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81.
82.
Anthony J McGoron Michael Capille Michael F Georgiou Pablo Sanchez Juan Solano Manuel Gonzalez-Brito John W Kuluz 《BMC medical imaging》2008,8(1):4
Background
Assessment of cerebral blood flow (CBF) by SPECT could be important in the management of patients with severe traumatic brain injury (TBI) because changes in regional CBF can affect outcome by promoting edema formation and intracranial pressure elevation (with cerebral hyperemia), or by causing secondary ischemic injury including post-traumatic stroke. The purpose of this study was to establish an improved method for evaluating regional CBF changes after TBI in piglets. 相似文献83.
To gain insights into the composition of the B cell repertoire, we have investigated VH gene family expression associated with individual light chains. For this purpose, we have examined the use of 12 VH gene families in a large collection of hybridomas expressing one of the four lambda light chains [lambda 1 (V1J1), lambda 2 (V2J2 and V x J2) and lambda 3 (V1J3)]. Our results show that the distribution of the VH families is very different from one lambda subtype to another. This suggests that a few substitutions between VL regions are sufficient to generate very different associated repertoires by strong selection mechanisms. Moreover, we assume that the global VH expression pattern is not random but rather composed of many preferential VH/VL associations. 相似文献
84.
J Benitez C Martinez Frejo C Toledo J Sanchez Fayos C Ramos 《Cancer Genetics and Cytogenetics》1987,26(2):199-207
Serial cytogenetic studies have been performed in four patients with myelodysplastic syndromes. In all four a 5q- alteration was present, but with a different pattern of presentation. One patient presented 5q- as the only alteration since diagnosis; two patients acquired this alteration during the course of the disease; and the fourth showed a 5q- plus other alterations since the first cytogenetic study. Likewise, three of the four patients showed a clone with trisomy 8 and without 5q-. According to these observations and others from the literature with similar cytogenetic behavior, we have analyzed the following points: 5q- as a primary event and as the only alteration, 5q- as a secondary event, 5q- plus other alterations, and presence of cytogenetically different clones. Analysis of these points suggests that the 5q- alteration can represent an early mutation conferring a slow capacity of expansion to the affected clones, with the possibility of cytogenetic evolution during the progression of the disease (about 30% of the patients). Likewise, the association of trisomy 8 clones with 5q- clones can be a nonrandom event. 相似文献
85.
A novel missense mutation in exon 3 of the COL4A5 gene associated with late-onset Alport syndrome 总被引:1,自引:0,他引:1
Alberto E. Turco Sandro Rossetti M. Olivia Biasi Gianfranco Rizzoni Laura Massella Niina H. Saarinen Allessandra Renieri Pier Franco Pignatti Mario De Marchi 《Clinical genetics》1995,48(5):261-263
We have identified a novel missense transition (362G→A) in exon 3 of the COL4A5 gene in a male patient with late-onset Alport syndrome. We used non-isotopic single strand conformation polymorphism, heteroduplex analysis, and automated DNA sequencing. The mutation changes a conserved glycine at codon 54 for an aspartic acid (Gly54Asp), which abolishes a BstNI site. Using restriction analysis, we identified the heterozygous carrier status in the two daughters of the proband. Our findings are in keeping with the hypothesis that slower progressive forms of Alport syndrome are more often associated with missense mutations rather than large deletions or frameshifts. This is the first mutation described in the N-terminus triple helical 7S domain of the COL4A5 gene in an Alport syndrome patient. 相似文献
86.
Henriques C Sanchez MA Tryon R Landfear SM 《Molecular and biochemical parasitology》2003,130(2):101-110
African trypanosomes are unable to synthesize purines and depend upon purine nucleoside and nucleobase transporters to salvage these compounds from their hosts. To understand the crucial role of purine salvage in the survival of these parasites, a central objective is to identify and characterize all of the purine permeases that mediate uptake of these essential nutrients. We have cloned and functionally expressed in a purine nucleobase transport deficient strain of Saccharomyces cerevisiae a novel nucleobase transporter gene, TbNT8.1, from Trypanosoma brucei. The permease encoded by this gene mediates the uptake of hypoxanthine, adenine, guanine, and xanthine with Kms in the low micromolar range. The TbNT8.1 protein is a member of the equilibrative nucleoside transporter (ENT) family of permeases that occur in organisms as diverse as protozoa and mammals. TbNT8.1 is distinct from other ENT permeases that have been identified in trypanosomes in utilizing multiple purine nucleobases, rather than purine nucleosides, as substrates and is hence the first bona fide nucleobase permease identified in these parasites. Furthermore, unlike the mRNAs for other purine transporters, TbNT8.1 mRNA is significantly more abundant in insect stage procyclic forms than in mammalian stage bloodstream forms, and the TbNT8.1 permease thus may represent a major route for purine nucleobase uptake in procyclic trypanosomes. 相似文献
87.
E G Sanchez 《Southern medical journal》1987,80(2):223-227
The DSM-III diagnostic criteria for schizophreniform disorder, mainly based on duration of symptoms, are insufficient to furnish a good treatment strategy. In recent literature, schizophreniform disorder has been grouped either with the schizophrenias or with the affective disorders. Scandinavian researchers have described two other groups of psychotic disorders that resemble schizophreniform disorder. These are the reactive psychosis and the cycloid psychosis. They were found to be different from the schizophrenias and the affective disorders. "Good prognosis" schizophrenia, which has been extensively studied and reported in the literature, is clinically very similar to schizophreniform disorder. The relatively consistent data collected in patients with good prognosis schizophrenia may provide the basis for the additional diagnostic criteria needed in DSM-III schizophreniform disorder. 相似文献
88.
H. A. Kolnick Jennifer E. Miller Olivia Dupree Lisa Gualtieri 《Online Journal of Public Health Informatics》2021,13(1)
How might clinicians collect the vitals needed for effective scheduled video visits for older adults? This challenge was presented by AARP to graduate students in a Digital Health course at Tufts University School of Medicine. The design thinking process was used to create a product that would meet this need, keeping the needs and constraints of older adults, especially those with chronic conditions or other barriers to health, central to the solution. The initial steps involved understanding and empathizing with the target audience through interviews and by developing personas and scenarios that identified barriers and opportunities. The later steps were to ideate potential solutions, design a prototype, and define product success. The design thinking process led to the design of Home Health Hub, a remote patient monitoring (RPM) platform designed to meet the unique needs of older adults. Additionally, Home Health Hub can conceivably benefit all users of telehealth, regardless of health status—an important need during the COVID-19 pandemic, and in general due to increased use of virtual visits. Home Health Hub is one example of what can be achieved with the dedicated use of design thinking. The design thinking process can benefit public health practice as a whole by encouraging practitioners to delve into a problem to find the root causes and empathize with the needs and constraints of stakeholders to design innovative, human-centered solutions. 相似文献
89.
90.
Grazieli Maboni Jessica A. Elbert Justin M. Stilwell Susan Sanchez 《Emerging infectious diseases》2021,27(3):979
Severe nasal Prototheca cutis infection was diagnosed postmortem for an immunocompetent cat with respiratory signs. Pathologic examination and whole-genome sequencing identified this species of algae, and susceptibility testing determined antimicrobial resistance patterns. P. cutis infection should be a differential diagnosis for soft tissue infections of mammals. 相似文献