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951.
An automated on-line method for simultaneous analysis of five phenothiazine drugs by high-performance liquid chromatography (HPLC)/sonic spray ionization mass spectrometry (SSI-MS) has been established, using backflush column switching. A 400-μl portion of serum sample diluted 81-fold with distilled water was subjected to the on-line system. In the system, an Oasis HLB cartridge was used as the precolumn for extraction; large molecules such as proteins in serum were discarded by use of distilled water containing 0.1% formic acid as a mobile phase. After switching a valve, the analytes trapped in the precolumn were eluted in the backflush mode and separated by a Chromolith Performance RP-18e column, which is composed of C18-bonded monolithic silica. The column effluents were then introduced into the SSI-MS. The present method provided successful separation and determination of six phenothiazines including an internal standard. Satisfactory linearities, reproducibility, and sensitivity were obtained at concentration levels that matched the toxic levels of phenothiazines. All drug peaks appeared within 18 min, and the system could be reequilibrated in only about 8 min for the next run. Because of the simplicity and rapidness of the method, it is likely to be useful in the fields of emergency medicine and forensic toxicology.  相似文献   
952.
目的:研究术前使用呼吸机无创正压通气治疗对脊柱侧凸患者围手术期肺功能的影响。方法:将40例Cobb角≥60°、肺功能存在中度以上限制性通气功能障碍、行脊柱侧凸矫形术的脊柱侧凸患者,随机分成A组和B组,每组20例。A组在术前采用BiPAP呼吸机,经用面罩无创正压通气(NIPPV)治疗1个月;B组常规术前准备。观察A组患者治疗前后肺功能的改善及两组患者围手术期肺功能的差异。结果:两组患者性别、年龄、身高、体重、Cobb角度、手术时间、手术径路、融合椎体数等基本情况比较无统计学差异(P>0.05);A组患者经NIPPV治疗后肺活量(VC)、肺活量占预计值的百分比(VC%)、用力肺活量(FVC)、第一秒最大呼气量(FEV1.0)、最大通气量(MVV)和最大通气量占预计值的百分比(MVV%)较治疗前明显改善(P<0.01);两组患者术中氧合指数、术后拔管时间、拔管后15min动脉血气PO2、PCO2比较有显著性差异(P<0.05)。结论:术前无创正压通气治疗可改善脊柱侧凸患者围手术期的肺功能,可缩短手术后气管插管的拔管时间,改善术后通气功能,有助于脊柱侧凸患者手术后早期恢复。  相似文献   
953.
954.
Stigma is a recognised problem for effective prevention, treatment, and care of HIV/AIDS. However, few studies have measured changes in the magnitude and character of stigma over time. This paper provides the first quantitative evaluation in Africa of the changing nature of stigma and the potential determinants of these changes. More specifically, it evaluates the dynamic relationship between stigma and (1) increased personal contact with people living with HIV/AIDS and (2) knowing people who died of AIDS. Panel survey data collected in Cape town 2003 and 2006 for 1074 young adults aged 14–22 years were used to evaluate changes in three distinct dimensions of stigma: behavioural intentions towards people living with HIV/AIDS; instrumental stigma; and symbolic stigma. Individual fixed effects regression models are used to evaluate factors that influence stigma over time. Each dimension of stigma increased in the population as a whole, and for all racial and gender sub-groups. Symbolic stigma increased the most, followed by instrumental stigma, while negative behavioural intentions showed a modest increase. Knowing someone who died of AIDS was significantly associated with an increase in instrumental stigma and symbolic stigma, while increased personal contact with people living with HIV/AIDS was not significantly associated with any changes in stigma. Despite interventions, such as public-sector provision of antiretroviral treatment (which some hoped would have reduced stigma), stigma increased among a sample highly targeted with HIV-prevention messages. These findings emphasise that changes in stigma are difficult to predict and thus important to monitor. They also indicate the imperative for renewed efforts to reduce stigma, perhaps through interventions to weaken the association between HIV/AIDS and death, to reduce fear of HIV/AIDS, and to recast HIV as a chronic manageable disease.  相似文献   
955.
建立了水产品中多组分生物胺的反相高效液相色谱-柱后衍生-荧光检测方法。采用荧光试剂邻苯二甲醛(OPA)为柱后衍生化试剂,在Capcell Pak MG-C18色谱柱上,通过梯度洗脱使酪胺、腐胺、尸胺、组胺、胍丁胺、精胺和亚精胺等7种生物胺得到良好分离,在给定的浓度范围内,各组分生物胺呈现良好线性相关(R^2〉0.999)。在水产品中添加生物胺混合标准溶液,平均回收率为88.3%~110.1%,相对标准偏差RSD小于10%。结合水产品的感官鉴定、pH值和TVBN值测定等方法检测水产食品的新鲜程度,分析了鱿鱼在不同保藏温度、保藏时间下的生物胺种类及含量的变化。其中胍丁胺和尸胺在鱿鱼的保藏过程中发生最显著变化,可以作为其质量变化的参考指标。  相似文献   
956.
目的:探讨单侧输尿管梗阻后大鼠肾间质纤维化发生过程中肝细胞生长因子(HGF)的表达及中药参附注射液对其的影响。方法:采用单侧输尿管结扎(UUO)制造梗阻性肾病模型,将56只大鼠随机分为对照组(假手术组)、手术组(UUO组)和治疗组(UUO+参附),术后7d、14d观察肾组织病理改变,应用免疫组织化学方法检测肾组织中HGF的表达。结果:与对照组相比,手术组肾间质出现了明显的纤维化,HGF的表达在术后第7天明显增加,第14天较第7天减弱,与手术组相比,治疗组肾间质纤维化明显减轻,而且HGF的表达在术后第7天明显上调,第14天较第7天上调更明显,有统计学差异(P〈0.05)。结论:参附注射液可以上调肾组织HGF的表达,减轻肾小管一间质纤维化,发挥肾保护作用。  相似文献   
957.
The present study was aimed to investigate the chemopreventive effects of Solanum trilobatum (ST) extract against diethylnitrosamine (DEN)-induced hepatocarcinogenesis promoted by Phenobarbital (PB) in Wistar rats. Hepatocarcinogenesis was initiated by a single intraperitoneal injection of DEN (200 mg/kg b.w.) and promoted with PB (0.05%) in basal diet. The experimental study extended for periods of 13 and 26 weeks. Alcoholic extract of ST was orally administered for the entire experimental period after initiation along with commencement of promotion. The chemopreventive effect of ST was assessed from the incidence of nodules, drug metabolizing phase I components such as contents of cytochrome P450, cytochrome b(5), activities of NADPH cytochrome c reductase, NADH - cytochrome b(5) reductase and phase II components such as levels of glutathione, activities of UDP-glucuronyl transferase, glutathione S-transferase and gamma-glutamyl transpeptidase in the liver. Lipid peroxidation at basal and prooxidants-induced (NADPH + ADP + Fe and Ascorbate + Fe) states was assessed in the microsomes. Animals administered with ST extract evidenced significant inhibition of tumor nodular incidence in DEN + PB + ST animals compared to DEN + PB animals, with favorable alterations in the hepatic drug-metabolizing phase I and phase II components. Administration of ST inhibited basal and pro-oxidant-induced lipid peroxidation. The present result suggests the probable mediation of chemoprevention by ST against DEN-induced carcinogenesis by the modulation of drug metabolizing components in the liver of treated animals.  相似文献   
958.
A new radioactivity solution standard of 210Pb has been developed and will be disseminated by the National Institute of Standards and Technology (NIST) as standard reference material (SRM) 4337. This new 210Pb solution standard is contained in a 5 mL flame-sealed borosilicate glass ampoule, consists of (5.133±0.002) g of a nominal 1 mol L−1 nitric acid solution, has a density of (1.028±0.002) g mL−1 at 20 °C, has carrier ion concentrations of about 11 μg Pb2+ and 21 μg Bi3+ per gram of solution, and is certified to contain a massic activity (9.037±0.22) kBq g−1 as of the reference time 1200 EST, 15 June 2006. All of the uncertainties cited above correspond to standard uncertainties multiplied by a coverage factor k=2. The standardization for the 210Pb content of the solution was based on 4πβ liquid scintillation (LS) measurements using CIEMAT/NIST 3H-standard efficiency tracing (CNET). Confirmatory determinations were also performed by high-resolution HPGe γ-ray spectrometry, by 2π spectrometry with a Si surface barrier detector of separated 210Po, and by 4πβ(LS)–γ(NaI) anticoincidence counting.  相似文献   
959.
Ultrashort echo time (UTE) imaging is a technique that can visualize tissues with sub-millisecond T(2) values that have little or no signal in conventional MRI techniques. The short-T(2) tissues, which include tendons, menisci, calcifications, and cortical bone, are often obscured by long-T(2) tissues. This paper introduces a new method of long-T(2) component suppression based on adiabatic inversion pulses that significantly improves the contrast of short-T(2) tissues. Narrow bandwidth inversion pulses are used to selectively invert only long-T(2) components. These components are then suppressed by combining images prepared with and without inversion pulses. Fat suppression can be incorporated by combining images with the pulses applied on the fat and water resonances. Scaling factors must be used in the combination to compensate for relaxation during the preparation pulses. The suppression is insensitive to RF inhomogeneities because it uses adiabatic inversion pulses. Simulations and phantom experiments demonstrate the adiabatic pulse contrast and how the scaling factors are chosen. In vivo 2D UTE images in the ankle and lower leg show excellent, robust long-T(2) suppression for visualization of cortical bone and tendons.  相似文献   
960.
We assessed the relations of visual hallucinations (VH) to cardiovascular autonomic dysfunction in patients with Parkinson's disease (PD). The subjects were 37 patients without VH (VH(-)) and 31 with VH (VH(+)). Autonomic function was evaluated on the basis of cardiac 123-radioiodinated metaiodobenzylguanidine (123I-MIBG) uptake and hemodynamic testing with Valsalva maneuver. Systolic blood pressure (SBP) and plasma norepinephrine concentrations (NE) were measured by tilt-table testing. 123I-MIBG uptake was lower in VH(+) than VH(-). Hemodynamic studies showed that VH(-) had only cardiac sympathetic and parasympathetic dysfunction, while VH(+) additionally had reduced vasomotor sympathetic functions. The fall in SBP during tilt-table testing was greater in VH(+) than VH(-). NE and its difference in the supine and upright positions were decreased in VH(+). We conclude that cardiac and vasomotor sympathetic dysfunction is more severe in VH(+) than in VH(-). Severe dysfunction in PD with VH is probably attributed to Lewy-body lesions or neuronal loss in sympathetic ganglia, the central autonomic system, or both.  相似文献   
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