97 research outputs found
Submandibular salivary glands and saliva : an experimental study in male mice on cellular growth
Cells turn over at an enormous rate in man and animals. Man loses
250 g of cells into the intestinal lumen every 24 hours (Leblond and
Walker, 1956). The regulatory mechanisms of cellular proliferation have
been extensively studied (for reviews see: D011ling and Riecken, 1974;
Williamson, 1978a,b). Although many factors are postulated to be of
influence, the exact regulatory mechanism is as yet not fully known
(Lipkin, 1973; Gospodarowicz and Moran, 1976).
Studies of intestinal adaptation are increasingly relevant to
modern surgical practice. First of all because recently developed techniques,
including hyperalimentation, ensure the survival of many patients
with massive enterocolic resections, who would formerly have died from
shortage of functioning small bowel. Secondly because of the increasing
numbers of enteric bypass procedures performed for morbid obesity or
hyperlipidemia. In the third place because different patterns of cell
proliferation may be linked with increasing susceptibilities for cancer
(Cayama et al., 1978).
Factors that seem to play an important role in the regulation of
cellular growth are of humoral, neural and luminal origin. There is
considerable evidence that luminal factors play a dominant role in this
regulation (Li et al., 1979). Of these luminal factors food, pancreaticobiliary
secretions and gastric secretions have been studied most, and
all of these factors seem to have an influence on intestinal adaptation
(Weser et al., 1977; l~illiam
Platelet gel and fibrin sealant reduce allogeneic blood transfusions in total knee arthroplasty
Kinetics of Gag-specific cytotoxic T lymphocyte responses during the clinical course of HIV-1 infection: a longitudinal analysis of rapid progressors and long-term asymptomatics.
Prolonged post-faint hypotension can be reversed by dynamic tension
A severe variant of vasovagal syncope, observed during tilt tests and blood donation has recently been termed “prolonged post-faint hypotension” (PPFH). A 49-year-old male with a life-long history of severe fainting attacks underwent head-up tilt for 20 min, and developed syncope 2 min after nitroglycerine spray. He was unconscious for 40 s and asystolic for 22 s. For the first 2 min of recovery, BP and HR remained low (65/45 mmHg and 40 beats/min) despite passive leg-raising. Blood pressure (and symptoms) only improved following active bilateral leg flexion and extension (“dynamic tension”). During PPFH, when vagal activity is extreme, patients may require central stimulation as well as correction of venous return
Noninvasive cardiac output and blood pressure monitoring cannot replace an invasive monitoring system in critically ill patients
Background: Monitoring of cardiac output and blood pressure are standard procedures in critical care medicine. Traditionally, invasive techniques like pulmonary artery catheter (PAC) and arterial catheters are widely used. Invasiveness bears many risks of deleterious complications. Therefore, a noninvasive reliable cardiac output (CO) and blood pressure monitoring system could improve the safety of cardiac monitoring. The aim of the present study was to compare a noninvasive versus a standard invasive cardiovascular monitoring system.
Methods: Nexfin HD is a continuous noninvasive blood pressure and cardiac output monitor system and is based on the development of the pulsatile unloading of the finger arterial walls using an inflatable finger cuff. During continuous BP measurement CO is calculated. We included 10 patients with standard invasive cardiac monitoring system (pulmonary artery catheter and arterial catheter) comparing invasively obtained data to the data collected noninvasively using the Nexfin HD.
Results: Correlation between mean arterial pressure measured with the standard arterial monitoring system and the Nexfin HD was r2 = 0.67 with a bias of -2 mmHg and two standard deviations of ± 16 mmHg. Correlation between CO derived from PAC and the Nexfin HD was r2 = 0.83 with a bias of 0.23 l/min and two standard deviations of ± 2.1 l/min; the percentage error was 29%.
Conclusion: Although the noninvasive CO measurement appears promising, the noninvasive blood pressure assessment is clearly less reliable than the invasively measured blood pressure. Therefore, according to the present data application of the Nexfin HD monitoring system in the ICU cannot be recommended generally. Whether such a tool might be reliable in certain critically ill patients remains to be determined
Atrioventricular and interventricular delay optimization in cardiac resynchronization therapy: physiological principles and overview of available methods
In this review, the physiological rationale for atrioventricular and interventricular delay optimization of cardiac resynchronization therapy is discussed including the influence of exercise and long-term cardiac resynchronization therapy. The broad spectrum of both invasive and non-invasive optimization methods is reviewed with critical appraisal of the literature. Although the spectrum of both invasive and non-invasive optimization methods is broad, no single method can be recommend for standard practice as large-scale studies using hard endpoints are lacking. Current efforts mainly investigate optimization during resting conditions; however, there is a need to develop automated algorithms to implement dynamic optimization in order to adapt to physiological alterations during exercise and after anatomical remodeling
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