causing airway relaxation.

"A deep inspiratory maneuver is one of the most severe dynamic
stresses that lungs normally experience. It is typically a very
transient phenomenon. When one takes a sigh, the timing is such that
the whole maneuver is over in about 1 to 3 s."

Surely a sigh is done while breathing out, not in. They probably mean a
gasp.

"Six dogs [do dogs sigh?] weighing approximately 20 kg each were
anesthetized with thiopental (15 mg/kg induction dose followed by by
(sic) 10 mg/kg/h intravenous maintenance dose)."

Why should dogs be forced to get asthma?  Keep an eye on any pets you
have such as dogs or even goldfish lest some nerd, not getting enough
cash from sales of the so very unexpectedly ineffective asthma drugs,
needs them for "asthma research".

"In summary, we have shown that airways contracted with MCh (chemical
used in provocation test, diagnosis) fail to dilate at the same rate as
the lung parenchyma during rapid lung inflation. This effect may play a
role in the unique response of asthmatic subjects to deep inspiration.
The mechanism of this dynamic slowness of contracted airways probably
involves intrinsic properties of the smooth-muscle contractile
processes."

Anyway, concentrating on doing a genuine deep inspiration with
contraction and upward movement of the abdomen at navel level and chest
expansion, may lead to a normal invigorating deep breath with patience.
The chest is unlocked and the shoulders go up.  That's my experience.

A further mystery of asthma research is the stubborn refusal to analyze
the so effective oriental breathing tricks.   The Vikings in Greenland
were supposed to have died out because as part of their national
identity they were too proud to eat fish and seals like the Eskimos.
Regards, Richard Friedel

See http://yglesias.typepad.com/matthew/2004/12/mmmfish.html
"The problem was that the Norse simply couldn't adapt to the
country's changing environmental conditions. Diamond writes, for
instance, of the fact that nobody can find fish remains in Norse
archeological sites. One scientist sifted through tons of debris from
the Vatnahverfi farm and found only three fish bones; another
researcher analyzed thirty-five thousand bones from the garbage of
another Norse farm and found two fish bones. How can this be? Greenland
is a fisherman's dream: Diamond describes running into a Danish
tourist in Greenland who had just caught two Arctic char in a shallow
pool with her bare hands."