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71.
72.
Objectives: While the importance of exploring and better measuring elements of prenatal care have been noted in the public health literature, the components and timing of such services have been poorly examined for the overall pregnant population and specifically for African-Americans, who traditionally have had higher rates of low birth weight and premature delivery. This study explores the association between patient receipt of selected recommended prenatal care interventions and infant birth weight in a nationally representative sample of African-American women, while controlling for the influence of low birth weight risk indicators. Method: This is a retrospective case-control analysis using survey data of women who delivered normal birth weight, moderate low birth weight, and very low birth weight newborns in 1988. A sample of 3905 African-American women who responded to the 1988 National Maternal and Infant Health Survey is examined based on maternal recall of receipt of six clinical screening procedures and seven health-promotion recommendations. Birth weight measures were obtained from linked 1988 birth certificate data. Results: The initial results indicated that women who do not receive all of the recommended health-promotion advice are more likely to deliver very low birth weight infants than women who receive all of the advice in the content of their prenatal care, after controlling for low birth weight risks (OR = 1.28; 95% CI = 1.01, 1.7). However, when breast-feeding advice is removed from the aggregation of health-promotion advice, the significant effect of advice on very low birth weight is negated. No other significant group variations in the receipt of clinical screening procedures or health-promotion advice for women who gave birth in the remaining birth weight categories are observed. Conclusions: Nationally recommended initial clinical screening procedures and health-promotion advice in prenatal care content do not appear to be associated with a reduction in low birth weight for African-American women. More research is needed to better assess the impact of other antenatal interventions, particularly those given to women with a higher prevalence of poor birth outcomes. 相似文献
73.
Grummer-Strawn LM Rice SP Dugas K Clark LD Benton-Davis S 《Maternal and child health journal》1997,1(1):35-42
Objective: This study evaluates the effectiveness of a peer counseling program at increasing breastfeeding by participants in the Mississippi Special Supplemental Nutrition Program for Women, Infants and Children (WIC). Methods: Data from the 1989–1993 Pediatric Nutrition Surveillance System were analyzed to compare breastfeeding rates in clinics with and without peer counseling programs. A questionnaire completed by program staff to describe the program in greater detail helped identify characteristics associated with greater success. Results: The incidence of breastfeeding rose from 12.3% to 19.9% in those clinics with peer counseling programs, but only from 9.2% to 10.7% in clinics without a program. Clinics that started a program earlier showed greater changes in breastfeeding incidence. However, the presence of lactation specialists or consultants in the clinic appeared to be more important than the presence of less-trained peer counselors. Peer counselors who spent more than 45 minutes per participant were more effective than those spending less time. Conclusions: The peer counseling program significantly increased the incidence of breastfeeding, particularly in clinics with lactation specialists and consultants. Success can be enhanced by ensuring that peer counselors spend a great deal of time with the participants. 相似文献
74.
Nicklas TA Johnson CC Farris R Rice R Lyon L Shi R 《American journal of health promotion : AJHP》1997,11(5):315-322
PURPOSE: To describe a 4-year intervention targeting fruit/vegetable consumption by high school students. DESIGN: This is a cohort study involving six pairs of schools (n = 12) matched on gender, race, enrollment, and location with schools randomly assigned within pairs to intervention or control conditions. SETTING: Twelve Archdiocese of New Orleans high schools. SUBJECTS: Cohort was defined as students (n = 2339) who were ninth-graders in the 1993-94 school year who provided baseline data. INTERVENTION: Four components of the intervention are: (1) school-wide media-marketing campaign, (2) school-wide meal and snack modification, (3) classroom workshops and supplementary subject matter activities, and (4) parental involvement. MEASURES: Focus groups were conducted for target population input and program development. Process evaluation included student feedback on media-marketing intervention materials and activities reported here. Process measures also included school meal participation, student characteristics, and verification of intervention activities. RESULTS: Focus groups identified barriers to increased consumption of fruit and vegetables as lack of availability, variety, and inconsistency in taste. Student attitudes were favorable regarding a school program to improve diet and parental involvement. Low consumption of fruits/vegetables was reported. After a 2-month school-wide program introduction utilizing various media-marketing materials and activities, 93% of students were aware of the program and 96% could identify the healthy eating message. CONCLUSIONS: Program development can be guided and enriched by student input via focus groups. Media-marketing activities effectively delivered health messages and attracted students' attention. Materials and activities used were acceptable channels for increasing awareness, positive attitudes, and knowledge about fruits/vegetables. 相似文献
75.
We analyzed isolates of Escherichia coli O157:H7 (which has recently caused waterborne outbreaks) and wild-type E. coli to determine their sensitivity to chlorination. Both pathogenic and nonpathogenic strains were significantly reduced within 1 minute of exposure to free chlorine. Results indicate that chlorine levels typically maintained in water systems are sufficient to inactivate these organisms. 相似文献
76.
Rice GP 《BioDrugs : clinical immunotherapeutics, biopharmaceuticals and gene therapy》1999,12(4):267-277
Disease progression and advancing disability will supervene in the majority of multiple sclerosis patients who are followed over the long-term. This process can begin insidiously from the onset of the disease (primary progression) or after one or more clinical flares (secondary progression). The factors which lead to progression of disability are incompletely understood. The progressive forms of multiple sclerosis have been remarkably resistant to treatment. The legacy of heroic immunosuppression as a treatment for the disease progression has been modest indeed although there is some recent enthusiasm for immunosuppression with agents like mitoxantrone. In the last decade, the treatment of relapsing forms of multiple sclerosis has been revitalised by the interferons and glatiramer acetate. The robust treatment effect on the magnetic resonance imaging burden of the disease and the modest treatment effect in the suppression of clinical attacks have raised hopes that these agents might stall the disease in its progressive phase. Recent clinical trials with the interferons are indeed showing promise for modest clinical efficacy in patients selected for treatment on the basis of chronic progression. Given the weakness of the current treatment, the essence of disease management remains the handling of the complications of the disease. The management of bladder disturbances, spasticity, pain, depression, emotional lability, paroxysmal disorders, fatigue and heat intolerance, tremor and sexual dysfunction is reviewed. 相似文献
77.
Rice ME 《Neurotoxicity research》1999,1(2):81-90
Ascorbic acid, found physiologically as the ascorbate anion, is an abundant water-soluble antioxidant. It is concentrated in the intracellular compartment of all tissues in the body. The CNS has particularly high levels of ascorbate. Recent data from this laboratory indicate that ascorbate is distinctly compartmentalized between neurons and glia, with an average intracellular concentration of 10 mM in neurons and 1 mM in glial cells. These data can be contrasted with those for another important low molecular weight antioxidant, glutathione, which is somewhat more concentrated in glia than in neurons. The present review summarizes evidence for ascorbate compartmentalization between neurons and glia and considers these data in light of evidence for the roles of ascorbate as a neuroprotective antioxidant and as a neuromodulator in the CNS. 相似文献
78.
Xu H Lu YF Partilla JS Zheng QX Wang JB Brine GA Carroll FI Rice KC Chen KX Chi ZQ Rothman RB 《Synapse (New York, N.Y.)》1999,32(1):23-28
Previous data obtained with the cloned rat mu opioid receptor demonstrated that the "super-potent" opiates, ohmefentanyl (RTI-4614-4) and its four enantiomers, differ in binding affinity, potency, efficacy, and intrinsic efficacy. Molecular modeling (Tang et al., 1996) of fentanyl derivatives binding to the mu receptor suggests that Asp147, Tyr148, Trp318, and His319 are important residues for binding. According to this model, Asp147 interacts with the positively charged opiate agonist to form potent electrostatic and hydrogen-bonding interactions. In this study, the role of weak electrostatic and hydrogen-bonding "pi-pi" interactions of the O atom of the carbonyl group and the phenyl ring structures of RTI-4614-4 and its four enantiomers with residues Tyr148, Trp318, and His319 were explored via site-directed mutagenesis. Tyr148 (in transmembrane helix 3 {TMH3}), Trp318 (TMH7), and His319 (TMH7) were individually replaced with phenylalanine or alanine. Receptors transiently expressed in COS-7 cells were labeled with [125I]IOXY according to published procedures. Mutation of Tyr148 to phenylalanine reduced the binding affinities of some mu-selective agonists (2-7 fold) but did not alter the affinities of DAMGO, naloxone, and the non-selective opiates etorphine and buprenorphine. In contrast, this mutation significantly increased the binding affinities (decreased the Kd values) of [D-Ala2,D-Leu5]enkephalin, IOXY, and dermorphin. Mutation of Trp318 decreased opioid receptor binding to almost undetectable levels. Substitution of alanine for His319 significantly reduced binding affinities for the opioid ligands tested (1.3- to 48-fold), but did not alter the affinities of naloxone and bremazocine. These results indicate the importance of Tyrl48 and His319 for the binding of fentanyl derivatives to the mu receptor. Functional studies using the mutant receptors will provide additional insight into the mechanism of action of RTI-4614-4 and its four enantiomers. 相似文献
79.
Medicare expenditures attributable to smoking in 1993 were estimated using a multivariate model that related expenditures to smoking history, health status, and the propensity to have had a smoking-related disease, controlling for sociodemographics, economic variables, and other risk factors. Smoking-attributable Medicare expenditures are presented separately for each State and by type of expenditure. Nationally, smoking accounted for 9.4 percent of Medicare expenditures--$14.2 billion, with considerable variation among States. Smoking accounted for 11.4 percent of Medicare expenditures for hospital care, 11.3 percent of nursing home care, 5.9 percent of home health care, and 5.6 percent of ambulatory care. 相似文献
80.
T J Lentz C H Rice J E Lockey P A Succop G K Lemasters 《American journal of industrial medicine》1999,36(2):286-298
BACKGROUND: To determine dimensions of airborne fibers in the U.S. refractory ceramic fiber (RCF) manufacturing industry, fibers collected through personal air sampling for employees at RCF manufacturing and processing operations have been measured. METHODS: Data were derived from transmission electron microscopy analyses of 118 air samples collected over a 20-year period. RESULTS: Characteristics of sized fibers include: diameter measurements of <60; 0.19 to 1.0 micron, m of which 75% are less than 0.6 micron and length ranging from < 0.6 to > 20 micron, with 68% of fibers between 2.4 and 20 micron. CONCLUSIONS: Exposures in RCF manufacturing include airborne fibers with dimensions (diameter < 0.1-0.4 micron, length < 10 micron) historically associated with biological effects in pleural tissues. Air sampling data and a review of studies relating fiber size to pleural effects in animals and humans support the belief that information on fiber dimensions is essential for studies with synthetic vitreous fibers. 相似文献