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71.
抗痫灵的电化学行为及吸附伏安法研究 总被引:2,自引:0,他引:2
抗痫灵在0.20 mol/L H2SO4底液、富集电位-0.70 V(vs Ag/AgCl)、扫速100 mV/s等条件下,用吸附伏安法得一灵敏的还原峰,峰电位-0.94 V,峰电流与抗痫灵浓度在3.0×10-9~1.0×10-8mol/L(富集时间tac=120 s),1.0×10-8~7.0×10-8mol/L(tac=90 s),7.0×10-8~7.0×10-7mol/L(tac=60 s),7.0×10-7~3.0×10-6mol/L(tac=45 s)范围内成线性关系,检测限可达1.0×10-9mol/L,并用于片剂及病人尿样的测定,得到满意的结果。以多种电化学手段研究抗痫灵的电化学行为及反应机理。实验表明属不可逆吸附波。测得扩散系数D为7.7×10-6cm2/s,电极反应速率常数k1为1.5×10-3cm/s,电极反应电子数n为2,电子转移系数α=0.52。抗痫灵的还原基团为分子中碳碳双键。 相似文献
72.
毛囊混合细胞在胶原/壳聚糖多孔支架上重建毛囊样结构 总被引:3,自引:0,他引:3
目的探讨利用毛囊混合细胞植入胶原/壳聚糖多孔支架内体外重建毛囊的可行性。方法用滴加法或注射法将体外培养的C57BL/6J近交系乳鼠背部皮肤毛囊混合细胞以不同传代数、不同细胞密度接种至胶原/壳聚糖多孔支架,倒置显微镜下观察支架表面或浅层的细胞生长或毛囊形成情况。将支架经10%甲醛固定后行组织学观察(H-E染色)。另用共聚焦激光扫描显微镜观察支架内活细胞的生长以及毛囊样结构的形成。结果在一定传代次数和细胞密度下,在支架内可形成具有毛干的毛囊样结构。激光共聚焦扫描显微镜发现团块内细胞排列呈同心圆状,整个三维结构似一长颈花瓶,且该结构仅见于注射法接种细胞的支架内。结论毛囊混合细胞植入胶原/壳聚糖多孔支架内体外可形成具有毛干的毛囊样结构。 相似文献
73.
Steven Appleby MD Kent Mcallister RT Morton J. Kern MD 《Catheterization and cardiovascular interventions》2008,71(6):800-802
After inserting a catheter into a vessel, guidewire exchange technique must be used to maintain vascular access. If the lumen of the catheter is blocked and the guidewire exchange cannot be used, the catheter can only be removed, vascular access is lost, and an alternate vascular approach attempted. We describe a technique to remove the blocked catheter and still maintain vascular access. © 2008 Wiley‐Liss, Inc. 相似文献
74.
主动固定电极在右室流出道间隔部起搏中的应用研究 总被引:14,自引:1,他引:14
目的评价主动固定电极在右室流出道间隔部起搏应用中的可行性和稳定性。方法160例起搏适应证患者随机分为两组,每组80例,一组采用主动固定电极行右室流出道间隔部起搏(简称主动固定电极组),另一组应用被动固定电极行右室心尖起搏(简称被动固定电极组),观察电极置入时间和心电图QRS波宽度,电极置入后随访观察起搏阈值、感知、阻抗,电极脱位及相关并发症。结果主动固定电极组的置入时间和X线曝光时间均长于被动固定电极(26.34±6.54minvs20.86±4.32min,16.78±5.38minvs8.67±4.52min;P均<0.01)。主动固定电极组电极置入15min时较置入即刻的起搏阈值明显下降(0.76±0.21mVvs1.12±0.25mV,P<0.01)。主动固定电极组起搏的QRS波时限较被动固定电极组短(0.14±0.04msvs0.16±0.03ms,P<0.01)。术后随访1,3,6个月,两组的起搏阈值、感知、阻抗均无差异,未见电极脱位等并发症。结论主动固定电极在右室流出道间隔部起搏中的应用是可行和稳定的。 相似文献
75.
Li Jia Xue Zhixin Wu Zhenbiao Bi Liqi Liu Huaxiang Wu Lijun Liu Shengyun Huang Xiangyang Wang Yong Zhang Yan Qi Wufang He Lan Dai Lie Sun Lingyun Li Xiaomei Shuai Zongwen Zhao Yi Wang Yanyan Xu Jian Zhang Hao Yu Hao Chen Xiaoxiang Bao Chunde 《Clinical rheumatology》2022,41(10):3005-3016
Clinical Rheumatology - To assess the clinical equivalence of TQ-Z2301, a biosimilar of adalimumab, to the reference adalimumab in the treatment of Chinese patients with active ankylosing... 相似文献
76.
Desmond R. H. Mao Marcus E. H. Ong Chungli Bang Mohamed D. T. Salim Yih Yng Ng Desiree A. Lie 《Prehospital emergency care》2018,22(2):260-265
Objectives: Paramedics' decision to terminate field resuscitation without a physician present may depend on personal and external factors. This study investigates factors associated with paramedic psychological comfort with termination of resuscitation (TOR) to inform future training. Methods: We administered an anonymous survey to all practicing paramedics in a large urban Asian Emergency Medical Services system where formal TOR training had not yet been conducted and field TOR was not routinely applied. The survey assessed psychological comfort using the validated Psychological Comfort Total (PCT) scale (summed score of 28 items, with higher scores representing greater comfort). We examined scores associated with four personal (prior resolution of personal loss, knowledge of survival probability, religious affiliation and experience with death pronouncements) and two external (location of patient and perceived trust of family) factors. Data were entered into Excel and analyzed by t-tests and ANOVA. Results: Response rate was 73.6% (254/345). Respondents were 30.3 years (mean, SD 7.1) with 7.2 years (mean, SD 5.54) of practice experience. Over 60% had been involved in 6 or more field death pronouncements in the prior 12 months. Higher PCT scores were associated with prior resolution of personal loss and knowledge of survival probability. Lower PCT scores were associated with patient location in a public place and perceived family lack of trust. PCT scores were not associated with paramedic religious affiliation or number of prior death pronouncements. Conclusions: Paramedic psychological comfort with field death pronouncement is associated with personal and external factors. Since paramedic comfort is important for protocol adoption, TOR education should target not only knowledge, but also public arena management, communication skills for engaging with families, and help paramedics resolve prior personal loss. 相似文献
77.
T Omland V V Bonarjee D W Nilsen J A Sundsfjord R T Lie G Thibault K Dickstein 《Heart (British Cardiac Society)》1993,70(5):409-414
OBJECTIVE--To evaluate the prognostic significance of plasma N-terminal pro-atrial natriuretic factor (1-98) concentrations measured in the subacute phase after acute myocardial infarction, and to compare the predictive value of measurement of N-terminal pro-atrial natriuretic factor (1-98) with the measurement of atrial natriuretic factor (99-126) and with clinical assessment of the degree of heart failure. DESIGN--Prospective observational. SETTING--Norwegian central hospital. PATIENTS--139 patients (mean (SD) age 66.9 (11.1) years, 71.2% males) with acute myocardial infarction. Patients in cardiogenic shock or with severe heart failure (New York Heart Association class IV) were excluded. MAIN OUTCOME MEASURE--Cardiovascular death within 12 months. RESULTS--During the follow up period 15 patients died. In a univariate Cox proportional hazards model N-terminal pro-atrial natriuretic factor (1-98) was significantly related to mortality (p = 0.0003). In a multivariate model the prognostic value of N-terminal pro-atrial natriuretic factor (1-98) was better than that of atrial natriuretic factor (99-126) and clinical assessment of heart failure (N-terminal pro-atrial natriuretic factor (1-98), p = 0.0003; atrial natriuretic factor (99-126), p = 0.4513; heart failure, p = 0.0719). The odds ratio estimate of patients in whom plasma concentrations of N-terminal pro-atrial natriuretic factor (1-98) were greater than 2000 pmol/l was 25 (95% confidence interval 2.8-225.0) compared with patients with plasma concentrations less than 1000 pmol/l. CONCLUSIONS--These results suggest that determination of plasma N-terminal pro-atrial natriuretic factor (1-98) in the subacute phase of myocardial infarction may provide clinically relevant prognostic information that is superior to that obtained from atrial natriuretic factor (99-126) measurements and clinical evaluation. 相似文献
78.
Modification of ventricular fibrillation latency following coronary artery occlusion in the conscious pig. 总被引:2,自引:0,他引:2
Abrupt occlusion of the left anterior descending coronary artery was performed on 45 unanesthetized farm pigs in order to evaluate the relative effects on the latency to ventricular fibrillation (VFL) of 1) adaptation of the animals to the laboratory, and 2) beta-receptor blockade by propranolol. Compared to control values, VFL was greatly lengthened (i.e., VF delayed or prevented) by adaptation (P smaller than 0.01), was shortened by large (2 MG/KG) doses of racemic propranolol in unadapted animals (P smaller than 0.02), and was again increased while under the influence of the drug, by adaptation (P smaller than 0.051). Neither a lower (0.02 mg/kg) dose of racemic propranolol, 2 mg/kg of dextropropranolol, nor ventricular pacing to a higher heart rate had an effect on VFL. The results suggest that reduced psychological stress was very effective in retarding or preventing the onset of VF, that low doses of propranolol were ineffective, and that higher doses were deleterious in unadapted animals. 相似文献
79.
80.
J T Lie 《Angiology》1989,40(8):764-767
The CREST syndrome (calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, telangiectasia) is a variant but not a benign form of scleroderma. Pulmonary hypertension without pulmonary fibrosis appears to be more prevalent in the CREST than in scleroderma patients. Moreover, pulmonary hypertension in CREST may be rapidly progressive and a cause of sudden death from severe cor pulmonale. 相似文献