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191.
192.
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
193.
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
194.
Xiuling Zhang Qing-Yu Zhang Dazhi Liu Ting Su Yan Weng Guoyu Ling Ying Chen Jun Gu Boris Schilling Xinxin Ding 《Drug metabolism and disposition》2005,33(10):1423-1428
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
195.
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
196.
Combination antibody therapy with epratuzumab and rituximab in relapsed or refractory non-Hodgkin's lymphoma. 总被引:5,自引:0,他引:5
John P Leonard Morton Coleman Jamie Ketas Michelle Ashe Jennifer M Fiore Richard R Furman Ruben Niesvizky Tsiporah Shore Amy Chadburn Heather Horne Jacqueline Kovacs Cliff L Ding William A Wegener Ivan D Horak David M Goldenberg 《Journal of clinical oncology》2005,23(22):5044-5051
PURPOSE: To explore the safety and therapeutic activity of combination anti-B-cell monoclonal antibody therapy in non-Hodgkin's lymphoma (NHL). PATIENTS AND METHODS: Twenty-three patients with recurrent B-cell lymphoma received anti-CD22 epratuzumab 360 mg/m(2) and anti-CD20 rituximab 375 mg/m(2) monoclonal antibodies weekly for four doses each. Sixteen patients had indolent histologies (15 with follicular lymphoma) and seven had aggressive NHL (all diffuse large B-cell lymphoma [DLBCL]). Indolent patients had received a median of one (range, one to six) prior treatment, with 31% refractory to their last therapy and 81% with high-risk Follicular Lymphoma International Prognostic Index scores. Patients with DLBCL had a median of three (range, one to eight) prior regimens (14% resistant to last treatment) and 71% had high intermediate-risk or high-risk International Prognostic Index scores. All patients were rituximab na?ve. RESULTS: Treatment was well tolerated, with toxicities principally infusion-related and predominantly grade 1 or 2. Ten (67%) patients with follicular NHL achieved an objective response (OR), including nine of 15 (60%) with complete responses (CRs and unconfirmed CRs). Four of six assessable patients (67%) with DLBCL achieved an OR, including three (50%) CRs. Median time to progression for all indolent NHL patients was 17.8 months. CONCLUSION: The full-dose combination of epratuzumab with rituximab was well tolerated and had significant clinical activity in NHL, suggesting that this combination should be tested in comparison with single-agent treatment. 相似文献
197.
胰岛素脂质体的制备及在电致孔下的经皮渗透 总被引:2,自引:0,他引:2
采用反相蒸发法制备了平均粒径122.7nm的胰岛素脂质体,并考察了电致孔经皮转运情况.结果表明,在电致孔条件下,胰岛素脂质体2h累积渗透量是载药脂质体被动扩散的1倍;是原药及其与空白脂质体混合物的2~3倍. 相似文献
198.
目的构建人凋亡诱导因子(AIF)基因功能片段的真核表达载体pcDNA3.1( )AIF,并初步研究AIF在细胞凋亡中的作用。方法从人细胞中提取总RNA,RTPCR扩增AIF基因片段;克隆到pMD18T载体上,通过酶切和测序进行鉴定;将AIF基因片段插入pcDNA3.1( ),构建真核表达载体;电转化淋巴母细胞Raji细胞,观察AIF的表达水平和功能。结果成熟AIF蛋白分子在真核细胞中表达,并转移到细胞核中,诱导Caspase非依赖性细胞凋亡。结论成功构建了pcDNA3.1( )AIF真核表达载体,AIF在Caspase非依赖性细胞凋亡中发挥重要作用。 相似文献
199.
目的:建立注射用熊胆粉及其原料熊胆粉指纹图谱的分析方法.方法:采用反相高效液相色谱法(RP-HPLC法).色谱柱用Shim-pack VP C18柱(4.0 mm×150 mm,5μm);流动相为甲醇-0.03 mol/L磷酸二氢钠溶液,梯度洗脱;检测波长为210 nm.结果:样品中各成分可得到较好的分离,指纹性较好;方法学考察表明,RP-HPLC法具有较好的重现性;指纹图谱相似度评价相关系数均大于0.9.结论:该指纹图谱可作为熊胆粉、注射用熊胆粉具有专属性的指纹图谱,适于作熊胆粉及其制剂的质量控制方法. 相似文献
200.
人血浆中罗红霉素的HPLC-MS测定及生物等效性研究 总被引:8,自引:1,他引:8
目的建立人血浆中罗红霉素的HPLC-MS测定方法,研究罗红霉素胶囊的生物等效性.方法采用双交叉实验设计,血样用乙腈沉淀后直接测定,根据血药浓度-时间数据计算药动学参数,估算相对生物利用度,采用双单侧t检验判断其生物等效性.结果两种罗红霉素制剂的t1/2分别为(13.18±2.01)h和(13.31±2.45)h,tmax分别为(1.8±1.2)h和(2.2±1.1)h,cmax分别为(6.14±1.76)μg·mL-1和(6.47±2.42)μg·mL-1,AUC0~72h分别为(71.81±28.40)μg·h·mL-1和(73.12±31.77)μg·h·mL-1,受试制剂的相对生物利用度为(100.6±11.4)%.结论本实验建立的方法灵敏、准确、简便,统计学结果表明两种制剂生物等效. 相似文献