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51.
For the past 45 years, there has been a great deal of debate regarding the health issues surrounding the fluoridation of public water supplies. In order to assess the association between fluoridation and hip fracture, we identified 129 counties across the United States considered to be exposed to public water fluoridation and 194 counties without exposure. Data from the Health Care Financing Administration and the Department of Veterans Affairs were used to calculate the incidence of hip fracture among white persons, aged 65 years or older, in fluoridated and nonfluoridated counties. There was a small statistically significant positive association between fracture rates and fluoridation. The relative risk (95% confidence interval) of fracture in fluoridated counties compared to nonfluoridated counties was 1.08 (1.06 to 1.10) for women and 1.17 (1.13 to 1.22) for men. As comparisons were made at the grouped level, it may be inappropriate at this time to draw inferences at the individual level. The relationship observed at the county level needs to be duplicated at the individual level with more precise measures of fluoride exposure.  相似文献   
52.
One of the most exciting developments in pediatric dermatology has been the use of the flashlamp-pumped, 585-nm, pulsed dye laser for treatment of vascular birthmarks. In many cases the results are miraculous. The increase in self-esteem and happiness of many children and adolescents has been overwhelming; for some, depression has been lifted, stuttering has ceased, social involvement has increased, and antidepressants have been discontinued. There are many success stories to tell.
Despite the remarkable effects of the pulsed dye laser and the medical and psychosocial indications for its use, the issue of pain control remains significant. We have no perfect outpatient pediatric anesthetic. Most methods carry either some risk or, if not hazardous, often are not very effective for controlling pain. Needless to say, a diversity of opinions exist on how to manage discomfort from this treatment modality. Therefore, we thought it would be useful to share the experiences and opinions of several dermatologists who have extensive experience with the pulsed dye laser.  相似文献   
53.
A comprehensive anatomic and radiographic analysis of the peribursal fat plane in 12 cadavers confirmed that the fat plane seen on radiographs represents extrasynovial fat lining the subacromial bursa and documented the anatomic relations of the bursa. A three-part retrospective clinical evaluation of rotator cuff tears, calcific tendinitis, and rheumatoid arthritis was performed. Two osteoradiologists blindly graded the appearance of the peribursal fat plane with the shoulder in external versus internal rotation in 21 patients with arthrographically intact rotator cuffs and 21 patients with disrupted rotator cuffs. The peribursal fat plane was seen better with disrupted rotator cuffs. The peribursal fat plane was seen better with the shoulder in internal rotation and was seen in 60% of control subjects but only 21% of patients with rotator cuff tears. Partial or complete obliteration of this fat plane is a sensitive (79%) but less specific (60%) indicator of rotator cuff tears. Obliteration of the peribursal fat plane by inflammatory processes in adjacent tissues, including calcific tendinitis and rheumatoid arthritis, occurred with a high frequency.  相似文献   
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Patients with total colonic ulcerative colitis or familial polyposis traditionally require a proctocolectomy. In an effort to preserve the normal pathway for defecation and avoid the nuisance of an abdominal stoma, a continence-preserving procedure involving a pelvic reservoir has been performed at the University of Minnesota Hospitals on 120 patients. The majority were operated on for colonic ulcerative colitis. There were no deaths. The mean hospital stay after restorative proctocolectomy was 10 days and after ileostomy takedown the mean stay was 7 days. Functional results were assessed in 52 patients. Daytime bowel movements averaged 6.4 and night-time movements 1.4. Major daytime incontinence occurred in 6% of the patients, 21% had moderate soiling at night and 70% wore a perineal pad in the evening. Ninety-two percent of the patients expressed satisfaction with the procedure. The most serious complication was pelvic sepsis. It occurred in nine patients, six of whom required subsequent surgery. The Parks S pouch provides a means of maintaining anal continence. This series and others have shown that young, healthy, well-motivated persons will benefit most from a restorative proctocolectomy.  相似文献   
56.
Celiprolol is reported to be a new cardioselective beta blocker with novel ancillary properties including vasodilator effects. The purpose of this study was to investigate whether celiprolol possesses a direct vasodilatory effect on human vasculature in vivo and in vitro. We studied the in vivo effects of intra-arterial celiprolol (1-100 micrograms/min i.a.) on forearm blood flow (FBF). Forearm blood was measured by venous occlusion plethysmography. Possible vasorelaxant actions of celiprolol on human vascular smooth muscle were studied using segments of isolated human saphenous vein in vitro. The effect of celiprolol was investigated on resting tone or noradrenaline induced tone. Possible alpha 2-adrenoceptor antagonist effects of celiprolol were assessed using celiprolol as an antagonist of BHT933 induced constriction. Celiprolol was without significant effect on FBF and failed to relax isolated saphenous vein segments preconstricted with noradrenaline. The weak alpha 2-adrenoceptor antagonist action of celiprolol was demonstrable in human saphenous vein. This study does not provide evidence for a direct vasodilatory effect of celiprolol on human vasculature.  相似文献   
57.
Acute retinal necrosis   总被引:5,自引:0,他引:5  
Five patients with the acute stages of acute retinal necrosis underwent vitrectomy, with acyclovir in the infusion fluid, and the placement of a 360 degrees scleral buckle after intravenous therapy with acyclovir. Anatomic reattachment was achieved in all patients, and improvement over preoperative visual acuity was obtained in four. Recommendations for the treatment of acute retinal necrosis include a high index of suspicion in healthy patients with retinitis, early diagnosis, early intravenous therapy with acyclovir, early pars plana vitrectomy with the use of intravitreal acyclovir in the infusion fluid, and a 360 degrees scleral buckling procedure.  相似文献   
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59.
What Are American Children Eating? Implications for Public Policy   总被引:2,自引:0,他引:2  
As the health and demographic profile of the U.S. population changes, the food consumption patterns of American children have also changed. This review is organized around a series of policy issues looking at these new food consumption patterns, their relationship to the Dietary Guidelines, and their impact on children's health.  相似文献   
60.
The most advantageous combination of immunosuppressive agents for cardiac transplant recipients has not yet been established. Between November 2001 and June 2003, 343 de novo cardiac transplant recipients were randomized to receive steroids and either tacrolimus (TAC) + sirolimus (SRL), TAC + mycophenolate mofetil (MMF) or cyclosporine (CYA) + MMF. Antilymphocyte induction therapy was allowed for up to 5 days. The primary endpoint of >/=3A rejection or hemodynamic compromise rejection requiring treatment showed no significant difference at 6 months (TAC/MMF 22.4%, TAC/SRL 24.3%, CYA/MMF 31.6%, p = 0.271) and 1 year (p = 0.056), but it was significantly lower in the TAC/MMF group when compared only to the CYA/MMF group at 1 year (23.4% vs. 36.8%; p = 0.029). Differences in the incidence of any treated rejection were significant (TAC/SRL = 35%, TAC/MMF = 42%, CYA/MMF = 59%; p < 0.001), as were median levels of serum creatinine (TAC/SRL = 1.5 mg/dL, TAC/MMF = 1.3 mg/dL, CYA/MMF = 1.5 mg/dL; p = 0.032) and triglycerides (TAC/SRL = 162 mg/dL, TAC/MMF = 126 mg/dL, CYA/MMF = 154 mg/dL; p = 0.028). The TAC/SRL group encountered fewer viral infections but more fungal infections and impaired wound healing. These secondary endpoints suggest that the TAC/MMF combination appears to offer more advantages than TAC/SRL or CYA/MMF in cardiac transplant patients, including fewer >/=3A rejections or hemodynamic compromise rejections and an improved side-effect profile.  相似文献   
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