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11.
The significance of anticardiolipin antibodies (ACAs) prior to renal transplantation is unclear. We studied a cohort of 337 patients who underwent renal transplantation from 1996 to 2001. Follow-up continued until allograft loss, patient death or 31 December 2002. The primary outcome was a composite endpoint of death-censored allograft loss or a 25% reduction in estimated glomerular filtration rate (GFR) from 1-month post-transplant. Secondary outcomes were allograft loss, a 25% reduction in GFR, acute rejection and creatinine at 1 year. IgG and IgM ACA titers were positive (> or =15) in 18.1% of recipients. There were no significant differences at baseline between recipients, except coumadin therapy in those with positive ACA titers (20% vs. 7.4%). Post-transplant, there was no increase in the primary outcome in ACA-positive patients, even after adjustment for anticoagulation with coumadin (HR = 1.42 [0.68, 2.96]). There was no difference in secondary outcomes between those with or without positive titers. Two of five patients with very high titers (>50) who were not anticoagulated had early graft loss. A positive ACA titer prior to kidney transplantation was not associated with inferior renal outcomes after transplantation, although more research is required to address the prognostic significance of very high ACA titers.  相似文献   
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The anisakid nematode populations collected from fish and stranded cetaceans along from Iberian Peninsula waters were morphologically identified as corresponding to the Anisakis simplex complex. In order to realise their molecular identification and to analyse the extent of genetic variation, the entire ITS (ITS1, 5.8S rDNA gene and ITS2) and the mitochondrial small subunit of rRNA were pcr-amplified and sequenced. Digestions of the amplified its region with HinfI and HhaI allowed the identification of three different genotypes, belonging to A. simplex s.s., A. pegreffii and a yet not described recombinant genotype. The ITS sequences of the recombinant genotypes showed the presence of heterozygotes C/T at position 240 and 256 of the aligned sequence. Otherwise, the analysis of mtDNA sequences showed the existence of a different parental origin for recombinant genotypes. In order to check if they can be the products of a polymorphism normally occurring both in A. pegreffii and in A. simplex s.s., and/or the existence of an incomplete concerted evolution, three samples were also collected as controls in isolated geographic areas, where sympatric coexistence between A. simplex s.s. and A. pegreffii does not occur. The results supports the hypothesis that the recombinant individuals may be a product of interspecific hybridisation, and describe the Iberian Peninsula waters as a hybrid zone for the two sibling species.  相似文献   
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Chitambar  CR; Zivkovic  Z 《Blood》1989,74(2):602-608
Information regarding transferrin (Tf) receptor degradation is largely incomplete. HL60 cells were shown to release to their growth medium a Tf-binding protein which could be immunoprecipitated by anti-Tf receptor monoclonal antibodies (MoAbs) B3/25 and OKT9. Soluble Tf receptor was detected in the medium within one hour of replating of cells, and its release was inhibited at 4 degrees C. The affinity of Tf for the soluble receptor released by cells (kd = 2.3 x 10(-10) mol/L) was slightly lower than its affinity for the detergent-solubilized cellular receptor (kd = 1.2 x 10(-10) mol/L). 125I-Tf internalized and released by cells subsequently bound to Tf receptor released by the same cells, and soluble Tf receptor in the conditioned medium (CM) inhibited 125I-Tf binding to intact cells. The soluble Tf receptor isolated from the CM was smaller (78,000 daltons) than the cell surface receptor (94,000 daltons) when analyzed by gel electrophoresis under reducing conditions. Isolated cell membranes readily released soluble receptor; however, this release could be blocked by protease inhibitors. The soluble Tf receptor may represent the extracytoplasmic domain of the cellular Tf receptor released from the surface of HL60 cells through proteolytic cleavage by a membrane-based protease.  相似文献   
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BACKGROUND: This is to describe a restricted sensory syndrome of unique distribution due to thalamic infarct. CASE DESCRIPTION: We report a case of pure sensory disturbance involving the left intraoral and perioral regions and the tips of the thumb and forefinger of the left hand. Magnetic resonance imaging revealed a small infarct in the contralateral thalamus, presumably affecting the nucleus ventralis posterior. CONCLUSIONS: This patient provides an excellent correlation between clinical findings and thalamic representation of body surface as established during stereotactic procedures.  相似文献   
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The pattern of pre- and postnatal appearance of 5-HT1D receptors throughout the different areas of the human brain was studied by quantitative in vitro autoradiography, using [125I]GTI (serotonin O -carboxymethyl-glycyl-[125I]tyrosinamide) as a ligand. The anatomical distribution of 5-HT1D receptors in neonatal, infant and children's brain was in good agreement with that observed in the adult, the basal ganglia and substantia nigra being the most intensely labelled areas. The development of these receptors throughout the human brain was mainly postnatal: low densities of [125I]GTI binding sites were observed at the fetal/neonatal stage in most regions analyzed, in contrast with the high levels of labelling found in infant and children's brains. Indeed, in a number of regions, including the globus pallidus, substantia nigra and visual cortex, a peak of overexpression of 5-HT1D receptors was observed in the first decade of life. Such overexpression could support a regulatory role for 5-HT1D receptors in advanced periods of the CNS developmental process. Our results also indicate that the administration of drugs acting on 5-HT1D receptors during the early postnatal period of life could result in modifications of their properties, as these receptors are already functional in this period.  相似文献   
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Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm).  相似文献   
19.
Within Mexico's floristic abundance, plants with curative properties are outstanding due to their popularity in handling several illnesses, a fact that becomes specially important for the social groups of the tropical regions. In this paper the results of an ethnobotanical study carried out in 57 rural populations from the Mexican states of Oaxaca, Veracruz and Puebla are presented; questionnaire and interview methods were applied, with special attention to the use of plants for medical purposes. The most relevant results were: the taxonomic determination of 237 vegetal species from which 399 curative products are obtained, in order to combat 57 illnesses, the most frequent of which are those related to the digestive system, the skin, the reproductive system and those of supernatural origin, which can only be treated by the use of plants in special ceremonies known as 'limpias', due to their peculiar condition.  相似文献   
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