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991.
目的 探讨多体素氢质子磁共振波谱成像(1H-MRS)联合表观扩散系数(ADC)在脑胶质瘤分级诊断、评估肿瘤细胞增殖活性的应用价值。方法 60例脑胶质瘤患者,低级别胶质瘤(LGG)组(Ⅰ、Ⅱ级)22例,高级别胶质瘤(HGG)组(Ⅲ、Ⅳ级)38例。所有患者术前完成多体素1H-MRS及扩散加权成像(DWI)检查。分析瘤体区胆碱(Cho)/肌酸(Cr)、Cho/N-乙酰天门冬氨酸(NAA)、NAA/Cr、瘤体区表观扩散系数(ADCT)、对侧正常脑实质表观扩散系数(ADCH)、相对表观扩散系数(rADC)(rADC=ADCT/ADCH)、Ki-67指数的统计学差异。结果 LGG、HGG瘤体区Cho/Cr、Cho/NAA及ADCT、rADC值的差异均有统计学意义(P<0.01);Cho/Cr联合rADC值的受试者工作特征曲线(ROC)曲线下面积(AUC)最大(AUC=0.92),脑胶质瘤分级诊断敏感度、特异度为92.1%、80.3%。瘤体区... 相似文献
992.
目的 探讨彩色多普勒超声联合三维Hyaline成像对子宫假性动脉瘤(UAP)的诊断价值.资料与方法前瞻性纳入2019年3月—2021年5月四川省妇幼保健院利用彩色多普勒超声结合三维Hyaline玉影成像诊断UAP患者7例,其中1例经MRI证实,6例经MRI及子宫动脉造影证实,观察瘤体的大小及形态,获得瘤腔立体三维图像,... 相似文献
993.
994.
Hwang S Song GW Ha TY Lee YJ Kim KH Ahn CS Sung KB Ko GY Kim MH Lee SK Moon DB Jung DH Park GC Lee SG 《World journal of surgery》2012,36(2):379-385
Background
The high incidence of percutaneous transhepatic biliary drainage (PTBD) tract recurrence after resection of perihilar bile duct cancer (BDC) at a reference single center has suggested the need for endoscopic biliary drainage (EBD) to prevent PTBD-related tumor recurrence. To determine the general applicability of these findings, we validated the risk of PTBD tract recurrence in patients with resected BDC in our high-volume center.Methods
The medical records of 306 patients with perihilar BDC who underwent hepatobiliary resection with curative intent over 10?years were reviewed retrospectively.Results
Of the 306 patients, 293 (95.8%) underwent biliary decompression, 171 (56.1%) by preoperative PTBD, 62 (20.3%) by EBD alone, and 60 (19.7%) by both. Of the 231 patients who underwent PTBD, 160 (69.3%), 62 (26.8%), and 9 (3.9%) had one, two, or three catheters, respectively (mean of 1.3 catheters per patient for a median 23?days). No patient experienced synchronous PTBD tract metastasis, whereas 4 (1.7%) experienced PTBD tract recurrence a median 13.5?months after surgery, with 3 of these patients having an intraabdominal recurrence soon afterward. Only one patient had a solitary tract recurrence without intraabdominal metastasis. These patients survived for a median 25?months, which is comparable to survival outcomes after noncurative resection. No risk factor was significantly associated with PTBD tract recurrence.Conclusions
We think that the risk of PTBD tract recurrence after resection of perihilar BDC is not negligible but is much lower than previously reported. There is no definitive reason to avoid PTBD when it is indicated. 相似文献995.
Chung IS Kim HY Shin YH Ko JS Gwak MS Sim WS Kim GS Lee SK 《Clinical transplantation》2012,26(4):539-543
A characteristic pattern of hemodynamic changes that may occur in reperfusion phase of liver transplantation (LT) is known as post-reperfusion syndrome (PRS). In this study, we determined the frequency of PRS and evaluated possible predictors of PRS. The medical records of 152 patients who underwent living donor LT were reviewed. PRS was defined as a decrease in mean arterial pressure of more than 30% from the baseline value for more than one min during the first five min after reperfusion. The frequency of PRS was determined, and patients were divided into two groups: PRS group and non-PRS group. Donor factors, preoperative and intraoperative recipient factors, and postoperative outcomes were compared between the two groups. PRS occurred in 58 recipients (34.2%). Preoperative model for end-stage liver disease scores of recipients and percentage of graft steatotic changes were higher in PRS group. PRS group showed higher heart rates and lower hemoglobin values preoperatively. Before reperfusion, PRS group received more transfusion and their urine output was less than that of non-PRS group. Postoperatively, peak bilirubin during the first five d after LT was higher in PRS group. In conclusion, both severity of liver disease and graft steatosis may increase risk for PRS in LT. Further prospective studies of PRS in its relationship to outcome are indicated. 相似文献
996.
Onodera M Kawakami H Kuwatani M Kudo T Haba S Abe Y Kawahata S Eto K Nasu Y Tanaka E Hirano S Asaka M 《Surgical endoscopy》2012,26(6):1710-1717
Background
Endoscopic ultrasound (EUS)-guided drainage is widely used to manage pancreatic pseudocysts. Several studies have reported the use of EUS-guided drainage for pancreatic fistula and stasis of pancreatic juice caused by stricture of the pancreatic duct after pancreatic resection.Methods
At the authors’ hospital, 262 patients underwent surgery involving pancreatic resection from April 2005 to March 2010. In 90 of these patients (34%), a grade B or C postoperative pancreatic fistula developed that required additional treatment. The authors performed EUS-guided transmural drainage (EUS-TD) for six patients (2.1%) with a pancreatic fistula or dilation of the main pancreatic duct visible by EUS. Percutaneous drainage was provided for 18 patients (6.8%). The success rates for EUS-TD and percutaneous drainage were compared in a retrospective analysis.Results
In all six cases, EUS-TD was performed successfully without complications. Five of the six patients were successfully treated with only one trial of EUS-TD. The final technical success rate was 100% for both EUS-TD and percutaneous drainage. Both the short- and long-term clinical success rates for EUS-TD were 100% and those for percutaneous drainage were 61.1 and 83%, respectively. The differences in these rates were not significant (short-term success, P?=?0.091 vs. long-term success, P?=?0.403). However, the time to clinical success was significantly shorter with EUS-TD (5.8?days) than with percutaneous drainage (30.4?days; P?=?0.0013) in the current series.Conclusions
The EUS-TD approach appears to be a safe and technically feasible alternative to percutaneous drainage and may be considered as first-line therapy for pancreatic fistulas visible by EUS. 相似文献997.
Kim HS Choi CH Lim MC Chang SJ Kim YB Kim MA Kim TJ Park SY Kim BG Song YS Bae DS Kim JW 《Annals of surgical oncology》2012,19(6):1973-1979
Background
To determine the safe criteria for less radical trachelectomy to treat patients with early-stage cervical cancer.Methods
We reviewed medical records and pathologic slides of 65 patients with International Federation of Gynecology and Obstetrics (FIGO) stage IA?CIB1 cervical cancer. The safe criteria for less radical trachelectomy were determined by using three factors such as tumor size ??1?cm, stromal invasion ??5?mm, and no lymphovascular space invasion (LVSI) for minimizing parametrial involvement, lymph node metastasis (LNM), and the need of adjuvant radiotherapy. The diagnostic values were investigated by calculating specificity, negative predictive value for no parametrial involvement, no LNM, and no need of adjuvant radiotherapy.Results
The median age was 32?years (range 22?C44?years), and the median duration of follow-up was 26?months (range 2?C103?months). Among seven single or combined factors for the safe criteria, (1) tumor size ??1?cm, (2) tumor size ??1?cm and stromal invasion ??5?mm, (3) tumor size ??1?cm and no LVSI, (4) tumor size ??1?cm, stromal invasion ??5?mm, and no LVSI did not show parametrial involvement, LNM, and the need of adjuvant radiotherapy. In particular, tumor size ??1?cm showed the highest specificity (28.1?C29.5%) and negative predictive value (100%). In spite of no difference in progression-free survival (PFS) between tumor size ??1?cm and >1?cm (P?=?0.22), tumor size ??1?cm showed better PFS without disease recurrence than tumor size >1?cm (2-year PFS, 100% vs. 90%).Conclusions
Less radical trachelectomy may be safe in patients with early-stage cervical cancer who have tumor size ??1?cm. 相似文献998.
目的:探讨在体内外环境下缺氧诱导因子1α(HIF-1α)过表达对前列腺癌细胞发生上皮间质转化(EMT)并导致肿瘤侵袭能力升高的影响。方法:对已构建的稳定表达HIF-1α的人前列腺癌LNCaP细胞(LN-CaP/HIF-1α)复苏后培养,对HIF-1α过表达进行鉴定。MTT法测定细胞增殖;检测转染前后培养液上清PSA水平;软琼脂成瘤实验比较两种细胞体外成瘤能力;将转染前后的LNCaP细胞注射免疫裸鼠皮下建立皮下肿瘤模型,观察肿瘤生长情况;收集肿瘤标本进一步行免疫组化处理。结果:免疫荧光和Western印迹证实LNCaP/HIF-1α细胞中HIF-1α过表达。同LNCaP细胞相比,转染HIF-1α的人前列腺癌LNCaP细胞培养液中PSA水平明显降低;MTT法显示其更具有增殖活性,体外成瘤能力更强。体内实验显示皮下肿瘤成瘤率提高,成瘤时间提前。肿瘤标本免疫组化提示转染组E钙粘蛋白表达下调,波形蛋白表达上调。结论:HIF-1α过表达能够封闭E钙粘蛋白,上调波形蛋白表达,提示HIF-1α过表达可能通过诱导EMT增强LNCaP细胞侵袭能力。 相似文献
999.
目的 观察DNA甲基转移酶1(DNMT1)和DNA甲基转移酶3b(DNMT3b)基因干扰对胰腺癌BxPC-3细胞增殖和凋亡的影响.方法 利用LipofectamineTM 2000转染DNMT1和DNMT3b小分子干扰RNA (siRNA)至胰腺癌BxPC-3细胞.实验共分5组:DNMT1干扰组(转染DNMT1-siRNA)、DNMT3b干扰组(转染DNMT3b-siRNA)、双重干扰组(转染DNMT1+ DNMT3b-siRNA)、阴性对照组(转染negative-siRNA)和空白对照组(转染脂质体).转染48 h后,应用荧光定量聚合酶链反应(PCR)法和Western blot法分别检测细胞中DNMT1、DNMT3b mRNA和蛋白的表达水平;噻唑蓝(MTT)比色法检测细胞体外增殖活力;流式细胞仪检测细胞凋亡.结果 与空白对照组和阴性对照组比较,各干扰组的DNMT1和(或)DNMT3b mRNA及蛋白表达量均显著降低(P<0.01).DNMTI干扰组和双重干扰组的细胞生长抑制率分别为30.9%和28.3%,均显著高于DNMT3b干扰组的14.5% (P<0.01),而DNMT1干扰组和双重干扰组之间差异无统计学意义(P>0.05).空白对照组、阴性对照组、DNMT1干扰组、DNMT3b干扰组和双重干扰组的细胞凋亡率分别为3.74%、5.07%、44.46%、24.20%和39.24%,各干扰组的细胞凋亡率均比对照组显著增加(P<0.01),DNMT1干扰组与双重干扰组的细胞凋亡率均显著高于DNMT3b干扰组(P<0.01),而DNMT1干扰组与双重干扰组之间差异无统计学意义(P>0.05).结论 DNMT1和(或)DNMT3b基因表达下调后,能抑制胰腺癌BxPC-3细胞生长,并能诱导细胞凋亡.DNMT1单干扰的抑癌作用优于DNMT3b单干扰,DNMT1和DNMT3b双重干扰无明显的协同效应. 相似文献
1000.
【摘要】 目的 通过对强直性脊柱炎(ankylosing spondylitis, AS)僵硬性胸腰段后凸畸形矫形前后影像学参数对比分析及相关性研究,探讨经椎弓根椎体截骨(pedicle subtraction osteotomy,PSO)矫形对矢状面脊柱骨盆序列的影响,进而探究AS后凸患者脊柱骨盆序列的代偿机制。 方法 2004年1月~2010年3月, 38例AS僵硬性胸腰段后凸畸形患者行后路单节段或双节段截骨矫形椎弓根螺钉内固定术。矫形前后拍摄全脊柱侧位X线片,测量AS患者全脊柱后凸角(Cobb T1~S1)、矢状面平衡距离(sagittal vertical axis,SVA)、骨盆入射角(pelvic incidence,PI)、骨盆倾斜角(pelvic tilt,PT)、骶骨倾斜角(sacral slope,SS)及截骨角度(PSO angle)。观察矫形前后影像学参数变化,控制影响患者个体差异的因素,将影像学参数做偏相关分析。 结果 矫形前,Cobb T1~S1=56°±28°,PI=45°±9°,PT=38°±13°,SS=7°±12°,SVA=21 cm±9 cm;矫形后,Cobb T1~S1=11°±22°,PI=46°±9°,PT=21°±10°,SS=24°±9°,SVA=9 cm±5 cm。矫形前,PT、SVA与Cobb T1~S1偏相关系数分别为r=0.81(P<0.01)、0.64(P<0.01);矫形后,PT、SVA与Cobb T1S1偏相关系数分别为r=0.58(P<0.05)、0.72(P<0.01)。PSO angle与Cobb T1~S1、PT偏相关系数分别为r=-0.82(P<0.01)、-0.56(P<0.05),PSO angle与SVA无相关性。 结论 矫形前后,AS患者通过后旋骨盆代偿全脊柱后凸所致的矢状面失平衡;骨盆后旋程度、矢状面平衡距离与全脊柱后凸程度呈正相关;人体自身代偿机制优先恢复骨盆的中立状态而非改善矢状面平衡距离。 相似文献