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1.
We report spectrophotometric methods for quantifying sodium and potassium in serum and plasma without sample pretreatment or solvent-extraction steps. The methods are based on novel chromogenic ionophores characterized by molecular structures highly preorganized for binding, which result in exceptionally high sensitivity and selectivity (negligible responses to sodium at 80 to 200 mmol/L in the potassium assay and to potassium at 0 to 10 mmol/L in the sodium assay). The within-run imprecisions are comparable with those for ion-selective electrodes (for K, 1.0% at 4.5 mmol/L; for Na, 1.1% at 136 mmol/L); the analytical range is 2-10 mmol/L for potassium, 80-170 mmol/L for sodium. The results for greater than 100 patients' samples correlated well with results obtained with ion-selective electrodes (r = 0.99 for K, 0.97 for Na). The ready-to-use aqueous reagents will be available under the trade name of ChromoLyte for use with Technicon's RA family of clinical analyzers.  相似文献   
2.
Zusammenfassung 30 Patienten mit klinisch diagnostizierter Alzheimer-Demenz (AD) und 55 etwa gleichaltrige Kontrollprobanden wurden über einen 2-Jahres-Zeitraum prospektiv klinisch, neuroradiologisch und elektroenzephalographisch untersucht, um die longitudinalen Ver?nderungen auf diesen Untersuchungsebenen und ihre Zusammenh?nge zu studieren. In der Kontrollgruppe waren im Beobachtungszeitraum keine wesentlichen Ver?nderungen auf einer der Untersuchungsebenen zu verzeichnen. Bereits inital bestanden signifikante Unterschiede zwischen Patienten und Kontrollen hinsichtlich der kognitiven Leistung, der Ventrikelweite und der absoluten Theta- und Delta-Power. Innerhalb der Patientengruppe verschlechterten sich w?hrend des zweij?hrigen Beobachtungszeitraums die Werte der Blessed-Demenzskala um 7 ± 7 Punkte und im Mini-Mental-State Test um 8 ± 4 Punkte. Die Volumina der Seitenventrikel weiteten sich um mehr als 30 % des Ausgangswertes und die absolute Delta- oder Theta-Power stieg um mehr als 10 % des Ausgangswertes an. Hierdurch nahmen die Unterschiede zwischen Kontroll- und Patientengruppe nochmals zu. Wir konnten keine Zusammenh?nge zwischen Krankheitsbeginn, Alter, Apolipoprotein E4 Gendosis und Krankheitsverlauf belegen. Ein initial schlechter Wert der Patienten auf der Blessed-Skala war mit st?rkeren morphologischen und EEG-Ver?nderungen im Verlauf korreliert, w?hrend initial hohe Theta-Power eine st?rkere funktionelle und kognitive Verschlechterung innerhalb der Patientengruppe pr?dizierte.   相似文献   
3.
Summary Comparative measuring of epidural pressure using the Spiegelberg probe 1 and ventricular fluid pressure was carried out in 15 neurosurgical intensive-care patients. Deviations in both directions were established, with a trend toward overestimating ventricular pressure in epidural pressure measuring (r=0.77). Individual pulsations, spontaneous wave courses and therapy-induced pressure changes were reflected without delays. There were no complications observed with probe implantation periods for up to 6 days. The system has been shown to be mechanically stable and easy to implant. We believe the device to be fit for trend monitoring of intracranial pressure. As with other epidural pressure monitoring systems, false assessments of ventricular pressure may lead to wrong decisions as to the required therapy.  相似文献   
4.
Levels of "free" anti-IgE autoantibodies and IgE/anti-IgE immune complexes were measured in the sera of patients with atopic dermatitis before and after treatment, psoriasis patients, and nonatopic controls. In this measurement, we used two monoclonal antibodies with distinct in vitro functions (LE 27, BSW 17), directed against the epsilon CH3 and CH4 domains of the IgE Fc-fragment, in a novel immunobinding assay. In patients with atopic dermatitis, elevated levels of "free" anti-IgE antibodies and IgE/anti-IgE immune complexes were detected in comparison to psoriasis patients and controls. In addition, there was a positive correlation between total IgE and the amount of IgE/anti-IgE complexes detected by LE 27 ( r =0.7; P < 0.001) or BSW 17 ( r = 0.64; P < 0.001) in patients with atopic dermatitis. In contrast, an inverse correlation was observed between total IgE and "free" anti-IgE antibodies ( r =−0.34; P < 0.05) in atopic dermatitis. However, serum levels of anti-IgE autoantibodies before and after therapy in patients with atopic dermatitis did not differ, and levels of anti-IgE antibodies did not correlate with clinical severity, as evaluated by an established clinical scoring system. Our data clearly indicate that significantly elevated amounts of anti-IgE antibodies could be observed in patients with atopic dermatitis, which are directed against different epitopes on the IgE molecule. It is tempting to speculate that these autoantibodies exert different effects on IgE-receptor-bearing effector cells and may play an important role in IgE regulation.  相似文献   
5.
An casuy constructed and inexpensive drop-sensing drinkometer is described, which incorporates an integrated circuit photodetector. It provides a reliable and convenient means of automatically monitoring fluid intake in a number of experimental situations. The animal is undisturbed and isolated from the electrical system components.  相似文献   
6.
Male adult spiny mice (Acomys cahirinus) were acutely challenged with a single dose of regular insulin or saline vehicle SC; either food intake, meal frequency and meal duration, or stomach emptying were then measured. Meal frequency, as well as amount eaten, was significantly higher over a 6-hr period following both 10 and 30 U/kg of insulin than following vehicle injection. Meal duration remained essentially the same across all conditions. When 30 U/kg of insulin was administered either 15 min prior to, or immediately after, a solid food meal, stomach emptying (as measured by dry weight of recovered stomach contents) was accelerated relative to vehicle controls. These data are generally consistent with and extend the comparative literature suggesting a possible link between rate of stomach emptying and insulin-induced hyperphagia in some species.  相似文献   
7.
This report describes a case of lymphocytic hypophysitis in a 63-year-old man who presented with symptoms of a pituitary mass lesion associated with hypothyroidism and hypogonadism. Postoperative endocrinological testing demonstrated gonadotropic, thyrotropic, and corticotropic hypopituitarism, and the patient was commenced on replacement therapy with hydrocortisone and levothyroxine. Histological examination of the pituitary tissue obtained by transsphenoidal surgery revealed lymphocytic hypophysitis without evidence of a pituitary adenoma. The vast majority of patients with lymphocytic hypophysitis are women particularly during pregnancy and the puerperium. Until recently only four men were reported in the literature. The pathogenesis of lymphocytic hypophysitis is uncertain but autoimmune mechanisms are possibly involved.  相似文献   
8.
The chemokines interleukin-8 (IL-8) and GRO bind in neutrophils to the interleukin-8 receptor and (IL-8R and ) triggering reorganization of the actin cytoskeleton and activation of phospholipase C (PLC). Reconstitution of chemokine-induced activation of PLC indicated coupling of IL-8R and to pertussis toxin-insensitive or . To identify the signal transduction mechanisms of chemokine-induced actin response, undifferentiated human leukemia cells (HL-60 cells) constitutively expressing , and were chosen for reconstitution studies. Expression of recombinant receptors after transfection of the cells with the cDNA of IL-8R and was confirmed by binding studies with radiolabeled ligands. IL-8R bound IL-8 with high affinity (Kd1 nM) and GRO with low affinity (Kd 1 M), whereas IL-8R bound both IL-8 and GRO with high affinity (Kd1 nM). Flow cytometric actin measurements indicated that high affinity ligand-receptor interactions in both receptor transfectants displayed inducible responses. Pretreatment of transfectants with pertussis toxin caused ADP-ribosylation of G-proteins and blocked chemokine-induced polymerization, indicating involvement of or , but not in this response.accepted by M.J. Parnham  相似文献   
9.
总结了西北各省、区医疗保险和医药卫生体制三项改革的进展情况,分析了目前存在的问题:各地改革发展不平衡,有的尚存在观望等待思想和畏难情绪;有的缺乏符合本地实际的可操作性实施方案;有的有关管理机构和人员尚未完全到位;宣传教育广度、深度不够;改革进程与中央要求及上报计划完成目标尚有一定差距。对今后工作提出几点意见:进一步解放思想,提高认识,更新观念;加强对文件的学习、宣传和培训;深入调研,制定符合本地实际情况,具有操作性配套政策和实施方案;抓点带面,搞好试点,总结经验,积极推广;加强部门协调,团结协作,同步推进“三项”改革;加强领导,加快工作进度。  相似文献   
10.
The authors describe the case of a 15-year-old boy who underwent resection of a large left temporal tumor. During a normal postoperative course, computerized tomography (CT) scanning demonstrated a spherically hyperdense structure near the internal carotid artery, enlarging on a control CT scan. A suspected false aneurysm was confirmed on magnetic resonance imaging; angiographic studies were negative. The authors believed they were dealing with a thrombosed false aneurysm and they performed operative revision. Intraoperatively the "aneurysm" could be dissected off the internal carotid artery and no lesion of the arterial wall was obvious. Histological findings showed a fresh blood clot. This case demonstrates that a blood clot may mimic an aneurysm on CT and magnetic resonance studies, which has not been described earlier. The origin of the blood clot remains unclear.  相似文献   
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