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31.
R Torres-Jiménez F Mateos-Antón J Arcas-Martínez I Pascual-Castroviejo J García-Puig 《Canadian Metallurgical Quarterly》1998,27(160):1050-1054
OBJECTIVE: Hypoxanthine-guanine phosphoribosyltransferase (HPRT) deficiency is characterized by an increase in renal uric acid excretion, usually with hyperuricemia and may be associated with more or less important neurological symptoms. Based on a series of 20 patients from 16 Spanish families we propose that HPRT deficiency could be clinically classified in four different groups. In the more severe form (classic Lesch-Nyhan syndrome) HPRT deficiency is characterized by choreoathetosis, spasticity, mental retardation and compulsive self-mutilation behavior. The pathophysiology of the neurological symptoms remains unclear and there is no effective therapy. This review is intended to provide a research strategy for a better knowledge of the neurological pathophysiology of HPRT deficiency. DEVELOPMENT: We have analyzed the knowledge on the neurological symptoms of HPRT deficiency. This knowledge comes from histopathological studies of the brains from Lesch-Nyhan patients, chemical studies of the cerebrospinal fluid, experimental animal models (pharmacologic and lesioning and genetic approaches), and human in vivo studies with positron-emission tomography. CONCLUSIONS: The observed findings suggest that the neurological symptoms of Lesch-Nyhan syndrome could be related with the neonatal neuronal and/or dopaminergic terminations damage. This damage could be due to lost or reorganization of dopaminergic system, and is associated with a reduced dopamine levels and with hypersensitivity of the D1 subclass dopamine receptors. 相似文献
32.
JE García-Arrarás L Estrada-Rodgers R Santiago II Torres L Díaz-Miranda I Torres-Avillán 《Canadian Metallurgical Quarterly》1998,281(4):288-304
Echinoderms are the deuterostome group with the most striking capacity to regenerate lost body parts. In particular, members of the class Holothuroidea are able to regenerate most of their internal organs following a typical evisceration process. Such formation of new viscera in an adult organism provides a unique model to study the process of organogenesis. We have studied this process in the sea cucumber Holothuria glabberrima by describing the spatial and temporal pattern of cellular events that occur during intestine regeneration following chemically induced evisceration. Regeneration begins as a thickening of the mesenteries that supported the autotomized organs to the body wall. The mesenterial thickening consists of tissues where most of the cellular populations found in the normal intestine are already present. However, the cell numbers differ, particularly those of hemocytes and amoebocytes, suggesting that some of these cells play an important role in the formation of the solid rod of hypertrophic mesentery that characterizes the intestinal primordia. The appearance of the luminal epithelium, together with the formation of the lumen, occurs during the second week of regeneration by proliferation and extensive migration of cells from the esophagus and cloacal ends into the thickenings. At this stage all tissue layers are present, but it takes an additional week for them to exhibit the proportions typical of the normal organ. Cell division, as determined by BrdU labeling, mainly occurs in the coelomic epithelia of the hypertrophic mesentery and in the regenerating luminal epithelium. Our study provides evidence that the process of new organ formation in holothurians can be described as an intermediate process showing characteristics of both epimorphic and morphallactic phenomena. 相似文献
33.
F Vilanova E Santacana V García JM Villar-Landeira 《Canadian Metallurgical Quarterly》1994,41(4):205-208
OBJECTIVES: To determine the efficacy and complications of continuous epidural perfusion of bupivacaine, adrenaline and fentanyl in the relief of pain during first and second stage labour during vaginal birth. PATIENTS AND METHODS: Between January 1990 and March 1993 we used continuous epidural perfusion for control of pain during labor in 1307 women. The solution administered through an epidural catheter and maintained until expulsion was one 10 ml bolus of bupivacaine 0.25% with adrenaline 1:200,000 and fentanyl 25 micrograms followed by continuous perfusion of bupivacaine 0.0625% with adrenaline 1:200,000 and fentanyl 2 micrograms/ml at an infusion rate of 12 ml/h. When analgesia was insufficient, a bolus of local anesthetic was administered or a pudendal block was carried out. RESULTS: Ninety-two percent of the birthing women reported good analgesic effect during the first stage; for 7% the effect was fair and for 0.55% it was poor. During the second stage 88% reported satisfactory analgesia, and 8% fair or poor. Assessment was not possible for the remaining women, who underwent cesarean sections. Complications were few and easily controllable. CONCLUSIONS: Maintenance of epidural perfusion with 0.0625% bupivacaine with adrenaline 1:200,000 and fentanyl 2 micrograms/ml provides sufficient analgesia during all stages of childbirth. 相似文献
34.
L Bravo RJ Monté V Alfonso N Cabrera M Gómez R Hernández B García 《Canadian Metallurgical Quarterly》1995,47(3):215-216
One hundred and fifty-five strains of Aeromonas isolated in the stools of children under 5 years presenting with acute diarrheal disease were studied. Using the Aerokey II system for the identification of species, 47 strains were identified as Aeromonas caviae, 58 as Aeromonas hydrophila, 23 as Aeromonas veronii biovar sobria, 14 as Aeromonas trota, 9 as Aeromonas veronii biovar veronii, 2 as Aeromonas jandaei and 2 as Aeromonas shubertii, Emphasis is placed on the advantages of this method which allowed for the classification of new species not identified previously in our country. 相似文献
35.
Rodríguez-de-Vera Jesús M. González-Carrillo Josefa García José M. Bernabé Gregorio 《The Journal of supercomputing》2021,77(9):10138-10151
The Journal of Supercomputing - Left ventricular non-compaction (LVNC) is a rare cardiomyopathy characterized by abnormal trabeculations in the left ventricle cavity. Although traditional computer... 相似文献
36.
Moutafis Panagiotis García-García Francisco Mavrommatis George Vassilakopoulos Michael Corral Antonio Iribarne Luis 《Distributed and Parallel Databases》2021,39(3):733-784
Distributed and Parallel Databases - Given two datasets of points (called Query and Training), the Group (K) Nearest-Neighbor (GKNN) query retrieves (K) points of the Training with the smallest sum... 相似文献
37.
Software Quality Journal - Energy consumption of software has been becoming increasingly significant, since it can vary according to how the software has been developed. In recent years, developers... 相似文献
38.
The partitioning of total dissectible body fat and the amounts of intramuscular fat in Psoas major, Semitendinosus and Biceps brachii muscles were determined in two groups of A. Angus and AA × Nelore steers with similar averages of total dissectible fat (27·7 kg). In addition, the fatty acid composition of total fat and the triglyceride fraction from dissectible and intramuscular fats were determined.
The AA × Nelore steers have higher levels of subcutaneous fat and lower levels of intermuscular fat than the A. Angus but contain lower levels of intramuscular fat in the three muscles. The allometric regressions varied according to the muscle and breed type. The fatty acid composition of subcutaneous and kidney fats were similar but differences in the percentages of 14:0, 18:0, 18:2 and 20:4 fatty acids in intramuscular fats between the two genetic groups were detected. 相似文献
39.
C García Barroso R Cela Torrijos J A Pérez-Bustamante 《Zeitschrift für Lebensmittel-Untersuchung und -Forschung》1987,185(4):307-314
The different groups and/or classes among phenolic acids and aldehydes identified during the elaboration process of "fino" sherry wine have been studied. The study was carried out using different processes during the elaboration of the wine and we have attempted to establish whether the different treatments of the grape affect these groupings. The study was undertaken by means of cluster and multifactorial analysis on the data obtained by the quantitative determination of phenolic acids and aldehydes during vinification and in experiments carried out on the grape under different mechanical treatments. The analysis of phenolic acids and aldehydes was done with HPLC, using a C-18 mu-Bondapak and a stepwise composite gradient. The samples were previously extracted with ethylic ether. 相似文献
40.
Andrés García Higuera Javier de las Morenas 《Journal of Intelligent Manufacturing》2014,25(5):1197-1206
Traditional management and control models can benefit from added levels of intelligence to increase their capability to adapt to the continuous changes in global markets. After reviewing the classical definition of intelligence and its levels, this paper provides a new approach to help increase the responsiveness of management and control to changes and disturbances in the manufacturing supply chain. The ancient concept of the “Tertium Quid” has inspired a three-level community of agents (MAS-TRIO) that is proposed to improve the coordination of all actors involved. The proposed model combines Multi-Agent Systems (MAS) with Radio-Frequency Identification (RFID) to make possible a certain level of Autonomous Intelligence in the decision-taking process. This paper analyses how these levels of intelligence can be applied to management and control, and the performance of the proposed model has been tested at low and mid-levels on an experimental platform representing the facilities of a distribution centre controlled by a network of programmable logic controllers (PLCs). 相似文献