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71.
Background and Aim:  Although endoscopic papillectomy has been attempted in early stage ampullary cancer (pTis, T1), its curative role and indications remain uncertain. The present study was designed to assess the factors that predict malignancy and lymph node metastasis and to suggest potential indications for endoscopic papillectomy by analyzing clinicopathological data.
Methods:  We performed a retrospective analysis of clinical and histopathological data of 216 patients with ampullary cancer between 1991 and 2006.
Results:  No tumor in pTis stage had metastasized to lymph nodes and only 9% of tumors in pT1 had metastasized. Tumor size ( P  = 0.018), depth of invasion ( P  = 0.021) and venous invasion ( P  = 0.014) were found to be significantly related to lymph node metastasis. Cases with early stage ampullary cancer of less than 2 cm with a well-differentiated histology and no angiolymphatic invasion ( n  = 13) showed no lymph node metastasis and no recurrence during a median follow up of 35.9 months.
Conclusion:  Endoscopic papillectomy can be adopted as a viable alternative to surgery in patients with early stage ampullary cancer of less than 2 cm in size and with a well-differentiated histology. When a resected specimen has a well-differentiated histology, and there is no resection margin involvement and no angiolymphatic invasion, our findings indicate that subsequent radical surgery is unnecessary.  相似文献   
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73.
    
BACKGROUND No consensus has been reached in patients suspected of having inadequate bowel preparation regarding optimal salvage methods, which negatively affects the efficacy and quality of colonoscopy. The most ideal and reasonable rescue option involves early suspicion and identification of patients with inadequate preparation before sedation, additional oral ingestion of a suitable preparation formulation, and same-day colonoscopy.AIM To compare 0.5-L and 1-L polyethylene glycol containing ascorbic acid(PEG +Asc) as additional bowel cleansing methods after a 2-L split-dose PEG + Asc regimen in patients with expected inadequate bowel preparation before colonoscopy.METHODS Individuals with expected inadequate bowel preparation based on last stool form, such as turbid liquid, particulate liquid, or liquid with small amounts of feces, were randomized to either a 0.5-L PEG + Asc group or a 1-L PEG + Asc group. The primary endpoint was bowel preparation as assessed using the Aronchick bowel preparation scale(ABPS) and Boston bowel preparation scale(BBPS) scores. The secondary endpoints were cecal intubation time, withdrawal time, polyp detection rate(PDR), adenoma detection rate(ADR), individual compliance with additional PEG + Asc, and patient satisfaction.RESULTS Initially, 98 patients were included, but 8 were later excluded due to withdrawal of consent to participate in the study. Adequate bowel preparation(as assessed by ABPS) was observed in 80.9%(38/47) of subjects in the 0.5-L group and in88.4%(38/43) of subjects in the 1-L group(P = 0.617). Mean total BBPS was 6.7 points in the 0.5-L group and 7.0 points in the 1-L group(P = 0.458). ADRs and PDRs were similar in the two groups, and cecal intubation and withdrawal times were not significantly different. However, mean patient satisfaction score was significantly higher in the 0.5-L group(P = 0.041).CONCLUSION The bowel cleaning efficacy of additional 0.5-L PEG + Asc was not inferior to that of 1-L PEG + Asc. Additional 0.5-L PEG + Asc is worthwhile when inadequate bowel preparation is expected before colonoscopy.  相似文献   
74.
目的 研究感染华支睾吸虫的大鼠T淋巴细胞对寄生虫抗原或促有丝分裂原植物血凝素刺激后的体外增殖及细胞因子产生的免疫效应。 方法 观察感染华支睾吸虫的大鼠脾淋巴细胞和肠系膜淋巴结细胞 ,在促有丝分裂原PHA ,华支睾吸虫分泌排泄抗原 ,华支睾吸虫成虫粗抗原和异尖线虫幼虫粗抗原刺激下 ,体外淋巴细胞增殖及细胞因子的水平 ,包括IFN γ ,IL 2 ,IL 4,IL 1 0。 结果 肠系膜淋巴结的淋巴细胞增殖高于脾淋巴细胞。淋巴细胞浓度为 3× 1 0 6或 9× 1 0 6 细胞/孔时 ,脾脏和肠系膜淋巴细胞增殖均显著高于对照组 (P <0 .0 1 )。淋巴细胞数为 5× 1 0 6 细胞 /孔 ,刺激原浓度为 5或 1 0 μg/ml时 ,淋巴细胞活化明显。肠系膜淋巴结细胞的细胞因子 ,IFN γ和IL 1 0的产生水平显著增加。  结论 淋巴细胞浓度 5×1 0 6 细胞/孔和刺激原浓度 1 0 μg/ml的条件为激活T淋巴细胞增殖和细胞因子产生的最适培养条件。华支睾吸虫感染大鼠的成虫分泌排泄抗原在体内可能刺激淋巴细胞增殖和细胞因子产生  相似文献   
75.
In the present study, we evaluated the relationships of estimated desaturase activities with cardiometabolic risk factors including abdominal obesity, atherogenic lipoprotein phenotype and inflammation in Koreans. Ninety-three healthy volunteers participated in this cross-sectional study. LDL particle size was determined using gradient gel electrophoresis and inflammatory markers including C-reactive protein, soluble intercellular adhesion molecule-1, and adiponectin were measured. Stearoyl–coA desaturase, delta-6 desaturase and delta-5 desaturase were estimated as precursor to fatty acid ratios. The results showed that stearoyl–coA desaturase was correlated with body mass index (r = 0.235, p<0.05), triglyceride (r = 0.261, p<0.001), and HDL-cholesterol (r = −0.226, p<0.05). Stearoyl–coA desaturase was associated with only triglyceride (r = 0.283, p<0.01). Delta-6 desaturase was correlated with body mass index (r = 0.236, p<0.05), waist circumference (r = 0.218, p<0.05), triglyceride (r = 0.399, p<0.001), C-reactive protein (r = 0.333, p<0.001), soluble intercellular adhesion molecule-1 (r = 0.229, p<0.05), HDL-cholesterol (r = −0.325, p<0.01), LDL particle size (r = −0.297, p<0.01) and adiponectin (r = −0.233, p<0.05). In contrast, delta-5 desaturase was correlated with body mass index (r = −0.324, p<0.01), waist circumference (r = −0.276, p<0.01), triglyceride (r = −0.329, p<0.01), C-reactive protein (r = −0.215, p<0.05), HDL-cholesterol (r = 0.262, p<0.05) and LDL particle size (r = 0.278, p<0.01). Stepwise multiple regression analysis revealed that delta-6 desaturase (p<0.01) together with waist circumference (p<0.001) were found to be independent factors for determining plasma levels of C-reactive protein (R2 = 0.230). Estimated desaturase activities are closely associated with the features of cardiometabolic risk in Koreans.  相似文献   
76.
BACKGROUND/AIMS: It has been reported that the risk of gastric polyp is increased in various colonic polyposis syndromes or in series of patients with sporadic colonic polyps. However, there are only a few large case controlled studies of colon cancer incidence in gastric cancer patients who underwent colonoscopy. The aims of this study were to determine the incidence of colorectal neoplasm and to evaluate the necessity of colonoscopic surveillance in patients with gastric cancer. METHODS: We performed colonoscopy in 105 patients with gastric cancer who agreed to undergo colonoscopy before or after 6 months from gastric resection between January 2002 and December 2004 in Kangbuk Samsung hospital. As a control group, 269 consecutive, age and sex matched patients without gastric neoplasm on gastroscopy who underwent colonoscopy within 6 months for the evaluation of various gastrointestinal symptoms during the year 2004 were included. Endoscopic reports and pathological results were reviewed retrospectively. RESULTS: In the patient group, adenomatous polyps were diagnosed in 24/105 patients (22.9%) and colorectal adenocarcinoma in 10/105 patients (9.5%). In the control group, adenomatous polyps were diagnosed in 78/269 patients (29.0%) and colorectal adenocarcinoma in 2/269 patients (0.7%). The incidence of colorectal adenocarcinoma between the patient group and control group showed significant differences (odds ratio 11.04, p=0.003). CONCLUSIONS: The risk of colorectal adenocarcinoma increases significantly in patients with gastric cancer. We suggest that the patients with gastric cancer might carry a high risk for colorectal cancer whom require surveillance colonoscopy.  相似文献   
77.
To investigate the effects of a wake‐promoting drug, modafinil on regional cerebral blood flow (rCBF) in healthy volunteers, we performed 99mTc‐ethylcysteinate dimer single photon emission computed tomography (SPECT) before and after modafinil or placebo administration. Twenty‐one healthy subjects received single doses of 400 mg modafinil or placebo in a double blind randomized crossover study design. Administrations of modafinil or placebo in a subject were separated by a 2‐week washout. Brain SPECT was performed twice before and 3 h after modafinil or placebo administration. For statistical parametric mapping analysis, all SPECT images were spatially normalized to the standard SPECT template and then smoothed using a 12‐mm full width at half‐maximum Gaussian kernel. The paired t‐test was used to compare pre‐ versus post‐modafinil and pre‐ versus post‐placebo SPECT images. Differences in rCBF between post‐modafinil and post‐placebo conditions were also tested. Modafinil decreased Epworth and Stanford sleepiness scales whereas placebo did not. The post‐modafinil condition was associated with increased rCBF in bilateral thalami and dorsal pons, whereas the post‐placebo condition showed increased rCBF in a smaller area of the dorsal pons when compared with the drug naïve baseline condition. Compared with the post‐placebo condition, the post‐modafinil condition showed higher rCBF in bilateral frontopolar, orbitofrontal, superior frontal, middle frontal gyri, short insular gyri, left cingulate gyrus, left middle/inferior temporal gyri, left parahippocampal gyrus, and left pons. In healthy volunteers, modafinil increased wakefulness and rCBF in the arousal‐related systems and in brain areas related to emotion and executive function.  相似文献   
78.
BACKGROUND: The commercially available formulation of amlodipine is conjugated with besylate salt to increase water solubility. Recently, a new amlodipine salt formulation has been developed in which the free base of amlodipine is conjugated with a chemically different salt, adipate. OBJECTIVE: The goal of this study was to compare the antihypertensive effect and tolerability of amlodipine adipate with those of amlodipine besylate in patients with mild to moderate hypertension. METHODS: This was a multicenter, randomized, doubleblind, parallel-group study in which patients received 8 weeks of treatment with either amlodipine adipate or amlodipine besylate. The primary efficacy variable was noninferiority of the difference in mean changes from baseline in trough diastolic blood pressure (DBP) after 8 weeks of treatment. Secondary efficacy variables included mean changes in DBP, systolic blood pressure (SBP), and response rate (defined as the proportion of patients whose DBP was <90 mm Hg or whose DBP had decreased from baseline by > or =10 mm Hg). The incidence of adverse events (AEs) was also assessed. RESULTS: Two hundred eleven patients were randomly assigned to receive amlodipine adipate (n = 106) or amlodipine besylate (n = 105). Study patients were primarily female (54.5%), with a mean (SD) age of 52.2 (9.6) years and a mean body weight of 67.1 (10.2) kg; there were no between-group differences in demographic profiles. After 4 weeks of randomized treatment, 58 (27.5%) patients (29 [27.4%] amlodipine adipate, 29 [27.6%] amlodipine besylate) had not achieved a mean DBP <90 mm Hg, and their dose was doubled. Mean DBP changes at 8 weeks were -15.2 (7.3) mm Hg in the amlodipine adipate group and -14.2 (7.4) mm Hg in the amlodipine besylate group (P = NS). Because the 95% CI for the difference in mean DBP changes between groups (-0.53 to 2.55) was within the prespecified lower limit (-4 mm Hg), amlodipine adipate was considered noninferior to amlodipine besylate. Mean SBP changes were -24.9 (12.1) mm Hg in the amlodipine adipate group and -22.0 (14.7) mm Hg in the amlodipine besylate group (P = NS). The response rates were 92.0% for amlodipine adipate and 95.4% for amlodipine besylate (P = NS). The overall incidence of clinical AEs was 20.8% in the amlodipine adipate group and 25.7% in the amlodipine besylate group (P = NS). Drug-related clinical AEs occurred in 5.7% and 12.4% of patients in the respective treatment groups (P = NS). Serum uric acid levels decreased significantly from base-line in both groups (P < 0.001). CONCLUSIONS: Eight weeks of treatment with amlodipine adipate produced significant reductions from baseline in blood pressure in these patients with mild to moderate hypertension. The efficacy of amlodipine adipate was not inferior to that of amlodipine besylate. Tolerability was comparable between the 2 treatment groups.  相似文献   
79.
The present study sought to elucidate the role of induction and consolidation therapy in elderly patients. We retrospectively collected data of 477 patients who were aged over 60 years at the time of acute myeloid leukemia (AML) diagnosis. The median overall survival (OS) was 339 days in the induction group (n = 266) and 86 days in the best supportive care group (n = 211) (P < 0.001). In the induction group, the complete remission (CR) rate was 58.3 %, and treatment-related death was 15.4 %. Successful induction was related to good performance [Eastern Cooperative Oncology Group (ECOG <2)] [hazard ratio (HR) 3.215; P = 0.002]. Mortality correlated with failure to achieve CR (HR 4.059; P < 0.001) and poor performance status (ECOG >2) (HR 2.731; P = 0.035). In CR patients, poor karyotype and absence of consolidation (HR 2.313; P = 0.003) correlated with mortality. More than one cycle of consolidation was associated with better OS (P < 0.001). Lack of salvage therapy was associated with mortality in patients who did not achieve CR (HR 3.223; P = 0.005). Intensive induction in patients with good performance and >1 cycle of consolidation after CR may be the best strategy for improving OS in elderly AML patients.  相似文献   
80.
The nucleocapsid (N) protein of rinderpest virus (RPV) is one of the most abundant and immunogenic viral proteins expressed during natural or experimental infection. To identify immunogenic epitopes on the N protein, different forms of RPV N protein, including the full-length protein (N1-525), an amino-terminal construct (N1-179), and a carboxy-terminal construct (N414-496), were expressed in Escherichia coli as glutathione S-transferase (GST) fusion proteins. The antigenicity of each recombinant protein was evaluated by Western immunoblotting. All recombinants were recognized by hyperimmune RPV bovine antisera, indicating that immunoreactive epitopes may be present at both ends of the N protein. However, GST-N414-496 was much more antigenic than GST-N1-179 when tested with sera from vaccinated cattle, suggesting that an immunodominant or highly immunogenic epitope(s) may be located at the carboxy terminus of the N protein. Epitope mapping with overlapping peptides representing different regions of the carboxy terminus (amino acids 415 to 524) revealed three nonoverlapping antigenic sites in regions containing the residues 440VPQVRKETRASSR452 (site 1), 479PEADTDPL486 (site 2), and 520DKDLL524 (site 3). Among these, antigenic site 2 showed the strongest reactivity with hyperimmune anti-RPV bovine sera in a peptide enzyme-linked immunosorbent assay but did not react with hyperimmune caprine sera raised against peste-des-petits-ruminants virus, which is antigenically closely related to RPV. Identification of an immunodominant linear antigenic site at the carboxy terminus of the N protein may provide an antigen basis for designing diagnostics specific for RPV.  相似文献   
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