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101.
Elevated body mass index and mortality risk in the elderly   总被引:2,自引:0,他引:2  
The purpose of this report was to perform a systematic review and meta-analysis of the studies examining the impact of an elevated body mass index (BMI) on mortality risk in elderly (> or =65 years) men and women. A variance-based method of meta-analysis was used to summarize the relationships from available studies. The summary relative risk of all-cause mortality from the 26 analyses that included a risk estimate for a BMI within the overweight range was 1.00 (95% confidence intervals, 0.97-1.03). The summary relative risk of all-cause mortality for the 28 analyses that included a risk estimate for a BMI within the obese range was 1.10 (1.06-1.13). These calculations indicate that a BMI in the overweight range is not associated with a significantly increased risk of mortality in the elderly, while a BMI in the moderately obese range is only associated with a modest increase in mortality risk.  相似文献   
102.
BACKGROUND: Our objective was to analyze retrospectively our experience with 19 patients who had metastatic germ cell testicular tumor and had undergone resection of pulmonary metastases following chemotherapy. We wished to determine the necessity of thoracic surgery on these patients. METHODS: Of 103 patients in need of postchemotherapeutic surgery for metastatic germ cell testicular tumors, 19 patients (mean age 31) underwent surgery for thoracic masses following cis-platin based chemotherapy. Resection of pulmonary metastases was performed on patients with normal tumor markers after chemotherapy, who did not achieve complete radiological remission. Histopathological findings, correlation with the pathology of abdominal surgery and probable prognostic factors for disease-free and overall survivals were evaluated. RESULTS: Disease-free and overall survival rates were 14/19 (73%) and 16/19 (84%), respectively, within a median follow-up time of 30 months (15-212 months). Patients with and without viable tumor cells in their thoracic histopathological specimen had 40% and 85% disease-free survival rates, respectively (P < 0.05). Eight patients had both abdominal and thoracic postchemotherapy surgery. Only two (25%) of these patients had the same histopathological features at both sites. CONCLUSIONS: All patients with residual thoracic masses must be considered candidates for surgery, because there are no predictive factors to determine the thoracic pathology without surgery. With the resection of the pulmonary metastases only, surgery can be performed without significant morbidity and is essential to select patients for further chemotherapy, to remove all visible masses and to provide histopathological confirmation. Patients with viable tumor cells in the thoracic surgical specimen have a poor prognosis.  相似文献   
103.
目的探讨电视纵隔镜检查术(video-mediastinoscopy,VM)在肺癌术前分期、纵隔肿物诊断和恶性胸腔积液诊治中的价值。方法采用全麻单腔螺纹气管插管,48例行颈部纵隔镜术,33例行胸骨旁纵隔镜检查术,47例行经肋间纵隔镜术。结果125例经电视纵隔镜术后确诊:肺腺癌38例,肺转移性低分化鳞癌33例,结核9例,淋巴结炎症8例,肺小细胞癌7例,胸腺鳞状细胞癌6例,非霍奇金淋巴瘤5例,纵隔神经母细胞瘤4例,胸腺瘤4例,胸膜间皮瘤3例,霍奇金淋巴瘤2例,后纵隔神经鞘瘤2例,结节病1例,胸腺增生1例,类癌1例,中纵隔原始神经外胚叶肿瘤1例。1例电视纵隔镜检查纵隔淋巴结为反应性增生,行左下肺叶切除,病理为鳞癌。2例术前纤维支气管镜病理确诊左下肺鳞癌,电视纵隔镜检查右气管旁淋巴结转移。术中发生气胸1例、出血1例、喉返神经麻痹和切口感染各2例。结论电视纵隔镜术不但是肺癌术前病理分期、纵隔疾病的重要检查方法,而且也是诊治恶性胸腔积液的简便方法。  相似文献   
104.
(Received for publication on Nov. 14, 1996; accepted on May 12, 1997)  相似文献   
105.
The intraperitoneal mass most commonly encountered after blunt abdominal truama is a hematoma. However, one must also consider unusual bulky tumors that can have imaging characteristics similar to those of hematoma. The most typical of these neoplasms is lymphoma, but a desmoplastic small cell tumor also may be observed. The presentation and imaging findings of a desmoplastic small tumor are described.  相似文献   
106.
Left ventricular (LV) wall thickness and muscle mass are importantmeasures of LV hypertrophy. In 24 patients LV end-diastolicwall thickness and muscle mass were determined (two observers)by digital subtraction angiocardiography (DSA) and conventionalLV angiocardiography (LVA). Wall thickness was determined overthe anterolateral wall of the left ventricle according to thetechnique of Rackley (method 1) or by planimetry (method 2).Seventeen patients were studied at rest and seven during dynamicexercise. Wall thickness correlated well between LVA and DSA;the best correlations were obtained by a combined subtractionmode using either method 1 or 2 (method 1, r0–80; method2,r0. 75). The standard error of estimate of the mean (SEE) wasslightly lower for method 2 ( 10%) than for method 1 ( 13%).DSA significantly overestimated wall thickness by 5–7%with method 1 and underestimated by 12–14% with method2. Muscle mass correlated well between LVA and DSA; the SEEwas 15% for method 1 and 12% for method 2. Overestimation ofmuscle mass by DSA was 7–11% with method 1 and underestimationwas 13–15% with method 2.It is concluded that LV wallthickness can be determined accurately by DSA with an SEE rangingbetween 10 and 13%. Determination of LV muscle mass is slightlyless accurate and the SEE is slightly larger ranging between13 to 17%. With method 1, wall thickness and muscle mass wereover estimated and with method 2 underestimated.  相似文献   
107.
Tryptamine (TA) occurs in trace levels in the brain, but its role in the central nervous system is not clear. However, there is evidence that TA may be a neuromodulator since it binds to specific binding sites in the brain. TA was measured as a diheptafluorobutyryl derivative in rat whole brain by capillary gas chromatography—mass spectrometry using negative chemical ionization (NCI) and single ion monitoring (SIM). d4-TA was used as the internal standard. The ions m/z 532 and m/z 536 were monitored to identify TA and d4-TA, respectively and to calculate the concentration of TA in rat whole brain which was found to be 0.19 ± 0.08 ng g−1 (n = 8). The results confirm the earlier TA concentrations measured by GC—MS using positive electron impact ionization. However, NCI improved the signal/noise ratio of the method increasing its sensitivity for TA.  相似文献   
108.
Two iliac crest needle biopsies were taken from a 43-year-old lead-poisoned woman during and after completion of a Ca-EDTA treatment. By atomic absorption spectroscopy the first and second biopsy were found to contain 56, respectively 41.6 g lead/g wet tissue. In both biopsies 36% of the lead was extractable in 0.1 N HCl. Electron microbeam X-ray analysis proved to have too low sensitivity for quantitation of the lead in these biopsies. Laser microbeam mass analysis (LAMMA), performed only on the second biopsy, revealed a high and fairly constant residual lead concentration in all bone marrow cell nuclei (approximately 55 g/g) and a low lead concentration in the cytoplasm of the same cells (4–12 (g/g). The extracellular bone matrix lead was greatly concentrated in the superficial 3–6 m osteoid zone of the bony trabeculae and totally absent from deeper parts of the mineralized matrix. The LAMMA results are in good agreement with those of subcellular fractionation experiments and atomic absorption spectroscopy, provided that the relative volume fraction of nucleus and cytoplasm is accounted for. The high residual osteoid lead after completed chelation therapy indicates that lead has a stronger affinity for the organic than the mineral components of bone matrix.  相似文献   
109.
目的 通过检测健康志愿者的羧酸酯酶1 (carboxylesterase 1,CES1)和羧酸酯酶2 (carboxylesterase 2,CES2)的基因多态性和基因表达水平,探索CES1和CES2在代谢中的作用。方法 从48例健康志愿者获得血样并提取DNA,对DNA进行二代基因测序,并提取总RNA检测基因表达量。使用多元线性回归分析CES1和CES2基因表达量与性别、年龄、体质量指数(body mass index, BMI)的关系。结果 CES1的基因表达量为141.8(72.7,237.8),CES2的基因表达量为74.4(30.8,133.6)。多元线性回归分析中,BMI与CES2的基因表达有关,性别、年龄和BMI与CES1的基因表达无关。发现CES1 20个基因变异,其中10个会引起氨基酸序列改变;发现CES2 6个基因变异,其中2个引起氨基酸序列改变。结论 发现CES2的表达水平与BMI相关,CES1的表达水平与BMI无明显相关,基因预测结果提示CES1的遗传变异可能影响其功能表达。  相似文献   
110.
刘妍慧  陈树春 《中国全科医学》2023,26(12):1422-1428
近年来,欧洲临床营养与代谢学会(ESPEN)和欧洲肥胖研究学会(EASO)的专家组成员对肌肉减少性肥胖(SO)的相关研究进行了系统地评价。2022年2月,ESPEN和EASO共同发布了《肌肉减少性肥胖的定义和诊断标准共识》,该共识对SO的定义和诊断进行了详细的阐述,旨在就SO的定义和诊断达成共识,为研究人员和临床工作者提供参考依据,以推进SO预防和治疗的发展。本文主要对《肌肉减少性肥胖的定义和诊断标准共识》中SO的定义,诊断流程包括筛查、诊断和分期标准,拟采用的方法和相关的参数等主要内容进行梳理和解读,旨在为国内医务工作者提供更多参考。  相似文献   
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