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61.
Nguyen Duy Hung Le Thanh Dung Dang Khanh Huyen Ngo Quang Duy Dong-Van He Nguyen Minh Duc 《International journal of medical sciences》2022,19(7):1110
Background: Prior studies have suggested a number of the subjective visual characteristics that help distinguish between spinal meningiomas and schwannomas on magnetic resonance imaging and computed tomography; however, objective quantification of the signal intensity can be useful information. This study assessed whether quantitative magnetic resonance imaging (MRI) signal intensity (SI) measurements could distinguish intradural-extramedullary schwannomas from meningiomas.Methods: From July 2019 to September 2021, 54 patients with intradural-extramedullary tumors (37 meningiomas and 17 schwannomas) underwent surgery, and tumors were verified pathologically. Defined regions of interest were used to quantify SI values on T1- (T1W) and T2-weighted images (T2W). Receiver operating characteristic curve analysis was used to obtain cutoff values and calculate the area under the curve (AUC), sensitivity (SE), specificity (SP), positive predictive value (PPV), and negative predictive value (NPV).Results: Both Maximum (T2max) and mean (T2mean) T2W SI values demonstrated outstanding (AUC: 0.91) abilities to differentiate meningiomas from schwannomas with Se, Sp, PPV, and NPV values of 94.6%, 70.6%, 87.5%, and 85.7%, respectively, for T2max and 81.1%, 88.2%, 93.8%, and 68.2% for T2mean. The maximum SI value on contrast-enhanced T1W (T1CEmax) and the T2W tumor: fat SI ratio (rTF) demonstrated acceptable abilities (AUC: 0.73 and 0.79, respectively) to differentiate meningiomas from schwannomas with Se, Sp, PPV, and NPV values of 94.6%, 70.6%, 87.5%, and 85.7%, respectively, for T1CEmax and 81.1%, 88.2%, 93.8%, and 68.2% for rTF.Conclusions: Quantitative SI values (T2max, T2mean, T2min, T1CEmax, rTF) can be used to differentiate intradural-extramedullary schwannomas from meningiomas. 相似文献
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①目的在临床状态下验证Hatle公式在功能正常的二尖瓣位双叶机械瓣应用的合理性。②方法利用多普勒超声测量116例接受CarboMedics人工二尖瓣置换病人的二尖瓣瓣口舒张期前向血流和瓣口面积,并与产品标定的瓣口面积相比较。③结果用Hatle公式估测的瓣口面积和其标定的瓣口面积之间无显著相关性(r=0.23,P>0.05);压差半降时间与舒张期二尖瓣瓣口最大流速(r=0.77,P<0.001)、R-R间期(r=0.70,P<0.01)、舒张期充盈时间(r=0.68,P<0.01)、二尖瓣瓣口流率(r=0.55,P<0.05)及每搏量(r=0.50,P<0.05)均存在较密切的关系,而与瓣口面积存在极差的相关性(r=0.09,P>0.05)。④结论在功能正常的二尖瓣位双叶机械瓣,压差半降时间更多地受到瓣膜外因素而不是瓣口面积的影响,Hatle公式不适宜应用于此种状态下 相似文献
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大鼠脂肪条带结构针刺镇痛效应特异性的生物学基础 总被引:2,自引:2,他引:0
目的:观察大鼠脂肪条带结构针刺镇痛效应特异性的生物学基础。方法:选择大鼠胃经沿线脂肪条带结构上后三里以及脂肪条带结构旁两个对照位点(A1、A2),分别进行针刺,针刺结束后立即断头处死,分离出胃经沿线脂肪条带结构,制备匀浆液,采用放免法测定样本中的β内啡肽(βEP)、强啡肽A(DynA)、P物质(SP)含量。结果:βEP针刺后三里(19.08±7.42)与针刺A1、A2位点(2.27±1.99)经成组t检验比较,两者差异显著(t=5.5374,P<0.01)。DynA针刺后三里(23.08±8.61)与针刺A1、A2位点(2.19±1.81)经成组t检验比较,两者差异显著(t=5.8194,P<0.01);SP针刺后三里(1.57±0.49)与针刺A1、A2位点(1.05±0.60)经成组t检验比较,两者差异不显著(t=1.6330,P>0.05)。结论:针刺正常大鼠后三里腧穴,可使胃经沿线脂肪条带结构上特异性针刺镇痛效应物质βEP、DynA含量升高。 相似文献
66.
Notch signaling plays an essential role in development as well as cancer. We have previously shown that Notch3 is important for lung cancer growth and survival. Notch receptors are activated through the interaction with their ligands, resulting in proteolytic cleavage of the receptors. This interaction is modulated by Fringe, a family of fucose-specific β1,3 N-acetylglucosaminyltransferases that modify the extracellular subunit of Notch receptors. Studies in developmental models showed that Fringe enhances Notch’s response to Delta ligands at the expense of Jagged ligands. We observed that Manic Fringe expression is down-regulated in lung cancer. Since Jagged1, a known ligand for Notch3, is often over-expressed in lung cancer, we hypothesized that Fringe negatively regulates Notch3 activation. In this study, we show that re-expression of Manic Fringe down-regulates Notch3 target genes HES1 and HeyL and reduces tumor phenotype in vitro and in vivo. The mechanism for this phenomenon appears to be related to modulation of Notch3 protein stability. Proteasome inhibition reverses Manic Fringe-induced protein turnover. Taken together, our data provide the first evidence that Manic Fringe functions as a tumor suppressor in the lung and that the mechanism of its anti-tumor activity is mediated by inhibition of Notch3 activation. 相似文献
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Liang Jiang Xiao Guang Liu Hui Shu Yuan Shao Min Yang Jie Li Feng Wei Chen Liu Lei Dang Zhong Jun Liu 《The spine journal》2014,14(6):944-954
Background contextVertebral hemangiomas (VHs) are called benign tumors but are actually just vascular malformations. The diagnosis and treatment for aggressive VHs is still controversial, due to their rarity.PurposeTo evaluate the safety and efficiency of the present diagnostic methods and treatment choices.Study designA retrospective study of aggressive VHs with neurologic deficit.Patients sampleA total of 29 consecutive aggressive VH cases were diagnosed and treated in our department since 2001.Outcome measuresWe routinely took anteroposterior and lateral spinal roentgenograms, computed tomography, and magnetic resonance images.MethodsTrocar biopsy is indicated in suspected malignant cases. Radiotherapy was usually our first choice if the neurologic deficit was mild or developed slowly. Surgery was indicated if the neurologic deficit was severe or developed quickly or if the radiotherapy was not effective.ResultsThis series included 12 males and 17 females, and the mean age at diagnosis was 44.0 years (range, 21–72 years). Ten patients had radiculopathy, 1 had cauda equina syndrome, and 18 cases had myelopathy. Twenty-one cases had lesions in the thoracic spine, 5 in the lumbar, and 3 in the cervical region. Eleven cases had untypical image findings, including five cases with pathologic vertebral fracture. The neurologic compression came from only epidural soft tumor mass in 18 cases, whereas it came from both bony compression and soft lesion in the other 11 cases. Ten cases had radiotherapy alone, but two failed and had surgery later. Twenty-one cases had surgery. In the 12 cases having surgical decompression without vertebroplasty, the average estimated blood loss was 1900 mL, and it was 1093 mL for the eight cases having decompression with vertebroplasty. The average follow-up was 51.1 months (range, 24–133 months). There was no recurrence in those cases with radiotherapy, whereas three had local recurrence in those six cases treated by surgical decompression alone without radiotherapy.ConclusionsIn aggressive VHs, epidural soft-tissue compression was usually the main reason for neurologic deficit. In cases with rapid progressive and/or severe myelopathy, posterior decompression and stabilization could be combined with intraoperative vertebroplasty to reduce blood loss. 相似文献
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Postoperative complications: does intensive care unit staff nursing make a difference? 总被引:5,自引:0,他引:5
Dang D Johantgen ME Pronovost PJ Jenckes MW Bass EB 《Heart & lung : the journal of critical care》2002,31(3):219-228
OBJECTIVE: The purpose of this study was to examine the association between intensive care unit nurse (ICU) staffing and the likelihood of complications for patients undergoing abdominal aortic surgery. DESIGN: The study is a retrospective review of hospital discharge data linked to data on ICU organizational characteristics. SETTING: Research took place in ICUs in non-federal, short-stay hospitals in Maryland. PATIENTS: Study included 2606 patients undergoing abdominal aortic surgery in Maryland between January 1994 and December 1996. Outcome Measures: Outcome measures included cardiac, respiratory, and other complications. RESULTS: Cardiac complications occurred in 13% of patients, respiratory complications occurred in 30%, and other complications occurred in 8% of patients. Multiple logistic regression revealed a statistically significant increased likelihood of respiratory complications (odds ratio [OR], 2.33; 95% confidence interval [CI], 1.50-3.60) in abdominal aortic surgery patients cared for in ICUs with low- versus high-intensity nurse staffing, an increased likelihood of cardiac complications (OR, 1.78; CI, 1.16-2.72) and other complications (OR, 1.74; CI, 1.15-2.63) in ICUs with medium- versus high-intensity nurse staffing, after controlling for patient and organizational characteristics. CONCLUSIONS: Within the range of ICU nurse staffing levels present in Maryland hospitals, decreased nurse staffing was significantly associated with an increased risk of complications in patients undergoing abdominal aortic surgery. 相似文献