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81.
European Archives of Oto-Rhino-Laryngology - Electrical stimulation-supported therapy is an often used modality. However, it still belongs to experimental methods in the human larynx. Data are...  相似文献   
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AIM:To compare the diagnostic yield of heterotopic gastric mucosa(HGM)in the cervical esophagus with conventional imaging(CI)and narrow-band imaging(NBI).METHODS:A prospective study with a total of 760patients receiving a CI examination(mean age 51.6years;47.8%male)and 760 patients undergoing NBI examination(mean age 51.2 years;45.9%male).The size of HGM was classified as small(1-5 mm),medium(6-10 mm),or large(>1 cm).A standardized questionnaire was used to obtain demographic characteristics,social habits,and symptoms likely to be related to cervical esophageal HGM,including throat symptoms(globus sensation,hoarseness,sore throat,and cough)and upper esophageal symptoms(dysphagia and odynophagia)at least 3 mo in duration.The clinicopathological classification of cervical esophageal HGM was performed using the proposal by von Rahden et al.RESULTS:Cervical esophageal HGM was found in 36of 760(4.7%)and 63 of 760(8.3%)patients in the CI and NBI groups,respectively(P=0.007).The NBI mode discovered significantly more small-sized HGM than CI(55%vs 17%;P<0.0001).For the 99 patients with cervical esophageal HGM,biopsies were performed in 56 patients;37(66%)had fundic-type gastric mucosa,and 19 had antral-type mucosa.For the clinicopathological classification,77 patients(78%)were classified as HGMⅠ(asymptomatic carriers);21 as HGMⅡ(symptomatic without morphologic changes);and one as HGMⅢ(symptomatic with morphologic change).No intraepithelial neoplasia or adenocarcinoma was found.CONCLUSION:NBI endoscopy detects more cervical esophageal HGM than CI does.Fundic-type gastric mucosa constitutes the most common histology.One-fifth of patients have throat or dysphagic symptoms.  相似文献   
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Background

Carcinomas arising in the thyroglossal duct cysts are rare, accounting only for about 0.7?C1.5?% of all thyroglossal duct cysts.1 ?C 3 Synchronous occurrence of thyroglossal duct carcinoma and thyroid carcinoma is reported to be even rarer.4 Traditionally, surgical treatments of such coexisting thyroglossal duct cyst carcinoma (TGDCa) and papillary thyroid carcinoma (PTC) were typically performed through a single transverse or double incisions on the overlying skin. A longer, extended cervical incision might be required if neck dissection is necessary. Though this method provides the operator with the optimal surgical view, the detrimental cosmetic effect on the patient of possessing a scar cannot be avoided, despite the effort of the surgeon to camouflage the scar by placing the incision in natural skin creases. Recently, the authors have previously reported the feasibility of robot-assisted neck dissections via a transaxillary and retroauricular (??TARA??) approach or modified face-lift approach in early head and neck cancers.5 , 6 On the basis of the forementioned surgical technique, we demonstrate our novel technique for robot-assisted Sistrunk??s operation via retroauricular approach as well as robot-assisted neck dissection with total thyroidectomy via transaxillary approach.

Methods

This is a case presentation of a 22-year-old woman with synchronous TGDCa and PTC with minimal lymph node metastasis who underwent resection of TGDCa and total thyroidectomy with left neck level III and IV lymph node dissection as well as central compartment lymph node dissection (CCND) via TARA approach with a robotic surgery system after approval from the institutional review board at Severance Hospital, Yonsei University College of Medicine. The incision was just like the TARA approach in head and neck cancer, which has been reported by our institute.6 The operation was proceeded as follows. First, excision of the TGDCa through the retroauricular incision was done followed by total thyroidectomy with CCND via transaxillary approach. Finally, neck dissection of left level III, IV was conducted via transaxillary approach. The da Vinci surgical system (Intuitive Surgical, Sunnyvale, CA) was introduced via retroauricular or transaxillary port. A 30° dual-channel endoscope was used, and the two instrument arms were equipped with 5?mm Maryland forceps and a 5?mm spatula monopolar cautery for TGDCa excision via retroauricular approach. When conducting total thyroidectomy and neck dissection via transaxillary approach, three instrument arms were utilized, each equipped with 5?mm Maryland forceps, ProGrasp forceps and a 5?mm spatula monopolar cautery or Harmonic curved shears. The rest of the surgery was completed with the robotic system (see Video).

Results

The operative procedure was successfully completed utilizing the robotic surgical system with no conversion to open surgery. The operation time for TGDCa excision was 97?min, including the time for skin flap elevation (15?min), setting up the robotic system (5?min), and console time using the robotic system (77?min). Also, the total operation time for the consecutive total thyroidectomy with CCND and level III, IV dissection was 142?min including the time for skin flap elevation (27?min), setting up the robotic system (3?min), and console time using the robotic system (112?min). There were no intraoperative complications. The retroauricular approach for the removal of the TGDCa allowed for an excellent magnified surgical view revealing important structures of the local anatomy. It also created sufficient space for the cutting of the relevant portion of the hyoid bone. Handling of the robotic instruments through the incision was technically feasible and safe without any mutual collisions throughout the operation. The patient??s postoperative parathyroid hormone (PTH) level was within normal range and functions of her both vocal cords were intact. The histopathologic results of the specimens revealed thyroglossal duct cyst with internal papillary carcinoma measuring 1.1?cm with infiltrative tumor margins and papillary microcarcinoma measuring 0.9?cm within the left thyroid lobe with extrathyroidal soft tissue extension. There was no evidence of tumor in the right lobe and the pyramidal lobe of the thyroid gland. As for the lymph nodes resected, 7 out of 9 paratracheal nodes and 2 out of 7 left level III, IV nodes revealed metastatic carcinomas. The patient was discharged on the 8th?day after the operation with no complications. The patient was extremely satisfied with the cosmetic results. The patient has received high-dose radioiodine ablation (RAI) therapy and is currently doing well with no evidence of recurrence.

Discussion

Although there is still a great deal of controversy regarding the treatment of TGDCa, there is little debate that for the cases of synchronous TGDCa and PTC, total thyroidectomy in addition to the Sistrunk procedure must be performed.5 ?C 6,12 As for the patient in our case where left level IV lymph node metastasis was detected under preoperative ultrasonography (USG), if the usual method of surgical procedure was to be selected, double incisions or a single extended transverse incision must be adopted for the Sistrunk??s operation and total thyroidectomy with lateral neck dissection. The conventional method to remove neck masses was to do so by placing an incision on the overlying skin. This ??open?? approach to viewing the lesion has an advantage of providing the operator with the best surgical view, but the recognizable surgical scar that results from the surgery can be displeasing for patients. Therefore the surgeon can try to make a small incision and camouflage the scar by placing the incision in natural skin creases, yet the cosmetic results can still be displeasing for the patient due to its visibility and permanence. This can be an even greater problem if the patient is young and an active member of his/her society and if the lesion is benign or low-grade malignancy which can be simply dissected and excised. Therefore it is the surgeon??s best interest to perform an operation successfully with a ??least obvious?? or ??hidden?? scar whenever possible. Accordingly, we have adopted a novel approach, the transaxillary and retroauricular approach, in view of our increasing surgical experience with various indications such as submandibular gland (SMG) resections and neck dissections in head and neck cancer or thyroid papillary carcinoma.5 ?C 7 Some investigators have demonstrated that robot-assisted neck dissections performed on patients with thyroid cancer and lateral neck node metastasis are feasible and safe.13 We conducted total thyroidectomy with bilateral CCND and level III and IV dissection using the same approach. Although the technical feasibility and safety of neck dissection or SMG resection via retroauricular approach has already been reported previously at our institute, Sistrunk??s operation via retroauricular approach will be challenging. In spite of that, we were able to demonstrate successfully Sistrunk??s operation including the hyoid bone resection through the retroauricular approach. There are however, certain areas of potential difficulties which must be considered with caution during the operation procedure. First, when removing the TGDCa through the retroauricular port, identification of the ipsilateral hyoid bone is primarily important and it is also crucial that dissection along the capsule must be done carefully so as not to rupture the tumor. It is essential that sufficient working space must be created for the comfortable movement of the robotic arms through the retroauricular port and in order to do so, sufficient skin flap elevation in both superior and inferior directions must be performed. It is necessary to elevate the superior skin flap up to the level of the inferior border of the mandible but during this process, the platysma muscle must be identified and meticulous dissection along the subplatysmal plane must be carried out so as not to damage the marginal mandibular branch of the facial nerve. Another area of potential pitfalls concerns the total thyroidectomy with neck dissection through the transaxillary port. Sufficient amount of working space must be secured in order to perform comfortably the contralateral thyroidectomy and neck dissection and in order to do so, skin flap elevation must be done at least 2?cm further based on the ipsilateral omohyoid muscle and the contralateral thyroid gland must be adequately exposed. Using the robotic surgical system in removing the thyroglossal duct cyst, the free movement of wristed instrumentation through the retroauricular incision allowed for efficient dissection and easy handling of the tissue. In this particular case we could not identify the tract beyond the hyoid and up to the foramen cecum, but we anticipate that there would be no technical problems of dissection and excision had it been so. To our knowledge, Sistrunk??s operation and total thyroidectomy with lateral neck dissection via TARA approach utilizing the robotic surgical system has never been attempted before. It has some advantages over the conventional surgery in terms of cosmesis. However, careful consideration in selecting appropriate cases is required and prospective trials should be conducted to recognize long-term outcomes and to overcome potential limitations.  相似文献   
86.
Mice with a targeted mutation of the gastric inhibitory polypeptide (GIP) receptor gene (GIPR) were generated to determine the role of GIP as a mediator of signals from the gut to pancreatic beta cells. GIPR-/- mice have higher blood glucose levels with impaired initial insulin response after oral glucose load. Although blood glucose levels after meal ingestion are not increased by high-fat diet in GIPR+/+ mice because of compensatory higher insulin secretion, they are significantly increased in GIPR-/- mice because of the lack of such enhancement. Accordingly, early insulin secretion mediated by GIP determines glucose tolerance after oral glucose load in vivo, and because GIP plays an important role in the compensatory enhancement of insulin secretion produced by a high insulin demand, a defect in this entero-insular axis may contribute to the pathogenesis of diabetes.  相似文献   
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For the first time, an ultrasonics sonochemistry method is developed to promote the one‐pot hydrosilylation polyaddition polymerization and crosslinking reaction in the preparation of polysiloxane main‐chain liquid‐crystalline elastomers (MC‐LCEs). Due to the extraordinary effect of acoustic cavitation, the polyaddition polymerization and crosslinking reaction can be successfully carried out in an ordinary laboratory ultrasonic cleaner at room temperature, and generates the LCE matrix network in about 30 min. The prepared MC‐LCEs demonstrate good quality, good properties, and stimuli‐actuation performances. Compared to the traditional thermal processing methods for preparing polysiloxane MC‐LCEs, this method exhibits superior properties rapidly, with high convenience and efficiency, and can be a path for batch fabrication at low cost. The work also demonstrates that the ultrasonics sonochemistry method is effective in generating linear main‐chain liquid crystal polymers through hydrosilylation polyaddition and polysiloxane side‐chain LCE matrix through hydrosilylation crosslinking reaction, thus confirming the high availability of ultrasonics sonochemistry in the processes of hydrosilylation polymerization, crosslinking reactions, or synchronous polymerization and crosslinking reactions.  相似文献   
90.
Two new enzyme-linked immunosorbent assays (ELISAs) with chimeric fusion polypeptides for the detection of human antibodies specific to Epstein-Barr virus nuclear antigen 1 (EBNA-1) are described. One is an indirect ELISA with affinity-purified beta-galactosidase-EBNA-1 fusion protein as the antigen. The other is a "sandwich" assay based on the use of anti-beta-galactosidase antibody to capture beta-galactosidase-EBNA-1 fusion proteins in bacterial extracts. A good correlation was shown between antibody titers determined by the ELISA with the EBNA-1 fusion proteins and those determined by a conventional anticomplement immunofluorescence test which is being widely performed with Raji cells for the purpose of research and clinical diagnosis. The advantage of the ELISAs for seroepidemiologic studies on Epstein-Barr virus was demonstrated by sensitive detection of marginal immunoglobulin G antibody to the EBNA-1 domain in serum samples from patients with infectious mononucleosis.  相似文献   
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