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121.
122.
Abbas Agaimy Peter H. Wünsch 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2006,391(4):322-329
Background Gastrointestinal stromal tumours (GISTs) are thought to arise from the interstitial cells of Cajal (ICCs). ICCs form a network surrounding the myenteric plexus and between-muscle fibres of the muscularis propria of the tubular GI tract. The cell of origin of so-called extra-gastrointestinal stromal tumours (EGISTs) is not known.Aim and methods To study the diversity of gross presentation of GISTs and to critically assess the incidence of EGISTs and their relationship to mural GISTs, a total of 200 neoplasms with typical morphologic and immunohistochemical features of GISTs were reviewed, looking for any degree of association with the muscularis propria of the gut wall.Results There were 130 gastric (65%), 9 duodenal (4.5%), 48 small intestinal (24%), 9 colorectal (4.5%), 1 appendiceal (0.5%) and 3 unclassifiable GISTs (1.5%). Fourteen cases (7%) were initially submitted as EGISTs (four mesenteric, four omental, one pararectal/prostatic, one pelvic/Douglas, one perivesical, one located between root of mesentery and tail of pancreas, one involving the mesentery, omentum and abdominal wall extensively and one located between liver and stomach). After critical re-evaluation of surgical reports and remote clinical history and a careful search for residual muscular tissue from the gut wall in the tumour pseudocapsule (in some cases supported by desmin immunoreactivity), it was possible to reclassify most of these cases (11/14) as either GISTs with extensive extramural growth resulting in loss of contact to the external muscle coat of the gut (8/14) or as metastases from an inoperable GIST (2/14) or from a previously resected deceptively benign tumour (1/14).Conclusion EGISTs are probably rarer than previously reported (1.5% or less in this study). We concluded that most so-called EGISTs represent apparent EGISTs that should have arisen from the outermost muscle coat, but have lost their contact to the point of origin due to extensive extramural growth pattern. From a surgical point of view, it is crucial to document and mark any focal attachment or adhesions to the gut wall noticed during surgery for an apparent EGIST. In contrast to most other neoplasms, GISTs should be defined by virtue of any degree of association with the muscularis propria (no matter how minimal), but not by localisation of the bulk of the tumour. 相似文献
123.
Anne S Hinckers Manfred Laucht Martin H Schmidt Karl F Mann Gunter Schumann Marc A Schuckit Andreas Heinz 《Neuropsychopharmacology》2006,60(3):282-287
BACKGROUND: A low level of response to alcohol has been associated with both the genetic constitution of the regulatory region (SLC6A4) of the human serotonin (5-hydroxytryptamine, 5-HT) transporter (5-HTT) and with future alcohol intake and an increased risk for alcoholism. To date, all studies of relevant polymorphisms have been carried out in populations in the United States. METHODS: Data were extracted from a subset (n = 243) of a cohort of children who have been observed since birth through evaluation of the family history of alcoholism and psychosocial risk influences. At age 16 years, the response to alcohol was assessed with the Self-Rating of the Effects of Alcohol (SRE) questionnaire, and the average amount of alcohol intake per month was assessed during the prior 6 months. Additional variables that were measured included the 5-HTT genotype, externalizing behavior, and sociodemographic variables, such as gender and age. RESULTS: The level of response to alcohol was significantly lower among carriers of two long alleles of the 5-HTT regulatory region compared with carriers of one or two short alleles (Mann-Whitney U = 5225.0, p = .005). In a multiple regression analysis, the level of response to alcohol and externalizing behavior but not psychosocial factors significantly predicted the average amount of alcohol intake per month. CONCLUSIONS: This study demonstrates that, independent of the assessed psychosocial variables, the 5-HTT genotype correlated with the level of response to alcohol and predicted alcohol intake among 16-year-old adolescents. 相似文献
124.
目的探讨T细胞非特异性活化在CNS脱髓鞘性疾病中的作用。方法分离实验性自身免疫性脑脊髓炎(EAE)易感性BALB/c小鼠外周血单个核细胞(PBMC),采用体外细胞培养方法在体外与碱性髓鞘蛋白(MBP)共培养,测定培养上清液中IFN-γ、NO水平。结果经MBP刺激的PBMC产生IFN-γ[(43.83±6.06)pg/mL]和NO[(180.76±20.75)μmol/L]明显增加,与对照组产生的IFN-γ[(28.52±2.18)pg/mL]和NO[(95.61±13.09)μmol/L]相比差异有统计学意义(P<0.01)。结论在CNS脱髓鞘性疾病发病过程中,活化的T细胞、单核细胞等分泌致炎细胞因子和其他有害物质增多。 相似文献
125.
制作角膜缘干细胞完全缺乏动物模型的新方法 总被引:2,自引:1,他引:1
目的提出一种新的角膜缘干细胞完全缺乏模型制作方法,为干细胞缺乏疾病的治疗性研究提供可靠的模型。方法利用9mm环钻划界,板层切除角膜组织,通过临床评分、印迹细胞学、组织病理及免疫组织化学验证模型的成功。结果板层切除术后30~45d,模型眼角膜混浊、上皮缺损、大量新生血管长入,印迹细胞学可见PAS( )的杯状细胞,组织病理学检查上皮符合结膜细胞表型,免疫荧光染色可见结膜杯状细胞特异性标志MUC5AC阳性表达。结论环钻划界加板层切除法为一种可靠、有效的角膜缘干细胞完全缺乏模型制作方法。 相似文献
126.
The long-term cost of effective management for benign prostatic hyperplasia (BPH) remains an important issue in pharmacoeconomics because about 25% of men aged 50 yr and older experience voiding problems due to BPH. With the ageing population and the increase in the percentage of patients with BPH for whom any type of treatment can be considered, a substantial increase in total costs to society can be expected. The up-front costs of interventional approaches to BPH are being replaced by a pattern of long-term medical and preventive therapy. The age-adjusted rate of transurethral resection of the prostate (TURP) reached a high point in 1987 and TURP rates, but not costs, have been in decline ever since. Mean 1-yr treatment costs (medical therapy and TURP) have been estimated in a pan-European study to be 858 Euros per patient, 75% of which were medication costs. Using a 2-yr time frame for treatment, Medicare costs for finasteride, terazosin, and TURP have been estimated as $3874, $2161, and $1820, respectively. The available models of the total long-term cost for all therapies for BPH remain compromised by a lack of inclusion of indirect costs, the lack of true long-term data and, critically, the lack of human cost information (patient preference). Only medical therapy provides a preventive as well as symptomatic potential and, if all of the issues were fully incorporated, it is likely that medical therapy would be increasingly recognised as economically preferable. 相似文献
127.
目的 观察巯基化合物对内毒素诱导大鼠枯否细胞(KC)NF-kB活性和肿瘤坏死因子-a(TNF-a)释放的影响。方法采用胶原酶灌注和percoll密度梯度离心法分离得到高纯度大鼠KC,在过夜培养后冲洗两遍(不含血清),加入内毒素(LPS)10ng/ml刺激原代培养的KC,观察不同浓度谷胱甘肽乙基酯(GSHEE)及N-乙酰半胱氨酸(NAC)对大鼠KCTNF-a释放和KC内谷胱甘肽(GSH)及NF-kB活性的影响。并观察使用谷胱甘肽合成抑制剂BSO后,对NAC抑制炎症因子的影响,采用凝胶滞留电泳法测NF-kB活性,采用高效液相色谱分析法测GSH水平。结果 LPS诱导KC中GSH水平无变化;GSHEE和NAC可提高KC中GSH水平(P〈0.05),降低NF-kB活性和TNF-a释放(P〈0.05)。NAC与BSO合用时KC中GSH水平无变化,TNF-a释放降低(P〈0.05)。结论 NAC通过抑制KC中NF-kB的激活和TNF-a的释放调节KC功能,但这种抑制作用并非通过增加GSH介导。 相似文献
128.
IIEF-5与NEVA检测在阴茎勃起功能障碍诊断中的意义 总被引:2,自引:2,他引:0
目的探讨应用国际勃起功能评分5(IIEF-5)问卷表结合夜间阴茎勃起测定系统(NEVA)筛选勃起功能障碍(ED)的可行性及意义。方法148例门诊ED病人,应用IIEF-5问卷表评分,再通过NEVA测定仪监测夜间阴茎勃起情况,次日数据输入主机回放并分析。结果93例为心理性ED;在19~69岁的5个年龄组中,重度ED的比例由11.8%到55.0%,NEVA中度异常者IIEF积分(12.98±2.58)分,NEVA重度异常者IIEF积分(7.32±1.04)分。结论NEVA能有效地鉴别心理性与器质性ED,IIEF-5评分值与NEVA检测阴茎勃起时血容量变化值有相关性。IIEF-5与NEVA检测结合,能提高诊断和评估ED的可靠性。 相似文献
129.
C.A. AMEZCUA H.R. MACDONALD† C.A. LUM W. YI‡ L.I. MUDERSPACH† L.D. ROMAN† & J.C. FELIX† 《International journal of gynecological cancer》2006,16(3):1336-1341
In this study, we examine the prevalence of finding isolated tumor cells (ITCs) in negative lymph nodes of endometrial cancer patients using immunohistochemistry. Seventy-six endometrial cancer patients with lymph nodes histologically negative for metastatic disease were examined. Nodal tissue sections were stained with anticytokeratin antibodies AE-1 and CAM 5.2. Nodes with single or groups of cells (two to four cells) < or =0.2 mm and showing cytokeratin reactivity were positive for ITCs. Findings were compared to features of the primary tumor and patient outcome. ITCs were present in 31 of 1712 lymph nodes. Fifteen (19.7%) patients had ITC-positive nodes. ITCs involved only pelvic nodes in nine cases, only para-aortic nodes in five cases, and pelvic and para-aortic in one case. Tumor in adnexa was the only pathologic feature associated with nodal ITCs (P= 0.0485). All 15 patients with nodal ITCs were alive at follow-up. One (6.7%) patient suffered recurrent disease but was alive at last encounter. Disease recurred in 5 (8.8%) of 57 patients without nodal ITCs. Two are alive without disease, two alive with disease, and one died from her cancer. In summary, a significant proportion of endometrial cancer patients have ITCs detected by immunohistochemistry in histologically negative regional lymph nodes. 相似文献
130.
庆大霉素对豚鼠前庭上皮IGF-1及其受体表达的影响 总被引:1,自引:0,他引:1
目的:研究庆大霉素对豚鼠前庭上皮胰岛素样生长因子-1(insulin-like growth factor-1,IGF-1)及其受体(insulin-like growth factor-1 receptor,EGF-1R)表达的影响,并探讨其生物学特性。方法:采用免疫组织细胞化学方法,以抗IGF-1及IGF-1R抗体为标记物,检测庆大霉素损伤后豚鼠前庭上皮自发修复期IGF-1及IGF-1R的表达变化和分布特点;采用Brdu体内标记和抗Brdu抗体免疫组化染色,检测庆大霉素损伤后豚鼠前庭上皮增殖的变化。结果:IGF-1及IGF-1R在正常成年豚鼠前庭上皮细胞中有低水平表达,庆大霉素损伤后,其表达增多。在1d组IGF-1及IGF-1R表达最强,其后逐渐减少。在正常对照组中无Brdu阳性细胞。各实验组均观察到Brdu阳性细胞,7d组最多。结论:庆大霉素损伤后,豚鼠前庭上皮IGF-1及IGF-1R表达增强,其时程变化与细胞增殖活动密切相关。IGF-1在豚鼠前庭上皮损伤后的细胞增殖中可能起重要信号转导作用。 相似文献