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31.
32.

Background  

The thrust plate prosthesis (TPP) is a hip prosthesis with metaphyseal fixation to the femur. Because the bone quality is reduced in patients with rheumatoid arthritis, this kind of fixation may have a higher failure rate than conventional stemmed endoprostheses in these patients. The aim of this investigation was to analyze the long-term results obtained with the TPP in patients with rheumatoid arthritis.  相似文献   
33.
While options for operative treatment of leg axis varus malalignment in patients with medial gonarthrosis include several established procedures, such as unicompartmental knee arthroplasty (UKA), total knee arthroplasty (TKA) or high tibial osteotomy (HTO), there has been little focus on a less invasive option introduced more recently: the UniSpacer™ implant, a self-centering, metallic interpositional device for the knee. This study evaluates clinical and radiological results of the UniSpacer™, whether alignment correction can be achieved by UniSpacer™ arthroplasty and alignment change in the first five postoperative years. Anteroposterior long leg stance radiographs of 20 legs were digitally analysed to assess alignment change: two relevant angles and the deviation of the mechanical axis of the leg were analysed before and after surgery. Additionally, the change of the postoperative alignment was determined one and five years postoperatively. Analysing the mechanical tibiofemoral angle, a significant leg axis correction was achieved, with a mean valgus change of 4.7 ± 1.9°; a varus change occurred in the first postoperative year, while there was no significant further change of alignment seen five years after surgery. The UniSpacer™ corrects malalignment in patients with medial gonarthrosis; however, a likely postoperative change in alignment due to implant adaptation to the joint must be considered before implantation. Our results show that good clinical and functional results can be achieved after UniSpacer™ arthroplasty. However, four of 19 knees had to be revised to a TKA or UKA due to persistent pain, which is an unacceptably high revision rate when looking at the alternative treatment options of medial osteoarthritis of the knee.  相似文献   
34.
We have shown that manual stimulation of rat whisker-pad muscles following facial-facial-anastomosis (FFA) restores normal whisking by lowering the proportion of polyinnervated motor endplates. Here we examined whether manual stimulation of the orbicularis oculi muscle (OOM) after FFA would also improve outcome. Blink responses to standardized air puffs were analyzed using video-based motion analysis. Two months after FFA, blink capacity was impaired, as indicated by a largely increased minimum distance between the eyelids after air-puff stimulation compared with intact rats (2.7 +/- 0.4 vs. 0.2 +/- 0.01 mm). Manual stimulation reduced this deficit by a factor of two (1.3 +/- 0.5 mm). The functional improvement after manual stimulation was associated with a 2-fold decrease in the proportion of polyinnervated OOM endplates (21 +/- 10% vs. 42 +/- 10% without manual stimulation, 0% in intact rats). We conclude that manual stimulation is a noninvasive and simple procedure with immediate potential for clinical rehabilitation of eyelid closure following facial nerve injury.  相似文献   
35.
BACKGROUND: The purpose of the study was to analyze the actual injury situation of bicyclists in Germany to create a basis for effective preventive measures. METHODS: Technical and medical data were prospectively collected shortly after the crash at the crash scenes. RESULTS: Included were 4,264 injured bicyclists from 1985 to 2003. Fifty-five percent of the bicyclists were male and 45% were women. The mean age of bicyclists was 52.0 years. The crashes took place in urban areas in 95.2% of the cases, and in rural areas in 4.8% of the cases. Collision opponents were cars in 65.8%, trucks in 7.2%, bicyclists in 7.4%, standing objects in 8.8%, multiple opponents or objects in 4.3%, and others in 6.5%. The mean collision speed was 21.3 km/h. The helmet use rate was 1.7%. Fifty-five percent of bicyclists used bicycle traffic lanes before the crash. The mean Maximum Abbreviated Injury Scale/Injury Severity Score (ISS) was 1.45 of 3.9. The incidence of multiple injuries (ISS>16)/death was 2.0%/1.5%. The ISS/Maximum Abbreviated Injury Scale score was higher in bicyclists without a helmet than in bicyclists with a helmet, and in bicyclists who had not used bicycle traffic lanes than in bicyclists who had used bicycle traffic lanes (t test, p<0.05). CONCLUSION: In bicyclists, head and extremities are at high risk for injuries. The helmet use rate is unsatisfactorily low. Remarkably, two-thirds of the head injuries could have been prevented by helmets. More consequent helmet use and an extension of bicycle traffic lanes for a better separation of bicyclists and motorized vehicles would be simple but very effective preventive measures.  相似文献   
36.
Unicompartmental knee arthroplasty (UKA) has become a frequently used treatment option for anteromedial osteoarthritis (OA) of the knee due to good clinical and functional results. However, serious complications like tibial plateau fractures have been reported. These can be associated with saw cuts during surgery. The purpose of this study was to analyse saw cuts during Sawbone® preparations at instructional unicompartmental knee courses and to identify potential sources of surgical error. One hundred Sawbone® preparations were performed by knee surgeons inexperienced with UKA. Sawing errors during preparation were analysed and quantified. Tibial and femoral errors can occur during preparation. At the proximal tibia three errors can be found: extended vertical cuts (A), extended horizontal cuts (B) and perforation of the posterior cortex. An ascending cut at the posterior femoral condyle (C) is possible during femoral preparation. Errors type A were found at a mean length of 2.4 mm ± 2.3 mm with a maximum value of 10.1 mm. In 18% errors of more than 4.0 mm were found. Type B errors showed an average value of 2.0 mm ± 1.7 mm with maximum values of 7.4 mm. Type C errors were found at a mean of 1.3 mm ± 1.0 mm (maximum value 5.1 mm). Our data showed that in 18% of the cases, vertical cutting errors of more than 4.0 mm occurred in inexperienced surgeons.  相似文献   
37.

Background

The normal human prostate glandular epithelium has the unique function of accumulating high levels of zinc. In prostate cancer this capability is lost as an early event in the development of the malignant cells. The mechanism and factors responsible for the ability of the normal epithelial cells to accumulate zinc and the loss of this capability in the malignant cells need to be identified. We previously reported that Zip1 is an important zinc uptake transporter in prostate cells and is down regulated in the malignant cells in situ along with the depletion of zinc levels. In this report we investigated the expression of two other Zip family zinc transporters, Zip2 and Zip3 in malignant versus nonmalignant (normal and BPH) glands. Zip2 and Zip3 relative protein levels were determined by immunohistochemistry analysis of human prostate tissue sections.

Results

Normal and BPH glandular epithelium consistently exhibited the strong presence of both Zip 2 and Zip3; whereas both transporters consistently were essentially non-detectable in the malignant glands. This represents the first report of the expression of Zip3 in human prostate tissue; and more importantly, reveals that ZiP2 and Zip3 are down regulated in malignant cells in situ as we also had demonstrated for Zip1. Zip2 and Zip3 transporter proteins were localized predominantly at the apical cell membrane, which is in contrast to the Zip1 localization at the basolateral membrane. Zip2 and Zip3 seemingly are associated with the re-uptake of zinc from prostatic fluid.

Conclusion

These results coupled with previous reports implicate Zip2 and Zip3 along with Zip1 as important zinc uptake transporters involved in the unique ability of prostate cells to accumulate high cellular zinc levels. Zip1 is important for the extraction of zinc from circulation as the primary source of cellular zinc. Zip 2 and Zip3 appear to be important for retention of the zinc in the cellular compartment. The down regulation of all three transporters in the malignant cells is consistent with the loss of zinc accumulation in these cells. Since zinc imposes tumor suppressor effects, the silencing of the gene expression for these transporters is a required event for the manifestation of the malignant activities of the neoplastic cells. This now provides new insights into the genetic/molecular events associated with the development of prostate cancer; and supports our concept of Zip1, and now Zip2 and Zip3, as tumor suppressor genes and zinc as a tumor suppressor agent.  相似文献   
38.
39.
Purpose. In patellar tendinopathy, there is anterior knee pain with tenderness of the attachment of the patellar tendon over the lower pole of the patella. The condition is commonly associated with athletic overuse, but we have encountered it in some patients following direct blunt trauma to the anterior aspect of the knee. We describe the history and management of patients with traumatic patellar tendinopathy.

Method. Between April 2000 and August 2006, we managed eight otherwise healthy well trained athletes who developed signs and symptoms compatible with classical patellar tendinopathy after a direct trauma to the anterior aspect of the patellar tendon during sport activity.

Results. The clinical diagnosis of patellar tendinopathy was confirmed clinically and at imaging by MRI and ultrasound scans. Patients responded to conservative or surgical management, in the same way as patellar tendinopathy secondary to overuse.

Conclusion. A single direct traumatic event can lead to chronic tendon problems. Hence, in addition to overuse injury, patellar tendinopathy can follow a direct trauma and exhibit the same clinical features. Further research is required to better understand the pathophysiology of the clinical condition.  相似文献   
40.
The effect of changes in stroke volume on the cross sectional velocity distribution in the mitral orifice during passive mitral inflow was studied in six patients with total atrioventricular block, atrial fibrillation and VVI pacemakers during periods with different heart rates. The time velocity integrals recorded both in the left ventricular outflow tract and at the mitral orifice decreased significantly as the heart rate was increased from 60 to 80 and from 80 to 100 beats per minute. Instantaneous cross sectional flow velocity profiles were constructed by time interpolation of the velocity data from each point in sequentially delayed two dimensional digital ultrasound maps. Each patient had a characteristic cross sectional flow velocity profile in the mitral orifice recorded at the level of the leaflet tips in a four chamber view. The velocity profiles varied between the patients. With increase in heart rate only minimal changes in the flow profiles from individual patients were seen. The maximum velocity through the mitral orifice overestimated the cross sectional mean velocity at the same time by a factor of 1.4–1.9. The maximum time velocity integral overestimated the cross sectional mean by a factor of 1.4–1.8. The observed cross sectional skew varied between patients but did not change significantly with increasing heart rate and decrease in stroke volume.  相似文献   
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