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1.
A series of positron emission tomography scans was made on two monkeys during a 16-month period when they received manganese(IV)oxide by subcutaneous injection. The distribution of [11C]-nomifensine uptake, indicating dopamine terminals, was followed in both monkey brains. The brain distributions of [11C]-raclopride, demonstrating D2 dopamine receptors, and [11C]-l-dopa, as a marker of dopamine turnover, were followed in one monkey each. The monkeys developed signs of poisoning namely unsteady gait and hypoactivity. The [11C]-nomifensine uptake in the striatum was reduced with time and reached a 60% reduction after 16 months exposure. This supports the suggestion that dopaminergic nerve endings degenerate during manganese intoxication. The [11C]-l-dopa decarboxylation was not significantly altered indicating a sparing of [11C]-l-dopa decarboxylation during manganese poisoning. A transient decrease of [11C]-raclopride binding occurred but at the end of the study D2-receptor binding had returned to starting values. The magnetic resonance imaging (MRI) revealed that the manganese accumulated in the globus pallidus, putamen and caudate nucleus. There were also suggestions of gliosis/edema in the posterior limb of the internal capsule. MRI might be useful to follow manganese intoxication in humans as long as the scan is made within a few months of exposure to manganese, i. e. before a reversal of the manganese accumulation.  相似文献   
2.
Infiltrative capacity was found to distinguish separate T leukemia cell lines. Of seven T-cell lines four exhibited capacity to infiltrate Matrigel. Analysis of infiltration was performed at the single-cell level throughout the Matrigel using a depth meter. Further, we examined differences in migration capacity and metalloproteinase production between infiltrating and non-infiltrating T-cell lines. The capacity to infiltrate was not directly correlated to the capacity to adhere to the Matrigel or to migrate on/to extracellular matrix components. It is concluded that infiltration capacity does not simply reflect capacity to migrate but represents a distinct functional property. The production of metalloproteinases and their inhibitors by the separate T-cell lines was analyzed using rt PCR, biosynthetic labelling, zymography, immunoprecipitation and ELISA. All T-cell lines with capacity to infiltrate produced matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) while non-infiltrating cell lines did not express MMP-9. Expression of MMP-1, 2, 3, 10, 14 and 17 showed no correlation to capacity to infiltrate. Analysis of infiltration in the presence of a metalloprotease inhibitor showed an increased number of cells within the gel. This enhancement of infiltration suggests that the function of MMPs and/or their inhibitors in lymphocyte infiltration is more complex than previously thought. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
3.
We compared the efficacy of the Medoff sliding plate (MSP) with 3 other screw-plate systems for fixation of unstable intertrochanteric fractures in a randomized multicenter trial of 569 elderly patients. The MSP has biaxial dynamic capacity along both the neck and the shaft of the femur unlike the other systems, which lack dynamic capacity along the shaft. 268 fractures were operated on with the MSP, and 301 with the dynamic hip screw (DHS), with or without a trochanteric stabilizing plate (DHS/TSP) or with the dynamic condylar screw (DCS). The MSP had recently been shown to the surgeons.The patients in the groups were similar as regards age, domestic situation, preinjury walking ability and type of fracture. We followed the patients clinically and radiographically for at least 1 year. There was no significant difference in walking ability at follow-up or rate of return to home. Fixation failure occurred in 18/268 fractures operated on with the MSP, in 8/238 with the DHS, in 3/49 with the DHS/TSP and in 1/14 with the DCS. The difference in the rate of fixation failure was not statistically significant when the MSP group was compared to the 3 other groups. In 14 of the 18 fixation failures in the MSP group, the biaxial dynamic capacity of the MSP had not been used due to technical errors by surgeons, unfamiliar with the new method. No selection bias was found regarding fracture types in the 2 subgroups of patients with correct or inadequate biaxial dynamization. Extramedullary fixation of unstable intertrochanteric fractures with these implants showed a low failure rate. When using the MSP, biaxial dynamization must be correctly performed.  相似文献   
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Summary Two cases of arrhythmogenic right ventricular dysplasia (ARVD) in siblings are reported. In the boy, 14 years old, the clinical history, ECG, echocardiography, and histopathological findings were consistent with ARVD. Premature ventricular contractions of left bundle branch block (LBBB) pattern were recorded but no ventricular tachycardia (VT). A high titer against mycoplasma and increased concentrations of immunoglobulins were found. Two years after his first admission he died suddenly. Autopsy revealed severe right ventricular (RV) myocardial damage, with fat cell infiltration and collagenous tissue. His sister presented with sustained VT of LBBB pattern 2 years later, at 12 years of age. Vaccination against rubella and signs of upper respiratory illness had preceded the symptoms. During the following 9 days ECGs and serum enzymes indicated the development of left ventricular (LV) infarction. Echocardiography revealed an enlarged RV and a normal LV. After 6 weeks both RV and LV showed akinetic areas and sacculations. We suggest that myocarditis may be a precipitating factor in ARVD, and perhaps the prerequisite for its manifestation.  相似文献   
7.
A randomized study was performed for the comparison of two copper-releasing intrauterine contraceptive devices (IUDs), the Nova-T and the Copper-T-200, simultaneously in Denmark, Finland, and Sweden. Five years' experience demonstrated that Nova-T users had a significantly lower pregnancy rate than Copper-T-200 users. The Pearl index over 5 years was 0.8 for Nova-T users and 2.0 for Copper-T users. The performance and tolerance of the Nova-T were less affected by parity and age than was the performance of the Copper-T. Infections were treated by removal of the device and with antibiotics. The cumulative rate of removals because of infections and suspected infections was below 5 with both devices over 5 years. The copper wire in the Nova-T has a silver core which prevents corrosion-induced fragmentation of the wire. Hence, the effective lifetime of this device is more than 5 years. The results indicate that the Nova-T, which is easy to insert and remove and is associated with a low pregnancy rate and a low medical termination rate, is a real improvement over other IUDs.  相似文献   
8.
Our aim was to compare hemiarthroplasty (HA) and osteosynthesis (OS) in the treatment of cervical hip fractures using matched-pair analysis, especially with regard to different age groups. Data concerning all hip fractures (excluding pathological fractures) at the University Hospitals of Lund in Sweden, where osteosynthesis with LIH hook-pins was used exclusively, and of Oulu in Finland, using mainly cementless Austin-Moore hemiarthroplasty, were registered during 1989-1996 using the same standardized hip fracture forms filled in preoperatively and at 4 months follow-up. Altogether 446 pairs matched for age, sex, place of residence and walking ability at the time of fracture were found. Patients aged 55-80 years seemed to benefit more, with regard to function, from OS than older patients. At 4 months follow-up, 38% of HA and 48% of OS patients lived in their own homes, 16% and 27% were able to walk alone outdoors, and 11% versus 16% were able to walk without any aids, respectively. At 1 year follow-up, mortality was significantly lower among the OS patients, but the reoperation rate was significantly higher. In conclusion, OS is associated with a better function and lower mortality than HA, especially in younger patients, and it is recommended as the primary treatment for cervical hip fractures in patients younger than 80 years and with good ambulatory capacity, whereas the oldest patients can also be safely treated by HA.  相似文献   
9.
A randomized study was conducted simultaneously in three countries to compare the clinical performance of two new IUDs, the Nova-T and Copper-T-200. Forty-four persons, midwives, general practitioners, residents and specialists in obstetrics and gynecology inserted 907 Nova-Ts and 936 Copper-Ts. The pregnancy rate of Nova-T (0.7 at one year) was significantly lower than that of Copper-T (2.2 at one year). No significant differences were observed in other termination rates. The continuation rates were 72.6 for Nova-T and 71.3 for Copper-T-200. The total experience was based on 18,035 woman months of use, with a lost to follow-up of less than 7 per cent for both IUDs.  相似文献   
10.
AIMS: Evaluate nutritional status and fluid and energy intake during the first ten days of hospitalisation in a selection of otherwise healthy patients with a hip fracture. METHODS: A prospective randomised controlled study of 80 patients. Nutritional status was assessed at inclusion. The energy and fluid intake was recorded and calculated daily whilst hospitalised. All patients were given ordinary hospital food and beverage. In the treatment group (n = 40) patients also received intraveneous supplementary nutrition (1000 kcal/day) for three days followed by oral supplementary nutrition (400 kcal/day) for seven days or until discharge. RESULTS: One third of patients were classified as malnourished in both groups. The average daily fluid intake/patient was 1300 ml in the control group compared to 1856 ml in the treatment group (P<0.0001). The average daily energy intake/patient was 916 kcal in the control group compared to 1296 kcal in the treatment group (P = 0.003). The mean difference between actual and needed daily fluid intake was -739 ml in the control group and +27 ml in the treatment group (P<0.0001). Corresponding numbers for energy intake was -783 kcal/day in the control group and -228 kcal/day in the treatment group (P = 0.0003). CONCLUSIONS: Malnutrition is common even in a selection of healthy patients with hip fractures. During hospital stay the fluid and energy intake was considerably lower than that needed in the control group. Supplementary nutritional intake for ten days increased the total fluid and energy intake in the treatment group to near needed levels.  相似文献   
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