We have previously demonstrated that inactivation of the Krox20 gene led to the disappearance of its segmental expression territories in the hindbrain, the rhombomeres (r) 3 and 5. We now performed a detailed analysis of the fate of prospective r3 and r5 cells in Krox20 mutant embryos. Genetic fate mapping indicates that at least some of these cells persist in the absence of a functional Krox20...

the majority of iran’s area is covered by arid and semiarid climates. in these areas, wind causes more erosion compared to water. therefore, determination of wind characteristics especially its velocity is very important. one of the simplest methods that can supply researchers with the origin of wind erosion in the shortest time is synthesizing sand rose model and interpretation of aerial photo...

The separate effects of volume expansion and of increased delivery of sodium on sodium reabsorption in the diluting segment of the distal nephron were studied in man. In six normal subjects during a sustained water diuresis, sodium delivery to the distal nephron was increased without volume expansion by the administration of acetazolamide. In these subjects, free water clearance rose linearly a...

Blood pressure, plasma arginine vasopressin (AVP), and renal excretory responses to short-term water loading (oral load of 20 ml/kg body weight over 30-45 minutes) were compared in 10 normotensive and 13 mild to moderately essential hypertensive subjects. In addition, we examined the renal concentrating ability of an additional group of 10 normotensive subjects and 12 hypertensive subjects in r...

PURPOSE Water homeostasis and transport play important roles in brain function (e.g., ion homeostasis, neuronal excitability, cell volume regulation, etc.). However, specific mechanisms of water transport across cell membranes in neuronal tissue have not been completely elaborated. METHODS The kinetics of transcytolemmal water exchange were measured in neuronal tissue using simultaneous, real...

Means have been described for the study of pressure conditions in normal and pathological skin of living human beings and mice. The true pressure in normal skin cannot be measured directly by any of the means hitherto described, because there is insufficient free fluid to make manometric determinations. However, for practical purposes, the intracutaneous pressure has been approximately estimate...

The majority of Iran’s area is covered by arid and semiarid climates. In these areas, wind causes more erosion compared to water. Therefore, determination of wind characteristics especially its velocity is very important. One of the simplest methods that can supply researchers with the origin of wind erosion in the shortest time is synthesizing sand rose model and interpretation of aerial photo...

Spectroscopic measurements have been made of the nitric oxide and water vapor concentrations in the stratosphere at an altitude of 28 kilometers. The measurements, carried out in situ with the use of a spin flip Raman laser, represent the first accurate determination of nitric oxide as a function of time (as the sun rose) from about 6: 30 to 14: 00 C. D. T.