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91.
Background Percutaneous coronary interventions (PCIs) in patients with multivessel coronary artery disease (CAD) may be staged or performed in a single session. No data exist about the relative safety and efficacy of these 2 strategies. Our aim was to compare short-term and long-term outcomes of patients with multivessel CAD who underwent PCI in 1 versus 2 sessions. Methods and Results The study included 264 consecutive patients who underwent treatment in our center during 1997 and 1998. PCI was conducted in a single session in 129 patients and was staged in 135 patients. The mean interval between the sessions in the staged group was 45.6 ± 22.3 days. The rates of major adverse cardiac events (MACEs) during in-hospital stay did not differ significantly between the staged (combined for both stages) and nonstaged groups (2.2% vs 4.6%; P = .28). A trend for lower event rates at 30-day (2.9% vs 6.9%; P = .13) and 1-year follow-up (26.1 vs 35.9; P = .08) favored the staged arm. Diameter stenosis ≥50% was found in 17% of patients in the staged group in the second session and was successfully retreated in most of them. No MACE occurred between the sessions. Multivariate analysis identified staging of the procedure as a single independent predictor of MACE at 1-year follow-up (P = .05). Conclusion Our results suggest that a practical staging strategy within 4 to 8 weeks is safe and allows for identification and treatment of potential excessive proliferative response in the previously intervened lesions during the second procedure. (Am Heart J 2002;143:1017-26.)  相似文献   
92.
We thank Drs Michalsen and Dobos for their comments. Restingheart rate is indeed a strong predictor of mortality in patientswith coronary artery disease.1  相似文献   
93.
Brugada phenocopies (BrP) are clinical entities that are etiologically distinct from true congenital Brugada syndrome (BrS). BrP are characterized by type 1 or type 2 Brugada electrocardiogram (ECG) patterns in precordial leads V1–V3; however, BrP are elicited by various underlying clinical conditions such as electrolyte disturbances, myocardial ischemia, or poor ECG filters. In this report, we describe the first case of clinically reproducible BrP which is important to the conceptual evolution of BrP.  相似文献   
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96.
Remembering important information is imperative for efficient memory performance, but it is unclear how we encode important information. The current experiment evaluated two non-exclusive hypotheses for how learners selectively encode important information at the expense of less important information (differential resource allocation and information reduction). To evaluate these hypotheses, we measured changes in learners’ pupil diameter and fixation durations while participants performed a selectivity task that involved studying lists consisting of words associated with different point values. Participants were instructed to maximize their score on a free recall task that they completed after studying each list. Participants’ pupils dilated more when studying high-valued than low-valued words, and these changes were associated with better memory for high-valued words. However, participants fixated equally on words regardless of their value, which is inconsistent with the information reduction hypothesis. Participants also increased their memory selectivity across lists, but changes in pupil diameter and differences in fixations could not account for this increased selectivity. The results suggest that learners allocate attention differently to items as a function of their value, and that multiple processes and operations contribute to value-directed remembering.  相似文献   
97.

Aims/hypothesis

Liraglutide can modulate insulin secretion by directly stimulating beta cells or indirectly through weight loss and enhanced insulin sensitivity. Recently, we showed that liraglutide treatment in overweight individuals with prediabetes (impaired fasting glucose and/or impaired glucose tolerance) led to greater weight loss (?7.7% vs ?3.9%) and improvement in insulin resistance compared with placebo. The current study evaluates the effects on beta cell function of weight loss augmented by liraglutide compared with weight loss alone.

Methods

This was a parallel, randomised study conducted in a single academic centre. Both participants and study administrators were blinded to treatment assignment. Individuals who were 40–70 years old, overweight (BMI 27–40 kg/m2) and with prediabetes were randomised (via a computerised system) to receive liraglutide (n?=?35) or matching placebo (n?=?33), and 49 participants were analysed. All were instructed to follow an energy-restricted diet. Primary outcome was insulin secretory function, which was evaluated in response to graded infusions of glucose and day-long mixed meals.

Results

Liraglutide treatment (n?=?24) significantly (p?≤?0.03) increased the insulin secretion rate (% mean change [95% CI]; 21% [12, 31] vs ?4% [?11, 3]) and pancreatic beta cell sensitivity to intravenous glucose (229% [161, 276] vs ?0.5% (?15, 14]), and decreased insulin clearance rate (?3.5% [?11, 4] vs 8.2 [0.2, 16]) as compared with placebo (n?=?25). The liraglutide-treated group also had significantly (p?≤?0.03) lower day-long glucose (?8.2% [?11, ?6] vs ?0.1 [?3, 2]) and NEFA concentrations (?14 [?20, ?8] vs ?2.1 [?10, 6]) following mixed meals, whereas day-long insulin concentrations did not significantly differ as compared with placebo. In a multivariate regression analysis, weight loss was associated with a decrease in insulin secretion rate and day-long glucose and insulin concentrations in the placebo group (p?≤?0.05), but there was no association with weight loss in the liraglutide group. The most common side effect of liraglutide was nausea.

Conclusions/interpretation

A direct stimulatory effect on beta cell function was the predominant change in liraglutide-augmented weight loss. These changes appear to be independent of weight loss.

Trial registration

ClinicalTrials.gov NCT01784965

Funding

The study was funded by the ADA.  相似文献   
98.
Efforts to understand the nature of “Not Just Right Experiences” (NJREs) have expanded the scientific understanding of obsessive–compulsive (OC) behavior. Approximately 80 % of unselected adults report experiencing NJREs and these experiences have been found to highly correlate with OC behavior. The purpose of this study was to assess NJREs in an unselected sample of adolescents (ages 14–17; N = 152), to compare their experience with adults (N = 237), and to assess the relation between NJREs and OC symptoms. Findings from questionnaires completed on the Internet were consistent with previous findings in adults, 81 % of adolescents endorsed recently having an NJRE. Some reactions differed according to age: adults reported NJREs as more frequent and adolescents endorsed feeling more compelled to respond. Surprisingly, OC symptoms were not significantly related to NJREs in the adolescents. Implications, limitations, and future directions for the study of NJREs in youth are discussed.  相似文献   
99.
Slow relaxation occurs in many physical and biological systems. "Creep" is an example from everyday life. When stretching a rubber band, for example, the recovery to its equilibrium length is not, as one might think, exponential: The relaxation is slow, in many cases logarithmic, and can still be observed after many hours. The form of the relaxation also depends on the duration of the stretching, the "waiting time." This ubiquitous phenomenon is called aging, and is abundant both in natural and technological applications. Here, we suggest a general mechanism for slow relaxations and aging, which predicts logarithmic relaxations, and a particular aging dependence on the waiting time. We demonstrate the generality of the approach by comparing our predictions to experimental data on a diverse range of physical phenomena, from conductance in granular metals to disordered insulators and dirty semiconductors, to the low temperature dielectric properties of glasses.  相似文献   
100.
Phagocytosis plays a critical role in both innate and adaptive immunity. Phagosomal fusion with late endosomes and lysosomes enhances proteolysis, causing degradation of the phagocytic content. Increased degradation participates in both innate protection against pathogens and the production of antigenic peptides for presentation to T lymphocytes during adaptive immune responses. Specific ligands present in the phagosomal cargo influence the rate of phagosome fusion with lysosomes, thereby modulating both antigen degradation and presentation. Using a combination of cell sorting techniques and single phagosome flow cytometry-based analysis, we found that opsonization with IgG accelerates antigen degradation within individual IgG-containing phagosomes, but not in other phagosomes present in the same cell and devoid of IgG. Likewise, IgG opsonization enhances antigen presentation to CD4(+) T lymphocytes only when antigen and IgG are present within the same phagosome, whereas cells containing phagosomes with either antigen or IgG alone failed to present antigen efficiently. Therefore, individual phagosomes behave autonomously, in terms of both cargo degradation and antigen presentation to CD4(+) T cells. Phagosomal autonomy could serve as a basis for the intracellular discrimination between self and nonself antigens, resulting in the preferential presentation of peptides derived from opsonized, nonself antigens.  相似文献   
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