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821.
822.
R.M. Post P. Gold D.R. Rubinow J.C. Ballenger W.E. Bunney F.X. Goodwin 《Life sciences》1982,31(1):1-15
This review highlights that essentially all of the recently discovered putative central nervous system (CNS) peptides and other peptide substances are measurable in human cerebrospinal fluid (CSF). Preliminary evidence also suggests that peptides in CSF may have an active regulatory role in relation to CNS function and behavior. Even if this is not the case, CSF peptides may prove to be a useful indirect marker of CNS peptide function and metabolism. Alterations in peptides have been reported in neurological and psychiatric illness, pain symptoms and their treatment, symptoms such as anxiety, and following treatment with CNS active drugs such as carbamazepine. CSF methodologies provide a strategy for the study of the interaction of classical neurotransmitters and peptide substances and their relationship to neural function and behavior in man. Assessment of peptides in CSF may supplement post mortem studies of peptide levels and receptor distribution and help lead to new diagnostic and treatment approaches in neuropsychiatric disorders. 相似文献
823.
David G. Post 《Animal behaviour》1981,29(2):357-374
Quantitative data on the ways in which adult yellow baboons (Papio cynocephalus) distribute their time among various activities are presented. Baboons spend approximately three-quarters of their time feeding or moving. Interseasonal variability in the proportions of time spent feeding and socializing is statistically significant, as are individual differences in the proportions of time spent feeding and moving. Although males and females spend approximately equal proportions of time in each of the activity states, the distributions of the durations of activity bouts show significant intersexual differences in central tendency and dispersion that are consistent with a model of intersexual differences in overall foraging strategies. Consistent diurnal patterns are conspicuously absent, and the relationship between this finding and other ecological variables is discussed. 相似文献
824.
825.
Summary Light microscopic autoradiography was performed subsequent to injection of tritiated amino acids into various parts of the amygdaloid body of the rat. Evidence is provided for two hitherto unreported projections of the amygdala: from the medial amygdaloid nucleus to the contralateral premamillary nuclei and from the central amygdaloid nucleus to the mesencephalic central grey. The functional implications of these findings are discussed. 相似文献
826.
The epidermal melanocyte system of the chimpaneze was studied by the combined skin-splitting DOPA, and electron microscopic techniques. It is very similar to man. There are DOPA-positive epidermal melanocytes in all body regions regradless of the degree of macroscopic skin pigmentation or hirsutism. Furthermore, as in man, but in contrast to rodents, chimpanzee skin contains a very high level of melanocytes in the epidermis; approximately 3,320+/-350 per square millimeter skin. Chimpanzee melanosomes are long, wide, and fully melanized. In keratinocytes, these organelles are individually dispersed in all body regions, regardless of the degree of skin color, as is true for other mammalian species with large melanosomes. 相似文献
827.
828.
Free Na131 I and 131I-Albumin were injected in the cisterna magna of rhesus monkeys. The dynamics of descent into the spinal subarachnoid space and transport out of the cerebrospinal fluid were determined by gamma scintigraphy. 131I-Albumin moved slowly caudally, reaching the sacral CSF in three hours. Free Na131I was rapidly absorbed locally and did not descend. When its transport out of cerebrospinal fluid was inhibited by the addition of unlabeled isotonic Na I, 131I descended slowly at a rate parallel to that of tagged albumin. Injection of Na131I in hypertonic solutions caused immediate descent. Two minute periods of tumbling activity caused rapid movement of Na131I and 131I-Albumin into the lumbar spinal fluid. Na131I dynamics may serve as a model for other molecules actively transported out of cerebrospinal fluid, such as 5-hydroxy-indoleacetic acid; descent into caudal spinal fluid may depend on the degree of efflux from cerebrospinal fluid and on the animal's activity. 相似文献
829.
830.
A. Post 《BioControl》1962,7(3):257-262
Zusammenfassung In einem Hochstamm-Obstgarten und in einer jungen Spindelanlage in der Provinz Zeeland wurde der Einfluss verschiedener Kulturmassnahmen
(Bodenbehandlung, Düngung, Schnitt und der chemischen Bek?mpfung) auf die Entwicklung sch?dlicher Milben- und Insektenarten,
insbesondere der phytophagen MilbeMetatetranychus ulmi
Koch untersucht.
In beiden Versuchsanlagen zeigte sich ein sehr deutlicher Zusammenhang zwischen dem physiologischen Zustand der Obstb?ume
und der Populationsentwicklung vonM. ulmi. Zwischen der Populationsdichte der Milbe und dem Gesamtstickstoffgehalt der Bl?tter wurde eine positive Korrelation beobachtet.
FürBryobia rubrioculus (Scheuten) wurde keine entsprechende Korrelation bemerkt. Die phytophagen MilbenEotetranychus pomi
sep. undBrevipalpus oudemansi
Geyskes erreichten die gr?ssten Populationsdichten in der unbehandelten Parzelle mit niedrigem Gesamtstickstoffgehalt der Bl?tter.
In den ungespritzten Parzellen bestand auch eine positive Korrelation zwischen der Populationsdichte vonM. ulmi und ihren Predatoren. Dennoch vermochte die relativ hohe Anzahl von Predatoren in der Parzelle mit Bodenbehandlung, Düngung
und Schnitt die Populationsdichte vonM. ulmi nicht bis unter das sch?dliche Niveau zu reduzieren.
Ausserdem zeigte sich, dass die chemische Bek?mpfung nicht nur die Predatorenpopulationen herabsetzt, sondern auch den physiologischen
Zustan der Futterpflanze verbessert.
Die h?chsten Populationsdichten vonAphis pomi
Degeer undEriosoma lanigerum (Hausm.) wurden ebenfalls in den Parzellen mit Bodenbehandlung, Düngung und Schnitt beobachtet, obwohl dort die Anzahl der Parasiten
und Predatoren relativ gross war.
Diese Untersuchungen haben ergeben, dass der physiologische Zustand des Obstbaumes von wesentlicher Bedeutung für den aussegew?hnlichen
Anstieg der Milben- und Aphidenpopulationen ist.
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