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21.

Objective

To investigate the use of time intervals in the treatment of fractured femurs as indicators of the quality of trauma systems.

Methods

Time intervals from injury to admission, admission to surgery and surgery to discharge for patients with isolated femur fractures in four low- and middle-income countries were compared with the corresponding values from one German hospital, an Israeli hospital and the National Trauma Data Bank of the United States of America by means of Student’s t-tests. The correlations between the time intervals recorded in a country and that country’s expenditure on health and gross domestic product (GDP) were also evaluated using Pearson’s product moment correlation coefficient.

Findings

Relative to patients from high-income countries, those from low- and middle-income countries were significantly more likely to be male and to have been treated by open femoral nailing, and their intervals from injury to admission, admission to surgery and surgery to discharge were significantly longer. Strong negative correlations were detected between the interval from injury to admission and government expenditure on health, and between the interval from admission to surgery and the per capita values for total expenditure on health, government expenditure on health and GDP. Strong positive correlations were detected between the interval from surgery to discharge and general government expenditure on health.

Conclusion

The time intervals for the treatment of femur fractures are relatively long in low- and middle-income countries, can easily be measured, and are highly correlated with accessible and quantifiable country data on health and economics.  相似文献   
22.
Spinal cord ependymoma: radical surgical resection and outcome   总被引:22,自引:0,他引:22  
Hanbali F  Fourney DR  Marmor E  Suki D  Rhines LD  Weinberg JS  McCutcheon IE  Suk I  Gokaslan ZL 《Neurosurgery》2002,51(5):1162-72; discussion 1172-4
OBJECTIVE: Several authors have noted increased neurological deficits and worsening dysesthesia in the postoperative period in patients with spinal cord ependymoma. We describe the neurological progression and pain evolution of these patients over the 1-year period after surgery. In addition, our favored method of en bloc tumor resection is illustrated, and the rate of complications, recurrence, and survival in this group of patients is addressed. METHODS: We operated on 26 patients (12 male and 14 female) with low-grade spinal cord ependymomas between 1975 and 2001. The median age at diagnosis was 42 years. Tumors extended into the cervical cord in 13 patients, the thoracic cord in 7 patients, and the conus medullaris in 6 patients. Eleven patients had previous surgery and/or radiation therapy. RESULTS: We achieved a gross total resection in 88% of patients, whereas 8% had a subtotal resection and 4% had a biopsy. Only 1 patient developed a recurrence over a mean follow-up period of 31 months. CONCLUSION: We conclude that radical surgical resection of spinal cord ependymomas can be safely achieved in the majority of patients. A trend toward neurological improvement from a postoperative deficit can be expected between 1 and 3 months after surgery and continues up to 1 year. Postoperative dysesthesias begin to improve within 1 month of surgery and are significantly better by 1 year after surgery. The best predictor of outcome is the preoperative neurological status.  相似文献   
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24.
Vertebrate vision starts with photoisomerization of the 11-cis-retinal chromophore to all-trans-retinal. Biosynthesis of 11-cis-retinal is required to maintain vision. A key enzyme catalyzing the oxidation of 11-cis-retinol is 11-cis-retinol dehydrogenase (11-cis-RDH), which is encoded by the RDH5 gene. 11-cis-RDH is expressed in the RPE and not in the neural retina. The consequences of a lack of 11-cis-RDH were studied in a family with fundus albipunctatus. We identified the causative novel RDH5 mutation, Arg157Trp, that replaces an amino acid residue conserved among short-chain alcohol dehydrogenases. Three-dimensional structure modeling and in vitro experiments suggested that this mutation destabilizes proper folding and inactivates the enzyme. Studies using RPE membranes indicated the existence of an alternative oxidizing system for the production of 11-cis-retinal. In vivo visual consequences of this null mutation showed complex kinetics of dark adaptation. Rod and cone resensitization was extremely delayed following full bleaches; unexpectedly, the rate of cone recovery was slower than rods. Cones showed a biphasic recovery with an initial rapid component and an elevated final threshold. Other unanticipated results included normal rod recovery following 0.5% bleach and abnormal recovery following bleaches in the 2-12% range. These intermediate bleaches showed rapid partial recovery of rods with transitory plateaux. Pathways in addition to 11-cis-RDH likely provide 11-cis-retinal for rods and cones and can maintain normal kinetics of visual recovery but only under certain constraints and less efficiently for cone than rod function.  相似文献   
25.
G. H. A. Hansen (1841-1912) is widely known as the discoverer of the infectious cause of leprosy. It is less well known that his career was threatened by an episode involving experimentation on the eye. As a staff physician at the leprosy hospitals of Bergen, Norway, early in his career, Hansen learned about ocular involvement in leprosy and co-authored Leprous Diseases and the Eye. In 1873 he observed bacilli in leprous nodules, but proof of an infectious origin was difficult to obtain because the agent could not be cultured and no one had demonstrated direct transmission. Hansen tried several unsuccessful experiments, and in 1879 he passed a cataract knife that had incised an active leprous nodule into a woman's conjunctiva. No nodule developed, but the woman complained of pain and said she was never asked for permission. Hansen was brought to trial where eminent physicians testified on his behalf-but Hansen himself readily admitted that no permission had been sought for fear the woman would say no. He was convicted, and relieved of his post as staff physician, but he was allowed to retain an appointment as Chief Medical Officer of Health for Leprosy, in which capacity he worked for the rest of his life.  相似文献   
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27.
Recognition of small stimulus screen masks using the multifocal ERG   总被引:1,自引:0,他引:1  
To evaluate the ability of the multifocal ERG (mfERG) to detect small defects in the stimulus array was the objective of this paper. Seven normal subjects had mfERGs recorded with a VERIS system. Stimulus arrays composed of 61, 103 or 241 hexagons were covered in part by small masks of different light transmittance properties. Only masks that covered at least one-half of a single 103 hexagon stimulus cell caused a significant reduction in signal. Different-shaped masks of about 5° diameter were detectable using a 61-hexagon array only when they fully covered a stimulus cell. Detection was better, but marginal for some of the masks, with the 103 hexagon array. The 241 hexagon array showed sharp defects for all masks. Masking the stimulus screen is not equivalent to having a pathologic scotoma, but it demonstrates the greatest possible spatial sensitivity of the mfERG system. Thus, the mfERG appears to be able to detect small retinal lesions if they reduce local retinal function by at least 50% and correspond to at least half the area of one stimulus hexagon. Scotomas 5° or smaller would be best detected using a fine (241 hexagon) stimulus array. With coarser stimulus arrays (e.g. 103 or 61 hexagons), the effect of a small scotoma depends on its location relative to the stimulus cells. These issues should be considered when selecting mfERG recording conditions.  相似文献   
28.
BACKGROUND: Douching may interfere with determination of microbicide safety and effectiveness. This practice has not been adequately studied among women at risk of HIV infection. GOAL: This study assessed douching practices among women at risk of HIV infection in the United States. STUDY DESIGN: Data were collected on douching practices, sexually transmitted diseases, birth control, use of spermicidal products, and sexual risk behaviors among HIV antibody-negative women. RESULTS: Of 623 women, 70.2% had recently douched. Most women had been told that douching was not healthy. No associations were found between recent douching and measures of risk behaviors, except number of male partners. Recent douching was associated with being aged 26 to 30 years, compared with being 18 to 25 years of age (odds ratio [OR] = 2.2), black (OR = 3.0), or sterilized (OR = 2.0); having 5 or more male partners (OR = 4.4); and being told that douching is unhealthy (OR = 0.4). CONCLUSIONS: Recent douching was very common. The high prevalence of douching has implications for the design of microbicide trials and prevention interventions.  相似文献   
29.
BACKGROUND: When operating hair removal lasers on the face or in the periorbital region, even with an ocular shield in place, patients often report seeing "flashing lights" each time the laser is fired. This phenomenon suggests stimulation of retinal photoreceptors and raises laser safety issues. OBJECTIVE: To perform retinal electrophysiologic studies to evaluate the safety of hair removal lasers in the periorbital region. METHODS: Five patients with severe trichiasis secondary to trachoma were studied. The 810 nm Dioderm laser (Cynosure, Inc., Chelmsford, MA) was used to treat the eyelash follicles on the lower eyelid of each patient. Cox III metal eye shields (Oculo-Plastik, Inc., Montreal, Canada) were placed behind the eyelids of both eyes during the laser procedure. Prior to irradiation, a comprehensive ophthalmic evaluation including pupillary and slit-lamp examination, funduscopy, and full-field electroretinograms (ERGs) was performed. A comprehensive ophthalmic evaluation including ERG testing was repeated 30 minutes and 3-6 months after completion of treatment. An independent blinded assessor evaluated the ERG studies. Subjective reports of laser light sensation, pain, and discomfort during and after the laser procedure were also assessed. RESULTS: There was no detectable change in slit-lamp, pupillary, or funduscopic evaluations after periorbital laser irradiation. Similarly the pre- and posttreatment ERGs were unchanged. Three patients reported seeing flashing lights during the procedure. CONCLUSION: We found no ERG evidence of retinal damage after laser hair removal in the periorbital region, with Cox III-type ocular shields over the eyes, even when patients subjectively reported "flashing lights" during laser irradiation.  相似文献   
30.
The biological correlates of an effective immune response that could contain or prevent HIV infection remain elusive despite substantial scientific accomplishments in understanding the interactions among the virus, the individual and the community. The observation that some individuals appear to possess resistance to HIV infection or its consequences has generated a host of epidemiologic investigations to identify biological or behavioral characteristics of these individuals. These data might hold the keys to developing appropriate strategies for mimicking the effective responses of those who appear immune. In this paper we review genetic mechanisms including the role of chemokines and their receptors, cytokines, host genetic immune response to HIV infection, local immune response correlating with behavioral variables, co-infection and immune based mechanisms that have been elucidated so far. We offer suggestions for how to use these observations as platforms for future research to further understand natural resistance to HIV infection through cohort studies, population genotype sampling, mathematical modeling of virus–host interactions and behavioral analyses. Marmor, Hertzmark and Thomas are with the Department of Environmental Medicine, New York University School of Medicine, 650 First Avenue, Room 560, New York, NY 10016, USA; Marmor is with the Department of Medicine, New York University School of Medicine, New York, NY, USA; Marmor, Hertzmark, Thomas, and Halkitis are with the The Center for AIDS Research, New York University School of Medicine, New York, NY, USA. Halkitis is with the Department of Applied Psychology, New York University Steinhardt School of Education, New York, NY, USA; Vogler is with the Division of International Medicine and Infectious Diseases, Weill Cornell College of Medicine, New York, NY, USA.  相似文献   
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