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21.
Magnesium alloys have been proposed as prospective degradable implant materials. To elucidate the complex interactions between the corroding implants and the tissue, magnesium implants were analyzed in a mouse model and the response was compared to that induced by Ti and by the resorbable polymer polyglactin, respectively. One month after implantation, distinct traces of corrosion were apparent but the magnesium implants were still intact, whereas resorbable polymeric wound suture implants were already fragmented. Analysis of magnesium implants 2 weeks after implantation by energy-dispersive X-ray spectroscopy indicated that magnesium, oxygen, calcium and phosphate were present at the implant surface. One month after implantation, the element composition of the outermost layer of the implant was indicative of tissue without detectable levels of magnesium, indicating a protective barrier function of this organic layer. In agreement with this notion, gene expression patterns in the surrounding tissue were highly similar for all implant materials investigated. However, high-resolution imaging using energy-filtered transmission electron microscopy revealed magnesium-containing microparticles in the tissue in the proximity of the implant. The release of such corrosion particles may contribute to the accumulation of calcium phosphate in the nearby tissue and to bone conductive activities of magnesium implants.  相似文献   
22.
A mixed case of chronic tracheal (syringeal) and pulmonary (lungs and air sacs) aspergillosis was diagnosed in an adult female gyrfalcon (Falco rusticolus). The bird presented with a 4-week history of severe dyspnea, exercise intolerance, depression and reduced appetite. Physical examination revealed slight emaciation. Hematological analysis showed leucocytosis, heterophilia, monocytosis, and thrombocytosis. Radiographic examination showed thickening of the air sac walls and increased radiopacity within the lung field. Caseous granulomatous lesions were observed during tracheoscopy and laparoscopy procedures. Cytological examination of specimens obtained from these lesions demonstrated Aspergillus species, which was isolated in culture and identified as Aspergillus flavus.  相似文献   
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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   
26.

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   
27.
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   
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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   
30.
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   
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