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71.
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Saquinavir boosted with low-dose ritonavir given with zidovudine and lamivudine was well tolerated by pregnant women and their infants. All mothers had <400 human immunodeficiency virus type 1 RNA copies/ml at delivery. Two had elevated liver transaminases and amylase. Seven infant adverse events were possibly treatment related (anemia, neutropenia, and hyperbilirubinemia).  相似文献   
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The activities of tigecycline alone and in combination with other antimicrobials are not well defined for carbapenem-intermediate or -resistant Acinetobacter baumannii (CIRA). Pharmacodynamic activity is even less well defined when clinically achievable serum concentrations are considered. Antimicrobial susceptibility testing of clinical CIRA isolates from 2001 to 2005 was performed by broth or agar dilution, as appropriate. Tigecycline concentrations were serially increased in time-kill studies with a representative of the most prevalent carbapenem-resistant clone (strain AA557; imipenem MIC, 64 mg/liter). The in vitro susceptibility of the strain was tested by time-kill studies in duplicate against the average free serum steady-state concentrations of tigecycline alone and in combination with various antimicrobials. Ninety-three CIRA isolates were tested and were found to have the following antimicrobial susceptibility profiles: tigecycline, MIC(50) of 1 mg/liter and MIC(90) of 2 mg/liter; minocycline, MIC(50) of 0.5 mg/liter and MIC(90) of 8 mg/liter; doxycycline, MIC(50) of 2 mg/liter and MIC(90) of > or =32 mg/liter; ampicillin-sulbactam, MIC(50) of 48 mg/liter and MIC(90) of 96 mg/liter; ciprofloxacin, MIC(50) of > or =16 mg/liter and MIC(90) of > or =16 mg/liter; rifampin, MIC(50) of 4 mg/liter and MIC(90) of 8 mg/liter; polymyxin B, MIC(50) of 1 mg/liter and MIC(90) of 1 mg/liter; amikacin, MIC(50) of 32 mg/liter and MIC(90) of > or =32 mg/liter; meropenem, MIC(50) of 16 mg/liter and MIC(90) of > or =128 mg/liter; and imipenem, MIC(50) of 4 mg/liter and MIC(90) of 64 mg/liter. Among the tetracyclines, the isolates were more susceptible to tigecycline than minocycline and doxycycline, according to FDA breakpoints (95%, 88%, and 71% of the isolates were susceptible to tigecycline, minocycline, and doxycycline, respectively). Concentration escalation studies with tigecycline revealed a maximal killing effect near the MIC, with no additional extent or rate of killing at concentrations 2x to 4x the MIC for tigecycline. Time-kill studies demonstrated indifference for tigecycline in combination with the antimicrobials tested. Polymyxin B, minocycline, and tigecycline are the most active antimicrobials in vitro against CIRA. Concentration escalation studies demonstrate that tigecycline may need to approach concentrations higher than those currently achieved in the bloodstream to adequately treat CIRA bloodstream infections. Future studies should evaluate these findings in vivo.  相似文献   
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Background

Diagnostic mIBG (meta-iodobenzylguanidine) scans are an integral component of response assessment in children with high-risk neuroblastoma. The role of end-of-induction (EOI) Curie scores (CS) was previously described in patients undergoing a single course of high-dose chemotherapy (HDC) and autologous hematopoietic cell transplant (AHCT) as consolidation therapy.

Objective

We now examine the prognostic significance of CS in patients randomized to tandem HDC and AHCT on the Children's Oncology Group (COG) trial ANBL0532.

Study design

A retrospective analysis of mIBG scans obtained from patients enrolled in COG ANBL0532 was performed. Evaluable patients had mIBG-avid, International Neuroblastoma Staging System (INSS) stage 4 disease, did not progress during induction therapy, consented to consolidation randomization, and received either single or tandem HDC (n = 80). Optimal CS cut points maximized the outcome difference (≤CS vs. >CS cut-off) according to the Youden index.

Results

For recipients of tandem HDC, the optimal cut point at diagnosis was CS = 12, with superior event-free survival (EFS) from study enrollment for patients with CS ≤ 12 (3-year EFS 74.2% ± 7.9%) versus CS > 12 (59.2% ± 7.1%) (p = .002). At EOI, the optimal cut point was CS = 0, with superior EOI EFS for patients with CS = 0 (72.9% ± 6.4%) versus CS > 0 (46.5% ± 9.1%) (p = .002).

Conclusion

In the setting of tandem transplantation for children with high-risk neuroblastoma, CS at diagnosis and EOI may identify a more favorable patient group. Patients treated with tandem HDC who exhibited a CS ≤ 12 at diagnosis or CS = 0 at EOI had superior EFS compared to those with CS above these cut points.  相似文献   
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BACKGROUND: Practice patterns for percutaneous coronary interventions (PCIs) may differ between Canada and the United States. Few data are available comparing PCI outcomes between the two countries in the era of coronary stenting and adjunctive glycoprotein IIb/IIIa inhibition. METHODS: In the Enhanced Suppression of the Platelet IIb/IIIa Receptor with Integrilin Therapy (ESPRIT) trial, 2064 patients were randomly assigned to receive eptifibatide or placebo during nonurgent PCI. The 30-day and one-year rates of death, myocardial infarction (MI) and target vessel revascularization (TVR) were compared between Canadian and American patients enrolled in the ESPRIT trial. RESULTS: There were 1531 American patients and 533 Canadian patients enrolled. Americans were older and heavier, and had a higher incidence of cardiac risk factors than Canadians (P<0.05 for all variables). Canadian patients had a lower incidence of death, MI and TVR at 30 days (6.2% versus 10.4%, P=0.004) and at one year (14.8% versus 21.5%, P=0.0006). After adjusting for known baseline differences, enrollment in Canada remained a significant predictor of reduced ischemic complications at 30 days (OR=0.53, c2=9.0, P=0.003). Similar results were observed at one year. Eptifibatide was superior to placebo in both groups of patients. CONCLUSIONS: This analysis is among the first to show Canadian patients to have fewer adverse events than American patients after nonurgent PCI. This effect was independent of known baseline differences between the patients in each country. The relative treatment effect of eptifibatide in Canadian patients paralleled that observed in the main ESPRIT trial and in American patients.  相似文献   
79.
OBJECTIVES: Papanicolaou (Pap) smears are an underutilized screening modality among racial and ethnic minorities. However, no data exist on Pap smear utilization among South Asians, a rapidly growing population in the United States, whose country of origin includes India, Pakistan, Bangladesh, and Sri Lanka. We determined rates and identified variables associated with Pap smear receipt by South Asians. DESIGN: A self-administered survey instrument was mailed to a random sample of South Asians nationwide over a 3-month time period. South Asian households were identified by surnames that were used to search white pages in telephone directories, Department of Motor Vehicle records, and voter registries. Questions regarding Pap smear receipt were taken from the 1999 National Health Interview Survey. Sociodemographic information and measures of acculturation were obtained. PARTICIPANTS: A nationwide nonprobability sample of South Asian women. INTERVENTION: Cross-sectional observational study. MEASUREMENTS AND MAIN RESULTS: The overall response rate was 42%. In this sample, South Asians belonged to a high socioeconomic strata (SES), with 45% having a household income of >$80,000 and 42% having a master's degree. Three quarters of the respondents (73%) reported having a Pap smear in the last 3 years. In multivariate logistic regression analysis, South Asian women had greater odds of having had a Pap smear if they were married (P <.001), more educated (P =.004), had a usual source of care (P =.002), and were more acculturated (P =.004). CONCLUSIONS: Despite the high SES of South Asian women, their rates of Pap smear receipt were lower than national recommendations. Marital status, socioeconomic status, and acculturation are all associated with Pap smear receipt. South Asian communities should be targeted for outreach to promote Pap smear utilization.  相似文献   
80.
Skeletal muscle function was measured as force production and fatigue in both the quadriceps (a large locomotive muscle) and adductor pollicis (a small intrinsic hand muscle) in five healthy volunteers, five patients with mild chronic heart failure, and five patients with severe chronic heart failure. The quadriceps of patients with chronic heart failure had a reduced muscle cross sectional area, a reduced maximum isometric force production, and an increased tendency to fatigue. Isometric force production and fatigue of the adductor pollicis, however, were not significantly different between the three groups under control conditions. But during circulatory occlusion fatigue in the adductor pollicis increased more in the patients with severe chronic heart failure. These differing findings in quadriceps and adductor pollicis suggest that skeletal muscle atrophy and reduced isometric force production are not a necessary consequence of chronic heart failure per se, because they were only present in the large locomotive muscle. The normal values for muscle fatigue observed in adductor pollicis in patients with chronic heart failure imply that skeletal muscle blood flow must increase normally during muscle activation when only a small muscle mass is used. These results are not compatible with the concept of a generalised impairment of normal vasodilatation within active skeletal muscle. In contrast, activation of a large muscle, such as quadriceps, results in the rapid onset of fatigue in patients with severe chronic heart failure. This fatigue may be related to the inability of the cardiovascular system to provide the required blood flow for the activation of a large muscle mass. The finding of a relatively greater increase in fatigue of adductor pollicis during circulatory occlusion in patients with severe chronic heart failure supports the hypnosis of an intrinsic abnormality of skeletal muscle in these patients.  相似文献   
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