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31.
Summary During recent years, a significantly increased incidence of acute mastoiditis was observed at the University Children's Hospital, Tübingen, Germany (1975–1979: 1.4 patients/year; 1987–1992: 4.2 patients/year; p<0.05). We therefore reviewed the records of all patients with acute mastoiditis (n=58) that had been treated at the Children's Hospital between 1975 and 1992 and at the Clinic of Otorhinolaryngology between 1978 and 1992. The male to female ratio was 1.8:1 and 60.4% of the patients were younger than 24 months. Retroauricular swelling was more often observed (n=49) than protrusion of the pinna (n=45) and retroauricular redness (n=38).Streptococcus pneumoniae was the most frequently isolated pathogen. Several factors predisposing for the development of acute mastoiditis were identified. These included withholding antimicrobials for treatment of the preceding episode of otitis media; use of suboptimal agents for therapy of otitis media (penicillin and, possibly, erythromycin ethylsuccinate); and insufficient duration of treatment.
Akute Mastoiditis — wieder ein aktuelles Problem
Zusammenfassung In den letzten Jahren wurde an der Univ.-Kinderklinik Tübingen eine signifikante Zunahme der Inzidenz der akuten Mastoiditis beobachtet (1975–1979: 1,4 Patienten/Jahr; 1987–1992: 4,2 Patienten/Jahr; p<0,05). Wir analysierten daher die Krankengeschichten aller Patienten mit akuter Mastoiditis (n=58), die zwischen 1975 und 1992 an der Universitäts-Kinderklinik und zwischen 1978 und 1992 an der Universitäts-Hals-Nasen-Ohrenklinik behandelt worden waren. Das Verhältnis von Jungen zu Mädchen betrug 1,8:1, und 60,4% der Patienten waren jünger als 24 Monate. Eine retroaurikuläre Schwellung wurde häufiger beobachtet (n=48) als ein abstehendes Ohr (n=45) und eine retroaurikuläre Rötung (n=38).Streptococcus pneumoniae war der häufigste Erreger. Mehrere für das Auftreten einer akuten Mastoiditis prädisponierende Faktoren wurden gefunden: die Nichtbehandlung der vorausgegangenen Otitis media mit Antibiotika, der Einsatz suboptimaler Antibiotika (Penicillin und möglicherweise Erythromycin-Ethylsuccinat) für die Otitis-Behandlung und eine ungenügende Therapiedauer.
  相似文献   
32.
BACKGROUND AND AIMS: The aim of this work was to test the feasibility of using a bipolar low thermal acting system inducing collagenic sealing but not protein coagulation to secure hepatic parenchyma cutting. MATERIALS AND METHODS: Thirty consecutive hepatectomies were carried out using kellyclasy plus ligatures and clips (controls), while the following 50 hepatectomies used kellyclasy plus bipolar vessels sealer (BVS). Blood loss, duration of hepatic pedicle clamping, length of hospital stay, and complications were recorded. RESULTS: There was no statistically significant difference in blood loss and duration of clamping between controls and BVS. Specific complications (9/21 in the control group vs 1/49 for the BVS group, p<0.00045) and length of hospital stay (14 days in the control group vs 11 days in the BVS group, p<0.014) were statistically lower in BVS group than in the controls, mainly due to prevention of bile duct leakages. CONCLUSIONS: Our data suggest that BVS may be particularly efficient to achieve bilistasis leading to the highest level of safety in performing hepatectomies. Further studies are now needed to confirm its superiority on the classical biliary ducts occlusion techniques.  相似文献   
33.
Chronic allograft nephropathy (CAN) of renal allografts is still the most important cause of graft loss. A subset of these patients have transplant glomerulopathy (TGP), characterized by glomerular basement membrane (GBM) duplications, but of unknown etiology. Recently, a role for the immune system in the pathogenesis of TGP has been suggested. In 11 of 16 patients with TGP and in 3 of 16 controls with CAN in the absence of TGP we demonstrate circulating antibodies reactive with GBM isolates. The presence of anti-GBM antibodies was associated with the number of rejection episodes prior to diagnosis of TGP. Sera from the TGP patients also reacted with highly purified GBM heparan sulphate proteoglycans (HSPG). Indirect immunofluorescence with patient IgG showed a GBM-like staining pattern and colocalization with the HSPGs perlecan and especially agrin. Using patient IgG, we affinity purified the antigen and identified it as agrin. Reactivity with agrin was found in 7 of 16 (44%) of patients with TGP and in 7 of 11 (64%) patients with anti-GBM reactivity. In conclusion, we have identified a humoral response against the GBM-HSPG agrin in patients with TGP, which may play a role in the pathogenesis of TGP.  相似文献   
34.
We report the results of a retrospective review of the outpatient pretransplantation workup for United Network for Organ Sharing (UNOS) 3 patients adopted at a liver transplantation (LT) center and illustrate the efficiency indicators used for quality evaluation and cost-analysis. A single-center, pre-LT evaluation workup was performed on an outpatient basis at a cost per patient evaluation of 2,770 Euros (). Objective measures were: the number of patients admitted to and excluded from each phase of the algorithm; the rate of patients admitted to pre-LT evaluation out of the total of referred patients (the referral efficiency rate); the rate of waitlisted patients out of those admitted to pre-LT evaluation (the evaluation efficiency rate); the rate of waitlisted patients out of those referred for LT (the process efficiency rate); and the cost per waitlisted patient, as the ratio of the cost per patient evaluation to the evaluation efficiency rate. From January 1, 1996, to October 1, 2004, 1,837 patients were referred for LT on an outpatient basis. Based on preemptive evaluation of the available clinical data, 412 patients (22.4%) were excluded from pre-LT evaluation and 1,425 (77.6%) were admitted to preliminary consultation. Among these, 603 (42.3%) were excluded from and 822 (57.7%) were admitted to pre-LT evaluation with a referral efficiency rate of 44.7% (822 of 1,837). Out of the patients evaluated for LT, 484 were waitlisted with a cost-utility and evaluation efficiency rate of 58.8% each (484 of 822). Of the 1,837 patients originally addressed for LT 484 were waitlisted, yielding a process efficiency rate of 26.3% (484 of 1,837) and a cost per waitlisted patient of 4,710.8. In conclusion, the 3 indicators allowed monitoring of the efficiency of the pre-LT evaluation algorithm. The current process efficiency rate at our center is low (26.3%), but avoiding early referrals we might increase it to 31.6%, with a 12% net saving on costs per waitlisted patient (from 4,710.8 to 4,165.4).  相似文献   
35.
36.
The pulmonary vascular responses to histamine, epinephrine, and norepinephrine demonstrate tachyphylaxis following repetitive exposure in the isolated blood-perfused cat lung. In the present study, we tested the hypothesis that this phenomenon was related to a change in the balance of antagonistic receptor activity. The protocol consisted of 5 consecutive dose-response maneuvers (DR I to V) to 1 amine in each animal separated by 1 h. Once the loss of the initial vasoconstrictor activity had occurred (DR I to IV), the animal was given a receptor blocking agent, either the beta blocker propranolol or the H2 blocker cimetidine, prior to a final dose-response maneuver (DR V). The dose-response relationships were analyzed in terms of 3 parameters: maximum response, slope, and ED50. All the experiments with norepinephrine (n = 6), epinephrine (n = 10), and histamine (n = 25) demonstrated a progressive loss of vasopressor activity as shown by reductions in the maximum response and slope between DR I to IV. In addition, histamine demonstrated a significant increase in ED50 from DR I to IV, which suggested a loss of sensitivity. The loss of vasoconstrictor activity to histamine and the catecholamines was restored by the administration of propranolol prior to DR V. In contrast, cimetidine did not restore the initial vasopressor activity of histamine. The loss of reactivity to histamine was not secondary to changes in circulating catecholamine levels, because the plasma catecholamine levels before DR I and immediately following DR V in a subset of animals (n = 5) were within the reported normal range for this species.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
37.
The contribution of (18)F-FDG uptake by endothelial cells to uptake values measured by PET in various tissues is as yet unclear. We therefore sought to characterize (18)F-FDG uptake in an in vitro model of human endothelial cells. METHODS: Commercially obtained human umbilical vein endothelial cells (HUVECs) were seeded in 6-multiwell plates 48-96 h before incubation with 1-2 MBq (18)F-FDG per well. Radioactivity measurements were performed after washing and mechanical dissolvation of the cellular monolayers. Cellular (18)F-FDG uptake was referred to protein concentration. This experimental protocol was subsequently varied to study the effect of different parameters of interest. Furthermore, radio-thin-layer chromatography was used to identify intracellular (18)F-FDG metabolites. (18)F-FDG uptake in HUVECs was compared with that by a human monocyte-macrophage (HMM) preparation and by glioblastoma cells (GLIOs) under identical experimental conditions. RESULTS: (18)F-FDG accumulated in HUVECs in a time-dependent manner and was trapped mainly as (18)F-FDG-6-phosphate and (18)F-FDG-1,6-diphosphate. Unlabeled glucose and cytochalasin B competitively inhibited (18)F-FDG uptake, whereas phlorizin had no significant effect. Glucose deprivation significantly enhanced (18)F-FDG uptake by a factor of 2.7, whereas sodium depletion had no significant influence. HUVECs treated with vascular endothelial growth factor (VEGF) showed a significant 82% increase in (18)F-FDG accumulation after a 2-h exposure to 50 ng/mL VEGF. (18)F-FDG uptake in HUVECs was significantly higher than that in HMMs and in the range of the uptake values measured in GLIOs. CONCLUSION: (18)F-FDG accumulates in HUVECs by mechanisms analogous to those in neoplastic cells or neurons. VEGF significantly stimulates endothelial (18)F-FDG uptake. The observed differences in (18)F-FDG uptake between HUVECs, HMMs, and GLIOs are difficult to extrapolate to in vivo conditions but stimulate further studies on the contribution of endothelial (18)F-FDG uptake to the overall uptake of that tracer in neoplastic or vascular lesions.  相似文献   
38.
To compare rest-injected thallium-201 (Tl) redistribution and resting technetium-99m methoxyisobutylisonitrile (99mTc-MIBI) myocardial uptake in chronic coronary artery disease (CAD), 15 patients with angiographically proven CAD and left ventricular (LV) dysfunction (ejection fraction 34%±9%) were studied. All patients underwent rest-redistribution Tl and resting 99mTc-MIBI cardiac imaging. Gated 99mTc-MIBI images were also acquired to assess regional LV wall motion (WM). Myocardial segments (n=225) were divided into three groups on the basis of the degree of coronary artery stenosis: group 1 (total occlusion, n=82), group 2 (50%–99% of stenosis, n=84) and group 3 (<50% of stenosis, n=59). WM was significantly worse in groups 1 and 2 compared to group 3 (P<0.001), but no difference was observed between groups 1 and 2. TI and 99mTc-MIBI uptake were significantly lower in groups 1 and 2 compared to group 3 (P < 0.001), and in group 1 compared to group 2 (P<0.001). When TI and 99mTc-MIBI uptake were directly compared, TI uptake was higher than 99mTc-MIBI uptake in group 1 (P<0.001), while no significant difference was observed in groups 2 and 3. Thus, both rest-injected TI redistribution and resting 99mTc-MIBI uptake reflected the severity of coronary artery stenosis in CAD. However, in myocardial segments with total coronary occlusion T1 uptake was significantly higher than 99mTc-MIBI uptake. Our data suggest that rest-injected Tl redistribution cardiac imaging may identify, more accurately than resting 99mTc-MIBI imaging, the presence of viable myocardium in chronic CAD, particularly when the coronary blood flow is severely impaired.  相似文献   
39.
Oligofurostanosides from Asparagus cochinchinensis   总被引:1,自引:0,他引:1  
The aqueous extract of ASPARAGUS COCHINCHINENSIS yielded a new oligofurostanoside 3- O-[alpha- L-rhamnopyranosyl-(1-->4)-beta- D-glucopyranosyl]-26- O-(beta- D-glucopyranosyl)-(25 R)-furosta-5,20-diene,-3beta,26-diol as well as two known furostanosides, methylprotodioscin and pseudoprotodioscin.  相似文献   
40.
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