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31.
We have studied the human thoracolumbar fascia by using antiserum against neurofilament protein (NFP) and S-100 protein to identify sensory nerve fibers and their endings. Seven surgical specimens from 7 patients were studied with light microscopy. In addition to free nerve endings, two types of encapsulated mechanoreceptors (Ruffini's and Vater-Pacini corpuscles) were identified. These findings support the hypothesis that the thoracolumbar fascia may play a neurosensory role in the lumbar spine mechanism.  相似文献   
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Existing literature suggests that one of the effects of treatment based on prolonged speech is increased durations of acoustic segments. However, the external validity of the data concerned may be questioned because the data were not based on spontaneous speech samples and were gathered from subjects with unknown treatment histories. With this in mind, the present investigation used young clients with no history of treatment based on prolonged speech and obtained pretreatment and posttreatment acoustic measures from spontaneous speech samples. Acoustic measures showed no significant posttreatment increases in durations of acoustic segments. However, for the acoustic measure of vowel duration and a measure of articulation rate, posttreatment speech samples showed significantly reduced variability. The potential theoretical and practical relevance of these findings is discussed.  相似文献   
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Segregation analysis of breast cancer in families can provide the logical basis and the specific genetic models for mapping and identifying genes responsible for human breast cancer. Patterns of breast cancer occurrence in families were investigated by complex segregation analysis. In a sample of 1579 nuclear families ascertained through a population-based series of probands, an autosomal dominant model with a highly penetrant susceptibility allele fully explained disease clustering. From the maximum-likelihood Mendelian model, the frequency of the susceptibility allele was 0.0006 in the general population, and lifetime risk of breast cancer was 0.82 among susceptible women and 0.08 among women without the susceptibility allele. Inherited susceptibility affected only 4% of families in the sample: multiple cases of this relatively common disease occurred in other families by chance. The same genetic models, with higher gene frequency, explained disease clustering in an extended kindred at high risk of breast cancer. Evidence for a highly penetrant, autosomal dominant susceptibility allele for breast cancer in a high-risk family and the general population suggests that high-risk families can serve as models for understanding breast cancer in the population as a whole.  相似文献   
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The acute effects of monoamine oxidase inhibitors L-deprenyl (0.5-5.0 mg/kg), clorgyline (1.0-10.0 mg/kg), and milacemide (100-400 mg/kg) on the behavior of adult male squirrel monkeys were examined during brief social separations beginning 60 min after subcutaneous drug administration. All three drugs selectively reduced the rate of calling during social separation at doses which did not affect time spent in locomotion, nor the frequency of vigilance-checking. Deprenyl and milacemide, but not clorgyline, produced concurrent decreases in locomotion at the higher doses tested. At threshold doses, clorgyline, but not deprenyl or milacemide, increased call duration and decreased call peak frequency compared to vehicle control values. Plasma levels of MHPG were decreased by an optimal dose of clorgyline but not by deprenyl or milacemide, indicating that substrate specificity was maintained at the drug doses employed. We conclude that different MAO substrates mediate different aspects of vocal and nonvocal behavior in adult male squirrel monkeys.  相似文献   
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