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21.

Purpose

We aimed to propose a practical selection method predicting the easier radical perineal prostatectomy (RPP) cases before the operation.

Methods

Fifty sequential RPP cases were divided into two groups according to the estimated difficulty of the operation (Group I: Easier, Group II: Difficult) which was assessed by using a RPP difficulty scale, constituted by three parameters (operation time, blood loss, and the judgment of the surgeon) each ranging between 1 and 3 points. As the localization parameters, skin-to-prostatic apex (SPAD) and skin-to-prostatic base (SPBD) distances and distance between bilateral ischial tuberosities (ITD) were measured. During suprapubic ultrasonography, a probe-divergence angle (PDA) and prostate volumes (PV) were recorded. These parameters were compared between the groups.

Results

In Group I (n = 29) and Group II (n = 21), the difficulty scores were 4.37 (3–5) and 6.80 (6–9), respectively. Data of age, clinical stages, and findings of digital rectal examination were not different between groups. While SPBD, SPAD, and ITD values were found similar (p > 0.05), PDA and PV were significantly different. PDA was > 45 degree in 21 cases in Group I (72.4 %) and in 7 cases in Group II (33.3 %) (p = 0.011). The mean of PV was 37.4 (20–60) cc and 49.9 (30–75) cc in Group I and Group II, respectively (p = 0.001).

Conclusions

While planning RPP operations, by selecting the prostate cancer cases with a prostate of low volume and localized deeper in the pelvis during suprapubic ultrasonography, urologists may have a chance to perform this technique more easily during the learning period.  相似文献   
22.

Background

There are contrary opinions regarding the surgical treatment of pulmonary hydatid cysts. We report our experience performing a modified version of uncapitonnage surgery, called “saucerization,” for treating pulmonary hydatid cysts.

Methods

A total of 78 patients with pulmonary hydatid cysts were studied regarding their surgery outcome and the complication rate. The procedure used for cyst evacuation depended on whether the cyst had ruptured. If ruptured, cystotomy was done; otherwise, enucleation was preferred. To deal with the residual cavity in an uncapitonnage manner, we removed the thin margins of the pericyst and closed the bronchial openings at the cavity floor. All patients were followed up at least for 6 months.

Results

The intensive care unit stay ranged from 1 to 9 days. Incomplete lung expansion (six patients) was the main postoperative complication followed by wound infection (four patients) and persistent air leak (≥7 days) (one patient). There was one death. Dependence on mechanical ventilation and subsequent septic shock were also observed. The other patients exhibited no complications during the follow-up period.

Conclusions

Our experience demonstrated a low complication rate associated with removing the thin margins of the residual cavity and changing the shape of it into a “saucer.” The results were satisfactory and comparable to the results of other studies on pulmonary hydatid cysts.  相似文献   
23.
Local effect of acetyl salicylic acid (ASA) on peripheral nerve regeneration was studied using a rat sciatic nerve transection model. Forty-five male healthy White Wistar rats were divided into three experimental groups (n = 15), randomly: Sham-operation (SHAM), control (SIL), and ASA-treated (SIL/ASA) groups. In SHAM group after anesthesia left sciatic nerve was exposed through a gluteal muscle incision and after homeostasis the muscle was sutured. In SIL group the left sciatic nerve was exposed the same way and transected proximal to tibio-peroneal bifurcation leaving a 10-mm gap. Proximal and distal stumps were each inserted into a silicone tube and filled with 10 μl phosphate buffered solution. In SIL/ASA group defect was bridged using a silicone tube filled with 10 μl acetyl salisylic acid (0.1 mg/ml). Each group was subdivided into three subgroups of five animals each and were studied 4, 8, and 12 weeks after surgery. Data were analyzed statistically by factorial analysis of variance (ANOVA) and the Bonferroni test for pair-wise comparisons. Functional study confirmed faster and better recovery of regenerated axons in SIL/ASA than in SIL group (p < 0.05). Gastrocnemius muscle mass in SIL/ASA was significantly more than in SIL group. Morphometric indices of regenerated fibers showed that the number and diameter of the myelinated fibers in SIL/ASA were significantly higher than in control group. In immuohistochemistry, location of reactions to S-100 in SIL/ASA was clearly more positive than in SIL group. Response to local treatment of ASA demonstrates that it influences and improves functional recovery of peripheral nerve regeneration.  相似文献   
24.
25.
Before the advent of the Internet, television and film was the only audio-visual medium to which most children were exposed. The risks were primarily limited to children being exposed to sexual and violent materials, the nature of which were known and easy to control. Nowadays, children are surrounded by a variety of digital media and are exposed to different risks, many of which are still unknown. The Internet is fully integrated into children’s daily lives, along with the potential risks. The present study aimed to (i) describe the level of risks children are exposed to, and (ii) test the measurement validity of a total of 45 items assessing nine scales of online risk to children that were adapted from studies carried out in Europe and the United States. The study comprised 420 schoolchildren. The results showed that children were more exposed to ‘unwanted exposure to pornography’ and less to ‘conduct risk’ (e.g., accidental illegal downloading; creating profiles on inappropriate websites). Boys and older children were more exposed to the risks compared to girls and younger children. The study validated five dimensions (inappropriate materials, sexting, contact-related risks, risky online sexual behavior, and bullying/being bullied) assessing online risk to children by using exploratory and confirmatory factor analyses. The study found that scales developed in Europe and the United States are not wholly suitable to an Asian context and needed to be modified. Further investigation to classify online risks to children and offer a solutions to reducing the online risks.  相似文献   
26.
BackgroundIn 2015, the U.S. Soccer Federation banned heading for players aged 10–13.Purpose/QuestionTo assess the change in proportion of children aged 10–13 playing soccer in the US presenting to an Emergency Department (ED) with a concussion in relation to any other injury before and after the ban.MethodsAnalysis was restricted to soccer athletes between 10–13 years that reported to a National Electronic Injury Surveillance System (NEISS) participating hospital ED following injury in 2013–2014 and 2016–2017. Multivariable logistic regression was performed to assess the association between year of injury and concussion diagnosis in relation to other injury diagnosis after adjusting for age, sex, and ethnicity.ResultsConcussion in relation to other injuries showed a significant increase in 2016–2017 when compared to 2013–2014 after adjustment (OR= 1.286, 95%CI = 1.090–1.517).ConclusionsThese results suggest that banning heading may not reduce concussion within this population. However, significant confounders, including increased reporting, were not controlled for.  相似文献   
27.
Achieving good quality of products from plastic injection moulding processes is very challenging, since the process comprises many affecting parameters. Common defects such as warpage are hard to avoid, and the defective parts will eventually go to waste, leading to unnecessary costs to the manufacturer. The use of recycled material from postindustrial waste has been studied by a few researchers. However, the application of an optimisation method by which to optimise processing parameters to mould parts using recycled materials remains lacking. In this study, Response Surface Methodology (RSM) and Particle Swarm Optimisation (PSO) methods were conducted on thick plate parts moulded using virgin and recycled low-density polyethylene (LDPE) materials (100:0, 70:30, 60:40 and 50:50; virgin to recycle material ratios) to find the optimal input parameters for each of the material ratios. Shrinkage in the x and y directions increased in correlation with the recycled ratio, compared to virgin material. Meanwhile, the tensile strength of the thick plate part continued to decrease when the recycled ratio increased. R30 (70:30) had the optimum shrinkage in the x direction with respect to R0 (100:0) material where the shrinkage increased by 24.49% (RSM) and 33.20% (PSO). On the other hand, the shrinkage in the y direction for R30 material increased by 4.48% (RSM) and decreased by 2.67% (PSO), while the tensile strength of R30 (70:30) material decreased by 0.51% (RSM) and 2.68% (PSO) as compared to R0 (100:0) material. Validation tests indicated that the optimal setting of processing parameter suggested by PSO and RSM for R0 (100:0), R30 (70:30), R40 (60:40) and R50 (50:50) was less than 10%.  相似文献   
28.
The demand for natural fiber hybrid composites for various applications has increased, which is leading to more research being conducted on natural fiber hybrid composites due to their promising mechanical properties. However, the incompatibility of natural fiber with polymer matrix limits the performance of the natural fiber hybrid composite. In this research work, the mechanical properties and fiber-to-matrix interfacial adhesion were investigated. The efficiency of methyl methacrylate (MMA)-esterification treatments on composites’ final product performance was determined. The composite was prepared using the hand lay-up method with varying kenaf bast fiber (KBF) contents of 10, 15, 20, 25, 30, 35 (weight%) and hybridized with glass fiber (GF) at 5 and 10 (weight%). Unsaturated polyester (UPE) resin and methyl ethyl ketone peroxide (MEKP) were used as binders and catalysts, respectively. Scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR) were used to examine the effects of MMA-esterification treatment on tensile strength and morphology (tensile fracture and characterization of MMA-esterification treatment) of the composite fabricated. The tensile strength of MMA-treated reinforced UPE and hybrid composites are higher than that of untreated composites. As for MMA treatment, 90 min of treatment showed the highest weight percent gain (WPG) and tensile strength of KBF-reinforced UPE composites. It can be concluded that the esterification of MMA on the KBF can lead to better mechanical properties and adhesion between the KFB and the UPE matrix. This research provides a clear reference for developing hybrid natural fibers, thus contributing to the current field of knowledge related to GF composites, specifically in transportation diligences due to their properties of being lightweight, superior, and involving low production cost.  相似文献   
29.
Poly(2-vinylpyridine-b-methylmethacrylate) coated gold nanoparticles [P(2VP-MMA)-AuNPs] were prepared and characterized by UV-Vis, FTIR, AFM, and zetasizer analysis. Investigation of the potential of the synthesized poly(2-vinylpyridine-b-methylmethacrylate) coated gold nanoparticles [P(2VP-MMA)-AuNPs] for detection of nicotine is the main focus of the current study. P(2VP-MMA)-AuNPs were coated on a glassy carbon electrode (GCE) for electrochemical detection of nicotine by cyclic voltammetry. The effect of molar mass of individual P2VP blocks and total molar mass of the block copolymer is evaluated in the context of an enhanced electrochemical response of the modified GCE for its sensing ability of nicotine in both aqueous and organic media. The electrochemical detection of nicotine is significantly enhanced by modification of the GCE with P(2VP-MMA)-AuNPs.

Poly(2-vinylpyridine-b-methylmethacrylate) coated gold nanoparticles [P(2VP-MMA)-AuNPs] are employed for enhancement of electrochemical response of glassy carbon electrode for nicotine.  相似文献   
30.
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