摘要:

SUMMARYAfter an epidemic of dengue‐like fever in Townsville in 1952, investigations were made to try to determine the possible vectors of the virus from the presumptive reservoir of flying foxes and/or migratory birds of the seashore to man. This was done by determining which mosquito species had fed upon flying foxes, upon birds, and upon man.Two thousand and twenty female mosquitoes of 32 species were collected, either attracted to bait (man, horse and flying fox), were caught in light traps, or recovered from resting sites. Of these mosquitoes, 713 were engorged with blood and precipitin‐tested to determine the hosts upon which they had fed. The range of hosts was man, horse, ox, dog and fowl.Only five species,T. uniformis, A. vigilax, C. annulirostris, C. fatigansandC. sitienswere implicated as being possible vectors of the virus from the presumed reservoir to man, and of them the prime suspects wereA. vigilaxandC. sitiens, for these two species were attracted to flying fox bait, they had fed upon both man and fowl and they were associated with mangrove swamps, in which flying foxes “camp” during the day and in which migratory birds of the seashore roost at night.These findings are discussed with regard to the implicated vectors of Murray Valley encephalitis and Japanese B encephalitis, both of which are immunologically related to dengue fever.

ISSN:0004-945X    

DOI:10.1038/icb.1960.1

出版商:Nature Publishing Group    

年代:1960

数据来源: WILEY

摘要:

SUMMARYA method for the determination of selenium in trace quantities in a variety of animal and plant tissues is described. The method makes use of the fluorescence of the seleniumdiamino benzidine complex in hydrocarbon solvents. Determination of as little as 0·02 μg selenium is possible and the method has been routinely used for estimations in the range 0·1–2·0 μg selenium.

ISSN:0004-945X    

DOI:10.1038/icb.1960.2

出版商:Nature Publishing Group    

年代:1960

数据来源: WILEY

摘要:

SUMMARYComplement‐fixing antibodies toCoxiella burnetiwere present in 23 p.c. of kangaroos collected in western Queensland, and agglutinins in 15 p.c. Red kangaroos,Megaleia rufa, showed a higher incidence of complement‐fixing antibodies (33 p.c.) than grey kangaroos,Macropus major(12 p.c.). In three areas, the incidence of complement‐fixing antibody inM. rufawas between 46 and 54 p.c.C. burnetiwas isolated in mice from the blood of oneMacropus major.Thirteen isolations were made from nearly 3,000 ornate kangaroo ticks,Amblyomma triguttatum, collected from kangaroos, goats and sheep. The titre of infectivity of infected ticks for mice was usually in the range 10−6to 10−9.Infection of kangaroos and A.triguttatumwas found over a considerable area, between 24 and 28° S. and 144 and 149° E., in western Queensland.It thus seems probable that a natural kangaroo‐tick cycle exists. The three‐host life cycle and wide host range of this tick would allow it to spread infection to domestic animals as well as kangaroos. Infestation of sheep would bring infected ticks into contact also with workers in the sheep‐shearing industry, and was probably responsible for recent outbreaks of Q fever among them.

ISSN:0004-945X    

DOI:10.1038/icb.1960.3

出版商:Nature Publishing Group    

年代:1960

数据来源: WILEY

摘要:

SUMMARYAppropriately timed afferent stimulation of one olfactory bulb can depress afferent induced activity in the opposite bulb, the depression being mediated by the true commissural component of the anterior commissure which is part of the olfactory efferent system. Bulbar retrograde responses evoked by lateral olfactory tract stimulation are depressed by continuous high frequency stimulation of the anterior commissure, and this is considered to be further evidence for a depressive action of the efferent system in the olfactory bulb. Stimulation of the efferent system evokes monophasic negative waves in the bulb which, on continuous stimulation, summate to give a sustained negativity. The appearance of this negative shift is correlated with the onset of the depressive influence. Lateral olfactory tract stimulation evokes polyphasic, dominantly positive, waves in the bulb which do not summate but rapidly fatigue on repetitive stimulation at high frequencies.

ISSN:0004-945X    

DOI:10.1038/icb.1960.4

出版商:Nature Publishing Group    

年代:1960

数据来源: WILEY

摘要:

SUMMARYVarious haematological observations were made on Central Australian aborigines. One group contained some 30 nomadic males living under primitive conditions for most of the year. The second group consisted of about 20 males and 15 females living under urban conditions, on an almost European diet. The nomadic group's diet had a high iron content. The haemoglobin levels of a control group of Europeans in Central Australia were also measured.The haemoglobin and haematocrit values of the nomads were higher than those of the Bungalow males. Both sexes at the Bungalow did not differ significantly from European controls. The erythrocyte counts showed no significant difference between the two male groups. The haemoglobin levels of a group of 16 Europeans living at Alice Springs were almost the same as those of the Bungalow males.The M.C.V's and M.C.H's of the nomads were just greater than those of Europeans, but the Bungalow groups did not differ significantly from either the nomads or Europeans. The M.C.H.C's did not differ significantly between the groups or from European standards.Erythrocyte osmotic fragility studies showed an increase in haemolysis at ‐5N but otherwise were not significantly different from those of Europeans. The aborigines did not differ significantly among themselves.The erythrocyte sedimentation rates were quite raised in all groups of aborigines when compared with Europeans. However, the nomads’ values were less than those of the urban groups.

ISSN:0004-945X    

DOI:10.1038/icb.1960.5

出版商:Nature Publishing Group    

年代:1960

数据来源: WILEY

摘要:

SUMMARYThe hot‐plate method has been used on mice to investigate the effect of amiphenazole on the analgesic activity of morphine. Over a range of doses of each, morphine analgesia is potentiated by amiphenazole. The phenomenon has been observed with oral, intraperitoneal and subcutaneous routes of administration. In addition, morphine at a dose producing only slight analgesia potentiates the mild analgesic action of amiphenazole.The effects of amiphenazole on codeine analgesia have been variable; at most, mixtures of the two drugs have shown a moderate but brief increase of analgesic effectiveness over that of the components given alone.It is suggested that the morphine‐potentiating property of amiphenazole may allow satisfactory clinical analgesia with doses of morphine less than those customary.

ISSN:0004-945X    

DOI:10.1038/icb.1960.6

出版商:Nature Publishing Group    

年代:1960

数据来源: WILEY

摘要:

SUMMARYBoth the haemagglutinin and the complement fixing antigen of ectromelia virus are fairly stable at hydrogen ion concentrations ranging from pH 4 or 5 to 11, although the highest titres were found around the neutral point.Ectromelia complement fixing antigen showed some drop in titre on heating at 56°C. for 30 minutes, but no more so than vaccinial preparations run in parallel.The haemagglutinin seems to have a heat labile as well as a heat stable component. The heat labile component was neutralised by rabbit anti‐serum but not by normal rabbit serum and so appears to be specific.

ISSN:0004-945X    

DOI:10.1038/icb.1960.7

出版商:Nature Publishing Group    

年代:1960

数据来源: WILEY

摘要:

SUMMARYFollowing lethal whole body irradiation and homologous embryonic haemopoietic grafting, transplantation of the matured grafted material was made into further lethally irradiated test animals with the object of demonstrating tolerance. This has been judged by the ability of such transplanted material to avoid secondary disease in a foreign host environment.

ISSN:0004-945X    

DOI:10.1038/icb.1960.8

出版商:Nature Publishing Group    

年代:1960

数据来源: WILEY

摘要:

SUMMARYChlorpromazine (0·46–0·7 mg./kg. i.v.) caused profound fall of haematocrit in sheep. Its virtual abolition by splenectomy and its inverse relationship to splenic gamma radiation surface counts in intact sheep prepared with51Cr‐labelled red cells showed this to be due almost entirely to splenic relaxation and consequent increase of red cells held there. Plasma dilution through water shift played only a small part in the haematocrit fall Similar haematocrit fall, and its virtual abolition by splenectomy, occurred after dihydroergotamine but not after Dibenamine. Both these agents, as well as chlorpromazine, were shown to reduce the haematocrit response to adrenaline ornor‐adrenaline. Haematocrit fall also occurred after pentobarbitonum sodium at a dose sufficient to produce obvious central effects. The relative importance of ataraxis and of splenic adrenergic blocking in the haematocrit‐reducing effect of chlorpromazine in sheep could not be wholly resolved, but the central effects are probably more important. Haematocrit fall, abolished by splenectomy, was also observed after mepazine (2·3 mg./kg. i.m.). The effect after meprobamate (9·4 mg./kg.) was slight.

ISSN:0004-945X    

DOI:10.1038/icb.1960.9

出版商:Nature Publishing Group    

年代:1960

数据来源: WILEY