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81.
82.
Abstract: The main aim of the present investigation was to study systematically the passive and stimulation-evoked release of 3H-5-hydroxytryptamine (3H-5-HT) from rabbit isolated aorta. This was accomplished by preloading rings of aorta with 3H-5-HT (10–6M) and then monitoring by fractional collection the basal 3H-outflow and stimulation-evoked 3H-overflow. The basal 3H-outflow from aorta preloaded with 10–6M of either 3H-5-HT or (-)-3H-noradrenaline (3H-NA) leveled off about 100 min. after the onset of wash-out and remained almost constant thereafter (100–240 min.). The basal 3H-outflow from tissue preloaded with 3H-5-HT was almost 3-fold higher (70–240 min.) than that seen after preloading with 3H-NA. Cocaine (3x10–5M) did not alter the basal 3H-outflow (15–240 min.) from tissue preloaded with 3H-5-HT, while pargyline (5X10–4M) decreased it by about 66% (100–240 min.). Electrical-field stimulation (S1S7, 200 mA, 600 pulses, 0.5 msec, 3 Hz) were applied to the tissue. The initial stimulation-evoked 3H-overflow from aorta preloaded with 3H-5-HT was higher than the subsequent ones (S1-S7: 100, 35, 35, 35, 35, 37, and 40%). Similar results to these were obtained with tissues preloaded with 3H-NA. The stimulation (S1-S7; 200 mA; 600 pulses, 0.5 msec, 3 Hz)-evoked 3H-overflow increased in an apparent linear manner with the amount of current used (50–200 mA). This was also the case for number of pulses (100–900) in the stimulus. The stimulation-evoked 3H-overflow depended in part on the stimulation frequency: unchanged at 2–4 Hz; small increase at 8 Hz; and a 15-fold increase at 16 Hz relative to 2 Hz. Tetrodotoxin (10–6M) decreased the stimulation-evoked 3H-overflow from aorta preloaded with 3H-5-HT (S2-S6) by about 60%, while S1 was not affected. The inhibitory effect of tetrodotoxin was fully reversed by washing the aorta with drug-free salt solution. Omission of Ca2+ from the salt solution reduced the stimulation 3H-overflow by 47–57% (S2-S6) while S1 was unaffected. 6-Hydroxydopamine markedly increased the stimulation-evoked 3H-overflow from 3H-5-HT preloaded rings (180–323% of control). Pargyline (5x10–4M), cocaine (3x10–5M) and removal of endothelium did not alter the stimulation-evoked 3H-overflow evoked by stimulation (S1-S6) of aorta preloaded with 3H-5-HT. It is concluded that 3H-5-HT can be released by electrical-field stimulation as a “false transmitter'’from rabbit isolated aorta. Most of the release is probably of neuronal origin. However, some of the stimulation-evoked 3H-overflow is derived from extraneuronal sites. 相似文献
83.
A randomized controlled trial of electromagnetic therapy in the primary care management of venous leg ulceration 总被引:1,自引:1,他引:0
OBJECTIVE: The aim was to establish the potential efficacy, tolerabilityand side-effect profile of electromagnetic therapy as an adjunctto conventional dressings in the treatment of venous leg ulcers. METHOD: A prospective, randomized, double blind controlled clinicaltrial was carried out in a dedicated leg ulcer clinic basedin one urban general practice. Nineteen patients with leg ulcersof confirmed venous aetiology were assessed. The main outcomemeasures were rate and scale of venous leg ulcer healing, changesin patient-reported pain levels, quality of life, degree ofmobility, side effect profile and acceptability to patientsand staff. RESULTS: Sixty-eight per cent of patients attending this dedicated clinicachieved improvements in the size of their ulcer (4, 21%, healedfully) and in reduced pain levels (P < 0.05) during the trial,despite the chronicity of ulcer histories. Patients treatedwith electromagnetic therapy at 800 Hz were found at day 50to have significantly greater healing (P < 0.05) and paincontrol (P < 0.05) than placebo therapy or treatment with600 Hz. All patients reported improved mobility at the end ofthe study. The electromagnetic therapy was well tolerated bypatients, with no differences between groups in reporting adverseevents, and proved acceptable to staff. CONCLUSION: Despite the small numbers in this pilot study, electromagnetictherapy provided significant gains in the healing of venousleg ulcers and reduction in pain. Keywords. Electromagnetic therapy, RCT, leg ulcers, primary care. 相似文献
84.
123I-MIBG myocardial scintigraphy as a noninvasive screen for the diagnosis of coronary artery spasm
Jong-Won Ha Jong-Doo Lee Yangsoo Jang Namsik Chung June Kwan Se-Joong Rim Young-Joon Lee Won-Heum Shim Seung-Yun Cho Sung-Soon Kim 《Journal of nuclear cardiology》1998,5(6):591-597
Background It has been suggested that the sympathetic nervous system might play an important role in the development of coronary artery
spasm. However, no cardiac imaging modality has been able to demonstrate abnormal sympathetic innervation in patients with
coronary artery spasm. The purpose of this study was to assess the presence and location of abnormal sympathetic innervation
using iodine 123-metaiodobenzylguanidine (123I-MIBG) single photon emission computed tomography (SPECT) and to evaluate the clinical efficacy of 123I-MIBG SPECT as a noninvasive screening test in patients with coronary artery spasm.
Methods and Results Coronary arteriography and a provocative test with intravenous administration of ergonovine maleate were performed in 26 patients
(20 men, 6 women, mean age 48.2±12.0 years, range 20 to 67 years) who were suspected of having a coronary artery spasm. The
subjects were divided into 2 groups: group 1 (n=18) comprised subjects with negative provocative provocative test result,
and group 2 (n=8) comprised subjects with negative provocative test results. Ten healthy subjects served as controls. No abnormal
MIBG uptake was observed in the control subjects. Abnormal sympathetic nervous innervation using 123I-MIBG SPECT was observed either as a reduced uptake or a defective pattern in the perfused areas in 13 of the 18 regions
supplied by vessels of ergonovine-induced vasospasm. Normal sympathetic innervation, as evidenced by normal 123I-MIBG uptake, was noted in all of the 60 segments of normal vessel territories. Reduced uptake of 123I-MIBG was not detected in the perfused areas of 5 vasospasm-induced vessels (perfusion territory of left anterior descending
coronary artery [LAD] and the right coronary artery [RCA] in 2 and 3 patients, respectively). The sensitivity and specificity
of 123I-MIBG for detection of coronary artery spasm were 72.2% (95% confidence interval, [CI] 55% to 89%) and 100%, respectively.
The positive predictive and negative predictive values were 100% and 92.3% (95% CI 91% to 93%), respectively.
Conclusion
123I-MIBG SPECT is a feasible method to evaluate noninvasively and localize the territories of coronary arteries with spasm.
Invasive diagnostic coronary arteriography with ergonovine provocation test may be unnecessary for diagnosis of coronary artery
spasm in patients with typical resting pain, negative exercise test or normal thallium perfusion scan results, but showing
abnormalities in 123I-MIBG SPECT.
Presented in part at the European Association of Nuclear Medicine Congress, September 1996, Copenhagen, Denmark. 相似文献
85.
86.
87.
Intestinal schistosomiasis japonica: CT-pathologic correlation 总被引:1,自引:0,他引:1
Lee RC; Chiang JH; Chou YH; Rubesin SE; Wu HP; Jeng WC; Hsu CC; Tiu CM; Chang T 《Radiology》1994,193(2):539
88.
Cecilia Johnsson Gunnar Tufveson Lise Binderup Alex Karlsson-Parra 《Xenotransplantation》1997,4(3):186-193
Abstract: The vitamin D analogue MC 1288 (20-epi-1α,25-dihydroxycholecalciferol) effectively postpones rejection of cardiac, intestinal, skin, and aortic allografts. MC 1288 binds to the vitamin D receptor and is thus assumed to exert its immunosuppressive effects via the same mechanisms as 1α,25-dihydroxycholecalciferol, the active form of vitamin D. 1α,25-Dihydroxycholecalciferol has been demonstrated to inhibit the production of various cytokines (interleukin-2, interferon-γ, granulocyte macrophage colony-stimulating factor, and interleukin-12) and to prevent B lymphocyte secretion of immunoglobulins. In the present study MC 1288 was evaluated for its ability to prevent rejection of mouse-to-rat cardiac xenografts, alone and in combination with 15-deoxyspergualin (DSG). Combined treatment with MC 1288 (given days -1 to 9) and DSG (given day -1 and onward) postponed rejection from day 3.0 (untreated recipients) until day 19.5. In rats treated with MC 1288 or DSG as monotherapy, rejection occurred after 3.0 and 7.5 days, respectively. Functioning grafts, obtained on day 9 from recipients treated with MC 1288 and DSG in combination, displayed an almost normal morphology without any obvious deposition of immunoglobulins in the vessels of the grafts and with just a few infiltrating cells. Thus, we have demonstrated synergistic actions of MC 1288 and DSG in delaying rejection of xenografts. Analysis of cellular infiltration, immunoglobulin deposition and graft survival times in the various treatment groups indicate a combined inhibitory effect of these two drugs on the level of macrophage effector function, direct or indirect via T lymphocytes, as well as on antibody production. 相似文献
89.
Two cases of staphylococcal lung disease in young infants are described. In each instance a life-threatening bronchopleural fistula in the acute phase was successfully managed by thoracotomy and suture repair.
Offprint requests to: A. W. Auldist 相似文献
90.
Routine testing of sediments or suspended sediments for toxicant or genotoxicants by the bioassay route often involves time-consuming and expensive organic extraction procedures. In most instances these extraction procedures are more time-consuming and costly than the bioassays that will be used on these extracts. A direct sediment test procedure (DSTP) was developed to alleviate the problem and thus returning bioassays to one of their original roles, i.e., short, quick, screening tests to identify priority samples for more intensive chemical analysis. The DSTP was developed in conjunction with the Toxi-Chromotest and SOS Chromotest kits. The SOS Chromotest can be used with or without S9. Our results presented in this paper indicate the sensitivity of DSTP and cost effectiveness compared to some commonly used sediment extraction procedures. 相似文献