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101.
Folic acid has been shown to reduce the risk of pregnancies affected by neural tube defects (NTDs) by as much as 70%. Cereal grains sold in the U.S. have been fortified with folic acid since 1998. The Arkansas Reproductive Health Monitoring System and the Arkansas Folic Acid Coalition have encouraged use of folic acid and monitored the impact of increased consumption of folic acid among Arkansans. NTDs in Arkansas have declined 40% since intervention programs were implemented. The greatest decline has been observed among white and Hispanic women. Efforts to encourage folic acid consumption should continue to target Arkansas women. NTDs include anencephaly and spina bifida. These birth defects result from incomplete closure of the fetal neural tube during the first month of pregnancy. Infants with anencephaly are born without all or most of their brain and die within a few days of life. Infants with spina bifida have varying degrees of impairment ranging from little noticeable disability to severe, lifelong disability. Folic acid, when taken in supplement form has been shown to reduce the risk of a pregnancy affected by a neural tube defect by as much as 70%. As a result of this finding, the U.S. Federal Drug Administration mandated that cereal grains sold in this country be fortified with at least 140 mcg of folic acid per 100 grams of grain by January 1, 1998. Prior to mandatory fortification, the March of Dimes and the U.S. Public Health Service released statements encouraging all women of reproductive age who are capable of becoming pregnant to take 400 mcg 'of synthetic folic acid daily. The Arkansas Reproductive Health Monitoring System (ARHMS) has monitored rates of NTDs in Arkansas since 1980. ARHMS is the lead agency of the Arkansas Folic Acid Coalition whose mission is to encourage folic acid use among all Arkansas women of reproductive age. In this report, we summarize efforts by ARHMS and the Arkansas Folic Acid Coalition to increase the awareness and use of folic acid in Arkansas, show how the rates of NTDs in the state have declined over the past 10 years, and estimate the direct health care and productivity cost savings to Arkansans over that time.  相似文献   
102.
OBJECTIVE: To evaluate the safety and efficacy of 5% imiquimod cream for cutaneous dysplasia in high-risk renal transplant recipients. DESIGN: A randomized, blinded, placebo-controlled study comparing treated with control skin. SETTING: A specialist organ transplant dermatology clinic. PATIENTS: Twenty-one high-risk patients with skin cancer with comparable areas of clinically atypical skin on dorsal hands or forearms. INTERVENTIONS: Imiquimod or placebo (randomly assigned) applied 3 times a week for 16 weeks to 1 dorsal hand or forearm, with 8 months of follow-up. At week 16, biopsy samples were collected from pre-assigned sites in the treatment and control areas and were examined for dysplasia. MAIN OUTCOME MEASURES: The proportion of patients showing reduced numbers of viral and keratotic lesions and reduced histological severity of dysplasia in the treatment vs control areas at week 16, serum creatinine levels, and tumors developing in the study sites. RESULTS: Fourteen patients receiving imiquimod and 6 receiving placebo completed the study. Seven patients using imiquimod (1 taking placebo) had reduced skin atypia, 7 using imiquimod (none taking placebo) had reduced viral warts, and 5 using imiquimod (1 taking placebo) showed less dysplasia histologically. In 1 year, fewer squamous skin tumors arose in imiquimod-treated skin than in control areas. Renal function was not adversely affected. CONCLUSIONS: Topical 5% imiquimod cream seems to be safe on skin areas up to 60 cm2 in renal transplant recipients. It may be effective in reducing cutaneous dysplasia and the frequency of squamous tumors developing in high-risk patients. Larger studies are required to confirm these results.  相似文献   
103.
PURPOSE: To evaluate the reduction in the anterior capsule opening after phacoemulsification, continuous curvilinear capsulorhexis, and implantation of 1 of 2 acrylic intraocular lenses (IOLs). SETTING: Department of Ophthalmology, Vejle Hospital, Vejle, Denmark. METHODS: Eighty-four patients (84 eyes) were included in a prospective randomized study. All had phacoemulsification followed by implantation of an IOL with a modified anterior edge (38 eyes) or a sharp anterior edge (46 eyes). One day (baseline) and 3 months postoperatively, the area of the anterior capsule opening was measured using retroillumination photographs. RESULTS: There was a significant reduction in the area of the anterior capsule opening from 1 day to 3 months postoperatively in both groups (P<.001). There was no significant difference in the reduction in the anterior capsule opening between the modified-edge IOL and the sharp-edged IOL (P = .313). The shrinkage was independent of the area of the anterior capsule opening at baseline. CONCLUSIONS: There was a reduction in the area of the anterior capsule opening in all patients. The design of the anterior edge of the 2 IOLs did not influence the degree of anterior capsule opening shrinkage. The shrinkage was independent of the size of the area 1 day postoperatively.  相似文献   
104.
BACKGROUND: Because gonococcal and chlamydial infections are often asymptomatic, disease control requires population-based screening. This report describes the feasibility of home-based testing for sexually transmitted diseases (STDs) and of specimen transport via the US mail. GOAL: This project sought to establish the efficacy and acceptability to the public of screening by means of urine kits made available in public places and mailed in for STD testing. STUDY DESIGN: Self-selected community participants obtained STD test kits from local businesses, collected urine specimens at home, and mailed kits to the health department for nucleic acid amplification testing. RESULTS: Participants picked up 209 test kits and returned 80 (38%): 3 (3.8%) of 76 were positive for gonorrhea and 1 (1.3%) of 76 was positive for chlamydia. The majority (95%) of participants were white gay men. The cost of specimen collection and transport was similar to that of other population-based screening programs. CONCLUSION: Using the mail for home-based testing for gonorrhea and chlamydia was feasible and may be a useful addition to STD control efforts.  相似文献   
105.
BACKGROUND: Previous school-based studies in cities with a high prevalence of chlamydia found a substantial prevalence of chlamydial infection among students. GOAL: The goal was to determine the feasibility and acceptability of chlamydia and gonorrhea screening in San Francisco high schools. STUDY DESIGN: Sexually transmitted disease (STD) education and screening were conducted at four high schools. Students provided basic demographic information and urine specimens for chlamydia and gonorrhea ligase chain reaction testing. RESULTS: Among 283 asymptomatic females screened, 3.9% had chlamydia and 0.7% had gonorrhea. The prevalence of chlamydia was 1.5% among females <16 years of age and 4.6% among females >or=16 years of age. Only 0.8% of asymptomatic males (3/381) had chlamydia, and none had gonorrhea. CONCLUSION: STD screening was both feasible and acceptable in San Francisco high schools. STD screening in high schools should be prioritized as follows: (1) chlamydia screening over gonorrhea screening, (2) female screening over male screening, and (3) screening of older students (juniors and seniors) over screening of younger students.  相似文献   
106.
BACKGROUND: To assess the prevalence and increase awareness of Neisseria gonorrhoeae and Chlamydia trachomatis infections among men who have sex with men, a screening program was conducted at three inner-city homosexual entertainment venues and one community function. STUDY DESIGN: Each venue was accessed twice over a 3-month period between March and June 2000. First-catch urine specimens were collected for analysis by polymerase chain reaction (PCR), and throat swabs were collected for culture and PCR. RESULTS: A total of 202 men were tested during the 7 screening nights, including 16 who were tested more than once. From the 186 men tested for the first time, 184 urine specimens were collected, of which 8 (4.3%; 95% CI, 1.9-7.8%) were PCR-positive for C trachomatis and 1 (0.5%; 95% CI, 0-2.1%) was PCR-positive for N gonorrhoeae. Of the 161 throat swabs collected, none were positive for C trachomatis or N gonorrhoeae. CONCLUSIONS: C trachomatis is a potentially significant pathogen in this population of urban homosexual men. Screening programs such as these are valuable as health-promotion exercises.  相似文献   
107.

Background

Bodybuilding is a demanding sport, which requires high-volume, high-resistance weight training and augmented nutritional intake, toward an increase of overall body muscle mass accompanied by an overall decrease of body fat percentage and mass. Among bodybuilders, the use of various legal and illegal supplements is common. These supplements may be naturally occurring or man-made.

Case Report

We discuss the case of a 30-year-old male bodybuilder presenting with coma due to severe hypoglycemia from unknown cause, necessitating iterative glucose infusions, which was subsequently found to be related to cryptic insulin injections.

Why Should an Emergency Physician Be Aware of This?

In strength athletes, especially amateurs, the recourse to performance-enhancement drugs (e.g., insulin) is frequent. Beyond the specificity of care required for surreptitious insulin intoxication, emergency physicians should be alert to the possibility that exogenous insulin has been injected for use as an ergogenic aid by bodybuilders and others seeking to increase their body muscle mass when they encounter a patient with a decreased level of consciousness and treatment-refractory hypoglycemia. Moreover, in case of suspicion of such intoxication, the use of other illegal supplements should be screened, due to potentially associated risks of complication.  相似文献   
108.
Contactins are a group of cell adhesion molecules that are mainly expressed in the brain and play pivotal roles in the organization of axonal domains, axonal guidance, neuritogenesis, neuronal development, synapse formation and plasticity, axo-glia interactions and neural regeneration. Contactins comprise a family of six members. Their absence leads to malformed axons and impaired nerve conduction. Contactin mediated protein complex formation is critical for the organization of the axon in early central nervous system development. Mutations and differential expression of contactins have been identified in neuro-developmental or neurological disorders. Taken together, contactins are extensively studied in the context of nervous system development. This review summarizes the physiological roles of all six members of the Contactin family in neurodevelopment as well as their involvement in neurological/neurodevelopmental disorders.  相似文献   
109.
This study attempted to identify factors associated with mortality among human immunodeficiency virus (HIV)-infected adults starting a protease inhibitor (PI)-containing therapy. Among 1155 patients consecutively enrolled in the APROCO study between May 1997 and June 1998, clinical characteristics were as follows: median age, 36 years; median baseline CD4 cell count, 288 cells/mm(3); and median baseline plasma HIV RNA load, 4.4 log(10) copies/mL. After a median follow-up of 27 months, 48 deaths had occurred, of which 44% were related to acquired immune deficiency syndrome. The mortality rate was 2.9% at 12 months. When both data at baseline and data at 4 months after the start of PI therapy were considered, factors independently associated with mortality were (Cox model) low baseline plasma creatinine level, low school education level, low CD4 cell count at 4 months, low hemoglobin level, and elevated hepatic transaminase levels. Thus, social context plus clinical and biologic data, including the 4-month response to treatment, must be considered in treatment of HIV-infected patients.  相似文献   
110.
OBJECTIVE: To evaluate whether hospital volume and surgeon volume of total hip replacements (THRs) are associated with patient-reported functional status and satisfaction with surgery 3 years postoperatively. METHODS: We performed a population-based cohort study of a stratified random sample of Medicare beneficiaries who underwent elective primary or revision THR in Ohio, Pennsylvania, or Colorado in 1995. The primary outcomes were the self-reported Harris hip score and a validated scale measuring satisfaction with the results of surgery. Both outcomes were assessed 3 years postoperatively. Hospital volume was defined as the aggregate number of elective primary and revision THRs performed on Medicare beneficiaries in the hospital in 1995. High-volume hospitals were defined as those in which >100 such procedures are performed annually, and low-volume centers were defined as those in which 12 procedures per year. CONCLUSION: Hospital volume and surgeon volume have little effect on 3-year functional outcome following THR, after adjusting for patient sociodemographic and select clinical characteristics. However, satisfaction with primary THR is greater among patients who underwent surgery in high-volume centers, and satisfaction with revisions is greater among patients whose operations were performed by higher-volume surgeons. Referring clinicians should incorporate these findings into their discussion of referral choices with patients considering THR. Conclusions regarding the effect of volume on longevity of the implants must await longer-term followup studies. Finally, further research is warranted to better understand the association between hospital and surgeon procedure volume and patient satisfaction with surgery.  相似文献   
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