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71.
72.
CF Lanata RE Black H Creed-Kanashiro F Lazo ML Gallardo H Verastegui KH Brown 《Acta paediatrica (Oslo, Norway : 1992)》1992,81(S383):98-103
Dietary intake during diarrhea in children less than three years of age was estimated from information recorded on illustrated dietary forms used by children's caretakers during the first week of illness in a prospective community-based study of diarrheal diseases in Lima, Peru. The frequency of consumption and the amount consumed of food groups and selected commonly consumed foods were analyzed by the final duration of the diarrheal episode. Cereals were less frequently consumed during the acute phase of diarrheal episodes that ultimately became persistent (>14 days'duration), apparently shortening the duration of the episode by one day (median duration of four days in children not consuming vs three days in children consuming cereals during diarrhea, p <0.02 Kaplan-Meier logrank test). Only roots and tubers (mainly potatoes) were consumed in greater quantity during episodes that became persistent. There was no evidence that consumption of breast milk or non-maternal milk was associated with an alteration in diarrheal duration. This study provides further evidence of the beneficial effects of continuing feeding during diarrhea using foods available at the home level, especially cereals, which are commonly used in the diet of young children. 相似文献
73.
KH Mak ES Ang ASW Goh KX Na FX Sundram ATH Tan 《Journal of Medical Imaging and Radiation Oncology》1995,39(2):112-117
Technetium-99m hexakis-2-methoxy-isobutyl-isonitrile(99mTc sestamibi) has been used for myocardial perfusion imaging in the evaluation of coronary artery disease (CAD) since 1990. The experience of its use in an Asian population with and without previous myocardial infarction (Ml), diabetes mellitus (DM), hypertension (HPT) and collateral circulation (COL) is reported. One hundred and thirty-nine patients who underwent treadmill exercise testing with 99mTc sestamibi single photon emission computed tomography (SPECT) and coronary angiogram were studied. The overall sensitivity for the detection of CAD was 91.0% and specificity was 64.7%. For patients without previous myocardial infarction, the sensitivity was 83.8% and specificity was 83.3%. Patients with COL had a higher sensitivity while those with HPT had a lower specificity. Sensitivity was higher in patients with multi-vessel disease (MVD) than single vessel disease (SVD). The overall detection for individual artery stenosis was 74.1% with a specificity of 73.1 %. Amongst the three major coronary arteries, sensitivity was highest for the right coronary artery and specificity was highest for the left circumflex artery. Specificity was higher in patients without MI or COL. We found that the agreement between 99mTc sestamibi SPECT and coronary angiogram for the extent of CAD was only 52.5%. The concordance rate was higher for patients with MVD than SVD. It is concluded that 99mTc sestamibi SPECT is a sensitive and specific test for the detection of CAD and localization of disease to individual coronary arteries in our patients with some differences in the subgroups. Agreement between coronary angiogram and 99mTc sestamibi for the extent of coronary artery disease was also satisfactory. 相似文献
74.
Modulation of sympathetic activity by corticotropin-releasing hormone and atrial natriuretic peptide 总被引:2,自引:0,他引:2
BACKGROUND: Heart rate variability represents a reliable marker to delineate the status of autonomic nervous system (ANS) function and alterations due to stress in vivo. Interestingly, up to now the effects of corticotropin-releasing hormone (CRH), a key regulator of the stress hormone system, upon heart rate variability are not sufficiently described. Hence, we attempted to investigate the ANS-effects of a CRH bolus and the modulatory influences of atrial natriuretic peptide (ANP), one of the most important functional antagonist of CRH actions.METHODS: 12 healthy male volunteers were administered 100 microg CRH as bolus injection at 15:00. Six randomly chosen subjects received 150 microg ANP dissolved in normal saline and six subjects a normal saline infusion from 14:45 to 15:15. From 13:00 to 17:00 an ECG was recorded and mean heart rate (HR), total power (TP), very low frequency (VLF), low frequency (LF), LF in normalized units (LF [nu]), high frequency (HF) domains and the LF/HF-ratio in the interval from 14:00 to 16:00 were determined.RESULTS: After administration of CRH a significant increase in HR and a fast reduction of TP were observed, which lasted about 1 h. Based upon spectral domain analyses the sympathetic activity after CRH administration as indicated by LF [nu] increased by 31% (mean location) during saline. Applying ANP this increase was reduced to 19% (mean location). The VLF component, which is considered to be based in part also on sympathetic influences, indicates comparable effect. During saline the VLF after CRH bolus remained largely unchanged, but was reduced to 66% by ANP. Though the vagal activity indicated by the HF component was reduced after CRH, no significant differences emerged between both treatments. The changes of the LF/HF-ratio were pronounced in both groups. During saline this ratio increased by about 111%, during ANP only by 43% (mean location).CONCLUSIONS: Based upon HRV analysis the CRH administration induced sympathotonic effects which were antagonized by ANP. The observed vagal changes were less pronounced and need further investigation. Further studies of autonomic effects by alterations of CRH secretion in depression and anxiety disorder are strongly warranted. 相似文献
75.
Müller C Bittmann I Hatz R Kellner B Schelling G Fürst H Reichart B Schildberg FW 《European surgical research. Europ?ische chirurgische Forschung. Recherches chirurgicales européennes》2002,34(1-2):77-82
BACKGROUND: Reperfusion injury represents a severe early complication following lung transplantation. Among the pathogenetic factors, the high potassium content of Euro-Collins(reg) solution is discussed. MATERIAL AND METHODS: In a pig model of orthotopic left-sided lung transplantation we investigated the effect of Euro-Collins solution (EC: n = 6) versus low potassium dextran (LPD: Perfadex: n = 6). Sham-operated (n = 6) animals served as control. Transplant function, cellular energy metabolism and endothelial morphology served as parameters. In a clinical investigation, 124 patients were evaluated following single (EC: n = 31; LPD n = 37) or double (EC: n = 17; LPD n = 39) lung transplantation, whose organs where preserved with EC (n = 48) or LPD (n = 76). Duration of ischemia, duration of ventilation and stay on ICU were registered. Primary transplant function was evaluated according to AaDO(2) values. Cause of early death (30 days) was declared. RESULTS: Experimental results: After flush with EC and 18 h ischemia, a reduction of tissue ATP content (p < 0.01 vs inital value and LPD) was noted. Endothelial damage after ischemia was severe (p < 0.05 vs control), paO(2) was significantly decreased. Clinical results: In the LPD group, duration of ischemia was longer for the grafts transplanted first (SLTx and DLTx: p = 0.0009) as well as second (2. organ DLTx: p = 0.045). Primary transplant function was improved (day 0: SLTx: p = 0.0015; DLTx: p = 0.0095, both vs EC). Duration of ventilation and stay on ICU were shorter (n.s.). Reperfusion injury-associated death was reduced from 8% (EC) to 0 (LPD). CONCLUSION: In experimental lung preservation, LPD lead to an improved graft function. These results were confirmed in clinical lung transplantation. Clinical lung preservation, therefore, should be carried out by use of LPD. 相似文献
76.
Patient safety technology for microadsorbent systems in extracorporeal blood purification 总被引:2,自引:0,他引:2
Falkenhagen D Strobl W Hartmann J Schrefl A Linsberger I Kellner KH Aussenegg F Leitner A 《Artificial organs》2002,26(2):84-90
Alternative technologies for extracorporeal blood purification systems based on microadsorbents in suspension are discussed. Principally, microadsorbents offer higher efficiency and flexibility when compared to conventional column-based adsorption systems. Systems already clinically employed (e.g., BioLogic DT) or close to clinical application (e.g., the microspheres-based detoxification system, MDS) are described. The MDS technology, in particular, is characterized by efficiency and a high degree of flexibility with respect to both the use of different adsorbents as well as the combination with hemodialysis/hemofiltration therapy. It was designed for continuous use in intensive-care units, but enables also the removal of low-density lipoprotein, fibrinogen, autoimmune antibodies, immune complexes, and other pathophysiologically relevant substances. Alternative anticoagulation regimes and safety systems on fluorescence sensor technology have recently been developed for the MDS and are presented in this paper. 相似文献
77.
We report on the recurrence of Candida albicans among yeast isolates from our university hospital. After a decline in occurrence which coincided with the onset of the use of fluconazole, the fraction of C. albicans recovered and at present has reached the pre-fluconazole level. No permanent rise of C. glabrata or C. krusei has been observed. 相似文献
78.
M Kellner A Yassouridis Y Hua M Wendrich H Jahn K Wiedemann 《Journal of psychiatric research》2002,36(1):1-6
Given the anxiogenic effects of the type-B natriuretic peptide receptor agonist C-type natriuretic peptide (CNP) in rodents, we investigated the influence of CNP pretreatment upon the behavioral and endocrine action of the panicogen cholecystokinin tetrapeptide (CCK-4) in healthy men. In a randomized double-blind balanced design, 20 male volunteers were given an intravenous infusion of 300 microg of CNP vs. placebo followed by 25 microg of CCK-4. The behavior was assessed using panic, anxiety, and dissociation questionaires before the infusion and after the CCK-4 stimulus. Furthermore, the stress-sensitive hormones adrenocorticotropic hormone (ACTH), cortisol, and prolactin were measured. CNP pretreatment enhanced the anxiogenic and prodissociative effects of CCK-4 and significantly augmented the ACTH surge after CCK-4. However, no effect of CNP was seen upon panic symptoms. Our preliminary data support a role of type-B natriuretic peptide receptors in anxiety modulation in normal man. 相似文献
79.
Kellner M Baker DG Yassouridis A Bettinger S Otte C Naber D Wiedemann K 《The American journal of psychiatry》2002,159(11):1938-1940
OBJECTIVE: The study examined whether enhanced limbic mineralocorticoid receptor activity resulting in negative glucocorticoid feedback could contribute to the diminished basal and stress-induced cortisol output reported in patients with posttraumatic stress disorder (PTSD). METHOD: The effects of acute antimineralocorticoid (spironolactone) versus placebo pretreatment on levels of plasma cortisol at baseline and after stimulations with corticotropin-releasing hormone (CRH) and on adrenocorticotropic hormone (ACTH) level were measured in 12 PTSD patients and 12 healthy comparison subjects. RESULTS: Spironolactone significantly elevated basal cortisol and ACTH concentrations as well as cortisol secretion after CRH stimulation, but no differential effect between PTSD patients and comparison subjects was detected. CONCLUSIONS: The results indicate intact, but not enhanced, mineralocorticoid receptor function in PTSD. The study's experimental conditions did not allow determination of whether other compensatory factors might have masked the putative mineralocorticoid receptor changes. 相似文献
80.
Agnes B. Renner Ulrich Kellner Elke Cropp Michael H. Foerster 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2006,244(11):1467-1473
Background Only limited data exist on the incidence of negative electroretinograms (ERG) in clinical practice. The purpose of this study
is therefore to determine the incidence and clinical causes of a negative ERG in a tertiary care centre focused on inherited
and acquired retinal degenerations.
Methods All ERGs recorded (in accordance with ISCEV standards) in our electrophysiological laboratory from 1992 to 2004 were retrospectively
reviewed. The negative ERGs (criterion: ERG with b:a wave ratio≤1 in the scotopic standard combined response in at least one
eye) were analysed in the context of further clinical results. The photopic ON- and OFF-responses were recorded with long
duration (200 ms) stimuli.
Results A total of 1999 ERGs from 1644 patients were performed during the study period. 47/1644 patients (2.9%) presented with a negative
ERG and were included in the study. Clinical diagnoses included inherited retinal dystrophies [X-linked congenital retinoschisis
(XRS) (n=17), congenital stationary night blindness (CSNB) (n=6), retinitis pigmentosa (RP) (n=6), cone (-rod) dystrophy (n=5), choroideremia (n=1), Müller cell sheen dystrophy (MCSD) (n=1)] and acquired retinopathies (melanoma-associated retinopathy (MAR) (n=1), vigabatrin retinotoxicity (n=1)). In nine patients a definitive diagnosis could not be established. Unilateral negative ERGs were seen in 10/37 patients
where ERG was bilaterally recorded. The fellow eye presented with a b:a wave ratio >1 (8 eyes) or ERG responses were not detectable
(2 eyes). Photopic ON- and OFF-responses were recorded in 38 eyes of 29 patients and 32/38 eyes presented with a negative
ERG. The ON-response was reduced in 25/32 eyes, whereas the OFF-response was reduced in only 11/32 eyes.
Conclusions The incidence of a negative ERG can differ between the laboratories depending on the causes for ERG recording and was in our
laboratory 2.9% in a consecutive series of patients with inherited or acquired retinal degenerations. A disorder characteristically
associated with negative ERG (e.g. XRS, CSNB, MAR) was diagnosed in 53% of these patients, whereas in 47% the negative ERG
indicated an unexpected post-receptoral dysfunction, e.g. in cone (-rod) dystrophy or RP. The ON-bipolar pathway was affected
in most cases.
Presented in part at the 103rd annual meeting of the German Society of Ophthalmology (DOG), September 2005, Berlin, Germany.
Supported in part by the Deutsche Forschungsgemeinschaft, Bonn, Germany (grant no.: Ke442/11-1,2). 相似文献