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61.
Hwang Choi 《Digestive endoscopy》2006,18(1):1-3
Endoscopic technologies have been developed greatly. As for early gastric cancer, the indications for endoscopic mucosal resection for early colorectal cancer have been widened recently. Technological advances can support wider and deeper resections using endoscopy but the remaining problem for the endoscopic management of cancer is lymph node metastasis. I discuss here the indication for endoscopic mucosal resection for early colorectal cancer to bring into focus the risk factors for metastasis to lymph nodes. 相似文献
62.
Rate-Related and Autonomic Effects on Atrioventricular Conduction Assessed Through Beat-to-Beat PR Interval and Cycle Length Variability 总被引:1,自引:0,他引:1
CHRISTOPHER T. LEFFLER M.D. J. PHILIP SAUL M.D. RICHARD J. COHEN M.D. Ph .D. 《Journal of cardiovascular electrophysiology》1994,5(1):2-15
Atrioventricular Conduction Variability. Introduction: Atrioventricular AV) conduction time varies on a beat-by-beat basis in response to the influences of cardiac efferent autonomic activity and rate-dependent electrical recovery processes. The goals of this study were to distinguish these effects on AV conduction time and to compare the variability in sinoatrial and AV nodal function. Methods and Results: The PR interval on the surface ECG served as an index of AV conduction time in this study of 14 adult human subjects undergoing a random interval breathing protocol. P and R waves were located by a template-matching algorithm. Spectral analysis allowed frequency-domain comparisons between PR and RR interval variability. Spectra of PR and RR intervals had similar power distributions, although the power of the RR interval spectra was much greater. Autonomic blockade with atropine plus propranolol reduced the power of both spectra. Standing significantly decreased the spectral power from 0.15 to 0.5 Hz for PR and RR spectra, and introduced a peak near 0.1 Hz in the mean PR and RR spectra, although the latter finding was significant only for the RR interval spectra. Propranolol had no significant effects on the PR and RR interval spectra. Linear regression analysis allowed quantification of the autonomic and recovery effects on AV conduction and showed which effect predominated. Simple linear regression confirmed in adults a previous finding in children that conduction time may be either positively or negatively correlated with cycle length. By multiple regression and transfer function analysis, the inverse relation seen in some subjects was attributed to the effect of recovery from the preceding cycle. With the preceding recovery period accounted for, the conduction time and cycle length of the current beat were positively correlated, presumably due to the parallel autonomic effects on the sinoatrial and AV nodes. The magnitude of the recovery effect predicted by the regression analysis was similar to published values. Conclusion: A noninvasive evaluation of the surface ECG can be used to compare variability in AV conduction time and cycle length and characterize the effects of autonomic efferent activity and rate-related recovery on AV nodal function. 相似文献
63.
The effects of zymosan-activated plasma(ZAP)on lung fluid exchangeand on superoxide anion production by granulocytes were studied in 8 consciousgoats with chronic lung lymph fistula,It was found that after ZAP infusion, thecirculating granulocytes were activated and the release of superoxide anions wasmarkedly enhanced. There was an increase in lung lymph flow and proteinconcentration.It suggests that the superoxide anion released by the stimulatedgranulocytes can play a role in inducing lung injury by the activated complement. 相似文献
64.
Y. Kannan R. H. Stead C. H. Goldsmith J. Bienenstock 《Journal of neuroscience research》1994,37(3):374-383
Induction of neurite outgrowth from superior cervical ganglia (SCG) by rat lymphoid tissues was studied using a tissue culture model. Neonatal rat SCG were cultured with 6–12-week-old rat thymus, spleen, or mesenteric lymph node (MLN) explants in a Martrigel layer, in defined culture medium without exogenous nerve growth factor (NGF). SCG were also co-cultured with neonatal rat heart (as positive control) or spinal cord (SC; as negative control). To determine whether inflammation affects the ability of lymphoid tissues to induce neurite outgrowth, we also examined MLN at various times after infecting rats with Nippostrongylus brasiliensis (Nb-MLN). In one series of experiments, a single lymphoid tissue explant was surrounded by four SCG at a distance of 1 mm. The extent of neurite outgrowth was determinded by counting the number of neurites 0.5 mm away from each ganglion at several time points. Adult thymus and, to a lesser extent, spleen had strong stimulatory effects on neurite outgrowth from SCG after 12 hr or more in culture. For thymus tissue, this was similar to the positive control heart explants. MLN from normal rats had minimal effect on neurite outgrowth; however, Nb-MLN showed a time-dependent enhancement of the neurite outgrowth, maximal at 3 weeks after infection. The relative efficacy of neurite outgrowth induction (heart ≥ thymus ≥ Nb-MLN ≥ spleen ≥ MLN ≥ SC) was confirmed in a second series of experiments where one SCG was surrounded by three different tissue explants. We then examined the role of 2.5S NGF, a well-known trophic factor for sympathetic nerves, in the lymphoid tissue-induced neurite outgrowth. Anti-NGF treatment of co-cultures of SCG and heart almost completely blocked the neurite outgrowth. Anti-NGF also significantly inhibited thymus- and spleen-induced neurite outgrowth, but not as effectively as heart-induced neuritogenesis (93,80, and 77% inhibition at 24 hr; 86,70, and 68% inhibition at 48 hr for heart, thymus, and spleen, respectively). On the other hand, anti-NGF inhibited only 8% of neurite outgrowth induced by 3-week post-infection Nb-MLN at 24 hr, and 41% at 48 hr. These data show that several adult rat lymphoid tissues exert neurotrophic/tropic effects. The predominant growth factor in thymus and spleen is NGF, while Nb-MLN produces factor(s) which is (are) immunologically distinguishable from NGF. These neurotrophic/tropic factors are produced during the reactive lymphoid hyperplasia that forms part of the inflammatory response against the nematode, N. brasiliensis. This suggests the possibility that cytokines produced by lymphocytes or other inflammatory cells may stimulate sympathetic neurite outgrowth in vivo. © 1994 Wiley-Liss, Inc. 相似文献
65.
D. A. Basketter E. W. Scholes M. Cumberbatch C. D. Evans I. Kimber 《Contact dermatitis》1992,27(4):209-213
The guinea pig maximization test (GPMT) has proven to be a valuable tool for the identification of the skin sensitization potential of chemicals. The method identifies a hazard which can lead in the EC to compulsory labelling of that chemical. In the present study, data on sulphanilic acid derived from the GPMT has been compared with results from a second guinea pig assay (the cumulative contact enhancement test) and the murine local lymph node assay, both of which require only topical application of chemical. Except for the GPMT, no test identified any sensitizing activity associated with exposure to sulphanilic acid. These latter results are consistent with the experience gained from substantial human exposure in an occupational setting and from which no cases of allergic contact dermatitis to sulphanilic acid have arisen over a 20-year period. In consequence, it is questioned which test protocol in practice has given the more accurate identification of sensitization hazard relevant to man. 相似文献
66.
Hiroshi Terasawa M.D. Kazuhisa Uchiyama M.D. Masaji Tani M.D. Manabu Kawai M.D. Takeshi Tsuji M.D. Katsuyoshi Tabuse M.D. Yasuhito Kobayashi M.D. Katsutoshi Taniguchi M.D. Hiroki Yamaue M.D. 《Journal of gastrointestinal surgery》2006,10(6):823-828
To determine the prognostic factors for patients with pathological T1 (pT1) carcinoma of the ampulla of Vater, 36 consecutive
patients with carcinoma of the ampulla of Vater who underwent surgery were retrospectively analyzed in terms of clinicopathological
features. The overall 5-year Kaplan-Meier survival in all patients was 50.2%, and the median survival of all patients was
64.0 months. Factors favorably influencing a long-term outcome were the absence of lymph node metastasis (P<0.0001), the absence of ulcer formation of the tumor (P=0.0062), and the absence of tumor invasion into the duodenum (P = 0.0025) and the pancreas (P=0.0098). In a multivariate analysis, lymph node metastasis was the only predictor of survival (P=0.0023). In the pT1 stage patients, 20% of the patients had lymph node metastasis, and their survival was statistically poor
compared to the pT1 patients without lymph node metastasis (P=0.017). As for survival after the operation, there was no significant difference between pancreatoduodenectomy and pylorus-preserving
pancreatoduodenectomy. 相似文献
67.
本文报道11例正常健康对象,经食道心房调搏法观察可乐定对窦房结和房室结的影响。结果表明,可乐定具有抑制窦房结和房室结的作用,心得安有协同作用,阿托品能逆转可乐定的作用,对房室传导阻滞和病态窦房结综合征患者,合用可乐定与心得安时宜慎重。 相似文献
68.
阈下刺激定位慢径消融靶点的临床应用研究 总被引:1,自引:0,他引:1
目的 :探讨利用阈下刺激 (STS)定位房室结折返性心动过速 (AVNRT)的慢径消融靶点的临床应用价值。方法 :选择AVNRT患者 6例 ,经常规电生理检查明确诊断后 ,将大头电极放在冠状窦口下缘与希氏束之间的中下区域进行标测 ,测定该点的起搏阈值后 ,诱发AVNRT ,然后发放STS终止AVNRT ,在终止位点处试消融 ,观察STS标测消融的有效性 ;在非终止位点处 ,结合局部心内电图判断是否进行试消融 ,如在非终止位点处试消融 ,观察STS标测的可靠性。同时观察STS标测定位的安全性。结果 :在 6例患者中 ,有 3例STS终止了持续性AVNRT ,且在终止位点处试消融并获得成功 ;有 5例共在 10个位点处发放了STS ,其中在 9个位点未终止心动过速 ,在这些非终止位点处试消融均未获得成功 ,非 1个位点出现了心房夺获。所有患者在STS标测过程中 ,未出现心房颤动、心动过速的加速或心室颤动等现象。结论 :STS终止AVNRT的位点是判断消融靶点的一个良好的电生理学指标。STS标测定位是安全、有效和可靠的一种方法 ,值得进一步地深入研究 相似文献
69.
MASAHIKO NAKASONO MITSUYOSHI HIROKAWA NAOKI MUGURUMA SEISUKE OKAMURA SUSUMU ITO AKIKO IGA SATOSHI WADA MICHIYO OKAZAKI TAKAHIRO HORIE TAMOTSU FUKUDA TOSHIAKI SANO 《Journal of gastroenterology and hepatology》2006,21(1):65-70
Background: Colonic pseudolipomatosis is rare and the pathogenesis is controversial. The purpose of the present paper was to clarify endoscopic and histological characteristics of colonic pseudolipomatosis and to discuss the etiology. Methods: A total of 15 lesions from 14 patients was reviewed. They were able to be histologically classified into two groups on the basis of variety in size of the vacuoles: Group A, the ratio of largest vacuole to smallest vacuole in size is less than three, Group B, the ratio is more than four. Results: Four of 15 lesions were group A, and were endoscopically polypoid or flat lesions covered with normal‐looking mucosa. They were microscopically characterized by (i) predominant location in the upper portion of the lamina propria; (ii) no submucosal involvement; (iii) less variation in vacuolar size; and (iv) no association with lymph follicles. The vacuoles of group A contained proteinaceous materials in two of four lesions. Group B (11 lesions) had small elevated mucosa with normal‐looking surface or non‐elevated reddish mucosa. Microscopically, the lesions were mainly located in the lower portion of the lamina propria, occasionally also in the submucosa, had variable‐sized vacuoles, and were related to lymph follicles. Conclusion: It is suggested that the vacuoles in group A contain fluid, and may indicate an abnormal stagnation of interstitial fluid. Microscopic appearance of group B is essentially similar to that of pneumatosis coli. It is thought that group B probably results from penetration of gas from the crypts into the mucosa during colonoscopy. It is unclear why group B had a preference for ileocecal valve and an association with lymph follicles. 相似文献
70.
目的 了解早、中期胃癌的临床、胃镜和病理学特征。方法 回顾性分析我院 11年中经外科手术和病理诊断的 75例早、中期胃癌患者的临床、胃镜、外科手术和病理等方面资料。结果 早、中期胃癌临床表现无特征性 ,男女之比为 2 .41∶1,以 61~ 70岁最多 ,胃窦是其好发部位 ,病理组织学以管状腺癌为多 ,胃镜误诊率是 12 .86%,淋巴转移率是 2 5 .3 3 %。结论 早、中期胃癌有明显的好发年龄和好发部位 ,以管状腺癌为多 ,胃镜误诊的主要原因是不能鉴别病变的良、恶性和准确判断病变量 ,影响淋巴转移的因素是浸润深度、广度、肿瘤大小和年龄 ,而与性别、组织学的分化程度无明显关系。 相似文献