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1.
Summary Body temperatures and self-assessed mood scales were recorded for 7 weeks or more by male volunteers. Auto-correlations of temperatures from the 21 subjects show evidence of a significant peak at the 20-day-interval. The self-assessed measure of Alertness (from 18 of them) also shows some evidence of rhythmicity, at the 22-day-period.  相似文献   

2.
Riassunto Mediante esperimenti in vitro, è stato accertato che i primi stadi della biosintesi delle feomelanine conducono alla formazione di derivati diidrobenzotiazinici, ai quali sono state assegnate le strutture III e IV.

This investigation was supported by a grant from the Laboratorio di Chimica e Fisica per lo Studio delle Molecole di Interesse Biologico del C.N.R., Napoli.  相似文献   

3.
We noted the earliest morphological changes in the motor endplates 8 weeks after the induction of streptozotocin diabetes in rats. Morphometric measurements showed reduced axonal areas of the lateral plantar and the sciatic nerves in the diabetic rats 28 but not 2 and 8 weeks after the experiment. These findings suggested distal axonopathy.  相似文献   

4.
Summary We noted the earliest morphological changes in the motor endplates 8 weeks after the induction of streptozotocin diabetes in rats. Morphometric measurements showed reduced axonal areas of the lateral plantar and the sicatic nerves in the diabetic rats 28 but not 2 and 8 weeks after the experiment. These findings suggested distal axonopathy.  相似文献   

5.
Despite aspirations to substitute animal experimentation with alternative methods and recent progress in the area of non-animal approaches, such as organoïds and organ(s)-on-a-chip technologies, there is no extensive replacement of animal-based research in biomedicine. In this paper, I will analyse this state of affairs with reference to key institutional and socio-epistemic barriers for the development and use of non-animal approaches in the context of biomedical research in Europe. I will argue that there exist several factors that inhibit change in this context. In particular, there is what I call “scientific inertia”, i.e. a certain degree of conservatism in scientific practice regarding the development and use of non-animal approaches to replace animal experimentation. This type of inertia is facilitated by socio-epistemic characteristics of animal-based research in the life sciences and is a key factor in understanding the status quo in biomedical research. The underlying reasons for scientific inertia have not received sufficient attention in the literature to date because the phenomenon transcends traditional disciplinary boundaries in the study of animal experimentation. This paper addresses this issue and seeks to contribute to a better understanding of scientific inertia by using a methodology that looks at the interplay of institutional, epistemic, and regulatory aspects of animal-based research.  相似文献   

6.
Summary Angiogenic activity, tested on the chorioallantoid membrane of the chicken embryo, was present in the CSF of patients with meningioma and glioblastoma and in patients with other malignancies with no clinical signs of CNS involvement.  相似文献   

7.
Summary Stimulation of both vagi caused a significant rise in arterial plasma vasoactive intestinal peptide (VIP) concentration in 3–5-week-old calves with cut splanchnic nerves. This was associated with a pronounced rise in the VIP concentration of intestinal lymph showing that vagal stimulation causes release of VIP from splanchnic viscera.Acknowledgment. This work has been supported by grants from the Agricultural Research Council and the Medical Research Council and we are indebted to Dr D.M. Burley (CIBA) for his continued support.  相似文献   

8.
Summary It is reported that Ca2+-induced discharge of in situ nematocytes of acontia ofCalliactis parasitica can occur by cell-to-cell transmission along the acontial filament at a speed that averages 9.8·10–3 cm–1. The discharge is preceded by protrusion of nematocytes that proceeds along the acontium at a slightly higher speed.  相似文献   

9.
Summary Formation of DNA proviruses of RNA viruses, Sendai and Newcastle disease, was studied. DNA provirus of NDV was shown to be formed in mouse L-cells and Sendai DNA provirus in Ehrlich ascites carcinoma cells within 2–3 days post infection.  相似文献   

10.
城市化是经济社会发展的必然选择。然而,随着中国城市化飞速发展,也产生了城市水、大气、固体废弃物和噪声污染等一系列生态环境问题。同时,随着环境意识的增强,人们对居住环境质量的要求不断提高,致使城市化过程中环境抗争事件不断涌现。本文回顾了已有研究文献,以国外环境抗争、国内农村环境抗争与城市环境抗争作对比,突出城市环境抗争的特点;从抗争的情感基础、精英力量、弱组织化和互动过程四个方面对城市的环境抗争进行建构;从抗争力量、制度化因素、发展观念和社会力量四个方面分析当前环境抗争所面临的一系列困境。培育公民社会、更新地方政府的发展观念、加强社会科学与自然科学和管理科学之间的交叉研究等是应对当前困境最根本的出路。  相似文献   

11.
Summary Insertion of iron nail into the vitreous cavity provoked the formation of lipoperoxide in the retina. In accord with the increase in lipoperoxide in the retina, ERG began to decrease. In vitro experiment using isolated retina, lipoperoxide was found to be increased in the presence of ferric or ferrous ions, while it was inhibited by adding antioxidants or ethylenediamine tetraacetate. From these results, direct cause of retinal degeneration in siderosis could be ascribed to the formation of lipoperoxide by iron-ions liberated from the piece of iron, resulting into the degeneration of the visual cell layers of the retina.  相似文献   

12.
13.
New intermediates in phaemelanogenesis in vitro   总被引:1,自引:0,他引:1  
  相似文献   

14.
15.
The changes in serum testosterone and dihydrotestosterone concentrations have been measured in the newborn Rat, before, during and up to 6 hrs after birth. A sudden and transient increase of serum testosterone has been found between 0 and 2 hrs. At 4 hrs, the value returns to that found in the foetus at the end of gestation.  相似文献   

16.
Résumé Les sportifs examinés au repos, après plusieurs jours consécutifs d'entraînement ou de compétitions ont un niveau nettement plus élevé que le groupe de contrôle pour l'1-antitrypsine, l'2-HS-glycoprotéine, l'2-macroglobuline, la transferrine, la céruloplasmine et le cuivre sériques. La signification biologique possible de ces faits est discutée.

With support from the Deutsche Forschungsgemeinschaft and Kuratorium für Sportmedizin.

Dozenten-Stipendiat der Alexander-von-Humboldt-Stiftung.  相似文献   

17.
Rat serum at different concentrations added to cultured Rat heart cells medium increased spontaneous beating frequency of myoblasts. This increase occurred instantaneously and lasted more than 24 hrs. It was related to the serum concentration used. Electrophysiological recording showed a decrease in the iso-electric phase duration of membrane potential, with no change in action potential. In spite of the beating frequency increase, cells remained sensitive to the chronotrope positive action induced by Isoprenaline. There was no difference between male and female sera. The global results could partly be explained by the action of Ca++ in Rat serum.  相似文献   

18.
Zusammenfassung Blattmaterial vonAtropa belladonna vermag unter geeigneten Bedingungen ganze Pflanzen zu regenerieren. Ausgangspunkt der Knospenbildung ist das Pallisadenparenchym.

Acknowledgements: I wish to thank the head of the Department of General Botany Prof.A. Szweykowska for the facilities and critical reading of this report.  相似文献   

19.
Every tenth person in Central Europe is a pollinosis patient. The time of ripening and release of pollen, as well as pollen flight, all depend on the weather. Because each year is different from every other, mean values from pollen calendars do not provide any practical help for allergy-sufferers. For this reason, in many European countries, measuring networks have been established during the last 10 years as a basis for forecasting the prevalence of airborne pollen for the following 2–3 days, in connection with the weather forecast. Cooperation and communication also exist on a European level, and a European Pollen Database has been established.  相似文献   

20.
Catabolism of juvenile hormone was studied in vivo in the African locust by injection of the labelled natural enantiomer (10R) (12-3H) JH-III. Due to the poor solubility of JH in aqueous solution, it was injected in a water-miscible solvent. Ethanol was chosen for its apparently low toxicity towards the locust. In these experimental conditions, reverse phase liquid chromatography procedure (RP-HPLC) coupled with on line radiodetection, revealed an apolar metabolite of JH-III. This compound was found both in adult females and in fifth stadium larvae. We demonstrate that this metabolite resulted from substitution of the carboxyl methyl group of JH-III by some hydrophobic moiety. This compound co-migrates in our RP-HPLC system with the JH analog epoxy-ethyl farnesoate (JH-III ethyl ester) obtained by KCN-catalysed transesterification of JH-III in ethanol. Both JH-III ethyl ester of chemical origin and biological compounds extracted from locusts give the same spectra when analyzed by gas chromatography-mass spectroscopy (GC-MS). Transesterification of JH-III was not observed with locust tissues incubated in vitro but occurred in vivo even if JH was injected in other alcoholic solvents such as propanol. Our data suggest that transesterification of JH-III occurred in vivo and underline the role of injecting solvent in in vivo studies.  相似文献   

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