摘要:

To investigate the possibility that salt-sensitive hypertensives have deficient sodium excretion, the sodium retained by 20 hypertensive patients during a salt load (SL = 3.88 mEq/Kg/day) was calculated for 3 days immediately after 4 days of sodium deprivation (SD = 9 mEq/d). Patients were divided into two groups by arterial pressure responses to SD: responders (N = 10) whose pressures became normal rapidly and averaged <140/90 during SD and nonresponders (n = 10) whose pressures were not affected. Sodium retention (mEq/Kg) during SL was calculated as cumulative sodium intake minus cumulative urinary sodium divided by body weight. Responders retained more sodium during SL than nonresponders (3.71 · 0.96 [SD] vs. 2.52 · 1.05 mEq/Kg, p <0.02). This could not be explained by a measurable decrease in filtered sodium load since creatinine clearance was the same in each group. Neither was it associated with differences in plasma renin activity (PRA) or aldosterone excretion rates (AER). Whereas PRA was significantly lower in responders at the end of SD, AER was not different; with SL, group values were equally suppressed. Also sodium excretion was not correlated with arterial pressure except in nonresponders on the last day of SL. These data indicate that salt-sensitive hypertensives handle sodium differently than nonsalt-sensitive hypertensives.

ISSN:0002-9629    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

Cholesterol saturated bile and gallbladder stasis are important factors in the pathogenesis of cholesterol gallstones. The degree to which either or both of these factors affect gallbladder transport of fluid remains obscure. The authors tested the hypothesis that both cholesterol saturated bile and gallbladder stasis, and not stasis alone, promotes gallbladder fluid absorption. Prairie dogs were maintained for 2 weeks on either a control chow, total parenteral nutrition (TPN), or a 1.2% cholesterol enriched chow. The bile acid pool was labeled with14C-cholic acid and indexes for cholesterol saturation (CSI) and gallbladder stasis (Rsa) were determined. Fluid transport was indirectly measured by calculating the ratio of gallbladder to hepatic bile concentrations of individual and total biliary lipids. Despite evidence of stasis in prairie dogs maintained on TPN, bile was unsaturated, and gallbladder absorption was not appreciably changed. In contrast, cholesterol-fed animals had cholesterol supersaturated bile, gallbladder stasis, and altered gallbladder absorption, as manifested by a significant change in the ratio of gallbladder to hepatic bile concentrations of individual and total biliary lipids. These data suggest that both cholesterol saturated bile and gallbladder stasis, and not stasis alone, are essential in promoting the enhanced gallbladder absorption, which has previously been observed during early cholesterol gallstone formation.

ISSN:0002-9629    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

Rats were treated with subcutaneous benzene, 440 mg/kg, for 3 and 14 days (acute and chronic exposure). Their hepatic cell heme and drug metabolizing enzymes as well as cell morphology by electron microscopy were examined. Electron micrographs of hepatocytes from the benzene-treated rats showed disruption of the mitochondrial membranes and mitochondrial structure. The activity of the rate-limiting enzyme of heme synthesis, δ-aminolevulinic acid synthase was increased 1.5–2-fold in both acutely and chronically exposed animals. In the acutely exposed animals, there was a 50% inhibition of the second enzyme of heme synthesis, δ-aminolevulinic acid dehydratase, while in the chronically exposed there was 70% inhibition. The rate-limiting enzyme of heme degradation, heme oxygenase, was increased more than twofold in both sets of animals. Cytochrome P-450 content was increased 77% in the acutely treated and 35% in the chronic. Associated with this increase in cytochrome P-450 content, there was a twofold increase in both arylhydrocarbon hydroxylase and aminopyrine-N-demethylase activities after acute exposure. During chronic exposure, however, there was a return to normal of the aminopyrine-N-demethylase activity and a decline in arylhydrocarbon hydroxylase induction to 1.25 times control. Results from this study indicate that benzene exposure produces adverse effects on mitochondria and heme metabolism. The precise relationships of these disturbances to benzene toxicity are not clear; however the possible role of heme oxygenase and degree of cytochrome P-450 induction are considered. Finally, the alterations of arylhydrocarbon hydroxylase and aminopyrine-N-demethylase activities point to a potential mechanism of differential toxicity from metabolites of benzene.

ISSN:0002-9629    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

Blood groups of 137 patients with acute pyelonephritis and chronic upper tract infection, cystitis, and asymptomatic bacteriuria were compared with those of a normal uninfected control population. In addition, the identified uropathogens were categorized according to the patient's blood group. There was a significant association between the diagnosis of chronic upper tract infection and blood group B as compared with controls (p = <0.05, χ2). Analysis of the bacterial isolates showed that more patients with blood group B had infections withPseudomonas sp., Klebsiella pneumoniae, andProteussp. than was expected; and fewer patients with blood group A had infections withPsuedomonasthan predicted (p = <0.05, χ2). There was an increased number of patients in blood group AB with infections caused byEscherichia coliandKlebsiella pneumoniae.These results suggest that an individual's blood group may be a significant factor in the host–response to bacterial invasion and influence the development of infection with certain gram-negative bacilli.

ISSN:0002-9629    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

To compare high frequency positive pressure ventilation (HFV) to conventional ventilation (CV) in experimental meconium aspiration syndrome (MAS) adult rabbits were randomly assigned to one of four groups: sham (G1) n = 10, control (G2) n = 12, CV (G3) n = 6, and HFV (G4) n = 6. All animals were stabilized on an F1O2of 0.70 after a tracheostomy and arterial line were placed. The alveolar-arterial oxygen difference (A-aDO2) was calculated for each blood gas measurement and mean airway pressure (MAP) measured in CV and HFV at the time of each blood gas. Human meconium (2 ml/kg of 25% solution) was instilled intratracheally (MI) in groups 2–4. Group 3 was then placed on conventional ventilation with a rate of 40 BPM while Group 4 with a rate of 400 BPM. Analysis of variance was used to compare A-aDO2and MAP. There was no significant difference between group 4 and group 2, while there was a significant difference between group 3 and groups 2 and 4. Sustained inflation of 25 cm H2O as used for 20 seconds was used before HFV in a fifth group (n = 6) that was added to the study and was otherwise identical to HFV. There was no significant difference between this fifth group and group 2 or group 4. Our findings indicate HFV is not efficacious in experimental MAS whether or not sustained inflation is used.

ISSN:0002-9629    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

In recent years, increasing clinical and experimental data have provided compelling evidence that neutrophil-derived oxygen radicals and their metabolites are important mediators of vascular endothelial injury. In this review, attention is directed toward in vitro, ex vivo, and in vivo experimental studies contributing to current understanding of mechanisms of oxyradical mediated endothelial damage. Although these studies may have broad significance, they appear to have particular relevance to the pathogenesis of the adult respiratory distress syndrome and other types of acute pulmonary dysfunction.

ISSN:0002-9629    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

Q fever endocarditis, which is seen most often in Great Britain and Australia, has been rarely observed in the United States. A patient with an eight month febrile illness who had signs and symptoms of endocarditis and serologic studies diagnostic of Q fever endocarditis is reported. A history of extensive travel makes it unclear where he originally contracted the disease. Q fever endocarditis is probably underdiagnosed and should be looked for in any case of culture negative endocarditis or chronic fever of unknown origin.

ISSN:0002-9629    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

A previously healthy 61-year-old woman was seen with an abnormal chest roentgenogram and a 3-week history of fever, chills, malaise, and right upper quadrant pain. Blood cultures revealedPasteurella multocidasensitive to penicillin. Liver spleen radioisotope scan and CT scan revealed space occupying lesions in the right lobe of the liver. The patient was a gardener with no pets or animal exposure. This case illustratesP. multocidasepticemia and a liver abscess in a patient without animal exposure. In addition, the possibility of soil as another reservoir of infection is raised.

ISSN:0002-9629    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

Endocarditis due to Haemophilus is uncommon. This is the first reported case caused byHaemophilus aegyptius. The course of the disease was complicated by pericarditis, congestive heart failure, and myocardial abscess formation. Surgical removal of the damaged aortic valve was not beneficial. The biologic properties of the organism included urea degradation, absence of indole metabolism, and absence of the enzyme ornithine decarboxylase.

ISSN:0002-9629    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

Pharmacologic intervention aimed at altering the natural history of acute renal failure is a routine practice without scientific support of efficacy. Oliguria has become a separate disease entity with an apparent disregard for the underlying condition that caused it Volume expansion is clearly beneficial in preventing many volume depleted patients from progressing to acute renal failure. While mannitol and furosemide have been used to “convert” oliguric acute renal failure to the more easy to manage non-oliguric acute renal failure, published reports suggest that responders were not as ill as non-responders. The use of dopamine to increase urine flow in patients with established acute renal failure is the current fashion, but there is little evidence that this drug raises the glomerular filtration rate or shortens the course of acute renal failure. These pharmacologic therapies increase the complexity and cost of care with little tangible evidence of benefit to the patient or the physician caring for the patient.

ISSN:0002-9629    

出版商:OVID    

年代:1986

数据来源: OVID