The Purification and Mechanism of Action of Human Antithrombin-Heparin Cofactor

Isoelectric focusing in immobilized pH gradients: Principle, methodology and some applications☆

The nerve growth factor protein was purified over 100-fold from adult mouse salivary glands. The first step was a gel filtration on Sephadex G-100 at pH 7.5 of the aqueous gland extract. After gel filtration, most of the NGF activity was eluted in the 80,000-90,000-molecular-weight region (G-100 pool). The G-100 pool was dialyzed at pH 5.0 and fractionated by CM52 cellulose chromatography at pH 5.0. Recovery from CM52 cellulose columns was quantitative for protein and ranged 80-100 per cent for the nerve growth factor activity; the latter was almost completely carried by a protein which did not show any heterogeneity when examined by several analytical tests. The purified nerve growth factor showed an S20,w = 2.43, a D20,w = 7.30 and a 30,000 molecular weight. The over-all recovery was about 45 per cent.

https://www.pnas.org/content/pnas/64/2/787.full.pdf

The nerve growth factor: purification as a 30,000-molecular-weight protein

In this paper we report a first experiment using a new computer-based technique to identify clusters of highly interactive documents in science. We contend that these clusters represent the scientific specialties which currently exhibit high levels of activity. This technique, we believe, opens the way to a systematic exploration of the entire specialty structure of science, including both the internal structure of specialties and their relationship to one another. That science is a mosaic of specialties, and not a unified whole, either socially or intellectually, is a frequently made assumption, but only recently has this infra-structure of science become the subject of systematic study. Most scientists have intuitive notions about the subdivisions of their fields, but no observer, however broadly trained, can gain an overall perspective on the scientific mosaic. A series of recent studies has called attention to the importance of specialties as 'building blocks' of science. Crawford's paper' described how one specialty, sleep research, is effectively organized as a communication system around certain key individuals and research centres. Griffith and Mullins2 have argued that major changes in a variety of disciplines have been generated within small, socially coherent groups. *325 Chestnut Street, Philadelphia, Pennsylvania, I 9I o6, USA.

The Structure of Scientific Literatures I: Identifying and Graphing Specialties:

Free zone electrophoresis

/pdf/isoelectric-fractionation-analysis-and-characterization-of-3waqxd24vo.pdf

Isoelectric fractionation, analysis, and characterization of ampholytes in natural pH gradients. IV. Further studies on the resolving power in connection with separation of myoglobins.

Vesterberg O

Papers

Isoelectric fractionation, analysis, and characterization of ampholytes in natural pH gradients. IV. Further studies on the resolving power in connection with separation of myoglobins.