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31.
目的:探讨大鼠脑出血后神经功能缺损评分、血肿周围脑组织形态学和含水量的动态变化及蛭龙活血通瘀胶囊的干预作用.方法:将75只大鼠随机分为假手术组、脑出血模型组(简称模型组)、蛭龙活血通瘀胶囊高剂量组(简称“高剂量组”)、蛭龙活血通瘀胶囊中剂量组(简称“中剂量组”)、蛭龙活血通瘀胶囊低剂量组(简称“低剂量组”)各15例.采用自体血注入法制备脑出血大鼠模型.采用Zea Longa5分制法进行神经功能缺损评分,在光镜下观察各组大鼠脑组织形态学改变,干湿重法测脑组织含水量.结果:蛭龙活血通瘀胶囊低、中、高剂量组较模型组神经功能缺损评分降低,神经细胞肿胀程度减轻.与模型组比较,低、中、高剂量组脑含水量均明显下降,差异有统计学意义(P<0.01).与低剂量组比较,中、高剂量组脑含水量均明显下降,差异有统计学意义(P<0.01).结论:蛭龙活血通瘀胶囊能明显减轻脑水肿,改善脑出血大鼠神经功能缺损症状,且存在一定量效关系.  相似文献   
32.
目的:通过对长宁社区腰椎间盘突出症的分布规律、中医证型特点和诊治现状进行调查统计,对其原发病因、中医证型与效应指标之间的关系进行分析.方法:随机取样收集病例500例,采用SPSS 13.0软件包,对患者的症状、体征、舌脉采用K-means聚类分析,再对各种类型进行主成分分析,判定各种类型的代表症状,归纳出基本证型;对每位患者的治法和疗效进行分析.结果:调查收集的LDH常见症状24种,症状出现频率较高的是腰骶疼痛、腰腿疼痛、腰部胀痛、单侧下肢放射痛、单侧下肢麻木,活动后加重;症状出现频率较低的是髋部疼痛、鞍区麻木、大小便失禁.91%的患者首选非手术治疗,疗效达95%以上;辨证分型与X线、CT扫描结果有一定的相关性.结论:肝肾亏虚、气滞血瘀是腰椎间盘突出症的根本病机;X线、CT扫描可作为LDH辨证分型的客观指标之一;非手术治疗为LDH首选治疗,疗效满意.  相似文献   
33.
目的 对北京市朝阳区某学校一起耐药肺结核疫情进行分析,为今后耐药结核病疫情的处置提供参考。方法 对病例进行流行病学调查,对病例密切接触者采用PPD试验、X线胸片和CT相结合的方式筛查。结果 2018年10月—2019年6月,该校共发生36例肺结核病例,发病率为4.5%。其中5例耐多药,3例耐利福平。36例病例分布在四个班,15a班27例、15b班4例、15c班2例、17d班3例。各班发病率分别为56.3%、8.3%、5.7%、7.1%,差异有统计学意义(P<0.01)。8例耐药病例中6例为15a班学生,占耐药病例总数的75.0%。经CT筛查68名密切接触者中确诊23例肺结核患者,检出率33.8%。结论 该起学校聚集性疫情为全国首起耐药肺结核聚集性疫情,首发病例未及时就医,传染源隐匿存在时间长,是导致该起疫情发生的主要原因。疫情处置中开展密切接触者筛查对于及时发现新病例非常重要。  相似文献   
34.
Parameter estimation for nonlinear dynamic system models, represented by ordinary differential equations (ODEs), using noisy and sparse data, is a vital task in many fields. We propose a fast and accurate method, manifold-constrained Gaussian process inference (MAGI), for this task. MAGI uses a Gaussian process model over time series data, explicitly conditioned on the manifold constraint that derivatives of the Gaussian process must satisfy the ODE system. By doing so, we completely bypass the need for numerical integration and achieve substantial savings in computational time. MAGI is also suitable for inference with unobserved system components, which often occur in real experiments. MAGI is distinct from existing approaches as we provide a principled statistical construction under a Bayesian framework, which incorporates the ODE system through the manifold constraint. We demonstrate the accuracy and speed of MAGI using realistic examples based on physical experiments.

Dynamic systems, represented as a set of ordinary differential equations (ODEs), are commonly used to model behaviors in scientific domains, such as gene regulation (1), biological rhythms (2), spread of disease (3), ecology (4), etc. We focus on models specified by a set of ODEsx˙(t)=dx(t)dt=f(x(t),θ,t),t[0,T],[1]where the vector x(t) contains the system outputs that evolve over time t and θ is the vector of model parameters to be estimated from experimental/observational data. When f is nonlinear, solving x(t) given initial conditions x(0) and θ generally requires a numerical integration method, such as Runge–Kutta.Historically, ODEs have mainly been used for conceptual or theoretical understanding rather than data fitting as experimental data were limited. Advances in experimental and data collection techniques have increased the capacity to follow dynamic systems closer to real time. Such data will generally be recorded at discrete times and subject to measurement error. Thus, we assume that we observe y(τ)=x(τ)+ϵ(τ) at a set of observation time points τ with error ϵ governed by noise level σ. Our focus here is inference of θ given y(τ), with emphasis on nonlinear f where specialized methods that exploit a linear structure (e.g., refs. 5 and 6), are not generally applicable. We shall present a coherent, statistically principled framework for dynamic system inference with the help of Gaussian processes (GPs). The key to our method is to restrict the GPs on a manifold that satisfies the ODE system: Thus, we name our method MAGI (manifold-constrained Gaussian process inference). Placing a GP on x(t) facilitates inference of θ without numerical integration, and our explicit manifold constraint is the key idea that addresses the conceptual incompatibility between the GP and the specification of the ODE model, as we shall discuss shortly when overviewing our method. We show that the resulting parameter inference is computationally efficient, statistically principled, and effective in a variety of practical scenarios. MAGI particularly works in the cases when some system component(s) is/are unobserved. To the best of our knowledge, none of the current available software packages that do not use numerical integration can analyze systems with unobserved component(s).  相似文献   
35.
This report shows clinical manifestations and provides aspects of surgical strategy for inflammatory aneurysms due to Takayasu's arteritis. Fourteen cases of inflammatory aneurysms among 81 patients with Takayasu's arteritis who underwent surgery in our institute were reviewed. The patient group consisted of six males and eight females, ages from 20 to 61 (mean 39.6±3.5) years. Aneurysmal lesions were located in the ascending aorta or aortic arch (type I) in six (42.9%) patients and the thoracic and/or abdominal aorta (type II) in six patients (42.9%). Type III distribution was determined for two patients (14.3%). Operative procedures for aneurysms included aortic replacement using prosthetic graft (n=6), aneurysmorraphy (n=1), patch angioplasty (n=1), Hardy operation (n=1), aortic valve replacement (AVR) (n=2), and AVR associated with mesh wrapping or aneurysmorraphy (n=3). Operative mortality was 21.4% (three cases) at initial operation and late deaths were found in five cases. Causes of late deaths included rupture of suture aneurysms, rupture of the aortic aneurysm at other aortic lesions, and sudden death due to acute perivalvular leakage. Aggressive surgical approach prior to rupture is required for cases with progressive aortic dilatation even if inflammation signs appear to be controlled. Careful long-term follow-up using periodical angiogram or computed tomography are essential to the best prognosis in pre- and postoperative periods.  相似文献   
36.
Left main coronary atherosclerosis. I. Clinico-pathological study   总被引:2,自引:0,他引:2  
  相似文献   
37.
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   
38.
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   
39.
40.
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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