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81.
INTRODUCTION: The primary lymphoma of the central nervous system are between 1 to 2% of all the brain tumors. The most important risk factor for the development of this kind of lesions is both acquired and congenital immunologic deficiency. METHODS AND RESULTS: In this paper we'll try to study the 13 cases of primary lymphomas of the central nervous system from etiological, epidemiological, clinic, diagnostic, therapeutic and outcome point of view. CONCLUSION: Besides we will discuss the bibliography founded paying special attention to diagnostic and therapeutic features. 相似文献
82.
JC López Pacios L Parra Muntaner MC Pi?eiro Fernández SC Gómez Cisneros E Sánchez Sánchez JA Rivas Escudero FJ Madrid García J García Alonso 《Canadian Metallurgical Quarterly》1998,51(4):331-333
The occurrence of secondary hypogonadism is a common finding in males who seek help with erectile dysfunction, although the relationship to diminished testosterone is unclear. Two possibilities exist regarding both the genesis and maintenance of the hypogonadotropic hypogonadal state. First, a defect in hypothalamic function, resulting in downregulation as well as in alterations of anterior pituitary function; second, estradiol inhibition of gonadotropin release, both of which result in decreased testosterone production. As testosterone levels decrease and estradiol levels increase, the ratio of free testosterone to estradiol reaches a critical point and the estrogenic gonadotropin suppressive effects predominate. This ratio may signal the biological point of no return and could become one of the criteria for defining the separation of the transitional hypogonadal state from the final 'end stage' hypogonadotropic hypogonadal state. As the aging process continues, there is a relative accumulation of fatty tissue, and aromatization accelerates the conversion of testosterone to estradiol. This additional secondary estradiol inhibition results in the maintenance of the testosterone deficient state, and the aging process continues uncontested. 相似文献
83.
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
84.
85.
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
86.
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
87.
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
88.
Hobbie KA Peterson ES Barton ML Waters KM Anderson KA 《Journal of laboratory automation》2012,17(4):275-283
Large collaborative centers are a common model for accomplishing integrated environmental health research. These centers often include various types of scientific domains (e.g., chemistry, biology, bioinformatics) that are integrated to solve some of the nation's key economic or public health concerns. The Superfund Research Center (SRP) at Oregon State University (OSU) is one such center established in 2008 to study the emerging health risks of polycyclic aromatic hydrocarbons while using new technologies both in the field and laboratory. With outside collaboration at remote institutions, success for the center as a whole depends on the ability to effectively integrate data across all research projects and support cores. Therefore, the OSU SRP center developed a system that integrates environmental monitoring data with analytical chemistry data and downstream bioinformatics and statistics to enable complete "source-to-outcome" data modeling and information management. This article describes the development of this integrated information management system that includes commercial software for operational laboratory management and sample management in addition to open-source custom-built software for bioinformatics and experimental data management. 相似文献
89.
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
90.
Palomares Iván Martínez-Cámara Eugenio Montes Rosana García-Moral Pablo Chiachio Manuel Chiachio Juan Alonso Sergio Melero Francisco J. Molina Daniel Fernández Bárbara Moral Cristina Marchena Rosario de Vargas Javier Pérez Herrera Francisco 《Applied Intelligence》2021,51(9):6497-6527
Applied Intelligence - The17 Sustainable Development Goals (SDGs) established by the United Nations Agenda 2030 constitute a global blueprint agenda and instrument for peace and prosperity... 相似文献