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91.
Diana A. Lepore Kenneth R. Knight Surajit Bhattacharya Morris Ritz Sonia P. Robbins Peter Sieg Wayne A. Morrison Bernard McC. O'Brien 《Microsurgery》1994,15(10):685-692
The chief aim of this study was to maximize flap survival by counteracting the pathophysiological changes occurring during ischemia-reperfusion. Rabbit epigastric skin flaps given 21 hours of ischemia were infused intra-arterially with selected drugs at the start of reperfusion. Compared with control infused ischemic flaps, which had a 33% survival rate on day 7 post-ischemia, significant improvement was found with vasodilators nitrendipine (61%) and prostacyclin (65%) and the thrombolytic agent urokinase (65%); marginal improvement with the free radical scavenger desferrioxamine (53%); but no change with streptokinase (44%), heparin (21%), and ATP-MgCl2 (35%). A drug mixture comprising all of these agents except streptokinase and urokinase produced 87% survival, suggesting an additive effect. Biochemical assays on skin homogenates and blood implicated oxygen free radicals, neutrophil infiltration, and thromboxane in flap failure. These results imply that multiple factors are responsible for ischemic flap failure and that a mixture of drugs needs to be infused to counteract all of the detrimental changes. © 1994 Wiley-Liss, Inc. 相似文献
92.
Linda G. Rabinowitz M.D. Nancy B Esterly M.D. Ilona J. Frieden M.D. Gregory S. Garbin M.D. Roy C. Grekin M.D. T. J. Stafford M.D. Ph.D. O. T. Tan M.D. Linda G. Rabinowitz M.D. Gerald N. Goldberg M.D. Karen F Rothman M.D. Lynne J. Roberts M.D. Roy G. Geronemus M.D. Susan B. Mallory M.D. Jerome M. Garden M.D. Joseph G. Morelli M.D. Moise L Levy M.D. Bernard A. Cohen M.D. 《Pediatric dermatology》1992,9(2):132-153
One of the most exciting developments in pediatric dermatology has been the use of the flashlamp-pumped, 585-nm, pulsed dye laser for treatment of vascular birthmarks. In many cases the results are miraculous. The increase in self-esteem and happiness of many children and adolescents has been overwhelming; for some, depression has been lifted, stuttering has ceased, social involvement has increased, and antidepressants have been discontinued. There are many success stories to tell.
Despite the remarkable effects of the pulsed dye laser and the medical and psychosocial indications for its use, the issue of pain control remains significant. We have no perfect outpatient pediatric anesthetic. Most methods carry either some risk or, if not hazardous, often are not very effective for controlling pain. Needless to say, a diversity of opinions exist on how to manage discomfort from this treatment modality. Therefore, we thought it would be useful to share the experiences and opinions of several dermatologists who have extensive experience with the pulsed dye laser. 相似文献
Despite the remarkable effects of the pulsed dye laser and the medical and psychosocial indications for its use, the issue of pain control remains significant. We have no perfect outpatient pediatric anesthetic. Most methods carry either some risk or, if not hazardous, often are not very effective for controlling pain. Needless to say, a diversity of opinions exist on how to manage discomfort from this treatment modality. Therefore, we thought it would be useful to share the experiences and opinions of several dermatologists who have extensive experience with the pulsed dye laser. 相似文献
93.
Ambulatory blood pressure in patients with Parkinson's disease without and with orthostatic hypotension 总被引:1,自引:0,他引:1
Jean-Michel Senard Bernard Chamontin André Rascol Jean-Louis Montastruc 《Clinical autonomic research》1992,2(2):99-104
Non-invasive ambulatory recordings of blood pressure and heart rate were performed using a Spacelabs device during day and night periods in patients with Parkinson's disease with (n = 19) or without orthostatic hypotension (n = 19). In patients with orthostatic hypotension, the average systolic and diastolic blood pressure during the night (137 ± 5/80 ± 3 mmHg) was higher (p < 0.05) than during the day period (121 ± 3/76 ± 2 mmHg). In patients without orthostatic hypotension, a decrease in blood pressure was recorded during the nocturnal period. In patients with orthostatic hypotension, the blood pressure variability was higher (p < 0.05) during the day (systolic: 14.6 ± 1.3%; diastolic: 16.5 ± 1.0%) than during the night (systolic: 9.1 ± 0.8%; diastolic: 10.8 ± 1.1%). The blood pressure load (percentage of values above 140/90 mmHg) during the night was significantly higher than during the day for both systolic (41.2 ± 8.1 vs. 19.6 ± 4.7%) and diastolic blood pressure (24.9 ± 6.9 vs. 16.3 ± 4.9%). There was a decrease in heart rate in both groups during the night. A fall of 25 mmHg or more in systolic blood pressure after meals occurred in ten patients with orthostatic hypotension and in one patient without orthostatic hypotension. These results indicate that orthostatic hypotension in Parkinson's disease is associated with specific modifications of ambulatory blood pressure including loss of circadian rhythm of blood pressure, increased diurnal blood pressure variability and post-prandial hypotension. 相似文献
94.
95.
In a patient with clinical manifestations suggestive of brain malformation, CT showed lissencephaly with absent opercularization. The child had seizures but not a typical EEG of hypsarhythmia. MRI confirmed the diagnosis and showed heterotopic grey matter and abnormal basal ganglia. High grey-white matter contrast and the possibility of imaging the brain in sagittal, coronal and transverse planes make MRI the methode of choice for the evaluation of lissencephaly and other brain malformations. 相似文献
96.
BALB/c mice were bilaterally implanted with bipolar electrodes either in anterodorsal (ADH) or posteroventral hippocampus (PVH) in order to compare the effects of postsession electrical stimulation on memory processes. For each experiment, 30 s after the end of the first session, the animals were stimulated during 80 s. For both hippocampal regions, the stimulation intensity was half of the afterdischarge threshold value. Control groups were naive, ADH and PVH implanted non-stimulated animals. Different appetitive and aversive tasks were used. Subseizure stimulation never created a deficit. Depending on the region of the hippocampus stimulated and on the learning task, a retention enhancement was eventually observed. These data are in agreement with the involvement of hippocampus in initial stages of memory consolidation. Further, the subseizure stimulation permitted a functional dissociation between the two hippocampal regions. Both regions seemed involved in the integration of information, but the anterodorsal part would be rather related to behavioral inhibition, while the posteroventral part would have the capacity to induce an arousal state allowing behavioral flexibility. 相似文献
97.
98.
Elke Wezenberg Robert Jan Verkes Ge S F Ruigt Wouter Hulstijn Bernard G C Sabbe 《Neuropsychopharmacology》2007,32(6):1272-1283
Ampakines act as positive allosteric modulators of AMPA-type glutamate receptors and facilitate hippocampal long-term potentiation (LTP), a mechanism associated with memory storage and consolidation. The present study investigated the acute effects of farampator, 1-(benzofurazan-5-ylcarbonyl) piperidine, on memory and information processes in healthy elderly volunteers. A double-blind, placebo-controlled, randomized, cross-over study was performed in 16 healthy, elderly volunteers (eight male, eight female; mean age 66.1, SD 4.5 years). All subjects received farampator (500 mg) and placebo. Testing took place 1 h after drug intake, which was around Tmax for farampator. Subjects performed tasks assessing episodic memory (wordlist learning and picture memory), working and short-term memory (N-back, symbol recall) and motor learning (maze task, pursuit rotor). Information processing was assessed with a tangled lines task, the symbol digit substitution test (SDST) and the continuous trail making test (CTMT). Farampator (500 mg) unequivocally improved short-term memory but appeared to impair episodic memory. Furthermore, it tended to decrease the number of switching errors in the CTMT. Drug-induced side effects (SEs) included headache, somnolence and nausea. Subjects with SEs had significantly higher plasma levels of farampator than subjects without SEs. Additional analyses revealed that in the farampator condition the group without SEs showed a significantly superior memory performance relative to the group with SEs. The positive results on short-term memory and the favorable trends in the trail making test (CTMT) are interesting in view of the development of ampakines in the treatment of Alzheimer's disease and schizophrenia. 相似文献
99.
A unique example of a gingival salivary gland choristoma together with a gingival cyst is described in a human autopsy specimen of periodontal tissues. A choristoma is a tumor-like growth which is derived from primordial cells which have been displaced from their original tissue or organ. Only 6 other examples of the gingival salivary gland choristoma have been described in the world literature. 相似文献
100.