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8. Bohr, C., Hasselbalch, K., Krogh, A. Arch. Physiol. skand. 1904, 16, 402.9. Karp, H. R., Sieker, H. O., Heyman, A. Amer. J. Med. 1961, 30, 861.10. Issued by the British Empire Cancer Campaign, 11, Grosvenor Crescent,

London, S.W.1.

apnoeic period, starting when the PaCO2 and PaO2 werenormal, resulted in a build-up of CO2 and a lowering ofPaO2 which eventually stimulated the sluggish respiratorycentre, the subsequent hyperpnoeic phase correcting theblood gases so that apnoea once again followed.Brown and Plum report that all their patients had

respiratory alkalosis with maximal PaC02 coinciding withpeak dyspnaea and minimal PaC02 with the beginning ofthe apnoeic phase. They found that, compared withnormal subjects, there was an enhanced respiratoryresponse to PaC02 resulting in a rapid blowing-off ofCO2 in the hyperpnceic phase, and this led to the sub-sequent apnoeic phase. With the decrease of the PaCO2the pH rose and as a result of the Bohr effect$the relativeoxygen saturation rose. The PaO2, however, remained lowbecause of the alkalosis and, whereas normally the carotidbody receptors provide little ventilatory stimulation, thiswas not so in patients with C.S.R., in whom the hyper-apnoeic phase continued even when the PaCO2 had fallento low levels.

Karp et al.9 found in the hyperventilation phase adecreased arteriovenous oxygen difference, comparedwith that of the apnoeic phase, from which they deducethat in the hyperventilation phase cerebral blood-flow isincreased. They point out that this decreased arterio-venous oxygen difference is unlikely to indicate reducedoxygen utilisation by the brain, because they recorded inthe hyperventilation phase a correspondingly increasedmental alertness, more normal electroencephalographictracings. Moreover, they found a decreased cerebralcirculation-time. Relating the changes in the arterial

blood-gas tensions to the ventilatory and apnoeic phasesof c.s.R., they suggest that the hypoxaemia and increasein the PaCO2 in the ventilatory phase are probablyresponsible for cerebral vasodilatation and hence increasedcerebral blood-flow. They conclude that the varyingblood-flow may be one more manifestation of the phasicactivity in the central nervous system responsible for c.s.R.

BRITISH EMPIRE CANCER CAMPAIGN

THE report for 1960 of the British Empire CancerCampaign 10 describes the work in some forty institutesfinanced either wholly or partly by grants totalling almostSl.000,000. Two main themes emerge: chemotherapywith various alkylating agents, and radiotherapy withassociated work in radiobiology and radiation chemistry.From the clinical point of view there is little that is

new on the use of alkylating agents; but the intensivefundamental research now in progress may eventuallylead to improvements in the selectivity and effectivenessof compounds of this type.As regards radiotherapy, a great deal of interest is

centred on the effect of oxygen tension on the response ofnormal and neoplastic cells to X rays. An extensive

investigation on the long-term effects of a single whole-body irradiation in mice is reported from the departmentof physics at St. Bartholomew’s Hospital, London.Leukaemia accounted for the largest percentage increase ofdisease, with pulmonary tumours sharing the largestdecrease. These changes in incidence are due to changesin the time of onset; and, with correction for this changein time, the percentage incidence of all causes of death is

the same in the irradiated mice as in the controls. It isconcluded that radiation shortens life, not by inducingspecific diseases, but by bringing all causes of death for-ward in time without altering the relative risks, and it issuggested that radiation is a common causal factor in awide variety of diseases, rather than a specific carcinogen.Other carcinogens may possibly act in a similar fashion, byaccelerating the development of neoplasms rather than byproducing them.On the vexed question of the correlation between

medical X rays and leukaemia. Dr. Alice Stewart reportsthat there are two distinct xtiological varieties of

leukaemia, only one of which is numerically important inchildhood. This type occurs in children who are especiallyprone to pneumonia and other pyogenic infections-whichexplains a previous finding that in the leuksemic groupstudied pneumonia was given as a reason for X rays moreoften than in other groups. It is suggested that there is apremalignant defect in the genes which control the develop-ment of the reticulo-endothelial system, and that theabnormal stem cells derived from these genes undergofurther changes and become malignant. Before the

discovery of antibiotics these children might have died ofpneumonia. Nowadays, if the infection is survived, thechildren may die of leukaemia. The second type ofleuksemia in children ? rare and may be caused byirradiation in utero.

Reports from several centres suggests that stalematehas been reached as far as the endocrine treatment ofcancer is concerned. Enough large series of patients havebeen studied to provide a clear idea about the clinicalusefulness of the various forms of such treatment, butthere is still little direct experimental evidence concerningthe mechanisms by which these affect the course of thedisease. Emmens and his colleagues in Sydney report thatthe most potent antioestrogen so far found in their work isdimethyl stilboestrol and a clinical trial of the effectivenessof this compound in mastitis is in progress.The overall impression from the report is that there is

no sign of a fundamental discovery which holds out anypromise of a new era in the treatment of cancer. Rather,the impression is one of inching forward by vast. andpainful effort.

ACADEMIC CHANGES IN NEW ZEALAND

THE University of New Zealand is to disappear at theend of this year, and, in preparation for this honourabledissolution, it has already handed over its examiningpowers to its component institutions the University ofOtago at Dunedin, the University of Canterbury, theVictoria University of Wellington, and the Universityof Auckland.The University of Auckland has been designated as the

seat of New Zealand’s second medical school-there is

already one at Dunedin-and Sir Douglas Robb, F.R.C.S.,has been elected chancellor. As yet the Government hasnot authorised the launching of the school, but the

university has lately set up a faculty of medicine to

coordinate existing postgraduate facilities and to preparethe way. A steering committee has been studying theproblem for over two years, and the Auckland MedicalResearch Foundation, set up in 1957, will be of greatassistance.

Mr. A. C. H. BELL has been re-elected president of theRoyal College of Obstetricians and Gynxcologists.