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61.
Introduction Failure to enter the coronary sinus (CS) with a guiding catheter and entering its tributaries remains challenging in left ventricle (LV) pacing lead implants for cardiac resynchronization therapy (CRT). A dual telescoping catheter system (8F outer/6F inner) is designed to provide the ability to adjust the catheter curve size, shape and/or reach to the patients’ anatomy avoiding the need for catheter change. Methods Five different designs for CS cannulation were randomly tested in 64 patients scheduled for CRT device implant. Results In 33 consecutive patients three adaptable telescoping guiding catheter systems were tested per patient, the adaptable catheters had higher overall cannulation success rates (68, 63 and 62%) compared to the fixed shape catheter (46%) and an greater cannulation success rate when the CS location was not known (70, 53 and 72% vs 33% for the fixed shape). In a second group of 31 CRT patients the two telescoping catheters had similar high levels of success (71–80%), with or without using the inner catheter. Conclusions The telescopic system is adaptable to a wide range of anatomical variations in patients and can result in a higher CS cannulation success rate due to its adjustability in the RA in search for the CS ostium. On top of this the inner catheter allows for sub-selecting the CS tributaries.  相似文献   
62.
FLAIR序列脑室内脑脊液搏动伪影(VCSFA)的表现及初步分析   总被引:1,自引:0,他引:1  
目的探讨FLAIR序列脑室内脑脊液搏动伪影的表现及其与年龄、性别、脑室大小的关系。方法对100例正常成人行头颅MR检查,并对FLAIR序列脑室内脑脊液搏动伪影(VCSFA)进行观察统计分析。结果VCSFA表现为脑室内轻微或明显高信号,在Ⅲ,Ⅳ脑室最常见,在不同年龄组存在明显差异(P<0.05),VCSFA组Ⅲ,Ⅳ脑室左右径大于无VCSFA组(P<0.05)。结论VCSFA是由反转延迟造成的,随着年龄增长及脑室增大,VCSFA出现频率增加,与性别无关。  相似文献   
63.
液膜的组成为:2%石油硫醚-4%多丁二酰亚胺-94%煤油,内相试剂为:1~2mol/L的氨水溶液。较为适宜的操作条件为:乳水比为1:3;内油比为0.8:1;外相硝酸浓度为0.5~1mol/L;常温操作。当料液中的银离子浓度小于800ppm时,一次提取率可达97%以上。本工艺具有分离速度快,效率高、选择性好等优点。  相似文献   
64.
Subjects cycled at a work load calculated to elicit 75% of maximal oxygen uptake on two occasions: the first to fatigue (34.5 ± 5.3 min; mean ± SE), and the second at the same workload and for the same duration as the first. Biopsies were obtained from the quadriceps femoris muscle before and immediately after exercise, and 5 min post-exercise. Before the first experiment, muscle glycogen was lowered by a combination of exercise and diet, and before the second, experiment muscle glycogen was elevated. In the low glycogen condition (LG), muscle glycogen decreased from 169 ± 15 mmol glucosyl units kg-1dry wt at to rest to 13 ± 6 after exercise. In the high glycogen condition (HG) glycogen decreased from 706 ± 52 at rest to 405 ± 68 after exercise. Glycogen synthase fractional activity (GSF) was always higher during the LG treatment. During exercise in the HG condition, those subjects who cycled for < 35 min (n= 3) had GSF values in muscle which were lower than at rest, whereas those subjects who cycled for > 35 min (n= 4) had values which were similar to or higher than at rest. Thus the change in GSF in muscle during HG was positively related to the exercise duration (r= 0.94; y = 254–17x + 0.3x2; P < 0.001) and negatively related to the glycogen content at the end of exercise (r=–0.82; y= 516–2x + 0.001x2; P < 0.05). During LG exercise GSF remained constant. GSF increased markedly after 5 min post-exercise in both HG and LG conditions. cAMP dependent protein kinase activity increased similarly during both LG and HG exercise and reverted to the preexercise values 5 min post-exercise. It is concluded that muscle contraction decreases GSF, but low glycogen levels can attenuate or abolish the decrease in GSF. The rapid increase of GSF during recovery from exercise does not require glycogen depletion during the exercise.  相似文献   
65.
Data relating to motor loss and swallowing difficulties in a community sample of 976 patients who suffered an acute stroke have been analysed. About 17% of patients seen within one week had no paralysis; at 6 months 48% of survivors had no paralysis and 9% had severe paralysis. The Motricity Index used to study motor loss related to functional loss and walking ability; it seems to be a simple valid measure of motor loss. Severe paralysis was associated with a high fatality rate, and only 6%-10% of survivors of an initially severe paralysis made a full recovery by 6 months. If severe persisted at 3 weeks, full recovery was not observed. Loss of sitting balance was associated with a poor outcome. Of conscious patients seen within one week, 14% choked on attempting to swallow and a further 28% had abnormal swallowing: this 42% of patients had a high fatality rate.  相似文献   
66.
目的 分析快速康复外科(FTS)理念在膀胱癌(BC)患者根治性全膀胱切除术围术期护理中的应用效果。方法 回顾性收集我院147例BC患者,均接受根治性全膀胱切除术治疗,将2017年1月~2018年10月在围术期接受常规护理干预的73例作为对照组,将2020年1月~2021年10月在围术期接受FTS理念干预的74例作为观察组,比较两组围术期情况、不同时间点(术前1d、术后1h、1d)疼痛程度、并发症。结果 观察组术后首次下床活动、术后首次排气以及住院时间均短于对照组(P<0.05);两组不同时间、组间、交互作用下视觉模拟疼痛评分(VAS评分)比较,差异具有统计学意义(P<0.05),两组术前1d VAS评分比较,无明显差异(P>0.05);而与对照组术后1h、1d VAS评分相比,观察组均较低(P<0.05);观察组、对照组并发症发生率分别为31.08%、41.10%,组间比较,无明显差异(P>0.05)。结论 FTS理念应用于BC患者,能减轻疼痛程度,缩短术后首次下床活动、术后首次排气时间,促进术后恢复。  相似文献   
67.
Long-term (3.5 years) immune reconstitution in relation to viral load response was determined. Plasma HIV-1 RNA was suppressed in 40 patients (full responders) up to 42 months, and 17 patients achieved partial response. The measurements of CD4+ and CD8+ T lymphocyte subsets (CD45RA, CD45RACD62L, CD45RO, CD28, CD38) were carried out by flow cytometry. Full responders had a significant increase of CD4+ and all CD4+ T subsets both up to 6 and from 6 to 42 months, while the increase for partial responders was only up to 6 months. By 6 months, higher slopes were observed in full versus partial responders in the % of CD28 on CD4+ and the % of CD4+ memory subset and in both naïve and memory CD4+ subsets from 6 to 42 months. The percentage of CD8+ and its subsets was decreased significantly in full responders both up to 6 and from 6 to 42 months (except for an increase in the CD8+CD45RA+ CD62L+ cells), while in partial responders this decrease was only up to 6 months. Lower slopes were observed in full versus partial responders from 6 to 42 months in the percentages of CD8+, CD8+CD45RO+, CD8+CD28, and CD8+CD38+ T cells. In conclusion, full responders have a stronger long-term naive CD4+ T cell subset reconstitution than partial responders. J. Med. Virol. 73:235–243, 2004. © 2004 Wiley-Liss, Inc.  相似文献   
68.
BackgroundKnee osteoarthritis (KOA) is increasingly prevalent in North American society. The significant societal burden it represents makes it essential to promote and target new treatments in earlier phases of the disease. Among others, subchondroplasty is a newly documented technique using calcium phosphate injection targeting the osteochondral lesions preceding KOA, also known as Bone Marrow Lesions (BMLs). This article aimed to review the existing literature on clinical and radiological outcomes of subchondroplasty in the treatment of BMLs in KOA.MethodA systematic review was performed using PubMed, Embase, Medline and Cochrane Database of Systematic Reviews. Studies on calcium phosphate injections into BMLs for KOA and its clinical and radiological outcomes were screened and reviewed by independent evaluators.ResultsAfter screening, ten articles were included, totaling 540 patients. Follow-up ranged from 6 months to 7 years. Overall, the procedure showed significant functional and quality of life improvement, as well as pain relief, as shown by Patients-Reported Outcomes Measures (PROMs). There were very few complications reported, the most important being leakage of calcium phosphate outside the targeted site. Conversion rate to total knee arthroplasty (TKA) ranged from 14 % to 30 % at 2 years post-procedure. Long term radiological outcomes have been poorly documented.ConclusionsSubchondroplasty is a promising avenue for the treatment of KOA. However, quality evidence is still required before any real conclusions and practical management guidelines can be drawn. Prospective, randomized studies with a control group and a rigorous assessment of long-term clinical and radiological outcomes are recommended.  相似文献   
69.
A new physical assay method for tobacco mosaic virus is described which incorporates two improvements on previous procedures. Losses of up to 75% of virus during extraction are corrected by adding a trace of radioactive virus to leaf samples before homogenization, and determining percentage recovery of radioactivity in final virus preparations. Estimation of virus concentration in partially purified preparations is from the first derivative (dA/d lambda) of the ultraviolet absorption spectrum, using a pronounced signal from the tryptophan fine-structure absorption band at 285-293 nm. This method is highly insensitive to ultraviolet-absorbing contaminants, which cause errors and increase variation between replicates, when estimation of virus concentration is by normal measurement of ultraviolet absorption (A260). The method can be applied to at least some other viruses.  相似文献   
70.
Summary Experiments were designed to determine whether leakage of substances across the tubular epithelium, which are impermeant in the normal kidney, falsifies the measurement of glomerular filtration rate in acute renal failure. Permeability to those substances most commonly used for filtration rate determination, polyfructosan, inulin and ferrocyanide, was estimated by measuring their recoveries following perfusion through various nephron segments in haeme pigment, ischaemic and nephrotoxic models of actue renal failure. Late proximal recovery of14C ferrocyanide was only marginally decreased compared to controls, by a maximum of 6%. Distal recovery of polyfructosan,14C and3H inulin were depressed somewhat more, by a maximum of 11%. Urinary recovery of14C inulin was reduced by only 15% in kidneys showing severely restricted renal function. It is concluded that tubular leakage is not a feature of significance in the early phase of moderate acute renal failure, that ferrocyanide and inulin are reliable markers for the determination of nephron filtration rate and water reabsorption, and that the reduction in whole kidney inulin or polyfructosan clearance reflects primarily a reduction in glomerular filtration rate.  相似文献   
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