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61.
目的探讨化瘀解毒汤对脓毒血症患者APACHEⅡ评分、ISTH DIC评分及外周血树突状细胞表面物质表达水平的影响。方法将66例脓毒症患者随机分为对照组和化瘀解毒组,每组33例。对照组给予抗感染、补充血容量、积极治疗原发疾病、吸氧等综合治疗,化瘀解毒组在上述基础上加用化瘀解毒汤治疗,每日1剂,持续治疗2周。检测血清炎症因子[白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)、降钙素原(PCT)]水平变化,应用急性生理与慢性健康状况评分Ⅱ(APACHEⅡ)、DIC评分评估脓毒症患者病情严重程度,应用流式细胞仪分析树突状细胞相关表面分子CD80、CD83、CD86表达情况,比较临床疗效。结果与治疗前比较,两组血清IL-6、TNF-α、PCT水平均降低(P<0.01),APACHEⅡ评分、ISTH DIC评分均降低(P<0.01),CD80、CD86水平均降低(P<0.01),CD83水平无差异(P>0.05);与对照组比较,化瘀解毒组血清IL-6、TNF-α、PCT水平均较低(P<0.01),APACHEⅡ评分、ISTH DIC评分均较低(P<0.01),CD80、CD86水平均较低(P<0.01),总有效率较高(P<0.01)。结论化瘀解毒汤辅助治疗脓毒血症疗效显著,可有效降低APACHEⅡ评分、ISTH DIC评分,可能与调节外周血树突状细胞表面物质表达有关。  相似文献   
62.
通过查阅历代本草方书等文献,对经典名方中所用甘草药材的名称、基原、产地、采收加工、炮制历史沿革及变迁进行了系统的本草考证,为涉及甘草药材的经典名方开发提供依据。经考证可知,古代甘草入药的主流基原为豆科植物甘草Glycyrrhiza uralensis Fisch.。初以甘肃、陕西所产为最优,唐宋时期扩展至山西、陕西、内蒙古等产地;明清时期核心产区移至内蒙,近现代以来逐步形成内蒙古、甘肃、宁夏三大主产区。历代甘草的主要炮制方法为炙法,唐代之前未提及辅料,唐代出现蜜作为辅料的相关记载,宋代出现蜜炙法,明清时期蜜炙的相关记载进一步增多,并延续至今,形成"炙甘草"的炮制规范。故建议包含甘草药材的经典名方,原方标注为"炙"的,唐代之前可按清炒法进行炮制;唐代及以后处方中标注为"炙"的甘草药材建议按照《中华人民共和国药典》中"炙甘草"的规定进行炮制;标注为"生"或未标注者,当以生品入药。  相似文献   
63.
[目的]采用Meta分析法系统评价补肾壮骨汤对椎体成形术治疗骨质疏松型胸腰椎压缩骨折(OTCF)临床的影响。[方法]以"补肾壮骨汤"为首输关键词,以"椎体成形术""骨质疏松""胸腰椎压缩骨折"等为次输关键词,全面搜索补肾壮骨汤对OTCF患者椎体成形术治疗效果影响的随机对照研究文献,评价纳入研究文献的一般特征,对文献资料所提取的治疗有效率、骨密度、Oswestry功能障碍(ODI)指数、治疗安全性(新发骨折率)等观察指标进行Meta分析处理与分析。[结果]共13篇文献纳入Meta分析范畴,文献总样本量1 037例。分析显示,与对照组相比,治疗组可明显提高临床有效率[OR=4.63,95%CI[2.92,7.36],P0.000 01]、改善骨密度[MD=0.08,95%CI[0.06,0.1],P0.000 01]、降低ODI指数[MD=-2.34,95%CI[-3.49,-1.19],P0.000 01]、降低新发骨折率[OR=0.08,95%CI[0.11,0.44],P0.000 01]。[结论]与单纯椎体成形术治疗相比,补肾壮骨汤辅助椎体成形术在OTCF患者治疗中,可提升患者术后骨密度、改善胸腰椎功能障碍和降低术后新发骨折率,治疗疗效确切。  相似文献   
64.
65.
Conservation laws are considered to be fundamental laws of nature. It has broad applications in many fields, including physics, chemistry, biology, geology, and engineering. Solving the differential equations associated with conservation laws is a major branch in computational mathematics. The recent success of machine learning, especially deep learning in areas such as computer vision and natural language processing, has attracted a lot of attention from the community of computational mathematics and inspired many intriguing works in combining machine learning with traditional methods. In this paper, we are the first to view numerical PDE solvers as an MDP and to use (deep) RL to learn new solvers. As proof of concept, we focus on 1-dimensional scalar conservation laws. We deploy the machinery of deep reinforcement learning to train a policy network that can decide on how the numerical solutions should be approximated in a sequential and spatial-temporal adaptive manner. We will show that the problem of solving conservation laws can be naturally viewed as a sequential decision-making process, and the numerical schemes learned in such a way can easily enforce long-term accuracy. Furthermore, the learned policy network is carefully designed to determine a good local discrete approximation based on the current state of the solution, which essentially makes the proposed method a meta-learning approach. In other words, the proposed method is capable of learning how to discretize for a given situation mimicking human experts. Finally, we will provide details on how the policy network is trained, how well it performs compared with some state-of-the-art numerical solvers such as WENO schemes, and supervised learning based approach L3D and PINN, and how well it generalizes.  相似文献   
66.
目的 探讨ArcCHECK系统在食管癌断层治疗旋转照射和固定野照射计划验证中的应用,总结相关经验。方法 对32例不同部位食管癌分别制作Helical旋转照射和Direct固定野照射验证计划,并通过ArcCHECK测量、分析,对比验证结果通过率。分析靶体积与计划验证通过率的相关性。将靶体积较小的治疗验证计划分别放在ArcCHECK模体中心和外周探测点处,分析验证通过率差异。结果 Helical计划验证通过率高于Direct计划(P<0.01),其靶体积与验证通过率的相关系数分别为-0.364和-0.042,P值分别为0.041和0.819。Helical计划采用3%/2mm标准时,高剂量区放在模体中心和外周探测点处测得的通过率不同(P=0.005),后者通过率更高;采用3%/3mm标准时与Direct计划的3%/3m、3%/2mm标准的相近(P均>0.05)。结论 Helical计划验证通过率普遍高于Direct计划,原因可能与ArcCHECK探测器的角度响应以及因更多参考点受到低剂量辐射而未参与计算有关,另外还可能跟Direct计划对断层治疗剂量控制系统要求更高有关。在Helical验证计划中,当采用3%/3mm标准时,靶体积越大,验证时出现较低通过率的可能性增加,但相关系数较低。验证计划的高剂量区位于模体中心或者探测点处都可以实现计划验证,综合考量建议放在模体等中心处。  相似文献   
67.
ABSTRACT

Objectives: Limited evidence has suggested that cefoperazone-sulbactam causes coagulation disorders and bleeding.

Methods: The authors conducted a retrospective study to compare patients receiving cefoperazone-sulbactam versus those treated with cefoperazone-tazobactam or ceftazidime. Propensity-score matching was used to explore whether treatment with cefoperazone-sulbactam increased the risk of prothrombin time (PT) prolongation, coagulation disorders, and bleeding, or decreased platelets (PLT).

Results: The cohort included 23,242 patients. Among patients receiving cefoperazone-sulbactam, the risk of PT prolongation, coagulation disorders, decreased PLT, and bleeding was 5.3%, 9.2%, 15.7%, and 4.2%, respectively. Propensity-score matching analyses suggested that cefoperazone-sulbactam increased the risk of PT prolongation (aOR 2.26, 95% CI 1.61–3.18), coagulation disorders (aOR 1.81, 95% CI 1.43–2.30), and decreased PLT (aOR 1.46, 95% CI 1.25–1.72), but not increase bleeding (aOR 1.05, 95% CI 0.79–1.40) compared with ceftazidime. Patients receiving cefoperazone-sulbactam had higher risk of PT prolongation (aOR 1.53, 95% CI 1.11–2.10), coagulation disorders (aOR 1.53, 95% CI 1.21–1.95), but not decreased PLT (aOR 0.93, 95% CI 0.81–1.07) or bleeding (aOR 1.11, 95% CI 0.87–1.42), compared with those receiving cefoperazone-tazobactam.

Conclusion: Cefoperazone-sulbactam may be associated with a higher risk of PT prolongation and coagulation disorders compared with cefoperazone-tazobactam and ceftazidime.  相似文献   
68.
Abstract

Background and aim: Capsule retention is the most common adverse event associated with video capsule endoscopy. The use of double-balloon enteroscopy-assisted capsule endoscope retrieval has been increasingly reported in recent years. However, evidence is limited regarding its success rate, associated factors, and subsequent clinical outcomes.

Methods: A systematic review of relevant studies published before January 2019 was performed. Successful retrieval rate and associated factors, rate of endoscopic balloon dilation, and outcomes after double-balloon enteroscopy were summarized and pooled.

Results: Within 154 associated original articles, 12 including 150 cases of capsule retrieval by double-balloon enteroscopy were included. The estimated pooled successful retrieval rate was 86.5% (95% confidence interval, 75.6–95.1%). Anterograde approach and capsules retained in the jejunum or trapped by malignant strictures were associated with a higher successful retrieval rate than the retrograde approach (62/83 [74.7%] vs. 10/38 [26.3%], p?<?.001) and capsules retained in the ileum (41/41 [100.0%] vs. 43/58 [74.1%], p?<?.001) or trapped by benign strictures (21/21 [100.0%] vs. 65/83 [78.3%], p?=?.043). Endoscopic balloon dilation was performed in 38.8% (95% confidence interval, 22.3–56.3%) of patients with benign strictures. Two perforations (1.3%) were reported as severe adverse events after double-balloon enteroscopy. A significantly lower surgery rate was found among cases with successful video capsule removal compared with unsuccessful cases (7.2% vs. 38.5%, p?=?.002).

Conclusions: Double-balloon enteroscopy is feasible and safe for removing retained video capsule endoscopes, and its use could decrease the need for surgery in patients with benign strictures and facilitate subsequent surgery in patients with malignant strictures.  相似文献   
69.
目的 建立裸鼠鼻咽癌转移模型并探讨 E-选择素(ELAM-1)与鼻咽癌转移的相关性。方法 将鼻咽癌5-8F细胞悬液注射于裸鼠左后肢爪垫,观察裸鼠状态、成瘤情况并测量裸鼠体重及移植瘤长短径;采用连续病理切片苏木精-伊红染色观察移植瘤及转移情况,将16只人鼻咽癌荷瘤裸鼠分为转移组和非转移组;采用免疫组织化学法检测两组移植瘤组织中ELAM-1的表达。 结果 16只裸鼠均成瘤,成瘤率为100.0%,其中10只裸鼠出现转移瘤,转移率为62.5%。建模前,两组裸鼠体重差异无统计学意义[(13.83±0.56)g vs (14.62±0.30) g,t=1.026,P=0.071]。建模后4~7周,裸鼠瘤体体积呈指数增长,且转移组移植瘤增长速度较非转移组快,非转移组裸鼠瘤体体积小于转移组[(198.91 ± 163.29) mm3 vs (268.76 ±174.31) mm3t=4.376,P=0.005]。ELAM-1在鼻咽癌裸鼠移植瘤、淋巴结转移灶及远处转移灶中的表达均为阳性,主要表达于细胞膜。转移组移植瘤光密度值高于非转移组(0.4497±0.0705 vs 0.0435±0.0082,t=4.388,P=0.001)。结论 本研究成功构建稳定性好、移率高的鼻咽癌裸鼠移植瘤转移模型,且ELAM-1在裸鼠移植瘤中高表达,可促进鼻咽癌裸鼠移植瘤生长和转移。  相似文献   
70.
安冬  梁永林  李璐  毛慧芳  吴玉泓 《新中医》2021,53(6):192-194
溃疡性结肠炎(Ulcerative colitis,UC)是一种病情反复、迁延难愈的炎症肠病,已被世界卫生组织列为现代难治病之一[1]。本病病因及发病机制尚不明确,西药治疗效果欠佳。近年来中医药的介入,临床取得显著疗效。西医学认为疾病是机体在一定致病因素的作用下自稳调节紊乱,经过机体内损伤和抗损伤反应的相互斗争,表现出的一系列功能。  相似文献   
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