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991.
We examined seven 1-d diet records kept during 1 y by 272 men and women instructed to follow a lipid-lowering diet while participating in a clinical trial of pravastatin, a new 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor. The mean percentage of calories from total fat and saturated, unsaturated, and monounsaturated fatty acids was similar throughout the year even though the patients knew they were taking an effective lipid-lowering agent. However, the diets of greater than 40% of women included less than two-thirds of the recommended dietary allowance (RDA) of folic acid, vitamins B-6 and D, and calcium and zinc; in men, folic acid and zinc intakes were low. We conclude that patients comply with lipid-lowering diets even when they know that they are receiving an effective serum lipid-lowering agent. However, for both men and women special attention should be given to the intake of several nutrients. 相似文献
992.
We investigated the effect of oral contraceptives with low and high estrogen concentration on blood coagulation and thrombogenesis, induced by vascular subendothelium of rabbit aorta exposed to flowing human blood. Twenty healthy women intending to take oral contraceptives were studied [1] before drug ingestion (control), and subsequently during the intake of oral contraceptives with [2] low estrogen content (20 micrograms ethinyl estradiol and 150 micrograms desogestrel per day) and [3] high estrogen content (50 micrograms ethinyl estradiol and 125 micrograms desogestrel per day). All experiments were performed between day 17 and 21 of the menstrual cycle and drug effects were studied during the third tablet cycle. Deposition of fibrin, platelets and platelet thrombi on vascular subendothelium was tested at a defined blood flow and wall shear rate (10 ml/min, 650 s-1) and was quantified by morphometrical techniques. Treatment with the low and high dose contraceptive increased the plasma levels of ethinyl estradiol (728 +/- 139 and 1438 +/- 212 vs. 0 fmol/l [low and high dose vs. control], means +/- SEM, P less than 0.001) and fibrinogen (2.3 +/- 0.1 and 2.6 +/- 0.1 vs. 2.0 +/- 0.1 g/l, P less than 0.05); and decreased antithrombin III activity (95 +/- 3 and 92 +/- 3 vs. 101 +/- 3 %, P less than 0.05). Fibrin deposition on vascular subendothelium was enhanced by the high dose contraceptive only (47 +/- 4 vs. 35 +/- 4 % coverage of the subendothelial surface with fibrin, high dose vs. control, P less than 0.05). The subendothelial deposition of platelets and platelet thrombi was not changed by contraceptive treatment. These results indicate that treatment with high dose contraceptives leads to an increase of fibrin-subendothelial interactions, whereas low dose contraceptives do not significantly alter the blood-subendothelium interactions. observed in this ex vivo model of thrombogenesis. 相似文献
993.
Human immunodeficiency virus infection in urban Rwanda. Demographic and behavioral correlates in a representative sample of childbearing women 总被引:9,自引:0,他引:9
S Allen C Lindan A Serufilira P Van de Perre A C Rundle F Nsengumuremyi M Carael J Schwalbe S Hulley 《JAMA》1991,266(12):1657-1663
OBJECTIVE.--To determine behavioral and demographic risk factors for human immunodeficiency virus (HIV) infection in central Africa. DESIGN.--Cross-sectional survey. SETTING.--Kigali, Rwanda. PARTICIPANTS.--A representative sample of 1458 childbearing women aged 19 to 37 years who were recruited from outpatient prenatal and pediatric clinics at the only community hospital in the city. MAIN OUTCOME MEASURE.--Antibodies to HIV assessed by enzyme immunoassay and confirmed by Western blot or indirect immunofluorescence. RESULTS.--The HIV seroprevalence was 32% overall. Infection rates were higher in women who were single, in those in steady relationships that began after 1981, and in the 33% of women reporting more than one lifetime sexual partner. Women in legal marriages or monogamous partnerships had lower rates of infection, but even low-risk women had prevalences on the order of 20%. History of venereal disease in the past 5 years, although the strongest risk factor in a multiple logistic analysis (odds ratio, 2.7; 95% confidence interval, 2.0 to 3.7), was reported by only 30% of those infected. Having a male sexual partner who drank alcohol or who had higher income were significant risk factors for HIV infection in the multivariate analysis, but use of oral contraceptives and having an uncircumcised partner were not. CONCLUSIONS.--The epidemic of the acquired immunodeficiency syndrome in Rwanda has spread beyond high-risk groups to the general population of women without known risk factors. For most of these women, a steady male partner is the source of their HIV risk and therefore a vital target for intervention efforts. 相似文献
994.
Thiazide diuretics may preserve bone mass and prevent elderly women's osteopenic fractures, but studies have not distinguished between thiazide preparations or examined former users. We performed a case-control study looking at thiazide use and subsequent hip fracture in postmenopausal female members of the Framingham Study cohort. Cases who had experienced a first hip fracture (n = 176) were compared with age-matched controls (n = 672). Results showed a modest protective effect of any recent thiazide use (not significant). However, recent pure thiazide users experienced significant protection against fracture (adjusted odds ratio, 0.31; 95% confidence interval, 0.11 to 0.88), whereas recent users of combination drugs containing thiazides experienced no protection (adjusted odds ratio, 1.16; 95% confidence interval, 0.44 to 3.05). Combination drugs generally contained only 25 mg of hydrochlorothiazide, suggesting that the small amount of thiazide was insufficient to preserve bone mass. Former thiazide users were not protected against fracture. In sum, recent pure thiazide use in women protects against hip fracture. 相似文献
995.
In 1984, in addition to its standard traditional curriculum, Rush Medical College (Chicago, Ill) developed a Socratic problem-based method of teaching basic science material called the alternative curriculum. As part of an evaluation of this new curriculum, students in the two curricula were compared using three traditional measurements: (1) test scores from the National Board of Medical Examiners, Part I; (2) test scores from the National Board of Medical Examiners, Part II; and (3) performance on an oral examination. Alternative curriculum students did not differ significantly from their traditional curriculum classmates on National Board of Medical Examiners, Part I and Part II total scores, although their subset scores on Part I did tend to be lower, reaching significance in one subset area. Differences in performance favoring the traditional curriculum were primarily seen in the early years of the program. Alternative curriculum students in the class matriculated in 1987 scored significantly higher in three of five categories on the oral examination. 相似文献
996.
Unwanted variations in the rules of practice 总被引:1,自引:0,他引:1
J E Wennberg 《JAMA》1991,265(10):1306-1307
997.
J. E. Hammond R. G. Berger T. S. Carey R. Rutledge T. J. Cleveland J. P. Kichak C. F. Ayscue 《Journal of medical systems》1991,15(3):257-267
Many hospitals today have implemented widely disparate information systems on mainframe and mini-computer hardware. The advent of network technology in hospitals has made it possible to access information in these systems. Unfortunately, the user interfaces to applications on these systems are unique and difficult to learn, which makes them unsuitable for use by clinical services. In this paper we describe the development of a Physician's Workstation which integrates information from multiple existing information systems and discuss how the workstation makes it possible to move from the departmental systems of the present to the computer-based medical record system of the future. 相似文献
998.
999.
Complications associated with central venous catheters inserted in critically ill neonates 总被引:2,自引:0,他引:2
V Hruszkewycz P C Holtrop D G Batton R S Morden P Gibson J D Band 《Infection control and hospital epidemiology》1991,12(9):544-548
OBJECTIVE: To assess the incidence and spectrum of complications associated with central venous catheter (CVC) placement in the critically ill infant. DESIGN: A prospective study of all babies hospitalized in a neonatal intensive care unit (NICU) from January 1989 to December 1989. Potential risk factors associated with infection were evaluated by a case-control comparison. SETTING: Conducted at a university-affiliated, tertiary care community hospital. PATIENTS: Neonates requiring intensive care and a central venous catheter. Controls consisted of noninfected babies. RESULTS: Of 263 critically ill neonates, only 13 (4.9%) required a CVC insertion. Seventeen CVCs were placed in these 13 neonates for a total duration of 600 days (median, 32 days/cannula). Fifteen (88%) of these cannulas had one or more complications during its catheter life including dislodgement or leakage (53%), occlusion or thrombosis (47%), infections (29%), or minor bleeding (12%). Five babies (29%) developed 6 episodes of bloodstream infection including 3 sporadic cases due to Staphylococcus epidermidis and a cluster of fungemia due to Malassezia furfur associated with lipid emulsion therapy. Infants with a CVC-associated infection were a younger gestational age (24 weeks versus 32 weeks, p = .04) and weighed less at birth (580 g versus 1285 g, p = .02). The overall rate of bloodstream infection was one episode per 100 days of catheter use. CONCLUSIONS: CVCs may be lifesaving to a critically ill neonate, but complications occur frequently. Use must be restricted to infants in whom alternate delivery routes of intravenous therapy or support are otherwise unavailable. 相似文献
1000.
D P Taggart D C McMillan T Preston R Richardson A Shenkin H J Burns D J Wheatley 《Nutrition (Burbank, Los Angeles County, Calif.)》1991,7(4):271-274
Total energy expenditure (TEE) was measured by doubly labeled water in 13 preoperative patients undergoing elective coronary artery surgery and compared to resting energy expenditure (REE) measured by indirect calorimetry (IC) calculated from the Harris-Benedict (HB) formula or from formulas based on midarm circumference and arm muscle circumference. Mean REE measured by IC and calculated from the HB, midarm circumference, arm muscle circumference formulas were 62, 75, 62, and 69%, respectively, of TEE measured by doubly labeled water. REE measured by IC correlated significantly with that predicted by the HB (p = 0.006) but not the anthropometric formulas. The relationship between REE derived from anthropometric predictive formulas and REE measured by IC is altered in ischemic heart disease. 相似文献