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M Christensen

Publications and source records attributed to M Christensen.

At least 127 records · Page 7Linked to original sources
PubMed1986

Liver-cell adenoma. Case report.

A young woman taking oral contraceptives presented with acute, severe abdominal pain. A liver-cell adenoma (weight 1.6 kg), with intrahepatic bleeding and necrosis, was enucleated at elective laparotomy. The clinical presentation of liver-cell adenoma, ranging from incidental finding to sudden death, is reviewed and the evidence linking oral contraceptives to the tumour is discussed. Reported cases of symptomatic liver-cell adenoma have numerically declined in the past decade. Acute surgical treatment is indicated only to control bleeding. In addition to withdrawal of oral contraceptive medication, enucleation of the tumour or hepatic resection is generally recommended as elective, definitive treatment.

Adult↗
PubMed1986

Reliability for an imaging test: evaluation of scintigraphy to reveal liver state in gastrointestinal cancer.

In 185 consecutive, surgical patients with suspected or proven gastrointestinal cancer a preoperative liver scintigraphy was performed; liver metastases were bioptically verified in 28 patients. A seven-class descriptive system was used for blind classification of the scintigraphies according to conferential consensus. Two years later (with the knowledge of the verified incidence of metastatic liver disease) the scintigraphies were reclassified. Considering the verified state of the patients, the latter classification was substantially improved. Probability for metastatic disease increased with more abnormal class label. At best, reliability for a twice interpreted scintigraphy as a binary test to denote the true state of the liver was 92 percent. The best cut-off level for diagnostic purposes yields a probability of 1.00 for an abnormal scintigraphy to denote liver metastases, accepting that 54 percent of patients with liver metastases were not found. For screening purposes, at best, a probability of 0.98 for a normal scintigraphy to denote no liver metastases was noted; thus, 83 percent of patients with normal liver state were missed. In conclusion, we find the liver scintigraphy classification system useful to find or exclude metastases in the test population and we think the procedure applied could be useful as a vehicle to report test results for any imaging modality.

Gastrointestinal Neoplasms↗
PubMed1986

Reproducibility of an imaging test: evaluation of dual liver scintigraphy by a long-term procedure.

A seven-class classification system for liver scintigraphy was developed to find or exclude metastases in a clinically defined population with gastrointestinal tumours. Scintigraphy was performed twice in fifty patients a few days apart. During a period of three years each scintigraphy was classified thrice as a consensus between two experienced observers at six occasions placed on three separate days. No substantial change in classification was seen whether the same scintigraphy was interpreted twice in a day or three years apart, although considerable uncertainty was seen in interpretation of near-normal scintigraphies. In dual scintigraphies, a significant lower reproducibility was noted--directly visualized in 10 percent of the patients--indicating that a recorded difference does not necessarily reflect a change in patient situation. We think the applied procedure may be valuable for evaluation of any imaging system for clinical use.

Gastrointestinal Neoplasms↗
PubMed1986

The value of clinical assessment for preoperative prediction of liver metastases in suspected gastrointestinal cancer. A prospective, consecutive study.

Surgeons' ability to predict liver metastases preoperatively was studied in 185 operable, nonicteric patients strongly suspected to have gastrointestinal cancer. The prediction was based on a clinical assessment comprising medical history, physical examination and low-cost laboratory tests. A pathoanatomic verification procedure was used. The observed predictive value of a positive test was 0.67 and there was a false-negative ratio of 0.79. At the clinical assessment, presence of metastases was believed to be more common in gastric than in colorectal disease (6/43 vs. 3/142), but the actual incidence of metastases was similar in the two groups. Serum alkaline phosphatase (AP) was a priori believed to be of value in the clinical assessment. But the clinical assessment with inclusion of AP was inferior to AP alone as a predictor of metastases, due to undervaluation of the importance of elevated AP in cases of colorectal disease. The difficulties in standardization of the clinical assessment are underlined.

Adult↗
PubMed1985

The amino acid sequence of pancreatic spasmolytic polypeptide.

The sequence of porcine pancreatic spasmolytic polypeptide has been established by a variety of techniques including manual as well as automatic sequencing of fragments resulting from the cleavage of reduced and S-carboxymethylated pancreatic spasmolytic polypeptide with trypsin, chymotrypsin, clostripain, cyanogen bromide and formic acid. The N- and C-terminal sequences were established using pyroglutamate amino-peptidase and carboxypeptidase A, respectively. Pancreatic spasmolytic polypeptide contains 106 amino acid residues in a single chain with seven S-S bridges and a pyroglutamyl blocked N-terminal. The alignment of the sequences representing amino acids 14-49 and 63-98 shows pair-wise identical amino acid residues in 18 out of 36 positions, indicating that these two "domains" have been derived from a common gene.

Amino Acid Sequence↗
PubMed1985

Estimation of 131I-hippuran blood activity from externally registered activity.

The application of data-processing methods such as deconvolution or computer-assisted background subtraction to renography requires knowledge of the input to the kidneys. The two most commonly used approximations to the kidney input in 131I-hippuran probe renography are to assume that the kidney input is described either by the time-activity curve recorded over the subclavian region (mode I) or by the time derivative of mode I (mode II). A third approximation to the kidney input using two externally recorded time-activity curves, pre-injection of 131I-albumin and two venous samples has previously been described. This approach has been modified in this work, in which two externally recorded time-activity curves and two capillary samples are used to construct an estimate for the kidney input (mode III). The three modes are compared with a reference, which is constructed from capillary samples drawn during the renography examination. Eleven patients participated in this study, all of whom were referred for routine renography. The results show that only mode III is close to the reference in all cases.

Adult↗
PubMed1985

Hodgkin's disease in sarcoidosis. A case report and a review of the literature.

A patient with Hodgkin's disease preceded by sarcoidosis is presented and the difficulties introduced by the lack of specificity for the sarcoid-like granulomas to differentiate between the dual pathology are discussed. A review of the literature disclosed 9 similar case reports. It is suggested that the finding of non-caseating epithelioid cell granulomas in relatively old patients with lymphadenopathy, systemic symptoms and absolute neutrophil leucocytosis could be warning signals of the appearance of Hodgkin's disease.

Hodgkin Disease↗
PubMed1985

Serum concentrations of vitamin D metabolites in different degrees of impaired renal function. Estimation of renal and extrarenal secretion rate of 24,25-dihydroxyvitamin D.

The serum levels of 25-hydroxycholecalciferol, 24,25-dihydroxycholecalciferol, and 1,25-dihydroxycholecalciferol were measured simultaneously in three groups of adults with different renal function: normal (n = 24), glomerular filtration rate (GFR) greater than 70 ml/min; moderately decreased (n = 15), GFR 5-35 ml/min, and severely decreased (n = 27), GFR less than 5 ml/min. 25-hydroxycholecalciferol was normal in both patient groups with decreased renal function. 1,25-dihydroxycholecalciferol was halved in the group with moderately decreased renal function (p less than 0.01) and severely decreased (almost undetectable) in the group with severely decreased renal function (p less than 0.01). In contrast, 24,25-dihydroxycholecalciferol was normal in the group with moderately decreased renal function and only halved (p less than 0.05) in the group with severely decreased renal function. These findings suggest extrarenal C-24 hydroxylase activity which may be stimulated by decreasing renal function, thus decreasing renal C-24 hydroxylase activity.

24,25-Dihydroxyvitamin D 3↗
PubMed1985

Bone mineral loss during centre and home haemodialysis. Influence of vitamin D metabolites and serum parathyroid hormone.

Twenty-seven patients on chronic haemodialysis were investigated for a mean of 4.8 years (3.0-6.5 years). Mean bone mineral content fell constantly and similarly at a rate of three to four per cent per year in both centre (n = 14) and home (n = 13) haemodialysis patients. Mean serum values of 25(OH)D3 (normal), 24,25(OH)2D3 (decreased to half the normal level and 1,25(OH)2D3 (severely decreased and almost non-detectable) were similar in patients with a rapid bone mineral content loss (greater than 10%/3 years) and a slow bone mineral loss (less than 10%/3 years). Mean serum parathyroid hormone was markedly elevated, but significantly higher (about twice the level) in the 'rapid losers' than in the 'slow losers'; whereas the two groups did not differ with regard to mean serum concentrations of calcium, phosphate and alkaline phosphatase.

Adult↗
PubMed1984

Human proinsulin standards.

Two new batches of pancreatic human proinsulin have been compared with biosynthetic human proinsulin. Standards of these three proinsulin preparations were made on the basis of quantitative amino-acid analyses and compared in two proinsulin radioimmunoassays with a proinsulin standard prepared 14 years ago. The curves of the new standards were superimposable. However, they differed considerably from the curve of the old standard which proved to be only one-third of the strength of the new standards, thereby leading to a threefold over-estimation of proinsulin concentrations when the old standard is used. We conclude that the new standards should replace previously used standards.

Amino Acids↗
PubMed1983

[Limy bile].

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Abdomen, Acute↗
PubMed1983

Bone mineral content in patients on prolonged maintenance hemodialysis: a three year follow-up study.

Bone mineral content (BMC) was measured annually over a three year period in 31 consecutive patients on maintenance hemodialysis (HD). No patient had received treatment with vitamin D derivatives, anticonvulsants or corticosteroids, nephrectomy or a renal transplant. Initial median BMC value in per cent of sex and age matched normal mean was significantly decreased to 91.0% (P less than 0.01), indicating bone mineral loss in chronic renal failure prior to HD. During HD a highly significant fall in mean BMC (in per cent of initial value) continued to 95.1%, 92,7% and 90.8% after 1, 2 and 3 years, respectively, with no influence of age, sex or initial BMC value. The interindividual variation in BMC changes, however, was considerable: the BMC loss over 3 years exceeded 10% in 13 (42%) patients ("rapid losers") while 12 (39%) patients had a BMC loss below 5%, or no loss at all. The "rapid loser" group had significantly higher serum levels of parathyroid hormone and alkaline phosphatases and, moreover, developed a lower serum phosphate and calciumXphosphorus product than the other group of patients ("slow losers"). The mean BMC loss over 3 years of HD was pronounced and significant (P less than 0.02) in patients with chronic pyelonephritis (9.8%) and polycystic kidney disease (14.2%), but much smaller, and not significant, in patients with chronic glomerulonephritis (4.8%). It is concluded that a selection of patients with a high degree of bone mineral loss during HD is not possible by means of sex, age, initial BMC, biochemical parameters, or diagnosis (2 patients with chronic glomerulonephritis appeared to be "rapid losers"). For that purpose a high-precision BMC method is mandatory.

Adult↗
PubMed1982

Bioavailability of zinc from a diet based on isolated soy protein: application in young men of the stable isotope tracer, 70Zn.

With the aid of the stable isotope, 70Zn, as a tracer and neutron activation analysis, a combination of extrinsic labeling of meals and fecal monitoring of isotope excretion was used as a safe and noninvasive approach for assessing the effects of the vegetable (soy) and animal (milk, beef) proteins on the absorption of zinc in healthy, adult human volunteers. A known amount of 70Zn was added as ZnCl2, to six consecutive meals over a 2-day period during which either one of three isonitrogenous liquid formulas (skim milk; soy isolate; or a 50:50 mixture) or one of two bologna sausages (soy isolate of beef) were given. The mean absorption of 70Zn from milk, soy and soy/milk was 41 +/- 4, 34 +/- 4, and 41 +/- 7% (mean +/- SEM), respectively, the presence of soy protein having no effect on absorption of the extrinsic label. For beef bologna and soy bologna, fractional absorption of the 70Zn tracer was 41 +/- 4 and 30 +/- 3%, respectively. Beef might favor absorption of extrinsic zinc. The kinetics of isotope excretion, pooling procedures, for stool samples and the utility of fecal markers were also evaluated.

Adult↗