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21.
The investigation of AUSTROLIABUM CANDIDUM afforded, in addition to several known sesquiterpene lactones, four new ones, including three germacranolides with an ether bridge, as well as an unusual glucoside. The structures were elucidated by spectroscopic methods. 相似文献
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23.
Minimally Invasive Coronary Artery Bypass Grafting: A New Method Using an Anterior Mediastinotomy 总被引:2,自引:0,他引:2
M. Clive Robinson M.D. David R. Gross D.V.M. Ph.D. William Zeman M.D. Eric Stedje-Larsen M.D. 《Journal of cardiac surgery》1995,10(5):529-536
The benefit of internal mammary artery (IMA) grafting as a long-lasting intervention for coronary artery disease is well recognized. However, largely because they are less invasive, catheter based alternatives are frequently chosen, particularly to treat single or double vessel disease. To retain the advantages of the IMA graft, and to offset the invasiveness of conventional coronary artery bypass grafting, we developed a new minimally invasive method using an anterior mediastinotomy for treating left anterior descending (LAD) or right coronary artery disease, or both. Feasibility studies using 16 pigs and a human cadaver led to approval by the Institutional Review Board for use of this procedure to treat six patients (four men, two women; mean age, 63.8 ± 13.6 [SD] yrs) who granted informed consent. Pedicle dissection of the IMA, using video assisted thoracoscopy if necessary, was made through a 2-to 3-inch horizontal anterior mediastinotomy. The underlying LAD artery was grafted during femoral vessel cardiopulmonary bypass, with cooling to 30°C, induced ventricular fibrillation, and left ventricular venting if required. Transesophageal echocardiography performed after bypass showed that two patients maintained normal wall motion and four had improvement from the original impairment. One patient suffered a recurrence of angina 4 weeks after the procedure; recatheterization showed an acutely angled IMA, subsequently corrected by balloon angioplasty. The results of follow-up dobutamine echocardiographic stress tests were negative in all patients. With this minimally invasive approach, the procedure should provide the benefits of IMA grafting with shorter hospital stay, more rapid recovery, and less overall cost. 相似文献
24.
The development and evaluation of a mu-capture ELISA detecting Chlamydia-specific IgM 总被引:2,自引:0,他引:2
T G Wreghitt V J Robinson E O Caul I D Paul S Gatley 《Epidemiology and infection》1988,101(2):387-395
A mu-capture enzyme-linked immunosorbent assay (ELISA) for detecting chlamydia-specific IgM was developed by use of the heat stable, lipopolysaccharide group-specific antigen and an alkaline phosphatase-labelled anti-chlamydia group-specific monoclonal antibody conjugate. The test was used to study the serological response in chlamydial respiratory tract infection among patients with acute respiratory tract symptoms in Cambridgeshire during the past 7 years. Results were compared with those of the complement fixation test (CFT) in routine use as well as those of a whole inclusion indirect immunofluorescence (WIF) test for IgM. Correlation between results of the mu-capture ELISA and those of the WIF test was 87.5%. The percentage of patients in whom specific IgM was found fell with increasing age. This may be due to lack of recall of IgM as a response to reinfection. Chlamydia-specific IgM was more likely to be detected when the CFT titre was greater than or equal to 64 and was rarely detected more than 6 months after the onset of symptoms. However, several patients less than 20 years of age were found to have specific IgM with CF antibody titres less than 64. We have found the mu-capture ELISA a useful test for the diagnosis of respiratory tract chlamydial infections, particularly in younger patients. 相似文献
25.
Postischemic renal dysfunction: the limited role of xanthine oxidase-generated oxygen free radicals 总被引:1,自引:0,他引:1
Oxygen free radicals (OFRs) generated during reperfusion are putative mediators of postischemic renal dysfunction. To address this issue, the renal response to ischemia and reperfusion was compared to the response to OFR generation without ischemia. Isolated rat kidneys were perfused at 37 degrees C and 90-100 mm Hg with an asanguinous modified Krebs' buffer. Kidneys were subjected to 30 min of ischemia followed by reperfusion or to OFRs generated by combining 25 mumole hypoxanthine with 1 unit xanthine oxidase. Both insults caused a 50% increase in vascular resistance. This was accompanied by a 30% reduction in perfusate flow rate and an 80% reduction in glomerular filtration and urine flow rates. The OFR scavengers, superoxide dismutase (SOD, 250 units/ml) and catalase (CAT, 500 units/ml), prevented these alterations after OFR generation but not after 30 min of ischemia and reperfusion. SOD and CAT also afforded no protection against the less severe dysfunction observed after 10 or 20 min of ischemia and reperfusion. OFRs do not appear to be prominent mediators of postischemic renal dysfunction; other factors, probably associated with ischemia must be primarily responsible. 相似文献
26.
27.
D J Flournoy M C Robinson 《Methods and findings in experimental and clinical pharmacology》1990,12(8):541-544
Three hundred and forty-nine methicillin resistant Staphylococcus aureus (MRSA) isolates from veterans were tested (by disc agar diffusion) for their in vitro activity against 18 antimicrobial agents. At least 90% of the isolates were susceptible to bacitracin, nitrofurantoin, hydrogen peroxide, novobiocin, netilmicin and vancomycin. We feel that the aminoglycoside, netilmicin, might provide an alternative agent (to intravenously administered vancomycin) for treating multiply-antimicrobial resistant MRSA. In addition, hydrogen peroxide exhibited very good activity against the test isolates and may have some use as a topical agent for reduction of MRSA on skin and some mucous membranes. This study suggests that further evaluation of netilmicin and hydrogen peroxide (topical only) might be useful. 相似文献
28.
Choc Miles G. Hsuan Francis Honigfeld Gilbert Robinson William T. Ereshefsky Larry Crismon Miles L. Saklad Stephen R. Hirschowitz Jack Wagner Richard 《Pharmaceutical research》1990,7(4):347-351
Clozapine plasma levels were monitored in 16 patients during a series of three consecutive treatments (single dose-multiple dose-single dose). Each patient received a single 75-mg dose (3 x 25 mg) with clozapine tablets, and serial plasma samples were collected over 48 hr after the dose. At 48 hr, a multiple-dose regimen was started, consisting of an initial dose escalation period followed by dosing at a constant regimen for at least 6 days. After the last dose, serial plasma samples were again obtained over 72 hr. Drug was then withheld for at least 7 days, a final single 75-mg dose was given, and plasma sampling was repeated. A subset of the patient population (N = 7) was used to test for a food effect during the single-dose treatments. The pharmacokinetic parameters between the initial and the final single dose periods were not significantly different. Similarly, there were no differences within patients when given the dose after fasting (fed 1 hr after dose) or with a meal. In contrast, the terminal elimination rate differed between the single-dose and the multiple-dose treatments (t1/2 m3 = 7.9 hr single dose and 14.2 hr multiple dose) (P less than 0.05) and the dose-normalized area under the plasma concentration/time curves increased 27% with multiple dosing. Since a previous study in patients (Choc et al., Pharm. Res. 4:402-405, 1987) showed dose proportionality of clozapine plasma concentrations during multiple-dose regimens, the present results cannot be described by Michaelis-Menten kinetics. 相似文献
29.
30.
Current methods of predicting prognosis in transitional cell carcinoma of the bladder fail to provide consistently reliable information about future tumour behaviour. The monoclonal antibody Ki67 recognises an antigen present in actively dividing cells and Ki67 reactivity has been shown to correlate with conventional prognostic indicators in several tumours. In this study, Ki67 antibody was used to determine the proportions of cells undergoing active division in 26 transitional cell carcinomas of the bladder. The proportion of cells stained in muscle invasive tumours (12.3 +/- 5.4%) was significantly greater than in superficial tumours (4.3 +/- 1.9%) and poorly differentiated tumours showed significantly greater proportions of cells staining compared with well or moderately well differentiated tumours. These results show that Ki67 reactivity correlates with high tumour stage and poor differentiation. Ki67 staining provides an easy method of determining tumour cell turnover that might provide additional prognostic information. 相似文献