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91.
We have developed a new type of glassy carbon electrode whose smooth surface with scattered craters reduces its polarization voltage. It has both excellent antithrombogenicity and slight tissue reaction. The energy threshold curve was the lowest when compared to the Siemens (411S, 412S) and the Solin (S-100) electrodes.  相似文献   
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Subpopulations of interleukin-2 receptor (IL-2R)-positive CD4 and CD8 T cells and IL-2R+ CD20 B cells in the peripheral blood lymphocytes as well as serum concentrations of soluble IL-2R (sIL2R) were measured in children aged 1–7 years who suffered acute severe asthmatic attack. Subpopulations of CD4+ IL-2R+ cells, CD8+ IL-2R+ cells and CD20+ IL-2R+ cells in the peripheral blood lymphocytes at acute severe asthmatic attack phase were significantly higher than those at non-asthmatic attack phase (P < 0.02, P < 0.03 and P < 0.02, respectively). Subpopulations of CD20+ IL-2R+ cells in the peripheral blood lymphocytes significantly decreased 5–10 days after acute severe asthmatic attack (at recovery phase, P < 0.02) and were significantly correlated with clinical severity of asthmatic attack (P < 0.05). These results indicated that activation of both T cells and B cells was important in the pathogenesis of acute asthmatic attack in young children.  相似文献   
95.
We examined the relationship between MRI lesions and electro-clinical findings with special attention to the localising value of aura sensations and the sides of interictal epileptiform discharges in 327 patients with symptomatic localisation-related epilepsy. As a result, while autonomic as well as psychic auras were correlated with temporal lesions, simple motor seizures were associated with extra-temporal ones. Within the group of patients with temporal lobe epilepsy, autonomic but not psychic auras concurred significantly more often with medial temporal structural lesions. Furthermore, there was a significant difference between concordance rates between sides of MRI lesions and EEG foci as a function of laterality: while the right-sided MRI lesions constantly showed ipsilateral EEG foci, EEG foci concurring with the left-sided MRI lesions proved to be often falsely lateralising. From these results, we assumed that lateral as well as medial temporal involvement is needed in the genesis of the psychic aura in contrast to the autonomic aura, which could be induced without lateral temporal involvement, and lesions in the left hemisphere are more apt to induce secondarily epileptogenic than those in the right hemisphere.  相似文献   
96.
Among 114 patients with thyroid disease examined by 201Tl-chloridescintigraphy, 101 were given a histological diagnosis. Of 28cases of thyroid carcinoma, 22 (78.6%) were positive. In threeof the 22, an obvious accumulation of 201Tl-chloride was revealedin the metastatic lymph nodes of the neck and mediastinum. Only 12 of 50 (24%) cases of thyroid adenoma were positive.In comparison, all cases of hyperthyroidism and chronic thyroiditiswere positive and all cases of subacute thyroiditis were negative.The histological types of thyroid tumor were examined. Of 22cases of papillary carcinoma, 18 (81.8%) were positive. In fourcases which revealed negative figures, the tumor was almostcompletely encysted in three and the tumor was small in theother. Of the adenomas, eight cases of tubular adenoma and threeof trabecular adenoma were all positive, but colloid adenomaand thyroid cyst cases were all negative. It was concluded that 201Tl-chloride has no specific affinityfor malignant tumors and cannot be used to discriminate betweencarcinoma and adenoma, but surgery should be indicated for noduleswhich are positive scanning by 201Tl-chloride.  相似文献   
97.
BACKGROUND: To compare urinary oxalate excretion after the oral administration of oxalic acid, disodium oxalate, or calcium oxalate in rats. METHODS: Male Wistar rats were divided into four groups of six rats each and were intravenously hydrated with normal saline, and then were administered normal saline (control group), 10 mg of oxalic acid, equimolar disodium oxalate, or equimolar calcium oxalate via a gastrostomy. Urine specimens were collected just before administration and at hourly intervals up to 5 h afterwards. The urinary oxalate, calcium, magnesium and phosphorus levels were measured. RESULTS: Urinary oxalate excretion peaked at 1-2 h after administration of oxalic acid or equimolar disodium oxalate, while administration of calcium oxalate only caused a small increase of urinary oxalate excretion. Cumulative urinary oxalate excretion during 5 h was 1.69 +/- 0.10 mg (mean +/- SD; 17%), 1.43 +/- 0.13 mg (13%), and 0.22 +/- 0.03 mg (2%) after the administration of oxalic acid, disodium oxalate, and calcium oxalate, respectively. Urinary calcium excretion showed a decrease in the oxalic acid and disodium oxalate groups, while urinary magnesium or phosphorus excretion did not change significantly. CONCLUSION: The upper gastrointestinal tract seems to be the major site of oxalic acid absorption and only free oxalate is absorbed irrespective of whether it is the sodium salt or not. After binding to calcium in the gut, oxalic acid absorption seems to be inhibited in the presence of calcium and this means that calcium oxalate is poorly absorbed (at least in the upper gastrointestinal tract).  相似文献   
98.
To investigate whether the efficacy of intraoperative laser ablation therapy is affected by myocardial blood perfusion, we irradiated 11 canine hearts through the epicardium with a Nd:YAG laser (10, 20. and 30 J/mm2) using air as the medium. Compared coagulated myocardial depth, width, and volume obtained in the red beating heart was compared with those in the white nonbeating heart infused with CC saline (cardioplegic model) via the coronary artery. Histologically, the macro- and microscopical findings were very similar. At each level of energy, the width and volume of red myocardium coagulated were significantly larger than those of white myocardium (P < 0.01). At 30 J/mn2, the depth of coagulation of red myocardium was significantly larger than that of white myocardium (P < 0.01). The coagulated volume of the white myocardium was about 60% of that of the red myocardium. NdiYAG laser energy was absorbed by blood (red color = hemoglobin), and more energy was transferred in the higher temperature myocardium. During intraoperative Nd:YAG laser ablation, the presence of blood perfusion in cardiac tissue is thought to be an important factor affecting safe irradiation.  相似文献   
99.
Abstract— The tablet surface was evaluated without physical damage by means of Fourier-transform infrared reflection-absorption spectroscopy (FT-IR-RAS) and colorimetric measurement (colour difference, AE) of the carbamazepine polymorphs I, II and III, after photodegradation at two irradiation intensities (30 and 120 J cm?2 s ?1) under a near-UV fluorescent lamp. The surface of sample pellets of all crystalline forms turned gradually from white to yellow-orange upon exposure to light, and the discoloration rate of form II was faster than that of forms I and III, indicating that form II was the most unstable of the three. The major photoproducts were identified by HPLC, NMR and MS analyses. The carbamazepine content on the surface of the tablet was determined based on the absorption at 1685 cm?1 atributable to C = O stretch vibration in the FT-IR-RAS spectra before and after irradiation by a near-UV fluorescent lamp. The semilogarithmic plots of the photodegradation profiles of the various polymorphs were straight lines, including the induction period, indicating that degradation of the drug on the surface followed first-order kinetics. The induction periods of all forms were not significantly different. However, the degradation rate constant of form II at 12.0 Jcm?2 s ?1 was 5·1 and 1·5 times larger than those of forms I and III, respectively.  相似文献   
100.
Serum α2-macroglobulin-trypsin complex (α2M-T) was measured to differentiate the elevation of serum pancreatic enzymes caused by severe acute pancreatitis from simple elevation after endoscopic retrograde pancreatography (ERP). A patient with severe acute pancreatitis demonstrated marked elevation of serum α2M-T. In patients without severe acute pancreatitis, serum αM-T did not rise in spite of elevated serum pancreatic enzymes. In conclusion, abdominal pain with elevated serum α2M-T can be an early diagnostic clue to severe acute pancreatitis after ERP.  相似文献   
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