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31.
32.
Clinical and bacteriological data of 145 inpatients with septicemia, treated at the hospital of Chiba University School of Medicine from 1972 to 1987, were reviewed by dividing them into three stages. (stages I: 1972-76, stage II: 1978-82, stage III: 1983-87) Patients with underlying diseases have been increasing: 91.8% of the total patients in stage III. Among the patients with underlying diseases, malignant and hematological diseases occupied about 60%, and in the other diseases, congenital heart diseases have been increasing in number. As to the organisms isolated, gram positive bacteria have increased, while gram negative bacteria have decreased. In stage III, the rate of gram positive organisms and gram negative ones accounted for 43.1% and 41.2% of all the isolates from the septic patients with malignant & hematological diseases, respectively. In patients with malignant & hematological diseases, alpha-streptococcus, coagulase-negative staphylococcus, and Fusobacterium sp. have been increasing, whereas, Escherichia coli, Enterobacter sp., Klebsiella sp., and Pseudomonas aeruginosa decreasing. In patients with other underlying diseases, S. aureus, CNS, and non Fermenters have been increasing. Among the patients without underlying diseases, gram positive bacteria accounted for the major part. The decrease of gram negative organisms in patients with malignant and hematological diseases may partially depend on the introduction of polymixin B as the drug of gut decontamination. The outcome of septicemia in the patients with malignant & hematological diseases has been markedly improving through all the three stages. During stage III, episode mortality and case mortality rate proved to be 23% and 31%, respectively. The introduction of the third generation cephems has decreased the mortality rate for gram negative organisms and contributed to the improvement of the total prognosis. The prognosis was worst in the case of P. aeruginosa, showing a mortality rate of 50% during stage III. Coincidence rate of blood and other cultures have been largest in the case of P. aeruginosa, so, the drug sensitivity of the strain cultured from other sites is sometimes useful in the choice of antibiotics.  相似文献   
33.
OBJECTIVES: The purpose of this study was to investigate the use of coronary magnetic resonance angiography (MRA) for assessing human epicardial coronary artery vasodilation. BACKGROUND: Coronary vasodilation plays a vital role in the human coronary circulation. Previous studies of epicardial coronary vasodilation have used invasive coronary angiography. Coronary MRA may provide an alternative noninvasive method to directly assess changes in coronary size. METHODS: Thirty-two subjects were studied: 12 patients (age 55 +/- 18 years) and 20 healthy subjects (age 34 +/- 4 years). High-resolution multi-slice spiral coronary MRA (in-plane resolution of 0.52 to 0.75 mm) was performed before and after sublingual nitroglycerin (NTG). Quantitative analysis of coronary vasodilation was performed on cross-sectional images of the right coronary artery (RCA). A time-course analysis of coronary vasodilation was performed in a subset of eight subjects for 30 min after NTG. Signal-to-noise ratio was also measured on the in-plane RCA images. RESULTS: Coronary MRA demonstrated a 23% increase in cross-sectional area after NTG (16.9 +/- 7.8 mm2 to 20.8 +/- 8.9 mm2, p <0.0001), with significant vasodilation between 3 and 15 min after NTG on time-course analysis. The MRA measurements had low interobserver variability (< or =5%) and good correlation with X-ray angiography (r=0.98). The magnitude of vasodilation correlated with baseline cross-sectional area (r=0.52, p=0.03) and age (r=0.40, p=0.019). Post-NTG images also demonstrated a 31% improvement in coronary signal-to-noise ratio (p = 0.002). CONCLUSIONS: Nitroglycerin-enhanced coronary MRA can noninvasively measure coronary artery vasodilation and is a promising noninvasive technique to study coronary vasomotor function.  相似文献   
34.
Herein, a facile in situ solvothermal technique for the synthesis of a CdMoO4/graphene composite photocatalyst is reported. Graphene oxide (GO) was synthesised by an improved Hummers'' method and was further used for the in situ synthesis of graphene via GO reduction and the formation of a CdMoO4 nanowire/graphene composite. The structural phase formation of tetragonal CdMoO4 was confirmed from X-ray diffraction measurements. The small nanoparticle assembled nanowires, prismatic microsphere morphology and crystalline nature of the synthesized material were investigated using field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). Due to its unique morphology and stability, the CdMoO4/graphene composite was used as a photocatalyst for H2O splitting. In comparison to pristine CdMoO4, the CdMoO4/graphene composite showed the best hydrogen evolution rate, i.e. 3624 μmole h−1 g−1, with an apparent quantum yield of 30.5%. The CdMoO4/graphene composite has a higher photocatalytic activity due to the inhibition of charge carrier recombination. H2 production measurements showed that the ternary semiconductor/graphene composite has enhanced photocatalytic activity for H2 generation.

Herein, a facile in situ solvothermal technique for the synthesis of a CdMoO4/graphene composite photocatalyst for hydrogen generation under natural solar light.  相似文献   
35.
Both intravascular ultrasound (IVUS) and optical coherence tomography (OCT) play a crucial role in elucidating the pathophysiology of coronary artery disease (CAD) with the goal to improve patient outcomes of medical and/or interventional CAD management. However, no single intravascular imaging technique has been proven to provide complete and detailed evaluation of all CAD lesions due to some limitations. Although sequential use of multiple modalities may sometimes be performed, there may be issues related to risk, time, and cost. To overcome these problems, several hybrids involving dual-probe combined IVUS-OCT catheters have been developed.The aim of this review article is to demonstrate some limitations of stand-alone imaging devices for evaluation of CAD, summarize the advances in hybrid IVUS-OCT imaging devices, discuss the technical challenges, and present the potential value in the clinical setting, especially in patients receiving medical or interventional CAD management.  相似文献   
36.
OBJECTIVES: The goal of the present study was to compare the accuracy of in vivo tissue characterization obtained by intravascular ultrasound (IVUS) radiofrequency (RF) data analysis, known as Virtual Histology (VH), to the in vitro histopathology of coronary atherosclerotic plaques obtained by directional coronary atherectomy. BACKGROUND: Vulnerable plaque leading to acute coronary syndrome (ACS) has been associated with specific plaque composition, and its characterization is an important clinical focus. METHODS: Virtual histology IVUS images were performed before and after a single debulking cut using directional coronary atherectomy. Debulking region of in vivo histology image was predicted by comparing pre- and post-debulking VH images. Analysis of VH images with the corresponding tissue cross section was performed. RESULTS: Fifteen stable angina pectoris (AP) and 15 ACS patients were enrolled. The results of IVUS RF data analysis correlated well with histopathologic examination (predictive accuracy from all patients data: 87.1% for fibrous, 87.1% for fibro-fatty, 88.3% for necrotic core, and 96.5% for dense calcium regions, respectively). In addition, the frequency of necrotic core was significantly higher in the ACS group than in the stable AP group (in vitro histopathology: 22.6% vs. 12.6%, p = 0.02; in vivo virtual histology: 24.5% vs. 10.4%, p = 0.002). CONCLUSIONS: Correlation of in vivo IVUS RF data analysis with histopathology shows a high accuracy. In vivo IVUS RF data analysis is a useful modality for the classification of different types of coronary components, and may play an important role in the detection of vulnerable plaque.  相似文献   
37.
A 49-year-old female presented with a 1-month history of cough and low-grade fever. Echocardiography showed a large mass in the right ventricle and percutaneous right ventricular endomyocardial biopsy provided the histologic diagnosis. Despite radiotherapy and chemotherapy, the patient died. At autopsy, the metastatic deposit in the heart was larger than the primary cervical carcinoma.  相似文献   
38.
We have previously reported that prostaglandin F(2alpha) (PGF(2alpha)) stimulates interleukin-6 (IL-6), a potent bone resorptive agent, through p44/p42 mitogen-activated protein (MAP) kinase in osteoblast-like MC3T3-E1 cells. In the present study, we investigated whether Rho-kinase is implicated in the PGF(2alpha)-stimulated IL-6 synthesis in MC3T3-E1 cells. PGF(2alpha) time-dependently induced the phosphorylation of myosin phosphatase targeting subunit (MYPT-1), a Rho-kinase substrate. Y27632, a specific Rho-kinase inhibitor, significantly reduced the PGF(2alpha)-stimulated IL-6 synthesis as well as the MYPT-1 phosphorylation. Fasudil, another inhibitor of Rho-kinase, suppressed the PGF(2alpha)-stimulated IL-6 synthesis. Y27632 and fasudil failed to affect the PGF(2alpha)-induced phosphorylation of p44/p42 MAP kinase. SB203580 and BIRB0796, potent inhibitors of p38 MAP kinase, suppressed the IL-6 synthesis induced by PGF(2alpha). While SP600125, an inhibitor of stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK), failed to reduce the synthesis. Y27632 as well as fasudil attenuated the PGF(2alpha)-induced phosphorylation of p38 MAP kinase. These results strongly suggest that Rho-kinase regulates PGF(2alpha)-stimulated IL-6 synthesis via p38 MAP kinase activation in osteoblasts.  相似文献   
39.
In rheumatoid arthritis (RA), osteoclastic bone resorption causes structural joint damage as well as periarticular and systemic bone loss. Periarticular bone loss is one of the earliest indices of RA, often preceding the onset of clinical symptoms via largely unknown mechanisms. Excessive osteoclastogenesis induced by receptor activator of NF-κB ligand (RANKL) expressed by synovial fibroblasts causes joint erosion, whereas the role of RANKL expressed by lymphocytes in various types of bone damage has yet to be elucidated. In the bone marrow of arthritic mice, we found an increase in the number of RANKL-expressing plasma cells, which displayed an ability to induce osteoclastogenesis in vitro. Genetic ablation of RANKL in B-lineage cells resulted in amelioration of periarticular bone loss, but not of articular erosion or systemic bone loss, in autoimmune arthritis. We also show conclusive evidence for the critical contribution of synovial fibroblast RANKL to joint erosion in collagen-induced arthritis on the arthritogenic DBA/1J background. This study highlights the importance of plasma-cell RANKL in periarticular bone loss in arthritis and provides mechanistic insight into the early manifestation of bone lesion induced by autoimmunity.  相似文献   
40.
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