ISSN:0022-1945    

DOI:10.1080/09291017109359284

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

The distribution of the months of birth of children with congenital dislocation of the hip (CDH) in six countries in the Northern Hemisphere and in Victoria (Australia) were compared. The quarterly and monthly patterns of the six Northern Hemisphere countries were found to be in agreement: i.e. less children with CDH were born during the months of March through August than during September through February with peak incidence from the end of October till mid‐January. A reversed pattern of CDH births was noted in Victoria with maximum frequency in the second quarter of the year and a trough in the first quarter. Temperature per se could not be considered responsible for the variations in CDH births in both Hemispheres. Huntington ‘s hypothesis of a “basic animal rhythm” operating in man seems a reasonable explanation.

ISSN:0022-1945    

DOI:10.1080/09291017109359285

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

The photoperiodic induction of gonadal growth in coturnix (Japanese quail) was studied in relation to the existence of a daily photosensitive phase. A cycle of 14 hrs of dim green light and 10 hrs of darkness was used to synchronize activity rhythms of three groups of birds. In addition to this treatment, the second group of quail received a 3‐hr pulse of white light at the beginning of the green phase, and another group was given a 3‐hr light pulse at the end of the green phase. A fourth group was maintained in total darkness for 16 weeks. The control group for each experiment was given 14 hrs of white light and 10 hrs of darkness daily. Control birds reached sexual maturity before 8 weeks of age. Some quail kept in total darkness were sexually mature by 10 weeks of age. Significant differences in sexual maturation were not apparent among the three groups of birds receiving 14 hrs of dim green light daily, two of which were given white light pulses either at the beginning or at the end of the green phase, although a trend favored the group with early light

ISSN:0022-1945    

DOI:10.1080/09291017109359286

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

The actographically recorded locomotor activity and the plasma corticosterone content were measured in male quail, which had been first preadapted to a control 12L/12D photoperiod, and then switched for 4 weeks to ahemeral photoperiods of 35 hrs (26L/9D) or (9L‐26D), or 13 hrs (6L/7D).

ISSN:0022-1945    

DOI:10.1080/09291017109359287

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

A circadian rhythm in gastric content is reported in normal mice. The high values appear in the middle of the activity (dark) period and the trough figures are seen at the end of the rest (light) period. The rhythm appears delayed during the first 24‐hr period after hepatectomy but reappears with its normal timing during the second 24‐hr period.

ISSN:0022-1945    

DOI:10.1080/09291017109359288

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

1.Circadian rhythms (activity, temperature, urine and microfilariae) were investigated in dogs, cat, hen, duck,Thamnomys, andGerbillus. They differed greatly among themselves and also from those of Macaca monkeys or man.2.In dogs and cats (hunting animals) activity was not organized according to the light/dark cycle but it occurred in irregular bouts lasting up to 4–6 hrs at all times of the day and night. The temperature (in a cat) was similarly irregular, going up in peaks lasting an hour but not clearly associated with light/dark. (This is in great contrast to the rhythms of monkeys and man which are closely associated with light). Recordings of urinary excretion in dogs showed daily rhythms of low amplitude with a tendency for higher excretory rates to occur during the normal period of darkness.3.The microfilariae ofDirofilaria immitisin the dogs showed only a moderately defined cycle and this was not significantly affected by continuous darkness or continuous light.4.The hen showed well marked cycles of activity and body temperature, which were high by day and low by night. These resemble the cycles of monkeys and man.5.The duck showed no clear cycles and its activity or body temperature, although both tended to be higher by day than by night.6.Thamnomys surdaster(the Congo tree rat) andGerbillusshowed good cycles of activity which were high by night and low by day. These were as well defined as those of monkeys, only the phases were reversed.7.The differing circadian rhythms of the different hosts are clearly important for the study of the cycles of parasites (microfilariae, plasmodia, etc.) which they may harbour.

ISSN:0022-1945    

DOI:10.1080/09291017109359289

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

Rhesus monkeys(Macaca mulatta)were subjected to several, successively applied, environmental conditions. Their activity was monitored by means of ultra‐sonic movement detectors, and the data were submitted to a least sqares spectral analysis.

ISSN:0022-1945    

DOI:10.1080/09291017109359290

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

ISSN:0022-1945    

DOI:10.1080/09291017109359283

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor