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31.
Shiro Oka Shinji Tanaka Iwao Kaneko Hiroyuki Kanao Kazuaki Chayama 《Digestive endoscopy》2007,19(Z1):S30-S33
Endoscopic submucosal dissection (ESD) for colorectal tumors is steadily being developed. Safety and standardization of ESD for colorectal tumors have not been yet established because of the technical difficulties and the unsuitable anatomical characteristics of the colon and rectum. The authors mainly use a Flex knife for mucosal incision and a Hook knife for submucosal dissection to perform ESD safely. Skillful colonoscopic control, selection of scope, distal attachment tip hood, adequate high‐frequency generator and correct approach strategy should all be considered for safe performance of ESD. However, the incidence of indicative lesions is rare because the majority of colorectal tumors are adenomatous large laterally spreading tumors, which can be cured by intentional endoscopic piecemeal resection. At present, ESD for colorectal tumors should be performed only at central facilities that have expert colonoscopists. With the development of new devices and associated techniques, technical standardization of ESD for colorectal tumors is expected in the near future. 相似文献
32.
目的研究房室结逆向传导的电生理特点。方法分析在我院行电生理检查和/或射频消融的成年患者中电生理资料比较完整的300例患者的房室结逆传电生理特点。结果射频消融术后有161例(54%)有房室结逆传。有逆传患者的前传功能要好于无逆传的患者,对于术后存在室房逆传的患者,逆传功能均明显差于前传功能。射频消融术后有28例(17%)经房室结逆传最早激动冠状静脉窦口,其逆传功能较最早激动希氏束电图的病例相比要差,而两者的前传功能差异无统计学意义。结论射频消融术后54%的患者存在房室结逆传,可能是正常人群中室房逆传的真实反映。有室房逆传患者的房室结前传功能优于无室房逆传者,也优于其本身的逆传功能。房室结逆传冲动进入心房可能存在两条不同的通路。 相似文献
33.
目的探讨脊髓血管畸形是否存在血管内皮生长因子(VEGF)表达,及其表达与临床特征之间是否存在相关性。方法在手术中留取56例脊髓血管畸形的脑脊液标本,其中动静脉畸形(SCAVM)23例,硬脊膜动静脉瘘(SDAVF)19例,海绵状血管瘤(CM)14例;以我院12例蛛网膜下腔阻滞病人脑脊液作为对照组,分别通过酶联免疫吸附方法(ELISA)测定脊髓血管畸形脑脊液中VEGF含量。结果SCAVM脑脊液中VEGF浓度为(277±66)pg/ml、SDAVF为(318±54)pg/ml、CM为(146±32)pg/ml均高于正常对照组(123±27)pg/ml。术前栓塞和出血均可导致脑脊液VEGF升高。结论VEGF与脊髓血管畸形的发生、发展存在一定关系,出血和栓塞均可影响VEGF的表达。 相似文献
34.
韩巧云 《实用医学影像杂志》2007,8(2):135-136
目的探讨欧乃影在临床应用中不良反应的发生和预防措施。方法观察2003年10月至2006年7月所作1000例增强扫描者静脉注射欧乃影0.2mL/kg(其量浓度(c)为0.5mol/L)后,不良反应发生的情况。结果1000例患者中,出现不良反应6例,其中,非过敏反应3例,轻度过敏反应3例,无中度及重度过敏反应。结论欧乃影在磁共振增强扫描中不良反应发生率低,临床应用安全。 相似文献
35.
Mana Taweevisit Putchong Isarakul Mookda Chaipipat Kanista Keetacheeva Vannee Wattanasirmkit Shanop Shuangshoti 《Neuropathology》2003,23(4):271-274
Cytokeratin (CK)7 and CK20, the low molecular weight cytokeratins, have been found to have a benefit in the differential diagnosis of some epithelial neoplasms. In the present study, the actual role of these markers in the search of primary tumors in 32 patients with craniospinal metastasis of an unknown primary site at presentation, is evaluated. A series of 36 patients with a known primary tumor were presented for comparison. In the first group, two CK7 and CK20 expression profiles were observed; 87% of metastatic tumors were CK7+/CK20‐ and 13% CK7‐/CK20‐. The lung was the major source (82%) of CK7+/CK20‐ metastatic tumors, whereas it represented only 38% of primary tumor in the second group of a known primary site (P = 0.006). Given the fact that metastatic tumors to the craniospinal axis of an unknown primary site are frequently CK7+/CK20‐, and they have commonly metastasized from the lung, it is doubtful that immunohistochemistry is really helpful. However, CT scan and MRI of the chest still play an important role. Many patients in the present study had to undertake these imaging studies, regardless of the CK7/CK20 result. The immunostains may be useful in cases with other expression profiles, but such examples constituted only a minority in the present study. 相似文献
36.
It has been suggested that reward dependence, as measured by the Tridimensional Personality Questionnaire (TPQ), is related to central noradrenergic activity, a proposition supported by two studies of urinary norepinephrine metabolite. In the current investigation, 190 normal young Han Chinese were examined, with genetic polymorphisms determined for the norepinephrine transporter (1287G/A) and the α2c‐adrenoceptor (Del322–325) to test the association with TPQ personality traits. No significant association was demonstrated for these two polymorphisms and any of the TPQ personality‐factor scores, including reward dependence and its subscales. Our negative findings suggest that the investigated polymorphisms of the norepinephrine transporter and the α2c adrenoceptor do not play a major role in the reward‐dependence personality trait as assessed by TPQ. © 2002 Wiley‐Liss, Inc. 相似文献
37.
Yoshie Ochiai Kazuhiro Kurisu Takashi Kajiwara Hiroshi Kumeda Ryuji Tominaga 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2004,52(2):81-83
We describe a case of type B aortic dissection with large ascending aortic aneurysm occurring 12.8 years after aortic root
replacement (Cabrol procedure) in a non-Marfan patient with cystic medial necrosis of the aorta. We have successfully performed
an extended total aortic arch replacement using a four-branched graft through the “L-indsion” approach (a combination of a
left anterior thoracotomy and upper half median sternotomy). Of note, a histological specimen from the aneurysmal ascending
aortic wall revealed “healed aortic dissection” with fibrous tissue replacing the media and intima in addition to multiple
foci of cystic medial necrosis. 相似文献
38.
以往以乳头为圆心的同心圆剥离法常形成假体的移位,使假体的体表轮廓与前方的自然乳房分离,产生“双重乳房”现象。在研究了女性不同体位下不同的乳房形态及总结了以前的经验后,提出了偏心圆剥离的概念。偏心圆手术设计方法:以乳头为圆心,按其内侧、下侧为直径3/5的比例,以外侧、上侧为直径2/5的比例,形成一偏心圆的剥离范围。偏心圆的直径因考虑到假体的不同形态、大小及底面直径,以经中心假体纵截面的周长的1/2再放大2cm,作为剥离范围的直径。自1991年10月以来已应用了176例,无一术后移位现象,也没有固较多地剥离胸大肌内、下侧止点纤维而影响上肢活动。自然乳房并不是静态的圆锥形或半球形,它具有伸缩的组织学特点,又有随体位变动而变化的特点。用偏心圆法剥离,可使置入的假体与前方的自然乳房融为一体,消除“双重乳房”现象,而成为“真实”的乳房。同时也应积极寻找一种与身体组织相容性好的,弹性、比重与女性乳腺较为一致的,假体容量相对恒定的生物性材料。这样隆乳术才可以更广泛地开展。 相似文献
39.
40.
A New Approach to Percutaneous Subclavian Venipuncture to Avoid Lead Fracture or Central Venous Catheter Occlusion 总被引:5,自引:0,他引:5
JEAN E. MAGNEY DAVID H. STAPLIN DAVID M. FLYNN DAVID W. HUNTER 《Pacing and clinical electrophysiology : PACE》1993,16(11):2133-2142
Pacemaker and defibrillator leads and central venous catheters placed by commonly recommended techniques have been found to pass through the subclavius muscle, the costocaracoid ligament, or the costoclavicular ligament before entering veins medial to the first rib. Entrapment by these soft tissues subjects leads and catheters to stresses imposed by movements of the ipsilateral upper extremity. Accordingly, a new approach has been developed that introduces the lead or catheter into the subciavian vein near the lateral border of the first rib. This placement avoids soft tissue entrapment and may extend the longevity of leads and catheters. 相似文献