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101.
102.
O'Brien MF Connolly SS Kelly DG O'Brien A Quinlan DM Mulvin DW 《Irish journal of medical science》2004,173(1):23-26
Background Patients with prostate cancer with a pre-operative prostate-specific antigen (PSA) τ;15ng/ml who undergo radical retropubic
prostatectomy (RRP) generally do not have a good outcome, yet may have organ-confined cancer and should be offered the option
of surgery.
Aim To assess the outcome of patients who underwent RRP with a pre-operative PSA ≥ 15ng/ml.
Methods Thirty-four patients, mean pre-operative PSA: 25.46ng/ml (15.03–76.6) and mean Gleason score: 6.4 (5–9) were assessed.
Results Two groups were identified. Group I: 41% (14/34) have no biochemical recurrence to mean follow up of 58 months (30–106).
Mean PSA: 18.8ng/ml (15.03–25.84). Mean Gleason score: 6.1 (5–7). Clinical stage: T1c in 80%. No patient had seminal vesicle
or lymph node involvement. Group II: 59% (20/34) have biochemical recurrence or died (3) from their disease to mean follow
up of 66 months (36–98). Mean PSA: 28.9ng/ml (15.28–76.6). Mean Gleason score: 6.7 (5–9). Clinical stage: T1c in 25%. Eleven
patients had seminal vesicle (8) involvement or positive lymph nodes (3) or both (2).
Conclusion RRP seems feasible in patients whose pre-operative PSA is between 15 and 25ng/ml with stage T1c, Gleason score ≤ 7 and negative
lymph node frozen section. 相似文献
103.
How do human observers estimate the location, form, and color of objects? Accurate estimation is challenging because the light arriving at the eyes depends not only on object properties, but also on the spectra and spatial layout of the light sources (Nassau, 1983; Foley et al., 1990). How well the visual system separates illuminant and object properties to achieve a stable representation has traditionally been studied under the rubric of color and lightness constancy. Most previous work used very simple stimuli, typically a few diffusely illuminated surfaces arranged perpendicular to the line of sight. Over the past several years, however, there has been an evident increase of interest in expanding the conceptualization of this area to incorporate effects that emerge only for complex, typically three-dimensional, scenes. The current issue features papers that represent various manifestations of this interest. One line of research investigates how the three-dimensional layout of a scene affects the perception of lightness and color. Although the current work has long-standing antecedents (e.g. Mach, 1886/1959; Hochberg and Beck, 1954; Gilchrist, 1980), methodological advances in i) experimentation with real illuminated objects (e.g. Brainard et. al, 1987; Rutherford and Brainard, 2002; Ripamonti et al., 2004; Robilotto and Zaidi, 2004), ii) the use of sophisticated graphics simulations (e.g. Yang and Maloney, 1999; Fleming, Dror, & Adelson, 2003; Boyaci, Maloney, & Hersh, 2003; Delahunt and Brainard, 2004), iii) the design of hybrid systems that combine real objects with image-based graphics and video projection (Ling and Hurlbert, 2004), and iv) psychophysical procedures (Maloney and Yang, 2003; Obein, Knoblauch, & Vienot, 2004) have opened the door for systematic exploration of a wider range of phenomena. Recent papers include work on how well vision compensates for changes in surface orientation (Boyaci et al., 2003; Ripamonti et al., 2004), how effectively it discounts inter-reflections among nearby surfaces (Bloj, Kersten, & Hurlbert, 1999; Doerschner, Boyaci, & Maloney, 2004; Delahunt and Brainard, 2004), and how the visual system effectively estimates the spectral properties and spatial layout of the illuminant in three-dimensional scenes (Kraft & Brainard, 1999; Yang & Maloney, 1999; Boyaci, Maloney, & Hersh, 2003; Bloj et al., 2004; Boyaci, Doerschner, & Maloney, 2004; Khang and Zaidi, 2004). The second thread that leads to papers in the current issue is a focus on the functional utility of color and lightness perception -- the idea that these percepts inform us about the properties of objects rather than those of light spectra. This focus resulted in a renaissance of research in color constancy over the past two decades, with particular progress being made in the development of computational models that explore how, in principle, object surface properties can be estimated from image data. As with the experimental lines, early work focused on simple scene geometries (for reviews see Hurlbert, 1998; Maloney, 1999) but consideration has recently expanded to three-dimensional configurations (Adelson and Pentland, 1996; Yang and Maloney, 1999; Bell and Freeman, 2001; Dror, Willsky, & Adelson, 2004) Of particular interest has been the elaboration of purely computational formulations into parametric models of human performance (e.g. Brainard Brunt, & Speigle, 1997; Brainard Kraft, & Longere, 2003; Boyaci et al., 2003; Doerschner et al., 2004; Boyaci et al., 2004; Bloj et al., 2004), tests of how well the visual system exploits image information identified in computational studies (Yang and Maloney, 2001; Delahunt and Brainard, 2004; Smithson and Zaidi, 2004), investigations of how well the visual system recovers perceptual correlates of material properties other than diffuse surface reflectance, such as gloss and translucency (Lu, Koenderink, & Kappers, 2000; Fleming et al., 2003; Pont & Koenderink, 2003; Obein et al., 2004), as well as how geometric aspects of surface reflectance interact with the perception of shape (Fleming et al., 2003). 相似文献
104.
Desai MM Gill IS Goel M Abreu SC Ramani AP Bedaiwy MA Kaouk JH Matin SF Steinberg AP Brainard J Robertson D Sung GT 《Journal of endourology / Endourological Society》2003,17(5):283-293
BACKGROUND AND PURPOSE: The search for the perfect urinary bladder substitute continues. Despite their inherent limitations, intestinal segments remain the commonest material for bladder reconstruction. The ureter, with its transitional epithelium, may be the ideal tissue to augment the bladder. Ikeguchi et al reported the feasibility of chronic ureteral balloon expansion by open surgery (J Urol 1998;159:1665). Herein, we propose a completely minimally invasive approach to balloon overdilate a segment of juxtavesical ureter incrementally and to use this in-line tissue-expanded ureteral patch to augment the bladder laparoscopically. MATERIALS AND METHODS: In five female pigs, a novel ureteral expansion balloon device (Microvasive, MA) was inserted percutaneously and advanced antegrade into the juxtavesical ureter. The device has two channels: one for balloon inflation and the other for draining the kidney. After progressive ureteral expansion over a 3- to 4-week period, laparoscopic augmentation ureterocystoplasty was performed. Animals were euthanized at 15 days (N = 1), 1 month (N = 1), 2 months (N = 1), and 3 months (N = 2). RESULTS: Percutaneous balloon device placement was technically successful in all five cases (mean operating room time 52 minutes). The mean volume of the tissue-expanded ureter at 1, 2, and 3 weeks was 12.9 cc, 60.3 cc, and 171.8 cc, respectively. Laparoscopic augmentation ureterocystoplasty with (N = 3) or without (N = 2) concomitant subtotal cystectomy was technically successful in all five cases without any open conversion. The mean operative time was 126.5 minutes, and the mean blood loss was 29 mL. Postoperative complications consisted of one case each of pyelonephritis and ureteral stricture. At autopsy, the mean capacity of the bladder was 574 mL, and the P(ves) at maximum capacity was 14 cm H(2)O. Histologic examination of the tissue-expanded ureter revealed regenerated transitional epithelium and muscle hypertrophy. CONCLUSIONS: Chronic ureteral tissue expansion can be carried out safely and efficaciously. The expanded tissue is thick, healthy, and vascular, with histologic features of normal transitional epithelium and muscle hypertrophy and hyperplasia. This expanded ureteral tissue can be used to augment the bladder with laparoscopic techniques. Such augmented bladders do not show significant shrinkage and possess urodynamic characteristic of normal capacity and normal compliance over a follow-up of 3 months. 相似文献
105.
This article presents a brief review of the effects of inhaled corticosteroids on growth in children with asthma. All currently
available inhaled corticosteroids, where there is adequate data, have been shown to cause significant growth suppression in
children in a dose-dependent manner. It is now apparent that there are differences in the growthsuppressive effects of different
corticosteroids. Recent evidence confirms that the growth-suppressive effects are short lived and that, at conventional doses,
inhaled corticosteroids do not affect final attained adult height. 相似文献
106.
107.
Vivek Jaswal MCh Shyam K. S. Thingnam MCh Vikas Kumar MCh Lipi Uppal DM Dheemta Toshkhani MD 《Journal of cardiac surgery》2020,35(5):1152-1155
Congenital aneurysmal dilatation of coronary artery with coronary cameral fistula is rare in childhood. We report an even rarer association of congenital right coronary artery aneurysm and right coronary artery to right ventricle fistula with bicuspid pulmonary valve stenosis and an intact ventricular septum in a 3-year-old child. 相似文献
108.
109.
110.
美国宾夕法尼亚州立大学的2位科学家在性染色体进化变异机制的研究上取得进展。研究发现,Y染色体比X染色体的演化速率快得多,这将导致Y染色体上的基因急剧丢失,如此,Y染色体将会完全消失,人类的传宗接代将受威胁。 相似文献