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排序方式: 共有1085条查询结果,搜索用时 15 毫秒
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A longitudinal study to estimate the serum calcium, phosphate and alkaline phosphatase levels of 89 ambulatory epileptic children, aged between 3 years and 12 years, and having generalised tonic-clonic seizures, was carried out. None was on any form of medication for the treatment of seizures prior to presentation. Each patient received only phenobarbitone during the period of study. Serum levels of the biochemical parameters were determined at presentation, 6 months and 12 months, while serum phenobarbitone levels were estimated at 6 months and 12 months. Mean serum calcium, phosphate and alkaline phosphatase of the patients remained within the normal range. Using the paired 't' test, the differences in the levels of the parameters at the three measurements were not statistically significant (P > 0.05). Serum phenobarbitone levels remained within the therapeutic range during the period of study. Our results show that over a 12-month period, serum levels of calcium, phosphate, and alkaline phosphatase, remain normal in ambulant epileptic children treated with phenobarbitone. 相似文献
3.
AD Rossi E Ahlbom SO Ogren P Nicotera S Ceccatelli 《Canadian Metallurgical Quarterly》1997,117(3):428-436
In the present study the neurotoxic effects of a low dosage (0.5 mg/kg per day) of methylmercury (MeHg) on the developing nervous system were investigated. Pregnant rats were treated with MeHg from day 7 of pregnancy to day 7 of lactation. Locomotor activity (locomotion, rearing, and motility) and spatial learning ability were tested in the offspring at 6 months of age. The expression of tyrosine hydroxylase (TH) was examined by immunohistochemistry and in situ hybridization. A significant decrease in spontaneous motility and rearing was observed only in the MeHg-treated male rats. After administration of a low dose of d-amphetamine (0.5 mg/kg) no differences could be observed between control and MeHg-treated male rats, suggesting that changes in dopaminergic transmission were involved. However, no change in TH messenger RNA expression was observed. No changes in spatial learning acquisition or memory were shown in MeHg-treated rats. Taken together, these findings show that during development a very low dosage of MeHg exerts neurotoxic effects detectable in adulthood, and that susceptibility is gender-dependent. 相似文献
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Abstract: Maintainability problems associated with traditional software systems are exacerbated in rule-based systems. The very nature of that approach — separation of control knowledge and data-driven execution — hampers maintenance. While there are widely accepted techniques for maintaining conventional software, the same is not true for rule-based systems. In most situations, both a knowledge engineer and a domain expert are necessary to update the rules of a rule-based system. This paper presents, first, an overview of the software engineering techniques and object-oriented methods used in maintaining rule-based systems. It then discusses alternate paradigms for expert system development. The benefits of using case-based reasoning (from the maintenance point of view) are illustrated through the implementation of a case-based scheduler. The main value of the scheduler is that its knowledge base can be modified by the expert without the assistance of a knowledge engineer. Since changes in application requirements can be given directly to the system by the expert, the effort of maintaining the knowledge base is greatly reduced. 相似文献
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The photosensitizing properties of p-nitroacetophenone (PNAP), a well-known radiosensitizer, have been studied in near UV region. The mechanism of PNAP photosensitization has been investigated by testing the efficiency of singlet oxygen production using photooxidation of 2,2,6,6-tetramethylpiperidine (TEMP) and photodegradation of guanosine. In both the cases, the enhancement effect of deuterated solvents has been observed. Results of these experiments suggest the significant role of type II mechanisms in PNAP photosensitization. 相似文献
7.
G Bioque D Vargas O Bulbena J Roselló-Catafau Gelpi E 《Canadian Metallurgical Quarterly》1993,38(1-2):38-43
N-phenyllinoleamide (NPLA) has been detected as extraneous compound in adulterated cooking oils associated with a unique epidemic disease known as the Toxic Oil Syndrome (TOS). In this communication we report on the action of NPLA on the endogenous cyclooxygenase and lipoxygenase arachidonate metabolism. Results show that mouse peritoneal macrophages (MPM) exposed to 1 mM NPLA for 2 h undergo significant increases of 6-keto prostaglandin F1a, prostaglandin E2, leukotriene B4, 12- and 15-hydroxyeicosatetraenoic acids. MPM prelabelled with 3H-AA showed an enhanced release when exposed to NPLA. Thus, it is concluded that NPLA potentiates AA release from cell membrane phospholipids and the subsequent cyclooxygenase and lipoxygenase oxidative metabolism of this precursor to various eicosanoids. This is in agreement with the implication of peroxidative process mediated by fatty acids anilides in TOS. 相似文献
8.
SO Trertola SJ Savader CA Prescott FA Osterman 《Canadian Metallurgical Quarterly》1993,189(1):285-286
A simple commercially available compression device allowed intermittent ultrasound scanning of the compression site during compression repair of a femoral artery pseudoaneurysm in six patients. All six of the pseudoaneurysms (five superficial femoral and one common femoral) were compressed without compression of the underlying vessels. The procedure was successful in four of the six patients, without complications. Use of this device may decrease operator fatigue during compression repair of pseudoaneurysm. 相似文献
9.
AIM: To evaluate a new enzyme immunoassay (EIA) method for detection of Clostridium difficile toxin by comparing it to cytotoxicity assay. To investigate the nature of false negative and false positive EIA results by evaluating clinical and therapeutic parameters. METHODS: 737 consecutive diarrhoeal specimens collected from patients clinically suspected of having C difficile colitis were tested for the presence of C difficile toxin by EIA for toxin A and by cytotoxicity assay. Clinical data were evaluated in all cases positive by either method. RESULTS: With the cytotoxicity assay as a gold standard, the specificity of EIA for toxin detection was 99.3% and the sensitivity was 62.2%. No false negative EIA specimens were obtained from patients already being treated for C difficile colitis. Among patients with cytotoxicity positive specimens, those with EIA positive samples had no clinical features distinguishing them from patients with EIA negative samples. CONCLUSIONS: Although specific, the new EIA method directed against toxin A lacks sensitivity compared to cytotoxicity. False negative EIA tests are not associated with concurrent treatment for C difficile colitis nor with any specific clinical features examined in our study. 相似文献
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