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81.
The application of a circular dichroism (c.d.) detection system in HPLC using a chiral stationary phase is presented. The simultaneous measurement of the absorbance and c.d. signal allows the evaluation of the anisotropy factor (g = Δ/) and thus the determination of the enantiomeric excess (e.e.) of the eluates. When this detection system is used in preparative chiral chromatography the collection of the enantiomeric fractions can be readily optimized.  相似文献   
82.
本文对81例乙型肝炎病人的肝活检组织进行了电镜观察,发现HBsAg的阳性率达93.8%。电镜下,HBsAg细丝不仅有一般的管状细丝型,还有分枝管型和管泡型,而且CAH病人肝组织不易找到HBsAg丝(易见者仅9%),CPH,CLH则多数(79.5%)为易见及可见,二者有高度显著性差异(P<0.01)。  相似文献   
83.
The study described tested the hypothesis that increasing amounts of dietary fibre (DF) in the diet of patients on haemodialysis (HD) may achieve positive clinical benefit without adversely affecting serum potassium and plasma phosphate. The current diet of 20 home HD patients was supplemented with 15g unprocessed wheat bran incorporated into three 'bran muffins' eaten daily for a trial period of 28 days. During this period patients reported an improvement in bowel habit. Serum potassium decreased slightly but not significantly ( P =0.242) but there was a significant rise in plasma phosphate ( P =0.004). These findings suggest that when increasing DF in devising HD dietary regimes, plasma phosphate is possibly the more sensitive biochemical variable following introduction of wheat bran.  相似文献   
84.
三尖杉酯碱诱导慢性髓系白血病K-562细胞凋亡的实验研究   总被引:4,自引:0,他引:4  
目的阐明三尖杉酯碱(HT)作用于K562细胞的机制。方法应用细胞形态、DNA凝胶电泳和流式细胞仪等检测,观察HT对K562细胞株的作用方式,进一步用RT-PCR方法研究bcr/abl基因在转录水平的改变。结果0.01~100.00μg/ml浓度HT可诱导K562细胞凋亡,并呈时间和剂量依赖性。随着药物作用时间的延长,bcr/abl基因的转录下调。结论低浓度HT就可通过抑制bcr/abl基因的表达,诱导K562细胞凋亡。  相似文献   
85.
SUMMARY: In patients with chronic renal failure (CRF), hyperleptinaemia has been widely reported, but the exact mechanisms leading to elevated leptin levels are unclear. Impaired renal clearance of leptin and the influence of other hormones may be important. In this study, we measured serum leptin levels in 150 patients on haemodialysis, peritoneal dialysis or in the predialysis phase of CRF. Furthermore, we measured plasma levels of insulin, growth hormone (GH) and insulin-like growth factor 1 (IGF-1), as well as plasma levels of triacylglycerols and total low density lipoprotein (LDL)- and high density lipoprotein (HDL)-cholesterol. We observed significantly elevated levels of leptin, particularly in female patients, and leptin was shown to correlate significantly with insulin, total and LDL-cholesterol and log triacylglycerols. Leptin was inversely correlated with GH concentrations, but was not correlated with IGF-1 levels. Despite the multiple correlations established between leptin levels and other variables, only hyperinsulinaemia in CRF seems to be important as a determinator of leptin levels.  相似文献   
86.
目的观察中西医结合治疗慢性鼻窦炎的疗效.方法:对76例慢性鼻窦炎病人采用阿奇霉素,每次1粒(0.25g),替硝唑片每次1g口服,二者均一日1次,首剂量加倍,中成药藿胆丸每次服6克,一日两次,7天为一疗程,服药最长者2周。结果:显效56例(占73.7%),有效18例(占23.7%),无效2例(占2.6%),总有效率97.4%。结论:中西医结合治疗慢性鼻窦炎具有良好疗效。  相似文献   
87.
88.
Collagenous colitis is characterized by the presence of a thick subepithelial collagen band in the colonic mucosa. The condition was diagnosed on rectal biopsy in 10 patients (one male, nine females) who presented with watery diarrhoea. Although rectal mucosal erythema was present in three and ulceration in two, the mucosa was of normal endoscopic appearance in five of the patients. There was marked variability in the thickness of the submucosal collagen band, both between and within individuals. Empirical drug therapy included sulphasalazine, glucocorticoids and antidiarrhoeals. All patients reported symptomatic improvement.  相似文献   
89.
Open, Double-Blind and Long-Term Study of Vigabatrin in Chronic Epilepsy   总被引:5,自引:4,他引:1  
We performed an open, double-blind, and long-term study of vigabatrin (gamma-vinyl-GABA, GVG) in patients with treatment-resistant epilepsy who were receiving only one or at most two standard antiepileptic drugs (AEDs). The novel design included a parallel, double-blind, placebo-controlled phase that minimized the number of patients receiving placebo and allowed determination of the optimum dose of GVG for each patient before initiation of the double-blind phase. The study was divided into four phases. The first phase was a 6-week period of baseline observation. In the second phase, GVG was added openly to previous AEDs for 8 weeks. During the first 2 weeks of this phase, the dose of GVG was increased weekly and then, in the absence of adverse effects, was held constant for the next 6 weeks. At the end of this open phase, seizure frequency during the 6 weeks of constant treatment was compared with the baseline seizure frequency for each patient. Patients who experienced reduction greater than 50% in the frequency of any seizure type during the open phase were defined as responders. These responders were then entered into the third and double-blind phase, in which they were randomly allocated wither to continue active GVG treatment or placebo for 8 weeks. Thirty-three patients entered the study; 31 of 33 patients completed the initial open phase. Twenty patients achieved a reduction greater than or equal to 50% in the frequency of one or more seizure types and were eligible for the double-blind phase; 10 were randomized to continue GVG and 10 were randomized to placebo.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
90.
产科危重患者多器官功能障碍综合征的临床分析   总被引:4,自引:0,他引:4  
目的 :分析产科危重患者多器官功能障碍综合征 (MODS)的发病特点及诱因 ,以及与急性生理与慢性健康状况评分II(APACHEII)的关系。方法 :回顾分析 2 0 0 0年1月至 2 0 0 4年 4月转入GICU产科危重患者中发生MODS 6 6例的临床资料 ,并计算其A PACHEII评分。结果 :产科MODS患者诱因主要是产科因素 ,共 4 8例 (72 .73% ) ,死亡 7例 (14 .5 8% ) ,以重度子痫前期或子痫及产后出血为主 ;诱因 18例妊娠合并内外科疾病 ,死亡 11例 ,死亡率为 6 1.11% ,以妊娠合并心脏病和妊娠合并重症肝炎为主。产科MODS患者死亡率随着器官损害数的增多而上升 ,差异有显著性 (P <0 .0 5 ) ;随着器官损害数的增多 ,APACHEII评分逐渐升高 ,差异有显著性 (P <0 .0 5 ) ;APACHEII评分用于预测MODS死亡阳性率 ,2 ,3,4 ,5个器官受损害 ,其阳性率分别为 33.4 5 % ,5 7.12 % ,97.0 9% ,10 0 %。结论 :产科多器官功能障碍 /衰竭的产科主要诱因是重度子痫前期 /子痫 ,产后出血 ;产科MODS患者死亡率也随着器官损害数的增多而上升 ;APACHEII评分可在一定程度上作为评定产科MODS患者病情危重程度和预测预后的指标。  相似文献   
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