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91.
92.
Evaluating food fortification options: general principles revisited with folic acid. 总被引:6,自引:3,他引:3 下载免费PDF全文
N T Crane D B Wilson D A Cook C J Lewis E A Yetley J I Rader 《American journal of public health》1995,85(5):660-666
OBJECTIVES. This article uses folic acid as an example to illustrate some of the complex issues and general principles that emerge when evaluating fortification of the food supply as one possible means to address a public health recommendation. METHODS. Distributions of current daily folate intakes from conventional foods and dietary supplements were estimated. Intakes that might result from fortification of cereal-grain products and ready-to-eat cereals at various levels for eight age-gender groups were also estimated by using the US Department of Agriculture's 1987-1988 Nationwide Food Consumption Survey. RESULTS. The results illustrate that fortification of the US food supply tends to increase folate intakes of consumers at the high end of the intake distribution curves in the general population to a greater extent than it affects consumers at the low end of the intake distribution curves in the target population. CONCLUSIONS. The effectiveness of food fortification options for a target population and the safety for the general population impose conflicting challenges that must be considered concurrently when making decisions about fortifying the US food supply. 相似文献
93.
Nonfatal childhood injuries: a survey at the Children's Hospital of eastern Ontario. 总被引:7,自引:0,他引:7 下载免费PDF全文
OBJECTIVE: To examine the types and severity of injuries seen in the Emergency Department of the Children's Hospital of Eastern Ontario and the circumstances surrounding the events. DESIGN: Chart review. SETTING: A tertiary care hospital that serves a child population of 600,000 in eastern Ontario and western Quebec. PARTICIPANTS: Every sixth day's charts of children up to 17 years of age who visited the Emergency Department because of injuries between Sept. 1, 1984, and Aug. 31, 1985, were examined retrospectively. RESULTS: A total of 2886 charts were reviewed. There were more boys than girls. Most (1354 [46.9%]) of the accidents had occurred at home. Falls and sports-related accidents were the leading causes of injury (in 1088 [37.7%] and 560 [19.4%] of the cases respectively). Most of the visits were for minor injuries (bumps, swellings, cuts, bruises and scrapes), and only 114 (4.0%) of the children were admitted to the hospital. Injuries from motor vehicle accidents accounted for the highest admission rate (17.4%). Important information regarding the circumstances surrounding the events (e.g., whether a seat belt or car seat was used) was frequently missing from the charts. CONCLUSIONS: Nonfatal injuries are common, especially in or around the home, and remain a significant problem in our society in terms of radiographic and consulting fees, time off from school or work and pain. Given the difficulties in obtaining information on the circumstances surrounding the events prospective studies are needed. Factors related to the occurrence and severity of childhood injury and whether these factors can be altered remain a high priority for research. 相似文献
94.
95.
Tunnelled silicone rubber right atrial catheters are commonly used to administer long-term total parenteral nutrition (TPN), cancer chemotherapeutic agents, and antimicrobial agents. The indwelling devices potentiate platelet-fibrin thrombi formation, providing a nidus for infection. Although many episodes of sepsis associated with thrombotic tunnelled catheters respond to antimicrobial therapy alone, a significant number require catheter removal. Evidence from case studies and small clinical trials suggests that fibrinolytic agents may increase the response rate and prevent removal of the device when combined with antimicrobial therapy. We present the first case reported of bacterial sepsis secondary to a thrombotic indwelling Hickman catheter for long-term TPN successfully treated with a combination of streptokinase and antibiotic therapies. 相似文献
96.
97.
Anne M Lewis Sheelu Varghese Hui Xu H Richard Alexander 《Journal of translational medicine》2006,4(1):48
The tumor microenvironment consists of tumor, immune, stromal, and inflammatory cells which produce cytokines, growth factors,
and adhesion molecules that promote tumor progression and metastasis. Of particular interest in this setting is interleukin-1
(IL-1), a pleiotropic cytokine with numerous roles in both physiological and pathological states. It is known to be up regulated
in many tumor types and has been implicated as a factor in tumor progression via the expression of metastatic and angiogenic
genes and growth factors. A number of studies have reported that high IL-1 concentrations within the tumor microenvironment
are associated with a more virulent tumor phenotype. Solid tumors in which IL-1 has been shown to be up regulated include
breast, colon, lung, head and neck cancers, and melanomas, and patients with IL-1 producing tumors have generally bad prognoses.
The exact mechanisms by which IL-1 promotes tumor growth remain unclear, though the protein is believed to act via induction
of pro-metastatic genes such as matrix metalloproteinases and through the stimulation of adjacent cells to produce angiogenic
proteins and growth factors such as VEGF, IL-8, IL-6, TNFα, and TGFβ. The IL-1 receptor antagonist (IL-1ra) is a naturally
occurring inhibitor to IL-1 and acts by binding to the IL-1 receptor without activating it. The protein has been shown to
decrease tumor growth, angiogenesis, and metastases in murine xenograft models. Our focus in this review is to summarize the
known data on the role of IL-1 in tumor progression and metastasis and the use of IL-1 inhibition as a novel therapeutic approach
in the treatment of solid organ malignancies. 相似文献
98.
G van Servellen C E Lewis B Leake S O Schweitzer 《The Journal of the Association of Nurses in AIDS Care》1991,2(3):29-39
The authors assessed patients' satisfaction with their nursing care in seven hospitals. Five of the hospitals utilized the special care unit (SCU) method of delivering care to AIDS or oncology patients; three had SCUs for AIDS patients. All seven of the hospitals had integrated units (IUs) where general medical, oncology, and/or AIDS patients were received in various proportions. Satisfaction with nursing care was measured with the Risser Patient Satisfaction Instrument. Patient satisfaction with nursing care was shown to be a function of delivery method; AIDS and oncology patients on SCUs expressed greater satisfaction with their care than medical, oncology, or AIDS patients on IUs (p less than .001). Patient satisfaction with nursing care was greater among whites than nonwhites. Also, some major sociodemographic and case mix variables, such as age, employment status, and diagnosis, were not associated with patient satisfaction directly; in other instances, the associations initially seen did not hold when delivery method (SCU vs. IU) and race were controlled for in a linear regression analysis. 相似文献
99.
Factors associated with hypertension in Nigerian civil servants 总被引:3,自引:0,他引:3
Clareann H. Bunker Ph.D. Flora A. Ukoli M.B.B.S. Martin U. Nwankwo M.B.B.S. Jackson A. Omene M.D. Glenn W. Currier M.D. Linda Holifield-Kennedy Donald T. Freeman Emanuel N. Vergis M.D. Lan Lan L. Yeh Ph.D. Lewis H. Kuller M.D. Dr.P.H. 《Preventive medicine》1992,21(6):710-722
BACKGROUND. Study of hypertension in segments of West African populations in transition toward Westernization may lead to better understanding of the high risk for hypertension among Westernized blacks. METHODS. Five hundred fifty-nine urban civil servants, ages 25-54, were recruited from six ministries of Bendel State, Nigeria. Blood pressure, physical measurements, urinary protein and glucose, fasting blood glucose, and demographic data were collected at the workplace. Subjects were classified as senior staff (professionals or administrators) or junior staff (non-administrators). RESULTS. Among 172 male senior staff, the age-adjusted rate of hypertension (diastolic blood pressure > or = 90 mm Hg, systolic blood pressure > or = 140 mm Hg, or on an antihypertensive medication) was 43% and occurrence rose dramatically from 21 to 63% across age groups 25-34 to 45-54, respectively. Among 266 male junior staff, the age-adjusted rate of hypertension was 23%, and occurrence did not rise with age. Logistic regression showed that body mass index (kg/m2), age, alcohol drinking, and being senior staff were all independently related to hypertension in men. On the other hand, the age-adjusted rate of hypertension in 121 women was 20% and was significantly related only to body mass index. CONCLUSION. Male urban civil servants appeared to have a risk for hypertension similar to that of U.S. black males. Age, body mass index, alcohol drinking, and other unidentified factors related to higher socioeconomic status were strong determinants of hypertension in this population. 相似文献
100.
In this study, the cost and health outcomes of a psychiatric consultation letter to primary care physicians caring for a sample of patients diagnosed with somatization disorder, a psychiatric condition associated with multiple, unexplained medical complaints, was assessed. To accommodate the small sample size of 73 patients, outcome effects were calculated using panel analysis. Study patients were randomized to a consultation or noconsultation group, and were repeatedly assessed at equal time intervals. Data were analyzed using parsimonious regression models derived from economic theory. During the 1-year follow-up period, a psychiatric consultation letter was associated with a 12% reduction in health care costs ($455 per patient within first year), with no evidence of deterioration in physical, mental, or general health. Less powerful t-test comparisons between treated and control groups lead to different conclusions. Reasons for these differences are discussed. 相似文献