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51.
Objectives: To determine the feasibility of sentinel node radiolocalization in stage N0 in head and neck squamous cell carcinoma and to gain insight as to whether the sentinel node could be prognostic of regional micrometastatic disease. Study Design: A prospective report on the application sentinel node radiolocalization in eight patients with N0 squamous cell carcinoma of the head and neck region. Methods: For each patient a peritumoral submucosal injection of filtered technetium (99mTc) prepared with sulfur colloid was performed immediately following intubation. After at least 30 minutes, focal areas of accumulation corresponding to a sentinel node were marked on the skin surface. Complete neck dissections were performed, and the sentinel nodes were identified for later histological evaluation and comparison to the remaining lymphadenectomy specimen. Results: Sentinel node radiolocalization accurately identified two or more sentinel lymph nodes in all eight cases. In one patient, two of the three lymph nodes containing micrometastatic disease were sentinel lymph nodes. There was no instance in which sentinel node was negative for micrometastatic disease while being positive in a nonsentinel lymph node. Conclusions: Accurate localization of the sentinel lymph node using radiolabeled sulfur‐colloid is feasible in patients with squamous cell carcinoma of the head and neck region. Although sentinel node radiolocalization in head and neck squamous cell cancer may potentially reduce the time, cost, and morbidity of regional lymph node management, more experience with technique is required before its role can be determined.  相似文献   
52.
幼儿第二语言(外语)获得成效之多因素研究   总被引:6,自引:0,他引:6  
【目的】 从语言和认知发展的角度研究幼儿第二语言的获得,探讨童学习外语的成效。【方法】 选择18~24个月、3-6岁正常幼儿,评价儿童的一般情况、语言发育水平(幼儿语言筛查表,WPPSI语言部分和PPVT)、中文和英文的语音分辨测验、英文发音准确性、记忆能力和英文学习成绩。研究的第一阶段为语音输入,18~24个月幼儿被分为两组,分别给予100h的中文和英文的语音输入。第二阶段,所有儿童参加14周的英语教学和测验。【结果】 70.9%儿童的家长重视学英文,高于重视中文获得的比例。是否经常听儿童磁带与中文词汇量有显著的正相关。英语成绩:女孩显著高于男孩;与年龄、中文和英文的语音分辨能力、WPPSI语言和PPVT的原始分、记忆能力呈显著的正相关。英语发音的准确性与年龄和中文语音分辨能力有显著的正相关。【结论】 幼儿学习L2:①应充分重视母语的发展;②无需从幼儿早期开始,在学龄前学习成效随年龄而提高;③女童的语言能力强于男童。④语音训练应考虑年龄和方法。  相似文献   
53.
Eight colorectal and 5 ovarian cancer patients were evaluated with preoperative immunoscintigraphy and intraoperative gamma probe detection of 111indium-labeled monoclonal antibody B72.3. Immunoscintigraphy detected the presence of tumor in every patient shown to have tumor at surgery. There was one false-positive scan. A total of 21 pathologically verified lesions were identified at surgery in the 11 patients with tumor. Immunoscintigraphy localized 12 (57%) and intraoperative gamma probe detection located 17 (81%) of the lesions. Intraoperative probe detection located 6 of 8 lesions smaller than 1 cm and 3 lesions that were not identified on initial surgical exploration. The gamma probe offers information that is complementary to immunoscintigraphy in that (1) it aids the surgeon in locating intra- and extra-abdominal lesions previously identified by immunoscintigraphy, (2) it locates lesions too small to be seen by immunoscintigraphy alone, (3) it locates lesions that otherwise might be missed at surgery, and (4) it provides objective evidence for adequacy of surgical resection of cancer in the abdominal cavity.  相似文献   
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55.
AIM: To compare bacillus Calmette-Guerin (BCG) with epirubicin in adjuvant therapy of superficial bladder transitional cell carcinoma, with respect to recurrence, progression and survival. Prognostic factors are also evaluated. METHODS: Between October 1991 and September 1999, all patients harboring superficial bladder cancers (Ta or T1) with any of the relevant criteria (stage>a, grade>1, size>1 cm, multiple or recurrent tumors), after complete transurethral resection were randomized to receive either 81 mg Connaught strain BCG or 50 mg epirubicin. Patients with recurrences were eligible to crossover, even repeatedly, until progression. Recurrence, progression and survival were analyzed in relation to initial treatment, patient characteristics and tumor characteristics. RESULTS: There were 209 patients included in the study, 149 men and 60 women. The mean age was 69.9 years (range, 24-92). The BCG group consisted of 102 patients and the epirubicin group contained 107 patients. Final analysis was made at a median follow up of 23, 47 and 61 months for recurrence, progression and survival, respectively. The 10-year Kaplan-Meier estimates for recurrence-free, progression-free and disease-specific survival were 61%, 78% and 80%, respectively, for the BCG group. The corresponding figures were 32%, 74% and 92%, respectively, for the epirubicin group. Time to recurrence differed significantly between two treatment groups (P=0.0004). Multiplicity increased the risk of recurrence, while grading influenced recurrence, progression and disease specific survival. CONCLUSIONS: Bacillus Calmette-Guerin prolonged time to recurrence when compared with epirubicin. Grading was shown to be a universal prognostic factor for recurrence, progression and disease specific survival.  相似文献   
56.
The purpose of the present study was to investigate substitutions in the D-loop of mitochondrial DNA (mtDNA) in sudden infant death syndrome (SIDS) and controls, since several observations indicate the involvement of mtDNA mutations in SIDS. These include elevated levels of vitreous humour hypoxanthine in SIDS victims, familial clustering without mendelian traits, and observations of increased sleepiness and a lower activity score in infants who later succumbed to SIDS. Eighty-two cases of SIDS and 133 controls were investigated and the D-loop sequences were recorded in the base-pair range 16 055-16 500 in the mtDNA sequence. The sequencing was carried out using the Applied Biosystems Sequenase dye terminator method and a ABD373A sequencer. The recorded D-loop sequences were compared with the Cambridge sequence and differences were recorded as substitutions. The SIDS cases had a tendency towards a higher substitution rate in the D-loop than the controls ( p = 0.088). This observation makes it interesting to search for deleterious mutations in other locations in the mtDNA.  相似文献   
57.
PURPOSE: To evaluate potential detrimental effects of exemestane on bone and lipid metabolism. PATIENTS AND METHODS: Postmenopausal women with early breast cancer were randomly assigned to exemestane 25 mg daily or placebo for 2 years in a double-blind setting. Primary objective was to evaluate the effect of exemestane on bone mineral density. Secondary objectives were effects on bone biomarkers, plasma lipids, coagulation factors, and homocysteine. Planned size was 128 patients. RESULTS: One hundred forty-seven patients were enrolled. All patients completed their 24-month visit except for those discontinuing treatment at an earlier stage. The mean annual rate of bone mineral density loss was 2.17% v 1.84% in the lumbar spine (P = .568) and 2.72% v 1.48% in the femoral neck (P = .024) in the exemestane and placebo arm, respectively. The mean change in T-score after 2 years was -0.21 for exemestane and -0.11 on placebo in the hip, and -0.30 and -0.21, respectively, in the lumbar spine. Exemestane significantly increased serum level and urinary excretion of bone resorption, but also bone formation markers. Except for a modest reduction in high-density lipoprotein cholesterol (P < .001) and apolipoprotein A1 (P = .004), exemestane had no major effect on lipid profile, homocysteine levels, or coagulation parameters. CONCLUSION: Exemestane modestly enhanced bone loss from the femoral neck without significant influence on lumbar bone loss. Except for a 6% to 9% drop in plasma high-density lipoprotein cholesterol, no major effects on serum lipids, coagulation factors, or homocysteine were recorded. Bone mineral density should be assessed according to the US Preventive Services Task Force guidelines.  相似文献   
58.
The risk and speed of progression from fibrosis to compensated and decompensated cirrhosis define the prognosis in liver diseases. Therefore, early detection and preventive strategies affect outcomes. Patients with liver disease have traditionally been diagnosed at an advanced stage of disease, in part due to lack of non-invasive markers. Ultrasound elastography to measure liver stiffness can potentially change this paradigm. The purpose of this review was therefore to summarize advances in the field of ultrasound elastography with focus on diagnosis of liver fibrosis, cirrhosis and clinically significant portal hypertension, techniques and limitations. Four types of ultrasound elastography exist, but there is scarce evidence comparing the different techniques. The majority of experience concern transient elastography for diagnosing fibrosis and cirrhosis in patients with chronic viral hepatitis C. That said, the role of elastography in other aetiologies such as alcoholic- and non-alcoholic liver fibrosis still needs clarification. Although elastography can be used to diagnose liver fibrosis and cirrhosis, its true potential lies in the possibility of multiple, repeated measurements that allow for treatment surveillance, continuous risk stratification and monitoring of complications. As such, elastography may be a powerful tool for personalized medicine. While elastography is an exciting technique, the nature of ultrasound imaging limits its applicability, due to the risk of failures and unreliable results. Key factors that limit the applicability of liver stiffness measurements are as follows: liver vein congestion, cholestasis, a recent meal, inflammation, obesity, observer experience and ascites. The coming years will show whether elastography will be widely adapted in general care.  相似文献   
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60.
Short-chain fatty acids (SCFA) in faeces were examined in 18 patients with the irritable bowel syndrome (IBS) during treatment with wheat bran or placebo. In the placebo period, the patients could be classified in accordance with the faecal concentrations of SCFA into one group with low concentrations (mean, 40 mmol/l; range, 19-77 mmol/l; 10 patients) and another with high concentrations (mean, 168 mmol/l; range, 145-187 mmol/l; 8 patients). The concentrations of SCFA differed (P less than 0.001) in both groups from concentrations found in faeces from a reference group of nine normal individuals (mean, 114 mmol/l; range, 93-155 mmol/l). Patients with low levels of SCFA had lower (P less than 0.001) mean stool mass and longer (P less than 0.05) transit times than those with high concentrations of SCFA in faeces. Ingestion of bran, although a precursor of SCFA, did not change faecal concentrations of SCFA. Abdominal pain, distension, and rumbling were not correlated to low or high concentrations of SCFA in faeces, nor did bran improve these symptoms when compared to placebo. The level of SCFA was rather constant intraindividually and independent of the variability of the daily faecal mass. It is concluded that patients with IBS apparently have continuously abnormal concentrations of SCFA in faeces, either high or low, which are unaffected by the treatment with bran and which hypothetically may be of pathophysiologic importance.  相似文献   
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