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1.
Summary Application of lead suppressed the delayed type hypersensitivity (DTH) of mice induced by sheep red blood cells (SRBC). Inhibition of elicitation of DTH in primary as well as in secondary response was correlated with the concentration of lead in the blood of the mice.Acknowledgments. Supported by the Georg-und-Agnes-Blumenthal-Stiftung and the Verein für Wasser-, Boden- und Lufthygiene. We thank Miss Schachtschneider for the excellent technical assistance.  相似文献   

2.
Summary In the host-symbiont-cycle ofEuscelis plebejus and its bacterial symbionts each of both symbionts (a and t) appears in an infection form during the intraovarial transmission (adult female) as well as during the entrance into the mycetocytes (embryo) and in a vegetative form during the remaining time of the cycle.This work was supported in part by a grant from the Deutsche Forschungsgemeinschaft to ProfessorK. Sander, whom I thank for helpful discussions.  相似文献   

3.
Summary The miracle of caryokinesis was the starting point that stimulated Alexander G. Gurwitsch to carry out his famous mitogenetic experiments in 1923. The results obtained confirmed his hypothesis of a weak radiation from cells, which is able to trigger the growth of other cells. Extensive experimental work within the first two decades after this discovery indicated that the problem of mitogenetic radiations is generally related to the biological significance of UV-radiation. Both energetic and informational aspects have to be considered, namely radiation effective in activating molecules, and that involved in arranging them into larger units.The molecular organization of biological structures is evidently governed by nonequilibrium conditions needing the uptake or emission of radiation. These concepts of A. G. Gurwitsch can be linked with modern approaches based on hypotheses of coherence in biology, synergetics and dissipative structures. However, the question of causal interrelationships between this part of non-equilibrium radiation and biological matter on different levels of evolution has to be solved now.  相似文献   

4.
    
Summary Critical concentration of unbound cadmium in the rabbit renal cortex was around 13 g Cd/g, which was far lower than the critical concentration of total cadmium in the renal cortex, 200–300 g Cd/g, and a little lower than the critical concentration of non-MT-Cd in the renal cortex, 35–60 g Cd/g, respectively. The above result may suggest that it is necessary to identify the chemical form of active cadmium in the renal cortex.  相似文献   

5.
Summary The effects of pollution at population level are considered in relation to demographic characteristics and overall to the birthrate. The direct and indirect effects of pollution on community structure is discussed. The influence of pollution may vary according to the food-chain structure; (as a consequence, the hazard ceteris paribus will be greater in freshwater communities than in marine ones). Relations between diversity and stability are discussed. In addition, the advantages and difficulties in using diversity and biotic indices for monitoring polluted water are taken into account.  相似文献   

6.
Summary Based on the literature and the author's own research on general and comparative heart physiology, the term of Automaty-Potentiality is discussed and differentiated. Adouble term Automaty-Dominance/Automaty-Latence is proposed as serviceable.  相似文献   

7.
Summary In the oocytes ofAplysia depilans it has been observed electronmicroscopically that gemmae or daughter-nucleoli separate from the nucleolus. These gemmae after having overcome the nuclear membrane, would aggregate together, even after transformation, into yolk globules. These observations seem to give plausibility to the hypothesis that there is a close relationship between production of ribonucleoproteic material by the nucleolus and yolk production.  相似文献   

8.
Our object in this paper is to study the antecedents, contents, implications, and impact of a not well-known or appreciated paper by EHRENFEST in 1911 on the essential nature of the different quantum hypotheses in radiation theory. After a careful analysis of EHRENFESTs notebooks, correspondence, and publications, we conclude that the essential points of EHRENFESTs paper were not perceived to a large extent, and hence that its implications were not considered thoroughly. Specifically, we show that EHRENFEST contributed significantly to the clarifications of the differences between PLANCKs and EINSTEINs respective quantum hypotheses, as well as to those of the concepts discontinuity, quantization, and corpuscularity.  相似文献   

9.
Summary Kinetics studies of haemolymph -glucosidase inhibition by D. glucose led to general correlations between inhibition and control parameters, all over the honeybee development. Maximum velocities are not affected by the inhibition, while affinity constants are always significantly increased, and Hill coefficients tend to decrease, especially in foraging adults and in prenymphs. In this later case, the n-type effect tends to break the manifestation of the K-type mechanism.  相似文献   

10.
Summary In inbred mice possessing high and low tissue superoxide dismutase (SOD) activity, it was observed that the difference in the SOD activities of the liver homogenates during development attains the maximum characteristic of the strain by about the 150th day. Subsequently, the SOD activity change displays a tendency in contrast with the age and the basic state. In the course of the development, a difference was also observed between the 2 mouse strains in the lipid peroxidation variation.Part XVIII of the series Properties of enzymes.  相似文献   

11.
Summary The vast majority of oil-droplets in the dark and light-adapted retinal twin-cones ofPoecilia reticulata is of the matrix-type. In bright light (day light+overhead strip light) there occurs in some regions a very pronounced numerical change from matrix to cristate-type, whereas other regions remain unaffected. The functional significance of these differences is discussed.  相似文献   

12.
Summary Glycogen substance, detected by the PAS-reaction in the so-called Ringbinden of the trunk musculature from the larval form ofAmblystoma mexicanum Cope, is described. The PAS-glycogen reaction in the myofibril complex of the common Ringbinde does not differ from that found in the normal one.  相似文献   

13.
14.
Summary The amino acid sequence was compared among the three allelic variants (allozymes) ofsn-glycerol-3-phosphate dehydrogenase inD. virilis, which are detected by one-dimensional electrophoresis. The GPDHf variant was different from the GPDHm by only one substitution of 68-lysine for asparagine; GPDHs differed from GPDHm by substitution of 127-glycine for arginine. No electrophoretically silent substitutions were found in a total of 352 amino acid residues.  相似文献   

15.
Summary The chemical composition of liver plasma membrane was studied in Wistar rats aged between 3 and 24 months. Results obtained indicate a significant age-dependent positive correlation of both the protein:phospholipid and cholesterol:phospholipid ratios, whereas the protein:cholesterol ratio seems to remain unaffected. Phospholipid analysis of liver plasma membrane reveals that only the phosphatidylcholine content has a significant negative correlation with age; all other phospholipid species remain basically unchanged.Supported by a grant of the Italian National Research Council, Project Preventive and Rehabilitative Medicine, Subproject Mechanisms of Aging.  相似文献   

16.
Summary The antigens and soluble proteins ofNeurospora crassa wild-type and its conidiation deficient mutant amyc were analyzed by immunoelectrophoresis and acrylamide gel electrophoresis respectively. Comparison of the patterns of the soluble proteins of the 2 strains, obtained with both techniques, showed an alteration of antigens and proteins in the mutant. A specific antigenic protein present in the wild-type, presumably in connection with conidiation, was also found in the mutant amyc when it was induced to form conidia.  相似文献   

17.
Zusammenfassung Die cancerostatischen Viscum-Proteine induzieren im Tierversuch mit geringsten Dosen eine Proliferation des Thymus und verhindern prophylaktisch das Angehen von Tumoren. Höhere Dosen zerstören dagegen den Immunapparat durch Überbeanspruchung und die Tumorhemmung bleibt aus.

We are indebted to the Deutsche Forschungsgemeinschaft for financial support (M. St.) and for granting a Forschungsfreijahr (F. V.).  相似文献   

18.
Summary Methomyl, or S-methyl-N [(methylcarbamoyl)oxy] thioacetimidate, a common insecticide, has been found to be a specific poison of mitochondria of corn with Texas cytoplasm. Its hydrolysis under very mild acidic conditions affords thiomethyl methylthiosulphonate, which strongly inhibits the activity of CmST and N mitochondria of corn.  相似文献   

19.
Summary Apart from cancer and mutation induction, radiobiological effects on mammals are mostly attributable to cell death, defined as loss of proliferative capacity. Survival curves relate retention of that capacity to radiation dose, and often manifest a quasi-threshold (shoulder). The shoulder is attributable to an initial mechanism of repair (Q-repair) which is gradually depleted as dose increases. Another form of repair, which is not depleted (P-repair), increases the dose required to deliver an average of one lethal event per cell (dose D0). Neither form of repair can unambiguously be linked with repair of defects in isolated DNA. An important initial lesion may well be disruption of the complex structural relationship between the DNA, nuclear membrane and associated proteins. One form of P-repair may be restoration of that structural relationship.  相似文献   

20.
Summary Axillary 5-androst-16-en-3-one (5-androstenone) levels were found to be significantly higher in men than in women but do not vary between left and right axillae, are not related to age, handedness or degree of hirsutism (in women) nor to anosmia to this steroid. In men (but not in women), levels are related linearly to axillary cholesterol concentrations but not to squalene. Olfactory thresholds for 5-androstenone varied widely, the lowest recorded being 0.2 ppb, but there was no difference in thresholds between men and women. Women (70%) found the smell repellant but anosmia did not differ greatly between men and women (9–20%). Anosmia to the smell of 5-androst-16-en-3-ol was most marked in women (90%) rather than in men (45%). Axillary 5-androstenone values were generally consistent with the musky or strong smells of male axillary extracts, compared with the sweet smell of those from female subjects.Supported by the Herbert Dunhill Trust.  相似文献   

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