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1.
Serum concentrations of alkaline phosphatase isoenzymes and osteocalcin in normal pregnancy 总被引:4,自引:0,他引:4
A Rodin A Duncan H W Quartero G Pistofidis G Mashiter K Whitaker D Crook J C Stevenson M G Chapman I Fogelman 《The Journal of clinical endocrinology and metabolism》1989,68(6):1123-1127
We measured serum alkaline phosphatase isoenzymes and osteocalcin levels in 40 healthy women at 4-week intervals throughout uncomplicated pregnancies and 6 weeks after delivery in 17 women. Serum bone alkaline phosphatase was significantly higher in the third trimester than in early pregnancy (P less than 0.001), and this elevation was still apparent at the end of the puerperium, suggesting increased bone turnover. Serum osteocalcin was not detected (less than 0.2 micrograms/L) after the first trimester in the majority of women, and it reappeared within 48 h after delivery. The disappearance of osteocalcin after the first trimester and its rapid reappearance after delivery suggest placental clearance of this peptide. We conclude that serum osteocalcin measurements cannot be used as a marker of bone metabolism during pregnancy. 相似文献
2.
To measure myelin basic protein (MBP)-like material in cerebrospinal fluid, we compared two radioimmunoassays, both using the same antiserum to MBP but one using peptide (45-89) as the radioligand and standard (peptide assay), and the other using purified MBP as the radioligand and standard (MBP assay), with respect to their diagnostic sensitivity. Cerebrospinal fluid specimens from 185 patients with definite multiple sclerosis (MS) (n = 27), possible MS (n = 63), probable MS (n = 24), and other neurological disease (n = 71) were analyzed using both assays. The diagnostic sensitivity of the peptide assay was significantly better than that of the MBP assay in those with definite MS (sensitivity 59% and 30%, respectively); there was no significant difference in specificity. The peptide assay also showed better correlation with disease activity than the MBP assay: 14 patients classified as having active MS showed significantly higher sensitivity (78.6% versus 38%, p less than 0.04) when compared to patients with inactive disease. The MBP assay showed no significant difference between these two groups. Besides the increase in sensitivity, the actual molar concentrations of immunoreactive MBP detected using this peptide assay were considerably higher than those found using the MBP assay. These results show that the use of MBP antisera capable of recognizing epitopes present in the carboxyl half of MBP peptide (45-89) results in more sensitive detection of immunoreactive MBP when used with MBP peptide (45-89) as radiolabeled ligand in the assay. 相似文献
3.
Portwine stains were examined before, immediately after, and 1 yr after successful clearance by a pulsed dye laser (577 nm) using ultrastructural techniques. Dilated vascular channels and mast cell hypoplasia characterized lesional skin before treatment. Immediately after treatment, widespread selective vessel necrosis, similar to changes previously described, was observed. One year after laser irradiation, the abnormally ectatic portwine stain vessels had been replaced by small venules and arterioles, similar in number and diameter to blood vessels in normal skin; the only difference noted was that these new vessels were surrounded by easily identifiable mast cells. Many of these mast cells exhibited evidence of activation and degranulation. We conclude that mast cells may play an important role in the neovascularization of portwine stains treated by 577-nm dye laser irradiation. 相似文献
4.
5.
Vincent Williams Nicholas H. de Klerk Darrell Whitaker A. William Musk Keith B. Shilkin 《American journal of industrial medicine》1995,28(4):489-495
A series of 206 necropsies in Western Australia (WA) have had routine counts made of asbestos bodies in samples of lung tissue using conventional light microscopy. Thirty-two cases had worked in the asbestos industry at Wittenoom, WA and (log) counts of asbestos bodies in their lung tissue correlated well with estimates of their (log) cumulative airborne exposure to crocidolite fibers (r = 0.60). There was no association between the number of asbestos bodies and time since exposure to asbestos ceased. In subjects without known exposure to asbestos, there was a weak but nonsignificant increase in number of asbestos bodies with increasing age, with 26% of cases having no asbestos bodies present. It is concluded that the relatively simple technique of light microscopy for counting of asbestos bodies in lung tissue provides a reliable indication of the level of past occupational exposure to crocidolite in subjects whose exposure has been only to crocidolite. This could be extremely useful in follow-up studies of cohorts that lack reliable measures of airborne exposure to crocidolite asbestos. 相似文献
6.
C.C. Harland R.P. Whitaker J.L. Barron C.A. Holden 《The British journal of dermatology》1993,129(4):498-499
7.
OBJECTIVE: We aimed to determine whether general practitioner GP hospitals,
compared with alternative modes of health care, are cost- saving. METHODS:
Based on a study of admissions (n = 415) to fifteen GP hospitals in the
Finnmark county of Norway during 8 weeks in 1992, a full 1-year patient
throughput in GP hospitals was estimated. The alternative modes of care
(general hospital, nursing home or home care) were based on assessments by
the GPs handling the individual patients. The funds transferred to finance
GP hospitals were taken as the cost of GP hospitals, while the cost of
alternative care was based on municipality and hospital accounts, and
standard charges for patient transport. RESULTS: The estimated total annual
operating cost of GP hospitals was 32.2 million NOK (10 NOK = 1 Pound)
while the cost of alternative care was in total 35.9 million NOK.
Sensitivity analyses, under a range of assumptions, indicate that GP care
in hospitals incurs the lowest costs to society. CONCLUSION: GP hospitals
are likely to provide health care at lower costs than alternative modes of
care.
相似文献
8.
Interaction of Angiotensin with Disseminated Intravascular Coagulation: A Possible Mechanism in the Genesis of Acute Renal Failure 下载免费PDF全文
Alan N. Whitaker Ian Bunce Peter Nicoll Susanne V. Dowling 《The American journal of pathology》1973,72(1):1-12
Because of the importance of the renin-angiotensin system in renal homeostatic mechanisms, the effect of angiotensin administration upon disseminated intravascular coagulation has been studied in rabbits. An infusion of angiotensin II (0.1 μg/kg/min for 2 hours) produced neither histologic abnormalities in the kidneys nor an elevation of creatinine. After an infusion of thrombin (2.0 units/kg/min for 2 hours) only 3 of 10 rabbits, when sacrified 24 hours later, showed histologic lesions comprised of occasional fibrin thrombi and foci of tubular necrosis. Creatinine levels did not rise. In contrast, the combination of angiotensin and thrombin resulted in renal lesions in 12 of 14 animals. Four had frank cortical necrosis, while combinations of tubular necrosis, glomerular thrombosis and segmental glomerular infarction occurred in the others, together with elevated creatinine levels. Blockade of α-adrenoreceptors with phenoxybenzamine in 12 animals did not prevent either these histologic changes or creatinine elevation, showing that the effect of angiotensin was independent of α-adrenoreceptor stimulation. The synergistic interaction between angiotensin and disseminated intravascular coagulation was not explained by differences in the consumption of plasma fibrinogen but apparently was due to localization of fibrin thrombi within glomerular capillaries by the vasomotor actions of angiotensin, as has previously been shown to occur with α-adrenoreceptor simulation. Such a mechanism might contribute to renal glomerular deposition of fibrin in acute ischemic renal failure. 相似文献
9.
Cathepsin D (EC3.4.23.5) is an aspartyl endopeptidase involved in lysosomal proteolysis. Its functional role is uncertain. This study was undertaken to determine the cellular and subcellular distribution of cathepsin D in the normal rat ventral prostate and its possible role in the castration-induced atrophy of the gland. Cathepsin D was localized immunohistochemically to perinuclear lysosomes in secretory cells, in capillary endothelial cells, and, occasionally, in stromal cells of the untreated animal. Castration resulted in an increased number of cathepsin D-positive cells in the stroma within 24 hr. By 48 hr after castration autophagolysosomes formed in secretory cells and apoptotic bodies appeared in the epithelium. Although apoptotic bodies generally contained immunoreactive cathepsin D, a subpopulation of larger apoptotic bodies, which commonly rested on the basement membrane and contained multiple inclusions, were more variable in cathepsin D expression. The induction of cathepsin D in dendritic cells basally oriented in the epithelium was noted at 4 days of castration. These cells had a phagocytic phenotype, were distributed periodically along the basement membrane, and were not found in ductal epithelia. Treatment with actinomycin D or hydrocortisone to reduce the rate of regression of the ventral prostate blocked the appearance of these cathepsin D-positive, basally oriented epithelial cells. Our data indicate that this cathepsin D-positive, phagocytic cell differentiates from a cell resident in the prostatic epithelium. We suggest that it differentiates from basal cells in the secretory tubuloalveolar portion of the gland and that it is involved in the destruction of regressed secretory cells. 相似文献
10.
Low density adenovirus-associated virus (AAV) from upper AAV-adenovirus bands on isopycnic CsCl gradients were purified by sedimentation through sucrose gradients and by immunoprecipitation of filtered particles. These particles appeared to be “empty” capsids because of their uptake of negative stain and their lack of isotopically labeled DNA. Analysis of these particles by electrophoresis on sodium dodecyl sulfate-polyacrylamide gels demonstrated three polypeptides. These polypeptides showed identical molecular weights and the same relative concentrations as the structural polypeptides of marker complete AAV virions when compared by this technique. These findings indicate that the apparently “empty” AAV capsid does not lack any of the three polypeptides found in the complete virus particle, suggesting that none of them are core proteins. 相似文献