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41.
Glutathione content and glutathione-dependent enzymes were measured in the liver of two fish species, gudgeon (Gobio gobio) and roach (Rutilus arcasii), from the river Bernesga (Spain) caught downstream and upstream of the waste site of several chemical industries. Animals from contaminated sites display a reduced glutathione concentration and a tendency to the decrease of glutathione S-transferase activity. Glutathione peroxidase activity was significantly elevated only in the liver of Gobio gobio and glutathione reductase activity in that of Rutilus arcasii. Our data indicate that the glutathione system constitutes a sensitive biochemical indicator of chemical pollution. Relative changes of glutathione and glutathione-dependent enzymes in both fish species suggest a different susceptibility to toxins.  相似文献   
42.
A new method is described for thein-situ measurement of electrical resistivity of concrete structures. The method is based on the early work of J. Newman who calculated the electrolyte resistivity between a disk and a counter electrode located at infinity. This method has the advantage compared with Wenner's of using a single small electrode for the measurements. In this paper, results are presented comparing this method with Wenner's and with results carried out using a conductivity cell in electrolytes. Finally, values of resistivity are compared to corrosion intensity, and a threshold for active corrosion is suggested.
Résumé On décrit une nouvelle méthode de mesure de la résistivité électrique du béton dont la technique est basée sur un travail ancien de J. Newman qui avait calculé la résistivité entre un disque et une électrode auxiliaire placée à l'infini. Comparée à la méthode de Wenner, cette méthode présente l'avantage de n'utiliser, pour les mesures, qu'une petite électrode. Dans cet article, on présente les résultats de la comparaison établie avec la méthode de Wenner et avec les résultats obtenus avec une cellule de conductivité placée dans les électrolytes. Enfin, on compare les valeurs de la résistivité du béton avec celles de l'intensité de la corrosion et on suggère un seuil de corrosion active.


Editorial note Camen Andrade and Maria-Cruz Alonso are working at the Instituto Eduardo de Torroja which is a RILEM Titular Member. Dr. Andrade, who was the 1986 RILEM Medallist, have had all these years great responsibilities within RILEM. Chairlady of the Advisory Technical Committee until 1993, she is now a member of the Coordinating Committee. She is active in 116-PCD Technical Committee on Permeability of Concrete as a Criterion of its Durability and has been appointed chairdlady of 154-EMC Technical Committee on Electrochemical Techniques for Measuring Metallic Corrosion. Carmen Andrade has been appointed RILEM Fellow in 1995.  相似文献   
43.
Phase separation during polymerization was studied in a model system consisting of a diepoxide based on diglycidyl ether of bisphenol A (DGEBA), variable amounts of ethylenediamine (EDA) and the mass of castor oil (CO) necessary to obtain a mass fraction equal to 0-15 in a final system where the stoichiometric ratio of amine to epoxy equivalents, r, was equal to 1. A two-step polymerization process was performed by curing first a system with r = 0-5, during variable times before phase separation, and then carrying the system to r = 1. Thermodynamic analysis of samples with different r values led to a linear relationship between the Flory-Huggins interaction parameter and r. The concentration (P) and average size (D?) of dispersed-phase particles followed opposite trends, i.e. P increased while D? decreased, when either r was increased or the time of curing in the first step of a two-step process was decreased. This was explained by assuming that the competition between nucleation and growth was determined by the viscosity at the cloud point, ηcp. Low values of ηcp favoured growth over nucleation and led to fewer but larger particles.  相似文献   
44.
Whether a sulfonylurea may be used together with insulin for treating NIDDM has been controversial. One view, based on older studies, has been that the additional benefit is too small or the level of glucose control achieved usually too poor to recommend this method. More recent studies of a more specific way of combining a sulfonylurea with insulin are more supportive. When a single injection of insulin taken in the evening is added to a sulfonylurea at the time of secondary failure of the sulfonylurea alone, glycemic control is quite simply and consistently restored to acceptable levels. At this time in the natural history of NIDDM, evening insulin combined therapy is more effective than a single injection of insulin alone, and just as effective as a more complex multiple-injection regimen without an oral agent. A recent multicenter trial of a new sulfonylurea, glimepiride, in combination with a single injection of 70/30 insulin before dinner has confirmed that this approach is safe and more consistently effective than insulin alone for obese patients beginning insulin in a setting resembling clinical practice. The available evidence suggests this form of combined therapy is suitable for routine use.  相似文献   
45.
OBJECTIVE: Retrospective study of urological complications in our series of reno-pancreatic transplants. MATERIAL AND METHODS: Between February 1983 and May 1994 our group has conducted 93 RPT, 80 of which, mean age 36 +/- 6 years (24-54 years), are studied in this paper: 57 male and 23 female with an average time in dialysis of 20 +/- 15 months (0-84 months) and diabetes evolution of 21 +/- 5 years (11-37 years). RESULTS: Actuarial annual survival of patient, renal graft and pancreatic graft has been 85%, 79% and 74% respectively. Haematuria: 25% incidence, with graft pancreatitis etiology in 16 cases, rejection in 8 and urinary fistula in 6. Urinary infection: 85% incidence, symptomatic in 23 patients (29%) and asymptomatic in the remaining cases. Dysuria, urethritis and urethral stenosis: 14 patients, all male, most with both conditions associated. Reconversion of pancreatic exocrine secretion by intestinal route was performed in 7 patients. Urinary fistula: secondary to surgery in 9 cases and rejection in 4. Etiology of one case remained unknown. In 4 cases it was resolved with conservative treatment, and with surgical correction in 8. One patient required pancreatic transplantectomy and one patient died of AMI. CONCLUSIONS: Urological complication in RPT account for a significant morbidity, urinary fistula being the one with greater repercussion on the patient and pancreatic graft survival.  相似文献   
46.
47.
In Costa Rica the mollusk Anadara tuberculosa represents a risk for human health due to the contamination of the growing waters and the fact that its is consumed raw. The families depending on the income obtained through commercialization of these animals have a low education and economic status. Therefore, it is of great importance to develop and evaluate simple methods of depuration that could be easily used by these families to make these mollusks safe for consumption. Bottles containing 11 of saline solution (25g/l) were prepared in duplicates to test the bactericidal effect of acetic acid. The solution in each bottle was adjusted to ph 4.5, 5.0 or 5.5 or held at ph of 7.0 or 8.0 for the controls. The solution in each bottle was then inoculated with approximately 1 X 104 cfu/ml of coliforms. Counts of coliforms were determined for each bottle 0, 1, 2, 4 and 8 hours after inoculation. For the depuration studies, specimens with diameters ranging from 4.0 to 4.5 cm were collected from a harvester at the estuary of Puntarenas, Gulf of Nicoya. Fifty specimens each were depurated in separate tanks containing 25 1 of oxygenated saline solution adjusted with acetic acid to an initial ph of 4.5 (treatment) or non adjusted ph of 8.0 (control). Counts of Enterobacteriaceae were determined, in duplicates, every 12 hr for 48 hr. An additional fifty animals were depurated using the defined method and tested to determine if they met international standards of microbiological quality for aerobic plate count, Enterobacteriaceae count, Escherichia coli count and presence of Salmonella. A sensory evaluation using a triangle test was performed to compare a typical dish prepared with depurated or non-depurated animals. A significant coliform reduction was determined in a saline solution (25 g/l) at a pH range of 4.5 to 5.5. This reduction, during 8 hr, was higher in the acid treatments compared to the controls. During depuration, the elimination of Enterobacteriaceae bacteria was faster when acetic was used (initial ph = 4.5) than when it was not. This elimination was more important the first 24 hr, time defined as adequate for the application of the method. The method has the advantage of transforming the bivalve in a product that is safe for human consumption, since it guarantees that the international standards of microbiological quality, for raw and depurated mollusks, are reached. On the other hand, the sensory qualities of a typical dish prepared with depurated animals are not affected by the method, which can be easily implemented and applied by the people that work in the extraction of this mollusk.  相似文献   
48.
BACKGROUND: It is not clear if old age is a risk factor for adverse drug reactions. AIM: To study the incidence of adverse drug reactions and the effect of age in patients admitted to an Internal Medicine Service in an university hospital. PATIENTS AND METHODS: Two hundred one patients, hospitalized at the Clinical Hospital of the Catholic University, were studied. These patients were followed using a prospective pharmacological surveillance method. For statistical purposes, patients aged 65 years old or older were compared with those younger than 65 years old. RESULTS: Patients over 65 years old had a 33% incidence of adverse drug reactions, mainly involving cardiovascular system and provoking metabolic disturbances. Younger subjects had a 24% incidence of adverse drug reactions, mainly involving the gastrointestinal system and the skin. Sixteen percent of adverse drug reactions were classified as severe and there was a direct relationship between its frequency and the number of drugs prescribed, the hospitalization length and the presence of renal failure. Younger patients with adverse drug reactions had lower serum albumin levels than those without adverse reactions. This relationship was not observed in older patients. CONCLUSIONS: The frequency of adverse drug reactions in hospitalized patients, is related to the number of drugs prescribed and the length of hospitalization.  相似文献   
49.
Discusses the theoretical and clinical applications of the postmodern paradigm of social constructionism as a basis for counseling culturally different clients. Such applications avoid the trap of perpetuating the status-quo when working with minority and marginalized clientele. The main points of multiculturalism and social constructionism are summarized, and issues of mutual concern to both perspectives are examined. Applications to psychotherapy are explored, and the challenges of applying the social constructionist approach to culturally competent counseling are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
50.
This research summary discusses the application of neural networks, evolutionary strategies, and other artificial intelligence techniques in the modeling and optimization of the models used for temperature, rolling force, and torque calculation in heavy plate milling.  相似文献   
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