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51.
Rapidly available glucose in foods: an in vitro measurement that reflects the glycemic response 总被引:8,自引:0,他引:8
Englyst KN Englyst HN Hudson GJ Cole TJ Cummings JH 《The American journal of clinical nutrition》1999,69(3):448-454
BACKGROUND: A chemically based classification of dietary carbohydrates that takes into account the likely site, rate, and extent of digestion is presented. The classification divides dietary carbohydrates into sugars, starch fractions, and nonstarch polysaccharides, and groups them into rapidly available glucose (RAG) and slowly available glucose (SAG) as to the amounts of glucose (from sugar and starch, including maltodextrins) likely to be available for rapid and slow absorption, respectively, in the human small intestine. OBJECTIVE: We hypothesize that RAG is an important food-related determinant of the glycemic response. DESIGN: The measurement of RAG, SAG, and starch fractions by an in vitro technique is described, based on the measurement by HPLC of the glucose released from a test food during timed incubation with digestive enzymes under standardized conditions. Eight healthy adult subjects consumed 8 separate test meals ranging in RAG content from 11 to 49 g. RESULTS: The correlation between glycemic response and RAG was highly significant (P < 0.0001) and a given percentage increase in RAG was associated with the same percentage increase in glycemic response. After subject variation was accounted for, RAG explained 70% of the remaining variance in glycemic response. CONCLUSIONS: We show the significance of in vitro measurements of RAG in relation to glycemic response in human studies. The simple in vitro measurement of RAG and SAG is of physiologic relevance and could serve as a tool for investigating the importance of the amount, type, and form of dietary carbohydrates for health. 相似文献
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53.
Mock CN Abantanga F Cummings P Koepsell TD 《Bulletin of the World Health Organization》1999,77(12):955-964
Injury is an increasingly significant health problem in most low-income countries. However, strategies for preventing injury have not been well addressed. The present study was carried out to measure the incidence and outcome of various mechanisms of injury in Ghana in order to provide data for use in developing priorities for injury prevention efforts. For this purpose, using two-stage cluster sampling and household interviews, we surveyed 21,105 persons living in 431 urban and rural sites. During the preceding year, 1609 injuries resulting in one or more days of loss of normal activity were reported. Injury-related mortality was slightly higher in the urban (83 per 100,000) than in the rural area (53 per 100,000). However, the burden of disability from nonfatal injuries, as assessed by disability days, was higher in the rural (4697 disability days per 1000 person-years) than in the urban area (2671 days per 1000 person-years). Based on incidence rates and disability times, the major types of injury in the urban area were transport-related injury and falls. In the rural area, agricultural injuries predominated, followed by falls and transport-related injury. In rural and urban areas combined, 73% of motor vehicle-related injuries involved commercial vehicles. In this and other similar developing-country settings, injury prevention efforts should focus on falls and on transport safety in both urban and rural areas, with special attention being paid to commercial vehicles. In rural areas, agricultural injuries contributed the largest burden of morbidity, and should be a priority for prevention efforts. 相似文献
54.
Frisoni GB Rozzini L Gozzetti A Binetti G Zanetti O Bianchetti A Trabucchi M Cummings JL 《Dementia and geriatric cognitive disorders》1999,10(2):130-138
INTRODUCTION: Behavioral disturbances in patients with Alzheimer's disease (AD) are ill-defined conditions. We hypothesize that the many behavioral disturbances hitherto described and studied might be grouped into few syndromes with separate determinants and correlates. PATIENTS AND METHODS: 162 consecutive patients with probable AD admitted to a dementia unit were assessed by the UCLA Neuropsychiatric Inventory (NPI). RESULTS: Factor analysis was carried out on NPI subscales, leading to three syndromes: 'mood', 'psychotic' and 'frontal'. Patients with the 'psychotic' syndrome were older, had older age at dementia onset, had poorer cognition, were more often males, and had faster rate of dementia progression. Patients with the 'frontal' syndrome had higher education, longer disease duration, and slower rate of progression. DISCUSSION: Some combinations of behavioral disturbances occur more frequently together and might represent separate behavioral syndromes. Different clinical correlates of the syndromes suggest separate etiologies. 相似文献
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Shekarriz B Upadhyay J Wood DP Hinman J Raasch J Cummings GD Grignon D Littrup PJ 《Urology》1999,54(6):1044-1048
Objectives. To assess the role of clinical parameters and pathologic stage in predicting a positive vesicourethral anastomosis (VUA) biopsy in patients with a rising prostate-specific antigen (PSA) level after radical prostatectomy.Methods. Forty-five patients were referred for a rising PSA level after radical prostatectomy. Transrectal ultrasound evaluation included visualization of the VUA and VUA quadrant biopsies. The rate of positive biopsies (per core and per patient) was correlated with race, PSA level, and the radical prostatectomy pathologic stage.Results. Overall, 53% of patients had a positive biopsy. In multivariate analysis, the dominant independent and synergistic clinical parameters determining positive biopsy rates were a PSA greater than 1 ng/mL at the time of biopsy and the pathologic stage (P = 0.04 and P = 0.02, respectively). Using a PSA cutoff point of 1.0 ng/mL, those patients with organ-confined disease and a PSA of 1.0 ng/mL or less showed no positive cancer cores (low-risk group). Conversely, 89% of patients with extraprostatic extension and a PSA greater than 1.0 ng/mL had a positive biopsy (P <0.01) (high-risk group). Patients with organ-confined disease and a PSA greater than 1.0 ng/mL or extraprostatic extension and a PSA 1.0 ng/mL or less (intermediate-risk group) had a significantly higher chance of having residual cancer than the low-risk group (P <0.025).Conclusions. The PSA level at the time of biopsy and the pathologic stage of the radical prostatectomy specimen were the strongest determinants of a positive biopsy. A combination of PSA and pathologic stage is useful for decisions regarding VUA biopsy. Patients with organ-confined disease and a PSA of 1.0 ng/mL or less do not appear to benefit from a VUA biopsy, and patients with extraprostatic extension and a PSA greater than 1.0 ng/mL have such a high probability (89%) of local recurrence at the VUA that biopsy may be unnecessary. It appears that VUA biopsy can be restricted to those patients with an intermediate risk (organ-confined disease with PSA greater than 1 ng/mL or extraprostatic extension with a PSA less than 1 ng/mL). 相似文献
57.
Although closed femoral osteotomy for shortening or correction of deformity is not a new procedure, its popularity apparently is increasing. We have encountered a serious "biological" complication that should be considered before this technique is selected. Two patients, a 12-year-old girl and an 18-year-old man, developed findings consistent with the fat embolism syndrome after closed femoral shortening. We suggest consideration of postoperative monitoring with pulse oximetry of patients undergoing this procedure. 相似文献
58.
Cawthorn M Cummings GS Walker JR Donatelli RA 《The Journal of orthopaedic and sports physical therapy》1991,14(2):75-81
The purpose of this study was to determine the ankle position at which the greatest peak torque occurs during isokinetic testing of inversion and eversion force. Testing of right foot invertors and evertors was performed at 10 degrees dorsiflexion, neutral dorsiflexion and plantarflexion, and 10 degrees plantarflexion on 25 untrained subjects with the MERAC isokinetic dynamometer. Subjects were retested to determine reliability. Results indicate that 10 degrees plantarflexion appears better than the other positions tested because reliability was highest and torque output was greatest at this position. Reliability was assessed with a Pearson product moment test and a paired comparisons test (p = .05). A randomized block design and a Scheffé post hoc test demonstrated that significant differences in peak torque of both invertor and evertor muscles were found between the three testing positions (p = .01). No significant difference in the invertor to evertor force ratio wits found between the three testing positions. J Orthop Sports Phys Ther 1991;14(2):75-81. 相似文献
59.
F J Cummings C H Park H A Bogaars A E Kalderon I Melnicoff S R Kaplan I Diamond P Calabresi 《Medical and pediatric oncology》1979,7(2):181-190
Successful therapy for a case of multiple myeloma with a spontaneously crystallizing cryoglobulin of the IgG2-kappa light chain variety was achieved, using both continuous-flow cell centrifugation plasmapheresis to rapidly lower the M component and combination chemotherapy with phenylalanine mustard, prednisone, procarbazine, and vincristine to control the myeloma process. This resulted in resolution of incapacitating large and small necrotic cutaneous ulcerations of the extremities. Physicochemical studies of the crystalcryoprotein demonstrated that cryoprecipitation was rapid and accompanied by the formation of needle-shaped crystals, yet was completely reversible at 37 degrees C. Cryocrit determinations varied depending upon relative centrifugal forces and temperature and did not always relate linearly to the amount of abnormal protein, thus making these alone unreliable in assessing response to therapy. 相似文献
60.