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T N Nguyen

Publications and source records attributed to T N Nguyen.

98 records · Page 6Linked to original sources

Effects of magnesium chloride on cardiovascular hemodynamics in the neurally intact dog.

To assess the cardiovascular actions of magnesium in neurally intact animals, magnesium chloride (1-4 mM/min) administered i.v., producing a peak arterial magnesium level between 4.7 and 7.2 mg/dl, was given to alpha-chloralose-anesthetized, open-chest dogs. Magnesium lowered heart rate by 36 +/- 11 beats/min (P less than .05), cardiac output by 0.7 +/- 0.2 liters/min (P less than .05), left ventricular (LV) peak dP/dt by 410 +/- 96 mm Hg/sec (P less than .05) and aortic and pulmonary artery pressures, but it did not change LV end-diastolic pressure, systemic resistance or pulmonary resistance. Coronary blood flow also decreased by 39 +/- 11% (P less than .05), myocardial oxygen consumption by 88 +/- 22% (P less than .05) and myocardial oxygen extraction by 53 +/- 16% (P less than .05). When heart rate was held constant, magnesium still decreased LV systolic pressure, LV peak dP/dt and coronary blood flow. The increase in serum magnesium was accompanied by an increase in serum calcium (by 1.4 +/- 0.2 mg/dl; P less than .05) and a fall in serum potassium (by 0.21 +/- 0.1 mEq/l), but not by a change in serum sodium, myocardial electrolyte arteriovenous differences or arterial pH. Thus, at blood concentrations that are observed in humans after therapeutic dosages of magnesium, a depression of cardiac performance is observed in the anesthetized dog. Although magnesium produces a fall in coronary blood flow, this appears to be due at least in part to a decrease in myocardial oxygen requirements because myocardial oxygen extraction also decreases. Rapid changes in serum electrolytes accompany these hemodynamic effects.

Animals↗

Blood coagulation monitoring and anticoagulant therapy after liver resection: brief report.

In this sample of 140 patients undergoing hepatic resection to remove cancerous tissue, hypercoagulation was the most common postoperative BCD; in ten patients, this complication led to hepatic failure and hepatic coma. These findings differ from those previously reported in the literature, possibly because our patients had advanced hepatomas which had already infiltrated the great vessels of the liver, and/or the remaining liver was seriously cirrhotic. We found that blood-coagulation monitoring and anticoagulation therapy yielded encouraging results, and it is our hope that this treatment in combination with immunotherapy will prolong the survival of these patients.

Adolescent↗

[Diagnosis and surgical treatment of intraocular cysticercosis (author's transl)].

Operative treatment was employed in 19 cases of intraocular cysticercosis: 6 subretinal (3 in the macular region) and 13 intravitreal (3 mobile, 10 fixed). The essential diagnostic sign is the appearance of the parasitic vesicle (iridescent tint, movements of the wall and the scolex), but difficulties may arise because of severe intraocular lesions : vitreous clouding, chorioretinitis, detachment of the retina. The site of the vesicle must be determined before and during operation. Fixed cysticerci require that the globe be opened by a well-placed incision. If they are mobile, they can be aspirated through the pars plana with the erysiphake or a trocar, depending on the size of the vesicles. Aspiration is also necessary when there is total detachment of the retina of a fixed intravitreal vesicle, after freeing adhesions. Successful results were obtained in 15 of the 19 cases treated.

Cysticercosis↗

Agent orange and the risk of gestational trophoblastic disease in Vietnam.

There have been claims of an increased risk for gestational trophoblastic disease (i.e., hydatidiform mole and choriocarcinoma) in Vietnam since the period of Agent Orange sprayings. In 1990, we conducted a case-control study in Ho Chi Minh City to investigate risk factors for gestational trophoblastic disease in Vietnam. Eighty-seven married women, all of whom had a recent pathologic diagnosis of gestational trophoblastic disease, identified in the Obstetrical and Gynecological Hospital, were included in the study. Eighty-seven married women who were admitted mainly in the surgery departments of the same hospital were the controls, and they were matched to cases for age and area of residence. Odds ratios (ORs), adjusted for matching variables and other potential confounders, were estimated with unconditional logistic regression. A statistically significant trend in risk was observed with previous live births (p = .01). Cases were found to eat less meat per wk (OR = 0.4, 95% confidence interval [95% CI] = 0.2-0.9 for > or = five meat dishes) and to own fewer consumer goods than controls. An increase in risk was associated with the breeding of pigs (OR = 5.7, 95% CI = 1.2-27.6 for raising three or more pigs). A cumulative Agent Orange exposure index was constructed, using the patient's complete residence history. No significant difference was found between cases and controls for this index (OR = 0.7, 95% CI = 0.2-1.8 for high-exposure category), nor was such a difference noted for the agricultural use of pesticides.

2,4,5-Trichlorophenoxyacetic Acid↗