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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   
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   
96.
The depletion of proteoglycans in cartilage matrix is the beginning of cartilage breakdown. Prostaglandins and related compounds might play an important role in inhibition of cartilage metabolism under arthritic conditions. Prostaglandin endoperoxides, intermediate metabolites of arachidonic acid, are more potent chemical mediators than prostaglandins, but their action can only be demonstrated in cartilage co-incubated with synovial tissue, because they are short-lived and active only within a small restricted space. Human rheumatoid synovialis highly inhibited sulfation of cartilage matrix co-incubated. The inhibition of cartilage metabolism was released by indomethacin added to the co-incubating system, showing its responsiveness to indomethacin. The magnitude of inhibition was time-dependent and substantially greater than that by prostaglandin in cell-free rheumatoid synovial culture media. The results suggest a possible involvement of prostaglandin endoperoxides in potent inhibition of cartilage metabolism under arthritic conditions.  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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