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991.
It is noted that the increased central sympathetic nerve activity caused by neurovascular compression at the rostral ventrolateral medulla (RVLM) is closely related to the genesis of neurogenic hypertension. The authors present the case of a 49-year-old female with refractory neurogenic hypertension to be uncontrolled even with all kinds of oral antihypertensive medications. After approval by the Ethical Committee in a hospital, she had received an intravenous introduction of calcium antagonist and beta-blocker at home for three years. The subsequent examination detail showed increased sympathetic nerve activity and compression of the left vertebral artery (VA) at the left RVLM on magnetic resonance imaging, and therefore microvascular decompression (MVD) underwent through a left lateral suboccipital approach. The left VA was seen indenting the left RVLM. To ensure the complete decompression, the distal part of VA was moved away from RVLM to fix to the dura of the petrous bone with a glue. Her blood pressure became normalized afterwards without drugs and remained normotensive for 23 months after MVD. In order to decide the surgical indication for pure neurogenic hypertension due to neurovascular compression, a strict differential diagnosis is necessary. 相似文献
992.
"Firefly rats" as an organ/cellular source for long-term in vivo bioluminescent imaging 总被引:3,自引:0,他引:3
BACKGROUND: Transplantation research involving the use of stem cells demands an appropriate in vivo visualization system to monitor cellular fate over an observation period. The new field of in vivo imaging is being developed with fluorescent and luminescent biotechnology, and involves the real-time visualization of complex cellular processes in living animals. METHODS.: Following our recent development of inbred green fluorescent protein (GFP)-transgenic (Tg) rats, we created the establishment of inbred (Lewis) Tg rats with firefly luciferase. The immunogenicity against luciferase was evaluated by the skin grafting test, and the fate of grafts was monitored by in vivo luminescent technique. RESULTS.: The luciferase-Tg rats ubiquitously expressed the marker gene. Conventional skin grafting apparently showed the long-term acceptance of luciferase-Tg rat skin on wild-type rats (>100 days), compared with grafting of GFP-Tg-derived skin (<10 days). This suggests less cellular immune responsiveness against the luciferase protein than GFP. Strikingly, organ transplants with heart and small bowel, and bone marrow cell transplantation showed viability and graft acceptance, demonstrating that cells and organs from luciferase-Tg rats are transplantable and their fate can be tracked for a sufficient time. Taking advantage of less immunogenic luciferase, cellular fate of transplanted mature hepatocytes was also examined. Transplanted hepatocytes proliferated and were monitored selectively in damaged liver, but not in healthy liver, for over 60 days. CONCLUSIONS: We propose on the basis of these findings that the luciferase-Tg rat system with modern optical imaging offers a new platform for a better understanding of stem cell biology and transplantation. 相似文献
993.
994.
Shibuya S Kawaguchi Y Arima N Yamamoto T Dobashi H Tokuda M 《Journal of neurosurgery. Spine》2006,5(5):451-454
Tumoral calcinosis commonly occurs in the articular soft tissues of the extremities but rarely in the spine. The authors performed surgery to treat lumbar tumoral calcinosis in a patient with scleroderma, in whom symptoms of neurological dysfunction had manifested. This 49-year-old woman presented with low-back pain and gait disturbance. Seven years before presentation, scleroderma had been diagnosed, and the patient had received medical treatment ever since. Imaging revealed tumoral calcinosis centered at the bilateral facet joints between L-3 and L-4, marked stenosis of the spinal canal, L-3 spondylolisthesis, and intervertebral instability. Surgery was performed to excise the lesion en bloc. After neural decompression, posterolateral fusion and pedicle screw fixation were undertaken. Symptoms improved after surgery. In this case, the underlying scleroderma that predisposes to calcinosis and facet joint degeneration due to lumbar spondylolisthesis were probably factors leading to the development of tumoral calcinosis in the lumbar spine. 相似文献
995.
Honda M Ezaki Y Kitagawa N Tsutsumi K Ogawa Y Nagata I 《Surgical neurology》2006,66(2):155-9; discussion 159
OBJECTIVES: We quantified the rCBF and regional vascular reserve (CVR) in adult patients with moyamoya disease before and after surgery using IMP I 123 SPECT. METHODS: The patient population included 5 adult patients with ages at presentation ranging between 23 and 42 years. One patient had stroke, whereas 4 patients had transient ischemic attacks. RESULTS: Before surgery, the mean resting rCBF and mean CVR in the frontal, parietal, and temporal lobes of the surgically treated hemisphere were 40.09, 39.50, and 36.9 mL/100 g per minute and 15.39%, 27.09%, and 28.92%, respectively. After surgery, the rCBF increased significantly (P = .0002, .0005, and .0062), but in a CVR evaluation, only the frontal lobe increased significantly (P = .0055). In the unaffected hemispheres, the mean resting rCBF significantly increased only in the frontal lobe (P = 038) and no significant increase in the CVR was observed after surgery. In 2 patients who showed steal phenomenon induced by acetazolamide administration, CVR significantly increased not only in the frontal lobe but also in the parietal and temporal lobe after surgery, although the CVR in these areas significantly decreased both before and after surgery in comparison to the mean CVR in all patients. CONCLUSIONS: The frontal lobe showed severe hemodynamic ischemia. The cerebral hemodynamics in patients with moyamoya disease improved after surgical intervention, especially in severely damaged patients. Split-dose (123)I-IMP SPECT was therefore found to be a useful diagnostic modality for quantifying the hemodynamics of moyamoya disease. 相似文献
996.
997.
Iida Y Sugimoto T Katsu M Shimada K Yamamoto K Yoshii S Kasuya S 《Kyobu geka. The Japanese journal of thoracic surgery》2006,59(7):580-584
A 78-year-old female was admitted to our hospital because of sudden onset of chest pain and general fatigue. A chest X-ray showed marked cardiomegaly and computed tomography (CT) revealed pericardial effusion with left pleural effusion. Upon admission to CCU, she suddenly lost consciousness and was intubated. Echocardiography confirmed increase in the amount of the pericardial effusion, which was drained at CCU. By an emergent operation, ruptured aneurysm of the noncoronary sinus of Valsalva to the pericardial space was confirmed upon opening the chest and patch plasty of the sinus of Valsalva was performed. The postoperative course was uneventful, and she was discharged on the 24th postoperative day. Extracardiac rupture of aneurysm of the sinus of Valsalva is extremely rare, and the emergent operation is indispensable. 相似文献
998.
Natural course of incidentally found nonfunctioning pituitary adenoma, with special reference to pituitary apoplexy during follow-up examination 总被引:1,自引:0,他引:1
Arita K Tominaga A Sugiyama K Eguchi K Iida K Sumida M Migita K Kurisu K 《Journal of neurosurgery》2006,104(6):884-891
OBJECT: The increase in the incidental detection of asymptomatic pituitary adenomas, known as "pituitary incidentalomas," led the authors to conduct a survey of the natural course of these lesions. METHODS: Forty-two patients with clinically nonfunctioning pituitary adenomas who had manifested no neurological or endocrinological disorders were monitored with magnetic resonance imaging studies. The follow-up period ranged from 10.8 to 168.2 months (mean +/- standard deviation, 61.9 +/- 38.2 months). The mean initial tumor size was 18.3 +/- 7 mm. In 21 patients, the tumor increased by at least 10% of its measured size on detection. This increase was first detected between 8.4 and 58.8 months (mean 31.8 +/- 17.6 months) after diagnosis. There was no correlation between the original tumor size, patient age, or the presence of intratumoral cysts and tumor growth. Symptoms were noted in 10 patients during follow up; in four, extensive tumor necrosis accompanied hemorrhage, leading to severe headache, acute ophthalmological symptoms, and panhypopituitarism, which was indicative of pituitary apoplexy. Transsphenoidal surgery was performed in 12 patients with enlarged tumors, including three with apoplexy. With the exception of one apoplectic patient, visual function was recovered in all who underwent surgery. All apoplectic patients continue to manifest hypopituitarism. CONCLUSIONS: In the course of 4 years, the size of the incidentalomas increased in 40% of 42 patients and became symptomatic in 20%. During the 5-year follow up, pituitary apoplexy developed in 9.5%. These findings may justify early intervention, especially in young individuals with incidentally found macroadenoma. 相似文献
999.
Segawa N Kotake Y Noumi H Uchimoto S Azuma H Katsuoka Y Tsuji M 《Hinyokika kiyo. Acta urologica Japonica》2006,52(7):565-567
Primary tumor originated from ureteral stump following nephrectomy for benign disease is extremely rare. A 79-year-old male was referred to our department for asymptomatic macroscopic hematuria. He had undergone left simple nephrectomy for renal tuberculosis 52 years ago. Cystoscopic examination revealed a ureteral tumor on the residual ureteral orifice. Under the diagnosis of left ureteral stump tumor, which was subsequently enhanced on computer tomographic scan and magnetic resonance imaging, he received partial cystectomy and excision of the left ureteral stump. The histological examination revealed grade 2 to 3 urothelial carcinoma with muscle invasion (pT2). He received no adjuvant chemotherapy. He is now alive and free from recurrence 2 months post-operatively. This is the 21st case reported in the Japanese literature. 相似文献
1000.
Inoue H Kase S Sato E Ichiki A Kuno Y Arai T Sato Y Okuda Y 《Masui. The Japanese journal of anesthesiology》2006,55(9):1164-1167
We monitored sublingual tissue PCO2 (PSLCO2) continuously with an ISFET (ion-sensitive field effect transistor) based PCO2 sensor during and after surgical treatment for descending aortic aneurysm. Using femoro-femoral bypass and a beating heart technique, distal end of aneurysm was clamped and then selective cerebral perfusion was performed into the left subclavian and left common carotid arteries. Aneurysmectomy and reconstructive surgery were carried out with proximal end of the left common carotid artery being clamped. Upon starting selective cerebral perfusion, PSLCO2 increased abnormally. PSLCO2 increased from 38 mmHg just after induction of anesthesia to the maximum value of 87 mmHg during selective cerebral perfusion. Three hours after arriving in the intensive care unit, the patient developed convulsion and anisocoria and the computed tomography showed cerebral infraction. Since the blood flow to the tongue is fed through the internal and external carotid arteries, the increase in PSLCO2 is supposed to be caused by the decrease of blood flow to the tongue during selective cerebral perfusion. The monitoring of PSLCO2 may be a useful method to estimate the brain blood flow during selective cerebral perfusion. 相似文献