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991.
Chung YH  Shin CM  Joo KM  Kim MJ  Cha CI 《Brain research》2002,951(2):1496-321
In the present study, we examined age-related changes in 3-nitrotyrosine (NT) and neuronal nitric oxide synthase (nNOS) in rat cerebellum using immunohistochemistry. No immunoreactivity for NT was found in any layers of adult cerebellar cortex. In aged cerebellar cortex, the most prominent labeling of NT was found in the Purkinje cell layers and molecular layers. In aged cerebellar nuclei, NT immunoreactivity was observed in the surrounding neuropil. In aged rat cerebellum, nNOS immunoreactivity was significantly decreased in the molecular layer, while it was slightly increased in the granular layer. Image analysis showed no significant age-related changes in nNOS immunoreactivity in the cerebellar nuclei. In summary, this report has demonstrated that NT increases with age in the cerebellum, and suggests that NO production by the neuronal form of NOS may not be the rate limiting step in NT formation in the aged brain. Further work is needed to examine the mechanisms underlying the increased immunoreactivity for NT, and the functional implications of this increase.  相似文献   
992.
993.
Sequencing the mitochondrial control region is very useful for individual identification when conventional DNA typing using autosomal STRs is unavailable. However, low discriminatory power is a problem and another polymorphic locus within the mitochondrial genome is necessary. The cytochrome B (MTCYB) gene, which has undergone several changes during evolution, may be a good candidate for this purpose. Here the sequencing data of the MTCYB gene of 98 unrelated Koreans is presented. A total of 30 polymorphic sites were found which were distributed evenly along the gene. All were nucleotide substitutions and no insertions/deletions were noted. A total of 22 different MTCYB lineages were revealed. Out of 22 different control region lineages with 79 samples which shared the same D-loop sequence with some others within a lineage, 10 lineages with 37 samples could be sub-grouped according to different MTCYB sequences. Some issues concerning the MTCYB gene polymorphism are discussed. Received: 10 January 2001 / Accepted: 29 May 2001  相似文献   
994.
The purpose of this study was to investigate the suitability of a new nitinol monofilament stent (Niti-S) for transjugular intrahepatic portosystemic shunt (TIPS) creation. TIPS was performed with a Niti-S stent in 22 patients for variceal bleeding (n = 20) or intractable ascites (n = 2). The efficacy, complication, and patency rates during the follow-up period (up to 27 months, mean 13.9 months) were evaluated. TIPS was successfully performed in all patients. The mean portosystemic pressure gradient decreased from 23.8 ± 7.2 mmHg to 10.2 ± 3.1 mmHg. No mortality or significant morbidity was encountered at 1 month. Variceal bleeding and/or ascites were controlled in all patients. Primary patency rates were 77.3% at 6 months and 71.8% at 1 year. Secondary patency rates were 95.4% up to 26 months. TIPS with the Niti-S stent produced short-term technical and clinical results comparable to the other commercially available stents. A prospective randomized comparison study is indicated.  相似文献   
995.
OBJECTIVE: The purpose of this study was to evaluate the efficacy of eptifibatide, an inhibitor of the glycoprotein (GP) IIb/IIIa platelet receptor, in the thrombolytic treatment of patients with acute peripheral arterial occlusive disease. MATERIALS AND METHODS: We retrospectively reviewed our experience with the use of a GP IIb/IIIa receptor inhibitor, eptifibatide, during thrombolysis in 17 patients with acute lower extremity arterial occlusions who also received intraarterial recombinant tissue plasminogen activator (rt-PA) and heparin. Four of the 17 patients received their loading dose of eptifibatide by direct intraarterial injection, whereas the remaining 13 received an IV loading dose. We compared their results with those of 11 other patients who received only rt-PA and heparin with respect to success and complication rates, duration of thrombolytic therapy, and total rt-PA dose. RESULTS: We found no significant difference in successful outcome (p = 1.00), major complications (p = 1.00), duration of therapy (p = 0.21), or total rt-PA dose (p = 0.67) between those who received eptifibatide and those who did not during thrombolytic therapy. However, those patients who received an intraarterial loading dose of eptifibatide required substantially less rt-PA (9.0 +/- 4.4 mg vs 38.9 +/- 30.7 mg) to achieve successful thrombolysis. CONCLUSION: The adjunctive use of a GP IIb/IIIa platelet receptor inhibitor during thrombolysis for arterial occlusions may decrease the total dose of rt-PA required for thrombolysis without compromising success or complication rates. A prospective randomized study is needed to confirm that inhibitors of the GP IIb/IIIa platelet receptor can facilitate thrombolytic therapy in patients with acute lower extremity arterial occlusions.  相似文献   
996.
Human envenomation caused by bee stings has been reported to cause acute renal failure and the pathogenetic mechanisms of these renal functional changes are still unclear. Bee venom is also a complex mixture of enzymes and proteins. Thus, this study was conducted to examine the effects of bee venom (BV, Apis mellifera) fractions on apical transporters' activity and its related signal pathways in primary cultured renal proximal tubule cells. Whole BV was extracted into three fractions according to solubility [a water-soluble fraction (BVA), an ethylacetate-soluble fraction (BVE), and a hexane-soluble fraction (BVH)]. BVA fraction was further separated to three portions according to molecular weights: BF1 (>20 kD), BF2 (10-20 kD), and BF3 (<10 kD). Each fraction was treated to the PTCs to the ratio of BV (1 microg/ml). BVA (930 ng/ml) significantly decreased cell viability, but BVH (27 ng/ml) and BVE (43 ng/ml) did not. BF3 (710 ng/ml) among BVA fractions predominantly decreased cell viability and inhibited alpha-methyl-D-glucopyranoside (alpha-MG), phosphate (Pi), and Na(+) uptake. In addition, BF3 increased [(3)H] arachidonic acid release, lipid peroxide formation, and Ca(2+) uptake. These effects of BF3 were blocked by mepacrine and AACOCF(3) (phospholipase A(2) inhibitors) or N-acetylcysteine, vitamin C, and vitamin E (antioxidants). In conclusion, BF3 (<10 kD) among BV fractions is the most effective portion in BV-induced inhibition of alpha-MG, P(i), and Na(+) uptake and these effects of BF3 are associated with phospholipase A(2)-oxidative stress-Ca(2+) signal cascade in the primary cultured rabbit renal proximal tubule cells.  相似文献   
997.
Significance of acute multiple brain infarction on diffusion-weighted imaging   总被引:39,自引:0,他引:39  
BACKGROUND AND PURPOSE: Diffusion-weighted imaging (DWI) is superior to conventional MRI in identification of small new ischemic lesions and discrimination of recent infarcts from old ones. Thus, this technique is useful in the detection of acute multiple brain infarcts (AMBI). We sought to determine the frequency and the topographical and etiologic patterns of AMBI detected on DWI. METHODS: We studied 329 consecutive ischemic stroke patients who underwent DWI and MRI/MR angiography within 4 days of stroke onset. AMBI was defined as noncontiguous high signal intensities on DWI in >1 vascular territory. Stroke mechanism was determined according to the criteria of the Trial of Org 10172 in Acute Stroke Treatment (TOAST). RESULTS: We detected AMBI in 95 patients (28.9%). AMBI in anterior circulation was found in 62 cases: in 1 hemisphere in 42 (group A) and in bilateral hemispheres in 20 (group B). Twenty-two patients had AMBI in the posterior circulation (group C) and 11 in both anterior and posterior circulations (group D). The most frequent cause of stroke was large-artery atherosclerosis in groups A (33/42), B (9/20), and C (15/22) (P=0.02) and cardioembolism in group D (6/11) (P=0.02). Elevated fibrinogen or hematocrit was significantly associated with group B (P=0.01). In 9 patients in groups B and D, anatomic variations of anterior or posterior cerebral arteries or patent posterior communicating artery contributed to AMBI. CONCLUSIONS: Different topographical patterns of AMBI are associated with different vascular pathologies and stroke mechanisms. Hemorheologic abnormality or vascular anatomic variations may be contributing factors in the pathogenesis of AMBI in bilateral cerebral hemispheres or in both anterior and posterior circulations.  相似文献   
998.
Purpose: To compare follow-up results of sclerotherapy for renal cyst using 50% acetic acid with those using 99% ethanol as sclerosing agents. Methods: Eighty-one patients underwent sclerotherapy and 58 patients, 23 males, 35 females, aged 6–76 years, having a total of 60 cysts, were included in this study; the others were lost to follow-up. The renal cysts were diagnosed by sonography, computed tomography (CT), or magnetic resonance imaging (MRI). Sclerotherapy was performed using 50% acetic acid for 32 cysts in 31 patients and 99% ethanol for 28 cysts in 27 patients. Under fluoroscopic guidance, cystic fluid was aspirated as completely as possible. After instillation of a sclerosing agent corresponding to 11.7%–25% (4–100 ml) of the aspirated volume, the patient changed position for 20 min and then the agent was removed. Patients were followed up by sonography for a period of 1–49 months. The volume of the renal cyst after sclerotherapy was compared with that of the renal cyst calculated before sclerotherapy. Medical records were reviewed to analyze complications. Results: The mean volume after sclerotherapy of the 17 cysts followed for 3–4 months in the acetic acid group was 5.1% of the initial volume, and for the 14 cysts in the ethanol group it was 10.2%. Complete regression during follow-up was shown in 21 cysts (66%) in the acetic acid group; the mean volume of these cysts before the procedure was 245 ml. The mean volume of the nine (32%) completely regressed cysts in the ethanol group was 184 ml. Mild flank pain, which occurred in three patients in each group, was the only complication and resolved the next day. Conclusion: Acetic acid was an effective and safe sclerosing agent for renal cysts, tending to induce faster and more complete regression than ethanol.  相似文献   
999.
Sj?gren's syndrome (SS) is a systemic lymphoproliferative, autoimmune disease, which is characterized by dryness of the eyes, mouth, and other mucous membranes. The nervous system may be affected in up to 20% of the cases of primary or secondary SS. We present a case of a 54-year-old woman with trochlear nerve palsy complicating Sj?gren's syndrome secondary to rheumatoid arthritis. We suggest that all patients with multiple cranial neuropathies, especially when associated with rheumatoid arthritis, should be carefully examined for the possible presence of secondary SS.  相似文献   
1000.
Background Surgical excision of orbital lymphangiomas is difficult, and almost always incomplete due to the diffusely infiltrative pattern of these tumors. The present report describes the successful use of intralesional OK-432 administration to treat two patients with intractable hemorrhagic proptosis due to orbital lymphangiomas. Methods A 3-year-old girl (case 1) presented with aggressive proptosis and ptosis, and a 1-year-old boy (case 2) presented with massive proptosis and exposure keratopathy, associated with recurrent intracystic bleeding of an orbital lymphangioma. In case 1, 0.02 mg OK-432 was intracystically injected in a volume of 2 ml of physiologic saline. Due to a lack of therapeutic response, a second injection of 0.05 mg OK-432 in 1 ml was administered. In case 2, a single dose of 0.05 mg OK-432 in 1 ml was administered. Results In both cases, intracystic administration of 0.05 mg of OK-432 in a 1-ml volume resulted in a successful outcome. The adverse effects were minor (mild transient fever and lid swelling), and rebleeding and intraocular pressure elevation did not occur. Proptosis and eyelid swelling gradually improved over 1 month, and completely resolved within 3 months of treatment. Conclusions Intralesional administration of 0.05 mg/ml OK-432 (delivered in 1 ml) resulted in the successful treatment of two cases of orbital lymphangioma. Although this drug concentration is higher than in previous reports, there were no major adverse effects. No proprietary interests existed, and the authors received no financial support.  相似文献   
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