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81.
Intracellular structures of HeLa cells are observed using a direct electron beam excitation-assisted fluorescence (D-EXA) microscope. In this microscope, a silicon nitride membrane is used as a culture plate, which typically has a low biocompatibility between the sample and the silicon nitride surface to prevent the HeLa cells from adhering strongly to the surface. In this work, the surface of silicon nitride is modified to allow strong cell attachment, which enables high-resolution observation of intracellular structures and an increased signal-to-noise ratio. In addition, the penetration depth of the electron beam is evaluated using Monte Carlo simulations. We can conclude from the results of the observations and simulations that the surface modification technique is promising for the observation of intracellular structures using the D-EXA microscope.OCIS codes: (170.0170) Medical optics and biotechnology, (170.0180) Microscopy  相似文献   
82.
We report a case of a very rare disorder, histiocytic sarcoma, from a review of our autopsy cases. The neoplastic cells that proliferated in organs throughout the body were large cells containing eosinophilic cytoplasm and pleomorphic nuclei with prominent nucleoli. In the bone marrow, erythrophagocytosis by neoplastic cells was observed. The neoplastic cells were positive not only for lysozymes and CD68 (KP-1, PG-M1, and Ki-M1P) but also for a monocyte/macrophage-specific marker, CD163. In contrast, the results of tests for markers of myeloid cells, lymphoid cells, and epithelial cells were all negative. In a polymerase chain reaction study of paraffin-embedded tissues, analyses for the rearrangement of immunoglobulin heavy chain and T-cell receptor-γ genes were negative. The current World Health Organization diagnostic criteria for histiocytic sarcoma regard immunohistochemical investigation as crucial. In this regard, the highly specific positivity for CD163 in this patient indicates that immunohistochemical staining of CD163 is very useful for the diagnosis of histiocytic sarcoma.  相似文献   
83.
Isolated ACTH deficiency with Graves' disease: a case report   总被引:1,自引:0,他引:1  
A 60-year-old man was hospitalized with complaints of general malaise and weight loss. On admission, ACTH and cortisol levels were low, and thyroid function tests revealed hyperthyroidism. These findings and further examination led to a diagnosis of isolated ACTH deficiency (IAD) with Graves' disease. It is known that IAD is frequently associated with thyroid disease, but its association with Graves' disease is rare. The present case is worth noting, because some reports indicate that aggravation of associated Graves' disease may concomitantly aggravate adrenal insufficiency in patients with IAD.  相似文献   
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BACKGROUND Although several techniques for endoscopic ultrasound-guided biliary drainage(EUS-BD)are available at present,an optimal treatment algorithm of EUS-BD has not yet been established.AIM To evaluate the clinical utility of treatment method conversion during single endoscopic sessions for difficult cases in initially planned EUS-BD.METHODS This was a single-center retrospective analysis using a prospectively accumulated database.Patients with biliary obstruction undergoing EUS-BD between May 2008 and April 2016 were included.The primary outcome was to evaluate the improvement in EUS-BD success rates by converting the treatment methods during a single endoscopic session.Secondary outcomes were clarification of the factors leading to the conversion from the initial EUS-BD and the assessment of efficacy and safety of the conversion as judged by technical success,clinical success,and adverse events(AEs).RESULTS A total of 208 patients underwent EUS-BD during the study period.For 18.8%(39/208)of the patients,the treatment methods were converted to another EUSBD technique from the initial plan.Biliary obstruction was caused by pancreatobiliary malignancies,other malignant lesions,biliary stones,and other benign lesions in 22,11,4,and 2 patients,respectively.The reasons for the difficulty with the initial EUS-BD were classified into the following 3 procedures:Target puncture(n=13),guidewire manipulation(n=18),and puncture tract dilation(n=8).Technical success was achieved in 97.4%(38/39)of the cases and clinical success was achieved in 89.5%of patients(34/38).AEs occurred in 10.3%of patients,including bile leakage(n=2),bleeding(n=1),and cholecystitis(n=1).The puncture target and drainage technique were altered in subsequent EUSBD procedures in 25 and 14 patients,respectively.The final technical success rate with 95%CI for all 208 cases was 97.1%(95%CI:93.8%-98.9%),while that of the initially planned EUS-BD was 78.8%(95%CI:72.6%-84.2%).CONCLUSION Among multi-step procedures in EUS-BD,guidewire manipulation appeared to be the most technically challenging.When initially planned EUS-BD is technically difficult,treatment method conversion in a single endoscopic session may result in successful EUS-BD without leading to severe AEs.  相似文献   
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Oral Diseases (2012) 18, 756-762 Objectives: An odontoma, which shows proliferating odontogenic epithelium and mesenchymal tissue, is one of the most common odontogenic tumors encountered. These are commonly found in tooth-bearing regions, although the etiology remains unknown. There are no previous reports of an established line of immortalized human odontoma cells. Methods: Using odontoma fragments obtained from a girl treated at our department, we established an immortalized human odontoma cell line and investigated cell morphology, dynamic proliferation, the presence of contamination, and karyotype. Moreover, cell characterization was examined using osteogenic and odontogenic markers. Results: We successfully established a mesenchymal odontoma cell (mOd cells). The cells were found to be fibroblastic and had a high level of telomerase activity. Cell growth was confirmed after more than 200 population doublings without significant growth retardation. mOd cells expressed mRNA for differentiation markers, including collagen type I (COLI), alkaline phosphatase, bone sialoprotein, osteopontin, osteocalcin, cementum-derived protein (CP-23), dentin sialophosphoprotein (DSPP), and distal-less homeobox 3 (DLX3), as well as bone morphogenetic proteins (BMPs). In addition, they showed a high level of calcified nodule formation activity in vitro. Conclusions: We successfully established a cell line that may be useful for investigating the mechanisms of normal odontogenesis as well as characteristics of odontoma tumors.  相似文献   
88.
The IDSA guideline for management of febrile neutropenic patients updated in 2010 recommends monotherapy with anti-pseudomonal-lactam agents, including piperacillin-tazobactam (PIPC/TAZ) for high-risk patients. However, clinical studies of PIPC/TAZ are limited in Japanese patients. In this study, we conducted an open-labeled non-randomized prospective trial to examine the efficacy and safety of PIPC/TAZ as an empirical treatment for Japanese patients with febrile neutropenia. Forty-nine febrile episodes in neutropenic patients excluding those undergoing allogeneic stem cell transplantation (high risk 36, low risk 13) were analyzed. The overall response rate was 71%, and no significant differences between the high-risk and the low-risk group were observed (high risk 72%, low risk 69%). Neither PS nor usage of G-CSF affected the response rate. No major side effects were observed in the study. The efficacy and the safety profile of PIPC/TAZ treatment were comparable to those in other previous Western studies. In conclusion, this study suggests PIPC/TAZ is effective and well tolerated as an initial empirical treatment for febrile neutropenic Japanese patients.  相似文献   
89.
Computed tomography colonography (CTC) was performed in 5 patients with pneumatosis cystoides intestinalis (PCI). The virtual colonoscopy view of CTC as well as total colonoscopy (TCS) findings showed polypoid lesions in the colon, and multiplanar reconstruction images of the colon revealed in the polypoid lesions of the colon. We confirmed the diagnosis of PCI in all cases. CTC also detected the PCI lesions in the subserosa of the colonic wall which were not detected by TCS. Accurate evaluation of the extent of PCI involvement was obtained by CT air-contrast enema images. CTC is useful for detection of PCI lesions, assessment of the exact site and final diagnosis for PCI.  相似文献   
90.
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