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71.

Background

In daily clinical practice, it is essential to properly evaluate the postoperative sliding distance of various femoral head fixation devices (HFD) for trochanteric fractures. Although it is necessary to develop an accurate and reproducible method that is unaffected by inconsistent postoperative limb position on radiography, few studies have examined which method is optimal. Therefore, the purpose of this study is to prospectively compare the accuracy and reproducibility of our four original methods in the measurement of sliding distance of the HFD.

Methods

Radiographs of plastic simulated bone implanted with Japanese proximal femoral nail antirotation were taken in five limb postures: neutral, flexion, minute internal rotation, greater external rotation, and flexion with external rotation. Orthopedic surgeons performed five measurements of the sliding distance of the HFD in each of the flowing four methods: nail axis reference (NAR), modified NAR, inner edge reference, and nail tip reference. We also assessed two clinical cases by using these methods and evaluated the intraclass correlation coefficients.

Results

The measured values were consistent in the NAR method regardless of limb posture, with an even smaller error when using the modified NAR method. The standard deviation (SD) was high in the nail tip reference method and extremely low in the modified NAR method. In the two clinical cases, the SD was the lowest in the modified NAR method, similar to the results using plastic simulated bone. The intraclass correlation coefficients showed the highest value in the modified NAR method.

Conclusions

We conclude that the modified NAR method should be the most recommended based on its accuracy, reproducibility, and usefulness.  相似文献   
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The effects of ethanol on gastric vasculature in isolated vascularly perfused rabbit stomach was investigated. The isolated stomach was perfused with Krebs-Henseleit solution containing 3% dextran bubbled with 95% O2 and 5% CO2 at a rate of 12 ml/min. After mixture and perfusion of 10 mM to 400 mM of ethanol, perfusion pressure and endothelin-1 concentration in effluent from gastric vasculature were measured. Perfusion pressure and endothelin-1 concentration in effluent increased in a dose-dependent manner with increasing ethanol concentrations. In conclusion, the data suggest that ethanol may stimulate the release of endothelin from gastric vasculature and may cause gastric ischemia due to vasoconstriction resulting in acute gastric mucosal injury.  相似文献   
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PurposeThe interface between the transmucosal portion of endosseous implants surface and the connective tissue is characterized by fibroblast-rich barrier tissue, which is important for the long-term stability and maintenance of the implant. This study investigated the effect of cell adhesion on focal adhesion kinase (FAK) protein and on gene expression over a 72-h culture period. Fibroblast-like cells were cultured on anodized-hydrothermally treated commercially pure titanium with nanotopographic structure (SA-treated c.p.Ti) surfaces.MethodsMurine fibroblast-like NIH/3T3 cells were cultured for 10–72 h on c.p.Ti, anodic oxide (AO) c.p.Ti, and SA-treated c.p.Ti disks. Cell morphology was analyzed using scanning electron microscopy (SEM). Cytoskeletal structure and FAK protein localization were analyzed using confocal laser scanning microscopy (CLSM). FAK mRNA levels were analyzed using real-time quantitative RT-PCR.ResultsSEM and CLSM showed increased NIH/3T3 cell adhesion with time, and actin filaments oriented parallel with the filopodium-like extensions on all disks. Filopodium-like extensions were bound tightly to the nanotopographic structure surface of cultures on SA-treated c.p.Ti, and especially at 72 h. FAK protein was localized along cellular extensions on SA-treated c.p.Ti and the expression of FAK mRNA was significantly higher on these disks than on c.p.Ti and AO c.p.Ti after 72 h (P < 0.05).ConclusionsNIH/3T3 fibroblast-like cells have the capacity to adhere to SA-treated c.p.Ti as a transmucosal portion of implant surface material and express focal adhesion molecules, which may play a key role in the maintenance of a mucosal tissue barrier  相似文献   
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BackgroundJapan and the United States (US) have different cultures of caregiving including differences in family structure and social programs that may influence caregiver strain. Differences in caregiver strain between regions in Japan and in the US have not been investigated in patient–spouse dyads in PD.ObjectivesTo compare caregiver strain in spouses of PD patients between Yamagata, Japan and Maryland, US. Correlations between caregiver strain and patient/spousal variables are also examined.MethodsIn Yamagata and Maryland, spouses of patients with PD completed questionnaires assessing caregiver strain. Patients and spouses completed scales assessing mental health, and medical co-morbidity. PD severity and disability were assessed with the Unified Parkinson's Disease Rating Scale and the Schwab and England Activities of Daily Living Scale. Results in the two regions were compared with Chi-square and Student's t-tests. Relationships between caregiver strain and patient/spousal variables were analyzed with univariate correlations and multivariate regression.Results178 Spouse–patient pairs were assessed. The level of caregiver strain in PD did not differ between Yamagata, Japan and Maryland, US despite differences in demographics and social support programs in the two regions. Yamagata spouses reported physical, time and financial constraints, while Maryland spouses reported more emotional distress. In both regions, spousal depression was a significant contributor to caregiver strain.ConclusionDifferent approaches to reduce caregiver strain will likely be necessary in Yamagata and Maryland since the contributing factors to caregiver strain are influenced by differences in culture and social supports in each country.  相似文献   
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The recent increase of pertussis in young adults in Japan is hypothesized to be due in part to waning protection from the acellular pertussis vaccine. While a booster immunization may prevent an epidemic of pertussis among these young adults, little is known about the safety and immunogenicity of such a booster with the diphtheria, tetanus, and acellular pertussis vaccine (DTaP), which is currently available in Japan. One hundred and eleven medical students with a mean age of 19.4 years were randomly divided into 2 groups of 55 and 56 subjects and received, respectively, 0.2 or 0.5 ml of DTaP. Immunogenicity was assessed by performing the immunoassay using serum, and the geometric mean concentration (GMC), GMC ratio (GMCR), seropositive rate, and booster response rate were calculated. Adverse reactions and adverse events were monitored for 7 days after vaccination. After booster vaccination in the two groups, significant increases were found in the antibodies against pertussis toxin, filamentous hemagglutinin, diphtheria toxoid, and tetanus toxoid, and the booster response rates for all subjects reached 100%. The GMCs and GMCRs against all antigens were significantly higher in the 0.5-ml group than in the 0.2-ml group. No serious adverse events were observed. Frequencies of local reactions were similar in the 2 groups, although the frequency of severe local swelling was significantly higher in the 0.5-ml group. These data support the acceptability of booster immunization using both 0.2 and 0.5 ml of DTaP for young adults for controlling pertussis. (This study was registered at UMIN-CTR under registration number UMIN000010672.)  相似文献   
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