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911.
912.
Fernando E. Boada Gary X. Shen Sam Y. Chang Keith R. Thulborn 《Magnetic resonance in medicine》1997,38(6):1022-1028
A scheme for the reduction of T2 signal attenuation effects in three-dimensional twisted projection imaging is presented. By purposely reducing the sample density at the high spatial frequencies, a considerable reduction in readout time is achieved. The reduction in readout time leads to decreased T2 signal attenuation which translates into improved signal-to-noise ratio (SNR). The SNR improvement is achieved without decreasing the image's resolution since the point spread function depends on the sample weighting as well as the T2 attenuation. The results indicate that SNR improvements of up to 40% can be achieved using the proposed scheme. 相似文献
913.
Abstract: Osteochondromas are among the most common cartilaginous neoplasms, but are rarely seen on the fingers and toes. We report a 10-year-old girl who had a dystrophic fingernail since Infancy that was identified as a subungual Osteochondroma radiologically and histopathologically. The clinical, radiographic, and histopathologic features, as well as the pertinent differential diagnoses and treatment options are discussed. 相似文献
914.
Comorbidity of mental disorders with alcohol and other drug abuse. Results from the Epidemiologic Catchment Area (ECA) Study 总被引:35,自引:1,他引:34
The prevalence of comorbid alcohol, other drug, and mental disorders in the US total community and institutional population was determined from 20,291 persons interviewed in the National Institute of Mental Health Epidemiologic Catchment Area Program. Estimated US population lifetime prevalence rates were 22.5% for any non-substance abuse mental disorder, 13.5% for alcohol dependence-abuse, and 6.1% for other drug dependence-abuse. Among those with a mental disorder, the odds ratio of having some addictive disorder was 2.7, with a lifetime prevalence of about 29% (including an overlapping 22% with an alcohol and 15% with another drug disorder). For those with either an alcohol or other drug disorder, the odds of having the other addictive disorder were seven times greater than in the rest of the population. Among those with an alcohol disorder, 37% had a comorbid mental disorder. The highest mental-addictive disorder comorbidity rate was found for those with drug (other than alcohol) disorders, among whom more than half (53%) were found to have a mental disorder with an odds ratio of 4.5. Individuals treated in specialty mental health and addictive disorder clinical settings have significantly higher odds of having comorbid disorders. Among the institutional settings, comorbidity of addictive and severe mental disorders was highest in the prison population, most notably with antisocial personality, schizophrenia, and bipolar disorders. 相似文献
915.
916.
917.
Keith L. Kaufman PhD Daniel R. Hilliker MA Patty Lathrop MA Eric L. Daleiden MA 《Sexual abuse : a journal of research and treatment》1993,6(3):213-229
Recent evidence suggests that child sexual offenders' self-report can provide a reliable source of information regarding offenders' use of threats and violence. However, the majority of studies in this area have specifically focused on coercion occurring within sexually abusive acts. The current investigation examined the accuracy of offenders' self-report regarding their use of threats and violence with child and adolescent victims during two time periods: (1) while attempting to secure victims' cooperation in sexual activities; and (2) while seeking to maintain victims' silence regarding the abuse. The responses of 16 offenders in an incarcerated treatment setting and 16 in an outpatient treatment program were compared with treatment staff's responses on an anonymous questionnaire. Findings generally indicated a high level of concordance between offender and staff reports. However, both groups of offenders significantly under-reported their use of threats and violence for both time periods. While some of the under-reported items reflected overt forms of violence (e.g., forced participation), the majority represented subtle, manipulative, and/or implied threats. Implications for future studies and clinical applications are discussed. 相似文献
918.
Michael Patrick Clarke Keith William Mitchell Sharon McDonnell 《Documenta ophthalmologica. Advances in ophthalmology》1996,92(4):325-339
The flash and pattern electroretinogram were investigated in a group of families with rare forms of inherited macular dystrophy,
which included Sorsby's fundus dystrophy, X-linked retinoschisis and macular dystrophy of uncertain classification and variable
expression. Flash electroretinograms, under both photopic and scotopic conditions, were attenuated in both Sorsby's fundus
dystrophy and X-linked retinoschisis—with some effect on implicit time being noted in the latter condition—but in the unknown
group the effect was less demonstrable, only 50% having attenuated flash electroretinograms. Pattern electroretinograms were
reduced in all three conditions and in almost all cases. The study demonstrates that some so-called macular dystrophies also
have widespread abnormalities affecting the peripheral retina. These findings may contribute to a better understanding of
the underlying pathophysiologic mechanisms in these rare forms of retinal dysfunction. 相似文献
919.
Michinaga Takahashi M.D. Bao-Lien Nguyen Tu M.D. Edoardo Leombruni M.D. Keith A. Kelly M.D. 《Journal of gastrointestinal surgery》1997,1(6):545-553
The aim of this study was to determine whether the use of an ileal Roux limb, rather than a jejunal Roux limb, would prevent
the Roux stasis syndrome that can occur after Roux gastrectomy. An ileal Roux limb was constructed in eight dogs and anastomosed
to the gastric remnant after distal hemigastrectomy. Flow of chyme through the jejunum was preserved via an ileojejunostomy
and a jejunoileostomy. Six dogs with distal gastrectomy and a conventional Roux gastrojejunostomy served as a control group.
Chronic enteric recording electrodes and intraluminal, open-tipped pressure catheters were implanted in all dogs. After recovery,
the electrical activity and motility of the Roux limbs and the rates of gastric emptying of liquids and solids were measured.
Dogs with a Roux gastroileostomy had a slower frequency of pacesetter potentials in the Roux limb, a greater Roux motility
index, and a faster rate of gastric emptying of liquids and solids than did dogs with a Roux gastrojejunostomy. Stomal ulcers,
however, developed in seven of the eight ileal Roux limbs but in none of the jejunal Roux limbs. It was concluded that Roux
gastroileostomy does ameliorate the Roux stasis syndrome, but there is a greater risk of stomal ulceration in the limb.
Supported by the Mayo Foundation, Tohoku University, and the Nigro Grant.
Presented at the Annual Meeting of the American Gastroenterological Association, May 22, 1996, San Francisco, Calif. 相似文献
920.
Lamotrigine High-Dose Tolerability and Safety in Patients with Epilepsy: A Double-Blind, Placebo-Controlled, Eleven-Week Study 总被引:3,自引:2,他引:1
Fumisuke Matsuo Patricia Gay Jack Madsen Keith G. Tolman Douglas E. Rollins Marcus E. Risner Allen A. Lai† 《Epilepsia》1996,37(9):857-862
Summary: Purpose: This study was undertaken to evaluate the dose tolerability and safety of a chronic ascending twice-daily (b.i.d.) dosage regimen of 700 mg/day larnotrigine (LTG) and to include determination of the LTG pharmacokinetic profile at doses 500 mg/day in patients receiving concomitant enzyme-inducing antiepileptic drugs (AEDs). Methods: Twelve adult male epileptic patients treated with enzyme-inducing AEDs received 700 mg/day (b.i.d.) oral LTG (n = 8) or placebo (controls, n = 4). For 3 weeks, as outpatients they had their LTG dosage increased from 100 to 400 mg/day. Then, in a clinical research study unit, patients received regimens of 500, 600, and 700 mg/day for 1 week each. Controls received matching placebo in the same sequence. At study end, dosages were tapered in 2 weeks. Follow-up evaluations were made 7 days later. Results: Five LTG patients tolerated 700 mg/day for 1 week. LTG was reduced to 600 mg/day in a patient with mild diplopia and to 500 mg/day in a patient with mild oscillopsia and diplopia. One patient discontinued 300-mg/day therapy with a moderately intense diffuse papular skin rash, attributed to LTG. Headache, drowsiness, faintness, and diplopia, the common adverse events (AEs), were mild to moderate in intensity and occurred in 50–75% of patients in both groups (except for diplopia, occurring only with LTG). Concomitant AED plasma concentrations were not markedly changed by LTG. LTG pharmacokinetics were linear over the range of 500–700 mg/day. Conclusions: LTG doses 700 mg/day can be tolerated in patients receiving concomitant enzyme-inducing AEDs. 相似文献