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991.
992.
Surgical masks are widely used for the prevention of respiratory infections. However, the risk of heat stroke during intense work or exercise in hot and humid environment is a concern. This study aimed to examine whether wearing a surgical mask increases the risk of heat stroke during mild exercise in such environment. Twelve participants conducted treadmill exercise for 30 min at 6 km/h, with 5% slope, 35°C ambient temperature, and 65% relative humidity, while wearing or not a surgical mask (mask and control trials, respectively). Rectal temperature (Trec), ear canal temperature (Tear), and mean skin temperature (mean Tskin) were assessed. Skin temperature and humidity of the perioral area of the face (Tface and RHface) were also estimated. Thermal sensation and discomfort, sensation of humidity, fatigue, and thirst were rated using the visual analogue scale. Trec, Tear, mean Tskin, and Tface increased during the exercise, without any difference between the two trials. RHface during the exercise was greater in the mask trial. Hot sensation was greater in the mask trial, but no influence on fatigue and thirst was found. These results suggest that wearing a surgical mask does not increase the risk of heat stroke during mild exercise in moist heat.  相似文献   
993.
Neoplastic programmed cell death ligand 1 (PD-L1) expression, activated by PD-L1 gene alterations, is strongly associated with classic Hodgkin lymphoma (CHL). This association enabled a diagnostic consensus for lymphocyte-depleted CHL (LD-CHL), a previously enigmatic disease. We describe two patients with LD-CHL and primary extranodal disease. One patient was a 92-year-old female (Case #1) with a large mass that involved the uterus combined with swollen lymph nodes in the pelvic cavity. The second patient was a 76-year-old female (Case #2) with human T-cell leukemia virus type 1 (HTLV-1) who initially exhibited massive bone marrow involvement without peripheral lymphadenopathies. Biopsies of these tumors from the cervix uteri and bone marrow, respectively, revealed lesions rich in Hodgkin and Reed-Sternberg (H-RS) cells and diminished populations of other cell populations. Immunohistochemistry demonstrated that these H-RS cells expressed CD30, BOB1, and fascin, but not CD15, CD20, PAX5, or OCT2. They also expressed PD-L1, which led to our preferred diagnosis of LD-CHL in both patients. Epstein-Barr virus was associated with LD-CHL in Case #1, but not in Case #2. Both patients were deemed too frail for treatment. They died of disease at 1 (Case #1) and 15 months (Case #2) after the diagnosis. These findings highlight the abnormal biological behavior of this immune-escape-related lymphoid neoplasm in patients with immunodeficiency due to immune senescence and HTLV1 infection.  相似文献   
994.
Lactobacillus gasseri OLL 2716 promotes the elimination of Helicobacter pylori and is utilized in yogurts that are specifically labeled as health foods. On the other hand, milk whey fermented by Propionibacterium freudenreichii ET-3, which increases the numbers of Bifidobacterium, is effective for intestinal disorders. We previously demonstrated that oral administration of L. gasseri and P. freudenreichii fermentation metabolites (LP-FM) improved calf intestinal microflora and reduced the incidence of diarrhea. However, the detailed immunological mechanisms responsible for these effects remain to be fully understood. In this study, we investigated whether LP-FM stimulates the innate immune response and promotes the elimination of Listeria monocytogenes in mice. The C57BL/6 female mice that were treated with LP-FM or L. gasseri fermentation metabolites alone for 4 weeks had more peripheral white blood cells than the untreated control mice. In particular, LP-FM-treated mice had higher CD4- and CD8-positive T-cell counts. The levels of reactive oxygen and nitrogen species produced by peritoneal macrophages were also higher in LP-FM-treated mice. Furthermore, LP-FM-treated mice that were infected with L. monocytogenes exhibited significant enhancement of the elimination of Listeria from the spleen and the liver in comparison with untreated control mice infected with Listeria. The activation of innate immunity by LP-FM was increased by the combination of fermentation metabolites from P. freudenreichii. These results suggest that LP-FM, which contains metabolites from L. gasseri and P. freudenreichii, stimulates the function of the innate immune system, thereby significantly promoting the elimination of L. monocytogenes in mice.  相似文献   
995.
Spontaneous intracranial hypotension (SIH) is caused by cerebrospinal fluid (CSF) leakage. Patients with SIH experience postural headaches, nausea, etc., due to CSF hypovolemia. Imaging studies and clinical examinations, such as radioisotope (RI) scintigraphy, are useful for diagnosing SIH. However, 20-30% of patients do not show typical morphology and clinical test results. We previously reported that CSF contains transferrin (Tf) isoforms: “brain-type” Tf derived from the choroid plexus and “serum-type” Tf derived from blood. We showed that both isoforms increased in the CSF of patients with SIH by Western blotting. In the present study, we demonstrate that conventional ELISA for quantifying total Tf is useful for diagnosing SIH more accurately than Western blotting. In addition, SIH with chronic subdural hematoma (CSDH) was also accurately diagnosed. Total Tf in the CSF can serve as a useful biomarker for diagnosing SIH with or without CSDH.  相似文献   
996.
997.
Allogeneic hemopoietic stem cell transplantation (allo-HSCT) is the only curative therapy for refractory hematological malignancies. However, there are many treatment-related complications, including organ disorders, graft-versus-host disease (GVHD), and infectious diseases. Furthermore, there are many unclear points regarding central nervous system (CNS) complications, and the prognosis in patients with CNS complications is extremely poor. We herein report a 49-year-old woman who developed CNS-GVHD after a second transplantation for therapy-related myelodysplastic syndrome. CNS-GVHD in this case was refractory to all treatments, including steroids, and progressed. We also present a review of the literature about the symptoms, diagnosis, and treatment of CNS-GVHD.  相似文献   
998.
Purpose  The aim of this study was to examine whether 20-cm field-of-view (FOV) targeted reconstruction (TR) on contrast-enhanced (CE) chest computed tomography (CT) might improve the diagnostic value compared with simple zooming (SZ) from whole-thorax FOV images using a 2 million (2M)-pixel liquid crystal display (LCD) monitor. Materials and methods  We prospectively evaluated 44 patients. SZ images were magnified from a FOV of 26–34 cm (mean 29.7 cm). Parameters were 512 × 512 matrix and 3 mm thickness and interval. Images were reconstructed using a soft-tissue kernel. Three radiologists evaluated contour, spiculation, notch, pleural tag, invasion, and internal characteristics of the lesions using 5-scale scores. We also performed a phantom study to evaluate the spatial resolution of images. Results  The diagnostic value of the TR images was similar to that of the SZ images, with the findings identified in 88%–100% of the cases. Artifacts from highdensity structures deteriorated the image quality in six (14%), and the SZ images were judged to be preferable in five of them. In the phantom study, there was little difference in spatial resolution between the two images. Conclusion  The SZ images from whole-thorax FOV on CE chest CT were similar in quality to TR images using a 2M-pixel LCD monitor.  相似文献   
999.
Tumors originating from the nasolacrimal duct are exceedingly rare. Only a few cases have been reported previously. In advanced cases with extended tumor, differential diagnosis from lacrimal sac tumor is difficult. A 68-year-old Japanese man with intractable dacryocystitis was examined with intranasal endoscopy, computed tomography (CT) and magnetic resonance imaging (MRI). Squamous cell carcinoma extended from a medial site in the left orbit to the lacrimal orifice. En bloc resection was performed and histopathological examination of the surgical specimen using serial section suggested that the origin of the tumor was located in the nasolacrimal duct. This is the first case in nasolacrimal duct carcinoma whose differential diagnosis of origin has been studied in detail. We showed that pathological study using serial section along the duct provides useful information for diagnosing the tumor origin in addition to that obtained from imaging studies.  相似文献   
1000.

Background

Recently, a lot of cases with microcalcifications of the breast are pointed by the images of mammography (MG), because breast screening using MG become common. Although MG is a gold standard modality for detecting microcalcifications, images of ultrasonography (US) are now feasible to detect microcalcifications with recent improvements to ultrasound diagnostic devices. In this report, we analyzed clinical significance of microcalcifications detected with US images in invasive breast carcinoma.

Methods

Eighty-eight patients with invasive breast carcinoma who underwent MG and US before surgery at the Division of Breast and Endocrine Surgery of Tottori University Hospital between January 2012 and August 2013. After reviewing US images, the association between the presence of echogenic spots that indicate microcalcifications and images of MG or pathological findings was assessed.

Results

Patients without microcalcifications on US images were significantly more likely to have the Luminal A subtype and a lower nuclear grading. Conversely, patients with microcalcifications on US images were significantly more likely to have higher level of MIB-1 index, lymphovascular invasion, comedonecrosis and lymph node metastasis. The rate of detecting microcalcifications on US images was relatively good, with 81.8% of sensitivity, 94.5% of specificity and 89.8% of diagnostic accuracy. Among the calcifications detected by MG images, detected rate of calcifications with US images was higher in necrotic type (92.6%) than secretory type (33.3%).

Conclusion

This study suggest that microcalcifications of tumors detected by US images could serve as an useful prediction to evaluate the degree of malignancy for patients with invasive breast carcinoma.  相似文献   
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