Abstract:
:We determined approximately 15,000 laboratory values in 236 individuals between the ages of 60 and 90 y, 22 individuals between 90 and 99 y, and 69 individuals greater than or equal to 100 y, and compared these with values in young adults. We tested 47 different analytes in the 60-90-y group and 93 analytes in the greater than or equal to 90-y group. Na, K, Cl, and CO2 values were either identical or showed minimal change with age; pH decreased slightly. Differences in Ca values were only minor, but ionized Ca increased slightly. Phosphate decreased in men, but changed only minimally in women; parathyroid hormone increased with age. Increases with age were also observed for glucose, insulin, and C-peptide. Among the enzymes, alkaline phosphatase increased in women, but in men only greater than 90 y; gamma-glutamyltransferase increased in both sexes. Creatine kinase (CK) decreased slightly in individuals greater than 70 y and markedly in those greater than 90 y of age, whereas CK-MB decreased markedly greater than 70 y, reaching the detection limit in individuals greater than 90 y. Lactate dehydrogenase isoenzyme 5 decreased slightly with age. Urea nitrogen increased gradually with age, but creatinine increased only in individuals greater than or equal to 90 y. The increase in urea is not paralleled by a loss of protein in urine, suggesting that the possible cause of azotemia may not always be renal pathology. Urate increased in women but not in men. Liver function, as measured by total bilirubin and liver enzymes, was exceedingly well maintained. Concentrations of most proteins show little change, except for slight decreases in prealbumin, albumin, and transferrin, proteins used as an index of nutritional status. IgA values increased, IgG ranges were wider, IgM and IgD decreased, and the range for IgE was narrower than in young adults. Cholesterol, high-density lipoprotein cholesterol, and triglyceride values increased with age, but decreased in individuals greater than or equal to 90 y. Among the trace elements, magnesium changed little, zinc and lead decreased, and copper values increased with age. Total triiodothyronine and thyroxine decreased, with concomitant increases in thyroid-stimulating hormone. More individuals had increased microsomal antibodies and thyroglobulin titers in the aging population than in the young. In men, the free, percent free, bioactive, and total testosterone values decreased, but luteinizing hormone (LH) and follicle-stimulating hormone (FSH) values increased. In women, estrone and estradiol values decreased, with concomitant increases in LH and FSH. Androstenedione and progesterone decreased in both sexes.(ABSTRACT TRUNCATED AT 400 WORDS)
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Tietz NW,Shuey DF,Wekstein DRsubject
Has Abstractpub_date
1992-06-01 00:00:00pages
1167-85issue
6eissn
0009-9147issn
1530-8561journal_volume
38pub_type
杂志文章abstract::The biological variability of total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and calculated low-density lipoprotein cholesterol (LDL-C) was determined in three serial (monthly) capillary and venous specimens from 83 subjects. The analytes were quantified with a desktop analyz...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1996-12-01 00:00:00
abstract::We studied chemical speciation of arsenic compounds in urine samples by using HPLC with inductively coupled plasma mass spectrometry detection. We examined urinary arsenic excretion patterns and the arsenic species excreted from nine human subjects who ingested seaweed products and crab (or shrimp). Fast urinary excre...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1994-04-01 00:00:00
abstract::Three different techniques of lipase (EC 3.1.1.3) determination (titrimetry, nephelometry, and enzyme immunoassay) were used to investigate an interesting effect of ionic strength on enzyme activity. Both activation in the presence of NaCl (140 mmol/L) and strong immunoinhibition were observed for lipase from plasma o...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-03-01 00:00:00
abstract::Ammonia concentrations in plasma may increase because of contamination and deterioration of blood components during specimen handling and storage. Using replicate specimens from healthy volunteers, we studied influences of specimen processing and storage procedures on ammonia measurements made with a self-contained re...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-06-01 00:00:00
abstract:BACKGROUND:Altered germline expression of genes may represent a powerful marker of genetic or epigenetic predisposition to cancer or other diseases. METHODS:We developed and validated a method of nonfluorescent primer extension that uses a single dideoxynucleotide and denaturing HPLC (DHPLC) to analyze the relative al...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2009.126300
更新日期:2009-09-01 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::We combined the amplification refractory mutation system (ARMS) and fluorescence polarization (FP) to give a homogeneous genomic DNA genotype analysis method. Oligonucleotide probes labeled with the fluorescein dyes fluorescein isothiocyanate and 5-([4,6-dichlorotriazin-2-yl]amino)fluorescein and the rhodamine dye 6-c...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1997-08-01 00:00:00
abstract::Proteinuria, long recognized as a sign of renal disease, is a common laboratory abnormality in children and adults. Proteinuria may be transient or persistent; when persistent, the cause must be determined. Proteinuria may be primarily glomerular or tubular in origin. Glomerular proteinuria is usually an important con...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1989-05-01 00:00:00
abstract::To establish optimum conditions for creatine kinase (EC 2.7.3.2) activity measurement with the creatine phosphate in equilibrium creatine reaction, we re-examined all kinetics factors relevant to an optimal and standardized enzyme assay at 30 and 25 degrees C. We determined the pH optimum in vaious buffers, considerin...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1976-05-01 00:00:00
abstract:BACKGROUND:Whether low plasma 25-hydroxyvitamin D concentrations cause osteoporotic fractures is unclear. We tested the hypothesis that low plasma 25-hydroxyvitamin D concentrations are associated with increased risk of osteoporotic fractures using a Mendelian randomization analysis. METHODS:We genotyped 116 335 rando...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1093/clinchem/hvaa049
更新日期:2020-05-01 00:00:00
abstract::Lyophilized serum specimens were manufactured in such a way that fixed quantitative interspecimen relationships were established. The specimens were analyzed for about twenty constituents by several thousand laboratories in 1971, 1972, and 1973. Most of the consensus mean values derived from these analyses were found ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1976-07-01 00:00:00
abstract:BACKGROUND:Simple, reproducible assays are needed for the quantification of sphingolipids, ceramide (Cer), and sphingoid bases. We developed an HPLC method for simultaneous quantification of total plasma concentrations of Cer, glucosylceramide (GlcCer), and ceramide trihexoside (CTH). METHODS:After addition of sphinga...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2006.079012
更新日期:2007-04-01 00:00:00
abstract:BACKGROUND:Diabetes mellitus has been historically divided into type 1 and type 2 diabetes, with type 1 being an autoimmune disease and type 2 being primarily a metabolic disease. CONTENT:The current diabetes classification scheme needs to be reevaluated because of the accumulating evidence of immune system involvemen...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:10.1373/clinchem.2010.148270
更新日期:2011-02-01 00:00:00
abstract::This improved assay of rheumatoid factors in serum, described here for use with the Baker "Encore" centrifugal analyzer, is efficient, with 250-sample throughput per hour; reproducible, with between-batch CV = 5% and within-batch CV = 2% (mid-assay range); and results correlate well (r = 0.9) with those by other metho...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-02-01 00:00:00
abstract::Four commercial products for urine glucose determination were evaluated and compared with a quantitative hexokinase procedure. We examined precision, sensitivity, and analytical recovery of glucose from glucose-supplemented urine samples and comparison of methods, using patients' samples. Only "Chemstrip uG" (Bio-Dyna...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-10-01 00:00:00
abstract::To evaluate a theoretical model for calculating free thyroid hormones, based on the law of mass action, we compared values for both calculated and measured free thyroxin and free triiodothyronine in a group of normal subjects. To determine whether the concentrations of circulating free hormones were also predictable f...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-06-01 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::We describe a method for measuring urinary oxalate and citrate with capillary electrophoresis (CE) and indirect ultraviolet absorbance detection. Sample preparation is minimal, requiring an acidification, brief centrifugation, and dilution. The method is rapid, with oxalate and citrate having mean migration times of 4...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1995-09-01 00:00:00
abstract::We modified the ISO-DALT two-dimensional gel electrophoresis system to allow the routine examination of serum specimens from patients with monoclonal gammopathies. This system, MC-Iso 1, is characterized by a broad pH gradient for resolving the basic immunoglobulin heavy and light chains. The increased resolution of b...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-04-01 00:00:00
abstract::To correct the results of a radioimmunoassay for beta-thyrotropin (TSH) subunit by eliminating the proportion ascribable to intact TSH, we have devised a method that experimentally reproduces the conditions under which the interference develops. Beta-TSH subunit was assayed in several preparations containing known con...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-05-01 00:00:00
abstract:BACKGROUND:Coffee consumption has been associated with several risk factors for coronary heart disease, including increased cholesterol, increased blood pressure, and increased plasma total homocysteine (tHcy). tHcy is determined by several B-vitamins. However, reports about the association between coffee intake and B-...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2008.103465
更新日期:2008-09-01 00:00:00
abstract:BACKGROUND:Dried blood spots (DBS) are a convenient and inexpensive method for biobanking. Although many countries have established population-based DBS biobanks from neonatal screening programs, the quality and usefulness of DNA from DBS have not been extensively assessed. METHODS:We compared 4 common DNA extraction ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2007.087510
更新日期:2007-08-01 00:00:00
abstract:BACKGROUND:Advances in the biological sciences and technology are providing molecular targets for diagnosing and treating cancer. Current classifications in surgical pathology for staging malignancies are based primarily on anatomic features (e.g., tumor-node-metastasis) and histopathology (e.g., grade). Microarrays to...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:2002-08-01 00:00:00
abstract::The IFCC-recommended procedure for aspartate aminotransferase (EC 2.6.1.1) was adapted to the centrifugal analyzer and evaluated during five years. The main hindrance to widespread use of the recommended method is the need for pre-incubation with pyridoxal phosphate. The present method includes a 10-min pre-incubation...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-01-01 00:00:00
abstract::The currently available radioimmunoassays of trypsin measure total immunoreactive trypsin (EC 3.1.1.7), which includes both trypsinogen and alpha 1-protease inhibitor-bound trypsin. Hitherto, the only way to differentiate these two forms of trypsin has been to fractionate them on a gel-filtration column. We describe h...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-09-01 00:00:00
abstract::We developed a simple method for the analysis of bismuth (Bi) in biological tissue, using wet digestion for sample pretreatment. Bi was determined by electrothermal atomic absorption spectrometry with platinum as a matrix modifier to decrease the volatility of Bi. The furnace program included a gas stop for sensitivit...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1993-05-01 00:00:00
abstract::Using image-analyzing equipment, we measured the effect of quinidine on the activity of naphthol AS-D chloroacetate esterase, alpha-naphthyl butyrate esterase, alpha-naphthyl acetate esterase, and acid phosphatase in individual cells of a human Hep G2 hepatoma cell line. The impact of the drug on the morphology of the...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-03-01 00:00:00
abstract::In this method for separating glycosylated from nonglycosylated hemoglobin in blood by electrophoresis on cellulose acetate membranes, we exploit the affinity of low-molecular-mass dextran sulfate for the nonglycosylated fraction, which increases the mobility of the latter relative to that of glycosylated hemoglobin. ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1983-02-01 00:00:00
abstract:BACKGROUND:Hypoxic ischemic encephalopathy (HIE) is a major cause of permanent neurological disabilities in full-term newborns. We measured activin A in urine collected immediately after birth in asphyxiated full-term newborns, and assessed the ability of the measurements to predict the occurrence of perinatal encephal...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2005.062604
更新日期:2007-03-01 00:00:00
abstract:BACKGROUND:Measurement of postimmunization antibody response to pneumococcal capsular polysaccharide (caps-PS) is the standard method to identify deficiency of antipolysaccharide antibody production. However, no standardized criteria have been defined for classification of patients into responders or nonresponders to c...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2006.080051
更新日期:2007-03-01 00:00:00