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71.
72.
The iron status of a national sample of adults living in France and participating in the SU.VI.MAX cohort, was assessed using serum ferritin and hemoglobin concentrations. Complete data were obtained for 6648 women 35-60 y old and for 3283 men 45-60 y old. Assessment of iron dietary intakes was realized on a subsample of 3111 women and 2337 men who reported six 24 h dietary records during a one-year period; 22.7% of menstruating women and 5.3% of post-menopausal women presented a total depletion of iron stores (serum ferritin < 15 microg/l). Iron-deficient anemias were found in, respectively, 4.4% and less than 1% of these women. Three-quarters of the anemias were related to iron deficiency in menstruating women. In men, iron depletion and iron deficiency anemia were very rare. Post-menopausal women had much higher serum ferritin levels than menstruating women. In menstruating women, those using intrauterine devices had significantly lower serum ferritin levels than those without contraception, and much lower than those using oral contraception. The frequency of iron depletion reached 28.1% in women using intrauterine devices, but only 13.6% in those using oral contraceptives. The mean iron intake was 16.7 +/- 5.7 mg/d in men and 12.3 +/- 3.4 mg/d in women. Heme iron represented respectively, 11.1 and 10.4% of iron intake. Ninety-three percent of menstruating women had dietary iron intakes lower than recommended dietary allowances (RDA); 52.6% consumed less than two thirds of these RDA. In post-menopausal women and men, respectively 27.7% and 3.6% had dietary intakes lower than RDA. Serum ferritin was positively correlated with meat, fish and total iron intake, and negatively correlated with dietary products consumption, calcium and fiber intake.  相似文献   
73.
Vacuum transient pulse and continuous flow investigations on the ammoxidation of propane over VSbxOy (x = 1, 2 and 5) and (VO)2P2O7 catalysts reveal that propene and acrolein are reaction intermediates over both types of oxides. However, the N-insertion step and the formation of total oxidation products proceed significantly different. Short-lived NH3 or NH4 + species are involved in the N-insertion step over V-Sb-O, whereas strongly bound, long-lived NHx species are participating in the reaction on V-P-O. Only lattice oxygen is involved in the hydrocarbon reaction pathway over V-Sb-O, whereas additionally adsorbed oxygen species lead to total oxidation over V-P-O. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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75.
K. Buchholz 《Scientometrics》1995,32(2):195-218
One of the major questions in science research is addressed in detail, that is the problem of evaluation of research work both by objective characterization, accessible to proof, and by adequate characterization, referring to the content and cognitive level of the work under investigation. A short discussion of established methods by science indicators as well as by peer review compiles merits and shortcomings of these methods. A short review refers to a few approaches towards the development of criteria for an improved assessment and characterization of research work and their shortcomings are discussed. Notably for the evaluation of medium or low range quality no reliable method is available. Therefore a systematic compilation of criteria which covers the full range of excellence to failure with respect to scientific quality is developed and a comprehensive list of criteria is presented which should provide a basis both for objective and adequate characterization of publications.  相似文献   
76.
Responds to the article by L. S. Brown (see record 84-21642) regarding managed care and false memory movement issues in social justice-oriented psychology. The current author argues that Brown abandoned psychologists be declining to think through how responsible and ethical people can work their way out of binds. Buchholz also contends that a greater call to unity and action among psychologists is needed to fight the dehumanizing and threatening effects of the HMOs and insurance companies on mental health service delivery. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
77.
Epidermal growth factor receptor (EGF-r) expression and tumor cell proliferation rate have been proposed as potential prognostic parameters in renal cell carcinoma (RCC). In this study, immunohistochemical stains using antibodies to EGF-r and the cell proliferation marker Ki-67 (MIB-1) were used to study the relationship between EGF-r expression, tumor cell proliferation, and prognosis in 50 non-papillary RCC extending beyond the renal capsule (pT3). A high Ki-67 labeling index (LI) was associated with poor patient prognosis (P < .05). Thirty-eight cases (76%) expressed strong cell membrane immunoreactivity for EGF-r. There was a tendency toward a shortened survival for EGF-r-positive tumors (P = .08). Tumor growth fraction (Ki-67 LI) was significantly higher in EGF-r-positive tumors than in EGF-r-negative tumors (P < .05), suggesting that rapid tumor proliferation might be responsible for the poor prognosis associated with EGF-r-positive RCC.  相似文献   
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79.
This paper reviews some of the difficulties encountered in achieving a uniform stress distribution within the adhesive layer of bonded Iosipescu shear test specimens. The asymptotic singular stress field at the terminus of a skewed bimaterial interface, intersecting the straight free surface of the wedge, has been studied macroscopically and microscopically using the finite element method (FEM) and the finite element iterative method (FEIM). Different mechanical properties of the adhesives and adherends, and various skewed interface angles have been considered in this study. A critical skewed interface angle, c=126°, has been found beyond which the interfacial stress singularity vanishes. This critical angle is independent of the elastic properties of the adhesives and adherends. Based on the results obtained in the present investigation, in conjunction with recently reported research on sharp notches [7, 21–23], an optimized adhesive joint Iosipescu specimen geometry is proposed. This specimen should be capable of generating a uniform shear stress state within its adhesive layer under pure shear loading conditions.  相似文献   
80.
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