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71.
Taylor  GA; Fitz  CR; Miller  MK; Garin  DB; Catena  LM; Short  BL 《Radiology》1987,165(3):675-678
Findings at neuroimaging in 100 consecutive infants treated with extracorporeal membrane oxygenation (ECMO) are presented. Imaging in these infants consisted of pretreatment cranial ultrasonography (US), daily US studies while on ECMO, and follow-up cranial computed tomography (CT) after treatment. There were findings of abnormalities in 43 patients. Thirty had intracranial bleeding, often of unusual extent and distribution. Thirteen additional infants had nonhemorrhagic abnormalities alone. Bleeding considered to be major was seen in 12% of infants. Large parenchymal hemorrhages and infarcts, cerebellar hemorrhages, and diffuse edema were the most significant abnormalities, with a 50% mortality (eight of 16 patients). No lateralization was noted with respect to distribution of bleeding sites or areas of nonhemorrhagic abnormalities. US was a sensitive but imperfect screening tool for intracranial abnormalities. Abnormalities missed with US included peripheral and small parenchymal lesions, subarachnoid hemorrhage, cerebral atrophy, and sagittal sinus thrombosis.  相似文献   
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73.
The primary purpose of fitness and body composition standards in the military has always been to select individuals best suited to the physical demands of military service. Obesity has reached epidemic proportions globally, and may have adverse consequences for the military: a worsening prevalence of obesity in young civilian adults could hinder the recruitment and maintenance of military manpower. This review explores the impact of obesity on suitability for employment in defence force careers and any potential impact on long-term occupational health. Studies containing data on obesity and the military were identified from an electronic database. Thirty-eight papers were identified and 17 were included in this review. There is a limited body of evidence available to ascertain whether or not obese individuals are suitable for employment in the military. There are a number of key issues that need to be addressed before a definitive conclusion can be drawn. These include the future health of obese personnel recruited into the military and subsequent implications for health services, costs to the organization and military readiness, and the ability of an obese person to be an active member of the military workforce. Future research should be targeted towards these areas in order to determine the implications of obesity for recruitment and retention of defence force personnel.  相似文献   
74.
污水中汞的微波消解冷原子吸收测定法   总被引:3,自引:0,他引:3  
目的 改进冷原子吸收法测定污水中汞的消解方法。方法 采用王水(1+1)微波消解法代替KMnO4-K2S2O8消解法测定污水中的汞。结果 王水(1+1)微波消解水样测定污水中汞,方法的线性范围为0~10.0μg/L,检出限为0.25μg/L,相对标准偏差小于2.7%,加标回收率为95.0%-102.0%。结论 与KMnO4-K2S2O8消解法相比,该方法具有较高的灵敏度和精密度,操作简单,结果可靠,适用于环境监测分析。  相似文献   
75.
The diagnostic value of biphasic radiographic examination of the stomach and duodenum was compared with that of fiberoptic endoscopy in a prospective, blinded study of 385 patients with dyspepsia. This investigation was directed at gastric malignancies and peptic ulcers. Methodologically there is no absolute standard for a study of this kind because histologic examination is useful for detection of cancer but inadequate for ulcers. As an alternative, kappa indexes and the sensitivity and specificity, as derived by Hui and Walter, were calculated and compared. For the detection of gastric carcinoma, radiographic and endoscopic findings had almost perfect agreement beyond chance. For gastric ulcers, radiography and endoscopy had substantial agreement, which became perfect if small ulcers (less than 5 mm) were excluded. For duodenal ulcers, radiography had a lower sensitivity than endoscopy; this disagreement disappeared if small ulcers were excluded. Both methods have equal merit; choice of the initial diagnostic procedure will therefore depend on cost, discomfort to the patient, and risk of complications.  相似文献   
76.
Gooding  GA; Okerlund  MD; Stark  DD; Clark  OH 《Radiology》1986,161(1):57-64
Parathyroid scintigraphy using a double-tracer (T1-201, Tc-99m) subtraction technique depicted 17 of 23 (74%) parathyroid adenomas in patients with and without previous neck operations. High-resolution (10-MHz) ultrasound (US) depicted 18 (78%) of these adenomas. Average tumor size depicted by US was 17 X 10 X 8 mm (excluding a giant adenoma) and 19 X 10 X 9 mm by scintigraphy. Alone, neither modality was particularly sensitive in the depiction of primary hyperplasia of the parathyroid glands, but combined techniques were more effective than the use of a single modality. With both US and T1-201 scintigraphy, only two of 23 cases of parathyroid adenoma in the neck were missed, and none of the eight cases of secondary hyperplasia were missed. In 11 patients who had previously undergone neck surgery, parathyroid tumors were identified in eight by either US or double-tracer scintigraphy. Preoperative parathyroid imaging with double-tracer scintigraphy and high-resolution US is suggested for patients with hyperparathyroidism, particularly in those patients who have had previous parathyroid surgery.  相似文献   
77.
78.
The authors evaluated magnetic resonance (MR) images obtained with intravenously administered gadolinium in ten patients who had facial paralysis and no facial nerve tumor. In patients with either Bell palsy (four patients) or facial paralysis after temporal bone surgery (six patients), intratemporal facial nerve enhancement was seen. Facial nerve enhancement on MR images proved to be a nonspecific finding.  相似文献   
79.
本文研究了复方阿斯匹林片中阿斯匹林、非那西丁和咖啡因含量同时测定的紫外分光光度法的最佳实验条件,并简述偏最小二乘法(PLS)在多组分同时测定中的基本原理和应用。三组分模拟试样回收率平均值的置信区间分别为100.1±0.23%,100.0±0.25%和100.1±0.33%(置信度95%)。PLS法是一种理想的多组分测定方法,计算速度较快,结果更准确可靠,尤其适用于成批试样的分析,为微机控制的紫外可见分光光度计提供了一种新方法。  相似文献   
80.
OBJECTIVE: To determine the effect of a high-protein (HP) diet compared with a low-protein (LP) diet on weight loss, resting energy expenditure (REE), and the thermic effect of food (TEF) in subjects with type 2 diabetes during moderate energy restriction. RESEARCH DESIGN AND METHODS: In this study, 26 obese subjects with type 2 diabetes consumed a HP (28% protein, 42% carbohydrate) or LP diet (16% protein, 55% carbohydrate) during 8 weeks of energy restriction (1,600 kcal/day) and 4 weeks of energy balance. Body weight and composition and REE were measured, and the TEF in response to a HP or LP meal was determined for 2 h, at weeks 0 and 12. RESULTS: The mean weight loss was 4.6 +/- 0.4 kg (P < 0.001), of which 4.5 +/- 0.4 kg was fat (P < 0.001), with no effect of diet (P = 0.6). At both weeks 0 and 12, TEF was greater after the HP than after the LP meal (0.064 vs. 0.050 kcal x kcal(-1) energy consumed x 2 h(-1), respectively; overall diet effect, P = 0.003). REE and TEF were reduced similarly with each of the diets (time effects, P = 0.02 and P < 0.001, respectively). CONCLUSIONS: In patients with type 2 diabetes, a low-fat diet with an increased protein-to-carbohydrate ratio does not significantly increase weight loss or blunt the fall in REE.  相似文献   
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