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11.
目的观察并比较枸橼酸咖啡因及氨茶碱对早产儿不同时相血糖的影响程度。方法选择新生儿监护室诊断为原发性呼吸暂停的出生胎龄<34周的早产儿172例,采用随机数字表法分为咖啡因组与氨茶碱组各86例。比较两组早产儿用药前及用药后15、30min、1、1.5、2、4、6、12、12.5、24.5、36.5和48h血糖的变化。结果两组早产儿用药后除6、12和48h血糖值比较差异均无统计学意义(均P>0.05),其他用药后时相比较差异均有统计学意义(均P<0.05)。咖啡因组早产儿用药后30min血糖值上升,至1h达峰值,后逐渐回落;用药后30min、1、1.5、2及24.5h血糖值与用药前比较差异均有统计学意义(均P<0.05)。氨茶碱组早产儿用药后血糖值上升,30min达峰值,后逐渐回落;用药后15、30min、1、1.5、2、4、6、12.5、24.5、36.5h血糖值与用药前比较差异均有统计学意义(均P<0.05)。结论枸橼酸咖啡因可引起早产儿血糖升高,但升高幅度较氨茶碱小、持续时间也较短。 相似文献
12.
目的 分析2007-2017年浙江省24 388例罕见病住院病例特征,为制定罕见病防控策略提供依据。方法 收集2007-2017年浙江省10家三级甲等(三甲)医院罕见病住院病例资料和各年度住院数,进行描述性统计分析。结果 罕见病病例共24 388例,占住院总例数的2.69‰(24 388/9 054 201),病例数居前3位的疾病类型依次为"血液和造血器官疾病以及某些涉及免疫机能的异常"(占32.81%,8 001/24 388)、"先天性畸形、变形和染色体异常"(占24.87%,6 065/24 388)和"神经系统疾病"(占19.01%,4 635/24 388);2007-2017年罕见病病例数呈逐年增长趋势,年均增幅19.69%,而罕见病例数占同期住院总例数比例仅在2016-2017年明显上升,各类型罕见病时间分布呈不同特征;罕见病的病例数男女性别比为1.35:1(13 990/10 398),男女性别比最高的3类疾病依次为"消化系统疾病"(4.45:1,1 180/265)、"损伤、中毒和外因的某些其他后果"(3.51:1,281/80)和"神经系统疾病"(2.26:1,3 213/1 422);各年龄段罕见病类型、各类型罕见病年龄分布均呈不同特征;病例数居前10位的疾病占全部罕见病例数的53.55%(13 060/24 388),其中前3位疾病分别为成人粒细胞缺乏症(14.41%,3 515/24 388)、皮质基底核退化症(7.60%,1 854/24 388)和亨诺克-舍恩莱因紫癜(6.01%,1 466/24 388)。结论 本研究分析的浙江省2007-2017年24 388例罕见病住院病例的特征资料,是推动我国罕见病的研究、监测或登记数据库构建、制定防控策略的参考依据。 相似文献
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痤疮可辨为阴、阳两证。阳疮者,缘患者劳汗被寒、玄府闭合,汗脂凝聚日久不得外排,蕴热搏结气血而生疮化腐,疮症为热为痛,此为易治;阴疮者,由阳疮转化而来,缘患者外感寒风、内伤生冷,且医者又重用寒凉、失于托透,以至气血冰凝,久不溃脓或溃脓难出,此为难治。根据难治性痤疮临床表现,其多类属于阴疮,以阳虚表郁、邪闭毛窍为致病之关键,其中表郁毛窍、邪闭肌腠为病之标,阳虚阴凝为病之本。治疗当以温阳透发、祛邪外达为法。以麻黄附子细辛汤温阳化阴滞、发阳透毒治其本,待阴邪发越,即用火针强开门户、消疮排脓治其标。标本兼治、针药结合的方法治疗难治性痤疮在临床中能够安全有效地消除痤疮、改善皮损、降低复发率。 相似文献
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The objective of the present study was to evaluate the clinical, radiological, and functional outcomes of a subscapularis transthoracic surgical approach and a posterolateral surgical approach with debridement, bone graft fusion, and internal fixation for the treatment of upper thoracic tuberculosis.There is currently debate over the best surgical approach for the treatment of upper thoracic tuberculosis. Traditionally, the subscapularis transthoracic approach has been preferred; however, the posterolateral approach has gained popularity in the past few years.A prospective, consecutive cohort of 43 upper thoracic tuberculosis patients with a mean age of 39 years (range: 20–52 years) was followed up for a minimum of 12 months (range: 12–60 months). Patients were randomly divided into 2 groups. Group A (n = 21) was treated by the subscapularis transthoracic approach and group B (n = 22) was treated by the posterolateral approach. All cases were evaluated for clinical, radiological, and functional outcomes. Intraoperative blood loss, operative duration, intraoperative and postoperative complications, hospital stay, the cure rate, fusion time, and the Frankel scale were used for clinical and functional evaluation, whereas the kyphosis angle was used for radiological evaluation.Grafted bones were fused by 10 months in all cases. There was no statistically significant difference between groups before surgery in terms of gender, age, segmental tuberculosis, erythrocyte sedimentation rate (ESR), Frankel scale, or Cobb''s angle (P > 0.05). The average operative duration for Group B was lower than that of Group A. There were no significant differences in intraoperative blood loss, intraoperative and postoperative complications, hospital stay, grafted bone fusion time, or cure rate between groups (P > 0.05). The Cobb''s angle correction rate for group B (68.5%) was significantly better than that of group A (30.9%). The neurological score showed significant postoperative improvement in both groups, with no significant difference between the groups.The subscapularis transthoracic approach and the posterolateral approach with debridement, bone graft fusion, and internal fixation are both sufficient and satisfactory for the surgical treatment of upper thoracic tuberculosis. However, the posterolateral approach is superior to the subscapularis transthoracic approach in terms of surgical trauma, operative time, and kyphosis correction. 相似文献
19.
Learning to Discretize: Solving 1D Scalar Conservation Laws via Deep Reinforcement Learning 下载免费PDF全文
Yufei Wang Ziju Shen Zichao Long & Bin Dong 《Communications In Computational Physics》2020,28(5):2158-2179
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
20.
目的探讨补骨脂素抗增生性瘢痕的作用机制。方法体外培养成纤维细胞,按随机数字表法分为正常组(培养正常成纤维细胞)、瘢痕组(培养增生性瘢痕成纤维细胞)、TGF-β1组(10 ng/ml TGF-β1处理增生性瘢痕成纤维细胞5 min^12 h)、Smurf2 RNA干扰组[Smad泛素化调节因子2(Smad ubiquitin regulatory factor2,Smurf2)siRNA转染增生性瘢痕成纤维细胞72 h]、补骨脂素组(10μmol/L补骨脂素处理增生性瘢痕成纤维细胞继续培养72 h)、补骨脂素+TGF-β1组(增生性瘢痕成纤维细胞加入补骨脂素培养72 h后加入TGF-β1培养6 h)。采用Western blot法检测Smurf2、α-平滑肌肌动蛋白(α-actin SMA,α-SMA)蛋白表达;RT-PCR法检测Ⅰ型胶原蛋白mRNA表达;ELISA法检测TGF-β1蛋白分泌。结果与正常组比较,瘢痕组Smurf2蛋白[(0.83±0.08)比(0.38±0.07)]表达增加(P<0.05);与瘢痕组比较,Smurf2 RNA干扰组TGF-β1[(2.2±0.18)比(4.2±0.47)]表达降低(P<0.05);TGF-β1组Smurf2[(0.71±0.06)比(0.42±0.04)]、α-SMA[(1.42±0.12)比(0.91±0.09)]蛋白表达增加(P<0.05),Ⅰ型胶原蛋白mRNA[(0.72±0.09)比(0.41±0.07)]表达增加(P<0.05);补骨脂素组Smurf2[(0.05±0.01)比(0.42±0.04)]、α-SMA[(0.71±0.07)比(0.91±0.09)]蛋白表达降低(P<0.05),Ⅰ型胶原蛋白mRNA表达[(0.12±0.04)比(0.41±0.07)]降低(P<0.05)。结论补骨脂素可能通过TGF-β1/Smurf2信号通路抑制α-SMA蛋白表达,从而降低Ⅰ型胶原蛋白表达,起到抑制瘢痕形成的作用。 相似文献