JAMA. 1948;138(8):595. doi:10.1001/jama.1948.02900080053011.
Text Size: A A A
Published online

Shorb1 in 1947 reported finding in refined liver extracts a factor required by Lactobacillus lactis Dorner (L. L. D. factor) which was present in an almost linear relationship to the unit potency of the extracts used in the treatment of pernicious anemia. Rickes2 and his associates have isolated from liver a crystalline compound, vitamin B12, and Shorb, who assayed its potency value for L. lactis Dorner, considered it to be either wholly or partially responsible for the L. lactis Dorner growth activity observed for liver extracts. West3 reported a positive hematologic response in 3 patients with pernicious anemia following the intramuscular administration of vitamin B12 in single doses of 3, 6 and 150 micrograms. Spies,4 in 1948, reported on the use of crystalline vitamin B12 in the treatment of addisonian pernicious anemia in 2 cases, nutritional macrocytic anemia in 2 cases and nontropical


Sign In to Access Full Content

Don't have Access?

Register and get free email Table of Contents alerts, saved searches, PowerPoint downloads, CME quizzes, and more

Subscribe for full-text access to content from 1998 forward and a host of useful features

Activate your current subscription (AMA members and current subscribers)

Purchase Online Access to this article for 24 hours

First Page Preview

View Large
First page PDF preview




Meets CME requirements for:
Browse CME for all U.S. States
Accreditation Information
The American Medical Association is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The AMA designates this journal-based CME activity for a maximum of 1 AMA PRA Category 1 CreditTM per course. Physicians should claim only the credit commensurate with the extent of their participation in the activity. Physicians who complete the CME course and score at least 80% correct on the quiz are eligible for AMA PRA Category 1 CreditTM.
Note: You must get at least of the answers correct to pass this quiz.
You have not filled in all the answers to complete this quiz
The following questions were not answered:
Sorry, you have unsuccessfully completed this CME quiz with a score of
The following questions were not answered correctly:
Commitment to Change (optional):
Indicate what change(s) you will implement in your practice, if any, based on this CME course.
Your quiz results:
The filled radio buttons indicate your responses. The preferred responses are highlighted
For CME Course: A Proposed Model for Initial Assessment and Management of Acute Heart Failure Syndromes
Indicate what changes(s) you will implement in your practice, if any, based on this CME course.
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).


Some tools below are only available to our subscribers or users with an online account.

Sign In to Access Full Content

Related Content

Customize your page view by dragging & repositioning the boxes below.