Search

The great European expansion of the Age of geographical discoveries was the final outcome of an economic, technical and scientific development, begun centuries before. The author briefly examines the evolution of ships up to the carrack and the caravel, which were the protagonists of oceanic voyages, and of sailing techniques, including navigation by the stars which allowed sailors at the end of the 15th century to know the position of the ship even on the open sea. The contribution of scholars is also examined and their noteworthy share in building new instruments and in elaborating scientific theories about the shape of the world and about the distribution of sea and land, upon which great sailors founded those projects, that would lead to the exploration of New Worlds.

In 1989 researchers evaluated the impact of a 3 day course in counseling and interpersonal communication skills for family planning nurses in Ogun State Nigeria on quality of service delivery and on client compliance with follow up appointments. They interviewed 480 clients observed 39 nurses and examined the medical records of 1001 clients who visited the 8 clinics. 97% of clients who spoke to a trained nurse felt the nurse earnestly listened whereas only 66% of those who spoke with an untrained nurse felt this (p

Perfusion of intestinal organs increases in response to acute normovolemic hemodilution (ANH). However, detailed studies on distribution of regional splanchnic organ perfusion during ANH are lacking. We therefore carried out this study to test the hypothesis that ANH does not cause disturbance of physiologic patterns of regional splanchnic organ blood flow. After governmental permission, 22 anesthetized dogs were instrumented to allow invasive hemodynamic measurements and intracardial injection of radioactive microspheres (diameter 15 micro m) for determination of regional organ perfusion. Measurements were made at baseline (hematocrit 37 +/- 3%) and after ANH with 6% hydroxyethyl starch (mol. wt. 200000 / 0.5) to hct 20 +/- 1%. After completion of the protocol, splanchnic organs were removed and dissected into small samples according to anatomical and functional principles. Regional perfusion was determined based on the microsphere content of each sample. Hepatic, intestinal, and pancreatic blood flow increased with ANH. Hepatic arterial blood flow rose by 86%, whereas portal venous perfusion increased by 28%. Small intestine mucosal perfusion was augmented by 68% while the non-mucosal tissue compartment of the gut wall received 32% more blood flow after ANH which is in proportion to the increase in cardiac index after ANH. This redistribution of intestinal flow might be the basis for the preservation of tissue oxygenation during moderate isovolemic anemia.

Hepatorenal perfusion and function were assxssed in 22 dogs undergoing acute normovolemic hemodilution (ANH) to a hematocrit (Hct) of 20% using 6% hydroxyethyl starch (200.000/0.5) as the diluent. Organ perfusion was determined with the radioactive microspheres method. Renal function was assessed by urinary output, creatinine clearance and fractional sodium excretion. Blood volume as well as hepatic function were derived from indocyanine green (ICG) dilution kinetics. Hepatocellular integrity was determined by serum enzymatic activity of glutamate-oxalacetate-transaminase (GOT) and glutamate-pyruvate- transaminase (GPT). ANH to Hct 20% did not change blood volume and mean aortic pressure, while heart rate was slightly elevated (p0.05) by 5 beats per minute and cardiac output increased by 29% (p0.05). In contrast to the liver, where arterial and portal venous blood flow increased (86% and 28%, respectively; p0.05), total renal blood flow as well as intraorgan distribution of renal blood flow remained unchanged post-ANH. While creatinine clearance remained unchanged following ANH, urinary output and fractional urinary excretion increased (p0.05). In response to enhanced hepatic blood flow after ANH, intravascular half-life of ICG was reduced (p0.05) and ICG clearance increased (p0.05). Serum enzymatic activity of GPT decreased upon ANH (p0.05), while GOT activity remained unchanged. ANH to a Hct 20% does not impair hepatorenal function. Increased urinary output points out the necessity for proper adjustment of crystalloid infusion to maintain normal intravascular volume and avoid hypovolemia and the associated risk of tissue hypoxia.

A device (1) for ultrasound tests, comprising one or more transducers (4) for generating ultrasound beams with different powers and/or frequencies to be projected in direction of a plurality of targets (11), guaranteeing the separate control of the temperature both of the targets and of the transducers and it allows performing several tests contemporarily, by optimizing the functionality and the efficiency of the device, at the same time by guaranteeing results comparable therebetween for each test, and to this purpose it comprises: a first supporting structure (3) having at least a closed chamber (7; 23) receiving the body of said one or more transducers (4) and it is isolated from a propagation liquid medium, by leaving exposed each respective vibrating surface in contact with said liquid medium at a prefixed distance from the respective targets (11), the closed chamber containing a thermorefrigerating fluid in contact with the body of said one or more transducers; a second supporting structure (10) for said targets (11); means for refrigerating, through said thermorefrigerating fluid, the body of said one or more transducers (4); and means for keeping the liquid medium, which dampens said targets (11), at a predetermined temperature.