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41.
Garret Djeu Clarence Shelton Anthony Maganzini 《American journal of orthodontics and dentofacial orthopedics》2005,128(3):292-8; discussion 298
INTRODUCTION: This treatment-outcome assessment objectively compares Invisalign (Align Technology, Santa Clara, Calif) treatment with braces. METHODS: This study, a retrospective cohort analysis, was conducted in New York, NY, in 2004. Records from 2 groups of 48 patients (Invisalign and braces groups) were evaluated by using methods from the American Board of Orthodontics Phase III examination. The discrepancy index was used to analyze pretreatment records to control for initial severity of malocclusion. The objective grading system (OGS) was used to systematically grade posttreatment records. Statistical analyses evaluated treatment outcome, duration, and strengths and weaknesses of Invisalign compared with braces. RESULTS: The Invisalign group lost 13 OGS points more than the braces group on average, and the OGS passing rate for Invisalign was 27% lower than that for braces. Invisalign scores were consistently lower than braces scores for buccolingual inclination, occlusal contacts, occlusal relationships, and overjet. Invisalign's OGS scores were negatively correlated to initial overjet, occlusion, and buccal posterior crossibite. Invisalign patients finished 4 months sooner than those with fixed appliances on average. P < .05 was used to determine statistically significant differences. CONCLUSIONS: According to the OGS, Invisalign did not treat malocclusions as well as braces in this sample. Invisalign was especially deficient in its ability to correct large anteroposterior discrepancies and occlusal contacts. The strengths of Invisalign were its ability to close spaces and correct anterior rotations and marginal ridge heights. This study might help clinicians to determine which patients are best suited for Invisalign treatment. 相似文献
42.
Philip J. Langlais PhD Mark L. Wardlow BS Hitoshi Yamamoto MD 《Pediatric neurology》1991,7(6):440-445
Cerebrospinal fluid (CSF) from 7 patients with infantile spasms (mean age: 6.7 months) was collected before and after treatment with adrenocorticotropic hormone (ACTH). The concentration of neurotransmitter metabolites was analyzed using high-performance liquid chromatography and compared to the metabolite concentration in the CSF from 7 age-matched controls (mean age: 6.1 months). Pretreatment levels of CSF 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid, 3-methoxy-4-hydroxyphenyl glycol (MHPG), and kynurenine were significantly lower in infantile spasm patients compared to controls. Following treatment, marked increases in 5-HIAA and decreases in kynurenine levels were observed in the CSF of the 5 infants whose seizures were eliminated or reduced by ACTH. In the 2 nonresponders 5-HIAA levels decreased. The level of MHPG was reduced slightly in 5 infants, including the 2 nonresponders, and was increased in 2 responders. CSF homovanillic acid levels increased in 4 infantile spasm infants and decreased in 3 following ACTH. These data demonstrate that the presence of seizures in infantile spasms is associated with a significant decrease in serotonergic activity and that elimination of seizures by ACTH is accompanied by increased serotonin turnover. The simultaneous increase of 5-HIAA and decrease of kynurenine, an alternate metabolite of tryptophan, suggests an underlying disturbance of tryptophan metabolism in infantile spasms. The possibility that elimination of seizures by ACTH may be related to decreased production of certain kynurenine metabolites, particularly quinolinic acid, is discussed. 相似文献
43.
Comparison of trichloroethylene and enflurane as adjuncts to nitrous oxide and relaxant anaesthesia 总被引:1,自引:0,他引:1
Forty women who underwent gynaecological surgery were randomly allocated to receive trichloroethylene, enflurane, or enflurane plus fentanyl as adjuncts to nitrous oxide/relaxant anaesthesia with controlled ventilation. No serious cardiac dysrhythmias were seen in any group. Each patient was observed postoperatively for 4 hours by a nurse blind to the technique used, and questioned at 24 hours by a similarly blinded anaesthetist. Recovery after trichloroethylene was not significantly prolonged although postoperative analgesia by visual analogue was better, opiate analgesia was required less frequently and there was less nausea and vomiting than in either of the enflurane groups. We argue for the continued use of trichloroethylene by this technique, because it costs one hundred times less than enflurane and because of the potential morbidity of the postoperative opiate dosage required after enflurane. 相似文献
44.
45.
E.Paul Kirk MB BS J. Santa MD T. Heckler MBA M. Collins MD 《American journal of obstetrics and gynecology》1998,178(6):1222-1228
OBJECTIVE: Our purpose was to assess whether legislative action influenced the role of obstetrician-gynecologists as primary care physicians. STUDY DESIGN: An observational study was performed on the basis of a questionnaire sent to 410 obstetrician-gynecologists and 27 medical directors of managed-care organizations. RESULTS: Of 67% of obstetrician-gynecologists and 96% of medical directors who responded, there was agreement as to the content of primary care, but a minority (38%) of obstetrician-gynecologists identified themselves as primary care providers. A minority of medical directors (35%) felt that obstetrician-gynecologists should serve in that role. Both obstetrician-gynecologists and medical directors felt that legislation had little impact. CONCLUSION: The reticence of obstetrician-gynecologists to assume a major role in primary care appears to be the result of an uneasiness with accepting a more comprehensive role in patient management and gatekeeping. They appear comfortable with the more traditional roles but feel that training and experience has not prepared them well for the management of more complex medical problems. (Am J Obstet Gynecol 1998;178:1222-8.) 相似文献
46.
Localised endosteal bone lysis in relation to the femoral components of cemented total hip arthroplasties 总被引:7,自引:0,他引:7
P P Anthony G A Gie C R Howie R S Ling 《The Journal of bone and joint surgery. British volume》1990,72(6):971-979
Four cases are described of localised endosteal bone lysis in the femur occurring in association with cemented femoral components that were not obviously 'loose' radiologically. In each, the area of lysis was shown at operation to be related directly to a region in which there was a local defect in the cement mantle surrounding the stem. Via the space between the stem and cement, such defects provide a route through which the contents of the joint cavity may reach the endosteal surface of the femur, subsequently leading to localised bone lysis, and later to frank loosening. 相似文献
47.
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49.
Patients'attitudes to rectal drug administration 总被引:2,自引:0,他引:2
One hundred adult patients attending for day case surgery were surveyed by anonymous questionnaire in order to determine their attitudes to rectal drug administration. Fifty four patients did not want an analgesic drug (diclofenac sodium) administered rectally whilst under anaesthesia, all preferring to take it orally if available. Ninety eight patients thought that drugs administered per rectum should always be discussed with them beforehand and a few had very strong feelings about this route of administration. We suggest that prescribers of rectal diclofenac should always discuss it with patients pre-operatively. Whilst many are happy to have suppositories, some young patients are sensitive about this and prefer to take such medication by mouth. 相似文献
50.