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71.

Background

To date, no published data are available regarding long‐term follow‐up of new generation DES implanted in coronary artery bypass graft (CABG) lesions.

Objectives

To assess the long‐term clinical outcome of patients receiving the new generation Biolimus A9‐coated drug‐eluting stent (DES) with biodegradable polymer in saphenous vein grafts (SVG).

Methods

Three thousand sixty‐seven patients were included in the NOBORI 2 registry: 71 patients with a total of 117 lesions received at least 1 biolimus A9 DES in SVG lesions and 2,959 patients received percutaneous coronary intervention in other lesions. Clinical follow‐up was performed at 1, 6, and 12 months, and annually up to 3 years.

Results

Compared to the non‐CABG group, patients with CABG lesions were older (P < 0.001), had a higher Charlson Comorbidity Index (P = 0.004), and presented more often with acute coronary syndrome (P = 0.02). At 3‐year follow‐up, cardiac death occurred in 9.7% versus 2.1% (P < 0.001), myocardial infarction (MI) in 8.3% versus 3.0% (P = 0.02), target lesion failure in 13.9% versus 6.4% (P = 0.03), and major adverse cardiac event in 18.1% versus 8.6% (P = 0.01). No differences were observed in TV‐MI and TLR, nor stent thrombosis (ST) which was generally low in both groups (1.4% vs 0.8%, P = NS).

Conclusion

Albeit 3‐year outcomes were less favorable in the CABG group, the higher cardiac mortality was apparently not driven by ST, target vessel MI, or TLR, but is likely due to advanced disease and age as well as comorbidity. The low TLR rate as well as the absence of late and very late ST suggest that BES are safe and effective for the treatment of CABG lesions. (J Interven Cardiol 2013;26:425‐433)
  相似文献   
72.
Abstract: Purpose: The purpose of this longitudinal whitening study was to determine the stability, post-treatment side effects, and patient satisfaction after 6 months of active treatment of tetracycline-stained teeth with 10% carbamide peroxide at 0 and 54 months post treatment.
Materials and Methods: Twelve patients who completed the study (80%) were contacted and asked to participate in a survey concerning their whitening experience. Subjects were asked whether there had been any change in the shade of their teeth after treatment, and if they had experienced any side effects that they believed were treatment-related. Eight of the twelve patients underwent clinical examination.
Results: Ten patients (83%) reported no obvious shade change or only a slight darkening not noticed by others. Two (17%) reported a slight darkening that is probably noticeable by other people, but no one reported moderate darkening or significant darkening back to original shade. All respondents (n = 12) denied having to have a crown or root canal that they believed was treatment-related. Examiners who compared preoperative and post-treatment photographs and Vita shade values were in agreement with the patients' perceptions of shade change. The degree of improvement was significant for both the immediate (0 mo) and the 54-month post-treatment comparison with the pretreatment shade (p < .005 and p < .01 respectively).  相似文献   
73.

Purpose

Tumor grade, deoxyribonucleic acid (DNA) ploidy, proliferation, p53 and bcl-2 expression were examined in clinically localized prostate cancers of black and white American men to learn whether these features showed racial differences.

Materials and Methods

A total of 117 prostate cancers (43 black and 74 white patients) obtained at radical prostatectomy for clinically localized disease were assigned Gleason scores by a single pathologist. Enzymatically dissociated nuclei from archival prostate cancers were examined by DNA flow cytometry using propidium iodide staining and the multicycle program to remove debris and sliced nuclei and to perform cell cycle analysis. For immunostaining after microwave antigen retrieval we used a DO-1/DO-7 monoclonal antibody cocktail for p53 and the clone 124 antibody for bcl-2.

Results

Significantly more black than white men had Gleason score 7 tumors. The DNA ploidy distribution of Gleason 6 or less tumors was similar for both races. As anticipated, the ploidy distribution of higher grade prostate cancer in white men was more abnormal but, unexpectedly, this was not found for higher grade prostate cancer in black men. No significant racial differences were found in S phase fractions, p53 or bcl-2 immunopositivity. However, for prostate cancer in black men there was a significant association between bcl-2 immunopositivity and higher S-phase fractions.

Conclusions

The aggressive prostate cancers of black men may be characterized by the 2 features of high proliferation and a block to programmed cell death.  相似文献   
74.
Chlordimeform [N'-(4-chloro-o-tolyl)-N,N-dimethylformamidine]has been shown to cause a 1-day delay in the surge of luteinizinghormone (LH) in ovariectomized, steroid-primed female rats,presumably through its ability to block CNS -noradrenergic receptorsand consequently CNS regulation of anterior pituitary function.In the present study, we determined whether a chlordimeform-induceddelay in the ovulatory surge of LH would alter pregnancy outcomein intact females. Chlordimeform (50 mg/kg) or sodium pentobarbital(35 mg/kg), as a positive control, was administered in orderto delay ovulation 24 (1-day delay) or 48 hr (2-day delay).Females were then housed with proven fertile males on the eveningof proestrus (0-day delay group), the following evening (1-daydelay group), or the evening after that (2-day delay group).The number of receptive females in each group, the mean lordosisquotient, and the number of sperm-positive females in each groupwere recorded. All females were killed on Gestation Day 20.The number of pregnant females in the 1- or 2-day delay groupswas reduced with both chlordimeform and pentobarbital. Also,delaying ovulation for 1 or 2 days with either compound resultedin a significant reduction in the number of live pups presenton Gestation Day 20 and a decrease in the number of implantationsites. Litter size was not affected if the females were matedon the same day that treatment was administered (0-day delay).Pentobarbital did not alter the proportion of females showingsexual behavior or the mean lordosis quotient in the 0- and1-day delay groups, although fewer 1-day females were spermpositive. The number of sexually active and sperm-positive femaleswas reduced in the 2-day pentobarbital-delayed group. However,the lordosis quotient of those that were sexually active wasnot different than that of control. Similarly, in CDF-treatedgroups, the proportion of females showing sexual activity wasreduced in the 0- and 2-day delayed groups. In contrast, sexualbehavior was lower in the 0-day delayed females when tested2 hr after lights out. These females did eventually mate, however,as confirmed by the high incidence of sperm positive smearsthe following morning. The number of sperm positive femaleswas lower in both the 1- and 2-day chlordimeform-induced delaygroups. Thus, brief exposures to compounds such as formamidinepesticide chlordimeform will result in not only a delay in breedingbut, more importantly, a significant reduction in litter size.  相似文献   
75.
The frequency of HL-A2 was significantly low (21%) in patients with periodontitis when compared to controls who were free of periodontal disease (61%). The effect was most pronounced in females in whom HL-A2 was present in 12.5% (2 out of 16). This finding suggests that genes controlling susceptibility to microbial agents may be linked to the HL-A LOCUS.  相似文献   
76.
A number of laminin isoforms have recently been identified and proposed to exert different functions during embryonic development. In the present study, we describe the purification and partial characterization of several isoforms isolated from chick heart and gizzard, and provide data on the molecular mechanisms underlying the interaction of avian neural crest cells with these molecules in vitro. Laminins extracted from heart and gizzard tissues were separated by gel filtration and purified to homogeneity by sequential lectin and immunoaffinity chromatography by utilizing monoclonal antibodies directed against the avian α2, β2 and γ1 laminin chains. The sodium dodecyl sulfate—polyacrylamide gel electrophoresis (SDS—PAGE) banding pattern of the polypeptide complexes obtained and immunoblotting with polyclonal antisera allowed the identification of Laminin-2 (α2β1γ1), Laminin-4 (α2β2γ1), and laminins comprising the β1, β2 and γ1 chains associated with a shorter α chain which, in SDS—PAGE, co-migrate with the β/γ complex in the 200 kDa region. These latter laminins, which are here arbitrarily denoted Laminin-αχ (heart tissue) and Laminin-G (gizzard tissue), are somewhat distinct in their apparent molecular weight, are differentially associated with nidogen, and appear as “T”-shaped particles similar to Laminin-6 and Laminin-7 when analyzed by transmission electron microscopy following rotary shadowing. In contrast, the avian Laminin-2 and Laminin-4 isoforms exhibit the characteristic cruciform shape described previously for their mammalian counterparts. Isolated neural crest cells differentially attached and migrated on these laminin isoforms, showing a clear preference for Laminin-G. Similarly to the EHS Laminin-1, neural crest cells recognized all avian isoforms through their α1β1 integrin, shown previously to be the primary laminin-binding receptor on these cells. Neural crest cell interaction with the avian laminins was dependent upon maintenance of the secondary and tertiary structure of the molecules, as shown by the marked reduction in cell attachment and migration upon disruption of the α-helical coiled-coil structure of their constituent chains. The results demonstrate that different laminin isoforms may be differentially involved in the regulation of neural crest cell migration and suggest that this regulation operates through interaction of the cells with a structurally conserved cell binding site recognized by the α1β1 integrin. Copyright © 1996. Published by Elsevier Science Ltd.  相似文献   
77.
78.
The factors that could reduce the size of particles generated by peripheral (8 Fr) and coronary (5 Fr) Kensey catheters (KC) in calcified and noncalcified atheroma were investigated. Fresh endarterectomy specimens (72 calcified, 72 noncalcified) were inserted in a flow circuit and randomized to undergo simulated dynamic angioplasty using 5 Fr or 8 Fr KC at a range of predetermined cam speeds (20,000–80,000 rpm) and flow rates (18–60 mL/min). Atherectomy as measured by weight loss from the specimen was greater in noncalcified lesions, 21.4 ± 4.5 mg and 14.9 ± 3.8 mg, respectively (P < 0.001). In calcified atheroma, the atherectomy was asymmetrical in 38 out of 72 specimens but in only 12 of 72 noncalcified lesions (P < 0.01). Overall, 65%± 3.9% of collected particles were smaller than 5 μm and 86.8%± 9.1% were smaller than 35 μm. In the remaining 13.2%± 8.9% of particles larger than 35 μm, significant differences were detected between the maximum particle size in each group. Larger particles were generated from calcified atheroma. In noncalcified lesions, increasing cam speed reduced maximum particle size from 890 to 170 μm (P < 0.001). Although a higher flow rate and the use of 5 Fr catheter have also significantly reduced the particle size, their effect was less than that exerted by cam speed. In calcified atheroma, cam speed was the only factor observed to influence the maximal particle size, reducing it from 1,260 to 381 μm (P < 0.001). In conclusion, although the majority of particles resulting from the use of KC were small, a proportion of large particles was also detected. Their size could be significantly reduced by careful adjustment of the operating parameters. These results are important for future application of KC in coronary dynamic angioplasty. However, the impact of reducing particle size on the risk of embolism in vivo requires further study.  相似文献   
79.
80.
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