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1.
Zusammenfassung Im zweiten Abdominalganglion der Indischen Stabheuschrecke (Carausius morosus Br.) wurden 600 ± 50 Neurone, 1000 ± 100 Gliazellen und 500 ± 30 Perineuriumzellen, zusammen etwa 2100 Zellen gezählt. Die Volumina des Ganglions, des Neuropilems und des Zellcortex betrugen etwa: 140 · 10–4 mm3, 75 · 10–4 mm3 und 65 · 10–4 mm3.  相似文献   

2.
Zusammenfassung Erstmalig wurde radiochemisch reines59Fe (> 99,9999%) eingesetztg, um die radioaktive Halbwertzeit des59Fe mit 44,52±0,016 (¯m a ±SE) Tagen entsprechend einer Umwandlungskonstanten=0.015568±0.000 0056 [d–1] zu bestimmen. Radiochemisch reines59Fe wird im menschlichen Körper bei Männern mit einer Umsatzrate von 0,032%/Tag (=1,2 mg Fe/Tag) und bei menstruierenden Frauen mit 0,052%/Tag (=1,4 mg Fe/Tag) ausgeschieden. Diese Gesamtkörper-59Fe-Eliminationsrate entspricht dem Eisenbedarf des Menschen.  相似文献   

3.
Zusammenfassung Zur biologischen Dosimetrie wird eine Analyse für die Dizentiks-Ausbeute in Lymphozyten bei in vitro Bestrahlung aus peripherem Menschenblut mit 50-MeV-Protonen durchgeführt. Zur Approximation der experimentellen Befunde erweist sich eine Regressionskurve, entsprechend der GleichungY=(12,6±1,6)×10–5×D (1,36±0.027) als vorteilhaft.  相似文献   

4.
Summary The synthesis and testing of [N5-dimethyl-Gln6]-SP5–11 showed 37±12% contractile activity relative to SP, and intrinsic efficacy 98±4%. This finding indicates that the carboxamide groups of the dual Gln5-Gln6 moiety are not equally related with the contractile response of the C-terminal heptapeptide of SP.The authors wish to express their deep appreciation to Professor H. Niedrich and Dr J. Bergmann of the Institute of Drug Research, Academy of Sciences of DDR, Berlin, for their valuable help in providing the biological data.  相似文献   

5.
Summary Release of endogenous somatostatin (SRIF) from the rat cerebral cortical slices incubated in Krebs-bicarbonate buffer was increased from the basal rate of 3.4±0.6% of the total SRIF content in 15 min at [K+]o=5.6 mM, to 13.1±1.6% upon raising the [K+]o to 56.6 mM. The high-K+ evoked SRIF release was absent when Ca++ in the medium was replaced by Mn++. The isolated synaptosomes from rat cerebral cortex contain 13.2±3.1 ng SRIF/mg protein compared to 0.33±0.01 ng/mg protein in the cortical tissue as a whole, suggesting that nerve terminals are the main source of the peptide released upon membrane depolarization.The study was supported by a grant from the Medical Research Council of Canada. Results of this work have been published in part as abstracts: Can. Physiol.9, 45 (1978), and Fedn Proc.37, 665 (1978).The authors are greatly indebted to Dr M. Gotz and the Ayerst Research Laboratories for the most generous supply of the synthetic somatostatin.  相似文献   

6.
Radioimmunoassay was used to determine levels of the stress-inducible glucocorticoid, cortisol, circulating in the plasma of the extremely stenothermal Antarctic fishPagothenia borchgrevinki at rest and after heat stress. Fish sampled immediately after capture (–1.9°C) had low cortisol levels (10.4±1.4 ng ml–1, mean±SEM) as did fish which were laboratory rested for 3 days. Sudden exposure to 5°C (48h) resulted in a peak cortisol value after 3 h (69.9±6.8 ng ml–1) whereas exposure to 8°C (6h) resulted in a peak value after 1 h (73.5±8.0 ng ml–1). At both temperatures levels remained significantly elevated (p<0.05) for the entire period of exposure. Increased temperature also resulted in a significant change in haemoglobin, haematocrit and mean cell haemoglobin concentration (MCHC) (p<0.05). Plasma lactate was significantly elevated only after exposure to 8°C (p<0.05). Plasma cortisol levels fromP. borchgrevinki are reported here for the first time and show this cryopelagic Antarctic species to have an unusual hormonal stress profile.  相似文献   

7.
Calorimetric experiments were performed on yeast extracts in which glycolytic oscillations were occurring. High metabolic fluxes coincided with low amplitudes and with high frequencies in a temperature range from 283 to 303 K, yielding an activation energy ofE a=76.8 kJ mol–1 and a mean Q10 value of 2.5±0.4. The calorimetrically determined reaction enthalpy fH0, of the glycolytic catabolism of glucose revealed two distinct groups of extract preparations, with no intermediate values. The values were –107.5±28.7 kJ mol–1 and –30.8±5.7 kJmol–1, respectively, while –100.0 kJ mol–1 was predicted from theoretical calculations. Kreuzberg and Betz6 predicted rate limiting effects of GAPDH in oscillating extracts. However, when possible effects of GAPDH on frequency, number of oscillations or total heat production were examined, no influence of increasing or reducing the initial GAPDH concentration could be found. The results are discussed with reference to existing models of glycolytic oscillations.  相似文献   

8.
Summary The red-brown haemovanadin which is contained in the haemolysate (Henze Solution) of blood cells of the ascidiaPhallusia mamillata Cuvier is a chromoproteid with trivalent vanadium as the central atom and sulphuric acid bound coordinatively. It is found to have a molecular weight of 24,400±1,900 according to the estimation of the diffusion coefficient (D=6.87±0.2 · 10–7 cm2 · s–1 at pH 2.5–2.8).

Dem Entdecker des Hämovanadins zum 80. Geburtstag gewidmet.  相似文献   

9.
Zusammenfassung Es wird über die Totalsynthese von verschiedenen Derivaten des (±)-6-Oxa- und Aza-Östrons und die Umwandlung von (±)-17-Oxy-3-methoxy-6-oxa-östratrien-1, 3, 510 zu Verbindungen der (±)-19-Nor-6-oxa-testosteron-Klasse berichtet. Die biologische Wirksamkeit der Glieder in der 6-Oxa-Reihe wird beschrieben.  相似文献   

10.
Summary Electron microscopy of the partially heat denatured ribosomal DNA (rDNA) from sea urchin (Lytechinus variegatus) sperm has demonstrated that it consists of repeating units of 3.6±0.2 m, corresponding to a mol.wt of 7.2±0.4×106. Based on differential denaturability, each repeat unit is divided into 2 regions. The larger region of 2.47±0.11 m (mol.wt 4.9±0.22×106) corresponds in length to the ribosomal precursor RNA of sea urchins and the smaller, GC-rich, subunit of 1.16±0.09 m (mol.wt 2.3±0.18×106) is presumed to contain non-transcribed spacer sequences.Acknowledgments. This paper is dedicated to the memory of Dr D. P. Costello whose insprration made this work possible. I gratefully acknowledge the valuable advice of Drs D.W. Stafford and M.A. Bleyman.  相似文献   

11.
Summary Two closely related forms ofCoregonus from Lake Neuchatel were examined cytologically and biochemically, in order to ascertain the chromosome number and the DNA content of haploid and diploid nuclei.Coregonus fera has 2N=78 ± 2 chromosomes, and a DNA content (diploid) of 5.8 × 10−9 mg;Coregonus macrophthalmus, 2N=78+ ± 3, DNA content of 6.1 × 10−9 mg. The difference between the two DNA constants is statistically significant. These results do not support the hypothesis which postulates that polyploidy may be a determining factor in the speciation of these fishes.   相似文献   

12.
Summary Pure porcine VIP was infused systemically in 4 conscious dogs and systemically and intraportally in 6 anesthetized pigs. At 2.3 pmoles·kg–1·min–1 the MCR was 10.7±1.0 ml·kg–1·min–1 in dog and 7.6±1.5 (systemic) and 16.5±2.0 (portal) in pig. The t 1/2's were 1.0±0.12 and 1.0±0.05 respectively. These values agree with those observed in man. This very high single pass tissue clearance does not suggest a hormonal role for VIP.  相似文献   

13.
Summary The space-group of Cu(NH3)4SO4·H2O isD 2h 16 orD 2h 13 (D 2h 5 , D 2h 1 ) with a=7,07, b=12,12, c=10,66 Å ± 1%.  相似文献   

14.
Summary Splanchnic and systemic hemodynamic studies were performed in a rat model of parabiosis and portal hypertension. A portal hypertensive and a normal rat were surgically united side to side. A hyperdynamic circulation, characterized by increased cardiac index (413±26 vs 318±23 ml·min–1·kg–1; p<0.05) and portal venous inflow (9.61±1.29 vs 6.33±0.36 ml·min–1·100 g b.wt–1; p<0.05), was found in all the portal hypertensive rats but not in the normal parabiotic partners. These results do not support the existence of a transferable humoral factor mediating the hyperdynamic circulatory state of chronic portal hypertension.Acknowledgment. The authors express their appreciation to Martha Shea for technical assistance.  相似文献   

15.
Myeloperoxidase (MPO) is an enzyme located within polymorphonuclear neutrophils capable of producting cytotoxic oxidant species that are particularly active against bacteria with polysaccharide capsules.Pseudomonas aeruginosa (106 bacteria per 1 ml) are killed within 1 h in vitro by a MPO/H2O2/Cl system (48 mU=132 ng of MPO). The question arose as to whether human macrophages would acquire cytotoxic activity when loaded with this enzyme. Monocytes were therefore isolated from human blood and cultured for up to ten days to induce maturation to macrophages. These cells lost endogenous MPO within five days while H2O2 production in response to stimulation by phorbol myristate acetate (10–6M) decreased to 23% within ten days. On the other hand, their capacity to take up exogenous MPO increased fourfold from day three to day ten. Human macrophages cultured from eight days (when both H2O2 production and MPO uptake were sufficient) were therefore used to study the effects of MPO uptake on cytocidal activity againstPseudomonas aeruginosa. After a 1 h MPO loading period, macrophages (5×105 cells per ml) were incubated in the presence of bacteria (0.5 to 2×106 bacteria per ml) for 2 h at 37°C. At a bacteria/macrophage ratio of 1, only 34.8±7.0% of bacteria survived (compared to killing by non-loaded macrophages), while 74.4±9.3% survived at a ratio of 4. From these results, we conclude that loading macrophages with exogenous MPO could enhance their microbicidal activity, suggesting a potentially useful therapeutic application.  相似文献   

16.
Summary The structures of 2 new polyhydroxylated cannabinoids, (±)9, 10-dihydroxy- 6a(10a)-tetrahydorcannabinol and (±)8, 9-dihydroxy- 6a(10a)-tetrahydrocannabinol, obtained from a hexane extract of an IndianCannabis variant were determined by spectral means and correlation with cannabinol.Acknowledgments. Supported by contract No. HSM-42-70-109 from the National Institute on Drug Abuse and the Research Institute of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi. The authors are grateful to Mrs Glenda Lewis (Research Institute) for running the gas chromatographic analyses and to Mr C. Versluis (Analytical Chemistry Laboratory, University Of Utrecht, The Netherlands) for recording an element list of both compounds.Cannabis Herbarium specimens are stored in the herbarium, Department of Pharmacology, School of Pharmacy, University of Mississippi, University, MS 38677, USA.  相似文献   

17.
Summary 5,5-Diphenylglycocyamidines bearing an alkyl group in position 3 are partly rearranged to the corresponding N2-alkyl derivatives on heating with alcoholic ammonia in the presence of ammonium acetate. Prolonged heating with ammonium acetate leads to N-dealkylation both of N3- and N2-alkyl derivatives. 5,5-Diphenylglycocyamidine in turn is mono- or dialkylated at N2 on heating with the acetates of primary and secondary amines respectively. A mechanism for these reactions is proposed.

Mitteilung über Hydantoine, Thiohydantoine und Glykocyamidine.

Mitteilung:K. Lempert, Magyar Tudományos Akadémia Kémiai Tudományok Osztályának Közleményei [Ber. Ung. Akad. Wiss., Kl. Chem. Wiss.]12, 59 (1959). — Chem. Reviews59, 667 (1959).  相似文献   

18.
Summary A fine quantitative evaluation of ferritin aggregates in rat GBM permits to counts 5.08±1.51 and 18.30±3.21 g/cm2, respectively 30 and 60 min after ferritin injection; likewise, 30 min after ferritin administration, 5.08±1.51 and 17.11±3.9 g/cm2, respectively in normal and theophylline-treated animals.  相似文献   

19.
Human umbilical vein endothelial cells (HUVECs) in primary cultures were perfused under normoxic or hypoxic conditions. These cells were stimulated twice for 3 min by increased flow (from 0.5 to 3.0 ml/min). Under hypoxic conditions the basal release of ATP was the same as under normoxic conditions, but during increased flow the release was greater (0.58±0.07>0.32±0.04 pmoles/ml/106 cells (+78%), for the first period of stimulation; 0.39±0.05>0.22±0.03 pmoles/ml/106 cells (+79%) for the second period). Further experiments with sequential increments in flow rate showed that under both normoxic and hypoxic conditions, a positive correlation existed between ATP release and the rate of flow but there was always more ATP released under hypoxic conditions regardless of the flow rate.HUVECs in secondary culture (second passage) were similarly stimulated. No differences were observed between normoxic and hypoxic conditions. In both cases, the quantity of ATP released during high flow (0.050±0.004 pmoles/ml/106 cells) was significantly smaller than the quantity of ATP released during low flow (0.09±0.01 pmoles/ml/106 cells).To conclude, since hypoxia alone did not affect ATP release, there appears to be a synergistic relationship between increased shear stress and hypoxia in the stimulation of ATP release from HUVECs. Moreover, the release of ATP under these conditions seems to be a property of highly differentiated endothelial cells.  相似文献   

20.
    
Summary Eglestonite has been investigated by powder and rotation photographs;a=8,02±0,02 Å,Z=3; the space-group is O h 9 . The Hg-atoms form Hg2-groups as in Hg2Cl2, and therefore the formula must be written Hg4Cl2O. It was not yet possible to find the positions of Cl and O, because their scattering-power is too low.  相似文献   

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