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131.
Som PM; Dillon WP; Fullerton GD; Zimmerman RA; Rajagopalan B; Marom Z 《Radiology》1989,172(2):515-520
Clinically assessed chronic proteinacious sinonasal secretions usually have long T1 and T2 relaxation times reflecting their high water content. However, in some cases variable combinations of short and long T1 and T2 relaxation times are found. To study the causes of these findings, the magnetic resonance (MR) images of 41 patients with surgically proved, chronically obstructed sinonasal secretions were studied. The relative signal intensities on both T1- and T2-weighted sequences of the sinus specimens were correlated with the gross viscosity of the specimens at surgery. Ten specimens were collected that were not contaminated with either blood or saline. UV spectrophotometric analysis of four of these samples excluded the presence of methemoglobin. Total protein content was determined in five samples, and in vitro T1 and T2 values were measured in one sample. These T1 and T2 relaxation times were accurately predicted with use of a standard pure lysozyme protein solution with the same concentration as the specimen. In addition, the observed T1- and T2-weighted signal intensities on the 41 MR images were predicted from an analysis of pure protein solutions. This study concludes that the primary causes of the variable T1 and T2 relaxation times of chronic sinonasal secretions are the macromolecular protein concentration, the amount of free water, and the specimen viscosity. Furthermore, an orderly and predictable transition of these signal intensities occurs over time. 相似文献
132.
2,4-二氨基-5-甲基-6-取代苄氨基喹唑啉衍生物的合成及其抗疟和抗肿瘤作用 总被引:2,自引:0,他引:2
本文报道2,4-二氨基-5-甲基-6-取代苄氨基喹唑啉衍生物的合成及其抗疟和抗肿瘤活性。这类化合物由5-甲基-2,4,6-三氨基喹唑啉与相应的取代苯甲醛缩合成Schiff碱,然后经还原,甲酰化或亚硝化制得。经对伯氏鼠疟原虫(Plasmodium berghei)抑制性治疗筛选,有三个化合物Ⅳ_(2,5,6)剂量5mg/kg×4d抑制率为100%;体外抗肿瘤活性以Ⅱ_7和Ⅳ_8最强,对L1210白血病细胞株的IC_(50)分别为3.910×10~(-3)μg/ml和6.172×10~(-3)μg/ml,与MTX相当。 相似文献
133.
134.
P Modi H Imura M Caputo AJ Parry A Pawade M-S Suleiman GD Angelini . 《Journal of cardiac surgery》2002,17(6):561-561
Aim: Ventricular septal defect(VSD) is the most frequently congenital heart disease. Some patients with VSD are accompanied by mitral insufficiency (MI). The post-operative MI is a much more important cause resulting in congestive heart failure. But it is still unclear whether MI will disappeared after VSD closure procedure. The purpose is to study the relationship between early VSD closure and the post-operative MI. Methods: 295 cases with VSD, MI were chosen for study from Feb. 1990 to Feb. 1998. Patients aged from 10 day to 12 year old, mean age was 2.6 year old. There were 223 patients with congestive heart failure(CHF). Results: MI was related to the severity of CHF, the more severe MI, the more severe CHF. The more large size VSD and left to right shunt, the more severe MI. 126 patients were performed surgical VSD close and 169 patients received medicine therapy including digoxin and captopril. There are no significant differences between two groups in age, sex, sevirity of MI before surgery. The follow-up period varied from 6 months to 34 months. After surgical VSD closure, MI disappeared in 99 patients, diminished in 5 patients, MI unchanged in 22 patients. After medicine therapy, MI disappeared in 69 patients, diminished in 13 patients, unchanged in 83 patients, and deteriorated in 12 patients. Conclusion: After surgical VSD closure in patients with VSD, MI, MI in most patients disappeared or diminished, but MI disappeared or diminished only in about half patients without surgical VSD closure, MI remained unchanged in a half patients and even worse in 12 patients. So early VSD closure is necessary for patients with VSD, MI. 相似文献
135.
136.
R Ascione K Rees MH Chamberlain F Ciulli AJ Bryan GD Angelini . 《Journal of cardiac surgery》2002,17(6):560-560
Aim: Saphenous vein (SV) is the most commonly used conduit in bypass procedures but has a one‐year occlusion rate of 15‐30%. A new ‘no‐touch’ technique where the SV is harvested with a cushion of surrounding tissue with no distension has led to improved early patency rates of 5% at 18‐months. Nitric oxide (NO), synthesised by nitric oxide synthase (NOS) has properties beneficial to graft patency. Our aim was to study the distribution of NOS in SV harvested by this technique and the effect of distension and removal of perivascular tissue on NOS content of SV. Methods: Following ethical committee approval and patients' informed consent, SVs were harvested from ten patients undergoing coronary artery bypass grafting. A segment of vein was harvested by the conventional technique (surrounding tissue stripped and vein distended with saline); another part was stripped but not distended (‘control’) and the remaining parts harvested by the ‘no‐touch’ technique. Samples of each segment were taken and transverse sections prepared for NOS identification using 3[H]L‐NG nitroarginine (NO Arg) autoradiography and NADPH‐diaphorase histochemistry. NOS isoforms were studied using standard immunohistochemistry. Endothelial cells and nerves were also identified using immunohistochemistry with CD31 and NF200 respecitvely, to confirm sources of NOS. Morphometric analysis of NADPH‐diaphorase staining was carried out to study tissue NOS content. Results: NO Arg binding representing NOS was preserved on the lumen of ‘no‐touch’ vessels whilst that on conventional and control vessels was reduced. NOS was also localised to the medial smooth muscle cells of all vein segments and to the intact adventitia of ‘no‐touch’ segments. This was confirmed by NADPH‐diaphorase staining, which revealed a mean reduction of NOS by 19.5% (p < 0.05, ANOVA) in control segments due to stripping of surrounding tissue alone and a reduction of 35.5% (p < 0.01, AVNOVA) in conventional segments due to stripping and distension, compared to ‘no‐touch’ segments. Adventitial NOS sources in ‘no‐touch’ vessels corresponded to vasa vasorum and paravascular nerves. All three NOS isoforms contributed to the preserved NOS in ‘no‐touch’ vessels. Conclusions: Apart from preserved lumenal NOS, NOS sources are also located in the media and adventitia of SV grafts. These are reduced by both adventitial damage and vein distension during conventional vein harvesting. The ‘no‐touch’ technique avoids these procedures, preserving NOS sources. This may result in improved NO availability in SV harvested by this technique, contributing to the improved patency rates reported. 相似文献
137.
The characteristic flow pattern of obstructed bile from the cannulation needle during percutaneous trans-hepatic cholangiography (PTC) or a biliary drainage procedure is described, and possible explanations and applications of this observation are discussed. 相似文献
138.
A new imaging format described here uses nonplanar reformations that follow the contour of curved structures intersected by a series of regularly spaced CT scans. The CT scanning procedure is described, and algorithmic details of this new format are presented. A standard set of reformatted images is suggested, and clinical examples are given to illustrate the diagnostic value of this new format. 相似文献
139.
140.
Exley AR; Carruthers DM; Luqmani RA; Kitas GD; Gordon C; Janssen BA; Savage CO; Bacon PA 《QJM : monthly journal of the Association of Physicians》1997,90(6):391-399
Because death after acute systemic vasculitis is now uncommon, alternative
measures of outcome are required. A significant component of patient
morbidity is disease-related damage, which can be quantified by the
Vasculitis Damage Index (64 items in 11 organ-based systems). We
investigated serially the time-course of damage in 120 patients with
systemic vasculitis, to determine the earliest indicators of outcome. High
damage scores at 2 years after presentation were characteristic of fatal
disease (OR 8.1-12.4). Significant damage occurred within 6 months of
presentation, and was a feature of fatal disease. More damage occurred
after presentation than after relapse. Lung and multi-system damage were
early indicators of poor outcome in severe non-fatal disease. Damage occurs
early in systemic vasculitis, and is an indicator of poor outcome. This
novel observation, together with evidence of persistent subclinical disease
activity and the high frequency of relapse, suggests a need for new
treatment strategies. Analogy with the management of acute leukaemia
suggests a strategy of early diagnosis and intensive induction of
remission, with early escalation of treatment for resistant disease.
相似文献