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91.
Yosuke Tsuruga Toshiya Kamiyama Hirofumi Kamachi Tatsuya Orimo Shingo Shimada Akihisa Nagatsu Yoh Asahi Yuzuru Sakamoto Tatsuhiko Kakisaka Akinobu Taketomi 《World journal of gastrointestinal surgery》2021,13(2):153-163
BACKGROUNDPreoperative portal vein embolization (PVE) is a widely used strategy to enable major hepatectomy in patients with insufficient liver remnant. PVE induces hypertrophy of the future liver remnant (FLR) and a shift of the functional reserve to the FLR. However, whether the increase of the FLR volume (FLRV) corresponds to the functional transition after PVE remains unclear.AIMTo investigate the sequential relationship between the increase in FLRV and functional transition after preoperative PVE using 3-dimensional (3D) computed tomography (CT) and 99mTc-galactosyl-human serum albumin (99mTc-GSA) single-photon emission computed tomography (SPECT) fusion images. METHODSThirty-three patients who underwent major hepatectomy following PVE at the Department of Gastroenterological Surgery I, Hokkaido University Hospital between October 2013 and March 2018 were enrolled. Three-phase dynamic multidetector CT and 99mTc-GSA SPECT scintigraphy were performed at pre-PVE, and at 1 and 2 wk after PVE; 3D 99mTc-GSA SPECT CT-fused images were constructed from the Digital Imaging and Communications in Medicine data using 3D image analysis system. Functional FLRV (FFLRV) was defined as the total liver volume × (FLR volume counts/total liver volume counts) on the 3D 99mTc-GSA SPECT CT-fused images. The calculated FFLRV was compared with FLRV.RESULTSFFLRV increased by a significantly larger extent than FLRV at 1 and 2 wk after PVE (P < 0.01). The increase in FFLRV and FLRV was 55.1% ± 41.6% and 26.7% ± 17.8% (P < 0.001), respectively, at 1 wk after PVE, and 64.2% ± 33.3% and 36.8% ± 18.9% (P < 0.001), respectively, at 2 wk after PVE. In 3 of the 33 patients, FFLRV levels decreased below FLRV at 2 wk. One of the three patients showed rapidly progressive fatty changes in FLR. The biopsy at 4 wk after PVE showed macro- and micro-vesicular steatosis of more than 40%, which improved to 10%. Radical resection was performed at 13 wk after PVE. The patient recovered uneventfully without any symptoms of pos-toperative liver failure.CONCLUSIONThe functional transition lagged behind the increase in FLRV after PVE in some cases. Evaluating both volume and function is needed to determine the optimal timing of hepatectomy after PVE. 相似文献
92.
The epidemiology, etiology, clinical manifestations, diagnostic approach, and therapeutic choices may be quite different for infections that occur in elderly patients compared with those that occur in younger adults. Given these variables, it is essential for clinicians who care for older patients to understand how to prescribe antibiotics appropriately for this population. This article examines the unique characteristics of infections in the elderly as well as provides recommendations on the use of specific antibiotic agents commonly used to treat infections in geriatric patients. 相似文献
93.
Toshihiro Kawamoto Koji Matsuno Keiichi Arashidani Masahiro Yoshikawa Fujio Kayama Yasushi Kodama 《Archives of environmental contamination and toxicology》1993,25(4):534-538
The personal exposure to NO2 generated from various heaters and cooking stoves were studied, using 85 university students. The students attached NO2 filter badges to their chests or collars and wrote down the period of time for heating and cooking for 1 week. Types of heaters and smoking habits were described through a questionnaire. The urinary hydroxyproline/creatinine ratio (HOP/C) was examined as a biomarker for health effects. The outdoor NO2 concentration during the study period was 13.5–13.7 g/m3. Smoking and the usage of electric heaters did not affect the exposure to NO2. Exposure increased according to the length of time kerosene heaters or oil fan heaters were used. The NO2 concentration during the heating by a kerosene heater and an oil fan heater was calculated to be 219 and 474 g/m3, respectively. The correlation between the period of cooking and personal exposure was also observed. The NO2 levels during cooking were calculated to be 290 g/m3. Using these calculated values of NO2 concentration, it is possible to presume the personal exposure levels from the length of time heaters and cooking stoves are used even if the subjects do not attach the filter badges. Neither smoking nor exposure to NO2 were associated with the increase of urinary HOP/C. 相似文献
94.
通过检测E6变体在HPV16阳性的宫颈非典型增生(CIN)和宫颈浸润癌(ICC)患者中的分布,研究其致癌能力.方法:用PCR和双脱氧终止荧光法检测了42例E6基因点突变及其编码氨基酸改变,统计分布差异.结果:2例(5%)为原型,40例(95% )的E6DNA序列中含有1至3个点突变,导致13类E6氨基酸残基改变,组合成17种(94%)HPV16变体.出现频率较高的4种变体在CIN和ICC病例中共同存在,分布无显著性差异(P>0.05).DNA的点突变数在CIN和ICC病例中的分布也无显著性差异(P>0.05).结论:HPV16E6的变体多于原型,但是变体和原型的致癌能力没有明显差别. 相似文献
95.
Junichi Okada Hiroshi Oonishi Kyosan Yoshikawa Keiko Imaseki Kimiichi Uno Jun Itami Noboru Arimizu 《Annals of nuclear medicine》1994,8(2):109-113
To evaluate positron emission tomography with18F-fluorodeoxy glucose (FDG-PET) as an diagnostic tool to determine tumor viability after anticancer therapy, fourteen patients were examined by FDG-PET after the end of the treatment. The lesions with residual viable tumor cells showed higher uptake of FDG than surrounding normal soft tissue. The lesions, in which tumor viability was lost or very low, showed higher uptake of FDG in four cases and similar uptake to normal soft tissue in three cases. The residual increased uptake of FDG was considered to be caused by remaining tumor cells and/or inflammatory reaction to anticancer treatment. FDG-PET after anticancer treatment should be interpreted by considering the reaction due to the treatment and the partial volume artifact of PET caused by the limited spatial resolution. 相似文献
96.
97.
Hayashi M Matsui O Ueda K Kawamori Y Kadoya M Yoshikawa J Gabata T Takashima T Nonomura A Nakanuma Y 《AJR. American journal of roentgenology》1999,172(4):969-976
OBJECTIVE: The purpose of this study is to evaluate the correlation between the intranodular blood supply revealed by CT during intraarterial injection of contrast medium, mainly using helical CT, and the grade of malignancy of hepatocellular nodules associated with liver cirrhosis as classified by the International Working Party of the World Congress of Gastroenterology. SUBJECTS AND METHODS: We studied 201 histologically proven nodules (101 resected and 100 biopsied nodules), including 47 low-grade dysplastic nodules (low-DNs), 56 high-grade dysplastic nodules (high-DNs), 24 well-differentiated hepatocellular carcinomas (wd-HCCs), and 74 moderately or poorly differentiated HCCs (mp-HCCs), in 139 cirrhotic patients. Findings on CT during arterial portography (n = 201) and CT during hepatic arteriography (n = 74) were reviewed and compared with the histologic diagnosis. RESULTS: CT findings were classified into four types relative to the surrounding liver: type A (isodense), type B (slightly hypodense), type C (partially hypodense), and type D (markedly hypodense) on CT during arterial portography and type I (isodense), type II (hypodense), type III (partially hyperdense), and type IV (hyperdense) on CT during hepatic arteriography. On CT during arterial portography, the distributions of each type were low-DN (n = 47 [A, n = 36; B, n = 8; C, n = 3]), high-DN (n = 56 [A, n = 18; B, n = 20; C, n = 10; D, n = 8]), wd-HCC (n = 24; [B, n = 4; C, n = 13; D, n = 7]), and mp-HCC (n = 74 [D, n = 74]). On CT during hepatic arteriography, the distributions were low-DN (n = 26 [I, n = 18; II, n = 7; III, n = 1]), high-DN (n = 19 [I, n = 6; II, n = 7; III, n = 4; IV, n = 2]), wd-HCC (n = 15 [I, n = 1; III, n = 8; IV, n = 6]), and mp-HCC (n = 14 [IV, n = 14]). We found a statistically significant correlation between the four types and the grade of malignancy of these nodules. CONCLUSION: Findings on CT during arterial portography and CT during hepatic arteriography correlated positively with histologic grading when overlap in appearance between dysplastic nodules and HCCs occurred. The concept revealed in this study can apply to diagnoses made on the basis of Doppler sonography, dynamic CT, and MR imaging. 相似文献
98.
Inoue Y Katayama N Yoshioka N Yoshikawa K Kashima M Shimizu T Tsukune Y Ohtomo K 《Annals of nuclear medicine》1999,13(6):453-456
The aim of this study was to evaluate breast parenchymal activity on scintimammography with bone-seeking agents and 99mTc-MIBI. Scintimammography was performed with bone-seeking agents in 61 patients and with 99mTc-MIBI in 33 patients. Activity in the breast parenchyma contralateral to the suspected lesion was visually assessed by two independent observers. Increased breast parenchymal activity was shown in 19 of 61 patients examined with bone-seeking agents, while it was demonstrated in only two of 33 patients examined with 99mTc-MIBI. Breast parenchymal activity of bone-seeking agents was higher in patients aged 50 years or younger than in those older than 50. Increased parenchymal activity of bone-seeking agents may disturb visualization of primary breast cancer especially in relatively young patients. Low parenchymal activity is suggested to be a favorable characteristic of 99mTc-MIBI as a scintimammographic agent. 相似文献
99.
Yoshikawa H Myoui A Ochi T Araki N Ueda T Kudawara I Nakanishi K Tanaka H Nakamura H 《Seminars in musculoskeletal radiology》1999,3(2):183-190
The incidence, distribution, time of appearance, and radiologic findings of bone metastases from soft tissue sarcomas, exclusive of lymphomas, were evaluated in 320 patients with soft tissue sarcomas. Thirty patients (9.4%) had evidence of 58 bone metastases. Five of 30 patients presented with metastases, and 25 of 30 patients developed metastases up to 66 months after presentation with a mean time interval of 21.3 months. The incidence of skeletal metastases differed among histologic subtypes of sarcomas; alveolar soft part sarcoma (5 of 8), dedifferentiated liposarcoma (2 of 4), angiosarcoma (2 of 4), and rhabdomyosarcoma (5 of 16) tended to show a higher incidence of bone metastases. The sarcomas metastasized to the regional bones close to the primary tumor in 16 (53%) of 30 patients and to the axial bones in 18 (60%). On conventional radiographs, the osseous metastases demonstrated predominantly osteolytic changes, and evidence of pathological fracture was observed in 31% of 58 metastases. 相似文献
100.
Uchida T Tomita Y Anzai K Zhang QW Yoshikawa M Kishihara K Nomoto K Yasui H 《Transplantation》1999,68(11):1721-1727
An essential role of murine CD4+ T cells in immune reactivity and skin graft rejection in discordant xenogeneic combinations have been reported. Our study was conducted to further clarify the roles of CD4+ and CD8+ T cells in discordant skin xenograft rejection, by using CD4 and CD8 knockout [C57BL/6 Cr Slc (B6; H-2b) background] mice. When human skins were grafted on CD8 knockout mice or B6 mice, both hosts rejected human skin grafts within 12 days after grafting. By contrast, survival of human skin grafts was significantly prolonged in CD4 knockout mice (mean survival times=19.3+/-(SD) 1.6 days; median 19 days). Fully allogeneic C3H/He Slc (H-2k) skin grafts were rejected within 14 days in CD4 knockout mice, suggesting that non-CD4+ T cells in CD4 knockout mice were immunocompetent for allograft rejection. In spleens of these recipient mice, CD8+ T cells seemed to be activated 10 days after human skin grafting. Immunohistological analysis revealed the infiltration of CD8+ T cells at the site of transplanted human skin on CD4 knockout mice. To further examine the role of CD8+ T cells in CD4 knockout mice, human skin grafting was performed on day 0 followed by administration of anti-CD8 monoclonal antibody on days 0, 5, and 14. The administration of anti-CD8 monoclonal antibodies caused the significant prolongation of human skin graft survival. These results indicate the following two conclusions: (1) CD4+ T cells have an essential role in rejecting discordant human skin xenografts rapidly and (2) however, CD8+ T cells also are capable of rejecting discordant human skin xenografts. 相似文献