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101.
102.
Columellar skin defects may be caused by excision of cutaneous malignancy, trauma, or tissue necrosis associated with surgery. Although columellar skin necrosis rarely occurs following rhinoplasty, this condition might be more common when using an external approach than a closed approach. Columellar skin incision performed with exaggerated tip augmentation may cause columellar necrosis. The nasolabial island flap, used unilaterally to cover columellar skin defects, is used for a single-stage reconstruction procedure and is generally not associated with the need for secondary surgeries. This technique is well suited for repairing columellar skin defects. We experienced a patient with columellar skin necrosis occurring after rhinoplasty which was reconstructed using a unilateral single-stage nasolabial island flap.  相似文献   
103.
104.
Patency of cerebral microvessels after focal embolic stroke in the rat.   总被引:5,自引:0,他引:5  
In patients with thrombotic stroke, the occluded artery often reopens over time. This results through a natural dissolution of the occluding material, and fragments of the material may move downstream to obstruct distal arteries. The current study was undertaken to investigate the patency of brain microvessels at varying time intervals after injection of a preformed clot into the right internal carotid artery of rats. Cerebral microvessels in brain sections were visualized using immunohistochemistry for fibronectin (detecting existing microvessels) and Evans blue (visualizing perfused microvessels). The percentage of patent microvessels was calculated as the number of Evans blue-positive microvessels divided by the number of fibronectin-positive microvessels. In normal control animals, results showed that 98% +/- 3% (mean +/- SD) of microvessels in the cortex and 94% +/- 14% in the striatum were patent. In the ischemic animals, immediately after clot injection, microvessels in the cortex and striatum were occluded, mainly in the territory irrigated by the middle cerebral artery. One hour after clot injection, microvessels had reopened in most of the cortex but remained occluded in some portions of the striatum, possibly as a result of downstream movement of fragments formed from the original clot. By 3 hours after clot injection, microvessels in the cortex were patent in all animals, whereas in the striatum microvessels were patent in 50% of the animals. In the other 50%, small striatal perfusion deficits persisted. At 24 hours after clot injection, microvessels were patent in both the cortex and striatum of all animals except one. These findings suggest that intracerebral clots dissolve spontaneously in a relatively short period of time, but that fragments formed from the clot may obstruct more distal blood vessels. It is likely that clot fragments lodge in arteries with lower blood flow and poor collateral perfusion, where they continue to cause ischemia for a longer duration. These results may in part explain the resistance of the striatum to neuroprotective strategies used for the treatment of focal cerebral ischemia.  相似文献   
105.
106.
The extent and severity of neuronal damage is different in ischemia with reperfusion compared to ischemia and no reperfusion. To investigate the role of glutamate in cerebral ischemia–reperfusion injury, in vivo microdialysis was performed to examine the dynamic profile of glutamate in the hippocampus in a transient (30 min) or permanent middle cerebral artery occlusion (MCAo) in Wistar rats. The extracellular concentration of glutamate in the cornu ammonis (CA)1 sector of the ipsilateral hippocampus showed a significant but transient elevation of glutamate for both groups immediately following ischemic insult. The initial high peak in glutamate levels in the transient MCAo group was followed by two secondary elevations in glutamate at 50 min and 90 min after initialization of reperfusion. The histopathological outcome was also different in the two groups. The observation that glutamate releases occurred in the early reperfusion phase provided an evidence of additional excitotoxicity of glutamate and thereby a therapeutic base for extended use of glutamate antagonist in the ischemia–reperfusion injury.  相似文献   
107.
Isolated tuberculosis of the coccyx is extremely rare. A 35-year-old man presented with a 3-month history of coccygeal and gluteal pain. Computed tomography and magnetic resonance imaging revealed osseous destruction and a large enhancing mass involving the coccyx with anterior and posterior extension. Pathologic examination of the surgical specimen revealed necrosis, chronic granulomatous inflammation, and multinucleated giant cells consistent with tuberculosis. This case highlights the importance of considering tuberculosis as a diagnosis even though unusual sites are involved.  相似文献   
108.
This study examines the validity of the diagnosis of stroke on hospital discharge records in Saskatchewan, Canada. In total, 1,494 records with a discharge diagnosis of 'stroke' or a 'stroke-related condition' were reviewed. The clinical algorithm of the 1980 USA National Survey of Stroke was considered the 'gold standard'. The positive predictive value of a primary diagnosis of stroke in the tertiary-care hospitals was about 90%. In community hospitals the majority of stroke cases were coded as ICD9 436 in which the positive predictive value was 78%. The variation between regions would limit the use of hospital discharge data for stroke surveillance.  相似文献   
109.
To determine the outcome of patients with carotid transient ischemic attacks (TIAs) and normal cerebral angiograms, we assessed 68 patients (40 men, 28 women) aged 24-72 (mean 53.5) years for recurrent TIAs and strokes and for the development of cardiac disease over 2-6 (mean 4.4) years. All but one patient had a follow-up interview in early 1987; that patient had died of an unrelated cause (lung cancer) 18 months after the presenting TIA. The diagnosis was changed at the follow-up interview in three patients (multiple sclerosis, meningioma, migraine). Among the 64 remaining patients, at admission cranial computed tomography had shown cerebral infarction in 11 of 64, two-dimensional echocardiography had been abnormal in nine of 61, Holter monitoring had been abnormal in eight of 45, and twelve-lead electrocardiography had been abnormal in three of 64. Two patients had abnormalities on both echocardiography and Holter monitoring. At the follow-up interview of the 64 remaining patients, TIAs had recurred in nine and three had developed a completed stroke; cardiac disease (angina in seven, myocardial infarction in four) was noted in 11 patients. Findings from cardiac investigations on admission in the nine patients with recurrent TIAs had been abnormal in six and normal in three; all three patients who developed a stroke had had abnormal cardiac findings. Overall, further neurologic or cardiac events occurred in 12 of 46 patients (26%) with normal and in 10 of 18 patients (55.5%) with abnormal findings on admission (p less than 0.01). In the presence of normal angiograms, extensive cardiac investigations may help predict the outcome of patients with TIAs.  相似文献   
110.
Percutaneous epididymal sperm aspiration (PESA) and intracytoplasmic sperm injection (ICSI) were carried out in patients with congenital bilateral absence of the vas deferens (CBAVD) and men with failed reversal of vasectomy (FRV). PESA was successful in 55 out of 62 patients with CBAVD (89%) and in 57 out of 60 men with FRV (95%). The fertilization rates after ICSI (53 and 55%), cleavage rates (70 and 76%) and pregnancy rates (36 and 32%) did not differ significantly between the two respective groups (CBAVD and FRV). PESA and ICSI are effective both in patients with CBAVD and in those with FRV.   相似文献   
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