After WWII until the end of the 20th century (accumulation of modern knowledge) As the world was recovering from the complex dramatic events of the 1930s and the terrible WWII, it became more practical. Research tools and technologies of another level appeared. Thanks to these technologies, it became understandable what really occurs inside cells and between them (for example, the model of double helix of DNA was created in 1953). At the same time the changed ethical norms did not allow to conduct cardinal experiments on humans, as it was possible in previous decades , and the influence of different factors could be estimated only implicitly .
After WWII until the end of the 20th century (accumulation of modern knowledge) After WWII, research tools and technologies of another level appeared. Thanks to these technologies, it became understandable what really occurs inside cells and between them (for example, the model of the DNA double helix was created in 1953). At the same time , changed ethical norms did not allow cardinal experiments to be performed on humans, as had been possible in previous decades . Consequently, the influence of different factors could be estimated only indirectly .
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As the world was recovering from the complex dramatic events of the 1930s and the terrible WWII, it became more practical. Research
After WWII, research
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double helix of DNA
the DNA double helix
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the
,
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to conduct cardinal experiments
cardinal experiments to be performed
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it was
had been
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, and
. Consequently,
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implicitly
indirectly