of the home-bound elderly disabled.Key words: Assistive products, Physical therapists, Home-bound elderly disabled  相似文献   
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90.
A 73-year-old Japanese woman was referred for examination of right flank pain and progressive hypertension. Abdominal CT incidentally detected a right adrenal mass 8 cm in size. The tumor exhibited isodensity by CT and contained high-intense lesion by T2-weighted MRI. Scintigraphy with (131) I-metaiodobenzylguanidine and (131) I-adosterol showed no abnormal uptake by whole body scan. Positron emission tomography scan with (18) F-2-fluoro-D-deoxyglucose demonstrated an exclusive uptake in the right adrenal mass. Adrenocortical hormone levels and catecholamine secretion were within normal range; however, the level of serum neuron-specific enolase (NSE) was found to be markedly high. After controlling systemic blood pressure with an alpha1-blocker, the right adrenal tumor was surgically removed, along with the right kidney and inferior vena cava which adhered to it. The tumor was pathologically proven to be leiomyosarcoma, which was immunohistochemically positive with alpha-smooth muscle actin and negative with CD57, S-100 and c-kit proteins. Notably, NSE protein was massively expressed in the resected tumor. After surgery blood pressure was controlled with regular medication and serum NSE levels have since normalized. The possibility of leiomyosarcoma should be kept in mind in adrenal incidentalomas with rapid growth and atypical radiological images. Our findings suggest that circulating NSE levels may be clinically useful for early detection of recurrence.  相似文献   
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