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131.
Objective To assess the accuracy of several published equations for predicting basal metabolic rate (BMR) in older women.

Design BMR was assessed in 116 healthy, older white women, aged 60 to 82 years, on three successive mornings by indirect calorimetry. Body composition was determined by dual energy X-ray absorptiometry or hydrostatic weighing. The measured BMRs were compared with values obtained from eight published prediction equations that used solely, or in various combinations, measures of height, weight, fat-free mass, age, and menopausal status.

Statistical analyses performed The root mean squared prediction error (RMSPE) was used to determine how accurately predicted BMR matched actual BMR for each subject. In addition, regression analysis was used to evaluate accuracy of predicted BMR vs directly measured BMR.

Results Predicted mean BMR determined using all eight equations was significantly correlated to measured BMR (P=.0001), accounting for 30% to 52% of the variance of measured BMR. When analyzed by RMSPE, however, the equations of Owen et al (1986), Fredrix et al (1990), and Harris-Benedict (1919) predicted actual BMR for each subject within an average of 116 kcal/day, and the equation of Cunningham (1980) resulted in the largest prediction error at 208 kcal/day.

Applications/conclusions The regression equations of Owen et al (1986), which used body weight, Fredrix et al (1990), which used body weight and age, and Harris-Benedict (1919), which used age, weight, and height as variables, were most accurate in predicting BMR in our sample of healthy older women. J Am Diet Assoc. 1995; 95:1387-1392.  相似文献   

132.
Despite the widespread conservative management of breast cancer, the pathologists' examination of these specimens is far from uniform. Pathologists sample margins differently, and even disagree on what constitutes a positive margin. This variability in the pathologic examination of the lumpectomy creates tremendous problems in analyzing the existing literature on the importance of positive margins. Herein is a discussion of the available data on the significance of margin assessment. We furthermore suggest a practical approach to examining margins with an emphasis on a functional orientation of the specimen with respect to the nipple. Only by adopting a uniform system of margin assessment can we begin to critically evaluate the importance of positive margins in segmental resections of the breast.  相似文献   
133.
The lighting environment where the baby born prematurely is placed is different from that experienced in utero. As early exposure to light may affect the immature visual system we have attempted to quantify the neonatal ocular light dose. Lighting surveys performed in 7 neonatal units (NNUs) suggested that mean unit illuminance was 470 lux (range 192-890 lux) and intensive care areas within the NNU were significantly brighter than their corresponding low dependency nurseries. The spectral power distribution of fluorescent lights in NNUs was weighted towards the blue end of the spectrum. Datalogging studies demonstrated that between about 30% and 98% of environmental light was incident on the eyelid, which acts as a predominantly red-pass filter, permitting 21% transmission at 700 nm with less than or equal to 5% transmission at 580 nm. Eye-lid opening frequency was quantified: 45% less than or equal to 26 weeks gestational age and decreasing to 7% at 28 weeks gestational age. The onset of the pupillary reflex to light was between 30 and 34 weeks postmenstrual age, the mean diameter was 3.46 mm before this event and 3.02 mm afterwards. Retinal irradiance values calculated from these data show that it is a function of postmenstrual age. Further studies are required to determine its effect on the immature visual system.  相似文献   
134.
135.
OBJECTIVE: To evaluate the success of the Southeast Asian Health Project in terms of client satisfaction with the prenatal care and other services. To obtain additional data about Southeast Asian women's health practices regarding childbearing. DESIGN: Survey through questionnaires administered as interviews. SETTING: In clients' homes or via telephone. PARTICIPANTS: 119 women from SEAHP's case files of recently delivered clients. MEASUREMENTS AND MAIN RESULTS: Interviews were conducted by four community workers fluent in Cambodian or Lao. The majority of women were satisfied with SEAHP, particularly the interpretation and education in native languages. Women were also satisfied with SEAHP, encouraging others to seek care. CONCLUSIONS: SEAHP appears to meet prenatal care needs of Southeast Asian women in Long Beach, California. More objective outcome data await analyses, but the program's approach may ensure access to and use of health services.  相似文献   
136.
The long-term effects of disease and treatment on electrophysiologicalmeasures of neurocognitive function were studied in childrenwho had survived acute lymphoblastic leukemia (ALL) for at least4 years and were currently in remission. We report here changesin cognitive processing time as shown by the latency of theP3 wave of the auditory event-related EEG potential (ERP). P3latency was significantly prolonged in long-term ALL surivors,as well as in patients successfully trreated for solid tumors(ST)outside the CNS who received similar chemotherapy but did notreceive prophylactic treatment to the CNS. P3 latencies werestrongly correlated with measures of school performance andIQ in these individuals. The similarity in P3 latency betweenthe ALL and ST groups suggests that the treatments used on thesepateints produce changes in electrophysiological responses thatare associated with mild, but significant, cognitive deficits.  相似文献   
137.
Published reports regarding the stability of morphine are at variance, especially in syringes used in patient-controlled analgesia (PCA) devices. In addition to the effects of container type and vehicle, reasons for this variation include the effect of excipients temperature and light during storage. Furthermore, the literature varies regarding the mechanisms of decomposition for morphine. To our knowledge, the stability of meperidine (pethidine) stored in plastic syringes has not been reported. The purposes of this study were to investigate the stability of morphine sulphate (1 and 5 mg/ml) and meperidine hydrochloride (5 and 10 mg/ml) in plastic syringes for use in PCA devices for a duration of 12 weeks, and evaluate the influence of light (240 foot-candies), temperature (-20, 4 and 23d?C), diluent (5% dextrose or normal saline), and drug concentration on the stability of these narcotic analgesics. Samples were taken bi-weekly for solutions protected from light and weekly for solutions exposed to light. Morphine sulphate and meperidine hydrochloride concentrations were quantified using independent, stability-indicating, high performance liquid chromatographic assays. The within-day and between-day coefficients of variation for these assays were 4% over each of the concentration ranges studied. Under the conditions of this study, it is proposed that although decomposition of morphine to its main product, pseudomorphine, can be interpreted using first-order kinetics, consecutive (to form the N-oxide) and parallel mechanisms (to form apomorphine) exist. Morphine solutions were more stable in normal saline than in 5% dextrose. SheIf-life data indicate that morphine is stable for at least 6 weeks when protected from light. Exposure to light accelerates morphine decomposition two to six-fold depending on the concentration, and the shelf-life is reduced to about 1 week in some instances. Meperidine solutions in both vehicles under all conditions had shelf-lives of at least 12 weeks. No effects of light were detected and no changes in solution colour were observed. This study illustrates that patients using PCA devices must be advised about shelf-lives as well as correct storage conditions to protect solutions of these drugs from environmental factors that may alter shelf-lives. Pharmacists should also note that other formulation factors such as: antioxidants, preservations, buffers, impurities, and the source and quality of containers, may significantly alter the shelf-lives of these drugs.  相似文献   
138.
The ethics of gene research.   总被引:1,自引:1,他引:0       下载免费PDF全文
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139.
Exogenous surfactant therapy (EST) in surfactant-deficient premature infants has been shown to improve lung compliance, decrease morbidity, and improve survival. Reports have demonstrated that newborns with congenital diaphragmatic hernia (CDH) have lung compliance, pressure-volume curves, and hyaline membrane formation resembling those changes seen in surfactant deficient premature newborns. We hypothesize that EST may also benefit infants with CDH. All high risk cases of prenatally diagnosed CDH at Children's Hospital of Buffalo from November 1988 to February 1991 were prospectively evaluated for EST. In those families who chose to participate, the surfactant preparation, Infasurf (100 mg/kg), was instilled into the newborn's lungs prior to the first breath. The remainder of the perinatal, neonatal, and surgical care was performed in a routine manner. Three high-risk prenatally diagnosed newborns with left CDH were treated with EST. All showed signs of decreased pulmonary compliance, but could still be adequately oxygenated and ventilated. Surgical correction was performed after stabilization and all required patch closures. Two of the three infants suffered no life-threatening episodes of pulmonary hypertension and all survived. These infants had many known indicators for poor outcome in CDH with an expected survival of less than 20%. We believe that EST in these neonates with CDH contributed to their survival with minimum morbidity. These results suggest that surfactant replacement for the high-risk neonate with CDH warrants further consideration and a randomized clinical trial is being planned.  相似文献   
140.
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