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991.
Somatic response properties were determined for over 1,300 neurons isolated within and near the lateral sulci of unanesthetized and unparalyzed cynomolgus monkeys. Somatic stimuli unequivocally activated the majority of units studied in SII (93%) and in cortical fields surrounding SII: area 7b (65%), the retroinsular field (74%), and the granular insula (76%). No activation other than somatic was seen for SII neurons, and noxious somatic stimulation was rarely required. The SII units almost always responded in a rapidly adapting manner to hair or skin stimulation, but not both; however, the submodality distribution seen in SII varied as a function of peripheral receptor locations. Two small zones within SII contained neurons that responded only if the animal actively interacted with the stimulus. In contrast, one-half of the sample of neurons from area 7b unequivocally responded only to somatic stimulation. Although many neurons in the lateral parts of area 7b were vigorously activated by innocuous tactile stimulation, others demonstrated little association with an identifiable somatic submodality, had sluggish responses, required complex, noxious, visual or other non-somatic stimuli for activation, and had labile response properties and receptive fields. Indeed, the responses of some area 7b neurons suggested a possible relationship with the animal's attention towards or anticipation of a noxious or a novel somatic stimulus. Neurons within the retroinsular cortex (Ri), which receives projections from the posterior nucleus (PO), primarily responded to light tactile stimulation of rapidly adapting skin receptors; less than 3% responded to moderate or high threshold mechanical stimulation. The sensitivity to tactile stimulation in Ri closely resembled the responses of SII neurons. Neurons in the granular insula (Ig) often responded to gentle hair deflection within receptive fields covering large areas of the body. Ig and area 7b were the principle loci within the lateral sulcus that contained neurons responding to noxious stimulation. Owing to the great similarity in the somatic response properties within these areas in the awake and unparalyzed animal, the designation of cortical areas could only be made after correlating the recording sites with connectional and cytoarchitectonic analyses in the same animal. Consequently, previous physiological studies may have attributed to SII some of the response characteristics of neurons in neighboring areas. 相似文献
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J H Cummings W J Branch L Bjerrum A Paerregaard P Helms R Burton 《Nutrition and cancer》1982,4(1):61-66
Stool weight and transit time through the gut were measured in 4 groups of 30 men, aged 50-59 years, randomly selected from populations in urban (Copenhagen) and rural (Them) Denmark and urban (Helsinki) and rural (Parikkala) Finland. These populations exhibited a 3-4 fold difference in risk for large bowel cancer. Mean transit time (37 +/- 1 hours, Copenhagen; 43 +/- 1 hours, Helsinki; 40 +/- 1 hours, Them; 37 +/- 1 hours, Parikkala) was not significantly different among populations, but average 24-hour stool weights (136 +/- 13 g, Copenhagen; 176 +/- 17 g, Helsinki; 169 +/- 16 g, Them; 196 +/- 15 g, Parikkala) were different and had a significant inverse relationship to total large bowel cancer incidence, with larger stool weights being found in the low-risk population. A high proportion of study subjects, especially in Finland, were found to be taking medication or to have a history of gastrointestinal illness, but neither of these variables related to bowel habit. 相似文献
995.
Fetal sex-related differences in maternal serum alpha-fetoprotein during the second trimester of pregnancy 总被引:1,自引:0,他引:1
In an analysis of data gathered from routine maternal serum alpha-fetoprotein screening, we determined that the sex of the fetus is significantly correlated with differences in maternal serum alpha-fetoprotein concentration during the second trimester of pregnancy. Between the fifteenth and nineteenth gestational weeks, the mean maternal serum alpha-fetoprotein level is significantly higher for the male fetus than for the female fetus. There was no difference, however, in the rate of increase in maternal serum alpha-fetoprotein concentration with time between male and female fetuses during the weeks of gestation that were studied. No apparent cause for these observations has been demonstrated. 相似文献
996.
Serum bone Gla protein (BGP) and alkaline phosphatase (AP) activity were compared for the assessment of skeletal status in 11 normal pregnant women, 12 normal women on days 3 and 13 of the menstrual cycle, five postmenopasual women before and after 1 month of treatment with ethinyl estradiol (20 μg/day), five patients with cancer and hypercalcemia during treatment with calcitonin, and one patient with Paget disease during treatment with Plicamycin. BGP and AP correlated with each other only in the pregnant women. In all other circumstances, there was no correlation between these two serum osteoblast products. Furthermore, there were condisitions in which the two measurements became discordant. These studies demonstrate that BGP and AP commonly are dissociated when used as measurements of skeletal status. Although both are osteoblast products, BGP and AP probably reflect different aspects of osteoblast differentiation and function. 相似文献
997.
Acetabular labral tears: evaluation with MR arthrography 总被引:12,自引:0,他引:12
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999.
Burton A. Johnson M.D. J.D. A. Everette James Jr. M.D. J.D. 《Current problems in diagnostic radiology》1979,8(6):1-19
In summary, the physician's duty to inform has been described and discussed. The minority and majority rule have also been defined and analyzed along with the major causes of physician failure and resistance to disclose risks. In a proper physician-patient relationship, informed consent controversy should be rare. A calm, clear, direct and properly documented disclosure of risks of a procedure is the best defense in any jurisdiction. 相似文献
1000.