TOP 100 SCIENCE SITES
| |||
|
| |||
| |||
|
| |||
| Viagra: The profitable pill When Pfizer launched Viagra in 1998 its share price doubled within days. Since then, the little blue pills have become a pillar of profit, earning the company more than ÂŁ1bn a year.Thanks to promotional campaigns, which included appearances by the footballing legend Pele, male impotence lost some of its stigma and 25 million men requested the pills. In England alone, GPs write about 6m Viagra prescriptions a year.The drug started life in a lab in Sandwich, Kent, where it was developed to treat high blood pressure. Its transformation into a blockbuster treatment for impotence began when volunteers in a clinical trial reported a suspicious number of erections. The overnight success of Viagra prompted Pfizer to wonder if the drug had any effect in women. They raised awareness of a condition called "female sexual arousal disorder", an all-encompassing phrase for sexual dysfunction, and began clinical trials. The trials were a failure and the attempt to have Viagra licensed for the condition was abandoned.Pfizer has been criticised for overstating the benefits of Viagra. It claims "more than half of all men over 40 have some difficulty getting and maintaining an erection". In 2004, the US Food and Drug Administration forced Pfizer to pull a series of advertisements because it made unsubstantiated claims about the drug's effectiveness.Some psychologists warn Viagra has become a lifestyle drug that encourages people to neglect underlying mental or physiological problems that can cause impotence. The anti-obestity drug, orlistat, came under fire for similar reasons. Critics said it fostered the misconception that modern ills can be dealt with by a pill instead of living a healthier life.Pharmaceuticals industryDrugsReproductionMedical researchSexual healthIan Sampleguardian.co.uk © Guardian News & Media Limited 2009 | Use of this content is subject to our Terms & Conditions | More Feeds guardian.co.uk |
Darwin did get there before Wallace? Alfred Venables, Julian Wimpenny and David Lloyd (Letters, December 3) suggest that Alfred Russel Wallace "has a stronger claim to the theory of evolution than has Darwin", and imply that there is something suspect in Charles Darwin's reaction to the 1858 letter from Wallace. This is contradicted by well-documented facts.The development of Darwin's thoughts on evolution can be traced in his notebooks of 1836-38, published in 1987 by Cornell University Press. These show that he had arrived at the theory of evolution by natural selection in 1838, fully 20 years before Wallace. In 1844 he wrote a detailed "sketch" of his ideas, which was communicated to Joseph Hooker. He had also discussed his ideas with Charles Lyell. He had intended to write a much larger work than The Origin of Species, but was stimulated by Wallace's letter into first publishing a short paper alongside Wallace's in 1858, and then into writing the Origin.He followed this up with many other major books, the ideas for which are also recorded in his notebooks. It is well known that others before Darwin and Wallace had proposed the idea of evolution, and of natural selection. Darwin's unique contribution was to marshal a wide range of evidence from the natural history of his time, supporting evolution as a historical process and natural selection as its main cause. Valuable as Wallace's contributions to biology were, there is no doubt that they are overshadowed by Darwin's range of insights into questions that the theory of natural selection could illuminate, and his mastery of the facts.Brian CharlesworthDeborah CharlesworthEdinburghCharles DarwinEvolutionguardian.co.uk © Guardian News & Media Limited 2009 | Use of this content is subject to our Terms & Conditions | More Feeds guardian.co.uk |
In New Way to Edit DNA, Hope for Treating Disease Scientists might have a new way to alter human DNA if a technique for editing the genetic text proves safe and effective. feeds.nytimes.com |
The Doctor's World: For F.D.R. Sleuths, New Focus on an Odd Spot A new book, “F.D.R.’s Deadly Secret,” revives an intriguing theory about a medical mystery around the 32nd president that persists to this day. feeds.nytimes.com |
Sunflower DNA map could produce plants for fuel SIOUX FALLS, S.D. (AP) -- A $10.5 million research project aimed at mapping the DNA sequence of sunflowers could one day yield a towering new variety for both food and fuel.... hosted.ap.org |