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51.
In the Markham Valley of Papua New Guinea, multivariate graphical displays of serological, anthropometric, and dermatoglyphic population structures are compared pursuant to the hypothesis that fingerprints have a slower velocity of evolutionary change and, therefore, are preferable biological markers for prehistorical reconstructions. Samples from nine villages, which represent three geographical and linguistic populations, are plotted in two dimensions using appropriate multivariate techniques for maximally portraying between sample variability. Both the serological and morphometric displays are found lacking in close clusters, which demonstrates a lack of congruence with the shared languages and, presumably, the ethnohistorical origins of the three populations. These discrepancies between biology and prehistory appear to reflect recent environmental and stochastic perturbations. On the other hand, fingerprint displays conform closely to language affiliations, relatively undisturbed by environmental variation and genetic drift. The relative congruence between ethnohistorical affiliation and fingerprint diversity is further corroborated by comparing the three measures of population structure with geographical distances, using partial rank correlations. In terms of explained variance, the level of association with fingerprints is more than twice than with anthropometry, and 13 times greater than with serology. Whereas metric and serological data provide distorted portrayals of known biohistorical relationships among the study populations, fingerprint data mirror these relationships. The theoretical foundations and consequences of this observation are discussed with respect to the broader question of polygenic versus monogenic biological markers. 相似文献
52.
William L. Krinsky Stephen J. Brown Philip W. Askenase 《Experimental parasitology》1982,53(3):381-395
Erythematous skin lesions occurred in rabbits 2 days after being fed upon by larvae or nymphs of the tick, Ixodes dammini. Similar lesions occurred in guinea pigs 7 days after a primary infestation with either larvae or nymphs. Host resistance to secondary feeding by larvae was demonstrated in guinea pigs and rabbits. Host resistance to secondary feeding by nymphs was seen in guinea pigs, but not in rabbits. Guinea pigs developed resistance to nymphs after being previously fed upon twice by larvae. All skin lesions in resistant guinea pigs contained large accumulations of basophils (49–76% of cells) with smaller (20–33%), but significant, numbers of eosinophils. These responses were characteristic of strong cutaneous basophil hypersensitivity reactions. Primary and secondary lesions in rabbits fed upon by larvae contained mostly mononuclear cells (46–52%) and moderate numbers (16–30%) of basophils and eosinophils. Primary and secondary lesions in rabbits fed upon by nymphs had few (3–11%) basophils and eosinophils and were dominated by mononuclear cells (73–86%). Thus, acquired resistance in guinea pigs and rabbits was associated with cutaneous basophil and eosinophil responses and the lack of resistance of rabbits to nymphs was associated with erythematous lesions dominated by mononuclear cells. The mononuclear nature of rabbit lesions induced by nymphal feeding was similar to that seen in erythema chronicum migrans in Lyme arthritis patients who are thought to have been fed upon by I. dammini nymphs. This study confirms the cutaneous basophil hypersensitivity characteristics of lesions in guinea pigs resistant to ticks and demonstrates a relationship between the mononuclear cell response of rabbits to nymphal I. dammini and the cellular response seen in patients with erythema chronicum migrans and Lyme arthritis. 相似文献
53.
Adenosine Transport into Guinea-pig Synaptosomes 总被引:17,自引:15,他引:2
Abstract: Kinetics for transport of adenosine into guinea-pig neocortex synaptosomes were studied by incubating them with [14 C]adenosine for up to 30 s. The apparent K m value of the high-affinity transport system for adenosine was 21.1 μM and the V max value was 257.3 pmol/min/mg protein. The transport system was inhibited by both compounds structurally related (compounds 554 and 555) and unrelated (dipyridamole) to adenosine. Because electrically stimulated synaptosomes release up to 1.5% of the adenosine derivative content per min, the physiological significance of adenosine uptake is discussed as a possible mechanism to compensate for the loss of adenine nucleotides from synaptosomes preparations. 相似文献
54.
Summary Following the injection of horseradish peroxidase into the pineal organ of the guinea pig, approximately 30 nerve fibers were demonstrated in the pineal stalk due to the retrograde transport of the tracer enzyme in these elements. Finely branched extensions of these nerve fibers are directed toward the distal portion of the pineal organ. This projection of central nervous elements enters the pineal organ via the habenular or posterior commissures. Neuronal perikarya projecting into the pineal organ are found in the region of the paraventricular nucleus near the border of the third ventricle.In partial fulfillment of the requirements for the degree of Dr. med., Faculty of Medicine, Justus Liebig University of Giessen 相似文献
55.
Cs. Léránth T. H. Williams M.D. Ph.D. D.Sc. J. Y. Jew A. Arimura 《Cell and tissue research》1980,212(1):83-89
Summary The superior cervical ganglia (SCG), celiac superior mesenteric ganglia (CMG), and splanchnic nerve of unoperated guinea pigs, as well as both proximal and distal stumps of a previously transected branch of the postganglionic plexus of the CMG, were immunostained for somatostatin (SS). In addition, the PAP technique was adapted for fine-structural visualization of SS. A greater proportion of cells were labeled for SS in the CMG than in the SCG. PAP molecules were present in one type of intraganglionic axons. Only two labeled axons were found in the splanchnic nerve. Neither proximal nor the distal stump of the transected CMG postganglionic nerve contained labeled axons. The present results support the hypothesis that the intraganglionic axons labeled for SS arise from SS-containing intraganglionic neurons. 相似文献
56.
Showdomycin inhibited pig brain ( with pseudo first-order kinetics. The rate of inhibition by showdomycin was examined in the presence of 16 combinations of four ligands, i.e., Na+, K+, Mg2+ and ATP, and was found to depend on the ligands added. Combinations of ligands were divided into five groups in terms of the magnitude of the rate constant; in the order of decreasing rate constants these were: (1), (2) , , and none, (3) , and , (4) and , , , and ATP. The highest rate was obtained in the presence of Na+, Mg2+ and ATP. The apparent concentrations of Na+, Mg2+ and ATP for half-maximum stimulation of inhibition () were 3 mM, 0.13 mM and 4μM, respectively. The rate was unchanged upon further increase in Na+ concentration from 140 to 1000 mM. The rates of inhibition could be explained on the basis of the enzyme forms present, including E1, E2, ES, E1-P and E2-P, i.e., E2 has higher reactivity with showdomycin than E1, while E2-P has almost the same reactivity as E1-P. We conclude that the reaction of ( proceeds via at least four kinds of enzyme form (E1, E2, E1 · nucleotide and EP), which all have different conformations. 相似文献
57.
Angelo F. Borghetti Mariarosaria Tramacere Paolo Ghiringhelli Alberto Severini John E. Kay 《生物化学与生物物理学报:生物膜》1981,646(2):218-230
Changes in neutral amino acid transport activity caused by addition of phytohaemagglutinin-P to quiescent peripheral pig lymphocytes have been evaluated by measurements of 14C-labelled neutral and analogue amino acids under conditions approaching initial entry rates. Utilizing methylaminoisobutyric acid, the best model substrate of System A, we confirmed our previous report (Borghetti, A.F., Kay, J.E. and Wheeler, K.P. (1979) Biochem. J. 182, 27–32) on the absence of this transport system in quiescent cells and its emergence following stimulation. Furthermore, we demonstrated the presence in quiescent cells of an Na+-dependent transport system for neutral amino acids that has been characterized as System ASC by several criteria including intolerance to methylaminoisobutyric acid, strict Na+-dependence, the property of transtimulation and specificity for pertinent substrates such as alanine, serine, cysteine and threonine. Analysis of the relationship between influx and substrate concentration revealed that two independent saturable components contribute to entry of alanine in quiescent cells: a low affinity () and a high affinity () component. The high affinity component could be inhibited in a competitive way by serine, cysteine and threonine, but methylaminoisobutyric acid did not change appreciably its constants. The enhanced activity of alanine transport through the ASC system observed in activated cells resulted from a large increase in the capacity () of the high affinity component without any substantial change in the apparent affinity constant (). 相似文献
58.
Experimental transfer of the lung stage worms of Angiostrongylus cantonensis was performed between permissive hosts (rats) and between permissive (rat) and nonpermissive hosts (guinea pigs and rabbits). These worms from rats were rejected when implanted into nonpermissive hosts. Unexpectedly, similar worms did not survive well even in permissive hosts; the majority of recipient rats did not have first-stage larvae (L1) in their stools and, even when positive for L1, the number of the larvae shed was few. These findings contrast with the successful pulmonary arterial transfer of younger, intracranial-stage worms. It was shown that differences in rat strain between donor and recipient had no significant effect on the subsequent worm survival in recipient hosts. The alteration of maintaining conditions of the intrapulmonary worms, prior to transfer, in terms of temperature, media, and maintaining period, also showed no profound effect on the subsequent worm survival. The kinetics of precipitating and reaginic antibody levels in rats implanted with the intrapulmonary worms were analogous to those in rats with intracranial-stage worms. The findings indicate that some qualitative differences may exist between the worms obtained from two different sites. 相似文献
59.
Anisakis simplex and Anisakis physeteris: physicochemical properties of larval and adult hemoglobins
To resolve the taxonomic relationship between two types of parasitic nematode larvae (Type I and II) and two species of parasitic nematode adults (Anisakis simplex and A. physeteris) of the aquatic ascarid genus Anisakis, collected in Japanese coastal water, a comparison was made of their hemoglobins' physicochemical properties. The larval hemoglobins were more similar to each other in electrophoretic pattern than to either adult, indeed there were few similarities whatsoever in these patterns of larval and adult hemoglobins. However, isoelectric points were 6.2 for the Type I larva and for A. simplex and 5.4 for the Type II larva and for A. physeteris. All samples showed identical patterns in spectrophotometric scanning. The circular dichroic spectra of the samples were also virtually identical, although slight differences were noted in the oxygenated hemoglobins; the Type II larva and A. physeteris exhibited a small positive peak at 575 nm but the Type I larva and A. simplex exhibited a much smaller peak (negative position). The sedimentation coefficients of the samples possessed essentially identical values (11.2–12.4). The molecular weights of the samples were estimated, roughly, to be in the range 33 to 43 × 104 by thin-layer chromatography on Sephadex G-200. The evidence suggests that a relationship may exist between the Type I larva and A. simplex, and between the Type II larva and A. physeteris. 相似文献
60.
The urinary excretion of 3-methylhistidine (3-MH) was used as an index of muscle protein catabolism in primary and secondary infections of the guinea pig with Trichostrongylus colubriformis and in uninfected animals fed quantitatively reduced rations. Catabolism, which was depressed in all three groups, was directly related to a fall in food consumption. Possible explanations for the greater depression of catabolism in the primary infection than in the uninfected guinea pigs and its fall in the secondary infection in spite of little change in consumption are briefly discussed. It was concluded that the faster rate of whole-body protein turnover reported earlier in this series on protein metabolism in intestinal nematode infection was not partly due to a faster rate of muscle protein catabolism. It was shown that the urinary excretion of 3-MH could be validly expressed in terms of unit creatinine. 相似文献