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61.
Objective: To discuss appropriate endpoints for research designed to prevent obesity. Research investigating practical solutions to the complex multi‐factorial global obesity epidemic may be stalled by undue emphasis on reduced body weight as the only acceptable endpoint. Approach: Considering prevention research in cardiovascular disease and tobacco control, we contend that investigations of intermediate endpoints make an important contribution to the multi‐faceted approach needed to combat the complex problem of obesity. Conclusion: Intermediate endpoints are respected in other public health areas: reductions in risk factors such as high blood cholesterol or smoking are acceptable study endpoints for research aimed at reducing heart disease or lung cancer. Likewise, practical endpoints can be valuable in studies investigating interventions to reduce identified and potential intermediate risk factors for obesity, such as soft drink consumption. Implications: Reduced obesity is the global aim but obesity is not caused by one exposure and will not be solved by a single modality intervention. A wider debate about endpoint selection may assist research which identifies individual building blocks of obesity prevention in the same way as individual gene mapping contributed to the Human Genome Project.  相似文献   
62.
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   
63.
Color Doppler ultrasound (US) with point-spectral analysis was performed on eight patients with postbiopsy renal transplant arteriovenous fistulas. Waveform analysis of the supplying artery documented decreased resistive indices in all cases and increased flow velocities in seven. The peak-systolic flow velocity in the arteries supplying the fistulas ranged from 55 to 180 cm/sec (mean, 92 cm/sec), while the range in normal arteries was 20-52 cm/sec (mean, 32 cm/sec). The resistive indices of the arteries supplying the fistulas ranged from 0.31 to 0.50 (mean, 0.45), while the resistive indices of the normal arteries ranged from 0.60 to 0.92 (mean, 0.74). Arterialization of the venous waveform from the draining vein was also documented in all cases. In six cases, the increased flow velocities resulted in increased color saturation toward white in the supplying artery (n = 2) or in both the artery and the draining vein (n = 4), which was detectable on the realtime image. In six cases, flow turbulence resulted in localized tissue vibration, which appeared as random color assignment in extravascular renal parenchyma adjacent to the fistula. Knowledge of these imaging and Doppler characteristics should aid in the identification of renal transplant arteriovenous fistulas with color Doppler US.  相似文献   
64.
Vitamin supplementation of patients receiving haemodialysis   总被引:1,自引:0,他引:1  
In order to assess the necessity of vitamin supplementation for patients who are receiving haemodialysis, measurements of vitamin status were made, and both dietary and supplementary intakes were assessed, in 26 patients who were undergoing haemodialysis. Blood samples were collected from these patients before they underwent haemodialysis, after an overnight fast, for the measurement of plasma retinol, alpha-tocopherol and ascorbate levels. Serum and erythrocyte folate levels were measured also. Thiamin status was assessed by the effect of added thiamin pyrophosphate on erythrocyte transketolase activity and pyridoxine status was assessed by the effect of added pyridoxal-5'-phosphate on erythrocyte aminotransferase activity. All patients had elevated plasma retinol levels; 48% of patients had elevated plasma alpha-tocopherol levels; the plasma ascorbate level was low in 50% of patients but was elevated in 25% of patients; and plasma and erythrocyte folate levels were elevated in 76% and 91% of patients, respectively. Thiamin status was normal in all but one patient and the pyridoxine level appeared to be low in two other patients. Many patients had low dietary intakes of vitamin C, folate and vitamin B6. We conclude that supplements of vitamins A and E are not required and, when dietary intakes of water-soluble vitamins are marginal, these should be supplemented at a dose as near as possible to the recommended dietary intake.  相似文献   
65.
66.
We treated 101 patients at our stone facility with the Dornier HM3 lithotriptor modified with the anesthesia-free design upgrade. A protocol designed by our anesthesiologists consisting of intravenous and intramuscular injections for sedation was used without any general or regional anesthesia required. Pre-medication with intramuscular meperidine and promethazine, and oral diazepam was sufficient sedation in 43 patients, while 37 required additional intravenous meperidine and/or midazolam during the procedure, 16 were treated with intraprocedural medication alone and 5 required no medication at all. Care before, during and after the procedure was rendered by the urology staff for patients in American Society of Anesthesiologists risk category I or II. Treatment was successfully completed in all patients without complications. We compared this group to the 99 patients treated consecutively before the modification. Voltage used, number of shocks and stone burden were comparable in the 2 groups but average treatment time was prolonged with the upgraded equipment (39.2 versus 27.1 minutes) to a significant degree (p less than 0.001).  相似文献   
67.
Peripheral polyneuropathy is the most frequent complication of diabetic mellitus. In spite of many clinical trials of different specific interventions for diabetic polyneuropathy, intensive glycemic control remains the only effective specific therapy currently available for this troublesome complication. This systematic overview reports the status of current clinical trials in diabetic polyneuropathy with an emphasis on those interventions directed towards specific pathophysiological derangements. A discussion of clinical trials of agents directed towards relieving painful symptoms of diabetic polyneuropathy concludes this overview.  相似文献   
68.
69.
The key to nursing retention is to be sensitive to the pressures and demands placed on staff nurses who want to provide and take pride in giving quality patient care. If an institution has many critical care nursing vacancies, it is important to avoid pushing the remaining nurses beyond human limits. It may even be necessary to close beds to keep the remaining nurses, rather than allow the stress of the nursing shortage to cause them to resign too.  相似文献   
70.
BACKGROUND: The extent to which age plays a role in the underutilization of angiotensin-converting enzyme (ACE) inhibitors in heart failure patients has not been well studied. METHODS: We studied age-related variation in the use of ACE inhibitors in older Medicare beneficiaries discharged alive in Alabama with a diagnosis of heart failure with left ventricular systolic dysfunction. RESULTS: A total of 285 patients had a mean age +/- SD of 78 +/- 6.9 years; 59% were female and 21% were African American. Of the 285 patients, 181 (63%) were prescribed ACE inhibitors at discharge. Therapy with ACE inhibitors was initiated in 47% of the patients. Compared with patients 65 to 74 years, those 85 years and older had lower odds of receiving ACE inhibitors at discharge. Among patients not admitted on an ACE inhibitor, those 85 years and older also had lower odds of ACE inhibitor therapy being initiated. CONCLUSION: The overall rate of ACE inhibitor use was low, and age of 85 years and older was independently associated with lower use and initiation of ACE inhibitors. Opportunities remain to increase the use of ACE inhibitors in older patients with heart failure.  相似文献   
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