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1.
Because spitzoid melanoma shares many histopathologic features with Spitz nevus, it is one of the most difficult lesions to diagnose in dermatopathology. Uncertainty exists in the medical literature about how to diagnose melanocytic proliferations including Spitz nevus and spitzoid melanoma. A misdiagnosis of a melanoma as Spitz nevus is one of the most frequent causes of malpractice lawsuits in surgical pathology and dermatopathology. This contribution provides a review of the clinical presentation, histopathology, ancillary studies, treatment, and the differential diagnosis of spitzoid melanoma.  相似文献   
2.
To elucidate the frequency of mutations of the β/A4 amyloid protein precursor (APP) gene in early-onset Alzheimer disease, we designed a mismatched PCR-RFLP that can identify all kinds of missense mutations at codon 717 in addition to the seven kinds of known mutations at exon 17. When we screened mutations at exon 17 utilizing this method and the double missense mutations at exon 16 of the APP gene by PCR-RFLP, no cases revealed mutations of the APP gene among 13 familial and 54 sporadic cases, except one family (OS-1) that had previously been reported and used as a positive control of APP717(Val → Ile). Our results support the hypothesis that mutations in the APP gene are not major causes in early-onset Alzheimer disease.  相似文献   
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Two polymorphic dinucleotide (CA) repeat clones were isolated from cosmids, cCI8-1121 and cCI8-1199, mapped to chromosome 8p11.2-p12.  相似文献   
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Spontaneous action potentials were monitored from multiple sites in the bullfrog atrium using a voltage-sensitive merocyanine-rhodanine dye together with a 100-element photodiode matrix array, and we have assessed the spread of the excitation from the pacemaker. Isochrone curves of conduction were obtained by timing the initiation of the action potential-related optical signals: we constructed maps of the spread. Excitatory waves appeared to conduct radially from the pacemaking area over the atrium, and the conduction velocity in the left atrium exceeded that in the right atrium.  相似文献   
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We examined consistent characteristics behind the trial-to-trial variati on in intrinsic optical imaging of single barrel cortical responses to D 1-whisker movement in 2-5-week postnatal (2-5 W) and adul t (>9-weeks) Wistar rats, and we identified the effective are a of the neural response. The extent/size, configuration and orientation of the intrinsic optical response area varied from trial-to-trial with the same whisker stimulation. We argue that the trial-to-trial variation was due to cortical blood circulation related to the barrel neural activity. Subsequently, interpolating a family of the traces of the optical response area imaged with repeated stimulation for each animal, we extracted a centered circular area from the trial-to-trial response for each animal. Although the trial-to-trial variation decreased gradually with age, the spatial extent of the interpolated response area was consistently about 660 microm in diameter, in agreement with that measured morphologically and/or histochemically. A possible interpretation is that the optically defined area appears to image the actual effective single-barrel response area, as a first approximation. Furthermore, the constancy of the extracted area independent of age suggests that the barrel cortex is, in fact, virtually mature by 2 weeks of age. The extracted area was also nearly independent of the frequency (>/=5 Hz) of whisker movement.  相似文献   
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We traced and identified the ontogenetic expression of neural excitability related to the vagus nerve in the embryonic rat brain stem. Multiple-site optical recordings of neural activities revealed two response areas in the E12 rat brain stem: one corresponding to the dorsal motor nucleus of the vagus nerve, and the other reflecting the activities of sensory nerve fibers. In embryos younger than E11, no optical response was identified, suggesting that excitability of the motoneurons and/or sensory nerve fibers is first generated no later than E12. A contour line map of the neural responses suggested that, in contrast to older embryos, the functional organization of the vagal nucleus is not orderly at the time of the initial expression of neural excitability.  相似文献   
10.
Distribution of Legionella spp. were surveyed two different times in Kinki District, Japan. The first time, eighty six building cooling tower waters were collected from Osaka, Hyogo and Nara Prefecture between April and December, 1987. The second time, thirty five waters were studied from Nishinomiya City in Hyogo Prefecture on July, 1989. BMPA alpha agar plate was used as the isolation medium for the first eighty six samples and MWY agar plate for the second thirty five samples. Legionella were isolated from forty two samples (48.8%) of the first eighty six samples. Three different species of Legionella were isolated simultaneously from one sample and two species from eight samples. L. pneumophila serogroup 1 was the most predominant species. Twenty three samples (65.7%) were positive in culture from the second thirty five samples. Three different species of Legionella were isolated simultaneously from three samples and two species from eleven samples. Legionella anisa was more predominant than L. pneumophila serogroup 1 in this study.  相似文献   
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