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971.
OBJECTIVES: To elucidate brain mechanisms underlying the psychophysical processes to measure pain intensity, pain-related somatosensory evoked potentials (pain SEPs) following painful CO(2) laser stimulation were studied while employing a task to measure intensity of pain on a visual analogue scale (VAS).METHODS: In 12 healthy subjects, 3 kinds of CO(2) laser stimuli, different in intensity as determined by irradiation duration of 40, 60 and 80ms, were randomly delivered to the left hand dorsum at an irregular interval of 4-6s. The subject was requested to assess the intensity of each pain stimulus and point to the VAS scale by moving a pointer held with the right hand according to the subjective feeling of pain sensation (pain intensity assessment (PIA) condition). For the control condition, the subject moved the pointer to the midpoint of the VAS line irrespective of the pain intensity (control motor task condition). Electroencephalograms were recorded from 21 scalp electrodes, referenced to the linked earlobes, and were averaged time-locked to the stimulus onset for each stimulus duration as well as for each task condition.RESULTS: The VAS scores were 2.8+/-0.5/10 for the stimulus of 40ms duration, 4.8+/-0.8/10 for 60ms and 6.1+/-0.9/10 for 80ms, and showed a highly significant positive correlation with the stimulus duration. Following the early components of pain SEPs which were affected by stimulus duration but not modulated by task conditions, a surface-positive peak at latency of 612-642ms was identified exclusively under the PIA condition regardless of the stimulus intensity and was called 'intensity assessment-related potential (IAP)'. The IAP was maximal at the midline parietal area and symmetrically distributed over the scalp. Neither latency nor amplitude of the IAP was significantly different among the 3 different stimulus intensities.CONCLUSIONS: IAP is an event-related potential (ERP) associated with assessment of pain intensity but not influenced by pain intensity itself. From its scalp distribution, it can be assumed that the assessment of pain intensity involves multiple areas in both hemispheres.  相似文献   
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Dye lasers are useful for treating pigmented skin lesions, but their equipment is expensive and bulky. A simple and cheap phototherapy would be acceptable to dermatologists for treating pigmented skin lesions such as nevus of Ota. We investigated as a pilot study whether dermal injection of riboflavin and exposure to near-ultraviolet/visible radiation (ribophototherapy) decreases the dermal pigment of blue nevi which are recalcitrant to laser therapy. The therapeutic efficacy was assessed by comparison of the amount of dermal pigment in hematoxylin-eosin specimens taken before and after treatment. Pigmentation of the nevus became faint to the depth of 1 mm with little noticeable epidermal change after 21 treatments. At the deeper dermis somewhere between 3 and 4 mm from the epidermis, ballooning degeneration of the dermal cells was observed in hematoxylin-eosin specimens. Ribophototherapy is hopeful for treating pigmented skin lesions.  相似文献   
974.
International Ophthalmology - To determine between-method differences in corneal endothelial cell parameters using center and automated methods of non-contact specular microscopy (CellCheck...  相似文献   
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The tumor drainage pathway of a hypervascular liver tumor without fibrous capsule was evaluated histologically and using single-level dynamic CT during hepatic arteriography (CTHA) in a case of sclerosing type of hepatocellular carcinoma. This tumor had a thin corona on CTHA, which represented drainage from the tumor sinusoids to the surrounding liver sinusoids. Additionally, the corona of the hypervascular tumor was thinner without than with the fibrous capsule.  相似文献   
978.
In published reports of naphazoline ingestion, clinical effects are hypertension, bradycardia, pallor, diaphoresis, and respiratory distress. We report three cases of acute pulmonary edema after the intentional ingestion of naphazoline-containing antiseptic first aid liquid. These cases presented with altered mental status, hypertension, bradycardia, and diaphoresis. Chest x-ray on admission revealed acute pulmonary edema. Two cases required mechanical ventilation. All of these clinical effects resolved within 24 hours and the patients were discharged with no sequelae. Since naphazoline stimulates the peripheral alpha-2 adrenergic receptor, we speculate that intense vasoconstriction may have elevated cardiac afterload and left atrial-ventricular blood volume and caused acute pulmonary edema.  相似文献   
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