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Twenty One

Known as: 21, Twenty-One 
A natural number greater than twenty and less than twenty-two and the quantity that it denotes.
National Institutes of Health

Papers overview

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Highly Cited
2001
Highly Cited
2001
Nuchal Translucency and the Acceptance of Invasive Prenatal Chromosomal Diagnosis in Women Aged 35 and Older
Highly Cited
1994
Highly Cited
1994
Use of the acrosome reaction to ionophore challenge test in managing patients in an assisted reproduction program: a prospective, double-blind, randomized controlled study.
Highly Cited
1984
Highly Cited
1984
Bystander CPR in prehospital coarse ventricular fibrillation.
Highly Cited
1977
Highly Cited
1977
A prospective study of parotid metastases from head and neck cancer.
Highly Cited
1973
Highly Cited
1973
Reconstruction for Medial Instability of the Knee: Technique And Results In Sixty Cases
Sixty patients were treated for medial instability by advancement of the medial collateral ligament and posteromedial capsule as… 
Review
1971
Review
1971
Treatment of gram-negative shock.
Highly Cited
1970
Highly Cited
1970
Epidemic acute glomerulonephritis associated with type 49 streptococcal pyoderma. I. Clinical and laboratory findings.
Highly Cited
1966
Highly Cited
1966
The femorofemoral shunt. An appraisal.
1962
1962
Radiological appearances in pulmonary aspergillosis.
Highly Cited
1933
Highly Cited
1933
A study of the effects of theelin on gonorrheal vaginitis in children
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