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排序方式: 共有1114条查询结果,搜索用时 15 毫秒
91.
Frederik T. W. Groenland MD Annemieke C. Ziedses des Plantes BSc Tara Neleman BSc Alessandra Scoccia MD Jurgen M. R. Ligthart RT Karen T. Witberg RN Karim D. Mahmoud MD PhD Rutger-Jan Nuis MD PhD Wijnand K. den Dekker MD PhD Jeroen M. Wilschut MD Roberto Diletti MD PhD Felix Zijlstra MD PhD Nicolas M. Van Mieghem MD PhD Joost Daemen MD PhD 《Catheterization and cardiovascular interventions》2023,102(2):191-199
Background
Dedicated prospective studies investigating high-definition intravascular ultrasound (HD-IVUS)-guided primary percutaneous coronary intervention (PCI) are lacking. The aim of this study was to qualify and quantify culprit lesion plaque characteristics and thrombus using HD-IVUS in patients presenting with ST-segment elevation myocardial infarction (STEMI).Methods
The SPECTRUM study is a prospective, single-center, observational cohort study investigating the impact of HD-IVUS-guided primary PCI in 200 STEMI patients (NCT05007535). The first 100 study patients with a de novo culprit lesion and a per-protocol mandated preintervention pullback directly after vessel wiring were subject to a predefined imaging analysis. Culprit lesion plaque characteristics and different thrombus types were assessed. An IVUS-derived thrombus score, including a 1-point adjudication for a long total thrombus length, long occlusive thrombus length, and large maximum thrombus angle, was developed to differentiate between low (0–1 points) and high (2–3 points) thrombus burden. Optimal cut-off values were obtained using receiver operating characteristic curves.Results
The mean age was 63.5 (±12.1) years and 69 (69.0%) patients were male. The median culprit lesion length was 33.5 (22.8–38.9) mm. Plaque rupture and convex calcium were appreciated in 48 (48.0%) and 10 (10.0%) patients, respectively. Thrombus was observed in 91 (91.0%) patients (acute thrombus 3.3%; subacute thrombus 100.0%; organized thrombus 22.0%). High IVUS-derived thrombus burden was present in 37/91 (40.7%) patients and was associated with higher rates of impaired final thrombolysis in myocardial infarction flow (grade 0–2) (27.0% vs. 1.9%, p < 0.001).Conclusions
HD-IVUS in patients presenting with STEMI allows detailed culprit lesion plaque characterization and thrombus grading that may guide tailored PCI. 相似文献92.
Fibroblast growth factor receptor (FGFR) signaling is crucial for neural development and regeneration. Here we investigated the L5 spinal ganglion and the sciatic nerve of intact Fgfr3-deficient mice after nerve injury. Quantification of sensory neurons in the L5 spinal ganglion revealed no significant differences between wild-type and Fgfr3-deficient mice. Seven days after nerve lesion, the normally occurring neuron loss in wild-type mice was not found in Fgfr3-deficient animals, suggesting that FGFR3 signaling is involved in the cell death process. Morphometric analysis of the sciatic nerve showed similar numbers of myelinated axons, but the axonal and myelin diameter was significantly smaller in Fgfr3-deficient mice compared to the wild types. Evaluation of regenerating myelinated axons of the sciatic nerve revealed no differences between both mouse strains 7 days after crush injury. Our results suggest that FGFR3 signaling seems to be involved in processes of damage-induced neuron death and axonal development. 相似文献
93.
B Hellwig B Schelter B Guschlbauer J Timmer C H Lücking 《Clinical neurophysiology》2003,114(8):1462-1467
OBJECTIVE: Coherence analysis of electromyography (EMG) signals in essential tremor (ET) suggests that tremor in the right and left arm is induced by independent central oscillators. The sensorimotor cortex seems to be part of the tremor-generating neuronal network in ET. Here, we investigated using electroencephalography (EEG) whether the independence of central oscillators in ET is supported by the analysis of cortical activity. METHODS: In 8 patients with ET, bilateral hand tremor was activated by wrist extension. EMGs from the wrist flexors and extensors were recorded simultaneously with an EEG. EEG-EMG coherence was estimated for 74 epochs of 60 s duration. RESULTS: In 42.6% of the cases, EEG-EMG coherence at the tremor frequency existed only with the contralateral sensorimotor cortex. However, 21.6% of the tremor-EMGs were coherent with EEG activity over both the contralateral and ipsilateral sensorimotor cortex. Bilateral and exclusively contralateral EEG-EMG coherence could alternate within the same recording. Bilateral EEG-EMG coherence was associated with increased right-left EEG-EEG coherence, increased right-left EMG-EMG coherence as well as with increased tremor strength. CONCLUSIONS: In ET, central oscillators in the right and left brain are not entirely independent of each other. They may dynamically synchronise, presumably by interhemispheric coupling via the corpus callosum. 相似文献
94.
95.
Masato Hashimoto MD PhD Kenji Ohtsuka MD PhD Hidenari Akiba MD Kuniaki Harada RT 《American journal of ophthalmology》1998,125(6):881-882
Purpose: To describe the thin-slice magnetic resonance imaging features of vascular compressive oculomotor nerve paresis.Methods: We performed thin-slice (2 mm thick) magnetic resonance imaging of the brainstem in a 74-year-old woman with right partial oculomotor nerve paresis using spoiled gradient recalled acquisition in the steady state.Results: Thin-slice magnetic resonance images disclosed that the right oculomotor nerve was compressed and dislocated superiorly and laterally by the tortuous basilar artery. No other abnormalities were observed.Conclusion: This is the first case report of vascular compressive oculomotor nerve paresis disclosed by thin-slice magnetic resonance imaging. 相似文献
96.
The genetic defect in the p67phox-deficient form of chronic granulomatous disease (CGD) follows an autosomal recessive pattern of inheritance. When genomic DNA from normal individuals is digested with HindIII and probed with p67phox cDNA an allelic restriction fragment length polymorphism (RFLP) of 4.0 kb or 2.3 kb is detected. We cloned and characterized the p67phox gene using the cDNA and sequenced the exon/intron boundaries, mapping 16 exons on the 40-kb gene. The polymorphic region was then sequenced to identify the inheritance pattern of amniocentesis-derived fetal cells by genomic amplification. The proband, a 9-year-old female patient with p67phox-deficient CGD, and her phenotypically normal mother are homozygous for the RFLP marker, whereas the father and two brothers are heterozygous. The fetus was shown to be heterozygous as well, showing it had inherited at least one normal p67phox gene from the father and that it was predicted to have a normal phenotype. Cord blood samples at birth showed normal oxidative function. Amplification allows rapid detection of the inheritance pattern for fetal diagnosis in informative families. We report the genomic structure of p67phox and an amplification-based method for detection of the marker on chromosome 1q25, used here for prenatal diagnosis of CGD. 相似文献
97.
Thomas Falvo DO Lance Grove RT EMT-P Ruth Stachura RN William Zirkin MD 《Academic emergency medicine》2007,14(1):58-62
Objectives
Admission process delays and other throughput inefficiencies are a leading cause of emergency department (ED) overcrowding, ambulance diversion, and patient elopements. Hospital capacity constraints reduce the number of treatment beds available to provide revenue-generating patient services. The objective of this study was to develop a practical method for quantifying the revenues that are potentially lost as a result of patient elopements and ambulance diversion.
Methods
Historical data from 62,588 patient visits to the ED of a 450-bed nonprofit community teaching hospital in central Pennsylvania between July 2004 and June 2005 were used to estimate the value of potential patient visits foregone as a result of ambulance diversion and patients leaving the ED without treatment.
Results
The study hospital may have lost $3,881,506 in net revenue as a result of ambulance diversions and patient elopements from the ED during a 12-month period.
Conclusions
Significant revenue may be foregone as a result of throughput delays that prevent the ED from utilizing its existing bed capacity for additional patient visits. 相似文献
Admission process delays and other throughput inefficiencies are a leading cause of emergency department (ED) overcrowding, ambulance diversion, and patient elopements. Hospital capacity constraints reduce the number of treatment beds available to provide revenue-generating patient services. The objective of this study was to develop a practical method for quantifying the revenues that are potentially lost as a result of patient elopements and ambulance diversion.
Methods
Historical data from 62,588 patient visits to the ED of a 450-bed nonprofit community teaching hospital in central Pennsylvania between July 2004 and June 2005 were used to estimate the value of potential patient visits foregone as a result of ambulance diversion and patients leaving the ED without treatment.
Results
The study hospital may have lost $3,881,506 in net revenue as a result of ambulance diversions and patient elopements from the ED during a 12-month period.
Conclusions
Significant revenue may be foregone as a result of throughput delays that prevent the ED from utilizing its existing bed capacity for additional patient visits. 相似文献
98.
R Timmer J C Koningsberger D W Erkelens J H Thijssen C J Lips H P Koppeschaar 《The Netherlands journal of medicine》1991,38(5-6):199-203
The efficacy of subchronic (3 weeks) treatment with the long-acting somatostatin analogue octreotide was studied in four patients with symptomatic benign insulinoma. No clinical or biochemical effect on serum glucose, insulin, C-peptide or glucagon was observed in all four patients despite clearly detectable serum levels of octreotide. The resistance to octreotide therapy in these patients might be explained by the absence of somatostatin analogue receptors on their tumours. 相似文献
99.
Vrieling A Voskuil DW Bonfrer JM Korse CM van Doorn J Cats A Depla AC Timmer R Witteman BJ van Leeuwen FE Van't Veer LJ Rookus MA Kampman E 《The American journal of clinical nutrition》2007,86(5):1456-1462
BACKGROUND: Higher circulating insulin-like growth factor I (IGF-I) concentrations have been related to a greater risk of cancer. Lycopene intake is inversely associated with cancer risk, and experimental studies have shown that it may affect the IGF system, possibly through an effect on IGF-binding proteins (IGFBPs). OBJECTIVE: The objective of our study was to investigate the effect of an 8-wk supplementation with tomato-derived lycopene (30 mg/d) on serum concentrations of total IGF-I, IGF-II, IGFBP-1, IGFBP-2, and IGFBP-3. DESIGN: We conducted a randomized, placebo-controlled, double-blinded crossover study in 40 men and 31 postmenopausal women with a family history of colorectal cancer, a personal history of colorectal adenoma, or both. RESULTS: Lycopene supplementation significantly (P = 0.01) increased serum IGFBP-1 concentrations in women (median relative difference between serum IGFBP-1 concentrations after lycopene supplementation and after placebo, 21.7%). Serum IGFBP-2 concentrations were higher in both men and women after lycopene supplementation than after placebo, but to a lesser extent (mean relative difference 8.2%; 95% CI: 0.7%, 15.6% in men and 7.8%; 95% CI: -5.0%, 20.6% in women). Total IGF-I, IGF-II, and IGFBP-3 concentrations were not significantly altered by lycopene supplementation. CONCLUSIONS: This is the first study known to show that lycopene supplementation may increase circulating IGFBP-1 and IGFBP-2 concentrations. Because of high interindividual variations in IGFBP-1 and IGFBP-2 effects, these results should be confirmed in larger randomized intervention studies. 相似文献
100.
We have found that the addition of 10 mM inorganic phosphate to DHA in CPD-adenine maintains ATP levels at normal or higher than normal values for six weeks of storage. 2,3-DPG values are slightly lowered by the extra phosphate, but are still maintained at approximately half normal for four weeks by the DHA. The addition of a higher phosphate concentration, 20 mM, to DHA produced lower levels of ATP and 2,3-DPG than those observed with 10 mM phosphate, although both levels were better than in the CPD-adenine control. pH values in this experiment were lowest in the three preservatives containing DHA, probably indicating increased lactate production due to metabolism of this triose sugar, in addition to dextrose present in CPD. 相似文献