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101.
FB Hu MJ Stampfer JE Manson EB Rimm GA Colditz BA Rosner FE Speizer CH Hennekens WC Willett 《Canadian Metallurgical Quarterly》1998,317(7169):1341-1345
OBJECTIVE: To examine the relation between nut consumption and risk of coronary heart disease in a cohort of women from the Nurses' Health Study. DESIGN: Prospective cohort study. SETTING: Nurses' Health Study. SUBJECTS: 86 016 women from 34 to 59 years of age without previously diagnosed coronary heart disease, stroke, or cancer at baseline in 1980. MAIN OUTCOME MEASURES: Major coronary heart disease including non-fatal myocardial infarction and fatal coronary heart disease. RESULTS: 1255 major coronary disease events (861 cases of non-fatal myocardial infarction and 394 cases of fatal coronary heart disease) occurred during 14 years of follow up. After adjusting for age, smoking, and other known risk factors for coronary heart disease, women who ate more than five units of nuts (one unit equivalent to 1 oz of nuts) a week (frequent consumption) had a significantly lower risk of total coronary heart disease (relative risk 0.65, 95% confidence interval 0.47 to 0.89, P for trend=0.0009) than women who never ate nuts or who ate less than one unit a month (rare consumption). The magnitude of risk reduction was similar for both fatal coronary heart disease (0.61, 0.35 to 1.05, P for trend=0.007) and non-fatal myocardial infarction (0.68, 0.47 to 1.00, P for trend=0.04). Further adjustment for intakes of dietary fats, fibre, vegetables, and fruits did not alter these results. The inverse association persisted in subgroups stratified by levels of smoking,use of alcohol, use of multivitamin and vitamin E supplements, body mass index, exercise, and intake of vegetables or fruits. CONCLUSIONS: Frequent nut consumption was associated with a reduced risk of both fatal coronary heart disease and non-fatal myocardial infarction. These data, and those from other epidemiological and clinical studies, support a role for nuts in reducing the risk of coronary heart disease. 相似文献
102.
Kovacic S.J. Robinson B.J. Simmons J.G. Thompson D.A. 《Electron Device Letters, IEEE》1993,14(2):54-56
The double-heterostructure optoelectronic switch (DOES), fabricated in the InP/InGaAsP material system, is demonstrated. The functional characteristics and operational parameters exhibit a lower switching voltage (≈1.8 V) and a higher on-state holding current (≈20 mA) than found in either the Si/SiGe- or GaAs/AlGaAs-based DOES of comparable structures and doping levels. In the on-state, optical emission is observed in a manner analogous to a light emitting diode. However, enhanced optical emission is observed when the device is biased in the regime of negative differential resistance 相似文献
103.
We observe deviations in the cyclotron effective mass mc near the partial energy gap formed in strongly coupled GaAs double quantum wells (QWs) subject to in-plane magnetic fields B. In k-space, B shifts the two QW dispersion curves relative to one another, resulting in an anticrossing and opening the energy gap. This gives rise to large B-tunable distortions in the Fermi surface and density of states. This system is thus unique in that the Fermi surface and energy position of the gap can be controlled by sweeping B. Recently, Lyo has predicted that mc undergoes large variations as the partial energy gap is moved through the Fermi level by B. By tilting our sample by a small angle θ, we introduce a small perpendicular magnetic field B, in addition to B, and analyze the temperature dependence of the resulting Shubnikov-de Haas oscillations to obtain mc(B). Due to the strongly distorted dispersion near the gap, mc is suppressed by more than a factor of 3 near the upper gap edge, and enhanced by 50% near the lower gap edge, in excellent agreement with the theory of Lyo. We also observe the quantum Hall effect in a double QW at a high, constant B. 相似文献
104.
Y Yamamoto DG Piepgras WR Marsh FB Meyer 《Canadian Metallurgical Quarterly》1996,39(4):670-5; discussion 675-6
OBJECTIVE: Reducing surgical risks to the minimum in carotid endarterectomy has become crucial, especially with the results of recent clinical trials extending indications to asymptomatic patients. The use of the saphenous vein patch graft (SVPG) has been suggested to reduce early postoperative thrombosis and cerebral infarct as well as late recurrent stenosis. However, the exact risks and complications involved in this technique are not known. METHODS: During a 23-year period (1972-1994), 2888 carotid endarterectomies with SVPG for primary carotid stenosis were performed by the Neurosurgical Cerebrovascular Service at the Mayo Clinic. The data from all patients were retrospectively analyzed, emphasizing postoperative complications related to SVPG. RESULTS: There were five postoperative vein ruptures (0.17%), four cases of aneurysm formation, and three cases of deep infection necessitating surgical intervention. The vein patch ruptured in one male patient and four female patients (mean age, 69 yr). All ruptures occurred within 4 days of the primary operation, including two during the first 24 hours. All patients with rupture underwent emergency surgery and were found to have intact suture lines and tears in the middle of the grafts. Two patients recovered without deficits, one suffered major disability, and the other two died. Aneurysm of the patch developed in two male patients and two female patients (mean age, 71 yr). All of the patients developed painless pulsatile neck masses 1 to 9 years after the initial surgery; two also had recurrent ischemic symptoms. All of the patients with aneurysms underwent surgical correction without consequences. CONCLUSION: Although the benefit of routine use of SVPG in carotid endarterectomy is still the focus of debate, this analysis showed that its use adds a small but definite risk of serious complications related to inherent weakness of the venous tissue. If a surgeon chooses to use a patch graft, our recommendation is for use of a synthetic material rather than vein. 相似文献
105.
106.
MK Sly MD Prager J Li FB Harris P Shastri R Bhujle R Chao PV Kulkarni A Constantinescu ME Jessen RC Eberhart 《Canadian Metallurgical Quarterly》1996,42(5):M494-M499
The authors used quantitative gamma scintigraphy to evaluate the influence of nitric oxide gas on platelet and neutrophil deposition in Cobe Duo microporous oxygenators during cardiopulmonary bypass (CPB). The effects of nitric oxide gas on circulating platelet and neutrophil counts and platelet function also were assessed. Animals were prepared by standard methods. Cells were harvested, labeled (111 In platelet and 99mTc neutrophil), infused, and recirculated. Nitric oxide gas, a guanylate cyclase pathway promoter, was infused int he Duo gas port at 500 ppm (t = 0-60 min), increased to 1,000 (t = 60-80 min), and stopped (final, 10 min). Images were taken at 10-15 min intervals during CPB. Standard isotope image corrections were made. No differences between nitric oxide gas and control experiments were observed for flow, pressure, hematocrit, or replacement volume. Nitric oxide gas infusion significantly (p < 0.05) reduced both platelet adherence to the oxygenator and in vitro platelet aggregation. Neutrophil adhesion tended to be lower, and circulating platelet and neutrophil counts tended to be higher with nitric oxide gas infusion. Results of in vitro aggregometry studies using rabbit platelets indicate that the class V phosphodiesterase inhibitor zaprinast can strongly enhance the inhibitory effects of nitric oxide. The authors conclude nitric oxide gas is a promising platelet sparing agent in the setting of CPB. 相似文献
107.
RJ Howard DH ffytche J Barnes D McKeefry Y Ha PW Woodruff ET Bullmore A Simmons SC Williams AS David M Brammer 《Canadian Metallurgical Quarterly》1998,9(6):1019-1023
OBJECTIVE: To determine whether the progression of urinary albumin excretion rate (AER) is higher during puberty than before or after this period. RESEARCH DESIGN AND METHODS: A prospective study was conducted in which normoalbuminuric prepubertal (n = 20), pubertal (n = 28), and postpubertal (n = 26) IDDM groups matched for diabetes duration and long-term metabolic control were followed for 3 years. At 6-month intervals, 24-h urine collection was used to determine AER. RESULTS: AER increased significantly over a period of 3 years in the pubertal (P = 0.001) and postpubertal (P = 0.003) subjects but not in prepubertal subjects. The annual progression of AER was significantly higher in the pubertal group than in the prepubertal (P = 0.001) or postpubertal (P = 0.001) groups. Six pubertal, two postpubertal, and none of the prepubertal subjects developed microalbuminuria (AER > or = 20 micrograms/min on two consecutive occasions) over a 3-year period (P = 0.047). Multiple logistic regression analysis showed that the risk of development of microalbuminuria was increased in pubertal subjects compared with the prepubertal and postpubertal subjects (adjusted relative risk [95% CI]: 4.3 [1.5-9.3], P = 0.012, and 2.1 [1.1-5.0], P = 0.023, respectively). CONCLUSIONS: Puberty represents an independent risk of the development of microalbuminuria in diabetes. This findings suggests that the endocrine changes of puberty lead to an accelerated process of early kidney damage in diabetes. In pediatric diabetes care, screening for microalbuminuria is needed soon after the onset of puberty. 相似文献
108.
AM Rauck FB Ruymann K Klopfenstein N Grossman R Rosselet L Grovas S Ceselski J Hayes AC Grovas 《Canadian Metallurgical Quarterly》1998,13(4):146-154
PURPOSE: Peripheral blood stem cell (PBSC) apheresis provides an alternative to autologous marrow harvest as a source of hematologic stem cells for transplantation in children with solid tumors. PATIENTS AND METHODS: Eight children with metastatic or recurrent solid tumors underwent 27 apheresis procedures. Recovery from myelosuppressive chemotherapy occurred without continuous daily growth factor support prior to mobilization. Granulocyte colony stimulating factor (G-CSF) at 16 microgs/kg/day was used to increase stem cells in the peripheral circulation. CD 34 positive cells, mononuclear cells (MNC), and CFU-GM were measured in the apheresis products. Prior chemotherapy was examined as a clinical factor that affected PBSC yield. RESULTS: A significant correlation was found between CD 34+/kg and CFU-GM/kg of the products (r = 0.758, P < 0.001). Patients receiving cumulative doses of carboplatin over 1,600 mg/m2 produced adequate MNC (1 x 10(8)/kg) but yielded significantly less CD 34+ cells or CFU-GM than those patients receiving less carboplatin. Prior doses of etoposide and ifosfamide did not effect PBSC yield. CONCLUSIONS: The mobilization technique was well tolerated, and the products obtained produced trilineage engraftment in the patients that underwent peripheral blood stem cell transplantation. Peripheral blood stem cell apheresis in children can be optimized by selection of appropriate candidates and mobilization with G-CSF after an absence of hematopoietic growth factor support. 相似文献
109.
110.
S Dusi KA Nadalini M Donini L Zentilin FB Wientjes D Roos M Giacca F Rossi 《Canadian Metallurgical Quarterly》1998,161(9):4968-4974
This paper deals with the mechanisms of activation of NADPH oxidase investigated using EBV-transformed human B lymphoblastoid cell lines (B cells) from normal subjects and from patients affected by X-linked chronic granulomatous disease (CGD). The results reported are as follows. 1) In normal B cells, the NADPH oxidase components p67phox, p40phox, p22phox, and gp91phox were less expressed than in polymorphonuclear neutrophils. 2) In normal B cells stimulated with PMA, p47phox, p67phox, and p40phox translocated to the membranes as occurs in polymorphonuclear neutrophils. 3) In CGD, B cells expressing p22phox in the absence of gp91phox, p47phox, p67phox, and p40phox did not translocate to the membranes after stimulation with PMA. 4) In PMA-stimulated B cells from an X91+ CGD patient in which p22phox was normally expressed and gp91phox was present but lacked five amino acids, translocation of p47phox to the membranes was unaffected, but p67phox and p40phox were poorly translocated, and the production of O2- was greatly reduced with respect to that by normal B cells. Taken together, these findings indicate that 1) a low expression of some NADPH oxidase components may represent the molecular basis of the low production of O2- in B lymphocytes; 2) the cytosolic components of NADPH oxidase cannot bind to p22phox on the membranes in the absence of gp91phox; 3) p47phox can translocate to the membranes independently of p67phox and p40phox; and 4) gp91phox may have a role in mediating and/or stabilizing the binding of p67phox and p40phox to the membranes of activated cells. 相似文献