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991.
The effects of anoxia and hypoxia (3% oxygen) at 10–12 post days of age on the development of ventral hippocampal kindling and its transfer to the contralateral ventral hippocampus were studied in adult male Sprague-Dawley rats. During oxygen deprivation, the heart rate decreased to 15% of the prehypoxic value in the animals exposed to anoxia and 40% in those exposed to hypoxia. As is observed in asphyxia of human newborns, our study included both ischemia and hypoxia. The susceptibility to kindling, which was measured by kindling rate, afterdischarge threshold, generalized seizure threshold, and total afterdischarge duration to stage 5, had a tendency to be enhanced in rats exposed to hypoxia compared with controls. The facilitating effects on primary site kindling were enhanced in the animals exposed to hypoxia compared with those exposed to anoxia. Transfer, which was indicated by kindling rate and afterdischarge threshold, was also slightly facilitated in the rats exposed to anoxia or hypoxia in the perinatal period. These results reveal that perinatal oxygen deficiency may not be sufficient to lead to the development of temporal lobe epilepsy. However, it is possible that perinatal hypoxia results in some pathophysiological change in the brain which leads to greater seizure susceptibility in adulthood.  相似文献   
992.
We present herein two successfully treated cases of focal nodular hyperplasia (FNH) of the liver, a relatively rare disease. Case 1 was a 3 year old child in whom typical FNH developed in the left lateral segment of the liver, whereas Case 2 was a 22 year old man in whom characteristic findings were lacking on preoperative diagnostic imaging. Scintigraphy was not performed in either case, however, postoperative histological examination confirmed FNH. Thus, in patients with a hypervascular tumor and normal liver function, FNH should be strongly suspected and a series of scintigraphy proposed. Both cases showed a negative association with oral contraceptive intake but no other obvious etiology was suggested.  相似文献   
993.
The protective effect of a new oligomeric derivative of prostaglandin B2, known as OC-5186, was evaluated using time-sharing spectrofluorometry in the coldpreserved rat liver. Experiments were divided into three groups: in group A, a 5000 ng dose of OC-5186 was administered via the peripheral vein, 1000 ng via the portal vein, and 200 ng/ml in University of Wisconsin (UW) solution; in group B, the OC-5186 dosage was ten times greater than that in group A; in group C (control group), liver procurement and storage were performed without OC-5186. At 0, 12, and 24 h after cold preservation at 4°C, the liver was perfused for 30 min at 12°C with oxygenized Krebs-Henseleit solution, after which the perfusate was switched to deoxygenized Krebs-Henseleit solution. Time sharing spectrofluorometry was used to follow NADH fluorescence at 450 nm with a 360-nm excitation wavelength, as well as the reflectance of cytochrome aa 3 with 605 minus 620 nm from oxidation to reduction. Rate constants of NADH fluorescence and cytochrome aa 3 reflectance were used as indices of integrity of the mitochondrial respiratory chain. In group C, the rate constant of NADH fluorescence decreased significantly (P<0.05) from the control value of 8.31±0.21×10-3 (sec-1) to 4.97±0.15×10-3 and 5.58±0.16×10-3 (mean±SEM) at 12 and 24 h after cold preservation, respectively. By contrast, in groups A and B, the rate constant of NADH fluorescence was maintained at significantly (P<0.05) higher levels of 6.57±0.54×10-3 and 7.29±0.48×10-3, and 6.94±0.44×10-3 and 6.86±0.44×10-3 at 12 and 24 h, respectively. The rate constant of cytochrome aa 3 reflectance between the OC-5186 groups and the control group was not significant. It is concluded that OC-5186 has a protective effect on the mitochondrial respiratory chain against cold-preservation and/or reperfusion injury.  相似文献   
994.
995.
We evaluated the serum levels of major basic protein (MBP), assayed using an MBP radioimmunoassay kit. and the effect of an anti-allergic agent, ketotifen, which has strong anti-eosinophil activity, in 56 atopic dermatitis (AD) patients. The serum MBP level was significantly lower (660.11 ± 34.52 ng/ml, P < 0.05) after administration of ketotifen (1 mg twice a day) for 8 weeks than before treatment (774.98 ± 48.64 ng/ml). These findings suggest that serum MBP levels are a useful indicator of AD activity and that anti-allergic agents can have an effect on eosinophil involvement in AD.  相似文献   
996.
Effect of GDF-5 on ligament healing.   总被引:4,自引:0,他引:4  
The effects of growth and differentiation factor-5 (GDF-5) on ligament healing were studied using a gap injury model of the medial collateral ligament in rat knee joints. The administration of GDF-5 once at the time of surgery significantly improved the mechanical properties of the femur-ligament-tibia complex. At 3 weeks after surgery, 30 microg of GDF-5 improved the ultimate tensile strength of the complex by 41%, and the stiffness by 60%, compared with the vehicle control (p < 0.05 for both; Fisher's PLSD test). The observation with a transmission electron microscopy revealed that GDF-5 increased the diameter of collagen fibrils in the repair tissue, which was considered to be a possible mechanism for the positive result in the biomechanical testing. Quantitative PCR and in situ hybridization revealed enhanced type I procollagen expression by GDF-5, and the PCR analysis also revealed that the GDF-5 treatment reduced the expression of type III procollagen relative to type I procollagen. The PCR analysis further showed that the expression of decorin and fibromodulin was relatively reduced against type I procollagen by the growth factor, which was considered to be responsible for the increase of collagen fibril diameter in the repair tissue. No adverse effects were observed, and the use of GDF-5 was considered a promising approach to facilitate ligament healing.  相似文献   
997.
Our previous study suggested that 3D-CT angiography could replace digital subtraction (DS) angiography in most cases of ruptured cerebral aneurysms, especially in the anterior circulation. This study reviewed our further experience. One hundred and fifty patients with ruptured cerebral aneurysms were treated between November 1998 and March 2002. Only 3D-CT angiography was used for the preoperative work-up study in patients with anterior circulation aneurysms, unless the attending neurosurgeons agreed that DS angiography was required. Both 3D-CT angiography and DS angiography were performed in patients with posterior circulation aneurysms, except for recent cases that were possibly treated with 3D-CT angiography alone. One hundred sixteen (84%) of 138 patients with ruptured anterior circulation aneurysms underwent surgical treatment, but additional DS angiography was required in 22 cases (16%). Only two recent patients were treated surgically with 3D-CT angiography alone in 12 patients with posterior circulation aneurysms. Most patients with ruptured anterior circulation aneurysms could be treated successfully after 3D-CT angiography alone. However, additional DS angiography is still necessary in atypical cases. 3D-CT angiography may be limited to complementary use in patients with ruptured posterior circulation aneurysms.  相似文献   
998.
PURPOSE: Pulse dye-densitometry, a novel monitor that measures circulating blood volume (CBV) and cardiac output (CO), was used in patients with pheochromocytoma to determine the relationship between CBV and post resection hypotension. METHODS: Case control study. An alpha blocker was administered for approximately two weeks, and its effect on the expansion of CBV was quantified. CBV was monitored in seven patients admitted for resection of suspected pheochromocytoma before preoperative alpha-blocker therapy, after alpha-blocker therapy and three times during the operation. Relationships between the CBV and blood pressure after resection of the tumour were examined. RESULTS: CBV increased from 72.0 +/- 10.0 mL.kg(-1) to 83.4 +/- 12.2 mL.kg(-1) after alpha blockade. (P < 0.001). We found a significant inverse relationship between the increase in CBV after alpha-blocker therapy and blood pressure after resection of the tumour. CONCLUSIONS: Expansion of the CBV by alpha-blocker therapy was related to lower blood pressures after resection of the pheochromocytoma. Expansion of the CBV by an alpha blocker may have increased the elastance of blood vessels. Preoperative blood volume expansion does not preclude hypotension after tumour resection. Although the CBV value itself is not a predictor for hypotension after tumour resection, pulse dye-densitometry provides values of CO and CBV simultaneously, assisting in the management of volume resuscitation and/or the need for catecholamines.  相似文献   
999.
Intractable perineal pain often appears in the anal region following abdominoperineal resection for the treatment of rectal cancer. In such cases, a subarachnoid block or transsacral block is generally used to control pain. However, these procedures sometimes cause complications such as dysuria or sensory paralysis of the pudendum. A new method of pain control is presented herein using absolute alcohol as a neurolytic agent to relieve localized perineal pain through a coccygeal nerve block in the anterior sacrococcygeal ligament. Five cadavers were necropsied to localize the coccygeal nerve. A loop consisting of S4, S5, and Co was found to exist in the space surrounded by the anterior surface of the coccygeal bone and the anterior sacrococcygeal ligament. Absolute alcohol was injected into this space. It is essential that the neurolytic agent remain localized in this space to avoid complications and to successfully block perineal pain. In all patients, we found that this method was extremely effective in blocking localized perineal pain without any complications.  相似文献   
1000.
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