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91.
M F Zeitlin R Megawangi E M Kramer H C Armstrong 《The American journal of clinical nutrition》1992,56(1):136-147
The vitamin A intake of 370 mothers and 183 children 3-27 mo of age in rural Bangladesh was ascertained monthly from January to July in 1986. For mothers, dark green leafy vegetables and fruits were the main sources of vitamin A. Vitamin A from vegetables, the single most important source, did not show consistent associations with wealth or with the other socioeconomic indicators. In May and June, fruits provided wealthier (and more educated) mothers with significantly higher vitamin A intakes than poor mothers, whereas in January the poorer mothers had higher intakes. When breast milk was included, average intakes for children came close to 100% of the recommended dietary allowance; the only other significant source of vitamin A for children was seasonally available mangoes. Fourteen children who had stopped breast-feeding by the end of the study were at very high risk of vitamin A deficiency when fruits were not plentiful. 相似文献
92.
The indications for elective treatment of the neck in cancer of the major salivary glands. 总被引:8,自引:0,他引:8
J G Armstrong L B Harrison H T Thaler H Friedlander-Klar D E Fass M J Zelefsky J P Shah E W Strong R H Spiro 《Cancer》1992,69(3):615-619
To define the indications for elective neck treatment, the cases of 474 previously untreated patients were reviewed who had locally confined major salivary gland cancers treated between 1939 and 1982. Clinically positive nodes were present in 14% (67 of 474). Overall, clinically occult, pathologically positive nodes occurred in 12% (47 of 407). By univariate analysis, several factors appeared to predict the risk of occult metastases; however, multivariate analysis revealed that only size and grade were significant risk factors. Tumors 4 cm or more in size had a 20% (32 of 164) risk of occult metastases compared with a 4% (nine of 220) risk for smaller tumors (P less than 0.00001). High-grade tumors (regardless of histologic type) had a 49% (29 of 59) risk of occult metastases compared with a 7% (15 of 221) risk for intermediate-grade or low-grade tumors (P less than 0.00001). In view of the low frequency of occult metastases in the entire group, routine elective treatment of the neck is not recommended. High-grade tumors and larger tumors have a high rate of occult neck metastases, and treatment should be considered in this group. 相似文献
93.
Pallav J Shah Manoj Durairaj Ian Gordon John Fuller Alex Rosalion Siven Seevanayagam James Tatoulis Brian F Buxton 《European journal of cardio-thoracic surgery》2004,26(1):118-124
OBJECTIVE: The purpose is to define factors influencing long-term patency of the internal thoracic artery (ITA) to optimize the operative strategy. METHODS: 1482 left internal thoracic artery (LITA) and 636 right internal thoracic artery (RITA) symptom-directed angiograms were studied in 1434 patients. Data were prospectively collected from patients who had primary coronary artery bypass surgery during the period 1982-2002. The mean age of patients was 59 years; 85% were male. The mean period from operation to re-angiogram was 80 months. LITA was grafted to left anterior descending coronary artery (LAD) in 82% of cases, RITA to right coronary artery (RCA) in 40% and circumflex artery in 35% of cases. Graft failure was defined as > or =80% stenosis. RESULTS: 96.3% of LITA and 88.1% of RITA grafts were patent. No patient variables were significantly associated with graft patency (age, gender, diabetes, hypertension, LVEF, NYHA, AMI). Target coronary artery was associated with patency of both LITA and RITA grafts with maximum patency when grafted to LAD (P = 0.02) RITA had the worst patency to RCA, patency for the left system was identical to LITA. Proximal anastomosis to aorta (free RITA) had significantly better patency when compared with in situ RITA to RCA system (P = 0.005) while similar patency when grafted to left system. ITA diameter and target artery diameter were not associated with graft patency. Recent operations had better RITA patency (P = 0.03). The interval from operation to angiogram was not associated with ITA patency (96% patency for LITA and 88% patency for RITA, remained stable when studied at <1, 1-4, 5-9, 10-14 and >15 years). CONCLUSIONS: Even in a patient cohort that had adverse symptoms, excellent LITA and RITA patency was achieved which almost remained constant through all time intervals studied. 相似文献
94.
95.
96.
Gordon Winocur Fergus I M Craik Brian Levine Ian H Robertson Malcolm A Binns Michael Alexander Sandra Black Deirdre Dawson Heather Palmer Tara McHugh Donald T Stuss 《Journal of the International Neuropsychological Society》2007,13(1):166-171
This study provides an overview of the papers emanating from the experimental trial that evaluated a new cognitive rehabilitation program in older adults who were experiencing normal cognitive decline. The main features of the design are summarized, along with evidence that the training produced long-lasting improvement in memory performance, goal management, and psychosocial status. The benefits were attributed to several factors, including the program's emphasis on techniques that promoted efficient strategic processing. Limitations of the program and directions for future research are discussed. 相似文献
97.
Analysis of in vivo short TE 1H spectra is complicated by broad baseline signal contributions and resonance line-shape distortions. Although the assumptions of ideal metabolite resonance line-shapes and slowly varying baseline signals can be used to separate these signals, the presence of broad or asymmetric line-shapes can invalidate this model. More complex line-shape models are computationally expensive or difficult to constrain, particularly for the low signal-to-noise commonly found for in vivo MR spectroscopic imaging applications. In this study, two time-domain models for fitting variable spectral line-shapes are examined, one using B-splines and another using summed sinusoids. The methods were verified using both phantom and human data, and Monte Carlo simulations were used to evaluate variations in calculated metabolite amplitudes due to interactions between the baseline and line-shape estimations. Additional studies investigated the use of prior line-shape information, obtained from either a water MRSI measurement or calculations from B(0) maps, to determine parameter starting values or optimization constraints. Both line-shape models showed the ability to fit the variety of line-shapes present in both the phantom and human MRSI data, with similar or improved accuracy over a Gaussian line-shape model; however, this improvement resulted in only minor improvement for the high-SNR phantom data and moderate improvements in regions with asymmetry for the fitted in vivo metabolite images. The use of prior line-shape information was of most benefit when applied toward setting optimization constraints but was of limited benefit when used to define initial starting values. 相似文献
98.
99.
H Dexter Barber John Lignelli Brian M Smith Barry K Bartee 《Journal of oral and maxillofacial surgery》2007,65(4):748-752
The most common types of barrier membranes used for bone or tissue regeneration are made of expanded-polytetrafluoroethylene (e-PTFE) or resorbable materials, such as collagen. Both the e-PTFE and resorbable membranes require primary soft tissue coverage. This article explores the use of a dense-polytetrafluoroethylene (d-PTFE) membrane, which does not require primary soft tissue coverage. The advantages of d-PTFE in contrast to the other more commonly used types of barrier membranes and the clinical significance of these advantages for implant surgical and restorative treatment are discussed. 相似文献
100.
N-acetylcysteine does not modify nitroglycerin-induced tolerance in canine vascular rings 总被引:2,自引:0,他引:2
The mechanism whereby nitroglycerin initiates relaxation in vascular smooth muscle remains unclear. One hypothesis states that nitroglycerin oxidizes critical sulfhydryl groups in smooth muscle to initiate relaxation, and that repeated exposure to nitroglycerin results in tolerance. In the current study, N-acetylcysteine, a sulfhydryl-reducing agent, was used to explore the sulfhydryl hypothesis by assessing whether or not tolerance to nitroglycerin was reversed by N-acetylcysteine in canine dorsal pedal artery rings. Two nitroglycerin dose-response curves were performed (n = 18)--one before (1st dose-response curve, from 10(-9) to 1.1 X 10(-5) M nitroglycerin) and one after (2nd dose-response curve, from 10(-9) to 5 X 10(-7) M nitroglycerin) incubation with 10(-5) M nitroglycerin for 105 min. At 5 X 10(-7) M nitroglycerin there was 50.7 +/- 10.0% relaxation during the first dose-response curve. During the second dose-response curve, tolerance to nitroglycerin was evident, as demonstrated by a 6.8 +/- 4.8% relaxation (p less than 0.001) at 5 X 10(-7) M nitroglycerin. A 10-min treatment with 10(-3) M N-acetylcysteine (n = 10) during the second nitroglycerin dose-response curve was performed after the 5 X 10(-7) M concentration of nitroglycerin; the second dose-response curve was then completed up to 1.1 X 10(-5) M nitroglycerin. The dose of 10(-3) M N-acetylcysteine was chosen since higher concentrations (i.e., 1.3 X 10(-2) and 1.2 X 10(-1) M N-acetylcysteine) produced 20.3 +/- 8.4 and 43.6 +/- 11.6% relaxation in vascular rings (n = 5).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献