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61.
This study compares the incidence of local tumor recurrence following primary excision with the CO2 laser, Nd:YAG laser (contact), Argon Beam Coagulator, or electrocautery. One hundred eight Fisher 344 rats with R3230AC mammary tumors (1.6 +/- 0.04 [SD] cm diameter) were used. All animals were randomized into groups of similar tumor size. In groups C and CS, excision was performed with a Sharplan 1060 CO2 laser (TEMoo, 25 W, continuous wave [CW], 0.2-mm spot size). Wounds in group CS were "sterilized" (0.5-mm spot size, 25 W, CW) by gently heating the wound without causing blanching or charring. In group N, a 0.4-mm contact Laser Blade and a Cooper 8000 Nd:YAG laser at 20 W CW was used. In groups SA1 and SA2, tumors were excised with the scalpel, and hemostasis and wound "sterilization" were accomplished with the Bard System 6000 Argon Beam Coagulator (ABC) at 40 W and 4 liters/min argon gas flow in SA1 and 12 liters/min in SA2. In group E, excision was accomplished at 40 W blend mode, 10 W spray mode. In group EA, excision was accomplished at 60 W cutting current, and hemostasis was achieved with the ABC. The animals were examined for evidence of recurrence for 34 days postoperatively. Mortalities were excluded from analysis. The incidence of recurrence was 11/14 (79%) in C, 6/16 (38%) in CS, 10/14 (71%) in SA1, 6/13 (46%) in SA2, 6/15 (40%) in N, 7/10 (70%) in EA, and 3/15 (20%) in E. Group E is statistically different (P less than .01) from groups EA, C, and SA1. Group C was different (P less than .01) from groups E, CS, and N. These results demonstrate an inverse relationship between tumor recurrence and local thermal effects at the surgical site. The ABC did not increase tumor recurrence. Contact YAG surgery was similar to CO2 laser excision and "sterilization." An attempt to study the influence of gas flow and pressure on local tumor recurrence and metastases should be made.  相似文献   
62.
目的 探讨分析基于心脏磁共振特征追踪技术(FT-CMR)的心脏功能评估参数对心房颤动冷冻球囊消融患者治疗后复发的预测效能。方法 选取2019年6月至2020年12月收治的126例预行冷冻球囊消融术的心房颤动患者为研究对象,术前均进行心脏磁共振检查,根据术后6个月内患者有无复发将其分为窦性心律组72例和房颤复发组54例。比较两组患者左心房应变及应变率参数,采用FT-CMR评估患者心脏功能,并进行单因素、多因素logistic回归分析,探讨FT-CMR心脏功能评估参数对心房颤动冷冻球囊消融术后复发的预测价值。结果 房颤复发组患者女性、高血压、糖尿病、非阵发性心房颤动比例显著高于窦性心律组(P<0.05)。房颤复发组患者左心房总应变(Es)、左心房正向应变率峰值(SRs)、左心房被动应变(Ee)、心室舒张早期负向应变率峰值(SRe)、左心房整体纵向应变(PLAS)参数值低于窦性心律组(P<0.05)。Logistic多因素回归分析结果显示,性别(OR=3.511,95%CI:1.036~11.906)、PLAS(OR=1.089,95%CI:1.039~1.141)是心房颤动冷冻...  相似文献   
63.
目的 研究血清甲状腺球蛋白(Tg)、甲状腺球蛋白抗体(TgAb)对甲状腺癌根治术联合131I治疗后随访期间复发/转移的评估价值。方法 回顾性分析2018年6月—2020年6月中国贵航集团三〇二医院收治的106例分化型甲状腺癌患者的临床资料,患者均接受甲状腺癌根治术治疗,术后均采用131I进行清除残留的甲状腺组织(清甲)治疗。随访24个月,将患者分为复发转移组(21例)和未复发转移组(85例)。比较两组临床资料、131I治疗情况及血清促甲状腺激素(TSH)、Tg、TgAb。绘制受试者工作特征(ROC)曲线分析血清Tg、TgAb检测对甲状腺癌根治术联合131I治疗后复发/转移的预测价值。采取非条件一般Logistic回归模型进行多因素分析。结果 与未复发转移组比较,复发转移组原位肿瘤T4分期、手术方式为腺叶切除或近全切、残余甲状腺质量≥1 g、手术至131I治疗时间> 3个月、24 h摄131I率≤ 20%患者的占比均较高(P <0.05);复发转移组血清Tg和TgAb水平均较高(P <0.05);ROC曲线分析结果显示:血清Tg预测甲状腺癌根治术联合131I治疗后复发或转移的最佳截断值为1.674 μg/L,AUC为0.803(95% CI:0.721,0.884),敏感性为81.1%(95% CI:0.724,0.898),特异性为63.8%(95% CI:0.585,0.691);血清TgAb预测的最佳截断值为44.19 3 IU/mL,AUC为0.911(95% CI:0.859,0.963),敏感性为89.2%(95% CI:0.813,0.971),特异性为72.5%(95% CI:0.674,0.774)。非条件Logistic一般回归分析结果显示:原位肿瘤T4分期[O^R=2.916(95% CI:1.325,6.417)]、腺叶切除或近全切[O^R=3.243(95% CI:2.174,4.838)]、残余甲状腺质量≥ 10 g[O^R=1.835(95% CI:1.514,2.224)]、手术至131I治疗时间> 3个月[O^R=1.962(95% CI:1.371,2.808)]、24 h摄131I率≤ 20%[O^R=2.638(95% CI:1.219,5.709)]、血清Tg ≥ 1.674 μg/L[O^R=2.503(95% CI:1.430,4.360)]、血清TgAb≥ 44.193 IU/mL[O^R=2.944(95% CI:2.016,4.299)]可能是甲状腺癌根治术联合131I治疗后复发或转移的危险因素(P <0.05);风险因素预测模型预测甲状腺癌根治术联合131I治疗后复发/转移的ROC曲线下面积为0.961(95% CI:0.935,0.987),标准误为0.010,临界值为73.162,敏感性为91.9%(95% CI:0.863,0.957),特异性为88.2%(95% CI:0.845,0.922)。结论 甲状腺癌根治术联合131I治疗后出现复发/转移的患者血清Tg、TgAb水平明显升高,Tg、TgAb对预测复发/转移具有较好的价值,联合其他危险因素建立风险因素预测模型可进一步提高预测价值。  相似文献   
64.
Local recurrence is a serious complication of breast carcinoma that reduces quality of life and influences prognosis. The aim of this study was to determine whether local recurrences of breast carcinoma are genetically related to the primary tumours. Forty cases of locally recurrent breast carcinomas (median onset: 3.6 years after primary surgery) were analysed: 22 patients had undergone breast-conserving therapy and 18 mastectomy. Eighteen microsatellites on chromosomes 2p, 3p, 5q, 10q, 11p, 11q, 13q, 17q, 17p, 18p were amplified by PCR using fluorescent-labelled primers, automatically detected after polyacrylamide gel electrophoresis and analysed for loss of heterozygosity (LOH) or microsatellite instability (MSI). Follow-up data were available for 39 cases with a median value of 89 months. All LOH and MSI found in the primary tumours were also present in the corresponding recurrences, indicating that they are genetically related to the primary tumours and not secondary malignancies in the same breast. MSI was found in three cases, of which one harboured MSI at more than two loci. The median value of LOH per case was significantly higher in the recurrent (four per case) compared to the primary tumours (two per case; p < 0.001, Mann-Whitney test), reflecting the genotype of tumour progression. Early local recurrence was associated with specific LOH for TP53.15 (p = 0.018, log-rank test) in the primary tumours. LOH on D13S1699 or D17S855 was associated with lymph node metastases (p = 0.024 and p = 0.019, respectively; chi-square test). In addition, tumour grade, lack of oestrogen or progesterone receptor expression, young patient age and early appearance of local recurrence significantly correlated with poor survival. The development of local recurrence despite clear resection margins may result from residual DCIS distant from the invasive carcinoma, homing of circulating tumour cells, or genetically altered, histologically normal breast tissue not immediately adjacent to the invasive carcinoma.  相似文献   
65.
Clinical recurrences of Herpes simplex virus type 1 (HSV-1)-associated genital herpes are thought to be caused by reactivation of latent endogenous HSV-1. However, the possibility of reinfection with exogenous HSV-1 cannot be excluded. This study aimed to determine the incidence of genital HSV-1 superinfection in patients by investigating the genotype of sequential HSV-1 isolates obtained from the same anatomical site of patients with clinical recurrences of genital HSV-1 recurrent genital herpes. Sequential genital HSV-1 isolates were genotyped by PCR amplification of the hypervariable regions located within the HSV-1 genes US1 and US12. Whereas the sequential HSV-1 isolates in 11 of the 13 patients studied had the same genotypes, the sequential isolates of 2 patients showed a different genotype. The data suggest that HSV-1-induced recurrent genital herpes can be associated with genital reinfection with an exogenous HSV-1 strain.  相似文献   
66.
Data on the occurrence of neural tube defects in first-, second-, and third-degree relatives of probands were collected in a United States study. The proportions of affected individuals were 3.2%, 0.5%, and 0.17% respectively. These findings are compared to those from other recent North American studies, and differences are discussed. It is pointed out that accurate recurrence risk figures may not be available, and that caution should be used when counseling families with relatives who are affected with NTD.  相似文献   
67.
Studies from the last decade on factors influencing reproductive planning after genetic counselling were reviewed. Increased possibilities of DNA-analysis and prenatal diagnosis might have brought about a shift in the paramountcy of factors influencing reproductive planning after genetic counselling. In contrast to the literature in the seventies, the magnitude of the genetic risk was no longer found to be one of the decisive factors in postcounselling reproductive planning. Instead, the interpretation of the risk as high or low and the desire to have children appeared to be paramount. The impact of new developments in DNA-analysis in prenatal diagnosis and presymptomatic testing will be an important subject for future studies on factors influencing reproductive planning.  相似文献   
68.
In order to determine if patients with a history of previous urothelial cell carcinoma (UCC) but with current normal urinary cytology have DNA damage in urothelial cells, the single-cell gel electrophoresis (comet) assay was conducted with cells obtained by urinary bladder washings from 44 patients (28 with a history of previous UCC). Increased DNA damage was observed in cytologically "normal" urothelial cells of patients with a history of UCC when compared with referents with no similar history and after correcting the data for smoking status and age (P < 0.018). Increased DNA damage also correlated with the highest tumor grade, irrespective of time or course of the disease after clinical intervention (Kendall tau correlation, 0.37, P = 0.016). Moreover, aneuploidy, as assessed by DNA content ratio (DCR; 75th/25th percentile of total DNA fluorescence of 50 comets/patient) was unaltered by smoking status, but increased with UCC grade: 1.39 +/- 0.12 (median +/- 95% confidence interval; referents); 1.43 +/- 0.11 (Grade I UCC; P = 0.264, against referents); 1.49 +/- 0.16 (Grade II UCC; P = 0.057); 1.57 +/- 0.16 (Grade III UCC; P = 0.003). Micronucleated urothelial cells (MNC) were also scored on Giemsa-stained routine cytological smears and were found not to correlate with DNA damage or DCR. MNC frequencies were higher for patients with a history of UCC and/or smoking than referents with neither history, but there was no statistical difference between groups. Taken together, these results suggest that the normal-appearing urothelium of patients resected for UCC still harbor genetically unstable cells.  相似文献   
69.
BACKGROUND: Results of conservative management of epithelial ovarian cancer (EOC) remain controversial in the literature. The aim of this study was to assess the clinical outcomes and fertility following fertility-sparing surgical management of EOC in a retrospective multicentre study. METHODS: A multicentre retrospective study was performed by members of two French groups. Six inclusion criteria were defined: (i) Histological review by the same pathologist; (ii) age < or =40 years; (iii) conservative management; (iv) complete peritoneal staging; (v) delivery of a platinum-based chemotherapy in stage > or = IC; and (vi) follow-up >1 year. RESULTS: Thirty-four patients fulfilled the inclusion criteria: 30 had stage IA disease; three had stage IC and one had stage IIA. Eleven patients had recurrence: 10 patients had invasive disease and one had borderline recurrence. Among 10 patients with invasive recurrence, initial stage and grade were: stage IA G1, n = 1; stage IA G2, n = 4; stage IA G3, n = 1; and stage> or = IC, n = 4. All patients with stage > IA had recurrence. Ten pregnancies were observed in nine patients. CONCLUSION: Conservative surgery for patients with EOC could be considered in young patients with stage IA G1 disease. This procedure should not be performed in patients with FIGO stage > IA.  相似文献   
70.
ABSTRACT

Purpose: Investigate the content of fibrotic fibrils in gingival tissue and the proliferation of fibroblasts collected from recurrent and non-recurrent hereditary gingival fibromatosis (HGF) and idiopathic gingival fibromatosis (IGF).

Methods: Gingival biopsies were collected from HGF (n = 3) and IGF (n = 3) donors with recurrent and non-recurrent gingival overgrowths and from a control group (Ctrl, n = 3). Hematoxylin staining was performed to evaluate the histomorphology of gingival tissue. Heidenhain’s AZAN trichrome staining served for visualization of fibrotic fibrils in gingiva. Quantitative analysis of the content of fibrotic fibrils in gingival tissue was performed using a polarized light microscope. Proliferation was evaluated at 24 h, 48 h, and 72 h in fibroblast cultures using a cell proliferation ELISA assay based on 5-bromo-2?-deoxyuridine (BrdU).

Results: Numerous blood vessels and fibroblasts were observed in recurrent overgrowths, whereas moderate blood vessels and moderate to scanty fibroblasts were detected in non-recurrent overgrowths. Heidenhain’s staining revealed numerous collagen fibers in both recurrent and non-recurrent overgrowths. Quantitative analysis in a polarizing microscope showed significant accumulation of fibrotic fibrils exclusively in the overgrowths with the recurrence. In all time-points, increased proliferation of cells from all recurrent overgrowths was observed, but not from overgrowths which do not reoccur.

Conclusions: The study revealed that recurrent gingival overgrowths consist of highly fibrotic and dense connective tissue with numerous blood vessels and abundant fibroblasts. We also demonstrated that unlike fibroblasts derived from overgrowths, which did not present recurrence, fibroblasts derived from highly fibrotic and recurrent overgrowths maintain high rate of proliferation in vitro.  相似文献   
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