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61.

Purpose

Complication rate in reoperative central neck node surgery is one of the main arguments to favor prophylactic central neck dissection at first operation in patients with papillary thyroid carcinoma. We evaluated if reoperative central neck dissection implies an increased postoperative morbidity. Secondarily, we aimed also to verify the effectiveness of the surgical resection of reoperative central neck dissection.

Methods

Forty-one patients who underwent reoperative central neck dissection after initial thyroidectomy for papillary thyroid carcinoma between January 2008 and May 2012 were compared to 41 controls who underwent central neck dissection at initial operation.

Results

The two groups were well matched for age, sex, and pN stage (P?=?0.296, 0.199, and 1.000, respectively). Three patients had distant metastases at presentation. No significant difference was found concerning mean number of removed nodes (P?=?0.064). No significant difference was found between the reoperative and the control groups concerning transient hypocalcemia (17 vs 19, respectively) (P?=?0.901) and transient recurrent nerve palsy (2 vs 2) (P?=?0.608). Follow-up was completed in 69 out of all the included patients (85.2 %). At a mean follow-up of 33 months, two patients (2.9 %) experienced nodal recurrence.

Conclusions

Morbidity of central neck dissection is similar for primary surgery and reoperation. In high-volume centers, reoperative central neck dissection can be safely accomplished when needed, allowing to achieve locoregional control in most of patients.  相似文献   
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Abdominal Radiology - To compare tumor detectability and conspicuity of standard b = 1000 s/mm2 (b1000) versus ultrahigh b = 2000 s/mm2 (b2000)...  相似文献   
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The molecular characterization of the mutations in hemophilia A patients is hampered by the large size of the factor VIII gene and the great heterogeneity of mutations. In this study, we have performed a protocol involving multiplex polymerase chain reaction in which 19 exons were amplified in four different combinations followed by nonradioactive single-strand conformational polymorphism (SSCP) to screen for mutations. Southern blotting was used to detect inversion of the factor VIII gene resulting from recombination between copies of the gene A (F8A) located in intron 22 of the factor VIII gene and two copies close telomeric region of X chromosome. Forty-two hemophilia A patients (21 with severe and 21 with mild-to-moderate disease) were studied. The inversion of factor VIII occurred in 13 of 21 patients affected by severe hemophilia A. One patient showed a large extra band in addition to the three bands observed after Southern blotting with the F8A probe. An abnormal electrophoretic pattern of SSCP was detected in 85% and 50% of the patients affected by mild-to-moderate and severe disease, respectively. Sixteen different mutations were identified. Eleven mutations were novel and comprised 9 point mutations and 2 small deletions. This study shows that the methodology used is safe and rapid and has potential for detecting almost all of the genetic defects of the studied hemophilia A patients.  相似文献   
65.
One of the many biological functions of nitric oxide is the ability to protect cells from oxidative stress. To investigate the potential contribution of low steady state levels of nitric oxide generated by endothelial nitric oxide synthase (eNOS) and the mechanisms of protection against H(2)O(2), spontaneously transformed human ECV304 cells, which normally do not express eNOS, were stably transfected with a green fluorescent-tagged eNOS cDNA. The eNOS-transfected cells were found to be resistant to injury and delayed death following a 2-h exposure to H(2)O(2) (50-150 microM). Inhibition of nitric oxide synthesis abolished the protective effect against H(2)O(2) exposure. The ability of nitric oxide to protect cells depended on the presence of respiring mitochondria as ECV304+eNOS cells with diminished mitochondria respiration (rho(-)) are injured to the same extent as nontransfected ECV304 cells and recovery of mitochondrial respiration restores the ability of nitric oxide to protect against H(2)O(2)-induced death. Nitric oxide also found to have a profound effect in cell metabolism, because ECV304+eNOS cells had lower steady state levels of ATP and higher utilization of glucose via the glycolytic pathway than ECV304 cells. However, the protective effect of nitric oxide against H(2)O(2) exposure is not reproduced in ECV304 cells after treatment with azide and oligomycin suggesting that the dynamic regulation of respiration by nitric oxide represent a critical and unrecognized primary line of defense against oxidative stress.  相似文献   
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Di Lorenzo A  Manes TD  Davalos A  Wright PL  Sessa WC 《Blood》2011,117(7):2284-2295
The reticulon (Rtn) family of proteins are localized primarily to the endoplasmic reticulum (ER) of most cells. The Rtn-4 family, (aka Nogo) consists of 3 splice variants of a common gene called Rtn-4A, Rtn-4B, and Rtn-4C. Recently, we identified the Rtn-4B (Nogo-B) protein in endothelial and smooth muscle cells of the vessel wall, and showed that Nogo-B is a regulator of cell migration in vitro and vascular remodeling and angiogenesis in vivo. However, the role of Nogo-B in inflammation is still largely unknown. In the present study, we use 2 models of inflammation to show that endothelial Nogo-B regulates leukocyte transmigration and intercellular adhesion molecule-1 (ICAM-1)-dependent signaling. Mice lacking Nogo-A/B have a marked reduction in neutrophil and monocyte recruitment to sites of inflammation, while Nogo-A/B(-/-) mice engrafted with wild-type (WT) bone marrow still exhibit impaired inflammation compared with WT mice engrafted with Nogo-A/B(-/-) bone marrow, arguing for a critical role of host Nogo in this response. Using human leukocytes and endothelial cells, we show mechanistically that the silencing of Nogo-B with small interfering RNA (siRNA) impairs the transmigration of neutrophils and reduces ICAM-1-stimulated phosphorylation of vascular endothelial-cell cadherin (VE-cadherin). Our results reveal a novel role of endothelial Nogo-B in basic immune functions and provide a key link in the molecular network governing endothelial-cell regulation of diapedesis.  相似文献   
69.
经肛门内镜显微手术切除直肠肿瘤   总被引:14,自引:3,他引:14  
目的评价经肛门内镜显微手术(TEM)切除直肠绒毛状腺瘤和早期直肠癌的应用效果。方法分析我院总结1995年11月至2001年12月27例TEM手术的临床资料。结果本组患者肿瘤直径中位值2.5cm,肿瘤下缘与齿状线距离(8.9±3.4)cm,肿瘤侵犯直肠周径范围(35.7±17.5)%。平均手术时间(109±46)min。平均住院日4.5d。无围手术期死亡。手术并发症有尿潴留、暂时性大便失禁和慢性阻塞性肺病(COPD)复发。术中2例切穿至腹腔,即刻内镜下修补成功。切缘100%瘤细胞阴性。病理示直肠绒毛状腺瘤14例、直肠腺癌13例,后者包括pTis2例,pT16例和pT25例。直肠癌腔内超声肿瘤T分期符合率为84.6%。5例pT2中2例中转前切除术,1例接受术后放疗,2例无附加任何治疗。平均随访18个月,所有病例无局部复发。死亡2例,但无复发迹象。结论TEM易行且安全,是直肠绒毛状腺瘤和部分T1直肠癌的治愈性手术,也可作为T2直肠癌的姑息性治疗手段。  相似文献   
70.
BACKGROUND:: Gemcitabine is a water-soluble analogue of deoxycytidine whichhas shown significant antitumour activity in a broal panel ofslow-growing murine and human carcinomas. Objective responseshave been reported in early clinical studies in breast, headand neck, non-small cell lung cancer patients. The weekly schedulewas selected for disease-oriented phase II studies because ofits better tolerabil-ity as compared to daily or twice-weeklyschemes. PATIENTS AND METHODS:: Gemcitabine (1000 mg/m2) was given as a 30. min. infusion, weeklyfor three consecutive weeks, followed by one-week rest, every4 weeks. Twenty-nine patients with locally advanced/metastaticgastric cancer and 39 patients with metastatic malignant melanomaentered the study. No prior chemotherapy for advanced diseasehad been given in all cases. RESULTS:: Among 26 evaluable patients with gastric cancer, 1 partial response(PR) of 9 months (4%), 11 no change (NC) and 14 tumour progression(PD) were observed. Of 33 evaluable patients with malignantmelanoma, 1 patient achieved a PR for 10 months (3%), 2 hadNC and 30 PD. Toxicity was similar in the two groups with moderatemyelosuppression, mainly neutropenia, mild to moderate nauseaand vomiting in 70% of patients and fatigue grade 1–2in 50%. CONCLUSIONS:: At the tested schedule gemcitabine has no relevant antitumouractivity in previously untreated patients with advanced malignantmelanoma or gastric cancer. gemcitabine, phase II study, advanced gastric cancer, melanoma  相似文献   
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