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31.
We report a case of chordoma containing a spindle cell sarcomatoid component with a gradual transition from conventional chordoma.
Immunohistochemically, many tumor cells in both conventional chordoma and sarcomatoid components were positive for cytokeratins
(AE1/AE3, CAM5.2) and epithelial membrane antigen as well as vimentin. This report provides a rare example of sarcomatoid
chordoma. Familiarity with this type of bone tumor should help to avoid confusion with dedifferentiated chordoma and other
spindle cell sarcomas or carcinomas.
Received: 25 February 2000 Revision requested: 28 March 2000 Revision received: 30 May 2000 Accepted: 28 June 2000 相似文献
32.
Tskitishvili E Komoto Y Kinugasa Y Kanagawa T Song M Mimura K Tomimatsu T Kimura T Shimoya K 《Acta obstetricia et gynecologica Scandinavica》2007,86(8):915-920
BACKGROUND: S100B protein is a unique calcium-binding protein. Its biological role within the cell populations is not completely defined. Some pathological conditions that develop during pregnancy could affect S100B concentrations in the amniotic fluid, cord blood, and maternal serum. The aim of our study was to assess the correlation between S100B protein expression in the amnion, amniotic fluid and gestational age in the third trimester of uncomplicated pregnancies. METHODS: Amnion, amniotic fluid, maternal peripheral and umbilical cord blood samples were collected from healthy women who delivered at 31-36 weeks (n=17), 37-40 weeks (n=22), and 41-42 weeks (n=21). The expression of S100B in the amnion was assessed by immunohistochemistry and real-time (RT)-PCR, and its concentrations in amniotic fluid, maternal and cord blood sera were determined by ELISA. RESULTS: The S100B protein expression in the amnion and its concentrations in amniotic fluid, maternal and cord blood sera of patients in the third trimester were not significantly different at various gestational ages. CONCLUSIONS: The S100B protein expression in the amnion and the S100B protein concentrations in amniotic fluid, maternal and cord blood do not vary significantly in the third trimester of uncomplicated pregnancies. 相似文献
33.
Akira Kunimatsu Koichiro Yasaka Hiroyuki Akai Haruto Sugawara Natsuko Kunimatsu Osamu Abe 《Magnetic resonance in medical sciences》2022,21(1):95
Texture analysis, as well as its broader category radiomics, describes a variety of techniques for image analysis that quantify the variation in surface intensity or patterns, including some that are imperceptible to the human visual system. Cerebral gliomas have been most rigorously studied in brain tumors using MR-based texture analysis (MRTA) to determine the correlation of various clinical measures with MRTA features. Promising results in cerebral gliomas have been shown in the previous MRTA studies in terms of the correlation with the World Health Organization grades, risk stratification in gliomas, and the differentiation of gliomas from other brain tumors. Multiple MRTA studies in gliomas have repeatedly shown high performance of entropy, a measure of the randomness in image intensity values, of either histogram- or gray-level co-occurrence matrix parameters. Similarly, researchers have applied MRTA to other brain tumors, including meningiomas and pediatric posterior fossa tumors.However, the value of MRTA in the clinical use remains undetermined, probably because previous studies have shown only limited reproducibility of the result in the real world. The low-to-modest generalizability may be attributed to variations in MRTA methods, sampling bias that originates from single-institution studies, and overfitting problems to a limited number of samples.To enhance the reliability and reproducibility of MRTA studies, researchers have realized the importance of standardizing methods in the field of radiomics. Another advancement is the recent development of a comprehensive assessment system to ensure the quality of a radiomics study. These two-way approaches will secure the validity of upcoming MRTA studies. The clinical use of texture analysis in brain MRI will be accelerated by these continuous efforts. 相似文献
34.
Shohei Obayashi Katsuyoshi Tomomatsu Mika Urata Jun Tanaka Kyoko Niimi Naoki Hayama Tsuyoshi Oguma Koichiro Asano Yoko Ito 《Internal medicine (Tokyo, Japan)》2022,61(10):1577
Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are common therapeutic agents for EGFR mutation-positive advanced non-small-cell lung cancer. There has been no report of rhabdomyolysis caused by an overdose of EGFR-TKIs. We herein review the existing literature on the subject and report a rare case of rhabdomyolysis due to an overdose of gefitinib, an EGFR-TKI. 相似文献
35.
Koichiro Ota Taiki Watanabe Shuntaro Igarashi Shinnosuke Okazaki Kazuo Kamaike Hiroaki Miyaoka 《RSC advances》2022,12(26):16576
This study reports the stereoselective total syntheses of the antipodes of the unique 3/10 bicyclic skeletal sesquiterpenoids, namely, hypocoprin A and hypocoprin B. The synthesis involved conjugate addition accelerated by trimethylsilyl chloride, construction of the ten-membered ring via the intramolecular SN2 reaction promoted by 1,8-diazabicyclo[5.4.0]undec-7-ene, and osmium-mediated π-facial selective dihydroxylation to functionalize the 1,1-disubstituted alkene.This study reports the stereoselective total syntheses of the antipodes of the unique 3/10 bicyclic skeletal sesquiterpenoids, namely, hypocoprin A and hypocoprin B. 相似文献
36.
Emi Tanaka Tsuneyoshi Ogawa Koichiro Tsutsumi Sayo Kobayashi Toru Nawa Toru Ueki Hiroyuki Okada 《Internal medicine (Tokyo, Japan)》2022,61(13):1963
An 89-year-old woman underwent examinations for leg edema. Blood tests indicated low nutrition and low pancreatic enzymes, and a stool examination indicated fatty stool. Computed tomography showed pleural effusion, ascites, and cystic lesions in the pancreatic head and mural nodules within the cysts. Pancreatic juice cytology revealed adenocarcinoma. The diagnosis was pancreatic exocrine insufficiency caused by intraductal papillary mucinous carcinoma. The patient did not wish to undergo surgery. Therefore, diuretics, component nutrients, and pancreatic exocrine replacement therapy using pancrelipase were initiated. After starting treatment, her leg edema, pleural effusion, and ascites disappeared, and her activities of daily living improved markedly. 相似文献
37.
38.
Teruhiko Imamura Toshihide Izumida Masakazu Hori Shuhei Tanaka Koichiro Kinugawa 《The Journal of international medical research》2022,50(7)
Cardiac amyloidosis usually presents with diastolic dysfunction, but sometimes systolic dysfunction develops, particularly at its advanced stage. However, the therapeutic strategy for patients with cardiac amyloidosis and systolic dysfunction remains unknown. We report a 77-year-old man who was diagnosed with wild-type cardiac amyloidosis and systolic dysfunction with a left ventricular ejection fraction of 27%. Following 6-month medical therapy of tafamidis 80 mg and neurohormonal blockers (carvedilol 5.0 mg, enalapril 2.5 mg, and spironolactone 25 mg), the left ventricular ejection fraction improved to 55%. Tafamidis-incorporated neurohormonal blocker therapy might be a promising strategy to facilitate cardiac reverse remodeling in patients with cardiac amyloidosis and systolic dysfunction. 相似文献
39.
Asako Kitahara Akinori Ebihara Shohei Obayashi Yukihiro Horio Yoshitaka Ono Tomohiro Yoshikawa Naoki Okada Jun Tanaka Hiroto Takiguchi Naoki Hayama Yoko Ito Tsuyoshi Oguma Ichiro Kuwahira Koichiro Asano 《Internal medicine (Tokyo, Japan)》2022,61(8):1219
A 44-year-old man developed coronavirus disease 2019 (COVID-19) pneumonia during immunochemotherapy consisting of carboplatin, paclitaxel, and pembrolizumab for non-small cell lung cancer. Low-grade fever, followed by mild hypoxemia, and febrile neutropenia, were observed, and granulocyte colony-stimulating factor (G-CSF) was administered until the recovery of neutropenia, when he developed a high fever, severe hypoxemia, and hypotension accompanied by consolidation in the bilateral lungs. His conditions promptly improved after treatment including hydrocortisone and the primary and metastatic tumors remained regressed for 10 months without further treatment. Post-COVID-19 organizing pneumonia during cancer immunochemotherapy can be aggravated by immune-checkpoint inhibitors and G-CSF. 相似文献
40.
Oguma T Asano K Shiomi T Fukunaga K Suzuki Y Nakamura M Matsubara H Sheldon HK Haley KJ Lilly CM Drazen JM Yamaguchi K 《American journal of respiratory and critical care medicine》2002,165(3):382-386
Prostaglandins and thromboxanes are important modulators of airway physiology. The synthesis of these mediators depends on two isoforms of cyclooxygenase (COX), constitutive COX-1 and inducible COX-2. COX-2 expression has been observed in various inflammatory diseases, but not all aspects of the expression and the role of COX-2 in conditions of allergic inflammation such as asthma are clear. In the present study, we examined the 72-h kinetics of the expression of COX-isoform mRNA in ovalbumin-sensitized and -challenged guinea-pig lungs. The sensitized animals showed a robust and transient induction of COX-2 mRNA expression within 1 h after ovalbumin challenge, whereas their COX-1 mRNA levels remained unchanged. Upregulation of the level and activity of COX-2 protein followed the induction of COX-2 mRNA. Lung slices harvested from ovalbumin-challenged animals released more prostaglandin D(2) and prostaglandin E(2) spontaneously or in response to A23187 (10 microM) ex vivo than did those from unchallenged animals. This response was significantly blocked by the COX-2 selective inhibitors, NS-398 and JTE-522. In vivo administration of NS-398 significantly inhibited the accumulation of eosinophils and neutrophils in the lungs. In conclusion, de novo COX-2 expression during allergic inflammation modifies prostanoid synthesis in the lung and airway pathophysiology. 相似文献