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991.
We report on the long-term followup of a mixed dissociative (conversion) disorder after circumcision in childhood. 相似文献
992.
Quantitative perfusion measurements using pulsed arterial spin labeling: effects of large region-of-interest analysis 总被引:5,自引:0,他引:5
PURPOSE: To study arterial spin labeling (ASL) MRI techniques and to investigate various problematic issues that still hinder the accurate and robust quantitative analysis of ASL data. MATERIALS AND METHODS: A pulsed-ASL (PASL) sequence was implemented on a 3-T imaging system and a protocol was developed for the measurement of perfusion based on fitting to a standard kinetic model. Both numerical simulations and multi-inversion time MRI data were analyzed. The effect of fitting a kinetic curve to a large region of interest (ROI) with a distribution of arterial transit times was compared to a pixel-by-pixel (PBP) method. RESULTS: It was found that a significant underestimation of perfusion of approximately 17+/-6% (P<0.001) occurs in gray matter, when comparing an ROI with a PBP analysis over a group of 12 healthy subjects. CONCLUSION: Analysis of ASL data based on a large ROI may suffer from inaccuracies arising from a distribution of transit times, implying that averaging of ASL kinetic data over such regions should therefore be avoided. When possible, a PBP fit should be performed. 相似文献
993.
994.
Nonrandom ascertainment is commonly used in genetic studies of rare diseases, since this design is often more convenient than the random-sampling design. When there is an underlying latent heterogeneity, Epstein et al. ([2002] Am. J. Hum. Genet. 70:886-895) showed that it is possible to get unbiased or consistent estimation of population parameters under ascertainment adjustment, but Glidden and Liang ([2002] Genet. Epidemiol. 23:201-208) showed in a simulation study that the resulting estimates are highly sensitive to misspecification of the latent components. To overcome this difficulty, we consider a heavy-tailed model for latent variables that allows a robust estimation of the parameters. We describe a hierarchical-likelihood approach that avoids the integration used in the standard marginal likelihood approach. We revisit and extend the previous simulation, and show that the resulting estimator is efficient and robust against misspecification of the distribution of latent variables. 相似文献
995.
Al-Eisa A Naseef M Al-Hamad N Pinto R Al-Shimeri N Tahmaz M 《Pediatric nephrology (Berlin, Germany)》2005,20(12):1781-1785
Over an 8-year period (January 1996 to December 2003), a total of 171 patients below the age of 15 years were diagnosed with chronic renal failure. The mean incidence rate of CRF in Kuwaiti children was found to be 38.2 per million children per year, with a peak incidence of 55 per million children per year. While the mean age at diagnosis was 33±12 months (range: 1 month to 15 years), the male:female ratio was 2.7:1. Etiological factors for chronic renal failure included congenital urological malformation (61.9%), chronic glomerulopathies (5.2%), hereditary nephropathies (21%), multi-system disease (0.5%), chronic pyelonephritis (without VUR) (4.6%), tumors (0.6%), ischemic renal disease (1.1%) and unknown etiology (1.7%). Thirty percent of patients reached end-stage renal disease within a mean of 18 months following diagnosis. The overall mortality before reaching ESRD was reported to be 4%. Kuwait has one of the highest incidence and prevalence rates of CRF in children. It is likely that genetic and hereditary factors are the cause of these high rates. 相似文献
996.
Sagittal laxity in vivo after total knee arthroplasty 总被引:1,自引:0,他引:1
Ishii Y Matsuda Y Ishii R Sakata S Omori G 《Archives of orthopaedic and trauma surgery》2005,125(4):249-253
Introduction A stress arthrometry study of 77 knees undergoing total knee arthroplasty was performed to determine the difference in anteroposterior (AP) laxity between posterior cruciate ligament (PCL)-retaining (PCLR) and PCL-substituting (PCLS) prostheses using the Genesis I TKA.Materials and methods Fifty-three knees had PCLR and 24 had PCLS prostheses. The selected patients had successful arthroplasties after a minimum follow-up of 5 years. AP laxity was measured with a KT-2000 arthrometer (Medmetric, San Diego, CA, USA) using standard protocols.Results At 30° of flexion, there was no statistical difference in anterior (PCLR: 4.7 mm, PCLS: 4.5 mm), posterior (PCLR: 1.1 mm, PCLS: 0.7 mm), or total (PCLR: 5.8 mm, PCLS: 5.3 mm) displacement. At 75°, significant differences were seen in both anterior (PCLR: 3.3 mm, PCLS: 2.3 mm) and total (PCLR: 4.8 mm, PCLS: 3.4 mm) displacement (p=0.001 and p=0.009, respectively), although there was no statistical difference in posterior displacement (PCLR: 1.5 mm, PCLS: 1.1 mm).Conclusion The above values are considered the suitable degree of AP laxity in total knee arthroplasty for a satisfactory clinical outcome 5–9 years after surgery. The PCL in a PCLR prosthesis and the central tibial spine and femoral cam in a PCLS prosthesis might play comparable roles in determining the laxity in the posterior direction in these prostheses. 相似文献
997.
An ambispective observational study in the safety and efficacy of posterior colporrhaphy with composite Vicryl-Prolene mesh 总被引:1,自引:0,他引:1
There is increasing evidence to show that the use of surgical meshes reduces recurrence rates of hernia repair and anterior vaginal wall prolapse. The aim of this study was to determine the safety and efficacy of posterior colporrhaphy with mesh in patients with posterior vaginal prolapse. An ambispective observational study involving 90 patients was conducted with retrospective chart review and prospective subjective and objective assessments at the end of a 1-year study period. Apart from 2 of 90 (2.2%) minor hematoma incidents, there was no other major perioperative morbidity. Prevalence of common prolapse complaints of vaginal lump sensation, constipation, defecation difficulty and dyspareunia all improved significantly postoperatively (p<0.001). Surgical correction was achieved in 27 of 31 (83.9%) at 6 months and beyond. There was no mesh infection but minor vaginal mesh protrusion was found in 7 of 90 (7.8%) patients at 6–12 weeks and 4 of 31 (12.9%) patients at 6 months and beyond. All these were treated easily with trimming without the need of mesh removal. We conclude that posterior colporrhaphy with mesh is effective in treating posterior vaginal prolapse in short term.Editorial Comment: This study reflects the authors experience in using a Vicryl-Prolene mesh, Vypro II, for treatment of rectocele in 90 patients. No serious operative or postoperative complications occurred. The most common minor complication was vaginal mesh protrusion, with a 9 of the 90 being found with this problem; all but 1 of these were resolved with a simple clinic procedure. In a group of 31 patients followed for at least 6 months, the authors note a 16% recurrence rate of rectocele. In a questionnaire given after the surgeries, comparing pre-op and post-op symptoms, 63–79% of the respondents felt improved, depending on the symptom. The authors feel that vaginal colporrhaphy with Vicryl-Prolene mesh will prove to be more efficacious than the existing popular approaches, including site-specific defect repair. Clearly, randomized controlled studies with longer follow-up comparing this method with other colporrhaphy techniques will be needed to validate this assumptionAn erratum to this article can be found at 相似文献
998.
Joel Wilbush 《Maturitas》1982,4(3):195-205
Though on questioning, women everywhere would probably admit to subjective sensations, known to be associated with climacteric physiological changes, few actively complain of any discomfort these produce. ‘Climacteric symptoms’ are confined to the West. Their absence elsewhere has hitherto been explained by the stress-free-climacteric women enjoy in most other cultures. The rewards of middle life in these cultures are, however, generally limited to women who have raised sons. Others are as liable to stress as Western women. This article suggests that the absence of climacteric symptoms among them is because middle-life stress is not associated in these cultures with illness but is expressed in practical social counteraction.The expression of climacteric stress in medical terms also depends on the manner the climacteric is reached and its general relationship to the menstrual history. The onset of the climacteric tends to have a much higher profile when families are limited, a social custom almost confined to the West. Avoidance of pregnancy and promiscuity also result in troublesome morbid changes at this time. In fact it was these which first brought climacteric women to doctors. As this occurred when, coincidentally, care of the sick became an important aspect of Western culture, the welding of climacteric disturbances and medicine became inevitable.Biologically ‘worthless’, a climacteric woman is regarded as ‘nothing’ in most cultures. Her social standing depends entirely on her sons. Childless women have, however, evolved various compensatory strategems. They manage to obtain social children or, at times, even profit by their very worthlessness. The climacteric expression resembling the menopausal syndrome most, in non-Western countries, is the almost universal fear, throughout the southern and eastern Mediterranean, that a husband may discover the climacteric sterility of his wife and marry a second young and fertile woman. Nonetheless neither this syndrome, nor other behavioral disorders at this time, utilize the physiological sensations of the climacteric as symptoms. 相似文献
999.
The specific activities of N-acetyltransferase (EC 2.3.1.5) were examined in several regions of rat brain of both sexes at various times after birth. The enzyme activity increased with development in whole brain, hippocampus, midbrain, cerebellum and the remainder of brain, peaking around 36 days of age. Lineweaver-Burk plots indicated linear kinetics for N-acetyltransferase in dialyzed supernatant and ammonium sulfate precipitates from the newborn rat brain, whereas enzyme preparation further purified by Bio Gel yielded biphasic kinetics. These data remain consistent with the possibility that there are two forms of N-acetyltransferase in rat brain even from birth. 相似文献
1000.
The current distribution of bipolar electrodes implanted into the scala tympani of the cat cochlea was investigated using a two-electrode masking technique. Two electrode masking is a non-invasive technique which requires two electrically independent electrodes and relies upon the forward masking of the electrically evoked brainstem response to a probe stimulus by that of a preceding test stimulus. The technique was described in terms of a model, which enabled an approach for estimating the scala tympani length constant to be established. Model results have shown good agreement with electrophysiological results. Application of the model confirmed the scala tympani length constant within the basal turn of the cochlea to lie between 3 and 4 mm. 相似文献