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Jaafar Mouhyi Lars Sennerby Jeanjacques Pireaux Nicolas Dourov Samir Nammour Jack Van Reck 《Clinical oral implants research》1998,9(3):185-194
The purpose of the present study was to analyse clinically failed and retrieved implants prior to and after cleaning by means of scanning electron microscopy (SEM) and X-ray induced photoelectron spectroscopy (XPS) as compared to unused controls. Six different chemical and physical techniques for cleaning of contaminated titanium implants were evaluated: 1) rinsing in absolute ethanol for 10 min, 2) cleaning in ultrasonic baths containing trichloroethylene (TRI) and absolute ethanol, 10 min in each solution, 3) abrasive cleaning for 30 s, 4) cleaning in supersaturated citric acid for 30 s, 5) cleaning with continuous CO2-laser in dry conditions at 5 W for 10 s, 6) cleaning with continuous CO2-laser in wet conditions (saline) at 5 W for 10 s. SEM of failed implants showed the presence of contaminants of varying sizes and XPS showed almost no titanium but high carbon signals. XPS of unused titanium implants showed lower levels of titanium as previously reported, probably due to contamination of carbon which increased with time in room air. Cleaning of used implants in citric acid followed by rinsing with deionized water for 5 min followed by cleaning in ultrasonic baths with TRI and absolute ethanol gave the best results with regard to macroscopical appearance and surface composition. However, as compared to the unused implants the results from an element composition point of view were still unsatisfactory. It is concluded that further development and testing of techniques for cleaning of organically contaminated titanium is needed. 相似文献
13.
Boron neutron capture therapy (BNCT) is a potentially valuable treatment of malignant brain gliomas. A primary requirement for successful BNCT is achieving high local concentration of boron drugs in tumors. Intratumoral injection of liposomes containing boron drug has potential to meet this requirement and could prove to be of significance for BNCT. The brain tissue reaction following the intracerebral injection of a boron drug, BSH, either in solution form or in liposomally encapsulated form, was studied in rats. On histological examination, no evidence of tissue reaction was found after injecting BSH solution, suggesting that high local concentration of BSH was well tolerated. Injection of liposomal BSH was characterized by phagocytic activity at the site of injection, which was regressing by 24 h. Neither group of animals exhibited any signs of abnormal behavior or neurologic deficit. Direct intracerebral injection of BSH liposomes as per-formed in this report could be regarded as tolerable. 相似文献
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Extrapontine and central pontine myelinolysis (EPM/CPM) are rare events in pediatric neurology but can have devastating consequences. They are most commonly associated with rapid correction of hyponatremia but have been reported in other situations as well. This condition is relatively more common in adult neurology, not surprisingly, as alcoholism and associated malnutrition are often predisposing conditions. There have been few case reports in children with regards to this. We describe a 4-year old who presented with focal neurological deficits in the setting of diabetic ketoacidosis and the ensuing underlying osmotic imbalances. The patient made a remarkable recovery with no deficits of note-cognitive or motor. To our knowledge this is the youngest case reported so far of EPM in a child with diabetic ketoacidosis. The history of the condition, early animal experiments, clinicopathologic correlates, previous case reports and other scenarios in which this unusual event can occur are discussed--though the exact pathogenesis of this condition still remains unclear. We hope to bring to the attention of clinicians caring for children in the acute care setting, the importance of gradual correction of serum osmolality to reduce morbidity and mortality. 相似文献
16.
An ankylosed tooth can be suitable for obtaining orthodontic anchorage. However, if such a tooth lacks adequate clinical crown height, the anchorage will not be effective. In those situations surgical luxation or restorative crown augmentation is suggested. This case report is about the restorative treatment of an ankylosed, infraoccluded tooth to enhance the anchorage for forced orthodontic eruption of impacted maxillary canines. A crown augmentation in the form of a modified bilayered (sandwich) restoration using GIC, Composite resin and Silver amalgam on left maxillary first molar (26) was successful in sustaining the anchorage for forced eruption and alignment of impacted canines. 相似文献
17.
C J Buggé S R Gautam L E Parke J T Mason D B Garcia 《Journal of pharmaceutical sciences》1990,79(12):1095-1098
An HPLC method is described for the simultaneous and rapid determination of sulfasalazine (salicylazosulfapyridine) and two of its metabolites, sulfapyridine and N-acetylsulfapyridine, in human serum. The range of quantitation is 0.1 to 12 micrograms/mL for sulfasalazine and sulfapyridine and 0.25 to 12 micrograms/mL for N-acetylsulfapyridine. Serum is mixed with acetonitrile containing the internal standard sulfamethazine and the ion-pairing agent tetraethylammonium chloride. The acetonitrile extract is concentrated and analyzed by HPLC, using a new polymer-based column, and detected by UV spectroscopy at 270 nm. This paper is the first both to describe the simultaneous analysis of all three of the compounds from serum and to present sulfasalazine concentration-time data following oral administration to humans. 相似文献
18.
Radhika Srinivasan Raje Nijhawan Upasana Gautam Pradeep Bambery 《Diagnostic cytopathology》1994,10(4):383-384
A case of primary amyloidosis, initially detected by fine-needle aspiration of the liver, is reported here. Amorphous acellular metachromatic material was seen extracellularly in between the hepatocytic cords compressing them. This material showed typical apple-green birefringence under crossed bipolars after alkaline Congo-red staining proved its amyloid nature. It was resistant to potassium permanganate pretreatment, indicating it to be of the AL type. © 1994 Wiley-Liss, Inc. 相似文献
19.
Jens Toft Birger Hesse Alan Rabøl Steen Carstensen Samir Ali 《European journal of nuclear medicine and molecular imaging》1997,24(4):409-414
Reference data files support the evaluation of myocardial perfusion single-photon emission tomography (SPET). The aim of this study was to create a large reference data base for technetium-99m sestamibi SPET, age and gender matched to the general patient population. One hundred and twenty-eight healthy volunteers (76 males and 52 females) with a likelihood of coronary artery disease of less than 5% underwent rest and maximal exercise99mTc-sestamibi SPET with a 2-day protocol and 180° elliptical rotation. The normalized activity values of99mTc-sestamibi in the inferior wall differed significantly between men and women. Age variations were found for men in the anterior wall. Normalized activity values in all four walls were strikingly similar during rest and stress. Our results suggest that the use of reference files in99mTc-sestamibi SPET requires a gender- and, for males, possibly an age-matched reference population. Different reference files at rest and during stress might not be necessary. 相似文献
20.
C S Pant D K Gupta R C Sharma A S Gautam R M Bhatt 《Indian journal of malariology》1992,29(4):235-239
Frequency of sickle cell in Scheduled Caste and Scheduled Tribe populations was found to be 1.5 and 14.9% respectively, whereas G-6-PD deficiency was 5.9 and 4.2% respectively. Blood group B was dominant in both the communities. A significantly lower frequency of P. falciparum malaria was observed among sicklers. 相似文献