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991.
S S S?rensen T K Glud P J S?rensen A Amdisen E B Pedersen 《Nephrology, dialysis, transplantation》1990,5(4):247-257
Renal tubular sodium and water handling determined by the lithium clearance technique, plasma concentrations of atrial natriuretic peptide (ANP), angiotensin II, aldosterone, arginine vasopressin (AVP), and urinary excretion of prostaglandin E2 (PGE2) were determined both during basal conditions and before and after intravenous sodium loading with a 2.5% sodium chloride solution in patients with polycystic kidney disease (PKD), ten with normal or slightly reduced kidney function (PKDN) and seven with moderately reduced kidney function (PKDR), and in 15 healthy controls. In PKDN tubular function was normal, whereas in PKDR both proximal and distal reabsorption of sodium and water were reduced. Angiotensin II and aldosterone were normal in both groups of patients. During basal conditions ANP was higher in PKDR than in PKDN. PGE2 was significantly higher in PKDR than in PKDN. For all patients significant correlations were found between GFR and both ANP (rho = -0.51, n = 17, P less than 0.05) and PGE2 (rho = -0.53, n = 17, P less than 0.05). It is concluded that renal sodium handling is normal in the early stages of PKD. With deterioration of kidney function both proximal and distal tubular reabsorption of sodium is reduced and the accompanying changes in ANP and PGE2 may be compensatory phenomena counteracting declining glomerular filtration rate. 相似文献
992.
993.
A. E. van Leeuwen-Stok G. J. Schuurhuis A. M. Dr?ger A. W. Visser-Platier G. J. Teule P. C. Huijgens 《British journal of cancer》1996,74(4):619-624
Gallium-67 is a radionuclide that accumulates in haematological malignancies and is used for diagnostic purposes. Uptake of 67Ga into the cell occurs via the transferrin receptor, which is differentially expressed during the various cell cycle phases. With the aim of selectively increasing 67Ga uptake, we studied whether the transferrin receptor (TfR) expression could be modulated in the U937 and U715 lymphoma cell lines by cytostatic drugs inducing cell cycle phase accumulation. We tested clinically relevant drugs such as 1-beta-D-arabinofuranosylcytosine (Ara-C), hydroxyurea and methotrexate. Cytotoxicity was determined by testing the clonogenic capacity of the lymphoma cell lines. All three drugs induced an increase in S-phase content, TfR expression and 67Ga uptake in U937 and U715 single cells. The combinations of drugs and 67Ga resulted in an additive effect on the clonogenic capacity. In U937 spheroids, cultured by the fibrin clot technique, we found an accumulation in the S-phase too as well as an increase of the transferrin receptor expression after Ara-C preincubation. As in single cells 67Ga uptake was increased without synergistic effects on the clonogenic capacity. In conclusion, priming with drugs induces increased transferrin receptor expression and 67Ga uptake. Inhibition of clonogenic capacity was additive rather than synergistic. 相似文献
994.
995.
Six direct radioimmunoassays of estradiol evaluated 总被引:1,自引:0,他引:1
We evaluated the analytical performance of six commercial direct radioimmunoassays of 17 beta-estradiol, those from Radioassay Systems Laboratories, IRE Medgenix, Biotecx Laboratories, Farmos Spectria, International CIS, and Diagnostic Products Corp. The mean value for estradiol (E2) and the within- and between-run CVs were determined for serum pools and control materials, measured in seven to 10 runs with each method. Mean values for E2 in pooled sera deviated by 75% to 350% from the means measured with our routinely used extraction method. Between-run CVs ranged from 4% to 14% for the direct assays as compared with 10% for the extraction assay. We also investigated, for two of the direct assays, the effect of extraction with diethyl ether before radioimmunoassay, with respect to improvement in the agreement with our extraction method. All of the assays were easy to perform and results were obtained within 4-5 h, but we conclude that matrix effects may be expected in direct assays of estradiol. 相似文献
996.
Capsaicin cough sensitivity in allergic asthmatic patients increases during the birch pollen season. 总被引:1,自引:0,他引:1
Dan Weinfeld Ewa Ternesten-Hasséus Olle L?whagen Eva Millqvist 《Annals of allergy, asthma & immunology》2002,89(4):419-424
BACKGROUND: A change in neural responsiveness may occur as the result of allergic inflammation in the lower airways as well as in the upper airways. In the lower airways, capsaicin cough sensitivity is known to reflect sensory neural reactivity. OBJECTIVE: The aim of this study was to establish whether allergic inflammation changes airway neural sensory reactivity during prolonged allergen exposure. METHODS: Ten nonsmoking patients with birch pollen-allergic asthma performed a capsaicin inhalation challenge twice, once in the off-pollen season and once during the pollen season. The number of coughs and symptoms induced by capsaicin were recorded and compared with those of healthy control subjects. RESULTS: The response to capsaicin, expressed as number of coughs, increased in a dose-dependent manner during both tests. Before the season, the response was similar to that of healthy control subjects, but during the pollen season, the reactivity was significantly increased. Variations in forced expiratory volume in 1 second were not significant before and after each challenge, and values did not change during the pollen season as compared with the winter season. CONCLUSIONS: Sensory reactivity in allergic asthmatic patients may be increased during prolonged allergen exposure as during the pollen season. This finding suggests that allergic inflammation in the lower and/or upper airways may trigger neurogenic mechanisms of significant clinical importance. 相似文献
997.
998.
Y Wengstr?m C H?ggmark H Strander C Forsberg 《European Journal of Oncology Nursing》2000,4(2):78-88; discussion 89-90
The purpose of this study was to describe symptoms, side-effects and quality of life (QoL) of women with breast cancer during and following treatment with radiation therapy. The sample consisted of 134 women with breast cancer. Symptoms were measured using a modified version of the Oncology Treatment Toxicity Tool (OTTAT) and QoL was measured using the Cancer Rehabilitation Evaluation System-short form (CARES-sf). The results showed an increase in experienced symptoms and their severity as the treatment progressed. QoL was perceived as poorest at baseline before treatment had started. During the treatment, QoL scores leveled out and an improvement could be seen after completion of treatment. The study findings provide directions and suggestions for assessment and management of perceived symptoms for women receiving radiation therapy for breast cancer from the second week and up to 2 weeks after completion of therapy is the critical time-period for targeting interventions for experienced symptoms and side-effects from radiation therapy. 相似文献
999.
1000.