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61.
Liang H  Ding M  Nakamura R  Bressler SL 《Neuroreport》2000,11(13):2875-2880
Anatomical studies of the visual cortex demonstrate the existence of feedforward, feedback and lateral pathways among multiple cortical areas. Yet relatively little evidence has previously been available to show the causal influences of these areas on one another during visual information processing. We simultaneously recorded event-related local field potentials (LFPs) from surface-to-depth bipolar electrodes at six sites in the ventral region of the right hemisphere visual cortex in a highly trained macaque monkey during performance of a visual pattern discrimination task. Applying a new statistical measure, the short-time directed transfer function (STDTF), to the LFP data set, we charted the changing strength and direction of causal influence between these cortical sites on a fraction-of-a-second time scale. We present results showing, for the first time, the dynamics of distinct feedforward, feedback and lateral influences in the ventral portion of the primate visual cortex during visual pattern processing.  相似文献   
62.
丁晓明  刘迅 《齐鲁药事》2005,24(11):698-699
患者女,42岁,于2005年4月10日,因尿频、尿急、尿痛2d就诊,查体T 37℃,BP16/9 Kpa,心率68·min-1,心肺未见异常,双下肢无水肿,双侧肾区无叩击痛,既往健康,无药物过敏史,未曾应用过左氧氟沙星。查血常规:WBC10×109L-1、N78%。尿常规,BLD()、GLU()、Pro(+)、WBC()。镜检,WBC 10×15个/HP。临床诊断为,急性泌尿系感染。医嘱给予抗生素治疗。静脉滴注0·9%生理盐水250ml+左氧氟沙星0·3g 30min后,患者感胸闷、伴有大汗、脉搏细弱。询问患者晨起后未进早餐,考虑为低血糖反应。医嘱减慢滴速,多饮水,20min后症状缓解。第二天重复上述药物…  相似文献   
63.
Despite recent progress in the identification and characterization of numerous nasal biotransformation enzymes in laboratory animals, the expression of biotransformation genes in human nasal mucosa remains difficult to study. Given the potential role of nasal biotransformation enzymes in the metabolism of airborne chemicals, including fragrance compounds and therapeutic agents, as well as the potential interspecies differences between laboratory animals and humans, it would be highly desirable to identify those biotransformation genes that are expressed in human nasal mucosa. In this study, a global gene expression analysis was performed to compare biotransformation enzymes expressed in human fetal and adult nasal mucosa to those expressed in liver. The identities of a list of biotransformation genes with apparently nasal mucosa-selective expression were subsequently confirmed by RNA-polymerase chain reaction (PCR) and DNA sequencing of the PCR products. Further quantitative RNA-PCR experiments indicated that, in the fetus, aldehyde dehydrogenase 6 (ALDH6), CYP1B1, CYP2F1, CYP4B1, and UDP glucuronosyltransferase 2A1 are expressed preferentially in the nasal mucosa and that ALDH7, flavin-containing monooxygenase 1, and glutathione S-transferase P1 are at least as abundant in the nasal mucosa as in the liver. The nasal mucosal expression of CYP2E1 was also detected. These findings provide a basis for further explorations of the metabolic capacity of the human nasal mucosa for xenobiotic compounds.  相似文献   
64.
中医医院急诊工作的建议   总被引:1,自引:0,他引:1  
中医医院急诊工作不仅关系着中医医院综合服务功能的完善,而且也是医院可持续发展的标志之一.笔者认为,中医医院急诊工作必须注重以下几个方面.  相似文献   
65.
目的 构建轻型缺血性脑卒中(MIS)患者2年内复发的随机森林和决策树预测模型,并分析模型的临床应用价值。方法 回顾性收集2020年7月1日至12月31日于山西省心血管病医院神经内科就诊的520例MIS患者的病历资料,根据2年内是否复发将患者分为复发组和未复发组。基于缺失森林对数据进行填补,根据文献检索与专家讨论结果筛选预测变量并进行单因素分析,合成少数过采样技术-标称连续(SMOTE-NC)技术处理数据不平衡,采用贝叶斯优化十折交叉验证构建随机森林、决策树模型并与Logistic回归模型进行比较。基于受试者工作特征曲线下面积(AUC)、布里尔分数(BS)与校准曲线分别评价模型的区分度与校准度。对预测性能最好的模型采用SHAP模型解释预测结果。结果 2年内复发患者共93例(17.9%)。两组患者的年龄,吸烟、糖尿病、循环梗死部位、多发性脑梗死比例,以及舒张压、红细胞压积、血小板计数、低密度脂蛋白水平比较,差异有统计学意义(P<0.05)。Logistic回归模型、决策树模型与随机森林模型在测试集中,预测MIS患者2年内复发情况的AUC(95%CI)分别为0.764(0.691~0....  相似文献   
66.
目的 从GSK-3β/β-catenin角度探讨炎症反应对糖尿病SD大鼠慢性创面修复的影响。方法 使用高脂饲料喂养联合腹腔注射链脲霉素(Streptozocin,STZ)及手术制备全层皮肤缺损的方法建立糖尿病SD大鼠创面模型,成模后随机分为模型组(n=15),磺胺嘧啶银组(n=15)及解毒生肌膏组(n=15),并设立正常创面组(n=15)。磺胺嘧啶银组创面和解毒生肌膏组创面予以磺胺嘧啶银软膏和解毒生肌膏外敷,每日1次,模型组与正常创面组不予干预。给药后第3天、7天和14天肉眼观察各组大鼠的创面愈合情况,计算创面愈合率;HE观察组织基本形态;Masson检测胶原生成情况;超微电镜观察内质网结构差异;免疫组织化学法检测肿瘤坏死因子-α(Tumor necrosis factor-α,TNF-α)和白细胞介素-6(Interleukin-6,IL-6)表达;蛋白质免疫印迹法检测糖原合成酶激酶-3β(glycogen synthase kinase-3β,GSK-3β)蛋白和β-连环蛋白(β-catenin)蛋白表达。结果 给药后3天解毒生肌膏组创面愈合率高于模型组(P<0.05);给药后14天解毒生肌膏组创面愈合率高于磺胺嘧啶银组(P<0.05)。HE结果 给药后3、7天解毒生肌膏组创面较其他组肿胀程度较小,毛细血管数量丰富;14天,解毒生肌膏组和正常创面组出现皮肤附属器新生,组织结构完整度好。Masson结果 解毒生肌膏组较其他各组胶原纤维分布均匀,排列结构较为整齐,新生胶原纤维更为粗壮,分布均匀,排列整齐。电镜结果:解毒生肌膏组内质网丰富,数量较多,形态结构趋于正常。免疫组织化学法结果:与模型组相比,各组TNF-α、IL-6表达水平明显降低;解毒生肌膏组TNF-α表达水平低于正常创面组;解毒生肌膏组TNF-α、IL-6表达低于磺胺嘧啶银组。Western blot法结果显示:与正常创面组相比,各组β-catenin表达量均上调(P<0.05),解毒生肌膏组上调表达量最少;与正常创面组相比,各组GSK-3β蛋白表达含量明显下调(P<0.05);给药后7天,磺胺嘧啶银组和解毒生肌膏组GSK-3β蛋白表达含量上调(P<0.05),但仍低于正常创面组。结论 解毒生肌膏作用糖尿病大鼠创面修复机制通过调控GSK-3β和β-catenin表达,使炎症因子IL-6和TNF-α表达下调,最终达到糖尿病大鼠慢性创面愈合。  相似文献   
67.
Background:The diagnosis and treatment rate of Parkinson disease (PD) with depression has a low diagnostic rate, and there is no consensus on the choice of treatment mode. This study evaluates the global research trends of scientific outputs related to depression in PD from multiple perspectives, using a bibliometric analysis and visualization tool to scientifically analyze the knowledge from the literature.Methods:Literature related to depression in PD published from 2012 to 2021 was included and selected from the Web of Science Core Collection database in October 2021. CiteSpace software was used to visualize and analyze co-occurrence analyses for countries, institutions, authors, and keywords.Results:A total of 4533 articles from the Web of Science database were included. The United States made the largest contribution with the majority of publications (1215; 29.40%). Toronto University was the most productive institution. PD, depression, quality of life, dementia, nonmotor symptom, prevalence, anxiety, Alzheimer disease, symptom, and disorder would be significantly correlated with depression in PD. The current hot spots in this field focus on the following: risk factors for depression in PD, assessment scale of depression in PD, and rehabilitation of depression in PD.Conclusions:This analysis not only reveals the current research trends and hotspots but also provides some instructive suggestions on the development of depression in PD.  相似文献   
68.
Five previously undescribed epoxy octa-hydronaphthalene polyketides, altereporenes A–E (1–5) were isolated from rice culture of the endophytic fungus Alternaria sp. YUD20002 derived from the tubers of Solanum tuberosum. Their structures were determined on the basis of comprehensive spectroscopic analyses, while the absolute configurations were elucidated by the comparison of experimental and calculated specific rotations. Meanwhile, the antimicrobial, cytotoxic, anti-inflammatory and acetylcholinesterase inhibitory activities of compounds 1–5 were also investigated.

Five previously undescribed epoxy octa-hydronaphthalene polyketides, altereporenes A–E (1–5) were isolated from rice culture of the endophytic fungus Alternaria sp. YUD20002 derived from the tubers of Solanum tuberosum.  相似文献   
69.
There is a lack of studies on the association between whole grain intake and cardiometabolic risk factors in China and the current definition of whole grains is inconsistent. This study defined whole grains in two ways, Western versus traditional, and examined their associations with the risks of major cardiometabolic factors (CMFs) among 4706 Chinese adults aged ≥18 years, who participated in surveys both in 2011 and in 2015. Diet data were collected by consecutive 3 d 24 h recalls, together with household seasoning weighing. Whole grains were defined as grains with a ratio of fiber to carbohydrate of ≥0.1, while coarse grains were defined as grains except for rice and its products, and wheat and its products. Multivariable logistic regressions were modeled to analyze the associations of intakes of whole grains and coarse grains, respectively, with risks of major CMFs including obesity-, blood pressure-, blood glucose- and lipid-related factors, which were defined by International Diabetes Federation and AHA/NHLBI criteria. After adjusting for potential confounders, the odds of elevated LDL-C decreased with the increasing intake levels of whole grains (OR 0.64, 95% CI 0.46–0.88, p-trend < 0.05). Moreover, adults with the whole grain intake of 50.00 to 150.00 g/day had 27% lower odds of overweight and obesity (OR 0.73, 95% CI 0.54–0.99) and 31% lower odds of elevated LDL-C (OR 0.69, 95% CI 0.49–0.96), as compared with non-consumers. In conclusion, given the significant nutrient profiles of whole grains and coarse grains, the adults with higher intakes of whole grains only may have a lower risk of LDL-C and overweight and obesity.  相似文献   
70.
Porcine epidemic diarrhea (PED), characterized by diarrhea, vomiting, and dehydration, is an acute enteric infectious disease of pigs. The disease is caused by porcine epidemic diarrhea virus (PEDV), which infects the intestinal mucosal surface. Therefore, mucosal immunization through the oral route is an effective method of immunization. Lactic acid bacteria, which are acid resistant and bile-salt resistant and improve mucosal immunity, are ideal carriers for oral vaccines. The S1 glycoprotein of PEDV mediates binding of the virus with cell receptors and induces neutralizing antibodies against the virus. Therefore, we reversely screened the recombinant strain pPG-SD-S1/Δupp ATCC 393 expressing PEDV S1 glycoprotein by Lactobacillus casei deficient in upp genotype (Δupp ATCC 393). Mice were orally immunized three times with the recombinant bacteria that had been identified for expression, and the changes of anti-PEDV IgG and secreted immunoglobulin A levels were observed over 70 days. The results indicated that the antibody levels notably increased after oral administration of recombinant bacteria. The detection of extracellular cytokines on the 42nd day after immunization indicated high levels of humoral and cellular immune responses in mice. The above results demonstrate that pPG-SD-S1/Δupp ATCC 393 has great potential as an oral vaccine against PEDV.  相似文献   
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