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101.

Aim

To compare the biomechanical properties of a newly proposed technique, utilizing intramedullary nailing and compression bolts, for the osteosynthesis of intra-articular proximal tibial fractures with meta–diaphyseal comminution, with modern and conventional plating techniques.

Methods

Fifteen left tibia 4th generation composite Sawbones models (in 3 groups of 5 for each technique) with identically reproduced type VI Schatzker tibial plateau fractures, including meta–diaphyseal dissociation, were used. Three different techniques of osteosynthesis were tested: (a) a new technique that combines intramedullary nailing and compression bolts, (b) internal fixation with a single lateral locking plate and (c) internal fixation with dual buttress plating technique. The model-device constructs were successively subjected to 500 N, 1000 N and 1500 N load levels with five cycles applied at each level on both articular compartments and a final load cycle to failure. Four parameters were recorded for each technique: the average reversible or irreversible displacement in vertical subsidence, the horizontal diastasis of the intra-articular fracture, the average passive construct stiffness and the load to failure.

Results

The new intramedullary nailing technique provided rigid intra-articular osteosynthesis being statistically similar to dual buttress plating for subsidence at medium and higher load levels. At the same time the proposed technique provided statistically equivalent stiffness values to the single lateral locking plate incarnating the rational of biologic fixation. Average load to failure was 1611 N for single lateral locking plates, 2197 N for intramedullary nailing and 4579 N for dual buttress plating. The single lateral locking plate technique had the worse results in interfragmentary displacement while dual buttress plating was superior in stiffness from the other 2 techniques. The mode of failure differed between techniques, with collapse of medial plateau occurring exclusively in the single lateral locking plates group.

Conclusion

The proposed new technique of intramedullary nailing and compression bolts demonstrates a flexural behaviour similar to single lateral locking plates, which complies with the terms and benefits of biological fixation, while at the same time maintains a rigid intra-articular stability similar to the stiff dual buttressing plating technique.  相似文献   
102.
103.

Aim-Background

Ambulatory surgery has become the standard method of care for elective operations in many countries. Nevertheless, day surgery in Greece is far from being established as the modality of choice when performing specific operations. The aim of this study was to evaluate the safety and feasibility of day case surgery in selected operations, as well as patient satisfaction.

Methods

Patients were selected last year over a period of twelve months to undergo operations in the setting of ambulatory surgery. Selection criteria were related to social and medical factors; among others, these included the presence of an accompanying adult, elective surgery, and age under 75 years. We performed 142 operations including laparoscopic cholecystectomies, hernia repair and treatment of perianal diseases. Anaesthetic methods comprised general anaesthesia, local anaesthesia and Transversus Abdominis Plane (TAP) block.

Results

No major complications were recorded for any of the selected surgeries, nor any readmissions. The average cost for the total amount of surgeries was reduced by 40%. This cost reduction was mainly due to the limited use of abdominal drains, restricted preoperative examinations and strict anaesthetic protocol. All patients declared satisfaction with the treatment modality that was offered to them.

Conclusions

Following careful and methodic patient selection, day case surgery can reduce the cost of hospitalization and provide patient satisfaction, in addition to being both achievable and safe.  相似文献   
104.
The aim of this in vitro study was to evaluate the performance of various contemporary detection tools at incipient occlusal caries. Thirty eight freshly extracted posterior teeth with non-cavitated occlusal caries were subjected to clinical examination and coding according to ICDAS criteria (n?=?38). Standardized fluorescence images were taken with VistaProof (Dürr Dental, Bietigheim-Bissingen, Germany). Furthermore, the teeth were calculated with a laser fluorescence pen device (DIAGNOdent pen, Kavo, Biberach, Germany). In all detection methods, assessment of caries was performed twice (with 1-week interval) by two calibrated examiners. Finally, the caries lesions were validated in tooth sections by histological examination. The intra-examiner and inter-examiner kappa coefficient, sensitivity, and specificity were determined for all detection methods at enamel lesions (D1 threshold). Degrees of agreement of each method with the histological status were calculated using receiver operating characteristic statistics and the area under curve (Az values). The kappa intra-examiner/inter-examiner coefficient values (mean?±?SD) were 0.74?±?0.04/0.73?±?0.07, 0.87?±?0.04/0.82?±?0.07, and 0.91?±?0.06/0.83?±?0.08 for clinical examination, DIAGNOdent pen, and VistaProof, respectively. The sensitivity for ICDAS was 0.80–0.86, for DIAGNOdent pen was 0.66–0.75, and for the VistaProof device was 0.97. The specificity for all the detection methods were 0.5 (0.02–0.99). The accuracy value for ICDAS was 0.76–0.81, for DIAGNOdent pen 0.66–0.71, and for the VistaProof device 0.92–0.95. The Az values (mean?±?SD) were 0.431?±?0.187, 0.583?±?0.215, and 0.486?±?0.207 for ICDAS, DIAGNOdent pen, and VistaProof examination, respectively. No significant differences in Az values were noted among the methods. All detection methods were presented with high inter-examiner and intra-examiner agreement. The new VistaProof device showed the best sensitivity, while DIAGNOdent pen demonstrated the worst one. Specificities were the same for all detection methods. Moreover, they presented the same performance in detection of incipient occlusal caries.  相似文献   
105.
106.
Chronic bronchitis (CB) is an indicator of an increased risk of developing COPD, but its symptoms are often underestimated. Demographic and socio-economic conditions might influence its prevalence, reporting and impact. Data from a large epidemiological survey of the French general population were analyzed to determine the burden of CB, the magnitude of under-diagnosis and the influence of age, gender and socio-economic conditions. Altogether, 9050 participants aged 45 years or more provided complete data. The prevalence of symptoms and diagnosis of CB was 3.5% and 3.4%, respectively. CB was associated with impaired health status and activity and, in women, work loss. Among subjects with symptoms of CB, only 28.6% declared a known diagnosis of respiratory disease. Factors associated with symptoms of CB in multivariate analysis were male gender, active smoking, lower income and occupational category: the highest prevalence was observed in manual workers (5.6%) and self-employed subjects (5.2%). The under-diagnosis of CB was more marked in men and subjects of higher socio-economic categories. These results confirm that CB is markedly under-diagnosed in the general population. Socio-economic conditions influence both its prevalence (higher in low categories) and rate of diagnosis (lower in high categories), which should be considered when elaborating prevention and detection campaigns.  相似文献   
107.
The isolation of the aneurysm sac from systemic pressure and its consequent shrinkage are considered criteria of success after endovascular repair (EVAR). However, the process of shrinkage does not solely depend on the intrasac pressure, the predictive role of which remains ambiguous. This brief review summarizes the additional pathophysiological mechanisms that regulate the biomechanical properties of the aneurysm wall and may interfere with the process of aneurysm sac shrinkage.  相似文献   
108.
109.
110.

Zusammenfassung

Hintergrund: Die Auswirkungen einer Schwangerschaft auf die Prognose des Mammakarzinoms werden in der Literatur kontrovers diskutiert. Wir haben eine gepaarte Fall-Fall-Studie konzipiert, in der schwangerschaftsasso-ziierte Mammakarzinom (SAM)-Fälle entsprechend ihres Stadiums, Alters und Jahr der Diagnosestellung mit Mammakarzinom-Patientinnen gepaart wurden. Patientinnen und Methoden: 39 aufeinanderfolgende SAM-Fälle wurden mit 39 prämenopausalen Fällen von Brust-krebs gepaart. Univariate und multivariate Überlebens-analysen mit Anpassung an Stadium, Grad, Östrogen-rezeptorstatus und Alter zum Zeitpunkt der Diagnose wurden durchgeführt. Ergebnisse: Hinsichtlich des Gesamtüberlebens deutete die univariate Analyse auf ein längeres Gesamtüberleben für nicht-SAM-Fälle vs. SAM-Fälle hin. Gleichzeitig war ein fortgeschritteneres Stadium ein Prädiktor für ein kürzeres Überleben. Die multivariate Analyse bestätigte die unabhängige ver-schlechternde Auswirkung einer Schwangerschaft. Inter-essanterweise ergab eine genestete Post-hoc-Analyse der SAM-Fälle Hinweise auf ein kürzeres Gesamtüberleben für das dritte Trimester. Die oben erwähnten Ergebnisse für das Gesamtüberleben konnten desweiteren bei der Untersuchung des rezidivfreien Überlebens reproduziert werden. Schlussfolgerung: Mit ihrem gepaarten Fall-Fall-Design deutet die vorliegende Studie darauf hin, dass Schwangerschaft ein schlechter Prognosefaktor beim Mammakarzinom ist.  相似文献   
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