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21.
Comparative plasma catecholamine and hemodynamic responses to handgrip, cold pressor and supine bicycle exercise testing in normal subjects 总被引:2,自引:0,他引:2
J R Stratton J B Halter A P Hallstrom J H Caldwell J L Ritchie 《Journal of the American College of Cardiology》1983,2(1):93-104
Serial hemodynamic and plasma catecholamine responses were compared among 10 healthy men (27 +/- 3 years) (+/- 1 standard deviation) during symptom-limited handgrip (33% maximal voluntary contraction for 4.4 +/- 1.8 minutes), cold pressor testing (6 minutes) and symptom-limited supine bicycle exercise (22 +/- 5 minutes). Plasma catecholamine concentrations were measured by radioenzymatic assays: ejection fraction and changes in cardiac volumes were assessed by equilibrium radionuclide angiography. During maximal supine exercise, plasma norepinephrine and epinephrine concentrations increased three to six times more than during either symptom-limited handgrip or cold pressor testing. Additionally, increases in heart rate, systolic blood pressure, rate-pressure product, stroke volume, ejection fraction and cardiac output were significantly greater during bicycle exercise than during the other two tests. A decrease in ejection fraction of 0.05 units or more was common in young normal subjects during the first 2 minutes of cold pressor testing (6 of 10 subjects) or at symptom-limited handgrip (3 of 10), but never occurred during maximal supine bicycle exercise. The magnitude of hemodynamic changes with maximal supine bicycle exercise was greater, more consistent and associated with much higher sympathetic nervous system activation, making this a potentially more useful diagnostic stress than either handgrip exercise or cold pressor testing. 相似文献
22.
In an informative qualitative study 75 U (near the range of 1 U/kg) secretin given as a snuff resulted in a weak but significant stimulation of pancreatic bicarbonate output in 8 volunteers studied. The result further indicated that this dose would slightly inhibit pentagastrin-stimulated gastric acid secretion. This was confirmed in a quantitative study at the dose of 150 U (similar to 2 U/kg), and the mean amount of inhibition of MAO was 30% in the 10 subjects studied. A supramaximal dose of 1 mg (approximatively 54 U/kg) of synthetic secretin given to one volunteer resulted in a transient block of near maximally pentagastrin-stimulated gastric acid secretion. The amount of acid inhibition as compared to a control experiment was 45% in the first and 52% in the two post-secretin hours. These results indicate that secretin given as a snuff at dose levels that would induce maximal pancreatic secretion when given as an i.v. injection results only in a weak inhibition of stimulated gastric acid secretion and evokes only a little stimulation of pancreatic bicarbonate secretion. Supramaximal secretin snuff doses have, however, a potent effect on both gastric and pancreatic secretion that is of similar order to that achieved by intravenous secretin. Owing to the obviously incomplete absorption of secretin through the nasal mucosa, secretin snuff is unlikely to solve the therapeutic problem of duodenal ulcer disease. If, however, an active fragment of the peptide could be synthetized at a reasonable price, the greater convenience of pernasal application might compensate for the partial loss of action. 相似文献
23.
Hogikyan RV Wald JJ Feldman EL Greene DA Halter JB Supiano MA 《Metabolism: clinical and experimental》1999,48(4):495-500
Several lines of evidence support peripheral nerve ischemia as a contributing factor in the etiology of human diabetic neuropathy. We questioned whether diabetic subjects with relatively normal nerve function in the baseline state would be more likely than healthy control subjects to show either improvement of ulnar nerve function with acute intraarterial infusion of nitroprusside (vasodilation) or be more sensitive than control subjects to worsening of nerve function with acute intraarterial infusion of norepinephrine (vasoconstriction). We measured forearm blood flow (FABF) using venous occlusion plethysmography and assessed ulnar nerve function at baseline and during two intrabrachial artery infusions. Six nondiabetic control subjects (mean age, 56 years) and 11 subjects with type 2 diabetes (mean age, 58 years) in good general health participated. Only three type 2 diabetic subjects had peripheral sensory neuropathy, which was mild. Among control subjects, there was no significant change in sensory distal latency, motor distal latency, motor proximal latency, or sensory or motor conduction velocity during norepinephrine infusion. In contrast, among type 2 diabetic subjects, there was a significant increase in sensory (baseline vnorepinephrine, 2.73+/-0.10 v 2.94+/-0.10 milliseconds [MS], P< or =.01) and motor distal latencies (baseline v norepinephrine, 2.90+/-0.06 v 3.18+/-0.1 ms, P< or =.001) and motor proximal latency (baseline v norepinephrine, 7.15+/-0.18 v 7.60+/-0.23 ms, P<.01) and a decrease in sensory conduction velocity (baseline v norepinephrine, 52.1+/-2.0 v 47.7+/-1.6 m/s, P<.01) during norepinephrine infusion. There were no consistent changes in nerve function during nitroprusside infusion in either group. In summary, we found that subjects with type 2 diabetes, but not control subjects, demonstrate a decrement in nerve function with vasoconstriction during intraarterial infusion of norepinephrine, but no consistent change during nitroprusside-induced vasodilation. These findings suggest there may be enhanced sensitivity of nerve function to ischemia in type 2 diabetic subjects with mild or absent clinical neuropathy. 相似文献
24.
Coakley G; Mok CC; Hajeer AH; Ollier WE; Turner D; Sinnott PJ; Hutchinson IV; Panayi GS; Lanchbury JS 《Rheumatology (Oxford, England)》1998,37(9):988-991
OBJECTIVE: To examine whether promoter polymorphisms associated with
variation in interleukin-10 (IL-10) production are relevant to the
development of rheumatoid arthritis (RA) or Felty's syndrome (FS). METHODS:
DNA was obtained from 44 FS patients, 117 RA patients and 295 controls. The
promoter region between -533 and - 1120 was amplified by polymerase chain
reaction, and polymorphisms detected by restriction enzyme digest or
sequence-specific oligonucleotide probing. RESULTS: We found no significant
difference in allele or haplotype frequencies between the groups.
CONCLUSION: There is no association between FS or RA and these recently
identified IL-10 promoter polymorphisms. Other genetic or environmental
factors could explain the alterations in IL-10 levels seen in these
conditions.
相似文献
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27.
Prof Fred Halter M.D. Adrian Schmassmann M.D. Andrzej Tarnawski M.D. 《Digestive diseases and sciences》1995,40(11):2481-2486
Grant support: Swiss National Science Foundation (grant 32-26478.89). 相似文献
28.
Diem‐Lan Vu Julie‐Anne Dayer Stavroula Masouridi‐Levrat Christophe Combescure Elsa Boely Nina Khanna Nicolas J. Mueller Martina Kleber Michael Medinger JOERG Halter Jakob Passweg Antonia M. Müller Urs Schanz Yves Chalandon Dionysios Neofytos Christian van Delden Laurent Kaiser 《Transplant infectious disease》2020,22(4)
29.
M. Sue Kirkman MD Vanessa Jones Briscoe PhD NP CDE Nathaniel Clark MD MS RD Hermes Florez MD MPH PhD Linda B. Haas PHC RN CDE Jeffrey B. Halter MD Elbert S. Huang MD MPH Mary T. Korytkowski MD Medha N. Munshi MD Peggy Soule Odegard BS PharmD CDE Richard E. Pratley MD Carrie S. Swift MS RD BC‐ADM CDE 《Journal of the American Geriatrics Society》2012,60(12):2342-2356
30.
CC Thorn M Smith O Aziz TC Holme 《Annals of the Royal College of Surgeons of England》2013,95(1):52-56