ISSN:0004-945X    

DOI:10.1038/icb.1966.1

出版商:Nature Publishing Group    

年代:1966

数据来源: WILEY

摘要:

SummarySine‐wave techniques have been used to analyse the “input characteristics” of toad skeletal muscle fibres to show that, unlike the frog, there is no measurable difference between the admittance of a small section of membrane and that of a parallel circuit containing one resistance and one capacitance. Falk and Fatt's (1964) three‐path model for the frog, containing a small series resistance with part of the capacitance, remains valid, but in the toad it is undistinguishable from a simple two‐path model. It is postulated that the site of the additional resistance is at the entrance of the tubular system, and the difference between frog and toad is ascribed to a difference of the membrane across the tubules at the sarcolemma. Since the method limits the maximum measuring frequency to about 1000 c/s, it is concluded that the small series resistance for the toad tubular‐system capacitance is less than 4 Ω cm.2, which is not measurable. The absence of the late after‐potential in toad muscle is explained on this basis.

ISSN:0004-945X    

DOI:10.1038/icb.1966.2

出版商:Nature Publishing Group    

年代:1966

数据来源: WILEY

摘要:

SummaryThe effect of local temperature an the transference of protein mid of the lipoproteins from plasma to lymph in the hind paw of hypercholesterolaemic rabbits has been studied before and after thermally injuring the paw by immersion in water at 60° for 1 min.The hind paws were kept either at 10° or 45°. In uninjured limbs the lymph flow was greater, but the concentrations of albumin, globulin, total cholesterol and phospholipid were less with the paw at 45° than at 10°.After injury to both paws, the lymph flow and also the concentrations of albumin and of the lipoproteins of densities 1·063–1·200, 1·019–1·063 and<1·019 g./ml. were greater with the paw at 45° than at 10°, but in each case molecular sieving of these macromolecules was evident, although at a different level. These results suggest that, after a thermal injury, the sieving mechanism of the skin capilliries can be varied by altering the capillary pressure.

ISSN:0004-945X    

DOI:10.1038/icb.1966.3

出版商:Nature Publishing Group    

年代:1966

数据来源: WILEY

摘要:

SummaryThe transfer of albumin, globulin and the lipopruteins of density 1·063–1·200, 1·019–1·063 and<1·019 across the capillaries of the hind paw of the hypercholcsterolaemic rabbit was determined by collecting and analysing the lymph draining from this region.These measurements were made in the uninjured paw and in thr paw after a thermal injury which varied in intensity in different groups of animals. This was achieved by immersing the paw in water for 1 min. at one of the following temperatures: 50°, 52·5°, 55°, 57·5°, 60° or 70°.The total transfer ol fluid, protein anil lipoprutein showed a graded response from normal with injuries of increasing intensity. The lymph: plasma ratios, however, suggested a sudden change after injury in the degree of molecular sieving. The results suggest that, if the basement membrane is the only sieving mechanism in the capillaries of both normal and injured tissue, its effectiveness decreases with injury.

ISSN:0004-945X    

DOI:10.1038/icb.1966.4

出版商:Nature Publishing Group    

年代:1966

数据来源: WILEY

摘要:

SummaryInfective ova of the ascaroid parasiteAmplicaecum robertsiwere shown to cause pronounced eosinophilia following injection into the stomach of rats. Eosinophila developed 7 days after injection of the eggs and reached maximum values at approximately 18 days after infection, when there was a 8‐fold increase above control values. The level of eosinophils in the blood gradually decreased from the maximum values, but significant eoinophilia was still present at 40 days. A significant decrease was found in the level of 11‐hydroxycorticoids in the plasma of Amplicaecum‐infected rats compared with normal animals. The rate of clearance of colloidal carbon from the bloodstream was found to be greater in Amplicaecum‐treated animals than in normal rats. No significant difference was demonstrated in plasma histamine levels in normal and Amplicaecuminfected animals following an injection of the histamine release agent, dextran.

ISSN:0004-945X    

DOI:10.1038/icb.1966.5

出版商:Nature Publishing Group    

年代:1966

数据来源: WILEY

摘要:

SummaryThe growth of epiphyseal cartilage of femur and tibia is stimulated by operative interference and insertion of a tube into the knee joint.

ISSN:0004-945X    

DOI:10.1038/icb.1966.6

出版商:Nature Publishing Group    

年代:1966

数据来源: WILEY

摘要:

SummaryRats with an opaque lens over one eye for 15 days have a depressed cholinesterase activity in that retina. Cholinesterase activity returns to normal 4 days after the opaque lens is removed. An opaque lens decreases the rate of return of cholinesterase activity after diisopropyl fluorophosphate administration. Variation in light stimulation does not significantly alter the rate of return of cholinesterase activity. Despite its pupil‐enlarging effect, continuous systemic administration of atropine depresses the rate of return of cholinesterase activity in the light‐stimulated eyes of diisopropyl fluorophosphate‐treated rats. In these animals atropine also depresses the ratio of cholinesterase content of the visual cortex to whole brain.

ISSN:0004-945X    

DOI:10.1038/icb.1966.7

出版商:Nature Publishing Group    

年代:1966

数据来源: WILEY

摘要:

SummaryThe activity of cholinesterase was measured in brain cortex, basal ganglia, hippocampus, thalamus, colliculi, cerebellum, medulla, hypothalamus, spinal cord, gastrornemius muscle, adrenal gland and retina at various times after treatment of rats with diisopropyl fluorophosphate alone or together with 1,3‐bis(4‐hydroxyiminomethylpyridinium) propane dibromide (C434)2. After injection of 1 mg. diisopropyl fluorophosphate/kg. body weight intramuscularly in the; leg the eholinesterase activity of neural tissue was decreased to 30–40% of control values and it increased to 70–100% of control values in 25 days. In each case the rate of increase of activity with time decreased throughout this period, and was not changed significantly by concurrent treatment with C434. The proportional rate of increase in the cerebellum was significantly greater than that in other neural tissue.The decrease in cholinesterasc activity of leg muscle injected with diisopropyl fluorophosphate was less marked in animals treated with C434. The activity in adrenals returned to control values within 5 days and was 100–120% of control values for 5–10 days; these effects were not altered by treatment with C434.Rats injected initially with 1·0 mg. and subsequently on every third day with 0·5 mg./kg. body weight of diisopropyl fluorophosphate, with or without C434, for periods up to 62 days showed no behavioural abnormalities or evidence of toxic effects, although the cholinesterase activity of regions of the brain was 20–40% of control values. In chronic treated animals C434 did not significantly alter muscle cholinesterase activity.

ISSN:0004-945X    

DOI:10.1038/icb.1966.8

出版商:Nature Publishing Group    

年代:1966

数据来源: WILEY

摘要:

SummaryDialysed and concentrated culture filtrates and purified exo‐antigen preparations of 21Dermatophilusstrains were tested against the exo‐antigen antisera by the diffusion‐precipitation and the immunoelectrophoresis tests. Chromatography showed that exo‐antigen complexes contained a hexosamine‐galactose‐xylose peptide. Four exo‐antigen groups of theDermatophiluswere distinguished together with an intermediate group, which was serologically related toNocardia turbataandNocardia caviae. Exo‐antigens of theDermatophilusstrains did not cross‐react with antisera against otherActinomycetales, CorynebacteriumandArthrobacterstrains.

ISSN:0004-945X    

DOI:10.1038/icb.1966.9

出版商:Nature Publishing Group    

年代:1966

数据来源: WILEY

摘要:

SummaryColchicine given parenterally to rats in a dose of 80 μg./100 g. produced atrophic changes in the jejunal mucosa which differed in many respects from those seen in human idiopathic steatorrhoea. Perfusion studies performedin vivoon the third day showed a significant reduction in the rates of absorption of water, sodium and potassium. Both bi‐directional fluxes of sodium were greatly reduced.

ISSN:0004-945X    

DOI:10.1038/icb.1966.10

出版商:Nature Publishing Group    

年代:1966

数据来源: WILEY