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International Journal of Clinical Oncology - The practice of cancer diagnosis disclosure to children has been changed with the times. The regulations of clinical trials in the 2000s might change...  相似文献   
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A 1:1 adduct of methyl sorbate (MS) and 1,3‐di‐tert‐butylimidazol‐2‐ylidene (NHCtBu) initiates anionic polymerization of a nonconjugated polar alkene, allyl methacrylate (AMA) in toluene at ?20 °C. After the monomer is consumed quantitatively using a bulky aluminum Lewis acid, methylaluminum bis(2,6‐di‐tert‐butyl‐4‐methylphenoxide) (MAD), as an additive, successive ring‐closure occurs without highly dilute conditions to give a cyclic poly(AMA) containing α‐terminal MS unit, and an Mn of 8.8 × 103?58.5 × 103 with a narrow molecular dispersity index (Mw/Mn = 1.14–1.37). The lack of a need for dilution is due to the fact that an α‐terminal NHCtBu group is acting as the counter cation for the propagating center in the polymerization. From 1H NMR and matrix assisted laser desorption/ionization (MALDI‐TOF) mass spectra, combined with transmittance electron microscope (TEM) observation of a synthesized poly(AMA) with longer alkyl side chains prepared via a thiol‐ene click reaction, it is concluded that once the monomer is consumed, nucleophilic attack at the neighboring methine of the α‐terminal NHCtBu residue by the propagating anionic center causes ring‐closing to cyclic poly(AMA).  相似文献   
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PURPOSE: This study evaluated the bone volume, height, and width that can be obtained in alveolar ridge augmentation using titanium mesh and autogenous bone particles in patients with cleft lip/palate. PATIENTS AND METHODS: Subjects were 15 patients with cleft lip/palate requiring tertiary bone graft for implant therapy. Computed tomography (CT) scans were taken before removing the mesh, from 1 to 21 months after bone grafting. Forty-three reconstructed images corresponding to the positions for implant placement were selected for this study. The percent defect filled with bone (%BONE), defined as the percentage of newly formed bone in the space created by the mesh, was measured for image analyses. In linear analyses, 4 parameters were used: increased bone height (IBH), percent increased bone height (%IBH), increased bone width (IBW), and percent increased bone width (%IBW). Factors influencing the quantitative data and the clinical courses of placed implants were also explored. RESULTS: The average %BONE was 91.1%. IBH averaged 4.4 mm, whereas %IBH averaged 88.5%. IBW averaged 4.6 mm, whereas %IBW averaged 86.4%. Little correlation was present between the quantitative data and patient age, or time interval. A significant correlation was identified between the data for span of the grafted area and %BONE (correlation coefficient value = -0.36). However, the diminishing rate was very low. No implants were lost postoperatively. CONCLUSIONS: Alveolar ridge augmentation with titanium mesh and autogenous bone particles from the anterior iliac crest has very high predictability as a preimplant procedure in patients with cleft lip/palate.  相似文献   
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OBJECTIVE: It is well described that unilateral pelviureteric junction obstruction (PUJO) is a benign condition, because the dilatation resolves spontaneously and the function does not decrease in most of the kidneys. However, there is exceptional PUJO that requires emergent treatment in neonatal periods. The aim of this article is to report the urological emergency and management in neonates with PUJO. MATERIALS AND METHODS: Nine children (seven boys and two girls) with PUJO who underwent neonatal emergent treatment during the last 13 years were reviewed. Renal function was evaluated according to decay curve of serum creatinine (SCr) levels corresponding to gestational age (GA) at delivery. Physical examination, ultrasonographic monitoring, and chest and abdominal plain radiographs were repeated in each neonate. RESULTS: Eight patients were detected prenatally. In five patients, multicystic dysplastic kidney (MCDK) was demonstrated on the contralateral side. Three patients underwent percutaneous puncture of fetal hydronephrosis. Decrease of amniotic fluid was evident in three fetuses. Indications for emergent treatment included mass effect from hydronephrosis in three patients, renal dysfunction in five, and severe urinary tract infection in one. During neonatal periods, a percutaneous nephrostomy tube was placed in seven, and open nephrostomy in one with anorectal malformation. Repeated punctures of the dilated renal pelvis were done in one patient. Renal function after pyeloplasty was stable in eight patients, while it was moderately decreased in one who was associated with oligohydramnios in utero. CONCLUSION: Indications for emergent treatment in neonates with PUJO included mass effect from giant hydronephrosis, renal dysfunction and severe urinary tract infection. At birth, respiratory and circulatory conditions must first be stabilized. In neonates with hydronephrosis of the solitary kidney or severe bilateral PUJO, serial SCr should be monitored to evaluate renal function. Decrease of amniotic fluid suggested renal functional compromise that would not recover after urological management.  相似文献   
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OBJECTIVES: We reviewed the results of surgical treatment for children with ureterocele, especially addressing the importance of the lower urinary tract reconstruction. METHODS: We present medical records of 91 children with ureterocele (31 with the intravesical type, and 60 with the ectopic type) treated during the last 14 years. As the initial treatment, we carried out transurethral incision of the ureterocele (TUI). In patients with persistent reflux, breakthrough urinary tract infection (UTI), or signs of bladder outlet obstruction due to a collapsed cele wall, we recommended that patients undergo lower urinary tract reconstruction irrespective of the renal function involved in ureterocele. The average follow-up period was 5 years (ranging 1 year and 6 months to 14 years). RESULTS: Transurethral incision of the ureterocele was carried out as the initial treatment on 68 patients (75%). A total of 34 patients (21 intravesical [68%] and 13 ectopic [22%]) were followed medically after TUI alone. Reconstruction of the lower urinary tract was carried out in 59 patients (65%). Nephroureterectomy combined with bladder level reconstruction was carried out in four children with single system and non-functioning kidney. Follow-up voiding cystourethrography showed that only one girl had reflux, which disappeared after the first follow-up examination. Postoperative UTI occurred in 12 patients (20%) with ectopic ureterocele. Voiding dysfunction was suspected in eight patients. CONCLUSION: We believe that the primary objective for patients with ureterocele, especially of the ectopic type, is to reconstruct the original pathology of the lower urinary tract that may give rise to reflux, obstruction, or abnormalities of urination. Although surgery at the bladder level can be challenging, the lower urinary tract reconstruction successfully corrects the vesicoureteral reflux and bladder outlet pathology under a cosmetically acceptable incision.  相似文献   
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OBJECTIVES: Lateral biopsies are thought to have a better cancer detection rate compared with standard sextant biopsies. This study aimed to determine whether lateral peripheral zone biopsies in Japanese men who underwent transrectal ultrasound-guided prostate biopsies provided a significantly higher cancer detection rate than sextant biopsies. METHODS: Between 1999 and 2004, data were collected from 461 men who underwent prostate biopsy and had enough data regarding the performance of lateral biopsies for statistical analysis. There were two categories in this study: (i) patients who underwent sextant prostate biopsies; and (ii) patients who underwent sextant biopsies plus lateral biopsies. RESULTS: Prostate cancer was detected in 141 (30.6%) of 461 patients. It was detected in 24 (22.2%) of 108 patients who underwent sextant biopsies and 117 (33.1%) of 353 patients who underwent sextant plus lateral biopsies. Lateral biopsies were not associated with a statistically higher rate of positive biopsy findings; however, we found a significantly higher ratio of patients with positive findings in those with prostate specific antigen (PSA) levels 10 ng/mL (one of 71, 1.4%) among those who had positive cores only in lateral biopsy samples (P < 0.0001). CONCLUSIONS: Lateral biopsies did not show a significantly higher detection ratio of prostate cancer compared to sextant biopsies. However, lateral biopsies were more effective than sextant biopsies in patients with lower PSA levels. Our findings might be useful for the establishment of biopsy strategies to detect prostate cancer, especially in patients with lower PSA levels.  相似文献   
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