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991.
DD Maglinte FM Kelvin K Fitzgerald DS Hale JT Benson 《Canadian Metallurgical Quarterly》1999,172(2):439-444
OBJECTIVE: Dynamic cystoproctography was used to determine the frequency of associated urinary, genital, and anorectal abnormalities in women with pelvic floor dysfunction. SUBJECTS AND METHODS: We categorized, by pelvic floor compartments, the symptoms at presentation of 100 consecutive female patients who had been referred for dynamic cystoproctography. We then analyzed the compartment defects seen on dynamic cystoproctography relative to those detected on clinical presentation. RESULTS: Of the 20 patients with symptoms of anterior compartment (urinary) defect, dynamic cystoproctography revealed that 45% had vaginal vault prolapse of more than 50% and that 90% had rectoceles. Of the 45 patients with symptoms of middle compartment (genital) defect, dynamic cystoproctography revealed that 91% had cystoceles, 56% had a hypermobile bladder neck, 82% had rectoceles, 58% had enteroceles, 11% had sigmoidoceles, 20% had rectoanal intussusception, and 16% had anal incontinence. Of the 17 patients with symptoms of posterior compartment (anorectal) defect, dynamic cystoproctography showed that 71% had cystoceles, 65% had a hypermobile bladder neck, and 35% had vaginal vault prolapse of more than 50%. Of the 18 patients with symptoms of defects from a combination of compartments, dynamic cystoproctography revealed that 89% had cystoceles, 56% had a hypermobile bladder neck, 39% had vaginal vault prolapse exceeding 50%, 100% had rectoceles (of which 45% were large), 6% had enteroceles, 6% had sigmoidoceles, 22% had rectoanal intussusception, and 6% had anal incontinence. CONCLUSION: Although patients may present with symptoms that involve only one compartment, a multicompartment prolapse is usually revealed on dynamic cystoproctography. Of the patients with pelvic floor dysfunction, 95% had abnormalities in all three compartments. 相似文献
992.
L Zhang PJ Dailey T He A Gettie S Bonhoeffer AS Perelson DD Ho 《Canadian Metallurgical Quarterly》1999,73(1):855-860
Perturbation of the equilibrium between human immunodeficiency virus type 1 (HIV-1) and the infected host by administering antiretroviral agents has revealed the rapid turnover of both viral particles and productively infected cells. In this study, we used the infusion of simian immunodeficiency virus (SIV) particles into rhesus macaques to obtain a more accurate estimate of viral clearance in vivo. Consistently, exogenously infused virions were cleared from plasma with an extremely short half-life, on the order of minutes (a mean of 3.3 min). This new estimate is approximately 100-fold lower than the upper bound of 6 h previously reported for HIV-1 in infected humans. In select animals, multiple tissues were collected at the completion of each experiment to track the potential sites of virion clearance. Detectable levels of SIV RNA were found in lymph nodes, spleen, lungs, and liver, but not in other tissues examined. However, only approximately 1 to 10% or less of the infused virions were accounted for by the thorough tissue sampling, indicating that the vast majority of the infused particles must have been degraded over a short period of time. Should the rapid clearance of virions described here be applicable to infected patients, then HIV-1 production and thus the number of productively infected CD4(+) T lymphocytes or the viral burst size must be proportionally higher than previous minimal estimates. 相似文献
993.
One of the genes that is up-regulated by thyroid hormone (TH) during Xenopus laevis metamorphosis encodes a type III deiodinase (D3) that inactivates TH. Transgenic X. laevis tadpoles overexpressing a GFP-D3 fusion protein were produced. These transgenic tadpoles had high levels of deiodinase activity and were resistant to exogenous TH added 1 week after fertilization. They developed normally throughout embryogenesis and premetamorphic stages but became retarded in their development late in prometamorphosis when endogenous TH reaches its highest level. Gill and tail resorption were delayed and most of the animals arrested and died. One tadpole completed its metamorphosis without resorbing its tail. These results demonstrate that D3 can modulate the action of TH in vivo, and document the value of the new transgenic method for functional analysis of genes involved in metamorphosis. 相似文献
994.
A case of Ivemark's renal-hepatic dysplasia syndrome is presented. The findings are suggestive of a ductal obstructive process anatomically located at the junction of ducts with the parenchyma. The differential diagnosis includes Meckel syndrome, short rib polydactyly syndromes, and glutaric aciduria type 2. The molecular basis for this syndrome remains unknown. 相似文献
995.
The perceptual GRBAS scale for deviant voice quality (completed with a I parameter: Instability = fluctuation of voice quality over time) was tested in 5 different institutes on 943 voice patients. Each voice was evaluated separately by 2 professionals. The interrater correlation reaches 0.87 for G (grade), 0.70 for R (roughness), 0.69 for B (breathiness) and 0.65 for A/S (asthenicity/strain). Experience with the scale significantly improves the interrater agreement. The intrarater correlation (80 voices; time interval 2-6 months) is systematically slightly stronger than the interrater correlation. Further, GIRBAS/acoustical correlations were investigated on 80 pathological voices, by using the Multidimensional Voice Program (MDVP) of Kay. Principal component analysis allows reduction of 21 MDVP parameters to 5 clinically relevant aspects, with a typical acoustical measurement for each of them. The strongest correlations are found between G and Shimmer/Noise to harmonics ratio, R and Jitter, and B and Shimmer. As tremor and diplophonia are easily identified perceptually and acoustically, it seems useful to add this information respectively to AS and R. The GIRBAS scale seems to be a valuable instrument for clinical practice. 相似文献
996.
Compound A is a degradation product of sevoflurane. Knowledge of the solubility of Compound A, CH2F-O-C(=CF2)(CF3), in blood and other solvents would aid in the definition of its kinetics. Accordingly, we determined solvent/gas partition coefficients of Compound A for saline (0.166 +/- 0.002 [mean +/- SD; n = 4]) and olive oil (20.1 +/- 1.1 [n = 4]). Measurement of solubility in blood was confounded by degradation of Compound A in blood and blood components. If a mixture of 99.3% saline and 0.7% oil provides the solubility equivalent to that possessed by blood (as it does for the parent compound, sevoflurane), then blood solubility and solubility in plasma, albumin, red blood cells, or pure hemoglobin is approximately 0.31. The order of Compound A degradation was human plasma = rat blood > whole human blood >5% human serum albumin = washed human red blood cells (hematocrit 50%) = 5% pure hemoglobin. Presuming a solvent/gas partition coefficient of 0.31, respective approximate times for 50% degradation equaled 2.7, 2.8, 4.6, 9.9, 11.0, and 12 min. The accuracy of these approximations was limited by the need to estimate, rather than determine, the solubility of Compound A in such solvents. Pasteurization (heating to 60 degrees C for 12 h) or pretreatment with N-ethylmaleimide (a compound that reversibly binds to sulfhydryl groups) decreased the degradation rate in plasma. These results suggest that degradation arises, at least in part, from reaction of Compound A with proteins in blood, possibly from covalent reaction of Compound A with protein and/or from an enzymatically mediated reaction. The products of degradation, the binding sites, and the clinical implications of such binding and degradation remain to be determined. 相似文献
997.
998.
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1000.
B Hiley-Young DD Blake FR Abueg V Rozynko FD Gusman 《Canadian Metallurgical Quarterly》1995,8(1):125-141
The impact of childhood victimization and other premilitary factors on warzone abusive violence was examined with 177 Vietnam combat veteran inpatients. Premilitary and military variables were also examined in relationship to postmilitary variables, including violence and PTSD. Statistical analyses showed that none of the premilitary variables predicted warzone violence. High combat exposure did, however, predict warzone abusive violence and PTSD. In addition, participation in warzone violence predicted postmilitary violence to self, spouse, and others. Although high rates of childhood victimization and high levels of combat exposure were found, neither predicted postmilitary violence, criminal activities, drug/alcohol problems, or suicide attempts. Low childhood adjustment ratings and school suspensions predicted adult alcohol abuse and drug abuse, respectively. These findings and their implication for treatment are discussed. 相似文献