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31.
The assessment of blood damage and of the activation of the coagulation, complement and/or inflammatory systems by cardiovascular and extracorporeal devices is difficult at best. Immunoassay methods are now available for the measurement of many of the proteins, enzymes and peptides involved in coagulation, thrombosis, complement and inflammation. We present a long-range project and plan to develop an array of remote, on-line, semicontinuous immunosensors for selected coagulation proteins, based on fluoroimmunoassay principles. The free/bound separation step is performed optically. Excitation of fluorescence is performed via an evanescent wave produced by total internal reflection and waveguide optics. Fluorescence emission is collected only in the near field. Means to deliver fluorescently-labelled reagent and to modify the antigen-antibody binding constant are presented and discussed. The results of non-specific binding, plasma-blood fluorescence, and blood compatibility are also discussed. 相似文献
32.
Claudio Gustavo Stefanoff Rocío Hassan Ana Carolina Gonzalez Luiz Ant?nio B Andrade Daniel G Tabak Sérgio Romano Ilana R Zalcberg 《Diagnostic molecular pathology》2003,12(2):79-87
We herein present a technical strategy to optimize DNA isolation from paraffin-embedded tissue (PET). This includes the choice of adequate buffers for proteinase K digestion and multiplex PCR amplifications for assessing the appropriateness of DNA extracts for subsequent PCR assays for detecting clonality. We found that the association of proteinase K digestion in nonionic buffer and subsequent extract dilutions accounted for 79% of successful amplifications. A final efficiency of 88% was achieved by additional organic extractions and/or re-extractions. Comparisons were carried out with control DNA extracts from fresh samples to assess the efficiency of each clonality assay. Immunoglobulin CDRIII rearranged region amplification was more efficient for pregerminal center B-cell lymphomas in contrast to CDRII rearrangement detection, which was more effective for germinal and postgerminal lymphomas. T-cell clonality detection by TCRgamma PCR was less efficient in PET samples than in fresh tissues showing that DNA integrity is more critical for TCR than for IGH amplification. Two inconclusive cases without phenotypic markers and two other atypical lymphoproliferations masked by reactive T cells were diagnosed as plasmablastic lymphomas and as monoclonal B-proliferations, respectively, due to IGH rearrangements. 相似文献
33.
34.
Functional consequences of ROMK mutants linked to antenatal Bartter's syndrome and implications for treatment 总被引:4,自引:0,他引:4
The antenatal variant of Bartter's syndrome is an autosomal recessive
kidney disease characterized by polyhydramnios, premature delivery,
hypokalemic alkalosis and hypercalciuria. It is genetically heterogeneous,
having been linked recently to mutations in an ATP- sensitive, renal outer
medullary K+channel, ROMK, and earlier to mutations in the Na-K-2Cl
co-transporter, NKCC2. We characterized four of the mutations reported in
three heterozygous ROMK variants of antenatal Bartter's and found that each
expressed a distinct phenotype in Sf9 cells. One mutation expressed normal
function and appears to be an allelic polymorphism. The other three
mutations produced channels with significantly reduced K+fluxes. However,
the mechanisms in each case were different and reflected abnormalities in
phosphorylation, proteolytic processing or protein trafficking. The
different mechanisms may be important in the design of appropriate therapy
for patients with this disease.
相似文献
35.
Determination of the parent of origin in nine cases of prenatally detected chromosome aberrations found after intracytoplasmic sperm injection 总被引:1,自引:17,他引:1
Van Opstal D; Los FJ; Ramlakhan S; Van Hemel JO; Van Den Ouweland AM; Brandenburg H; Pieters MH; Verhoeff A; Vermeer MC; Dhont M; In't Veld PA 《Human reproduction (Oxford, England)》1997,12(4):682-686
Prenatal cytogenetic analysis of 71 fetuses conceived by intracytoplasmic
sperm injection (ICSI) resulted in the detection of nine (12.7%) chromosome
aberrations including two cases of 47,XXY, four cases involving a 45,X cell
line and three autosomal trisomies. Molecular analysis of the parental
origin of the deleted or supernumerary chromosome was performed by using
polymorphic microsatellite markers. Six cases involving a sex chromosome
abnormality were found to be of paternal origin while the two trisomic
cases that could be analysed were of maternal origin. Two cases involved
the same infertile couple who had two consecutive ICSI pregnancies
terminated because of a chromosome abnormality. The replaced embryos in
both cases originated from a single batch of ICSI fertilized oocytes of
which part was used to initiate the first pregnancy and part was
cryopreserved and used to initiate the second pregnancy.
相似文献
36.
37.
KM Kanal NJ Hangiandreou AM Sykes HE Eklund PA Araoz JA Leon BJ Erickson 《Journal of digital imaging》2002,14(1):30-37
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's
gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing
radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers,
and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed
with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant,
and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender
were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women
was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative
English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and
while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology
practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient
way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed
and sensitive manner. 相似文献
38.
Nascimento Bruno Andrade Hiury S. Miranda Eduardo P. Barbosa João Arthur Brunhara Alves Moscardi Paulo R. Arap Marco A. Mitre Anuar I. Srougi Miguel Srougi Victor Duarte Ricardo J. 《International urology and nephrology》2021,53(2):269-273
International Urology and Nephrology - To evaluate outcomes of laparoscopic pyeloplasty (LP) in adults with poorly functioning kidney due to ureteropelvic junction obstruction (UPJO). A... 相似文献
39.
40.
Andrade C Muñoz D Koukoulis A Martínez Cueto P Gómez-Alonso J 《Neurología (Barcelona, Spain)》1999,14(3):131-134
Mycoplasma pneumoniae infections usually produce respiratory symptoms, that only exceptionally involve the nervous system. In this case, the infection generally causes an encephalitic picture characterized by impaired consciousness and seizures, and by normal or non-specific neuroradiological findings. However, four cases of M. pneumoniae infection associated with symmetrical lesions in the putamen and its external surrounding areas, and with extrapiramidal symptoms, have been recently published. We present the case of a patient with a clinical picture characterized by confusion, fever, and seizures, associated with a M. pneumoniae infection. The MRI study showed two symmetrical lesions that involved the areas just outside the putamen and disappeared coinciding with her clinical improvement. The present case would support that the encephalopathy associated with the M. pneumoniae infection shows a tendency to involve a particular region of the brain. Our case might represent the minimal expression of these characteristic lesions, which in the most benign cases would involve the areas immediately outside the putamen, and in other instances the putamen as well. 相似文献