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排序方式: 共有3797条查询结果,搜索用时 15 毫秒
1.
M C Post J G L M Luermans H W M Plokker W Budts 《Catheterization and cardiovascular interventions》2007,69(1):9-14
Migraine is a common neurological disorder with a great impact on the quality of life and social activities. The patent foramen ovale (PFO) is an intra-atrial right-to-left shunt with a prevalence of 25% in the general population. An increased prevalence is found in patients with migraine, especially in migraine with aura. Percutaneous PFO closure might decrease the prevalence of migraine. However, most of these observational studies were retrospective without a randomized design and the results need to be interpreted with caution. In this review we describe the association between PFO and migraine and the different pathophysiological hypotheses, which have been proposed to explain this relationship. 相似文献
2.
A new method is presented for studying mediator release in isolated peritoneal cells of the rat. Using a superfusion technique, cells can be maintained in a continuously cleared medium. Cells were stimulated with antigen, compound 48/80 or A23187 to characterize this preparation. In addition, inhibitory effects of theophylline, isoprenaline and cromoglycate on compound 48/80-induced histamine release were studied. We conclude that superfusion is a valid alternative to study mediator release from isolated peritoneal cells. 相似文献
3.
Organic nitrates are used for the treatment of angina pectoris symptoms, acute coronary syndrome and for acute and chronic heart insufficiency. In spite of the proven effectiveness of organic nitrates for acute cases, long-term therapy is limited by to the development of tolerance. Recent animal experiments, as well as clinical data, show that an endothelial dysfunction is also induced, a disquieting point, especially considering the negative prognostic impact of endothelial dysfunction. Due to these side effects, the published guidelines of the American Heart Association and the American College of Physicians do not recommend the use of long-term nitrates, such as mono- and dinitrate, for the treatment of stable angina pectoris. Rather, if good left ventricular function is present the calcium antagonist amlodipine should be used. In cases of appreciably reduced left ventricular function, there is a current discussion, based on the recently published A-HeFT study, as to whether a combination therapy with organic nitrates and the effective arteriole dilator hydralazine is beneficial for patients with severe heart insufficiency. 相似文献
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Andrew M Speer Mark W Willis Peter Herscovitch Margaret Daube-Witherspoon Jennifer Repella Shelton Brenda E Benson Robert M Post Eric M Wassermann 《Neuropsychopharmacology》2003,54(8):818-825
BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) affects the excitability of the motor cortex and is thought to influence activity in other brain areas as well. We combined the administration of varying intensities of 1-Hz rTMS of the motor cortex with simultaneous positron emission tomography (PET) to delineate local and distant effects on brain activity. METHODS: Ten healthy subjects received 1-Hz rTMS to the optimal position over motor cortex (M1) for producing a twitch in the right hand at 80, 90, 100, 110, and 120% of the twitch threshold, while regional cerebral blood flow (rCBF) was measured using H(2)(15)O and PET. Repetitive transcranial magnetic stimulation (rTMS) was delivered in 75-pulse trains at each intensity every 10 min through a figure-eight coil. The regional relationship of stimulation intensity to normalized rCBF was assessed statistically. RESULTS: Intensity-dependent rCBF increases were produced under the M1 stimulation site in ipsilateral primary auditory cortex, contralateral cerebellum, and bilateral putamen, insula, and red nucleus. Intensity-dependent reductions in rCBF occurred in contralateral frontal and parietal cortices and bilateral anterior cingulate gyrus and occipital cortex. CONCLUSIONS: This study demonstrates that 1-Hz rTMS delivered to the primary motor cortex (M1) produces intensity-dependent increases in brain activity locally and has associated effects in distant sites with known connections to M1. 相似文献
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Trichloroethylene and halothane inhibit uptake and metabolism of 5-hydroxytryptamine in rat lung slices 总被引:1,自引:0,他引:1
The effect of exposure to organic solvents on uptake and metabolism of 5-HT was studied in rat lung slices. It was found that under control conditions 5-HT was both taken up and metabolized to 5-HIAA. When halothane (35,000 ppm) or trichloroethylene (18,000 ppm) were equilibrated with the incubation medium the uptake of 5-HT decreased by approximately 50% after 30 min of incubation, and the production of 5-HIAA was inhibited by approximately 70% and 80%, respectively. The results are consistent with earlier studies using a much more elaborate technique, in which halothane and trichloroethylene were found to depress 5-HT uptake in isolated perfused rat lungs. Our results demonstrate that the simpler technique employing lung slices can also be used, to investigate factors affecting pulmonary uptake of endogenous amines, and, potentially, the uptake of other compounds as well. 相似文献
8.
Suzanne D. LeBlang M.D. Diego B. Nuñez M.D. Anton Serafini M.D. Robert C. Duncan Ph.D. M. Judith Donovan Post M.D. Berta M. Montalvo M.D. Jose I. Becerra M.D. 《Emergency radiology》1997,4(4):191-199
The purpose of this study was to evaluate the ability of helical computed tomography (CT) to detect arterial injuries in gunshot wounds to the neck. In a blinded retrospective review, 54 helical CT scans of the cervical spine were evaluated for bullet/bone fragments, subcutaneous air, bullet path, hematoma, spine fractures, and pharyngoesophageal compromise. The distance of fragments to a major vessel was calculated. CT findings that correlated significantly with major arterial injury included the presence of fragments (bullet/bone) close to a major vessel (2.5 mm) and spine fractures. Visualizing fragments <5 mm from a vessel or a transcervical bullet trajectory predicted 12 of 13 major arterial injuries. We conclude that CT clearly depicts anatomic damage. Specific findings, such as the location of fragments and bullet trajectory adjacent to a vessel and spine fractures, indicate a higher probability of vascular damage, thus directing more definitive evaluation. 相似文献
9.
Success of meniscal repair with early or immediate motion depends on the ability of the suture fixation to withstand the loads applied. Vertical and horizontal mattress suture techniques were tested using 2-0 Ethibond, and 0-PDS and 1-PDS sutures (Ethicon, Somerville, NJ). Mulberry knot technique was tested with 0-PDS and 1-PDS sutures. Twenty menisci (60 sutures) were tested for each suture material. Sutures were placed 3 to 4 mm from the peripheral edge of the meniscus with double barreled cannulas for vertical and horizontal mattress techniques or a spinal needle for the mulberry knot technique, reproducing clinical techniques of meniscal repair. Mechanical testing of suture fixation was performed to failure at a rate of 10 mm/min on a MTS material testing system (MTS Systems Corp. Minneapolis, MN). Suture pullouts were reported as the load displacement to failure from the inner fragment only, because clinical failure would ensue should a suture pull through the inner fragment of a tear. Vertical mattress technique with 1-PDS suture had significantly greater load to failure than any other combination (P < .05). Analysis of variance showed that the vertical mattress technique had statistically superior pullout strength (P < .0001) compared with the horizontal mattress and mulberry knot techniques, which were statistically similar. There were significant differences (P < .0001) between suture types, with 1-PDS proving best compared with 0-PDS, which was stronger than 2-0 Ethibond. Selection of suture material had the greatest impact on vertical mattress load to failure and was not important to the strength of the other techniques. 相似文献
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