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Background: In a prospective study design, we sought to assess the effect of dipyridamole on coronary flow parameters in patients with isolated coronary artery ectasia (CAE) as compared to subjects with normal coronaries. Methods: We enrolled 30 patients with ectasia of the left anterior descending (LAD) artery (study group), and 10 subjects with normal coronaries (control group). All subjects underwent transesophageal echocardiography to record flow velocities in the proximal LAD coronary artery, and velocity time integrals were calculated. The diameter of the proximal LAD coronary artery was measured and flow was calculated. Dipyridamole (0.56 mg/kg) was administered intravenously and measurements were repeated 5 minutes later. Results: At baseline, systolic and diastolic velocities, systolic, diastolic, and total velocity time integrals were significantly higher in the control group (P < 0.05 for all), yet, systolic, diastolic, and total coronary flow were significantly higher in the study group (P < 0.05 for all). Following dipyridamole administration, systolic, diastolic, and total coronary flow were still significantly higher in the study group (P < 0.05 for all), yet, there was no significant difference between the two groups regarding the other parameters, and regarding coronary reserve values (P > 0.05 for all). Conclusions: We concluded that patients with isolated CAE have a higher resting coronary flow as compared to control subjects with normal coronaries. Intravenous dipyridamole administration in these patients maintained a significantly higher coronary flow, with a coronary flow reserve similar to controls. (Echocardiography 2011;28:350‐357)  相似文献   
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Serum tumor marker CA15-3 is widely used in follow-up for assessment of breast cancer prognosis. The aim of this study was to evaluate levels among healthy females and patients, to assess differences with tumor stage and grade, and to determine the relationship with estrogen and progesterone receptor expression. One hundred and thirty six Jordanian females were enrolled in this study: Forty-five were healthy females; seventy-two were diagnosed with breast cancer and nineteen diagnosed with benign breast lesions. Elevated serum CA15-3 level was significantly observed among breast cancer patients (37.95±6.65) compared to both healthy (14.97±0.8) and benign females (12.30±1.55), but no significant association was detected between serum CA15-3 level and age of cancer onset, menarche age, menopause age, parity and BMI. Decreased CA15-3 level was significantly associated with hormone therapy and oral contraceptive consumption among breast cancer patients. Significantly elevated CA15-3 serum levels were found among grade II, III and stage II and III breast cancer females compared to normal healthy females. Elevated CA15-3 serum levels were also found among ER+/PR+ (54.242±7.89) and ER+/PR- (37.08±8.22) compared to healthy control females.  相似文献   
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OBJECTIVE: This study compared the effects of atypical antipsychotics (risperidone or quetiapine) with placebo and with each other in recently exacerbated patients with schizophrenia requiring hospitalization. METHODS: This international, randomized, double-blind study included a 2-week monotherapy phase followed by a 4-week additive therapy phase. Recently exacerbated patients with schizophrenia or schizoaffective disorder (DSM-IV) were randomized (2:2:1) to risperidone (n = 153), quetiapine (n = 156), or placebo (n = 73). Target doses were 4 or 6 mg/day of risperidone and 400 or 600 mg/day of quetiapine by day 5, with the ability to increase to 600 or 800 mg/day of quetiapine on day 8. The main outcome measures were the total Positive and Negative Syndrome Scale (PANSS) and need for additional psychotropic medications. RESULTS: Monotherapy Phase: The combined atypical antipsychotic group (n = 308) reached borderline superiority to placebo (n = 71) at the 2-week endpoint on mean change in total PANSS score (-24.1 +/- 1.2 and -20.2 +/- 2.0, respectively; p = 0.067). The change in the atypical group was driven by the improvement with risperidone (-27.7 +/- 1.5 vs. -20.2 +/- 2.0 with placebo, p < 0.01; and vs. -20.5 +/- 1.5 with quetiapine, p < 0.01); the improvement with quetiapine was similar to placebo, p = 0.879. Results were similar on other efficacy endpoints. Additive Therapy Phase: Additional psychotropics were prescribed to fewer (p < 0.01) risperidone (36%) than quetiapine (53%) or placebo patients (59%). The overall discontinuation rate was 18%, 26%, and 38%, respectively. Risperidone, compared with placebo, was associated with more parkinsonism, akathisia, plasma prolactin changes, and weight gain; while quetiapine was associated with more somnolence, sedation, dizziness, constipation, tachycardia, thyroid dysregulation, and weight gain. CONCLUSION: While the combined atypical antipsychotic group did not experience greater improvements than the placebo group, risperidone, but not quetiapine, was significantly superior in all measured domains to placebo in the management of recently exacerbated hospitalized patients with schizophrenia or schizoaffective disorder, with no unexpected tolerability findings.  相似文献   
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High-throughput sequencing platforms provide an approach for detecting rare HIV-1 variants and documenting more fully quasispecies diversity. We applied this technology to the V3 loop-coding region of env in samples collected from 4 chronically HIV-infected subjects in whom CCR5 antagonist (vicriviroc [VVC]) therapy failed. Between 25,000–140,000 amplified sequences were obtained per sample. Profound baseline V3 loop sequence heterogeneity existed; predicted CXCR4-using populations were identified in a largely CCR5-using population. The V3 loop forms associated with subsequent virologic failure, either through CXCR4 use or the emergence of high-level VVC resistance, were present as minor variants at 0.8–2.8% of baseline samples. Extreme, rapid shifts in population frequencies toward these forms occurred, and deep sequencing provided a detailed view of the rapid evolutionary impact of VVC selection. Greater V3 diversity was observed post-selection. This previously unreported degree of V3 loop sequence diversity has implications for viral pathogenesis, vaccine design, and the optimal use of HIV-1 CCR5 antagonists.  相似文献   
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The chemical reduction process of graphene oxide combined with a mild and controllable thermal treatment under vacuum at 200 °C for 4 hours provided a cost-effective, scalable, and high-yield route for Reduced Graphene Oxide (RGO) industrial production and became a potential candidate for producing electromagnetic interference (EMI) shielding. We investigated graphite, and RGO using l-ascorbic acid and Sodium borohydride before and after thermal treatment by carefully evaluating the chemical and morphological structures. The thermally treated l-ascorbic Acid reduction route (TCRGOL) conductivity was 2.14 × 103 S m−1 and total shielding efficiency (SET) based on mass loadings per area of shielding was 94 dB with about one-tenth less graphite weight and surpassing other graphene reduction mechanisms in the frequency range of 8.2–12.4 GHz, i.e., X-band, at room temperature while being tested using the waveguide line technique. The developed treatment represents valuable progress in the path to chemical reduction using a safe reducing agent and offering superior quality RGO rarely achieved with the top-down technique, providing a high EMI shielding performance.

The developed two-step protocol offers a superior reduced graphene oxide TCRGOL quality (7 layers), and its SET was 94 dB over the X-band.  相似文献   
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Maximum androgen blockade (MAB), consisting of an antiandrogen plus either a luteinizing hormone- releasing hormone agonist (LHRHA) or orchiectomy, is a standard care for patients with prostate cancer. Although, clinical trial results have been equivocal, none has shown a significant advantage in favor of MAB over castration alone in metastatic prostate cancer and MAB has been the subject of considerable controversy. The aim of this study was to compare MAB (orchiectomy or LHRHA"Goserelin") and anti-androgen "Bicalutamide" with castration alone (orchiectomy or LHRHA) in previ- ously untreated metastatic prostate cancer patients. Methods: Hundred eligible patients with adequate performance status and adequate hematologic, hepatic and renal functions were included. MAB arm, fifty patients underwent castration either surgically by orchiectomy or medically by receiving Goserelin (3.6 rag) depot, which was injected subcutaneously every 28 days plus bicalutamide 50 mg once daily. Castration alone arm, fifty patients underwent castration alone either surgically by orchiectomy or medically by receiving Goserelin (3.6 mg) depot. Results: During the period from January 2011 to January 2013, with a median follow up of 18 months (range 6 to 24 months), there were eight deaths (16%), in MAB arm and ten deaths (20%) in castration alone arm. At three months, there were 35 patients (70%) with prostate specific antigen (PSA) normalization (-〈 4 mg/dL) in MAB arm versus 17 patients (34%) with PSA normalization in castration alone arm (P = 0.001). The median progression free survival (PFS) times were 22.18 months (95% CI, 19.7 to 24.2 months) for MAB arm versus 22 months in castration alone arm (95% CI, 18 to 25.9 months; P = 0.045). The survival rates for MAB arm were 82% at 18 months and 70.6% at 24 months versus 78.7% at 18 months and 75.1% at 24 months in castration alone arm (P 〉 0.05). The median overall survival (OS) was not reached i  相似文献   
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