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1.
Percutaneous transluminal balloon angioplasty (PTA) was performed in 17 tibial arteries with an average cross-sectional area stenosis of 92% (range 75–99%) in 13 patients (14 limbs) for limb salvage. In 4 of 14 lower extremities, PTA of femoropopliteal arteries was also performed. Technical success with 50% or less residual stenosis was achieved in all 17 tibial vessels. At approximately 2 months after PTA, clinical improvement had occurred in 10 of 14 limbs; no patient was made worse. Most recent follow-up (mean 19 months, range 8–34 months) revealed continued satisfactory clinical success with no further vascular intervention in 9 of these 10 limbs (one patient died). Short segmental stenoses, residual stenoses less than 40% following PTA, and absence of diabetes or gangrene appear to be predictors of favorable clinical outcomes. Our results suggest that PTA of focal tibial stenosis is an effective and safe treatment modality in properly selected patients and that wider use of PTA may be justified.  相似文献   
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Left ventricular aneurysm: a new surgical approach   总被引:16,自引:0,他引:16  
Since 1984, we have used a circular patch to reconstruct the left ventricle ("endoventricular circular plasty") in order to maintain a more physiologic cavity. This technique has three theoretical advantages over standard linear closure of the left ventricle (LV). First, it allows exclusion of the septal akinetic segment of the LV. Secondly, circular reorganization of the remaining LV muscle avoids the restraint caused by the linear suture closure and achieves a more physiologic LV cavity. Thirdly, circular plasty using the patch allows a complete resection of aneurysmal segments including resection of extensive subendocardial scar tissue, when appropriate, without critically compromising the cavity size. The technique involves the following steps: --Resection of dyskinetic or akinetic LV free wall and thrombectomy when indicated. --A dacron patch lined with pericardium is secured at the junction of the endocardial muscle and scarred tissue, thereby excluding non contractile portions of the LV and septum. --Myocardial revascularization is performed as indicated with particular attention paid to revascularizing the proximal left anterior descending segment. The group of patients forming this study includes 130 cases of LV reconstruction since 1984. The three main indications for surgery were angina (40%), cardiac failure (35%), arrhythmias (10%). There have been 8 hospital deaths, 4 late mortalities related to recurrence of cardiac failure in this group.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The rapid increase in body mass that often occurs following creatine (Cr) supplementation is believed to be due to intracellular water retention. The purpose of this study was to determine whether Cr consumption alters the magnetic resonance (MR) transverse relaxation (T(2)) distribution of skeletal muscle. Transverse relaxation can be used to model water compartments within a cell or tissue. In this double-blind study, subjects were asked to supplement their normal diet with creatine monohydrate (20 g day(-1) for 5 days) mixed with a grape drink (Creatine group, n = 7), or the grape drink alone (Placebo group, n = 8). Phosphorous MR spectroscopy was used to determine the effectiveness of the supplementation protocol. Subjects that responded to the Cr supplementation (i.e. showed a > 5 % increase in the ratio of the levels of phosphocreatine (PCr) and ATP) were placed in the Creatine group. Both proton MR imaging and spectroscopy were used to acquire T(2) data, at 1.89 T, from the flexor digitorum profundus muscle of each subject before and after supplementation. Following the supplementation period, the Creatine group showed a gain in body mass (1.2 +/- 0.8 kg, P < 0.05, mean +/- S.D.), and an increase in PCr/ATP ratio (23.8 +/- 16.4 %, P < 0.001). Neither group showed any changes in intracellular pH or T(2) calculated from MR images. However, the spectroscopy data revealed at least three components (> 5 ms) at approximately 20, 40 and 125 ms in both groups. Only in the Creatine group was there an increase in the apparent proton concentration of the two shorter components combined (+5.0 +/- 4.7 %, P < 0.05). According to the cellular water compartment model, the changes observed in the shorter T(2) components are consistent with an increase in intracellular water.  相似文献   
4.
Ambulatory blood pressure was studied as a function of posture, place, and mood in 131 subjects classified according to race, gender, and hypertensive status. The effect of posture was significant and explained a substantial proportion of within-subject variability. After controlling for posture, significant place and mood effects were observed when subjects were sitting but not when they were standing. Home vs. work differences in both systolic and diastolic blood pressure were significantly greater in Whites than in Blacks. Similar differences in systolic blood pressure were greater in mild hypertensive than in normotensive subjects. The results of this study underscore the need to control for effects of posture when interpreting ambulatory blood pressure readings.  相似文献   
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Retinoblastoma is an ocular tumor that occurs in young children, in either heritable or sporadic manner. The relative rarity of retinoblastoma, and the need for expensive equipment, anesthesia, and pediatric ophthalmologic expertise, are barriers for effective treatment in developing countries. Also, with an average age‐adjusted incidence of two to five cases per million children, patient number limits development of local expertise in countries with small populations. Lebanon is a small country with a population of approximately 4.5 million. In 2012, a comprehensive retinoblastoma program was formalized at the Children's Cancer Institute (CCI) at the American University of Beirut Medical Center, and resources were allocated for efficient interdisciplinary coordination to attract patients from neighboring countries such as Syria and Iraq, where such specialized therapy is also lacking. Through this program, care was coordinated across hospitals and borders such that patients would receive scheduled chemotherapy at their institution, and monthly retinal examinations and focal laser therapy at the CCI in Lebanon. Our results show the feasibility of successful collaboration across borders, with excellent patient and physician adherence to treatment plans. This was accompanied by an increase in patient referrals, which enables continued expertise development. However, the majority of patients presented with advanced intraocular disease, necessitating enucleation in 90% of eyes in unilateral cases, and more than 50% of eyes in bilateral cases. Future efforts need to focus on expanding the program that reaches to additional hospitals in both countries, and promoting early diagnosis, for further improvement of globe salvage rates.  相似文献   
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