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排序方式: 共有1803条查询结果,搜索用时 218 毫秒
101.
Yuki Matsumoto Mikiko Kobayashi Kunihiko Shingu Ayako Tateishi Maki Ohya Kenji Sano Tatsuya Negishi Shohei Shigeto Tatsuya Kobayashi Yosuke Hara Yukinari Kakizawa Hiroyuki Kanno 《Neuropathology》2020,40(5):507-514
Pleomorphic xanthoastrocytomas (PXAs) are rare low-grade astrocytic tumors that typically present as superficial nodular cystic tumors of the cerebrum attached to the leptomeninx. Histologically, they are pleomorphic, hypercellular glial neoplasms. Despite the presence of microscopic pleomorphism, patients’ postoperative prognosis is generally good. Anaplastic PXAs (APXAs) have a high mitotic index and patients with APXAs have a worse prognosis than patients with PXAs. Here, we report an autopsy case of APXA initially diagnosed as PXA. After gross total resection, the tumor recurred and was diagnosed as an APXA; thereafter, the patient died. An autopsy revealed that the tumor had relapsed at the primary site and had spread to the leptomeningeal space while concurrently invading the cerebrum including the periventricular area forming multifocal lesions. The histological findings of the autopsy were similar to those for epithelioid glioblastoma (EGBM) and small cell glioblastoma (SCGBM). In particular, the periventricular area with multifocal lesions was composed of SCGBM-like cells. It has been shown that multifocal lesions are frequently identified in patients with SCGBM. This is the first histopathologically confirmed case of APXA-related tumor presenting with periventricular extension and multifocal lesion formation. The periventricular extension might be a feature of PXAs and APXAs. However, suspected periventricular spread on imaging in past cases of PXAs and APXAs might instead represent the malignant transformation of these tumors to glioblastoma-like high-grade tumors, which often show SCGBM-like histological patterns. 相似文献
102.
Chenzhu Yin Masakazu Mukaida Shohei Horike Kazuhiro Kirihara Shogo Yamane Zhenya Zhang Qingshuo Wei 《RSC advances》2022,12(11):6748
This paper shows how protonated 3,4-ethylene dioxythiophene moieties can be used as an end group to make organic conductors. An organic semiconductor 2,5-bis(5-(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-3-dodecylthiophen-2-yl)thieno[3,2-b]thiophene is designed and synthesized. This molecule could be doped by protonic acid in both solution and solid-state, resulting in a broad absorption in the near-infrared range corresponding to polaron and bipolaron absorption. Electrical conductivity of ca. 0.1 S cm−1 was obtained at 100 °C (to avoid the water uptake by the acid). The adducts with protons bound at the end-thiophene α-position were confirmed by 1H Nuclear Magnetic Resonance spectra.The use of protonated 3,4-ethylenedioxythiophene moieties as an end group could be a promising approach to prepare organic conductors. 相似文献
103.
Differential diagnosis of pancreatic cancer and focal pancreatitis by using EUS-guided FNA 总被引:11,自引:0,他引:11
Takahashi K Yamao K Okubo K Sawaki A Mizuno N Ashida R Koshikawa T Ueyama Y Kasugai K Hase S Kakumu S 《Gastrointestinal endoscopy》2005,61(1):76-79
BACKGROUND: Despite advances in diagnostic imaging techniques, the differentiation between pancreatic cancer and focal pancreatitis remains difficult. This study evaluated the effectiveness of EUS-guided FNA in the differential diagnosis between pancreatic cancer and focal pancreatitis, with particular reference to detection of the K-ras point mutation. METHODS: The study included 62 consecutive patients with pancreatic ductal cancer and 15 patients with focal pancreatitis demonstrated as a pancreatic mass lesion by EUS. RESULTS: Sensitivity, specificity, overall accuracy, positive predictive value, and negative predictive value of cytopathologic diagnosis were 82%, 100%, 86%, 100%, and 58%, respectively. Sensitivity, specificity, overall accuracy, positive predictive value, and negative predictive value of histopathologic diagnosis were 44%, 100%, 55%, 100%, and 32%, respectively. The K-ras point mutation was found in 74% of pancreatic cancers and 0% of focal pancreatitis lesions. No complication of EUS-guided FNA was observed. CONCLUSIONS: EUS-guided FNA is useful for the differential diagnosis of pancreatic mass lesions caused by pancreatic cancer and focal pancreatitis. Analysis for the K-ras point mutation in specimens obtained by EUS-guided FNA may enhance diagnostic accuracy in indeterminate cases. 相似文献
104.
105.
Kentaro Wakamatsu Nobuhiko Nagata Hiroyuki Kumazoe Keishi Oda Hiroshi Ishimoto Michihiro Yoshimi Shohei Takata Minako Hamada Yoshifusa Koreeda Kouji Takakura Miwa Ishizu Makiko Hara Shinji Ise Miiru Izumi Takashi Akasaki Sanae Maki Masaharu Kawabata Hiroshi Mukae Masayuki Kawasaki 《Respiratory investigation》2017,55(1):16-23
Background
The prognostic significance of serial measurements of serum KL-6 levels in patients with idiopathic pulmonary fibrosis (IPF) is unclear; hence, it was assessed in this study.Methods
Medical records of 66 patients with IPF, who were not treated with pirfenidone prior to enrollment, were retrospectively reviewed for information on clinical progress, forced vital capacity (FVC), survival, and serum KL-6 levels. We assessed initial serum levels of KL-6, serial changes in serum KL-6 levels, yearly decline in FVC (ΔFVC), and the rate of decline (%ΔFVC).Results
Patients with increased serum KL-6 levels during follow-up had a significantly steeper decline in ΔFVC than those with no KL-6 increase (?201 vs. ?50.7 ml/year; p=0.0001). Patients with both initial serum KL-6 ≥1000 U/ml and serial increases in serum KL-6 had the steepest decline, while those with both initial serum KL-6 <1000 ml and no serial increases in KL-6 had the least decline in ΔFVC and %ΔFVC. Relative to the non-increased KL-6 group, survival in the increased KL-6 group tended to be poorer (p=0.0530). Patients with both initial serum KL-6 values <1000 U/ml and no serial increase in KL-6 had more favorable prognoses than those with serial increases in KL-6 or initial serum KL-6 values ≥1000 U/ml (p<0.0044). Prognosis was significantly poorer in patients with serial KL-6 changes >51.8 U/ml/year than in those with serial KL-6 changes <51.8 U/ml/year (p=0.0009).Conclusion
Thus, serial serum KL-6 measurements can be useful for assessing prognosis in patients with IPF. 相似文献106.
107.
Idiopathic osteosclerosis (IO) is a localized, well-defined, intrabony radiopaque lesion within cancellous bone. The causes of IO are still unknown and most lesions are nonexpansile and asymptomatic, so they are often detected incidentally on radiographic examination for other purposes. In the case of jaw lesions, IO is considered to be of no clinical significance and usually requires no treatment. This paper describes two clinical cases about the long-term treatments and observations of mandibular IO in adolescents. The lesions were associated with abnormal tooth root formation and tooth malposition. In these cases, the orthodontic treatments finished successfully without any complication despite the lesions. IO in the jaw needs regular follow-up to ensure normal orofacial development during adolescence. 相似文献
108.
This study examined the difference in dietary intake between middle-aged and elderly Japanese and Chinese. Volunteers aged
50–79 living in two cities in both Japan and China were recruited in local community service centers and were asked to complete
a 3-day diet recording. The final results were based on 356 subjects (166 Chinese and 190 Japanese). In men, the Japanese
subjects significantly consumed more energy, with a large proportion of the energy coming from carbohydrates, dietary fiber,
vitamin A, vitamin B2, vitamin C and they consumed less iron, and a lower proportion of energy from protein and fat than in the Chinese subjects.
In women, the Japanese subjects had significantly higher intakes of energy, the proportion of energy from carbohydrates, dietary
fiber, calcium, vitamin A, vitamin B1, vitamin B2, vitamin C and they consumed less iron, with the proportion of energy from protein and from fat in comparison with the Chinese
women. Fat intake provided more than 29% of the total dietary energy in Chinese subjects. Daily intake of food items was significantly
greater in the Japanese participants, both men and women (18.54 ±2.85, 20.11 ± 2.40, respectively), than in the Chinese subjects
(14.11 ± 3.62, 15.51 ± 4.15, respectively) (p<0.01 by Mann WhitneyU-test). The present study suggests that the middleaged and elderly Chinese subjects should increase their variety of foods
consumed while decreasing their consumption of high-fat foods. For the Japanese subjects, the higher intake of total calories
among the woman should also be noted. 相似文献
109.
Koyama Shohei; Tsujii Hirohiko; Yokota Hikaru; Hotta Soichi; Miyo Yasushi; Fukutomi Hisayuki; Osuga Toshiaki; Tsuji Hiroshi; Okumura Toshiyuki; Ohara Kiyoshi; Kikuchi Masanori 《Japanese journal of clinical oncology》1994,24(3):144-153
Fifteen patients with esophageal carcinoma (superficial, sixcases; advanced, nine cases) were treated with 250 MeV protonbeam irradiation with or without external x-ray irradiation(12 MV linear accelerator) from October, 1985, to May, 1991.Eleven patients were initially treated with x-ray at doses of16.2-50.4 (mean 42.5) Gy, followed by proton beam at doses of30.0-52.9 (mean 37.6) Gy. The other four patients were treatedwith proton beam alone at total doses of 75.0-88.5 (mean 81.4)Gy. The mean total dose for the 15 patients was 80.4 Gy. Asa result, the primary tumor lesions of all 15 patients disappearedand complete responses were obtained. Approximately four tofive months later, nine of the 15 patients developed esophagealulcer formations at the circumferences of their primary lesions.The ulcerations were healed, however, by conservative management.There was no evidence of local recurrence throughout the observationson six cases of superficial carcinoma. Among nine advanced carcinomapatients, three relapsed into esophageal carcinoma. Recurrenceswere observed eight, 16 and 44 months, respectively, after thetreatment. Ten of the 15 patients died, but eight died of otherdiseases. Three of four cases at autopsy did not show any cancercells in irradiated primary lesions. Four of the 15 patientslived for over five years. The results suggest that a high doseof irradiation delivered by a well-defined proton field couldresult in improved local control and long-term survival in esophagealcarcinoma without undue risk of injury to primary and adjacentorgans. 相似文献
110.
Detection of Gastric Cancer Micrometastases in Lymph Nodes by Amplification of Keratin 19 mRNA with Reverse Transcriptase-Polymerase Chain Reaction 总被引:10,自引:0,他引:10