THE USE OF GLASS CAPILLARY TUBES AS DISPOSABLE MICROBORE COLUMNS FOR RP-HPLC OF PROTEINS AND PEPTIDES

“The viscosity of the blood in narrow capillary tubes” by Robin Fåhraeus and Torsten Lindqvist ( Am J Physiol 96: 562–568, 1931) can be a valuable opportunity for teaching basic hemorheological principles in undergraduate cardiovascular physiology. This classic paper demonstrates that a progressive decline in apparent viscosity occurs when blood flows through glass capillary tubes of diminishing radius, which was later designated as the “Fåhraeus-Lindqvist effect.” Subsequent studies have shown that apparent viscosity continues to decline at diameters that correspond to the arteriolar segments of the systemic vascular tree, where the majority of the total peripheral resistance resides and is actively regulated in vivo. The Fåhraeus-Lindqvist effect thus reduces microvascular resistance, thereby maintaining local tissue perfusion at a relatively lower blood pressure. The paper by Fåhraeus and Lindqvist can be used as a platform for a plenary discussion of these concepts as well as of the relationships among hematocrit, vessel diameter, red blood cell deformability, and resistance to blood flow and how these factors may affect the work of the heart.

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A Simple Method for Determination of Plasma Thiocyanate

Annals of Clinical Biochemistry International Journal of Laboratory Medicine ◽

10.1177/000456328802500418 ◽

1988 ◽

Vol 25 (4) ◽

pp. 422-423 ◽

Cited By ~ 4

Author(s):

M Falkensson ◽

P Lundquist ◽

H Rosling ◽

B Söurbo

Keyword(s):

Sodium Hypochlorite ◽

Perchloric Acid ◽

Coupling Agent ◽

Barbituric Acid ◽

Field Conditions ◽

Glass Capillary ◽

Capillary Tubes ◽

Simple Method

We describe a method for the determination of thiocyanate in plasma from blood collected under field conditions in heparinised glass capillary tubes. After deproteinisation of plasma with perchloric acid, thiocyanate is directly determined colorimetrically by the König reaction with sodium hypochlorite as the chlorinating reagent and barbituric acid as the coupling agent. This simple method cannot be applied to urine as the latter contains interfering compounds.

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X-ray Capillary Microbeam Spectrometer

Advances in X-ray Analysis ◽

10.1154/s0376030800020097 ◽

1989 ◽

Vol 33 ◽

pp. 623-628 ◽

Cited By ~ 2

Author(s):

S. Larsson ◽

P. Engstrom ◽

A. Rindby ◽

B. Stocklassa

Keyword(s):

Trace Elements ◽

Trace Element ◽

Optical Microscope ◽

X Rays ◽

Glass Capillary ◽

Capillary Tubes ◽

X Ray

AbstractBy utilizing the total reflecting properties of x-rays inside glass capillary tubes, intensive fine- or microbeams of x-rays can be attained. By using a conventional x-ray tube in combination with capillary technique, microbeams with a diameter of a few μm and with an intensity sufficient for trace elements, analyses have been achieved. By moving the sample, lineand areascan can be performed and trace element information can be directly superimposed on a micrograph from a built-in optical microscope.The background of the capillary technique is reviewed and an EDXRF microbeam spectrometer for trace elements is described. Examples of applications for the microbeam spectrometer are given.

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