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91.
For monitoring the changes in intracellular free Ca2+ concentration ([Ca2+]i), we developed a simple system combining a fluorescence microscope, an image intensifier, a video-camera, a cathode ray tube display and a photodiode, employing quin2 as a Ca2+ indicator. We recorded increases of the fluorescence intensity due to [Ca2+]i rises, when high K+ medium, neurotransmitter and Ca2+ ionophore were applied to the single cells of nervous system origin in culture. The present system is capable of simultaneous detection of the [Ca2+]i changes from multiple separate cells.  相似文献   
92.
PURPOSE: This study evaluated the bone volume, height, and width that can be obtained in alveolar ridge augmentation using titanium mesh and autogenous bone particles in patients with cleft lip/palate. PATIENTS AND METHODS: Subjects were 15 patients with cleft lip/palate requiring tertiary bone graft for implant therapy. Computed tomography (CT) scans were taken before removing the mesh, from 1 to 21 months after bone grafting. Forty-three reconstructed images corresponding to the positions for implant placement were selected for this study. The percent defect filled with bone (%BONE), defined as the percentage of newly formed bone in the space created by the mesh, was measured for image analyses. In linear analyses, 4 parameters were used: increased bone height (IBH), percent increased bone height (%IBH), increased bone width (IBW), and percent increased bone width (%IBW). Factors influencing the quantitative data and the clinical courses of placed implants were also explored. RESULTS: The average %BONE was 91.1%. IBH averaged 4.4 mm, whereas %IBH averaged 88.5%. IBW averaged 4.6 mm, whereas %IBW averaged 86.4%. Little correlation was present between the quantitative data and patient age, or time interval. A significant correlation was identified between the data for span of the grafted area and %BONE (correlation coefficient value = -0.36). However, the diminishing rate was very low. No implants were lost postoperatively. CONCLUSIONS: Alveolar ridge augmentation with titanium mesh and autogenous bone particles from the anterior iliac crest has very high predictability as a preimplant procedure in patients with cleft lip/palate.  相似文献   
93.
Phenytoin-induced gingival overgrowth is a recognized side effect in many cerebral palsy patients using diphenyl hydantoin for the control of seizures. Severe gingival overgrowth in these patients can affect normal masticatory function, lead to poor occlusal development, and compromise esthetics. This report addresses the complex nature of treating phenytoin-induced gingival overgrowth in a mentally retarded 20-year-old female patient. For this patient, full-mouth gingivectomy procedure was performed under general anesthesia in a single session. Post operative follow-up was uneventful. This article discusses major indications, contraindications, and protocols to be followed for periodontal surgical procedures done under general anesthesia.  相似文献   
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In this new radioimmunoassay system for determination of amatoxins in urine and plasma, a novel chemical approach is used for antigen and 125I-tracer production, based on a detoxified alpha-amanitin derivative (aldoamanitin). Total assay time, including data processing, is less than 100 min. The lowest detectable concentration is 1 microgram/L for urine, 0.1 microgram/L for plasma. In the clinically significant range, within-run CVs are less than 8%. This new 125I-based assay is a significant improvement over existing 3H technology in terms of speed, precision, and freedom from interference.  相似文献   
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Bilateral cervical lymph node dissection was performed in 71 cases of papillary thyroid carcinoma, considered to be relatively early cases because of mobility, irrespective of the size of tumor or presence of node enlargement. Of these, 33 cases received additional node dissection of the anterosuperior mediastinum through longitudinal sternotomy. The number of lymph nodes examined per subject averaged 89.9, the number of metastatic nodes was 13.8, and metastasis was noted in 88.7% of all cases. Lymph node metastasis tended to be more frequent on the affected side, but was simultaneously scattered over the whole cervical area. As to sites, metastasis of paratracheal nodes on the affected side occurred at a frequency of 66.2%, inferior and superior jugular nodes at 62.0% and 59.0% respectively, pretracheal nodes at 50.7%, and tracheoesophageal nodes at 47.9%. The high incidence of para- and pretracheal nodes suggests that the lymph flow in this direction is of great importance in metastasis. In fact, lymph nodes in the mediastinum, which were directly continuous with these nodes, showed as high as 39.4% metastasis in cases of anterosuperior mediastinal extirpation. This extensive node dissection is considered to be very preferable as at least the agony of survival with carcinoma can be lessened.  相似文献   
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Liver histopathology in clinical Reye syndrome   总被引:1,自引:0,他引:1  
Analysis of the liver histopathology in 19 children with clinical Reye syndrome (RS) revealed that nine had diffuse panlobular steatosis, one giant cell hepatitis, one a mild choledochal cyst with inflammation, two multifocal spotty necrosis and one multiple centrilobular necrosis, the other five being normal. Four of the nine patients with diffuse panlobular steatosis showed microvesicular fatty droplets with central nuclei, which was consistent with findings characteristic for typical RS. Two cases showed a periportal area dominant macrovesicular fatty change, which was highly suggestive for metabolic disorder. In the other three cases, the findings were so variable in terms of the size of lipid droplets and the location of nuclei in hepatocytes that it was not possible to provide any clue for defining a diagnosis. These results confirmed the legitimacy of the diagnostic criteria of RS which included a liver biopsy as one of the mandatory conditions. They also indicated that RS-mimicking clinical pictures can be presented by miscellaneous conditions in which liver histology does not necessarily helpful in establishing definite diagnosis.  相似文献   
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