in the present study, the tangrah region located in the vicinity of golestannational park was selected for exploring the changes in the amount of the secondaryessential of hypericin in hypericum perforatum in different highlands of the easterngolestan province. the aerial flowered parts of the herb were collected randomly and inthree replications from four altitudes of 300 m, 600 m, 900 m, and ...

Glaucoma is a progressive optic neuropathy resulting in axonal death and is a leading cause of blindness. Several factors play a role in this progressive cell loss. Hypoxia and oxidative stress are among the risk factors for glaucomatous changes. Tissue stress is also very crucial in glaucoma. This fact is evidenced by stress proteins and heat shock proteins in glaucoma models (Tezel & Wax, 200...

OBJECTIVE The current conflict in Afghanistan is the first major military action in which the United States and other North Atlantic Treaty Organization (NATO) forces have found themselves regularly engaged in combat at high altitudes. However, high altitude warfare is not a new concept in Asia by any means. METHODS This article will offer a short general historical review of high altitude wa...

We quantified the effect of an extended live high-train low (LHTL) simulated altitude exposure followed by a series of training camps at natural moderate altitude on competitive performance in seven elite middle-distance runners (Vo2max 71.4 +/- 3.4 mL.min-1.kg-1, mean +/- SD). Runners spent 44 +/- 7 nights (mean +/- SD) at a simulated altitude of 2846 +/- 32 m, and a further 4 7- to 10-d train...

Anesthesia at high altitude is a challenging task for all anesthesiologists. The high-altitude intensivists are challenged by the human organism in a hypoxic environment, and the true research potentials presented by high altitude, where thebody is subjected to an essentially isolatedhypoxic challenge, are just beginning to be realized. One of the problems when talking about high altitude is th...

This case report describes three separate episodes of isolated ataxia, hallucinations of being accompanied by another person, and bilateral dressing apraxia occurring in a single individual without prior warning signs. These symptoms are attributable to disruption of vestibular processing in the temporoparietal cortex or associated limbic structures. Neurological dysfunction at high altitude is...

The altitude of a graph G is the largest integer k such that for each linear ordering f of its edges, G has a (simple) path P of length k for which f increases along the edge sequence of P . We determine a necessary and sufficient condition for cubic graphs with girth at least five to have altitude three and show that for r 4, r-regular graphs with girth at least five have altitude at least fou...

Altitude hypoxia is often associated with impairment of human reproduction. In this study, hormones and macrophage migration inhibitory factor (MIF, a proinflammatory cytokine with key roles in human reproduction) were determined in seven regularly menstruating, lowlander native women living at sea level participating in 14 days of trekking at moderate and high altitude. Blood and saliva sample...

We have previously demonstrated that acclimatization to high altitude elicits increased sympathetic nerve activity in men. The purpose of this investigation was to determine 1) whether women respond in a similar manner as found previously in men and 2) the extent to which menstrual cycle phase influences this response. Sixteen eumenorrheic women (age, 23.6 +/- 1.2 yr; weight, 56.2 +/- 4. 3 kg) ...

The response elicited by exercise on pulmonary pressure, cardiac output, and arterial oxygen saturation in 35 lifetime residents of high altitude has been studied at high altitude (14,900 feet above sea level), and 22 residents of low altitude have been studied at sea level. A procedure combining cardiac catheterization, arterial cannulation, and spirometry was carried out. The exercise was mod...