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81.
We present 2 resected cases of thymic tuberculosis, which had been preoperatively diagnosed as invasive thymoma, using a thallium-201 ((201)Tl) single photon emission computed tomography ((201)Tl SPECT). [Patient 1] A 74-old-male with a 32-year history of steroid therapy for rheumatic arthritis was diagnosed with an anterior mediastinal tumor by routine chest CT scans after onset of myocardial infarction. [Patient 2] A 56-old-female with a 28-year history of diabetes mellitus presented with a dry cough. A chest CT demonstrated an anterior mediastinal tumor. Neither patient showed pulmonary infiltrations on chest x-ray. (201)Tl SPECT was undertaken for each patient. Abnormal findings could not be detected on a planar image of the scintigraphy; however, on SPECT images accumulations of (201)Tl were clearly detected in the anterior mediastinal mass and a thymoma was thus suspected in each case. Total thymectomy was carried out in each case and the mass then diagnosed as caseous granuloma in the thymus. Both patients are well without recurrence after operation. In patients with a (201)Tl SPECT positive anterior mediastinal tumor associated with an immunologically deficient status, and with negative findings in planar images on thallium scintigraphy, the possibility of thymic tuberculosis should be considered.  相似文献   
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The self-assembly of polyvinyl alcohol (PVA) and benzene-1,4-diboronic acid (DBA) is employed as a sol–gel method for one-step fabrication of hydrogel coatings with versatile functionalities. A mixture of PVA and DBA in aqueous ethanol is prepared as a coating agent. The long pot life of the mixture allows for the coating of a wide range of materials with hydrogel films by simple cast- and dip-coating techniques. The resultant films show negligible dissolution in water and the intrinsic hydrophilicity of PVA provides the films with functional properties, such as improved antifogging property and resistance to protein and cell fouling. The self-assembling process shows adaptive inclusion properties toward nanoscale materials, such as metal–organic coordination polymers and inorganic nanoparticles, affording composite films. Furthermore, the coating film exhibits a unique secondary functionalization reactivity toward boronic acid-appended fluorescent dyes, through which a variety of materials are converted into fluorescent materials.

The self-assembly of polyvinyl alcohol (PVA) and benzene-1,4-diboronic acid (DBA) is employed as a sol–gel method for one-step fabrication of hydrogel coatings with versatile functionalities.  相似文献   
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We examined a novel human feeder cell layer of mesenchymal stem cells harvested from human adipose tissues. Gene expression analyses and colony-forming assay with human primary epithelial cells showed that the adipose tissue-derived mesenchymal stem cells produced various factors to support epithelial stem/progenitor maintenance and cell growth. Using the mesenchymal stem cells as novel feeder layers, transplantable epithelial cell sheets could be effectively generated ex vivo on temperature-responsive cell-culture surfaces.  相似文献   
87.
Desmoid tumor, also referred to as aggressive fibromatosis, is a relatively rare, locally infiltrative, histologically benign tumor. This report details a case of desmoid tumor presented as a superior sulcus tumor, which showed a unique manifestation in the vertebral bodies on computed tomography.  相似文献   
88.
We report a case of groove pancreatitis (GP) associated with a true pancreatic cyst. An 81-year-old man who had suffered epigastric pain for 4 months was referred to Saisekai Kure Hospital. Computed tomography and endoscopic retrograde pancreatography showed a cystic lesion in the groove area of the pancreas. Serum amylase elevation and imaging findings suggested GP due to the cyst. Six weeks of medical treatment did not improve the clinical symptoms. Therefore, pancreatoduodenectomy was performed. Histologic examination revealed a true cyst with intraluminal necrosis, which produced a protein plug that obstructed the Santorini duct. The parenchyma surrounding the groove area showed marked fibrosis and inflammatory cell infiltration. GP due to true pancreatic cyst was diagnosed. Although GP is usually caused by overconsumption of alcohol, which leads to changes in the pancreatic juice and the ultimate blockage of pancreatic outflow, the histologic features in our patient suggest that true pancreatic cyst stands as a secondary cause of GP.  相似文献   
89.
From October 2006 to December 2007, wild specimens of the pufferfish Takifugu poecilonotus (93 females, 45 males) were collected from the Ariake Sea. Tissue toxicity was examined by mouse bioassay, and tetrodotoxin (TTX) content in the blood plasma by enzyme-linked immunosorbent assay. The relationship between toxicity and maturation was investigated based on changes in the gonadosomatic index: December-March in females and November-March in males, the ‘maturation period’; April, ‘just after spawning’; and the other months, the ‘ordinary period’. Toxicity of both sexes was high throughout the year, but sharply declined in April. In all tissues examined (skin, liver, and ovary) other than testis, toxicity exceeded 1000 MU/g or 10,000 MU/individual in many individuals. Seasonal profiles of tissue toxicity differed markedly between sexes. In females, liver toxicity was high during the ordinary period, and ovary toxicity was high during the maturation period. In males, little maturation-associated change in the toxin distribution was observed. Plasma TTX levels were similar between the sexes (1.59–15.1 MU/ml), and fluctuated largely throughout the year without corresponding changes in tissue toxicity. The percentage of TTX binding to high molecular-weight substances in the plasma varied in association with maturation; the binding ratio fluctuated at relatively low levels during the ordinary period, and stabilized at a high level during the maturation period.  相似文献   
90.
Although the tumor microenvironment plays a critical role in tumor progression and metastasis, the relationship between chemotherapy resistance and modulation of the tumor microenvironment remains unclear. Here, we report a novel mechanism showing how constitutive DNA damage signals in therapy-resistant tumor cells suppress antitumor immunity in an integrin-αvβ3-dependent manner. Integrin-αvβ3 was upregulated on various therapy-resistant tumor cells through chronic activation of ATM/Chk2-and NFκB-mediated pathways. Inhibiting tumor-specific expression of integrin-αvβ3 improved therapeutic responses to anticancer drugs by stimulating endogenous host immune systems. Mechanistic investigations revealed that tumor-specific integrin-αvβ3 expression targeted dendritic cells, facilitating their ability to phagocytose viable therapy-resistant tumor cells and thereby impaired their ability to cross-prime antigen-specific T lymphocytes. Together, our results clarify the detrimental effects of constitutive DNA damage signals to chemosensitivity and antitumor immunity. Furthermore, these findings suggest that integrin-αvβ3 targeting may benefit patients' refractory to current anticancer regimens by defeating DNA damage signaling-induced immune escape.  相似文献   
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