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排序方式: 共有2092条查询结果,搜索用时 15 毫秒
91.
Chun Hay Ko Karen Li Pak Cheung Ng Kwok Pui Fung Raymond Pui-On Wong Kit Man Chui Goldie Jia-Shi Gu Edmund Yung Tai Fai Fok 《Toxicology in vitro》2008,22(5):1222-1227
Glucose-6-phosphate dehydrogenase (G6PD)-deficient subjects are susceptible to chemical-induced oxidative haemolysis. Little is known concerning the haemolytic properties of Chinese herbal medicine on G6PD-deficient subjects. Our objective was to investigate the pro-oxidative effect of 18 commonly used Chinese herbal medicine (CHM) on human G6PD-deficient red blood cells. G6PD-deficient (n=10) and normal (n=10) whole blood samples were incubated with water extracts of CHM. The resulting levels of reduced glutathione (GSH) and methaemoglobin (MetHb) were determined by biochemical assays. Rhizoma Coptidis significantly reduced GSH level by 48.9+/-5.4% (at 1 mg/mL) in the G6PD-deficient erythrocytes (P<0.001) compared with the respective control group without challenge. Similar dose-dependent responses were observed at higher concentrations of Cortex Moutan, Radix Rehmanniae, Radix Bupleuri, Rhizoma Polygoni Cuspidati and Flos Chimonanthi (P<0.01, 5-10 mg/mL). In addition, the levels of MetHb were elevated significantly when challenged with Rhizoma Coptidis (2.8 fold at 5 mg/mL) and Cortex Moutan (3.4 fold at 10 mg/mL). This is the first report on the pro-oxidative action of CHM on G6PD-deficient blood samples in vitro as demonstrated by the decrease of GSH and increase of MetHb. G6PD-deficient subjects should restrain from excessive consumption of these pro-oxidative herbs. 相似文献
92.
目的 寻找新的抗万古霉素耐药菌活性化合物。方法 首次采用固相法合成了分别用生物素(Biotin)和^125I标记的D-Ala-D-Lactate和D-Ala-D-Ala探针化合物以及18个结构限定性的多肽和多肽衍生物化学库,并建立了“一珠一化合物”组合正交筛选实验方法。结果 发现了一个新的体外抑制低水平万古霉素耐药菌的化合物(Enterococcus faecalis,ATCC 51299,MIC值为17.5mg/L)。该化合物对万古霉素敏感菌菌株的抑制活性为MIC6.25mg/L(Staphylococcus aurreus,ATCC 25923)。结论 “一珠一化合物”组合正交筛选方法可以用于研究小分子间的相互作用。 相似文献
93.
BACKGROUND: Although it is recognized that anxiety and depression are associated with frequent attendance in primary care, not all patients with these disorders attend frequently. The factors associated with general practice consultation in the important group of patients with anxiety and depressive disorders are not clear. OBJECTIVES: Our aim was to determine prospectively the factors which predict consultation rate in a cohort of patients with anxiety and depressive disorders in primary care. METHODS: A total of 148 adult patients with a depressive, anxiety or panic disorder (DSM-III criteria) were studied prospectively for 6 months to determine the factors which predicted consultation rate during this time. Measures at baseline included: the Psychiatric Assessment Schedule, Hamilton Depression Rating Scale, Life Events and Difficulties Schedule, Clinical Anxiety Scale, details of substance misuse and demographic data. The principal outcome measure was the number of consultations recorded in the GP records over the following 6 months. The variables associated with consultation rate were assessed by multiple regression analysis, with number of consultations as the dependent variable. RESULTS: The median consultation rate during the 6 months of the study was five (range: 1-22). Thirty per cent of the sample consulted seven or more times during the 6 months and 10% consulted 12 or more times. The regression analysis demonstrated that the following variables contributed to the best model: prior consultation rate, past psychiatric history, ongoing social difficulties, current level of alcohol consumption, total psychiatric symptom score and total anxiety score. These variables together accounted for 41% of the variance in consultation rate. CONCLUSION: The detection and rigorous treatment of psychiatric disorder, the provision of social support and interventions for alcohol dependence may help to reduce the frequency of consultation of anxious and depressed patients in primary care. Future research to identify additional variables which explain the major part of the variance in consultation rate may pave the way for novel treatment approaches to the phenomenon of frequent attendance. 相似文献
94.
The phonetic inventories of 122 typically developing Cantonese-speaking children, aged from 0;10 to 4;7, were examined in terms of feature distinctions. The applicability of Dinnsen. Chin, Elbert and Powell's implicational feature hierarchy to these data was investigated. Results show that modifications to the hierarchy are necessary for the Cantonese phonetic system. A revised hierarchy for Cantonese is proposed. Differences between this proposal and the original work are discussed. The implicational nature of the proposed hierarchy was also tested on longitudinal data from ten children (aged from 0;10 to 3;5 at the beginning of the study) over a 1 year period. The proposed hierarchy successfully predicted the route of sound change of these inventories. Implications for further research on feature development are discussed. 相似文献
95.
N J Buckels C Mulholland I Galvin D Gladstone J Cleland 《The Ulster medical journal》1988,57(2):161-166
Untreated massive pulmonary embolism is associated with a high mortality. Pulmonary embolectomy has been largely superceded by thrombolytic therapy, but there are cases in which pulmonary embolectomy remains the treatment of choice. We present three case reports and discuss the merits of the various treatments available for massive pulmonary embolism. The primary treatment of massive pulmonary embolism should be thrombolytic therapy, but for patients who are at risk of haemorrhage following surgery, who are in cardiogenic shock despite medical treatment, or fail to improve following cardiac arrest, then pulmonary embolectomy remains the treatment of choice. 相似文献
96.
Intestinal lamina propria T cells are believed to be derived, via the systemic circulation, from gut-associated lymphoid tissue. After migration into the lamina propria, T cells are capable of luminally directed migration following the loss of surface epithelial cells. For adhesion and migration within the extracellular matrix, T cells are likely to utilize the integrin family of adhesion molecules. The aim of this study was to quantitatively and qualitatively investigate the expression of α5 and α6 integrin subunits on the surface of human T cells that: (a) migrated out of the lamina propria, (b) remained resident within the matrix and (c) were present in the circulation. In both subpopulations of CD4 and CD8-positive T cells, from both normal and inflamed (inflammatory bowel disease) colonic mucosa, there were significantly fewer α5 and α6 -positive cells than in the peripheral blood. In addition, there were significantly fewer α6 integrin molecules on the surface of CD4 and CD8-positive lamina propria T-cell subpopulations, compared with those in the circulation. Our studies suggest that, following migration into the lamina propria, there is down-regulation of α5 and α6 integrin-subunit expression on the surface of T cells. Molecules other than members of very late activation antigen-5 (VLA-5) (α5 β1 ) and VLA-6 (α6 β1 ) families of adhesion molecules are likely to be important in interactions with extracellular components in the lamina propria of normal and inflamed human colonic mucosa. 相似文献
97.
More than 300 risk factors for coronary artery disease (CAD) have been described. There are important geographical and racial differences in both the prevalence of CAD and of potential risk factors. The purpose of this study was to determine the relationship between both the presence and extent of angiographically defined CAD in an Irish population and a spectrum of clinical risk factors, lipid profile and haemostatic variables. On univariate analysis, age, male gender, history of smoking, history of hypertension, total cholesterol, triglycerides, LDL, Cholesterol, the LDL:HDL ratio, apoprotein B-100 and the apoprotein B-100:A-II ratio were associated with the presence of CAD. However, in multivariate analysis only age, male gender, a history of smoking and the apoptrotein B-100: A-II ratio remained significantly associated with the presence of CAD. These same risk factors and apoprotein B-100 were significantly associated with the extent of CAD on multivariate analysis. In addition, apoprotein B-100 levels appeared to be associated with disease extent. When all significant variables associated with the presence or extent of CAD were analysed together in a multivariate model, they only accounted for 28% of the variability in the distribution of CAD. Thus, advancing age, male gender, cigarette smoking and apoprotein B-100 appear to be important correlates of the presence and extent of CAD in this selected population. However, in individual patients most of the variability in the distribution of occlusive CAD remains unexplained. 相似文献
98.
99.
100.
Lui SL Cheng SW Ng F Ng SY Wan KM Yip T Tse KC Lam MF Lai KN Lo WK 《Kidney international》2005,68(5):2375-2380
BACKGROUND. The International Society for Peritoneal Dialysis (ISPD) treatment guidelines for continuous ambulatory peritoneal dialysis (CAPD) peritonitis 2000 recommended the use of cefazolin plus ceftazidime as the initial empirical therapy in patients with residual renal function (RRF). However, this treatment regimen has not been compared with the conventional regimen of cefazolin plus netilmicin in prospective, randomized controlled trials. METHODS: Stable CAPD patients who developed clinical evidence of peritonitis were randomized to receive intraperitoneal (i.p.) cefazolin plus netilmicin or cefazolin plus ceftazidime once daily in the long dwell for 14 days. For patients with RRF (>1 mL/minute) before entry into the study (N= 50), RRF and 24-hour urine volume were measured at days 1, 14, and 42 after commencement of i.p. antibiotic treatment. RESULTS: One hundred and two patients were recruited into the study. The primary cure rates of i.p. cefazolin plus netilmicin and cefazolin plus ceftazidime were 66.7% and 64.7%, respectively. The overall cure rate for the 2 treatment regimens was 82.3% for both. Seven patients (14%) from each treatment group required removal of the dialysis catheters due to treatment failure. Relapse of peritonitis occurred in 2 patients (4%) in both treatment groups. Thirty-six patients with RRF at baseline achieved primary cure of their peritonitis by the assigned antibiotics. In this subgroup of patients, their RRF and daily urine volume showed significant reduction at day 14 and returned to near baseline values at day 42. The degree of reduction in RRF and urine volume did not differ significantly between the patients treated with cefazolin plus netilmicin and cefazolin plus ceftazidime. CONCLUSION: Intraperitoneal cefazolin plus netilmicin and cefazolin plus ceftazidime have similar efficacy as empirical treatment for CAPD peritonitis. In CAPD patients with RRF, significant but reversible reduction in RRF and 24-hour urine volume could occur after an episode of peritonitis, despite successful treatment by i.p. antibiotics. The effect of i.p. cefazolin plus netilmicin, or i.p. cefazolin plus ceftazidime on RRF in CAPD patients with peritonitis does not appear to be different. Our findings do not support the routine use of cefazolin and ceftazidime as the empirical treatment for CAPD peritonitis. 相似文献