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991.
992.
S P Nielsen 《Journal of clinical densitometry》2001,4(3):199-207
Metacarpal index (MCI) is combined cortical thickness (both sides)) normalized with regard to outer bone diameter of the measuring site, the midshaft of the second metacarpal, or the three midmetacarpals of both hands. MCI is reduced with age, particularly in postmenopausal women. It correlates with axial bone mass in group studies. Measurement of the MCI in its modern version, digital X-ray radiogrammetry (DXR), requires only a plain analog radiograph, a PC, a film scanner, and reliable software. MCI can be used diagnostically and longitudinally for monitoring changes. MCI measured with DXR has few problems regarding accuracy and precision errors, and MCI is presently regaining lost territories among tests for quantification of bone mass and bone strength. It can be measured inexpensively and swiftly. MCI and other geometrical variables of bone can be measured on old radiographs, thus enabling estimation of cortical bone loss from the time of earlier recordings. 相似文献
993.
Mette KS Larsen Trine R Thomsen Claus Moser Niels Høiby Per H Nielsen 《BMC clinical pathology》2008,8(1):10
Background
Catheters are the most common cause of nosocomial infections and are associated with increased risk of mortality, length of hospital stay and cost. Prevention of infections and fast and correct diagnosis is highly important. 相似文献994.
995.
996.
997.
Gunnar D. Nielsen Jitka S. Hansen Rikke M. Lund Mette Bergqvist Sren T. Larsen Susanne K. Clausen Peter Thygesen Otto M. Poulsen 《Basic & clinical pharmacology & toxicology》2002,90(5):231-242
Abstract: Exposures to airborne protein antigens, aeroallergens, may cause sensitization with production of Th2‐dependent antibodies, including IgE. The IgE antibodies and associated cellular responses are responsible for the allergic airway diseases, allergic rhinitis and allergic asthma, which are increasing in societies with Western life style. Aeroallergens may have different potential to sensitize exposed subjects. Thus, there are only a limited number of important groups of aeroallergens, which are those from house dust mites, cockroaches, pets, pollens, and moulds. Allergy follows to a certain extent the pharmacological/toxicological paradigm of dose‐response relationship. Unlike effects of pharmacologically and toxicologically active substances, allergens elicit their adverse effects in a two‐stage process. In the first stage the immunologically naïve individual is sensitized to the allergen. In the second stage renewed exposure to the allergen elicits the disease response. Also, high concentrations of aeroallergens may induce immunological tolerance. The scientific literature suggests that many environmental factors contribute to the increase in sensitization and development of airway allergies. Nevertheless, the dose‐response relationships apply (within certain limits) both to the sensitization itself and to the exacerbation of the diseases. This suggest that exposure reduction may be one of the methods for reduction of risk, in relation to control of the allergic airway diseases. 相似文献
998.
Calcitonin gene-related peptide (CGRP) invariably induced a slow acting but potent relaxation of bovine retinal small arteries contracted with PGF2 alpha. Maximal relaxation obtained was 93% and 96% with a pD2-value of 8.97 and 8.86 for rat and human CGRP, respectively; thus the bovine retinal arteries cannot discriminate between CGRP from these two species. The CGRP-induced relaxation was reversible. Substance P was without effect on retinal arteries contracted with PGF2 alpha. Bradykinin relaxed 4 of 18 vessels tested in the concentration range of 11(-11)-10(-8) M whereas the vessels were contracted again at 3 x 10(-8) M. Bradykinin was without effect in the remaining 14 vessels. None of the peptides had a contractile effect on retinal arteries kept relaxed in normal buffer solution. Capsaicin 3 x 10(-5) M induced a relaxation comparable to that obtained by 10(-9) M of CGRP. The capsaicin-induced relaxation was reproducible and it was concentration dependently inhibited by ruthenium red which suggests that capsaicin releases CGRP in the arterial wall. The results indicate that CGRP has a powerful relaxing effect on the retinal vasculature indicating a role for CGRP in ocular blood flow regulation. 相似文献
999.
P T Andersen L K Nielsen J M?ller-Petersen E W Henneberg K Egeblad 《Acta chirurgica Scandinavica》1987,153(11-12):641-646
Serum phosphate levels and urinary phosphate excretion were investigated in ten patients undergoing elective abdominal aortic bypass grafting. The abdominal aorta was cross-clamped peroperatively for 50-95 min. The median serum phosphate was within reference range (0.80-1.55 mmol/l) during cross-clamping and for the first 24 hours after revascularization of the lower limbs. At 48 hours there was statistically significant fall in the serum phosphate level in all patients, with median reaching a nadir of 0.49 mmol/l. At 72 hours this level had risen to 0.69 mmol/l, and reference range had been regained 7 days postoperatively. The median urinary phosphate excretion (mmol) was 38.4 during the first 24 postoperative hours, and 34.7 and 10.0 on the 2 subsequent days. The median ratio of urinary phosphate to creatinine clearance was, respectively, 0.47, 0.37, 0.09 and 0.08 on postoperative days 1, 2, 3 and 7. The study indicated that patients undergoing aortic bypass grafting with protracted regional muscular ischemia may constitute a risk group with respect to development of severe postoperative hypophosphatemia. 相似文献
1000.
Human intoxications with inorganic mercury occur via the oral or pulmonar routes. However, earlier experimental studies of the acute toxicity of inorganic mercury primarily used parenteral administration of soluble inorganic mercury salts. The present study evaluated the effect of dose size on intestinal absorption and relative organ distribution of orally administered mercuric chloride. Experiments were performed with male mice of 2 strains (inbred CBA/Bom and outbred Bom: NMRI). At the highest dose of HgCl2, a delay in fecal elimination of non-absorbed mercury was observed indicating a decreased peristaltic rate. The fractional whole-body retention of mercury at 14 days after dosage was inversely related to the dose size, conceivably due either to saturation of the uptake mechanism or to damage to the kidneys resulting in loss of mercury with the urine at the highest dose levels. The relative organ distribution of mercury after oral exposure was quantitatively different from that reported in the literature after parenteral administration of inorganic mercury. Thus, the relative hepatic deposition was larger than after injection of mercury, presumably due to the first pass effect. A dose dependency in the relative organ distribution of retained mercury was observed, characterized by increasing relative deposition in liver, stomach, intestines, testes, spleen and carcass but decreasing relative renal deposition with increasing dose. The toxicokinetics of inorganic mercury was similar in the 2 mice strains. The present study demonstrates that the toxicokinetics of orally administered inorganic mercury is different from that of parenterally administered inorganic mercury as earlier reported in the literature. 相似文献