Abstract：
BACKGROUND:Molecular analysis of plasma DNA during human pregnancy has led to the discovery that maternal plasma contains both fetal and maternal DNA. This valuable source of fetal DNA opens up new possibilities for noninvasive prenatal diagnosis. APPROACH:Published data from the last 3 years demonstrating the feasibility and utility of analyzing fetal DNA in maternal plasma are reviewed. CONTENT:The detection of fetal DNA in maternal plasma is much simpler and more robust than detecting fetal nucleated cells in maternal blood, and does not require prior enrichment. This approach has been shown to have application in the prenatal diagnosis of fetal rhesus D status, sex-linked disorders, and other paternally inherited genetic disorders. Abnormal fetal DNA concentrations in maternal plasma and serum have been found in common pregnancy-associated disorders, including preterm labor and preeclampsia, as well as in pregnancies complicated by fetal trisomy 21. After delivery, fetal DNA is cleared rapidly from maternal plasma, with a half-life in the order of minutes. These clearance kinetics exhibit an important difference from fetal cell clearance, where long-term persistence has been demonstrated. SUMMARY:It has been only 3 years since fetal DNA was first detected in maternal plasma, and much remains to be learned about the biology of this phenomenon. In addition, additional diagnostic applications beyond those discussed here can be expected in the near future.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Lo YMsubject
Has Abstractpub_date
2000-12-01 00:00:00pages
1903-6issue
12eissn
0009-9147issn
1530-8561journal_volume
46pub_type
杂志文章,评审abstract：:Published estimates of the imprecision characteristics of immunoassays are often based on quantities of data that seem to be inadequate. The increasing use of imprecision profiles has not necessarily improved the situation. We describe and illustrate a method of computing 95% confidence intervals for profiles estimate...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-07-01 00:00:00
abstract：BACKGROUND:Recent reports have described inherent problems with androgen immunoassays compared with mass spectrometry analyses. METHODS:We developed a method for measuring serum testosterone (T) and 5alpha-dihydrotestosterone (DHT) simultaneously via liquid-liquid extraction followed by liquid chromatography-tandem ma...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.103846
更新日期：2008-11-01 00:00:00
abstract：BACKGROUND:Concerns exist regarding how the 99th percentile upper reference limit (URL) of cardiac troponin (cTn) is determined and whether it should be derived from normal healthy individuals. CONTENT:The 99th percentile URL of cTn is an important criterion to standardize the diagnosis of myocardial infarction (MI) f...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1093/clinchem/hvaa158
更新日期：2020-09-01 00:00:00
abstract：BACKGROUND:We evaluated assays to measure both total tissue plasminogen activator (tPA) and the three principle forms of tPA in plasma: active tPA, tPA complexed with plasminogen activator inhibitor type 1 (PAI-1), and tPA complexed with C1-inhibitor. METHODS:Active tPA was measured by use of an indirect amidolytic as...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2000-01-01 00:00:00
abstract：BACKGROUND:An association has been described between mortality in children with meningococcal disease and functional polymorphisms in the interleukin-1 (IL1) cluster. We undertook a multicenter study to evaluate associations of these polymorphisms in a Central European population. PATIENTS AND METHODS:The study involv...
journal_title：Clinical chemistry
pub_type： 杂志文章,多中心研究
doi：10.1373/clinchem.2005.058537
更新日期：2006-03-01 00:00:00
abstract：BACKGROUND:Cross-sectional studies have reported seasonal variation in high-sensitivity C-reactive protein (hsCRP). However, longitudinal data are lacking. METHODS:We collected data on diet, physical activity, psychosocial factors, physiology, and anthropometric measurements from 534 healthy adults (mean age 48 years,...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.111245
更新日期：2009-02-01 00:00:00
abstract：:The concentrations of 25 plasma proteins were measured in 22 patients with membranous nephropathy. For some large proteins, the plasma concentrations were increased; there were also large proteins with low plasma concentrations, but small or medium-sized proteins showed uniformly lower plasma concentration than the co...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1997-07-01 00:00:00
abstract：BACKGROUND:Cleavage of conjugates is an important step in toxicological analysis, especially of urine samples. The aim of this study was to combine the advantages and to reduce the disadvantages of acid hydrolysis and conventional enzymatic hydrolysis procedures. METHODS:beta-Glucuronidase (GRD; EC 3.2.1.31) and aryls...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1999-12-01 00:00:00
abstract：:This article reviews key advances in ion-selective electrode technology that have made potentiometric measurements of ionized calcium (Ca2+) reliable and precise. Our use of two second-generation Ca2+ analyzers (Radiometer ICA1 and NOVA 8) made possible uninterrupted service as volume increased to 31 640 patient tests...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1986-08-01 00:00:00
abstract：:To investigate the use of streptavidin-hapten derivatives as potential protein-tracer conjugates for competitive-type immunoassays, we labeled streptavidin with cortisol and compared biotin-binding activity of the conjugates with that of unlabeled streptavidin. In this model system, streptavidin labeled with one to ap...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1991-01-01 00:00:00
abstract：:A rapid and precise immunoassay for quantification of total homocysteine in blood samples is presented. The method avoids the use of radioisotopes and chromatographic separations and relies on enzymatic conversion of homocysteine to S-adenosyl-L-homocysteine, followed by quantification of S-adenosyl-L-homocysteine by ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1998-02-01 00:00:00
abstract：:We present a statistical interpretation of plasma (Pl) and (or) erythrocyte (Erc) concentrations of magnesium, zinc, calcium, potassium, and total high-density lipoprotein (HDL) cholesterol, as well as of the activity of total creatine kinase (CK) and its CK-MB isoenzyme, in 26 men with pre-infarction syndrome (PIS) a...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-05-01 00:00:00
abstract：BACKGROUND:Hyperhomocysteinemia (HHcy) has been linked to impaired left ventricular function and clinical class in patients with chronic heart failure. We hypothesized that HHcy stimulates myocardial brain natriuretic peptide (BNP) expression and induces adverse left ventricular remodeling. METHODS:We randomized 50 ra...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2006.077859
更新日期：2007-04-01 00:00:00
abstract：BACKGROUND:Data regarding the prognostic value of programmed cell death ligand 1 (PD-L1) expression on circulating tumor cells (CTCs) are lacking. However, CTCs could represent an alternative approach to serial biopsies, allowing real-time monitoring of cancer phenotype. METHODS:We evaluated, in a dedicated prospectiv...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1093/clinchem/hvaa121
更新日期：2020-08-01 00:00:00
abstract：:In the present clinical evaluation of Triage immunoassay for detection of drugs of abuse, we examined a possible connection between the laboratory skills of the personnel using it and the quality of analytical results; we also evaluated the degree of concordance between the Triage results and those obtained by an inst...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1996-09-01 00:00:00
abstract：BACKGROUND:An accurate determination of the major HFE mutation (C282Y), which is associated with hereditary hemochromatosis, is important in diagnosis and risk assessment for this disease. We report a single-tube high-throughput PCR method for the detection of C282Y. METHODS:We combined three previously described prin...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2000-10-01 00:00:00
abstract：:Peroxidation of lipids is believed to play a key role in various degenerative diseases. However, few simple tests are able to detect individual susceptibility or resistance to peroxidation. Measurement of the basal concentrations of lipid peroxides in plasma is not satisfactory because they are so low. Therefore, we d...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1991-10-01 00:00:00
abstract：:During phase I/II clinical trials of sirolimus (rapamycin; SRL), therapeutic drug monitoring was performed with a multistep liquid-liquid extraction of 1-mL aliquots of whole blood followed by reversed-phase HPLC with ultraviolet detection. Blood was sampled according to a standardized protocol and clinical status. SR...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1996-12-01 00:00:00
abstract：:Carbohydrate-deficient transferrin (CDT) may now be the most valuable biological marker for diagnosis of alcohol abuse. We compared the diagnostic performance of two new CDT tests, Axis %CDT turbidimetric immunoassay (TIA) and Axis %CDT HPLC, against Specialty Laboratories' isoelectric focusing/immunoblotting/laser de...
journal_title：Clinical chemistry
pub_type： 临床试验,杂志文章
doi：
更新日期：1997-06-01 00:00:00
abstract：BACKGROUND:Detection of melanoma cells in circulation may be important in assessing tumor progression. The objective of this study was to develop a specific, reliable multimarker quantitative real-time reverse transcription-PCR (qRT) assay for detecting melanoma cells in patients' blood. METHODS:We developed qRT assay...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2004.045096
更新日期：2005-06-01 00:00:00
abstract：:alpha 1-Antitrypsin (A1AT) deficiency is a relatively common autosomal recessive disease, resulting most often from a single base pair (1 bp) substitution called the Z mutation. Previous genetic tests for carriers and affected patients have relied on quantitative binding of radioactive probes to an amplified gene prod...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-08-01 00:00:00
abstract：:Advanced glycosylation end products (AGEs) are thought to play an important role in the development of diabetic complications. Oxidative reactions are essential for the formation of some AGEs, termed glycoxidation products. Increased concentrations of pentosidine, one of such products, are found in tissue and serum in...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1998-02-01 00:00:00
abstract：BACKGROUND:Distinguishing adenocarcinoma and squamous cell carcinoma subtypes of non-small cell lung cancers is critical to patient care. Preoperative minimally-invasive biopsy techniques, such as fine needle aspiration (FNA), are increasingly used for lung cancer diagnosis and subtyping. Yet, histologic distinction of...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1093/clinchem/hvaa207
更新日期：2020-11-01 00:00:00
abstract：:Methods are described for detection of lactate dehydrogenase (LDH) inhibitors in preparations of reduced nicotinamide adenine dinucleotide. They are (a) comparison of values by kinetic methods with those measured for highly purified NADH and (b) examination of Lineweaver-Burk plots. Chromatographic inhomogeneities are...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-10-01 00:00:00
abstract：BACKGROUND:Endothelial nitric oxide synthase (eNOS) could be a candidate gene for coronary artery disease (CAD). This study investigated the relationship of the eNOS Glu(298)-->Asp and T(786)-->C polymorphisms with the presence and severity of CAD in the Italian population. METHODS:We enrolled 415 unrelated individual...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/49.3.389
更新日期：2003-03-01 00:00:00
abstract：:We describe a high-performance liquid chromatographic method for the quantitative determination of gentamicin in serum. The antibiotic was separated from serum by passage through a silicic acid column, derivatized with o-phthalaldehyde, and eluted with ethanol. The derivatized gentamicin was then separated into all th...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-12-01 00:00:00
abstract：BACKGROUND:It is important that cardiac troponin be measured accurately with a robust method to limit false results with potentially adverse clinical outcomes. In this study, we characterized the robustness of 4 analytical platforms by measuring the outlier rate between duplicate results. METHODS:We measured cardiac t...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2010.159830
更新日期：2011-05-01 00:00:00
abstract：BACKGROUND:Hepcidin-25 reduces iron absorption by binding to the intestinal iron transporter ferroportin and causing its degradation. Currently, little is known about the basal regulation of circulating hepcidin-25. In addition, although erythropoietin administration has been reported to decrease the circulating hepcid...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2012.186866
更新日期：2012-08-01 00:00:00
abstract：:The metabolism of the synthetic substrate 7-ethoxyresorufin is a selective measure of the activity of cytochrome P-448 monooxygenase, the subset of cytochrome P-450-mediated enzymes preferentially induced by polycyclic aromatic hydrocarbons and related compounds. 7-Ethoxycoumarin metabolism, on the other hand, reflect...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-09-01 00:00:00
abstract：:We report here the evaluation of the Abbott TDx assay with a monoclonal antibody for selectively quantifying cyclosporine (CsA) in whole blood. Over the clinically relevant concentration ranges, results with this assay demonstrated within- and between-run CVs of less than 2.5% and 5%, respectively; sensitivity of 25 m...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-11-01 00:00:00
