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61.
查耳酮类化合物对过敏性慢反应物质拮抗作用的构效关系   总被引:12,自引:1,他引:11  
查耳酮类化合物对过敏性慢反应物质拮抗作用的构效关系何克勤,程桂芳,奚凤德,郭宗儒,朱秀媛(中国医学科学院,中国协和医科大学药物研究所,北京100050)过敏性慢反应物质(SRSA),主要含白三烯C4(LTC4)、白三烯D4(LTD4)和白三烯E4(L...  相似文献   
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Three-hour biodistribution of Tc-99m complexes of six diphosphonates was compared in rabbits with tibial lesions to determine which was best for detection of focal bone lesions. Sr-85 was used as a standard. N,N-dimethylaminomethylene diphosphonate (DMAD) was the only agent with a higher lesion/normal bone ratio than methylene diphosphonate (MDP), attributable to lower concentration in normal bone. Hydroxymethane diphosphonate (HDP) and 2,3-dicarboxypropane-1, 1-diphosphonate (DPD) demonstrated higher concentration than MDP in normal bone without improving lesion contrast. They also exhibited much higher uptake in the liver and kidney, as well as muscle and red marrow in the case of DPD. None was superior to MDP as an all-purpose skeletal agent, though others may be better for specific applications.  相似文献   
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Regional wall motion (RWM) abnormalities are sensitive indicators of left ventricular (LV) dysfunction, but quantitation of RWM with gated radionuclide ventriculography (RVG) has been limited, particularly in the left anterior oblique (LAO) projection. Regional LV performance was studied in 18 patients undergoing LAO RVG immediately prior to contrast ventriculography (CVG). Wall motion was analyzed by semiautomated and visual methods using several coordinate systems. For semiautomated methods, RVG and CVG wall motion were closely related in the two 90 degrees polar sectors at the apex and posterior wall (r = .85) and in the five 45 degrees polar sectors from midseptum through posterior wall (r = .82). The basal sectors on RVG had weak relationship to CVG, due to adjacent vascular structures. Semiautomated and visual grades for polar sectors on both CVG and RVG were closely related (r = .88- .94). Measured regional wall motion on LAO RVG compared favorably with near-simultaneous CVG in nonoverlapping portions of the LV and allowed objective quantitation of regional LV performance.  相似文献   
66.

Background  

Major international differences in heart failure treatment have been repeatedly described, but the reasons for these differences remain unclear. National guideline recommendations might be a relevant factor. This study, therefore, explored variation of heart failure guideline recommendations in Europe.  相似文献   
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Background

Some UK GPs are acquiring access to natriuretic peptide (NP) testing or echocardiography as diagnostic tests for heart failure. This study developed appropriateness ratings for the diagnostic application of these tests in routine general practice.

Aim

To develop appropriateness ratings for the diagnostic application of NP testing or echocardiography for heart failure in general practice.

Design and setting

An appropriateness ratings evaluation in UK general practice.

Method

Four presenting symptoms (cough, bilateral ankle swelling, dyspnoea, fatigue), three levels of risk of cardiovascular disease (low, intermediate, high), and dichotomous categorisations of cardiovascular/chest examination and electrocardiogram result, were used to create 540 appropriateness scenarios for patients in whom NP testing or echocardiography might be considered. These were rated by a 10-person expert panel, consisting of GPs and GPs with specialist interests in cardiology, in a two-round RAND Appropriateness Method.

Results

Onward referral for NP testing or echocardiography was rated as an appropriate next step in 217 (40.2%) of the 540 scenarios; in 194 (35.9%) it was rated inappropriate. The ratings also show where NP testing or echocardiography were ranked as equivalent next steps and when one test was seen as the more appropriate than the other.

Conclusion

NP testing should be the routine test for suspected heart failure where referral for diagnostic testing is considered appropriate. An abnormal electrocardiogram status makes referral to echocardiography an accompanying, or more appropriate, next step alongside NP testing, especially in the presence of dyspnoea. Abnormal NP testing should subsequently be followed up with referral for echocardiography.  相似文献   
69.

Background

Management of pharyngitis is commonly based on features which are thought to be associated with Lancefield group A beta-haemolytic streptococci (GABHS) but it is debatable which features best predict GABHS. Non-group A strains share major virulence factors with group A, but it is unclear how commonly they present and whether their presentation differs.

Aim

To assess the incidence and clinical variables associated with streptococcal infections.

Design and setting

Prospective diagnostic cohort study in UK primary care.

Method

The presence of pathogenic streptococci from throat swabs was assessed among patients aged ≥5 years presenting with acute sore throat.

Results

Pathogenic streptococci were found in 204/597 patients (34%, 95% CI = 31 to 38%): 33% (68/204) were non-group A streptococci, mostly C (n = 29), G (n = 18) and B (n = 17); rarely D (n = 3) and Streptococcus pneumoniae (n = 1). Patients presented with similar features whether the streptococci were group A or non-group A. The features best predicting A, C or G beta-haemolytic streptococci were patient’s assessment of severity (odds ratio [OR] for a bad sore throat 3.31, 95% CI = 1.24 to 8.83); doctors’ assessment of severity (severely inflamed tonsils OR 2.28, 95% CI = 1.39 to 3.74); absence of a bad cough (OR 2.73, 95% CI = 1.56 to 4.76), absence of a coryza (OR 1.54, 95% CI = 0.99 to 2.41); and moderately bad or worse muscle aches (OR 2.20, 95% CI = 1.41 to 3.42).

Conclusion

Non-group A strains commonly cause streptococcal sore throats, and present with similar symptomatic clinical features to group A streptococci. The best features to predict streptococcal sore throat presenting in primary care deserve revisiting.  相似文献   
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