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Left main coronary atherosclerosis. I. Clinico-pathological study   总被引:2,自引:0,他引:2  
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Summary Six patients with coronary arterial lesions due to Kawasaki disease underwent aortocoronary by-pass grafting at our institute. Before surgery, all of them had been closely monitored for some years by means of selective coronary arteriography, thallium myocardial imaging, electrocardiography (treadmill and/or Holter), and two-dimensional echo cardiography. Based on this experience, we propose the following guidelines as an indication for aortocoronary by-pass in such patients. First, the following three conditions should be satisfied: 1) The progress of coronary arterial lesions has been documented by serial selective coronary arteriography; 2) redistribution to the perfusion defect has been detected on the delayed image in myocardial imaging; 3) no coronary arterial lesions distal to the graft site have been detected by coronary angiography. When these three conditions are satisfied, at least one of the following conditions must apply: 1) Localized stenosis in the left main trunk has progressed to critical stenosis; 2) there is occlusion of two or more vessels; 3) collateral vessels connecting to the peripheral portion of an occluded coronary artery arise from the peripheral part of a vessel with progressive localized stenosis; 4) progressive localized stenosis or critical stenosis has developed in the left anterior descending artery, in addition to significant stenosis in the right coronary artery.  相似文献   
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We investigated the anti-tumor effects of Verbena officinalis extract on H22 tumor-bearing mice and its effect on immune function. Mice model of H22 solid tumor was established, the mice were divided into five groups and administered the extract, later, tumors were removed and inhibition rates were calculated; spleens were removed and spleen indices were calculated, and the sheep red blood cell-delayed-type hypersensitivity (SRBC-DTH) and the serum hemolysin level were determined. The Verbena officinalis extract had anti-tumor effect, with the inhibition rate reaching 38.78%, it also increased the spleen index to a certain extent, in addition, the changes in DTA and HA were not obvious compared with the model group. The Verbena officinalis extract had in vivo anti-tumor effect, while causing no damage on the immune function.  相似文献   
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We studied the in vitro anti-tumor activity of Bidens Bipinnata L. extract. MTT assay was used to investigate the inhibitory effect of different concentrations of the extracts on human hepatocellular carcinoma (HepG2) cell lines and human cervical carcinoma (Hela) cell lines, and the IC50 values were calculated. The Bidens Bipinnata L. extract had different degrees of inhibitory effects on these two cells, and when exposure time was 48 h, the inhibition rate reached its peak, with IC50 values of 14.80 µg/mL and 13.50 µg/mL respectively. The Bidens Bipinnata L. extract had a good inhibitory effect on human HepG2 cell lines and Hela cell lines, and thus has certain development prospects.  相似文献   
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BackgroundPallister-Killian syndrome (PKS) is a rare disorder caused by the mosaic tetrasomy of chromosome 12p, and is characterized by facial dysmorphism, developmental delay, hypotonia and seizures.ResultsWe report a patient with PKS showing unique polymicrogyria with calcification. He had delayed development and dysmorphic facial features including frontal bossing, hypertelorism, and high arched palate at 6 months of age. Neuroimaging revealed unilateral polymicrogyria with spot calcifications, which predominantly affected the right perisylvian region. Chromosome G-banding showed the karyotype 46,XY, however, array-based comparative genomic hybridization analysis showed mosaic duplication of chromosome 12p, in which CCND2, which encodes cyclin D2 and is a downstream mediator of PI3K-AKT pathway, is located. Supernumerary chromosome of 12p was detected in 58% of buccal mucosa cells by the interphase fluorescence in situ hybridization analysis using chromosome 12 centromere-specific D12Z3 probe. The diagnosis of PKS was made based on distinctive clinical features of our patient and the results of cytogenetic analyses.ConclusionThis report is, to our knowledge, the first case of a patient with PKS who clearly demonstrates polymicrogyria colocalized with calcifications, as shown by CT scans and MRI, and suggests that a patient with PKS could show structural brain anomalies with calcification. We assume that somatic mosaicism of tetrasomy could cause asymmetrical polymicrogyria in our patient, and speculate that increased dosages of CCND2 at chromosome 12p might be involved in the abnormal neuronal migration in PKS.  相似文献   
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ObjectivesUndetectable or low-level hepatitis B virus (HBV) DNA and drug resistance mutations in patients may increase the risk of HBV transmission or cause active viral replication and other clinical problems. Here, we established a highly sensitive and practical method for HBV and drug resistance detection using a polymerase chain reaction (PCR) -based CRISPR-Cas13a detection system (referred to as PCR-CRISPR) and evaluated its detection capability using clinical samples.MethodsSpecific CRISPR RNAs (crRNAs) are designed for HBV DNA detection and YMDD (tyrosine-methionine-aspartate-aspartate) variant identification. The HBV DNA was detected in 312 serum samples for HBV diagnosis using quantification PCR (qPCR) and PCR-CRISPR. Additionally, 424 serum samples for YMDD testing were detected by qPCR, direct sequencing, and our assay.ResultsUsing PCR-CRISPR, one copy per test of HBV DNA was detected with HBV-1 crRNA in 15 min after PCR amplification. Consistent results with qPCR were observed for 302 samples, while the remaining 10 samples with low-level HBV DNA were detectable by PCR-CRISPR and droplet digital PCR but not by qPCR. PCR-CRISPR diagnosed all 412 drug-resistant samples detected by the YMDD detection qPCR kit and direct sequencing, as well as the other 12 drug-resistant samples with low-level HBV DNA undetectable by qPCR and direct sequencing.ConclusionsWe developed a novel PCR-CRISPR method for highly sensitive and specific detection of HBV DNA and drug resistance mutations. One copy per test for HBV DNA and YMDD drug resistance mutations could be detected. This method has wide application prospects for the early detection of HBV infection, drug resistance monitoring and treatment guidance.  相似文献   
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目的 探讨无托槽隐形矫治器设计平面导板,对上中切牙压低效率的影响及支抗前磨牙、磨牙的变化,以期对无托槽隐形矫治器设计平面导板矫治深覆(牙合)提供参考.方法 分别选取无托槽隐形矫治器设计平面导板和无平面导板矫治深覆(牙合)的病例各6例,两组均设计上中切牙不少于0.7mm的压低,通过前牙压低矫正深覆(牙合).前磨牙及磨牙作为支抗牙不设计移动.以腭穹窿为参照,重叠设计压低前后的数字化模型,比较两组上颌中切牙压低效率的差异,以及两组支抗前磨牙和磨牙的差异.结果 平面导板组上中切牙压低效率为33%,无平面导板组上中切牙压低效率为8%,二者的差异无统计学意义(P>0.05);平面导板组第一前磨牙、第二前磨牙、第一磨牙和第二磨牙分别伸长0.3、0.1、0.2和0.1mm;无平面导板组第一前磨牙、第二前磨牙、第一磨牙和第二磨牙分别压低0.0、0.2、0.1和0.1mm,两组的差异均有统计学意义(P<0.05);平面导板组和无平面导板组未设计移动的第一磨牙分别颊倾0.0mm和0.3mm,二者的差异有统计学意义(P<0.05).结论 无托槽隐形矫治器设计平面导板对上颌中切牙的压低无明显影响,但能有效伸长支抗前磨牙及磨牙,克服无托槽隐形矫治器"(牙合)垫效应"造成的后牙压低,并维持磨牙水平向的位置,对深覆(牙合)的矫正发挥一定作用.  相似文献   
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