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91.
We report one-year angiographic and intravascular ultrasound (IVUS) outcomes of in-stent restenosis (ISR) patients treated with intravascular brachytherapy (IVBT). The benefit of IVBT for treating ISR is well documented. However, few data exist on significant angiographic and intravascular ultrasonic in-stent lumen deterioration beyond the habitual 6-month analysis after the index radiation procedure or so-called late catch-up process in the treatment of ISR. Twenty-five consecutive patients with ISR were treated with IVBT using the Beta-Cath System (a 40 mm 90 Sr per 90 gamma source). Quantitative angiographic and IVUS analysis was performed in all of them at 6 and 12 months. IVBT was successful in all patients. Four patients (16%) developed recurrent angiographic binary restenosis at 6-month follow-up, all located within the adjacent reference segments, with 2 being associated with geographical miss. An additional 4 patients (16%) presented with recurrent ISR at 12-month follow-up, all within the stented segment. Significant in-stent lumen loss (0.16 +/- 0.42 mm to 0.34 +/- 0.46 mm; p = 0.008) and in-stent intimal hyperplasia growth (+11.2 +/- 0.48 mm3; p = 0.03) was observed between 6 and 12 months. Intracoronary beta-radiation for the treatment of ISR was associated with significant luminal deterioration (late catch-up) within the stents between 6 and 12 months due to an important late progression of in-stent intimal hyperplasia.  相似文献   
92.
BACKGROUND AND AIM OF THE STUDY: Thromboembolism and hemorrhage related to anticoagulation remain a major concern in elderly patients with mechanical valves. Clinical results following isolated aortic valve replacement (AVR) with tilting disk and bileaflet prostheses in patients aged over 70 years were analyzed and compared with results in patients aged <45 years. METHODS: Between January 1980 and August 2002, 319 consecutive older patients (group A) and 497 young patients AVR. Preoperative clinical data, early and late mortality, valve-related complications and data related to anticoagulation status (including mean INR and mean interval between INR assays) were compared between groups. RESULTS: Hospital mortality was lower in group B (3.4%) than in group A (10.7%; p <0.0001). Twelve-year actuarial survival was lower in older patients (54% in group A versus 78% in group B; p <0.001). The two groups showed similar 12-year actuarial freedom from hemorrhage (99.6% versus 99.5%; p = 0.69), endocarditis (99.6% versus 98.43%; p = 0.25) and perivalvular leak (99.6% versus 97.9%; p = 0.21). However, actuarial freedom from thromboembolism was lower in older patients (98.8% versus 99.7%; p = 0.041). CONCLUSION: Despite lower rates of long-term mortality and thromboembolism (the latter because of advanced atherosclerosis) in group A, there were no differences in rates of other valve-related complications. Hence, older age cannot be considered a contraindication to implantation of mechanical valves in the aortic position.  相似文献   
93.
The purpose of the study was to examine the safety and efficacy of two different formulations of mycophenolic acid (MPA)-eluting Duraflex stents on coronary de novo lesions. Recent data indicate that local delivery of MPA in the porcine overstretch coronary model significantly reduces neointimal hyperplasia (NIH). Patients were divided into three consecutive groups. The first (n=50) and second (n=55) groups received moderate- and slow-release MPA-eluting Duraflex stent, respectively. The last group (n=50) received the bare metal Duraflex stent. Clinical, angiographic, and intravascular ultrasound analysis were performed at 6-month follow-up. All stents were successfully deployed and patients were discharged home without clinical events. Compared to controls, 6-month in-lesion and in-stent minimum luminal diameter as well as late lumen loss were not significantly different in the moderate- and slow-release treatment groups. At follow-up, percentage obstruction and NIH volume were also similar between the three groups. At 30 days and 6 and 12 months, there were no differences noted between the three groups with respect to major adverse cardiac events as well as the individual rates of mortality, myocardial infarction, or repeat revascularization. There were no cases of subacute or late thrombosis. In this feasibility trial, the MPA-eluting Duraflex stents in either slow- or moderate-release formulations were well tolerated, but showed no benefit for treatment of coronary lesions when compared to controls. Further testing with different drug dosing or delivery rate might improve these results.  相似文献   
94.

Introduction

Immune response to vaccination in infants born prematurely may be lower than in infants born at full-term. Some clinical factors might be associated with humoral immune response.

Objectives

The objectives of this study were to compare the immune response to measles and varicella vaccination in infants born prematurely with those born at full-term and to analyze factors associated with measles and varicella antibody levels.

Methods

Prospective study including two groups of infants aged 12 months. One group of infants born prematurely with birth-weight <1500 g and who were in follow-up at the outpatient clinic for preterm infants at the institution and other group of infants born at full-term. Infants with malformations, primary immunodeficiency diseases, born to HIV-positive mothers or who had received plasma or immunoglobulin transfusions five months before or three weeks after vaccination were excluded. Plasma antibodies were measured by ELISA and factors associated with antibody levels were assessed by linear regression.

Results

Sixty-five premature and 56 full-term infants were included. The percentage of immune individuals after vaccination against measles (100% vs. 100%) and varicella (92.5% vs. 93.2%) were similar in both groups, as well as the antibody levels against measles (2.393 vs. 2.412 UI/mL; p = 0.970) and varicella (0.551 vs. 0.399 UI/mL; p = 0.114). Use of antenatal corticosteroids decreased measles antibody levels whereas breastfeeding for more than six months increased varicella antibody levels.

Conclusions

Humoral responses to measles and varicella were similar between infants born prematurely and full-term infants. Measles antibody levels were negatively associated with antenatal corticosteroid use; varicella antibodies were positively associated with prolonged breastfeeding.  相似文献   
95.
96.
97.
Epidermal growth factor receptor in human brain tumors.   总被引:3,自引:0,他引:3  
The expression of epidermal growth factor receptor (EGF-R) was examined in 27 primary human brain tumors (7 glioblastomas, 10 astrocytomas, 5 oligodendrogliomas, 1 schwannoma, 1 ganglioneuroma, 1 medulloblastoma, 1 ependymoma, 1 histiocytic lymphoma), in 6 brain metastases from lung carcinomas and in 20 meningiomas. Peritumoral tissues histologically normal excised surgically along with a large tumor were used as control. All plasma membranes from brain tissues tested showed specific EGF binding. The EGF receptor is expressed at low levels in the control human brain and at very high levels in 60% of the total intracranial tumors studied. When the various histological types of tumors were analyzed, the higher percentage of positive tumors was found with the meningiomas (85%) and the glioblastomas (71%), while the lower percentage of positivity was found with the oligodendrogliomas (40%) and the astrocytomas (30%). A good correlation between binding and total amount of EGF-R protein detected by Western Blot was also observed.  相似文献   
98.
Background: Ultrasound (US) examination of gallbladder is considered to be reliable, both in morphological and functional evaluation. We used US to study the gallbladder of a series of centenarians in order to show the characteristics of this organ in these subjects. We then compared the data obtained with two control populations omposed of elderly and adult subjects, respectively. Methods: US examination was done after an overnight fast and after emptying the gallbladder at 15-min intervals for a period of 90 min. To induce emptying of the gallbladder, we chose a semisolid meal with a small caloric value (370 kcal). The following parameters were evaluated: fasting gallbladder volume (in milliliters) before administration of the meal (considered to be 100%); gallbladder emptying (according to the formula: fasting gallbladder volume minus post-meal gallbladder volume at 10-min intervals divided by fasting gallbladder volume: the result of this operation was multiplied by 100); gallbladder motor functions, such as ejection volume (ml), is considered as the difference between fasting gallbladder volume and residual volume; ejection fraction (%), considered as the difference between fasting gallbladder volume and residual volume, is expressed as percentage fasting volume; and ejection rate (%/min) is calculated by dividing ejection fraction by time requested to reach the residual volume. Results: We found a common bile duct diameter that was significantly higher in centenarians than in the elderly and adults. Gallbladder wall thickness was significantly higher in centenarians than in adults. We also found substantially significant differences between centenarians with and without gallstones and elderly and adult subjects in the following parameters: mean gallbladder volume (reduced), residual volume (reduced), ejection volume (reduced) and ejection rate (reduced). The differences were not significant for the ejection fraction, and they were slightly reduced in centenarians compared to the other groups. There was a negative correlation between age and axial length (transverse diameter), age and width and age and common bile duct (CBD) diameter in the elderly group only. Conclusions: The study of gallbladder function in elderly people and centenarians is important because this parameter is related to the quality of digestion and absorption of many alimentary substances as well as to the formation of cholesterol gallstones. We found that gallbladder functions in centenarians are almost normal with respect to the elderly and adults. Contractility was higher than in our elderly sample. This fact ensures a correct concentration of bile salts and a good intestinal transit rate. It may represent one of the factors allowing for good digestive function in these subjects, which contributes to their health status.  相似文献   
99.
Persons with advanced human immunodeficiency virus type one (HIV-1) infection seek medical advice for a wide range of neurological disorders including, but not limited to, peripheral neuropathy, toxoplasmosis, cryptococcal meningitis, cytomegalovirus retinitis progressive multifocal leukoencephalopathy, lymphoma and dementia. The diagnosis of HIV-1-associated dementia (HAD) induced as a direct consequence of HIV infection of the brain comes commonly by exclusion. Diagnostic decisions can often be clouded by concomitant depression, motor impairments, and lethargy that follow debilitating immune suppression and weight loss. Indeed, cognitive, motor and behavior abnormalities underlie a variety of neurological dysfunctions associated with advanced HIV-1 infection. Thus, even combinations of clinical, laboratory and neuroimaging tests [for example, magnetic resonance imaging (MRI), computed tomography (CT), single photon emission computed tomography (SPECT) and positron emission tomography (PET)] often fail to provide conclusive diagnostic information. Nonetheless, the recent development of quantitative MR spectroscopic imaging has improved diagnostic possibilities for HAD. We are pleased to discuss these developments as well as taking a forward look into what will soon be made available to improve neuroimaging diagnostic precision. New MR and SPECT testing are being developed in our laboratories and elsewhere both for animal model systems and in humans with HIV-1 disease. Such tests can facilitate dynamic measures of HIV-1 neuropathogenesis providing information for disease events that even 2 years ago were unattainable.  相似文献   
100.
Clinical Oral Investigations - To assess the efficacy of three mechanical decontamination methods in four types of commercially available implants. Ninety-six implants of four commercial brands...  相似文献   
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