Inert gas and raised pressure: evidence that motor decrements are due to pressure per se and cognitive decrements due to narcotic action

1997 ◽  
Vol 433 (6) ◽  
pp. 788-791 ◽  
Author(s):  
J. H. Abraini
Keyword(s):  
Inert Gas ◽  
Per Se ◽  
Narcotic Action

Effect of decompression per se on nitrogen elimination

1978 ◽  
Vol 45 (6) ◽  
pp. 916-921 ◽  
Author(s):  
B. A. Hills
Keyword(s):  
Guinea Pigs ◽  
Driving Force ◽  
Free Breathing ◽  
Inert Gas ◽  
Body Tissue ◽  
Supersaturated Solution ◽  
Random Manner ◽  
Per Se ◽  
Nitrogen Elimination

The elimination of nitrogen from each of 10 unanesthetized guinea pigs has been monitored after switching to a nitrogen-free breathing mix (normoxic He:O2), either without decompression or on decompression to 2.21 or 1 ATA, following an exposure of 2 h at 4 ATA on normoxic N2;O2. Normoxic conditions were maintained throughout to avoid vasomotor effects of oxygen that could have complicated interpretations derived from previous studies. Results confirmed that inert gas washout rates decrease with decompression per se. This can be explained simply on the basis of the decrease in driving force for nitrogen elimination caused by depositing gas into bubbles where they form in tissue in a somewhat random manner. A very rough estimate shows that about 83% of all body tissue retained its gas in supersaturated solution on decompression to 2.21 ATA but only 79% did so at 1 ATA.

Pulmonary gas exchange in diving

2009 ◽  
Vol 106 (2) ◽  
pp. 668-677 ◽  
Author(s):  
R. E. Moon ◽  
A. D. Cherry ◽  
B. W. Stolp ◽  
E. M. Camporesi
Keyword(s):  
Gas Phase ◽  
Mechanical Load ◽  
Work Of Breathing ◽  
Volume Ratio ◽  
Inert Gas ◽  
Respiratory Drive ◽  
Gas Density ◽  
Airways Resistance ◽  
Per Se ◽  
Related Increase

Diving-related pulmonary effects are due mostly to increased gas density, immersion-related increase in pulmonary blood volume, and (usually) a higher inspired Po2. Higher gas density produces an increase in airways resistance and work of breathing, and a reduced maximum breathing capacity. An additional mechanical load is due to immersion, which can impose a static transrespiratory pressure load as well as a decrease in pulmonary compliance. The combination of resistive and elastic loads is largely responsible for the reduction in ventilation during underwater exercise. Additionally, there is a density-related increase in dead space/tidal volume ratio (Vd/Vt), possibly due to impairment of intrapulmonary gas phase diffusion and distribution of ventilation. The net result of relative hypoventilation and increased Vd/Vt is hypercapnia. The effect of high inspired Po2 and inert gas narcosis on respiratory drive appear to be minimal. Exchange of oxygen by the lung is not impaired, at least up to a gas density of 25 g/l. There are few effects of pressure per se, other than a reduction in the P50 of hemoglobin, probably due to either a conformational change or an effect of inert gas binding.

The biological effects of high pressures: underlying principles

1984 ◽  
Vol 304 (1118) ◽  
pp. 5-16 ◽  
Keyword(s):  
High Pressure ◽  
High Pressures ◽  
Decompression Sickness ◽  
Biological Effects ◽  
Intermolecular Forces ◽  
Inert Gas ◽  
Set Constraints ◽  
Physico Chemical ◽  
Per Se ◽  
Classical Thermodynamics

Physico-chemical principles set constraints on the response of biological systems to high-pressure gases and to pressure per se . They also indicate the mechanisms that may be involved. Classical thermodynamics, intermolecular forces and the theory of solutions and many other areas of physical chemistry have contributed to our understanding of the problems faced by divers breathing gases at high pressure, in particular the high pressure neurological syndrome, inert gas narcosis and decompression sickness. The value and the limitations of physico-chemical arguments when applied to the problems of underwater physiology are analysed.

Origin of Hepatic Nuclear Inclusion Bodies

1973 ◽  
Vol 31 ◽  
pp. 426-427
Author(s):  
F. G. Zaki ◽  
J. A. Greenlee ◽  
C. H. Keysser
Keyword(s):  
Inclusion Bodies ◽  
Storage Disease ◽  
Glycogen Storage ◽  
Nutritional Deficiencies ◽  
Nuclear Inclusion ◽  
Electron Microscopic ◽  
Human Liver Cells ◽  
Microscopic Studies ◽  
Per Se ◽  
Experimental Liver

Nuclear inclusion bodies seen in human liver cells may appear in light microscopy as deposits of fat or glycogen resulting from various diseases such as diabetes, hepatitis, cholestasis or glycogen storage disease. These deposits have been also encountered in experimental liver injury and in our animals subjected to nutritional deficiencies, drug intoxication and hepatocarcinogens. Sometimes these deposits fail to demonstrate the presence of fat or glycogen and show PAS negative reaction. Such deposits are considered as viral products.Electron microscopic studies of these nuclei revealed that such inclusion bodies were not products of the nucleus per se but were mere segments of endoplasmic reticulum trapped inside invaginating nuclei (Fig. 1-3).

Fission Gas Bubbles in Fractured UO2

1968 ◽  
Vol 26 ◽  
pp. 286-287
Author(s):  
O. M. Katz
Keyword(s):  
Electron Microscopy ◽  
Thermal Gradient ◽  
Gas Bubbles ◽  
Inert Gas ◽  
Thermal Gradients ◽  
Fission Gas ◽  
Beam Heating ◽  
Limited Application ◽  
Bubble Characteristics ◽  
Electron Beam Heating

The swelling of irradiated UO2 has been attributed to the migration and agglomeration of fission gas bubbles in a thermal gradient. High temperatures and thermal gradients obtained by electron beam heating simulate reactor behavior and lead to the postulation of swelling mechanisms. Although electron microscopy studies have been reported on UO2, two experimental procedures have limited application of the results: irradiation was achieved either with a stream of inert gas ions without fission or at depletions less than 2 x 1020 fissions/cm3 (∼3/4 at % burnup). This study was not limited either of these conditions and reports on the bubble characteristics observed by transmission and fractographic electron microscopy in high density (96% theoretical) UO2 irradiated between 3.5 and 31.3 x 1020 fissions/cm3 at temperatures below l600°F. Preliminary results from replicas of the as-polished and etched surfaces of these samples were published.

The Eleventh Circuit Holds that Agreements in which Pharmaceutical Companies Pay Generic Companies Not to Compete May be Valid

2004 ◽  
Vol 32 (1) ◽  
pp. 181-184
Author(s):  
Amy Garrigues
Keyword(s):  
Pharmaceutical Companies ◽  
Court Decisions ◽  
Patent Holder ◽  
Trial Court ◽  
Court Of Appeals ◽  
The Us ◽  
Antitrust Laws ◽  
Per Se ◽  
Appeals Court ◽  
Two Sides

On September 15, 2003, the US. Court of Appeals for the Eleventh Circuit held that agreements between pharmaceutical and generic companies not to compete are not per se unlawful if these agreements do not expand the existing exclusionary right of a patent. The Valley DrugCo.v.Geneva Pharmaceuticals decision emphasizes that the nature of a patent gives the patent holder exclusive rights, and if an agreement merely confirms that exclusivity, then it is not per se unlawful. With this holding, the appeals court reversed the decision of the trial court, which held that agreements under which competitors are paid to stay out of the market are per se violations of the antitrust laws. An examination of the Valley Drugtrial and appeals court decisions sheds light on the two sides of an emerging legal debate concerning the validity of pay-not-to-compete agreements, and more broadly, on the appropriate balance between the seemingly competing interests of patent and antitrust laws.

Fusion and Fission Processes in Exocytosis: Possible Roles for Synexin and Osmotic Lysis in the Two Events

1980 ◽  
Vol 38 ◽  
pp. 594-597
Author(s):  
H.B. Pollard ◽  
C.E. Creutz ◽  
C.J. Pazoles ◽  
J.H. Scott
Keyword(s):  
Small Molecules ◽  
Chromaffin Cells ◽  
Adrenal Glands ◽  
General Concept ◽  
Extracellular Calcium ◽  
Large Protein ◽  
Granule Membrane ◽  
Osmotic Lysis ◽  
Per Se ◽  
Chemical Evidence

Exocytosis is a general concept describing secretion of enzymes, hormones and transmitters that are otherwise sequestered in intracellular granules. Chemical evidence for this concept was first gathered from studies on chromaffin cells in perfused adrenal glands, in which it was found that granule contents, including both large protein and small molecules such as adrenaline and ATP, were released together while the granule membrane was retained in the cell. A number of exhaustive reviews of this early work have been published and are summarized in Reference 1. The critical experiments demonstrating the importance of extracellular calcium for exocytosis per se were also first performed in this system (2,3), further indicating the substantial service given by chromaffin cells to those interested in secretory phenomena over the years.

The importance of physical training for preventive care in the elderly

2002 ◽  
Vol 59 (7) ◽  
pp. 323-327
Author(s):  
Baum
Keyword(s):  
Preventive Care ◽  
Körperliche Aktivität ◽  
Physical Training ◽  
Ältere Menschen ◽  
The Elderly ◽  
Per Se

Der mit zunehmendem Alter beobachtbare Verlust an Kraft, Koordination, Ausdauer und Flexibilität ist nur zum Teil als Alterungsprozess per se zu verstehen. Ein wesentlicher Einflussfaktor ist die körperliche Aktivität, d.h. die impliziten oder expliziten Trainingsreize. Denn alle körperlichen Leistungsmerkmale sind noch bis ins höchste Alter unter der Voraussetzung trainierbar, dass die Trainingsintensität und die Reizdichte hinreichend hoch sind. Bei Trainingsangeboten für ältere Menschen kommen der Kraft und der Koordination eine besondere Bedeutung zu, da sie die Basis für eine selbständige Lebensführung darstellen. Um das Krafttraining aus kardio-vaskulärer Sicht möglichst sicher zu gestalten, wurde von uns eine Trainingsform entwickelt und erprobt, bei der es im Gegensatz zu herkömmlichen Methoden zu signifikant geringeren Blutdruckanstiegen kommt.

Hausstaubmilbenallergie

2012 ◽  
Vol 69 (4) ◽  
pp. 249-252 ◽  
Author(s):  
Carrard ◽  
E. Pichler
Keyword(s):  
Per Se

Hausstaubmilben sind kleine Spinnentiere, die weltweit vom gemäßigten bis zum tropischen Klima gefunden werden. Proteine, alle mit enzymatischen Eigenschaften, aus dem Gastrointestinaltrakt und folglich im Hausstaubmilbenkot sind Auslöser von allergischen Erkrankungen, die aufgrund einer kontinuierlichen Exposition von geringen Allergenmengen meist chronisch verlaufen. Klinisch äußert sich dies mit einem schleichenden Krankheitsbeginn: eine chronisch verstopfte Nase und - zu Beginn typischerweise - einem Anstrengungsasthma, das sich bei längerer Dauer verstärkt. Bei Vorliegen einer atopischen Dermatitis kann es auch nach Milbenkontakt zu einer Verstärkung der Dermatitis kommen. Die Anzahl an Hausstaubmilben und die Menge an Milbenallergen hängt von der relativen Luftfeuchtigkeit ab, wobei eine Luftfeuchtigkeit von > 50 %, wie es in sehr gut isolierten Häusern oder durch das Klima per se vorkommt, zu einem guten Gedeihen der Hausstaubmilben führt. Nahrungsquelle der Hausstaubmilben sind Hautschuppen, die ubiquitär in Polstermöbeln, Matratzen und Teppichen vorkommen. Die chronischen, recht unspezifischen und oft allergenunabhängigen Beschwerden verzögern oft die Diagnostik, welche durch eine ausgedehnte Allergieabklärung z. B. mittels Hauttestung erfolgt. Die Therapie besteht in erster Linie aus topischen Kortikosteroiden. Trotz widersprüchlicher Daten und Metaanalysen in der Literatur zur Hausstaubsanierung scheint das allgemein eher trockene Klima im Winter in der Schweiz eine Hausstaubsanierung in den Wohnungen zu begünstigen und wird deshalb auch empfohlen. Eine weitere Therapieoption ist die Durchführung einer spezifischen Immuntherapie mit gutem Erfolg bei Kindern und Erwachsenen. Verbesserungen der Diagnostik und Immuntherapie sind durch Einsatz der rekombinanten Allergene zu erwarten.

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