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21.
This report describes transoesophageal echocardiographic (TEE) monitoring in a one-year-old boy undergoing patent ductus arteriosus (PDA) interruption. After application of a first vascular clip, echocardiographic monitoring detected incomplete interruption of ductal flow, prompting the surgeon to add a second clip to the ductus. The procedure was performed via a new surgical technique: video-assisted thoracoscopic surgery (VATS). This innovative approach offers many advantages to patient care including reduced postoperative pain and better preservation of pulmonary function. We conclude that the use of TEE monitoring during PDA interruption via the VATS procedure may improve the surgical result, and eliminate reintervention and the complications associated with residual ductal flow.  相似文献   
22.
BACKGROUND: This study was designed to determine whether Helicobacter pylori forms part of the normal microenvironment of the appendix, whether it plays a role in the pathogenesis of acute appendicitis, and whether it is associated with increased expression of inducible nitric oxide synthetase (iNOS) in appendicular macrophages. METHODS: Serology for H. pylori was performed on 51 consecutive patients undergoing emergency appendicectomy. Appendix samples were tested for urease activity, cultured and stained for H. pylori, graded according to the degree of inflammatory infiltrate, and probed immunohistochemically for iNOS expression. RESULTS: The mean age of the patients was 21 (range 7-51) years. Seventeen patients (33 per cent) were seropositive for H. pylori but no evidence of H. pylori was found in any appendix specimen. However, an enhanced inflammatory cell infiltration was observed in seropositive patients (P < 0.04) and the expression of macrophage iNOS in the mucosa of normal and inflamed appendix specimens was increased (P < 0.01). CONCLUSION: H. pylori does not colonize the appendix and is unlikely to be a pathogenic stimulus for appendicitis. Priming effects on mucosal immunology downstream from the foregut may occur after infection with H. pylori.  相似文献   
23.
Plasminogen activator (PA) expression plays an important role in smooth muscle cell (SMC) migration and may therefore contribute to mechanical force-induced arterialization of vein grafts. The aim of this study was to determine whether pulse pressure due to pulsatile flow modulates SMC migration via urokinase (u-PA)-dependent mechanisms. Using a perfused transcapillary culture system, human umbilical vein SMC were exposed to pulse pressures (0-56 mmHg), in the absence or presence of human umbilical vein endothelial cells (EC) by varying pulsatile flow rates (0 ml/min to 25 ml/min). SMC cultured in the absence of EC increased their migration following exposure to increased pulse pressure (248+/-14%). Both u-PA and matrix metallo-proteinase 1 (MMP-1) expression was significantly elevated in SMC exposed to pressure as compared to static controls. The role of proteases in the pulse pressure-induced enhancement of SMC migration was confirmed following pretreatment with aprotinin, an anti u-PA antibody and metalloproteinase inhibitors (181+/-14% for aprotinin vs. 256+/-25% for control, 108+/-4% for anti-u-PA antibody vs. 233+/-17% for non-immune IgG, and 114+/-9% for BB-94, 105+/-7% for BB-3103 vs. 222+/-5% for control). Using SMC derived from u-PA gene knock-out mice, the SMC migratory response to increased pulse pressure was completely inhibited despite a significant increase in MMP expression in these cells. These results suggest that pulse pressure due to pulsatile flow induces SMC migration in vitro via u-PA and MMP-dependent mechanisms. Moreover, u-PA gene deletion results in blunting of pressure-induced SMC migration despite the endogenous upregulation of metalloproteinase. Modulation of u-PA expression by pressure may thus represent an important mechanism whereby hemodynamic forces regulate smooth muscle cell migration.  相似文献   
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25.
Twenty-two pathologic (including estrogen and progesterone receptor status) and four clinical features of 950 node-negative stage I invasive breast cancers from 950 women enrolled in the National Surgical Adjuvant Breast and Bowel Project protocol B-06 were analyzed for their possible prognostic significance. Univariate analyses revealed 10 characteristics that were significant at the 1% level. Only three of these--notably nuclear grade, histologic tumor type, and race--were found to be significant when entered into a Cox regression model. Patients whose tumors exhibited a good nuclear grade fared significantly better than those whose tumors were scored as poor. Similarly, a significantly better prognosis was noted when the histologic type of cancer was found to be "favorable" (mucinous, tubular, or papillary) than when it was "intermediate" (NOS, "Not Otherwise Specified," combination; typical medullary; and lobular invasive) or "unfavorable" (NOS pure and atypical medullary). Blacks exhibited a worse prognosis than whites. Survival was 94% at 8 years when the nuclear grade was good and the tumor type favorable, but only 54% when the nuclear grade was poor and tumor type unfavorable. Patients with one favorable and one unfavorable feature exhibited an intermediate survival. A brief overview as well as our own preliminary experience indicates that the combined use of these two prognostic pathologic parameters may be as good as and in some instances a better predictor of survival in node-negative patients than information derived from more "objective" methodologies such as flow cytometry, receptor analyses and tumor labeling indices or the demonstration of oncogene overexpression. Assessment of the pathologic parameters is simple, universally available, and quick and requires only modest training to be reproducible.  相似文献   
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27.
This report presents an analysis of several demographic discriminants of stomach cancer incidence for residents of the Pittsburgh Standard Metropolitan Statistical Area (SMSA) with the use of data collected as part of the Third National Cancer Survey, 1969-71. The Pittsburgh SMSA, one of nine areas included in the Third National Cancer Survey, was of particular interest in the study of stomach cancer, since area residents showed the highest age-adjusted incidence rate for cancer of this site while showing the fifth highest rate for all sites. To examine the data in greater detail, we used the variables of sex, race, nativity, and median income level to classify the cancer patients into homogeneous subgroups of census tracts of residence to allow comparisons of the average annual age-adjusted incidence rates among the groups. The data indicated that Pittsburgh SMSA residents showed stomach cancer incidence patterns that were generally consistent with earlier published reports; particularly when contrasted with appropriate population subgroups, higher rates appeared for males, for blacks, for lower income areas, and for areas with "large" proportions of foreign-born and foreign-stock residents. Furthermore, when one considered interactions among the factors, the relationship between ethnic composition and incidence appeared to supercede that of income among white males.  相似文献   
28.
散发内淋巴囊瘤VHL基因位点微卫星标志杂合性丢失的研究   总被引:1,自引:0,他引:1  
目的 探讨散发内淋巴囊瘤发病与VHL基因异常之间的关系。方法 采用组织微切割技术和多聚酶链式反应等方法对3例散发内淋巴囊瘤肿瘤细胞VHL基因位点染色体微卫星标志的杂合性丢失进行分析。结果 3例散发内淋巴囊瘤中有2例发生VHL基因位点微卫星标志的杂合性丢失,进一步的研究证实,该两例肿瘤细胞中分别存在着VHL基因第二外显子的异常。结论 VHL基因的异常导致其功能改变不但是VHL的致病原因,而且是散发性内淋巴囊瘤发病的重要的基因遗传学基础。  相似文献   
29.
对甲磺酰基苯乙烯环酮类衍生物的合成及抗炎活性   总被引:4,自引:0,他引:4  
敖桂珍  张奕华  季晖  邓钢 《药学学报》2004,39(10):803-807
目的寻找新型高效低毒的非甾体抗炎药。方法合成对甲磺酰基苯乙烯环酮类衍生物,用二甲苯致小鼠耳肿胀模型和角叉菜胶致大鼠足跖肿胀模型评价其抗炎活性,并考察连续经口给药对大鼠胃肠道(GI)的影响。结果合成了9个新化合物(ZA1-9),结构经IR,1HNMR,MS和元素分析确证。小鼠试验表明ZA3,5-9的抗炎活性与双氯芬酸钠(DC)和罗非昔布(RC)相当(P>0.05),大鼠试验显示ZA3,7,8的抗炎活性与DC和RC相当(P>0.05), ZA6的抗炎作用显著强于DC和RC(P<0.05),ZA3,5-9对GI损伤显著小于DC (P<0.05,P<0.01),与RC相当(P>0.05)。结论对甲磺酰基苯乙烯环酮类衍生物的抗炎作用较强,GI不良反应小,值得进一步研究。  相似文献   
30.
A new technique for the resection of cranial tumours and subsequent reconstruction using stereolithographic (SL) biomodelling and customized cranioplastic implants has been developed. The technique is based on a custom model of the tumour and surrounding skull from which the resection of the tumour and shape of the cranioplasty can be determined. A patient with a hyperostotic fronto-orbital meningioma was selected. CT was performed and SL biomodels manufactured. The surgeon marked the resection margin on the biomodel and a customized resection template was fashioned. The tumour was then resected from the biomodel and a customized acrylic implant was manufactured to reconstruct the defect. At surgery the tumour was exposed in a routine fashion and the template used to mark the resection margin. Once resected, the defect was reconstructed with the custom cranioplastic implant. The technique facilitated accurate surgical resection of the tumour and subsequent reconstruction. The surgeon reported several advantages of the technique including increased confidence, reduced operating time (at least 1 h), excellent cosmetic results, accuracy, and simplicity. The patient reported that the opportunity to see the biomodel, template and implant improved her understanding of the procedure.  相似文献   
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