Abstract：
BACKGROUND:Analysis of fetal DNA in maternal plasma has recently been introduced as a new method for noninvasive prenatal diagnosis, particularly for the analysis of fetal genetic traits, which are absent from the maternal genome, e.g., RHD or Y-chromosome-specific sequences. To date, the analysis of other fetal genetic traits has been more problematic because of the overwhelming presence of maternal DNA sequences in the circulation. We examined whether different biochemical properties can be discerned between fetal and maternal circulatory DNA. METHODS:Plasma DNA was examined by agarose gel electrophoresis. The fractions of fetal and maternal DNA in size-fractionated fragments were assayed by real-time PCR. The determination of paternally and maternally inherited fetal genetic traits was examined by use of highly polymorphic chromosome-21-specific microsatellite markers. RESULTS:Size fractionation of circulatory DNA indicated that the major portion of cell-free fetal DNA had an approximate molecular size of <0.3 kb, whereas maternally derived sequences were, on average, considerably larger than 1 kb. Analysis of size-fractionated DNA (
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Li Y,Zimmermann B,Rusterholz C,Kang A,Holzgreve W,Hahn Sdoi
10.1373/clinchem.2003.029835subject
Has Abstractpub_date
2004-06-01 00:00:00pages
1002-11issue
6eissn
0009-9147issn
1530-8561pii
clinchem.2003.029835journal_volume
50pub_type
杂志文章abstract：:We describe an improved procedure for the preparation of plasma or serum for determination of theophylline by reverse phase high-performance liquid chromatography. Quantitative results are available in less than 30 min from receipt of sample. The chromatogram is complete in 8 to 16 min, which includes the use of an in...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-01-01 00:00:00
abstract：:This one-dimensional thin-layer chromatographic method is used for assay of phospholipids in the gastric aspirate of newborns. The solvent mixture (chloroform/hexane/methanol/glacial acetic acid/water, 12/7/4/3/0.3 by vol) completely resolves lecithin, sphingomyelin, phosphatidylinositol, phosphatidylserine, phosphati...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-04-01 00:00:00
abstract：:We present an improved fructosamine assay for use with the Technicon RA-1000 analyzer. Features of this assay include: specimen throughput of 100 per hour, within-batch CV of 1.5%, between-batch CV of 2.4%, standard curve linear up to 24.9 mmol of fructosamine per liter, and good correlation (r = 0.82) with hemoglobin...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1985-12-01 00:00:00
abstract：:We measured immunoglobulins in the sera of 33 patients on days 1, 3, 6, 10, and 17 and three to four weeks after surgical operations (mostly hysterectomy or appendectomy) or (six patients) after spinal injury. In the absence of infection or blood transfusion, IgG usually decreased slightly and transiently after hyster...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-05-01 00:00:00
abstract：:We compared serum lipoprotein cholesterol concentrations in a randomly selected subsample (n = 406) population of children (ages 5 to 17 years), as measured by the heparin-Ca2+ and the heparin-Mn2+ precipitation methods. Statistical analysis showed significant differences between results by these methods, especially i...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-10-01 00:00:00
abstract：:Autocorrelation of clinical chemistry quality-control (Q/C) measurements causes one of the basic assumptions underlying the use of Levey-Jennings control charts to be violated and performance to be degraded. This is the requirement that the observations be statistically independent. We present a proposal for a new app...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-07-01 00:00:00
abstract：:The fructosamine test is considered clinically useful for assessing short-term integrated control of blood glucose, but there are few published data to support this hypothesis. We fractionated glycated and nonglycated proteins by affinity chromatography on phenylboronate columns and, with specific immunochemical metho...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-10-01 00:00:00
abstract：:Using high-performance liquid chromatography and gas chromatography, we reevaluated the 24-h influence of a serotonin- and dopamine-rich diet on platelet serotonin and serotonin, 5-hydroxyindoleacetic acid (5-HIAA), and major catecholamine metabolites in the urine of 15 healthy adults. Although there were significant ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-09-01 00:00:00
abstract：:The apolipoprotein A-I (apo A-I) radioimmunoassay established in our laboratory involves use of purified apo A-I as the primary standard for quantifying apo A-I in plasma and a pooled plasma (quality-control sample) as a secondary standard to decrease interassay variation. The measured values for apo A-I increased ove...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-07-01 00:00:00
abstract：BACKGROUND:Cardiovascular mortality is markedly higher in Russia than in Western Europe and the US. Little is known about indicators of atherosclerotic risk in the Russian population. To our knowledge, this is the first study of apolipoprotein (apo) AI and B in Russia based on the WHO-IFCC standard. METHODS:We measure...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2003.023853
更新日期：2004-02-01 00:00:00
abstract：:Single-strand conformation polymorphism (SSCP) analysis is widely used to prescreen mutations in p53 gene. However, standardization of SSCP to detect p53 mutations has rarely been pursued so far. We have developed complete conditions for a temperature-controlled nonradioactive SSCP for mutation detection in amplified ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1997-12-01 00:00:00
abstract：:With the ultramicroanalytical system described here we can measure glucose in 1 microL of plasma or serum. The sample is placed on a dry, multilayer film element (Eastman Kodak), where a colored spot about 3.5 mm in diameter develops. The reflectance of these spots is measured with a reflectance digital matrix photome...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-12-01 00:00:00
abstract：BACKGROUND:MALDI-TOF mass spectrometry (MS) is set to make inroads into clinical chemistry because it offers advantages over other analytical platforms. These advantages include low acquisition and operating costs, ease of use, ruggedness, and high throughput. When coupled with innovative front-end strategies and appli...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2015.239491
更新日期：2016-01-01 00:00:00
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 feasibi...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：2000-12-01 00:00:00
abstract：:A modified fermentation procedure based on one described by Homer Smith in his textbook was used to eliminate glucose interference in the automated detrmination of inulin. The manifold of Fjeldbo and Stamey [J. Lab. Clin. Med. 72, 353 (1968)] was modified to enable us to insert the fermentation procedure without sacri...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-07-01 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：:A monoclonal-antibody-based competitive radioimmunoassay for measuring human protein C is reported. With use of a purified protein C standard, the solid-phase assay was sensitive to less than 80 micrograms of protein C per liter. Intraassay CVs ranged from 5% to 8%; the inter-assay CV was 5.4%. Analytical recovery ave...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-02-01 00:00:00
abstract：:A method is presented for the assay of delta-aminolaevulinate dehydratase (EC 4.2.1.24) to be performed on 10 microL of whole blood. Results compare favorably with those obtained with an accepted method (J. Clin. Chem. Clin. Bio-chem. 12: 389-390, 1974) that involves use of 200 microL of blood. ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-01-01 00:00:00
abstract：BACKGROUND:In malignancy, gene mutations frequently occur in tumor suppressor genes such as p53 and are sporadically located. We describe a homogeneous method for amplification and mutation scanning, and apply the method to the p53 gene. METHODS:Using a series of overlapping fluorescein-labeled oligonucleotides comple...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2002-08-01 00:00:00
abstract：:A rapid technique (5-10 min) has been developed for fractionating nucleotides from base and nucleoside contaminants in acid extracts of cells, by adsorption to silica gels. Silica gels (1-mL bed volume) were washed with 5 mL of water then with 5 mL of acetonitrile/water (90/10 by vol). After applying 3-mL samples, adj...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-09-01 00:00:00
abstract：:We report the measure of prostate-specific antigen (PSA) from extracts of blood dried on filter paper. Five 3-mm (diameter) paper discs containing approximately 25 microL of dried whole blood were punched from the filter paper and extracted with 500 microL of buffer. Recovery of PSA was > 92%. Imprecision of the filte...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1996-04-01 00:00:00
abstract：:Each of 65 laboratories analyzed 10 whole-blood samples for erythrocyte protoporphyrin by one or more of several analytical procedures. These procedures were of two types: (a) extraction of protoporphyrin from the erythrocytes into ethyl acetate/acetic acid, re-extraction into hydrochloric acid, and fluorometric measu...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-12-01 00:00:00
abstract：:We used enzyme immunoassay to measure apolipoprotein B concentration in human plasma. Pure lipoprotein B was isolated from serum samples of fasting normolipidemic subjects by sequential preparative ultracentrifugation and coated to a polystyrene tube surface by adsorption. Human serum samples and rabbit antiserum to h...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-03-01 00:00:00
abstract：:We evaluated a dual-precipitation method for determining cholesterol in high-density lipoprotein (HDL) and its subfractions HDL2 and HDL3. After total HDL was isolated by precipitation of very-low-density (VLDL) and low-density (LDL) lipoproteins with polyethylene glycol (Mr 8000), HDL2 was isolated from total HDL by ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-11-01 00:00:00
abstract：:We developed a new colorimetric method, DNA enzyme immunoassay (DEIA), for detecting specific hybrids of complementary nucleic acids and applied it to the detection of hepatitis B virus (HBV) DNA amplified from serum samples by means of the polymerase chain reaction (PCR) technique. The method is based on the ability ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1991-03-01 00:00:00
abstract：:Measurement of serum ascorbate may be useful in long-term population studies because of the possible influence of ascorbate on numerous physiological factors. We describe an automated method for determining ascorbate in serum and urine by using the reduction of ferric iron by ascorbate and the formation of a color bet...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-09-01 00:00:00
abstract：BACKGROUND:Iron may promote coronary atherosclerotic disease (CAD) by increasing lipid peroxidation. Studies on biochemical or genetic markers of body iron stores as risk factors for CAD have yielded conflicting results. METHODS:We studied 849 individuals with a clear-cut definition of the CAD phenotype, i.e., with (C...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2002-01-01 00:00:00
abstract：:We isolated myoglobin from sheep heart by homogenizing cardiac muscle in 70%-saturated ammonium sulfate, followed by chromatography on a column containing carboxymethyl(CM)-Sephadex gel. Two major isoforms of myoglobin, designated Mb 7.9 and Mb 8.1, were separated by chromatofocusing and were distinguished by their di...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-05-01 00:00:00
abstract：:A modified heparin-Sepharose affinity chromatography procedure (Boberg et al., J. Lipid Res. 18:544-547, 1977) was developed to determine two different triglyceride lipase activities in human post-heparin plasma: hepatic triglyceride lipase (I) and lipoprotein lipase (II). With this procedure, lipoproteins were separa...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-05-01 00:00:00
abstract：:We evaluated "borderline" increases in overnight albumin excretion rates (AERs)----i.e., those between the upper 95th percentile of normal (7.6 micrograms/min) and the lowest value currently considered predictive of nephropathy (30 micrograms/min)----to determine their importance and to see whether glucose control inf...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1991-12-01 00:00:00
