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51.
J. Richard Jennings Maurits W. VAN DER Molen Riek J.M. Somsen Cynthia Terezis 《Psychophysiology》1990,27(4):385-395
The influence of inducing motor responses of low and high force at different times in the cardiac cycle was examined. A handgrip response was used which allowed the separation of response initiation from response completion. Based on earlier work, we expected initiation, rather than completion, to initiate poststimulus cardiac acceleration. We also thought that preparation for a high force response might alter preparatory changes of interbeat interval differently from preparation for a low force response. Fifteen college-aged male subjects performed a warned reaction time task in which a visual stimulus signalled a handgrip requiring either a high or a low force to close. NoGo trials in which an inhibit signal was presented occurred on 12% of the trials. Stimuli occurred either on the R-wave of the electrocardiogram or 300 ms later. Reaction speed was varied in different trial blocks by rewarding response times of 200 ms (+/- 50 ms), 300 ms, or 400 ms. Results based on the timing of response initiation were essentially identical to those based on the timing of response completion. High force relative to low force was associated with both earlier response initiation and earlier cardiac acceleration. Force did not alter preparatory cardiac deceleration. Force and response speed did, however, alter the level of heart rate after response occurrence. Thus, response initiation (or an earlier response process) appears to induce a cardiac acceleration whose level is influenced by the speed and force of the motor response. 相似文献
52.
Timothy A. Jennings MD Ng Bernard MD Ann Boguniewicz MD Muzaffar Khan MD Donald Rice MD James Figge MD 《Endocrine pathology》1998,9(4):353-361
Hemorrhagic adrenal pseudocysts are uncommon nonneoplastic lesions that have been reported as secondary to intraparenchymal
hemorrhage or alternatively related to endothelial (vascular) cysts. Ultrastructural and immunohistochemical evidence in support
of the latter has been presented, but the exact nature of hemorrhagic adrenal pseudocysts remains poorly defined. We evaluated
six surgical specimens of hemorrhagic adrenal pseudocysts using immunohistochemical staining for CD31 and CD34, as well as
conventional histochemistry. All six cases had hemorrhagic contents within a wall of variable thickness possessing focal areas
of linear, disrupted elastin, and smooth muscle. Three cases demonstrated extensive thrombosis with organization, including
papillary endothelial hyperplasia, simulating angiosarcoma. In these cases, CD31 and CD34 staining decorated areas of papillary
endothelial hyperplasia as well as foci of the internal cyst lining, whereas the other cases were negative for both antibodies.
Of interest is the history of FNA prior to surgical resection in three cases of hemorrhagic adrenal pseudocysts, two of which
showed papillary endothelial hyperplasia. The presence of papillary endothelial hyperplasia and our immunohistochemical findings
support, the conclusion that adrenal pseudocysts are posthemorrhagic and derive from vascular disruption. Furthermore, FNA
or other interventional studies may be associated with papillary endothelial hyperplasia in hemorrhagic adrenal pseudocysts. 相似文献
53.
Overflow of catecholamine neurotransmitters to the circulation: source, fate, and functions 总被引:27,自引:0,他引:27
M Esler G Jennings G Lambert I Meredith M Horne G Eisenhofer 《Physiological reviews》1990,70(4):963-985
54.
Publication Guidelines for Heart Rate Studies in Man 总被引:1,自引:0,他引:1
J. Richard Jennings W. Keith Bberg J. Stanford Hutcheson Paul Obrist Stephen Porges Graham Turpin 《Psychophysiology》1981,18(3):226-231
Publication guidelines are provided for the collection, quantification, and analysis of heart rate data. 相似文献
55.
L. J. Jennings G. M. Salido M. -J. Pozo J. S. Davison K. A. Sharkey R. W. Lea J. Singh 《Inflammation research》1995,44(10):447-453
We have investigated the effects of histamine on motility of the gallbladder and characterized the receptor types involved. Histamine and the histamine H1-receptor agonist, 2-thiazolylethylamine (2-TEA) contracted the isolated guinea-pig gallbladder strip in a dose dependent manner. The contractile response to histamine was shifted to the right by the H1-receptor antagonist, mepyramine. In pre-contracted gallbladder strips, the H2-receptor agonist dimaprit reduced the tension generated in a dose dependent fashion. The histamine H2-receptor antagonist, ranitidine shifted the histamine concentration effect curve to the left and attenuated the dose dependent relaxations elicited at high concentrations. The histamine H3-receptor agonist, (R)--methylhistamine (RMHA) elicited dose dependent contraction of the tissue which was significantly inhibited in the presence of mepyramine. The effects of electrical field stimulation (EFS) on the strips were not significantly altered by the presence of RMHA (10–10–10–7 M) indicating little pre-synaptic H3 activity in this tissue. Histamine immunoreactivity (IR) was detected in gallbladder whole mount preparations of the mucosa and the muscularis/serosa. The histamine IR appeared cell bound in cells of varying morphological characteristics but no IR was detected in nerve fibres or cell bodies (ganglia). Alcian blue staining was consistent with the distribution of histamine IR cells as mast cells. The results indicate that histamine is distributed in the guinea-pig gallbladder and it can regulate contractile activity via activation of H1 and H2 but not H3 receptors. 相似文献
56.
The replication of type A influenza viruses in the infant rat: a marker for virus attenuation 总被引:1,自引:0,他引:1
Twenty recombinant influenza virus strains bearing HSw1N1, H1N1 or H3N2 surface antigens, together with their respective wild-type or laboratory-propagated parent viruses, were inoculated into 2 day-old infant rats and their replication in the turbinates and lungs of these animals observed over a period of 5 days. In addition, the ability of each of the recombinant and parent viruses to enhance a subsequent infection of these infant rats by Haemophilus influenzae type b was determined. The results showed that both parent and recombinant viruses replicated less well in the lungs than in the turbinates of infant rats, but the titres in both tissues were generally lower for the recombinant strains. The capacity of the majority of the recombinant influenza viruses to promote bacterial infection of the infant rats, as determined by the incidence of H. influenzae bacteraemia and meningitis, was also markedly less than that of their parent viruses. A correlation between virulence for man and both the replication in infant rat turbinates and the ability to enhance H. influenzae infection, was established for the virus strains studied. The data are discussed in relationship to the value of the infant r-H influenzae system as a laboratory marker for the determination of the virulence of influenza virus strains. 相似文献
57.
Species identification of invasive aspergillosis in man 总被引:1,自引:0,他引:1
58.
A graded dose assessment of the efficacy of beclomethasone dipropionate aerosol for severe chronic asthma. 总被引:7,自引:0,他引:7
J H Toogood N M Lefcoe D S Haines B Jennings N Errington L Baksh L Chuang 《The Journal of allergy and clinical immunology》1977,59(4):298-308
In a 26-wk double-blind controlled study of 34 patients whose asthma had been poorly controlled despite oral steroids, valuable clinical and pulmonary function improvement was derived by adding beclomethasone aerosol to the prednisone regimen. The amount of improvement correlated linearly with beclomethasone dosage over the range 200 to 1,600 microng/day. These patients required relatively high dosage. Success in achieving asymptomatic status was only 26% with the conventional 400 microng/day and 60% at 1,600 microng/day. Oropharyngeal candidiasis was also dose-related but did not prohibit the use of high-dosage beclomethasone. Respiratory infections, physical signs, blood glucose, and electrolytes were unaffected by the drug. A dose-related suppression of cortisol secretion was demonstrated, but about 1/4 of the group had normal plasma cortisol even at 1,600 microng/day plus the oral prednisone. An individualized risk-benefit assessment seems a better basis for choosing an optimal beclomethasone regimen for each patient than adherence to a conventionalized fixed dosage of 400 microng/day. This requires definition of: (1) a specific goal of treatment in the individual patient and the beclomethasone dosage required to achieve it; (2) the adrenocortical functional response of that particular patient to the desired dose of beclomethasone; and (3) the presence and degree of any dose-limiting constraints such as preexisting complications of steroid use. 相似文献
59.
Comparison of the sensitivities of the version 1.5 and version 1.0 ultrasensitive Roche AMPLICOR HIV-1 MONITOR kits at low concentrations of human immunodeficiency virus RNA
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Brambilla DJ Jennings C Morack R Granger S Bremer JW 《Journal of clinical microbiology》2004,42(6):2819-2820
The sensitivities of the version 1.5 and 1.0 Roche UltraSensitive AMPLICOR HIV-1 MONITOR tests were compared using panels of coded samples of subtype B human immunodeficiency virus type 1 spiked into plasma at predetermined concentrations. Results indicate that the version 1.5 kit is more sensitive than the version 1.0 kit. 相似文献
60.
C C Hoch C F Reynolds J R Jennings T H Monk D J Buysse M A Machen D J Kupfer 《Neurobiology of aging》1992,13(2):353-356
This study investigated the relationship of daytime sleepiness and performance on a vigilance test in a sample of 10 healthy men and 13 women in their 80s (mean age 83.0 +/- 3.1 years) and 18 men and 12 women in their 20s (25.0 +/- 3.1). We hypothesized that "successfully" aged healthy individuals would have more daytime sleepiness with differentially greater decrements in performance than a younger comparison group. Daytime sleepiness was measured physiologically by the Multiple Sleep Latency Test (MSLT) and through self-report by the Stanford Sleepiness Scale (SSS). Morning and evening performance was measured with the Mackworth Clock Test of vigilance. The major findings were the absence of correlation between either MSLT or SSS daytime sleepiness with performance measures, no difference in daytime sleepiness between the old and young groups and performance decrements among the healthy elderly on all parameters. Results suggest that the modest decrements in performance among the elderly cannot be attributed to daytime sleepiness. 相似文献