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排序方式: 共有195条查询结果,搜索用时 15 毫秒
1.
目的研究和开发支持中医和现代生物医学本体和术语集的语义标注系统。方法以MedPortal本体库和中医临床术语集等为术语资源库,设计语义标注系统工作流程和功能框架,并开发Web应用系统。结果构建了一个基于Web的中医药文献语义标注系统,支持语料库管理与维护、术语词典管理、语义标注和语义检索等功能,既可以为基于机器学习的信息抽取算法研究提供训练集,又能实现语义层面的多来源数据集成与知识融合。结论该中医药文献语义标注系统设计方案已经过实际项目验证,可为其他同类系统研发提供参考。  相似文献   
2.
目的探讨促红素对大鼠重型颅脑损伤伴休克后继发性损伤的保护机制。方法采用改进Feeney法制作颅脑损伤模型,同时行股动脉放血造成休克模型,将70只雄性Wistar大鼠用随机数字表法分为干预组及对照组。双抗体夹心酶联免疫(ELISA)分析S-100β蛋白及IL-1β变化。结果大鼠重型脑损伤伴休克后,IL-1β呈高表达,S-100β表达也增高,二者存在正相关关系。促红素能够在一定程度上抑制IL-1β高表达。结论促红素可能通过抑制颅脑损伤后继发的过度炎症反应而减轻继发性脑损伤。  相似文献   
3.
紫菀是临床常用的化痰止咳要药,始载于《神农本草经》。紫菀化学成分丰富,主要包括萜类及其苷、肽类、黄酮、蒽醌、香豆素、有机酸、酚类、甾醇、挥发油及苯丙素类等。现代药理学研究表明,紫菀在抗肿瘤、抗病毒、抗氧化等方面也具有显著的药理活性。对紫菀的资源分布、化学成分、药理活性研究进展进行综述,并依据质量标志物的概念及确定原则对紫菀的质量标志物进行预测分析,以期为紫菀质量标准的深入研究提供参考。  相似文献   
4.
ObjectiveTo investigate the risk factors for, and outcomes of, preoperative asymptomatic pulmonary embolism (PE) in patients ≥60 years old following delayed operation for hip fracture.MethodsFrom March 2017 to December 2018, 90 patients aged ≥60 years with hip fracture who suffered a delay in surgery were recruited to this prospective study following admission to our hospital. Computed tomography pulmonary angiography (CTPA) was used to detect preoperative asymptomatic PE and calculated its incidence. Time from injury to admission, baseline characteristics, medical comorbidities, and blood biomarker levels were evaluated as potential risk factors. Logistic regression analysis was used to identify risk factors. Mortality and major bleeding events were recorded and compared between individuals with PE and without. Data were analyzed by t‐test, Mann–Whitney U test, χ 2 test, Fisher''s exact test, and logistic regression analysis.ResultsThe incidence of preoperative asymptomatic PE was 18.9% (17/90 patients). In the univariate analysis, the risk factors for preoperative asymptomatic PE were male sex, hypertension, cerebrovascular accident, smoking, plasma D‐dimer level, potassium level, urea level, creatinine level, and cysteine level. Multivariate logistic regression analysis showed that the risk of preoperative asymptomatic PE was higher in patients with hypertension (odds ratio [OR] = 10.048; 95% confidence interval [CI], 1.118–90.333), cerebrovascular accident (OR = 20.135; 95% CI, 1.875–216.164), smoking (OR = 48.741; 95% CI, 4.155–571.788), high plasma D‐dimer levels (OR = 1.200; 95% CI, 1.062–157.300), and high plasma potassium levels (OR = 12.928; 95% CI, 1.062–157.300). All patients were followed up for 21.0 months (range, 2 to 36 months). Mortality within the first year postoperatively was higher in patients with PE (29.41% vs 9.59%, P = 0.046).ConclusionsIn view of the high incidence of preoperative asymptomatic PE and the inferior prognosis in individuals with PE, routine CTPA examination for preoperative asymptomatic PE could be useful for patients aged ≥60 years with hip fracture for whom surgery is delayed.  相似文献   
5.
Sun Z  Yao K  Wu R  Shentu X  Xu W 《中华眼科杂志》1999,35(6):462-464
目的 研究碱性成纤维细胞生长因子(basic fibroblast growth factor,bFGF)、胰岛素样生长因子-1(insulin-like growth factor-1,IGF-1)及二者的共同作用对体外牛晶体上皮细胞(bovine lensepithelial cell,BLEC)增殖的影响。方法 BLEC原代培养,取第4例细胞种入24孔板,加入不同浓度的bFGF、IGF-1,  相似文献   
6.
393株念珠菌属的鉴定及药物敏感性分析   总被引:4,自引:2,他引:4  
目的了解本院患者念珠菌属感染的特点及药敏状况。方法采用法国科玛嘉念珠菌属显色培养基分离鉴定菌株,用K-B纸片扩散法进行药敏试验。结果3年间共分离393株念珠菌属,白色念珠菌检出率最高(63.10%),其次是热带念珠菌(12.47%)、光滑念珠菌(9.41%)、克柔念珠菌(8.40%)、新型隐球菌(1.53%)和其他念珠菌(5.09%);所有标本中,检出率排前5位的是痰液156株(39.69%)、大便66株(16.79%)、中段尿45株(11.45%)、白带38株(9.67%)、咽拭子34株(8.65%);在9种抗真菌药药敏试验中,5-氟胞嘧啶、氟康唑、克霉唑、两性霉素B、制霉菌素有较高的敏感性。结论念珠菌属在临床标本中分离率较高,不同菌种对不同药物敏感性存在较大差异,临床上应重视念珠菌属的培养、鉴定和药敏试验,合理选用抗真菌药物。  相似文献   
7.
AIM: To determine the association of gap junction protein alpha 3 (GJA3) gene tag single-nucleotide polymorphisms (SNPs) with susceptibility to age-related cataract (ARC). METHODS: In total, 486 ARC patients were matched with 500 healthy controls. All the participants underwent complete ophthalmic examinations. Haplotype-tagging SNPs of GJA3 gene were selected from the HapMap Beijing Han Chinese population. Genomic DNA was extracted from the peripheral blood leukocytes of all the subjects. Under three different genetic models: dominant, recessive, and additive, the association between SNPs and ARC was examined. After adjusting for age and sex, the genetic effects of the GJA3 SNPs were evaluated with logistic regression analysis. RESULTS: Four tag GJA3 SNPs (rs6490519, rs9506430, rs9509053, and rs9552089) were included in the present study. None of the SNPs showed a significant relationship with an altered risk of total ARC under the dominant, recessive, or additive models. In the subgroup analysis, rs9506430 had a significant effect on the formation of a posterior subcapsular cataract (P=0.002, OR: 0.227, 95%CI: 0.088-0.590) under the recessive model. CONCLUSION: Our study indicates that GJA3 variants may influence the development of posterior subcapsular cataracts. Further studies need to be designed to confirm this possibility.  相似文献   
8.
The emergence of carbapenem-resistant organisms posed considerable threat to global health while only limited treatment options are available and led to efforts to discover a novel way to treat them. To evaluate in vitro synergistic activity of meropenem plus ertapenem, a total of 203 carbapenem-resistant strains, collected from 12 provinces and municipalities in China, were examined with a dual carbapenem combination therapy. The statistical software R was used for analysis. Two hundred and one (201) of carbapenem-resistant strains mainly produced four types of carbapenemase: KPC-2 (n = 142, 69.95%), OXA-232 (n = 7, 3.45%), NDM (n = 38, 18.72%; 36 NDM-1, 1 NDM-4, 1 NDM-5), and IMP (n = 15, 7.39%; 1 IMP-26, 10 IMP-30, 4 IMP-4). Fifty-one out of two hundred and three (51/203 or 25.12%) of the examined strains showed a synergistic effect for the meropenem plus ertapenem combination throughout the checkerboard method, while only three isolates showed potential clinically relevant synergy (3/203, 1.48%). An additive effect was observed in 55/203 (27.09%) of the examined strains. Ninety-seven of the examined isolates (47.78%) showed fractional inhibitory concentration (FIC) greater or equal to 2 (indicating antagonism). The synergistic activity of meropenem plus ertapenem combination suggests this combination can be a possible way to treat the infection caused by the carbapenem-resistant organisms, especially for IMP or NDM producer with a lesser minimum inhibitory concentration (MIC) and the infected individual who was not recommended to use colistin or tigecycline.  相似文献   
9.
神经生长因子脂质体大鼠鼻腔给药的药效学研究   总被引:5,自引:0,他引:5       下载免费PDF全文
 目的对神经生长因子(nerve growth factor,NGF)和NGF脂质体(NGF-SSL)鼻腔给药的药效学进行研究,并与NGF静脉给药相比较。方法鹅膏蕈氨酸(ibotenicacid,IBO)大鼠Meynert核注射制造阿尔茨海默氏病(alzheimer'sdisease,AD)模型,以生理盐水Meynert核注射作为假手术对照组,通过水迷宫试验,跳台实验和乙酰胆碱酯酶(AchE)组织化学染色来评价AD模型。并应用此模型采用同样方法研究NGF静脉给药,NGF和NGF-SSL鼻腔给药后的药效。结果AD模型经鉴定能够应用于药效研究。NGF鼻腔给药药效优于NGF静脉注射,NGF经脂质体包载后药效进一步提高。NGF-SSL鼻腔给药后能明显保护胆碱能神经元免受损伤,动物游泳时间缩短,跳台潜伏期延长,AchE染色积分光密度接近正常大鼠。结论鼻腔给药能够实现药物给药途径上的脑靶向,药物经脂质体包载后能明显增加其脑摄入,提高药效。  相似文献   
10.
药物神经毒性非临床安全性评价是早期筛选神经毒性药物及降低药物研发风险的重要手段,而且能为后续的临床试验提供毒性证据支持.原国家食品药品监督管理总局(China Food and Drug Administration,CFDA)、经济合作与发展组织(Organization for Economic Co-operat...  相似文献   
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