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941.
Yosuke Watanabe Fumiyuki Yamasaki Yoshinori Kajiwara Takeshi Takayasu Ryo Nosaka Yuji Akiyama Kazuhiko Sugiyama Kaoru Kurisu 《European journal of radiology》2013
Purpose
We assessed whether a high b-value DWI at b = 4000 s/mm2 would discriminate the histopathological differentiation of the tumor grade of meningiomas, and also focused on the relationship between radiologic features and the tumor grade.Materials and methods
We acquired DWI at 3T with b = 1000 and b = 4000 s/mm2 in 77 patients (42, 31 and 4 patients were WHO grades I (G1), II (G2), and III (G3), respectively). The apparent diffusion coefficient (ADC) was measured by placing multiple regions of interest (ROIs) on ADC maps. The ADC values of each tumor were determined preoperatively from several ROIs, and expressed as the minimum (ADCMIN), mean (ADCMEAN), and maximum absolute values (ADCMAX). We evaluated the relationship between ADCs and histological findings, and assessed the radiologic features such as tumor location, tumor size, presence/absence of peritumoral edema, shape of the tumor, presence/absence of bone destruction or hyperplasia, status of contrast enhancement, presence/absence of calcification and cyst.Results
ADCs of the meningiomas were inversely correlated with the histological grade of meningiomas. According to results of the discriminant analysis, the apparent log likelihood value was greatest for ADCMIN at b = 4000. Furthermore, only the ADCMIN value at b = 4000 was significantly correlated with the histological grade of meningiomas when we performed a multiple logistic regression analysis to identify the significant independent factors such as shape of tumor, presence/absence of bone destruction, status of contrast enhancement, presence/absence of cyst and ADCMIN at b = 4000.Conclusion
A meningioma with a low ADCMIN at a high b-value might imply a high-grade meningioma. 相似文献942.
对金仓鼠肝区作8MeV电子束40Gy一次照射,分别对照射后1,2,3天,1,4,8周和9个月的活体动物肝脏置6.34T磁场强度的波谱仪作31P-磁共振波谱分析,然后摘出动物肝脏作组织学对照研究。结果表明:以β-ATP信号强度为基准计算的各峰值信号强度比中,照射后1~3天的PME增高,照射后1周以上的各组γ-ATP和α-ATP均示降低;细胞内pH示照射后1天升高,2和3天随之降低,照后1~4周再度升高后与前者有显著性差异(P<0.05)。组织学图像示肝细胞点状坏死,肝细胞脂肪变性,肝细胞萎缩等。作者认为:31P-磁共振波谱分析对放射性肝损伤的肝能量代谢测定是准确和有价值的。 相似文献
943.
Iida T Yasuda M Miyazawa M Fujita M Osamura RY Hirasawa T Muramatsu T Murakami M Saito K Mikami M 《Archives of gynecology and obstetrics》2008,277(6):539-546
Material and methods We analyzed the expression of hypoxia inducible factor-1α (HIF-1α) and glucose transporter-1 (GLUT-1) by immunohistochemistry
in ovarian serous and mucinous tumors from the point view of the histological characteristics and acquisition of malignancy.
A total of 102 ovarian tumors were examined, composed of 31 adenomas (serous 17 and mucinous 14), 32 borderline tumors (serous
13 and mucinous 19), and 39 adenocarcinomas (serous 21 and mucinous 18).
Results The overall positive ratios were as follows: HIF-1α, 74% of
adenomas, 91% of borderline tumors, and 100% of adenocarcinomas; and GLUT-1, 68% of adenomas, 95% of borderline tumors, and
100% of adenocarcinomas. Comparing serous tumors and mucinous tumors, there was no significant difference in the positive
ratios of HIF-1α and GLUT-1 of adenomas, borderline tumors, and adenocarcinomas. However, both markers were more strongly
expressed in serous adenocarcinomas (HIF-1α, 3 + 100%; GLUT-1, 3 + 76%) than in mucinous adenocarcinomas (HIF-1α, 3 + 61%;
GLUT-1, 3 + 28%). The results of immunoblotting and mRNA expression level analyses corresponded with those of immunohistochemical
expression profiles. DNA binding assay also demonstrated that HIF-1 is more commonly activated in serous adenocarcinomas than
in mucinous adenocarcinomas.
Conclusion HIF-1α and GLUT-1 expressions seemed to be coordinated to adapt ovarian tumor cells into hypoxic conditions in close association
with the acquisition of malignancy. We consider that the relatively strong expression of both markers in serous tumors compared
with mucinous tumors is related to the difference in their histological characteristics. 相似文献
944.
945.
Ohara M Shimizu Y Satoh H Kasai T Takano S Fujiwara R Furusawa Y Kameda S Matsumura T Narimatsu H Kusumi E Kodama Y Kami M Murashige N Suzuki M 《The journal of obstetrics and gynaecology research》2008,34(2):189-194
AIM: Japan has a shortage of tertiary medical care facilities for maternal and fetal medicine. Establishment of efficient medical transport systems is needed for pregnant women and fetuses with severe complications. Maternal transport by helicopters is expected to shorten transportation time to advanced facilities, although its feasibility has not yet been evaluated. The aim of the present study was to investigate the status of maternal helicopter transport, and conditions of the pregnant patients and children transferred by helicopter to Kameda Medical Center (KMC). METHODS: Between August 2005 and July 2006, 26 pregnant women were transported by helicopters to KMC. RESULTS: The median net flight time was 24 min (range 15-29 min), and the median of estimation of ground transportation time was 125 min (range 90-180 min). The causes for transfers were preterm labor in eight, preterm premature rupture of the membrane in five, cervical incompetence in five, pre-eclampsia in three and other medical reasons in five. Five of the 26 patients were discharged with restored stability of pregnancy. The remaining 21 patients underwent delivery at KMC. The median gestational age was 26 weeks (range 22-33 weeks) at the time of transfer and 31 weeks (range 22-37 weeks) at delivery. Four of 26 neonates who were born at KMC died after birth due to severe premature or congenital anomaly. Seventeen of the remaining 22 neonates, including 10 twins, received treatment in the neonatal intensive care unit. All of the 22 neonates and all the mothers were discharged in good condition. No patients developed any complications requiring treatment during flights. CONCLUSION: Helicopter transfer is feasible for pregnant patients with severe complications. 相似文献
946.
Kitao K Yoshida S Kennedy S Takemura N Sugimoto M Deguchi M Ohara N Maruo T 《Reproductive sciences (Thousand Oaks, Calif.)》2007,14(4):349-357
Endometrial cancer is associated with both EGFR and HER2 receptor activation. The EGFR and HER2 genes could be disease susceptibility candidate genes for this cancer. This study was conducted to investigate a possible association between EGFR and HER2 gene polymorphisms and endometrial cancer and the influence of these polymorphisms on the clinical outcome of endometrial cancer patients in a Japanese population. The authors compare the genotype distributions and allele frequencies of the EGFR +2073 A/T and HER2 +655 A/G polymorphisms in 116 endometrial cancer patients and 213 controls using polymerase chain reaction-restriction fragment length polymorphism (RFLP) analysis. RFLP results were confirmed by direct DNA sequencing. Of the 116 patients, 76 (65.5%) could be followed up. Disease-free survival estimates were computed using the Kaplan-Meier method, and differences between survival periods were assessed using the log-rank test. No significant differences were observed in either genotype distributions or allele frequencies in the EGFR +2073 A/T and HER2 +655 A/G polymorphisms between endometrial cancer patients and controls. The stratification by histological types and staging failed to identify significant differences between endometrial cancer patients and controls. No statistical differences were noted between these polymorphisms and disease-free survival (Kaplan-Meier log-rank test P = .55 and .66, for the EGFR +2073 A/T and HER2 +655 A/G, respectively). These results suggest that the EGFR +2073 A/T and HER2 +655 A/G polymorphisms are not associated with endometrial cancer in a Japanese population. These conclusions are based on relatively small numbers and will require verification from additional independent studies. 相似文献
947.
Miura K Fujibuchi W Ishida K Naitoh T Ogawa H Ando T Yazaki N Watanabe K Haneda S Shibata C Sasaki I 《Surgery today》2011,41(2):175-182
The apoptosis and antiapoptotic signaling pathways are important for regulating carcinogenesis and cancer progression, and for determining prognosis. Molecules involved in apoptosis represent potential cancer diagnostic markers and therapeutic targets. The inhibitor of apoptosis protein (IAP) family includes several important molecules involved in apoptosis that might represent such targets. Increasing evidence has demonstrated that the IAP family of proteins is integral for antiapoptotic and nuclear factor-κB signal transduction, and enhanced expression of IAPs contributes to colon carcinogenesis and its poor prognosis, as well as to drug resistance of tumors. X-linked IAP, cIAP1, cIAP2, and survivin are prognostic markers of colorectal cancer, and survivin and cIAP2 are also utilized to predict the effect of anticancer treatment in colorectal cancer patients. Novel therapies such as YM155 and LY2181308 targeting survivin, AEG35156 and phenoxodiol targeting X-linked IAP, AT-406 as a Smac mimetic, and survivin peptides are currently being evaluated in clinical trials. This report reviews the involvement of the IAP family in colorectal adenocarcinoma in order to summarize the role of the IAP family members as diagnostic and therapeutic targets, and to provide an overview of the future course of research in this area. 相似文献
948.
Longitudinal evaluation of local muscle conditions in a rat model of gastrocnemius muscle injury using an in vivo imaging system 下载免费PDF全文
Kazuhide Inage Yoshihiro Sakuma Kazuyo Yamauchi Akiko Suganami Sumihisa Orita Go Kubota Yasuhiro Oikawa Takeshi Sainoh Jun Sato Kazuki Fujimoto Yasuhiro Shiga Kazuhisa Takahashi Seiji Ohtori Yutaka Tamura 《Journal of orthopaedic research》2015,33(7):1034-1038
This study aimed to evaluate the time course of local changes during the acute phase of gastrocnemius muscle strain, in a rat model, using an in vivo imaging system. Thirty‐eight, 8‐week‐old Sprague‐Dawley male rats were used in our study. Experimental injury of the right gastrocnemius muscle was achieved using the drop‐mass method. After inducing muscle injury, a liposomally formulated indocyanine green derivative (LP‐iDOPE, 7 mg/kg) was injected intraperitoneally. We evaluated the muscle injuries using in vivo imaging, histological examinations, and enzyme‐linked immunosorbent assays. The fluorescence peaked approximately 18 h after the injury, and decreased thereafter. Histological examinations revealed that repair of the injured tissue occurred between 18 and 24 h after injury. Quantitative analyses for various cytokines demonstrated significant elevations of interleukin‐6 and tumor necrosis factor‐α at 3 and 18 h post‐injury, respectively. The time course of fluorescence intensity, measured using in vivo imaging, demonstrated that the changes in cytokine levels and histopathologic characteristics were consistent. Specifically, these changes reached peaked 18 h post‐injury, followed by trends toward recovery. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1034–1038, 2015. 相似文献
949.
Fractalkine expression and the recruitment of CX3CR1+ cells in the prolonged mesangial proliferative glomerulonephritis 总被引:11,自引:0,他引:11
Ito Y Kawachi H Morioka Y Nakatsue T Koike H Ikezumi Y Oyanagi A Natori Y Natori Y Nakamura T Gejyo F Shimizu F 《Kidney international》2002,61(6):2044-2057
BACKGROUND: We established the reversible and the prolonged models of mesangial proliferative glomerulonephritis (GN) with anti-Thy 1 antibody 1-22-3. However, the essential factors leading to the prolonged glomerular alterations have not been identified. METHODS: The expressions of several chemokines and cytokines were compared in the reversible and the prolonged models. Expression of fractalkine and the number of the fractalkine receptor CX3CR1-positive cells in the glomeruli in the prolonged model were significantly higher than those in the reversible model. Then, the localization of fractalkine and the characteristics of CX3CR1+ cells were analyzed in glomeruli. To elucidate the significance of the fractalkine expression, we analyzed the expression in the model treated with angiotensin II receptor antagonist, candesartan. RESULTS: Immunostaining of fractalkine was detected on endothelial cells on the fifth day, and fractalkine staining also was detected in the mesangial area on day 14. Major parts of the CX3CR1+ cells in the glomeruli were macrophages, especially ED3+ cells. Candesartan treatment ameliorated the glomerular morphological findings at six weeks after disease induction. Although the treatment did not ameliorate the morphological finding at two weeks, decreased expression of fractalkine and CX3CR1+ were already detected at two weeks in rats treated with candesartan. CONCLUSIONS: Fractalkine expression and the recruitment of CX3CR1+ cells in glomeruli might play an important role in the development of the prolonged disease. These expressions could be predictors of the prolonged disease of the mesangial proliferative glomerulonephritis. 相似文献
950.
Shibata T Yasuoka T Inoue K Ikuta T Bito Y 《General thoracic and cardiovascular surgery》2007,55(10):440-441
We hereby present our technique for using the self-retaining flexible arm retractor and its attachments for mitral valve exposure.
The Aortic Valve Assistant, which was developed for aortic valve exposure, is also very useful for exposure of the inferior
wall of the left atrium. Our modified atrial hook provides excellent exposure of the anterior mitral annulus. Extensive dissection
and the combined use of the flexible arm and attachments allows us comfortable access for mitral valve operations. 相似文献