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41.
On the day before birth, rat fetuses respond to an intraoral infusion of milk with a stretch response that resembles the behavior of suckling pups at the nipple. Unlike the postnatal response, which occurs coincident with milk ejection, the fetal stretch occurs 3-5 min after milk infusion. Measurement of fetal heart rate (HR) is useful as a predictor of the fetal stretch response. Expression of the stretch response was preceded by a reduction in HR variability and a transient episode of bradycardia. Fetuses that did not stretch showed a delayed reduction in HR variability and no evidence of HR deceleration. Systematic changes in fetal HR may be indicative of changes in fetal state associated with milk infusion and the stretch response.  相似文献   
42.
Recent studies of mortality from motor neurone disease (MND) in Sweden have demonstrated rising levels of mortality from the disease, especially amongst older age groups. Case-control investigations have suggested that certain environmental factors are significantly related to variations in mortality from the disease, and are associated with a probable individual susceptibility to MND. This study applies an innovative epidemiological technique to longitudinal and cohort analysis of Swedish mortality from MND during the period 1961 to 1990. Survival modelling shows that a subpopulation susceptible to MND exists in Sweden, as has been demonstrated in other countries. The increased life expectancy of the Swedish population since 1961 has resulted in more of that susceptible population living to the ages at which MND is expressed, explaining the majority of the increase in mortality from the disease. However, environmental factors may play a role in accelerating the course of MND and may affect the timing of death within the susceptible sub-population.  相似文献   
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Differential mood changes following basal ganglia vs thalamic lesions   总被引:3,自引:0,他引:3  
Patients with computed tomographic scan-verified unilateral lesions in the basal ganglia or thalamus were examined for the presence of poststroke mood disorders. Patients with left-sided basal ganglia lesions (mainly in the head of the caudate nucleus) showed a significantly higher frequency and severity of depression, as compared with patients with right-sided basal ganglia or thalamic (left- or right-sided) lesions. Results suggest that damage to biogenic amine pathways and/or frontocaudate projections may play an important role in the modulation of mood.  相似文献   
47.
Abnormalities of copper in Gilles de la Tourette syndrome   总被引:1,自引:0,他引:1  
The Gilles de la Tourette syndrome is a disorder whose etiology and pathogenesis are little understood. The number of biochemical abnormalities described in this disorder is minimal. Ten of a total of 80 patients were found to have an abnormally low serum copper. A report is presented on two patients who consented to further detailed investigation and in whom copper radioisotope studies were carried out. Both exhibited abnormalities of copper handling, in that we observed an abnormally fast disappearance of copper from the plasma and an abnormally slow uptake by the liver. The rates of intestinal absorption and urinary excretion were normal. We did not identify an abnormal site of sequestration of the metal in the body.  相似文献   
48.
Over the past 20 years there has not only been a substantialincrease in indicators of alcoholrelated harm, but also an increasein professional and public awareness of alcohol problems andthe need to prevent them. Sadly, however, much of this awarenessof the need for prevention has resulted in little more thanrather desultory calls for more education. From my ‘pointof view’ it is time to shift further some of the emphasesin the debate aboust alcohol, education and action.  相似文献   
49.
The spatial distribution of twitch and tonic fibres in a snake muscle one myofibre thick (ventral costocutaneous) has been investigated. It was found that small groups of like fibres were favoured at the expense of larger groups when compared with sequences generated by a computer in which fibres were distributed randomly. The number of times that like fibres occurred next to one another was used as another measure of their spatial distribution. The number of adjacencies of like fibres was less than the expected number of adjacencies determined both by random sequences and by probability theory. The expected number of adjacencies determined by means of random sequences and a priori probability theory were almost identical. This dispersion of like fibres may reflect processes that occur during muscle development and may have functional implications.  相似文献   
50.
Despite the widespread conservative management of breast cancer, the pathologists' examination of these specimens is far from uniform. Pathologists sample margins differently, and even disagree on what constitutes a positive margin. This variability in the pathologic examination of the lumpectomy creates tremendous problems in analyzing the existing literature on the importance of positive margins. Herein is a discussion of the available data on the significance of margin assessment. We furthermore suggest a practical approach to examining margins with an emphasis on a functional orientation of the specimen with respect to the nipple. Only by adopting a uniform system of margin assessment can we begin to critically evaluate the importance of positive margins in segmental resections of the breast.  相似文献   
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