28.4 Correspondence NR 25/4/05 4:57 pm Page 1067
correspondence
A drug is effective if better than a harmless controlValid trials can still be held, as with HIVNET 012, when ethics rules out a placebo group. Sir — In his Correspondence letter “HIV
is not harmful (thus replacing a placebo),
the effectiveness of the experimental drug
trial” (Nature 434, 137; 2005), Valendar
Turner asks on what basis it can be claimed
et al. Lancet 353, 773–780; 1999).
course of zidovudine was used as the active
is effective in reducing mother-to-infant
to be enrolled in the two active drug arms,
control. Many studies had already reported
Institutes of Health, the French National
birth before discontinuation of the placebo
the high variability in reported historical
arm, the transmission rate at 6–8 weeks
group and 7% in the nevirapine group.
(The 6–8-week transmission rates at the
US Institute of Medicine panel — between
placebo in other studies starting at least
similar in efficacy, it is not possible to
effective or equally ineffective — unless
and a single dose to the baby shortly after
there is clear evidence that the control
birth), or a very short course of zidovudine
from the onset of labour through the first
Brooks Jackson*, Thomas Fleming†
week of the baby’s life, or a placebo.
the active control has not been established
*Johns Hopkins School of Medicine, 600 NorthWolfe Street, Baltimore, Maryland 21287, USAUniversity of Washington, Box 357232,
that a short course of zidovudine, given
found to be superior to a control that itself
DNA barcoding does not Nice planet, shame about
on the study of curated voucher specimens,
compete with taxonomy
high-resolution digital images, collection
the human race
locality data and other information. Sir — M. C. Ebach and C. Holdrege, in
Sir — Inspired by Stephen Baxter’s Futures
story “Under martian ice” (Nature 433,
substitute for taxonomy” Nature 434, 697;
668; 2005), we began to discuss the Fermi
2005), express some key misunderstandings
paradox: that if aliens exist, they would
been funded by agencies that do not have
have visited everywhere by now, including
coding programme would — and especially
a tradition of supporting taxonomic work.
are already achieving positive results, albeit
be a ‘big science’ programme, and as such
on a relatively small scale. If implemented
of similar scale from physics, medicine and
the Universe is the way it is because we
are here to observe it — we propose the
directed toward the collection and curation
misanthropic principle as the resolution
classification, and thus differs fundamentally
Randall D. Kamien, Madhuri Kaul Department of Physics and Astronomy,
has the potential to inject significant new
209 South 33rd Street, University of Pennsylvania,
species within previously unstudied taxa. T. Ryan Gregory correspondence Department of Integrative Biology, University of
Contributions to Correspondence may be submitted
Guelph, Guelph, Ontario N1G 2W1, Canada
to [email protected].
NATURE | VOL 434 | 28 APRIL 2005 | www.nature.com/nature
2005 Nature Publishing Group
2005 Nature Publishing Group
FOUSMC03_0131134604.QXD 12.16.03 6:58 PM Page 49 RKAUL-15 RKUAL-15:Desktop Folder:PURAN_FOUST_16_12:CH03: Calculating the cc’s LEARNING THE FORMULA Now that the first two steps of this formula have been learned—identifyingand calculating the desired dose, and calculating the concentration—we canproceed to the third step. STEP 3 Calculate the amount of cc’s to be delivered.The
PRACTICE GUIDELINE RECOMMENDED DRUGS FOR EMERGENCY CENTRES This Practice Guideline sets out the recommended drugs to be held in an Emergency Centre. The following emergency drugs and IV solutions are listed as essential (must all be available, together with protocols addressing their use) and recommended (EMSSA recommends that the Emergency Centre holds these drugs, along with pr