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21.
Objective—To compare cardiac output measured by the transoesophageal Doppler and thermodilution techniques.

Design—Prospective direct comparison of paired measurements by both techniques in each patient.

Setting—Intensive care unit in a cardiovascular centre.

Patients—65 patients after open heart surgery (mean (SD) age 53 (12) years).

Interventions—Cardiac output was measured simultaneously by the transoesophageal Doppler and thermodilution techniques. Cardiac output was measured again after a mechanical intervention or volume loading.

Results—The limits of agreement were −2·53 to +0·83 1·min−1 for cardiac output measured by the Doppler and thermodilution techniques. This suggests that the Doppler method alone would not be suitable for clinical use. The second measurement of cardiac output by thermodilution was compared with cardiac output estimated from the first and second Doppler measurements and the first thermodilution measurement. The limits of agreement (−0·55 to +0·51 1·min−1) were good enough for clinical use.

Conclusions—After cardiac output had been measured simultaneously by both the Doppler and thermodilution techniques, subsequent transoesophageal Doppler alone gave a clinically useful measurement of cardiac output.

  相似文献   
22.
We encountered two cases of pulmonary infection by Mycobacterium abscessus (M. abscessus). [Case 1] A 66-year-old man who had been treated for non-tuberculous mycobacterium in the past was admitted because of productive cough. His chest X-ray film showed cavitation and direct microscopy of sputum revealed positive acid-fast bacilli (AFB). He was given rifampicin (RFP), ethambutol (EB), and clarythromycin (CAM), and then his symptoms and radiographic findings improved. [Case 2] A 74-year-old man with multiple myeloma as an underlying disease was admitted because of a cavitation found on chest radiography and a positive result for AFB in his sputum. Standard antituberculous drug therapy with isoniazid (INH), RFP, EB, and pyradinamide (PZA) was initiated and then the chest radiographic findings improved. As M. abscessus was isolated two weeks after the induction of therapy, the therapeutic regimen was changed to another combination therapy consisting of EB, clarithromycin (CAM) and ciprofloxacin (CPFX), and then his symptoms and radiographic findings were further improved. In both cases, the bacilli found in their sputum were identified as M. abscessus by DNA hybridization. They were completely resistant to all anti-tuberculosis agents and many antibiotics with a high value of MIC. However, their symptoms, radiographic abnormalities and the results of sputum examination improved following chemotherapy. The results obtained by MIC measurement were inconsistent with the clinical outcomes. The measurement of the MIC value of antibiotics do not necessarily predict its therapeutic effect.  相似文献   
23.
β-ureidopropionase (βUP) deficiency is an autosomal recessive disease characterized by N-carbamyl-β-amino aciduria. To date, only 16 genetically confirmed patients with βUP deficiency have been reported. Here, we report on the clinical, biochemical and molecular findings of 13 Japanese βUP deficient patients. In this group of patients, three novel missense mutations (p.G31S, p.E271K, and p.I286T) and a recently described mutation (p.R326Q) were identified. The p.R326Q mutation was detected in all 13 patients with eight patients being homozygous for this mutation. Screening for the p.R326Q mutation in 110 Japanese individuals showed an allele frequency of 0.9 %. Transient expression of mutant βUP enzymes in HEK293 cells showed that the p.E271K and p.R326Q mutations cause profound decreases in activity (≤ 1.3 %). Conversely, βUP enzymes containing the p.G31S and p.I286T mutations possess residual activities of 50 and 70 %, respectively, suggesting we cannot exclude the presence of additional mutations in the non-coding region of the UPB1 gene. Analysis of a human βUP homology model revealed that the effects of the mutations (p.G31S, p.E271K, and p.R326Q) on enzyme activity are most likely linked to improper oligomer assembly. Highly variable phenotypes ranging from neurological involvement (including convulsions and autism) to asymptomatic, were observed in diagnosed patients. High prevalence of p.R326Q in the normal Japanese population indicates that βUP deficiency is not as rare as generally considered and screening for βUP deficiency should be included in diagnosis of patients with unexplained neurological abnormalities.  相似文献   
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A 57-year-old man without underlying diseases presented with fatigue, loss of appetite, and jaundice 1 week after receiving the first dose of the BNT162b2 mRNA coronavirus disease 2019 (COVID-19) vaccine and showed hemolytic anemia with fragmented erythrocytes and severe thrombocytopenia 2 weeks after receiving the vaccine. An a disintegrin-like and metalloproteinase with thrombospondin type 1 motifs 13 (ADAMTS13) activity level of <10% and ADAMTS13 inhibitor positivity confirmed the diagnosis of acquired thrombotic thrombocytopenic purpura (TTP). Combination therapy with plasma exchange, corticosteroid, and rituximab improved the clinical outcome. We herein report the first Japanese case of TTP possibly associated with vaccination. Physicians should be alert for this rare but life-threatening hematological complication following COVID-19 vaccination.  相似文献   
26.
Here, we report a case of traumatic pulmonary pseudocysts (TPPs) coinciding with vertebral fracture. Traumatic pulmonary pseudocysts (TPPs) are rare complications of blunt chest trauma. These clinical images of CT, presenting here, seemed to be valuable because they show the process of pseudocyst formation.  相似文献   
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A rare case of malignant fibrous histiocytoma (MFH) of the ilium was presented and blood-pool scintigraphic images and angiographic images were correlated. Hypervascular tumor and laking of contrast material with arteriovenous shunts were shown by angiography. Intensive tracer accumulation was shown by blood-pool scintigraphy. After radiation therapy and transcatheter arterial embolization of the tumor, tracer accumulation was noticeably reduced. These findings suggested a vascular tumor such as angiosarcoma, but surgery revealed MFH of the bone. Blood-pool scintigraphy was useful in the evaluation of the vascular characteristics of the tumor.  相似文献   
30.
The incidence and characteristics of microbleeds in hemodialysis (HD) patients were investigated to elucidate the clinical significance with T(2)(*)-weighted gradient-echo magnetic resonance (MR) imaging. The 57 patients with chronic renal failure maintained by HD had no previous history of stroke. The control group consisted of 53 patients without previous history of stroke or chronic renal failure. The incidence and the number of microbleeds were assessed in the HD and control groups. The findings of microbleeds with T(2)(*)-weighted gradient-echo MR imaging were compared with those of T(1)- and T(2)-weighted MR imaging in HD patients. The incidence of microbleeds was significantly greater in the HD patients compared with the control patients. T(2)(*)-weighted gradient-echo imaging revealed a total of 44 microbleeds in 11 HD patients. T(2)-weighted imaging demonstrated 13 of 44 microbleeds as hyperintensity, whereas T(1)-weighted imaging demonstrated 12 lesions as hypointensity. T(2)- and T(1)-weighted imagings did not demonstrate any findings in 31 and 32 lesions, respectively. T(2)(*)-weighted gradient-echo MR imaging is effective to detect microbleeds which may be a predictor of intracerebral hemorrhage in HD patients and should be included in the protocol for the study of cerebrovascular disease, because T(2)- and T(1)-weighted MR imaging recognizes microbleeds as lacunar infarction.  相似文献   
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