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Changes in the metabolism of copper and zinc are described in aspartylglycosaminuria (AGU) patients. AGU patients had significantly reduced serum zinc concentrations. However, hair zinc levels were normal, and hyperzincuria could not be demonstrated. The copper content in the hair of AGU patients was highly elevated. Serum copper and ceruloplasmin concentrations were within normal range. In AGU, small-molecular-weight glycoasparagine storage products accumulate in tissues and are excreted in urine in large amounts. They may interfere with the transport mechanisms of trace elements, and thus alter their distribution and availability for tissues. The changes in copper and zinc levels may contribute to the pathogenesis of some of the clinical signs of AGU and Salla disease.  相似文献   
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Processing of context information is implicated in prefrontal functions as response selection or attention. N-methyl-D-aspartate (NMDA) receptors in the mammalian prefrontal cortex (PFC) and in the nidopallium caudolaterale (NCL) of birds, the avian functional equivalent of the PFC, are involved in learning, which also requires processing of context. The authors investigated the role of NMDA receptors in the pigeon (Columba livia) NCL for context processing and response selection in a simultaneous-matching-to-sample task with 2 trial types, requiring either processing of context information, delivered by a conditional stimulus (context dependent), or only recall of a stimulus-response association (fixed response). The competitive NMDA antagonist DL-2-amino-5-phosphonovaleric acid impaired performance only in context-dependent trials. Therefore, NMDA receptors in the avian PFC participate in response selection requiring context processing rather than in response selection per se. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The aim of the present study was to formulate stabilized suspension-type metered-dose inhalation aerosols, and to examine the connection between the stabilizing additives and the optimal particle size. For the stabilization of the suspended particles, hydrophilic- and hydrophobic-type additives were applied. Oleil oleate was selected as a hydrophilic anionic surfactant, and the hydrophobizing agent was dimethyl siloxane polymer. The effect of the amount of the applied hydrophilic and hydrophobic additives on the optimal particle size was modeled by a second-order polynomial equation fitted to the data gathered by a face-centered central composite statistical design. We found that if the proper type and amount of additives are selected, it is possible to acquire the therapeutically best composition.  相似文献   
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BACKGROUND: The protective effect of postmenopausal estrogen replacement therapy on coronary heart disease has been shown in several studies. However, the effect on stroke is more controversial, and data on estrogen-progestin combinations are sparse. METHODS: A total of 23,088 women living in the Uppsala (Sweden) Health Care Region were identified from pharmacy records as having been prescribed noncontraceptive estrogens during 1977 through 1980. They were followed up from 1977 to 1983 for admissions to the hospital because of a first stroke (International Classification of Diseases, Eighth Revision, codes 430 through 438 and 344). The mean observation time was 5.8 years. The expected number was based on person-years in the cohort and incidence rates in the population of the region. RESULTS: Overall, 361 cases of first stroke were observed in the cohort, as compared with 403.2 expected (relative risk [RR], 0.90; 95% confidence limits, 0.81, 0.99). The RR for acute stroke (International Classification of Diseases, Eighth Revision, codes 431 through 436) was 0.85 (0.75, 0.97). In women younger than 60 years at entry who were prescribed estradiol compounds (1 to 2 mg) or conjugated equine estrogens (0.625 to 1.25 mg), the risk of any stroke was reduced by almost 30% (RR, 0.72; 0.58, 0.88) and the risk of acute stroke was reduced by 40% (RR, 0.61; 0.46, 0.79). Women prescribed a combined estradiol-levonorgestrel brand also had a lowered risk of stroke (RR, 0.61; 0.40, 0.88). Weak compounds (mainly estriol) showed no stroke-protective effect, nor was there any relationship between hormone replacement and risk of subarachnoid hemorrhage. CONCLUSION: Hormone replacement therapy with potent estrogens alone or cyclically combined with progestins can, particularly when started shortly after menopause, reduce the risk of stroke.  相似文献   
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The calcium content of mud patches used for therapy is very small. Several mineral clays originating from Hungary served as a base material for experiments in order to find a suitable drug for transdermal introduction of calcium ions into the body. The Ca++ transport through the pig skin has been investigated in vitro in diffusion cells applying iontophoresis. Studies of electrical and physicochemical factors acting on the permeation kinetics of in vitro experiments were performed. The utilization of direct current has intensified the Ca++ transport through the pig skin (129.78+/-26. 15 microgram Ca/cm2). On using pulsate currents the amount of the Ca++ penetrating through the skin was 5-10 times higher (283.18+/-16.89 microgram Ca/cm2, 388.71+/-19.90 microgram Ca/cm2) than that of the passive transport (36.22+/-14.20 microgram Ca/cm2). The amount of Ca++ cumulated in the receptor compartment was directly proportional to the amount of bentonite (a natural mineral clay with a large cation exchange capacity) in the donor compartment and to the concentration of Ca++ in the lattice of the applied mineral clay. Therefore, the experiments were carried out on a bentonite previously enriched in Ca++ in its lattice (50 mg Ca/g bentonite). The results of the in vitro studies could open a new field of application in the therapy of osteoporosis or in the use of mineral substances.  相似文献   
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A fast and reliable diagnostic system has been developed for the detection of Mangalica meat in foods. This qualitative test is based on a recombinase polymerase amplification which can be performed on the field, in situ, where it may be necessary to determine Mangalica content in food products at once. The required equipments for the procedure are pipettes, a portable homogenizer and a portable thermostat. DNA amplification is carried out at a constant temperature, and the detection is based on antibody reaction. The detection limit is one copy of the target sequence in 1 μl reaction volume. The test can be used for uncovering falsification of local brands on the spot within a very short (25–45 min) period of time. The present approach can be adopted for the detection of other food ingredients, if the species-specific target DNA sequence is known, e.g. in case of chicken, turkey, horse, and cattle.  相似文献   
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LetA be a finite dimensional associative algebra over the fieldF whereF is a finite (algebraic) extension of the function fieldF q(X 1,...,X m). Here Fq denotes the finite field ofq elements (q=pl for a primep). We address the problem of computing the Jacobson radical Rad (A) ofA and the problem of computing the minimal ideals of the radical-free part (Wedderburn decomposition). The algebraA is given by structure constants overF andF is given by structure constants overF q(X 1,...,X m). We give algorithms to find these structural components ofA. Our methods run in polynomial time ifm is constant, in particular in the casem=1. The radical algorithm is deterministic. Our method for computing the Wedderburn decomposition ofA uses randomization (for factoring univariate polynomials overF q).Research partially supported by Hungarian National Foundation for Scientific Research (OTKA), Grants 2581, F4116 and EC Cooperative Action IC 1000 (ALTEC).  相似文献   
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