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1.
Osteonecrosis after arthroscopic meniscectomy is a rare postoperative complication. The precise etiology as well as the specific pathomechanism are unknown. There are only case reports in the literature about postarthroscopic osteonecrosis; large series with long-term follow-up are missing. Differential diagnosis between postarthroscopic osteonecrosis and primary osteonecrosis already present before arthroscopy but undiagnosed is only possible by stage-dependent imaging. This study evaluates the current status of knowledge about postarthroscopic osteonecrosis.  相似文献   
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PURPOSE: Remifentanil is a new, short-acting opioid that is similar pharmacodynamically to currently available opioids but differs in its pharmacokinetics. In the present study, we compared the use of remifentanil with the use of meperidine during intravenous conscious sedation for third molar surgery. PATIENTS AND METHODS: Forty patients who were scheduled for the removal of impacted third molars were randomly assigned to undergo 1 of 2 intravenous conscious sedation techniques. For both groups, 50:50 nitrous oxide oxygen were administered via nasal hood, and midazolam was titrated to Verril's sign. Twenty patients each then received either remifentanil 0.05 microgram/kg/min or meperidine 50 mg. Both patients and surgeons were blinded to the narcotic that was used. Blood pressure, heart rate, and oxygen saturation were determined before sedation and every 5 minutes during surgery. Recovery was measured using serial Trieger tests every 5 minutes after surgery. Patient and surgeon satisfaction of the quality of sedation was measured with a visual analog scale. RESULTS: Peak heart rate (91 beats/min for remifentanil vs 107 beats/min for meperidine, P <.01) and peak systolic blood pressure (131 mm Hg for remifentanil vs. 142 mm Hg for meperidine, P <.05) were significantly lower for the remifentanil group. Although there was a trend toward increased surgeon satisfaction with remifentanil (86 of 100 with remifentanil vs. 73 of 100 with meperidine), it was not found to be statistically significant. Likewise, other physiologic parameters were not found to be statistically significant. CONCLUSIONS: The lower peak heart rate and systolic blood pressure levels indicate that remifentanil may allow for less fluctuation in cardiovascular parameters. This could prove beneficial in patients with cardiovascular compromise.  相似文献   
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The modulation of drug metabolising enzymes by Masheri extract (ME) and Benzo(a)Pyrene [B(a)P] was studied in male Sprague Dawley rats fed different dietary protein levels. Two groups of 21 days old male Sprague Dawley rats were put on a high protein diet (SHP) with 20% Casein, and a low protein diet (SLP) with 3% Casein semisynthetic based diets for 12 weeks. The SLP fed animals showed lower basal levels of the Phase I activating enzymes viz. Cytochrome P450, Benzo(a)Pyrene hydroxylase, Benzphetamine demethylase and Phase II glutathione detoxification system viz. Glutathione (GSH) and Glutathione-S-transferase. ME and B(a)P treatment significantly depleted the glutathione detoxification system in the SLP group whereas an opposite effect was observed in the SHP group. Interstingly, ME and B(a)P treated rats in the SLP group showed a higher percent increase in the hepatic and pulmonary Phase I enzyme activities than those observed in the treated ME/B(a)P treated SHP rats. Furthermore, both ME and B(a)P significantly decreased the hepatic pool of vitamin A while a concomittant increase in that of vitamin C was observed.  相似文献   
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A glycolipid (J001X) isolated from the membrane proteoglycans of a non-pathogenic strain of Klebsiella pneumoniae was developed to bind selectively to macrophages. A scintigraphic technique could thus be developed and applied to an experimental model of lung berylliosis. Six baboons were injected intratracheally with a beryllium metal suspension. Three to 24 months later, they were submitted to both an anatomical and a functional respiratory evaluation. Two baboons were explored at the early stage of alveolitis and four baboons at a more advanced stage characterised by a granulomatous disorder. Scintigraphy was performed using J001X labelled with 99mtechnetium administered as an aerosol. In the six baboons, conventional imaging techniques (chest x ray film, computed tomography scan, gallium scintigraphy), failed to show either any lung abnormality or mediastinal lymph nodes consistent with beryllium disease. In the two recently contaminated baboons, J001X scintigraphy showed a well defined parenchymal fixation facing the contaminated lobe. In the four baboons who were at a more advanced stage of berylliosis, J001X fixation was always focused paratracheally without any significant involvement of the lung parenchyma. The subcarinal and laterotracheal lymph nodes seen at necropsy corresponded to J001X scintigraphic fixations. In conclusion, when compared with conventional techniques such as chest x ray film, computed tomography scan, magnetic resonance imaging, and gallium scintigraphy, J001X scintigraphy has proved its ability to detect occult lesions in experimental berylliosis in baboons. By comparison with gallium scintigraphy, scintigraphy with J001X appears to have superior sensitivity and can be performed in four hours.  相似文献   
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Sir, A 4-year-old boy presented with oedema and weight gain of 5kg. There had been no preceding infections, vaccinations ormedication. The family history includes the mothers mesangioproliferativeglomerulonephritis. Laboratory results showed decreased albumin (13 g/l) concentration.Calculated glomerular filtration rate was 125 ml/min/1.73 m2and the  相似文献   
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Anterior cervical discectomy and fusion (ACDF) may be considered to be the gold standard for treatment of symptomatic degenerative disc disease within the cervical spine. However, fusion of the segment may result in progressive degeneration of the adjacent segments. Therefore, dynamic stabilization procedures have been introduced. Among these, artificial disc replacement by disc prosthesis seems to be promising. However, to be so, segmental motion must be preserved. This, again, is very difficult to judge and has not yet been proven. The aim of the current study was to first analyse the segmental motion following artificial disc replacement using a disc prosthesis. A second aim was to compare both segmental motion as well as clinical result to the current gold standard (ACDF). This is a prospective controlled study. Twenty-five patients with cervical disc herniation were enrolled and assigned to either study group (receiving a disc prosthesis) or control group (receiving ACDF, using a cage with bone graft and an anterior plate.) Radiostereometric analysis was used to quantify intervertebral motion immediately as well as 3, 6, 12 and 24 weeks postoperatively. Further, clinical results were judged using visual analogue scale and neuro-examination. Cervical spine segmental motion decreased over time in the presence of disc prosthesis or ACDF. However, the loss of segmental motion is significantly higher in the ACDF group, when looked at 3, 6, 12 and 24 weeks after surgery. We observed significant pain reduction in neck and arm postoperatively, without significant difference between both groups (P > 0.05). Cervical spine disc prosthesis preserves cervical spine segmental motion within the first 6 months after surgery. The clinical results are the same when compared to the early results following ACDF.  相似文献   
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