0
ARTICLE |

THE NEPHELOMETER:AN INSTRUMENT FOR ESTIMATING THE NUMBER OF BACTERIA IN SUSPENSIONS USED FOR CALCULATING THE OPSONIC INDEX AND FOR VACCINES.

JOSEPH McFARLAND, M.D.
JAMA. 1907;XLIX(14):1176-1178. doi:10.1001/jama.1907.25320140022001f.
Text Size: A A A
Published online

Those who have used the method of Leishman or the later method of Wright for estimating the phagocytic or opsonic indexes of the blood well know that it is essential to use bacterial suspensions containing uniform numbers of bacteria in order to secure uniformity of results. If the suspension used for one estimation contains twice as many bacteria as that used at another the results will vary, though not mathematically, according to the density of suspension.

The method recommended by Wright is ingenious though cumbersome and depends on the actual enumeration of the bacteria contained in the suspension, and is accomplished by mixing a given volume of the bacterial suspension with an equal volume of blood, dropping a diaphragm with a small aperture into the eyepiece of the microscope, and then counting the number of blood corpuscles and bacteria in each of a number of microscopic fields. The computation that

Topics

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

Figures

Tables

References

CME
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.
NOTE:
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).

Multimedia

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.

Jobs
brightcove.createExperiences();