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1.
Over the last 40 years, the incidence and prevalence of gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) have continued to increase. Compared to other epithelial neoplasms in the same organ, GEP-NENs exhibit indolent biological behavior, resulting in more chances to undergo surgery. However, the role of surgery in high-grade or advanced GEP-NENs is still controversial. Surgery is associated with survival improvement of well-differentiated high-grade GEP-NENs, whereas poorly differentiated GEP-NENs that may benefit from resection require careful selection based on Ki67 and other tissue biomarkers. Additionally, surgery also plays an important role in locally advanced and metastatic disease. For locally advanced GEP-NENs, isolated major vascular involvement is no longer an absolute contraindication. In the setting of metastatic GEP-NENs, radical intended surgery is recommended for patients with low-grade and resectable metastases. For unresectable metastatic disease, a variety of surgical approaches, including cytoreduction of liver metastasis, liver transplantation, and surgery after neoadjuvant treatment, show survival benefits. Primary tumor resection in GEP-NENs with unresectable metastatic disease is associated with symptom control, prolonged survival, and improved sensitivity toward systemic therapies. Although there is no established neoadjuvant or adjuvant strategy, increasing attention has been given to this emerging research area. Some studies have reported that neoadjuvant therapy effectively reduces tumor burden, improves the effectiveness of subsequent surgery, and decreases surgical complications.  相似文献   
2.
Stellate ganglion (SG) modification has been investigated for arrhythmia treatment. In this study, transesophageal SG imaging and intervention were explored using a homemade 30F integrated focused ultrasonic catheter in healthy mongrel canines in vivo. Anatomic details of SGs were ultrasonically imaged and evaluated. SG had a heterogeneous echoic structure and characteristic profiles sketched by hyper-echoic outlines in an ultrasonogram. Left SGs in the experimental group were successfully ablated through the esophagus under ultrasonic guidance provided by the catheter itself. Two weeks after the ablation, the QT and QTc of the experimental group decreased compared with those of the sham group and at baseline (both p values < 0.001). Histologic examination revealed that left SGs were destroyed. No major complications were observed. This approach may be further explored as a method for ganglia remodeling evaluation and as a strategy of ganglia modification for arrhythmia and for other diseases.  相似文献   
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包含颈外静脉的颈阔肌肌皮瓣修复口腔癌切除后缺损   总被引:1,自引:0,他引:1  
目的探讨将颈外静脉包含在颈阔肌肌皮瓣内修复口腔癌切除后缺损的手术方法。方法先形成蒂在颌缘下包含颈外静脉的颈阔肌肌皮瓣,待口腔肿瘤切除后,将肌皮瓣经口底隧道引入口腔修复缺损。结果临床应用17例,肌皮瓣均无血运障碍,100%存活,其中有2例发生口面痿,经换药后痿口完全闭合。结论将颈外静脉包含在颈阔肌肌皮瓣内有助于肌皮瓣血循环的改善和存活率的提高。  相似文献   
5.
使用赤灵芝的水提取液、乙醇(30%)提取液进行鼠伤寒沙门氏菌回复、小鼠骨髓多染红细胞微核和雄小鼠精子畸变等三种致突变试验。剂量为1000μg.皿^-1和5000μg/皿^-1的鼠伤寒沙门氏菌回复试验的结果为阴性。小鼠在服用7500mg.kg^-1的水提取液或2500mg.kg^-1的醇提取液时,微核试验和精子畸变试验结果均为阴性。  相似文献   
6.
The availabilities of elements in some dust proximal sources of urban pollution were investigated. The sources were: leaded and unleaded automobile exhaust; leaded dry paint; one soil; and mixtures that included the leaded exhaust as a common component. A miniaturized modified Tessier et al. leaching scheme was developed that showed little redistribution of the most available elements. Mn, Pb, S, and Sb were the most readily available in both the leaded and unleaded exhaust; C and Pb in the paint; and Mn and S in the soil. The available elements for the leaded exhaust predominated in its mixtures with evidence of redistributions for the three-component mixture. The environmental pollution (EP) toxicity procedure with five leachings was shown to be approximately equivalent to adding the water-soluble, exchangeable, carbonate, iron/manganese oxide, and part of the organic fractions. Simulated acid rainwater leached elements up to the iron/manganese oxide fraction. The results have application to storm runoff and acid rain leaching of dusts, aerosols, wastes, and soils.  相似文献   
7.
益气化瘀法治疗糖尿病皮肤溃疡38例临床观察   总被引:10,自引:6,他引:4  
糖尿病皮肤溃疡是外科常见病、多发病,因其反复发作,长期不愈,形成顽固性难愈性溃疡,愈后又极易复发,少数尚有癌变可能,所以严重影响了患者的身心健康及生命质量。西医多集中在控制血糖、抗感染、外用生长因子、外科清创术及植皮术等治疗措施上,虽然有一定的疗效,但是却缺乏安全有效加速创面愈合的积极措施。我们采用益气化瘀法为主治疗糖尿病溃疡,可以明显促进与加速创面愈合,减少疤痕形成,提高愈合质量。1993年10月~2002年12月共收治38例糖尿病皮肤溃疡患者,取得了较好的疗效。现报道如下。  相似文献   
8.
PCBs with the highest vapor pressures (fewest chlorines) in Aroclors 1016, 1242, 1254 and 1268 were enriched in the vapor phase relative to the original Aroclor during volatilization from a glass surface for up to 8 hr. PCBs with the lowest vapor pressures (most highly chlorinated) were enriched in the corresponding residue. Thus, visual matching of gas chromatograms with those of Aroclor standards may not be sufficient to identify a specific Aroclor since the past history of a sample is often unknown. The enrichment also was detected using isomeric classes, but not using total chlorine content. The perchlorination method and the Webb-McCall method using all chromatographic peaks agreed quantitatively; this was not always so for the NIOSH multiple peaks and the Webb-McCall methods.  相似文献   
9.
自体造血干细胞移植 (ASCT)是治疗复发性、难治性和侵袭性恶性淋巴瘤的有效方法 ,但因存在体内肿瘤细胞负荷过多和移植物被肿瘤细胞污染 ,使移植后的复发率增高。为了提高ASCT的疗效 ,可采取 :①移植前美罗华体内净化 ,除去外周血B细胞 ,清除移植物的肿瘤细胞污染 ;②移植后用美罗华和非交叉耐药药物交替联合化疗 ,以杀伤体内肿瘤细胞 ;③移植前或后累及野放射治疗 (IFRT)辅助 ,降低原发灶的复发率  相似文献   
10.
目的:探讨莱菔硫烷(sulforaphane,SFN)对氧化低密度脂蛋白(oxidized low-density lipoprotein,ox-LDL)诱导血小板活化的影响及其可能的分子机制。方法:在体外实验中,将健康人纯化血小板与不同浓度的SFN(1.0、2.5、5.0μmol/L)共同孵育40 min,然后用ox-LDL激活血小板20 min,并检测血小板活化的指标,包括CD62P的表达、胞内血小板因子4(platelet factor4,PF4)和趋化因子配体5(chemokine ligand 5,CCL5)的释放水平。机制上,用Western blot蛋白免疫印迹法检测血小板肉瘤酪氨酸激酶(sarcoma tyrosine kinase,Src)及其下游的脾酪氨酸激酶(spleen tyrosine kinase,Syk)磷酸化水平;用活性氧(reactive oxygen species,ROS)检测试剂盒测定胞内总ROS水平。结果:ox-LDL诱导的血小板CD62P的表达以及PF4和CCL5的释放水平均可被SFN显著抑制(P <0.05);SFN显著下调ox-LD...  相似文献   
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