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991.
Cardiovascular Drugs and Therapy - This Introduction sets the stage for 5 subsequent papers that will follow, and which describe several key features of the ISCHEMIA Trial in depth, including...  相似文献   
992.
Purpose

Pulmonary function testing (PFT) in patients with tracheostomies has been perceived as difficult to perform and clinically unreliable. We studied the feasibility, quality, repeatability and clinical significance of PFT.

Methods

Patients with tracheostomies that underwent PFT from January 1, 2010 to February 29, 2012 were identified. Clinical history and PFT data were reviewed retrospectively.

Results

Fifty patients (88% men) were identified. Forty-seven (94%) patients were able to perform PFT. Acceptable repeatability was obtained for FVC in 39 (83%) and for FEV1 in 41 (87%). Patients with tracheostomies showed difficulty in meeting ATS end-of-test criteria; only 9 (19%) met plateau criteria and 25 (53%) had exhalation times of greater than 6 s. Obstructive pattern was observed in 30 (64%) and restrictive pattern in 9 (19%). DLCO measurements were attempted in 43 patients and satisfactorily obtained in 34 (79%).

Conclusions

PFT can be performed with reliability in patients with tracheostomies, and they are useful for detecting and classifying types of lung dysfunction.

  相似文献   
993.
Copy number heterogeneity is a prominent feature within tumors. The molecular basis for this heterogeneity remains poorly characterized. Here, we demonstrate that hypoxia induces transient site-specific copy gains (TSSGs) in primary, nontransformed, and transformed human cells. Hypoxia-driven copy gains are not dependent on HIF1α or HIF2α; however, they are dependent on the KDM4A histone demethylase and are blocked by inhibition of KDM4A with a small molecule or the natural metabolite succinate. Furthermore, this response is conserved at a syntenic region in zebrafish cells. Regions with site-specific copy gain are also enriched for amplifications in hypoxic primary tumors. These tumors exhibited amplification and overexpression of the drug resistance gene CKS1B, which we recapitulated in hypoxic breast cancer cells. Our results demonstrate that hypoxia provides a biological stimulus to create transient site-specific copy alterations that could result in heterogeneity within tumors and cell populations. These findings have major implications in our understanding of copy number heterogeneity and the emergence of drug resistance genes in cancer.  相似文献   
994.
In July 2005, Argentina switched from a categorical liver allocation system to a MELD/PELD‐based policy for patients with CLD. To analyze WL outcomes and survival after LT in children. From January 2000 to December 2010, 923 children were registered. Two consecutive five‐yr periods were analyzed and compared: Era I (January 2000–July 2005) (n = 379) and Era II (July 2005–December 31, 2010) (n = 544). All data were prospectively collected and analyzed using the Kaplan–Meier method. After adopting the MELD/PELD system, WL registrations increased by 44% (from 379 to 544) and the number of LT increased by only 24% (from 278 to 365). However, three‐month WL mortality rate (32% to 18%, p < 0.0001, HR 2.002 CI 95% 1.5–2.8) decreased significantly. No significant differences were observed between Era 1 and II in one‐yr post‐LT survival (77.5% vs. 84.1%, p = 0.3053) and in acute re‐LT rate (9% vs. 5%, p = 0.1746). Under the MELD/PELD‐based allocation system in Argentina, mortality on the WL significantly decreased in children with CLD without affecting post‐LT survival, although reduced access to LT was observed.  相似文献   
995.

Introduction and objectives

To assess the effectiveness of direct oral anticoagulants vs vitamin K antagonists in real-life patients with atrial fibrillation.

Methods

A systematic review was performed according to Cochrane methodological standards. The results were reported according to the PRISMA statement. The ROBINS-I tool was used to assess risk of bias.

Results

A total of 27 different studies publishing data in 30 publications were included. In the studies with a follow-up up to 1 year, apixaban (HR, 0.93; 95%CI, 0.71-1.20) and dabigatran (HR, 0.95; 95%CI, 0.80-1.13) did not significantly reduce the risk of ischemic stroke vs warfarin, whereas rivaroxaban significantly reduced this risk (HR, 0.83; 95%CI, 0.73-0.94). Apixaban (HR, 0.66; 95%CI, 0.55-0.80) and dabigatran (HR, 0.83; 95%CI, 0.70-0.97) significantly reduced the major bleeding risk vs warfarin, but not rivaroxaban (HR, 1.02; 95%CI, 0.95-1.10), although with a high statistical heterogeneity among studies. Apixaban (HR, 0.56; 95%CI, 0.42-0.73), dabigatran (HR, 0.45; 95%CI, 0.39-0.51), and rivaroxaban (HR, 0.66; 95%CI, 0.49-0.88) significantly reduced the risk of intracranial bleeding vs warfarin. Reduced doses of direct oral anticoagulants were associated with a slightly better safety profile, but with a marked reduction in stroke prevention effectiveness.

Conclusions

Data from this meta-analysis suggest that, vs warfarin, the stroke prevention effectiveness and bleeding risk of direct oral anticoagulants may differ in real-life patients with atrial fibrillation.  相似文献   
996.
In 2014, the American Academy of Pediatrics (AAP) updated their recommendations for palivizumab prophylaxis for children who are at high risk for severe respiratory syncytial virus (RSV) infection. To investigate the potential impact of the more restrictive 2014 criteria on the eligibility for palivizumab prophylaxis, we applied the 2012 and 2014 AAP recommendations for palivizumab prophylaxis to a multicenter cohort of 2207 US children hospitalized for bronchiolitis. According to the 2012 AAP recommendations, 215 children (9.7%) were eligible for palivizumab prophylaxis, while 140 children (6.3%) would have been eligible based on the 2014 updated recommendations (34.9% relative decrease; 95%CI: 28.5–41.7%). The decrease was largely driven by the restriction of eligibility to preterm infants with gestational age <29 weeks. Further development of and refinement of cost‐effective approaches for the prevention of severe RSV infection are needed.  相似文献   
997.
BACKGROUND & AIMS: CCR5Delta32, a 32-base pair deletion of the CC chemokine receptor (CCR) 5 gene, is associated with slowed human immunodeficiency virus disease progression in heterozygotes and protection against infection in homozygotes. A recent study found a higher than expected frequency of CCR5Delta32/Delta32 in patients with hepatitis C virus infection. The roles of other disease-associated chemokine system polymorphisms have not been evaluated in hepatitis C virus infection. METHODS: Six chemokine system polymorphisms (CCR5Delta32, CCR5 promoter 59029-G/A, CCR2 -64I, RANTES [regulated upon activation, normal T cells expressed and secreted] -403 -G/A, and -28 -C/G and stromal derived factor 1 -3'A) were studied in 417 patients with liver diseases (339 with hepatitis C) and 2380 blood donors. The clinical parameters of hepatitis C virus infection were compared between carriers and noncarriers of each genetic variant. RESULTS: The frequency of CCR5Delta32 homozygosity was 0.8% in whites with hepatitis C virus and 1.1% in controls (P = 0.75). The CCR5Delta32 allele was not associated with any of the clinical parameters of hepatitis C virus infection. Hepatitis C virus-seropositive whites with the RANTES -403-A allele were less likely to have severe hepatic inflammation compared with those without (odds ratio, 0.34; P = 0.03). In multivariate analysis, the CCR5 promoter 59029 -A allele was marginally associated with a sustained response to interferon therapy (odds ratio, 3.07; P = 0.048). CONCLUSIONS: In this cohort, the frequency of CCR5Delta32 homozygosity in patients with hepatitis C was similar to controls. The high prevalence of CCR5Delta32 homozygosity in the hepatitis C virus patients of the earlier study likely reflects resistance to human immunodeficiency virus infection in hemophiliacs rather than a susceptibility to hepatitis C virus infection. Expression of CCR5 and RANTES may be important in the modulation of hepatic inflammation and response to interferon therapy in chronic hepatitis C.  相似文献   
998.
This study reviews the published research on night time eating, including the night eating syndrome (NES) and the nocturnal eating/drinking syndrome (NEDS). Studies were identified by a computerized literature search (PubMed, PsycInfo) and by references from the papers obtained. In addition, published abstracts from recent conferences in the areas of eating disorders and obesity were included. Individual studies were reviewed and their results summarized. Wakeful night time eating appears to be a frequent symptom which is more common among the obese. The data suggest an early age of onset with a chronic course in many patients. There appears to be considerable overlap between NES and NEDS. Treatment studies are sparse. The clinical features of these syndromes, their comorbidities, and their prevalence rates remain a matter of debate. It is unclear if the night eating syndrome presents a distinct entity that is of clinical relevance. The current nosologies may not capture the natural clustering of eating and sleep‐related pathology as it occurs in general population samples. Copyright © 2003 John Wiley & Sons, Ltd and Eating Disorders Association.  相似文献   
999.
During 1989-1999, 11 volunteers were immunized by the bites of 1001-2927 irradiated mosquitoes harboring infectious sporozoites of Plasmodium falciparum (Pf) strain NF54 or clone 3D7/NF54. Ten volunteers were first challenged by the bites of Pf-infected mosquitoes 2-9 weeks after the last immunization, and all were protected. A volunteer challenged 10 weeks after the last immunization was not protected. Five previously protected volunteers were rechallenged 23-42 weeks after a secondary immunization, and 4 were protected. Two volunteers were protected when rechallenged with a heterologous Pf strain (7G8). In total, there was protection in 24 of 26 challenges. These results expand published findings demonstrating that immunization by exposure to thousands of mosquitoes carrying radiation-attenuated Pf sporozoites is safe and well tolerated and elicits strain-transcendent protective immunity that persists for at least 42 weeks.  相似文献   
1000.
STUDY OBJECTIVES: The primary objective was to determine the safety and tolerability of repeated doses of aerosolized adeno-associated serotype 2 vector containing cystic fibrosis transmembrane conductance regulator (CFTR) complementary DNA (cDNA) [tgAAVCF], an adeno-associated virus (AAV) vector encoding the complete human CFTR cDNA. Secondary objectives included evaluation of pulmonary function assessed by spirometry, lung abnormalities by high-resolution CT (HRCT), airway cytokines, vector shedding, serum neutralizing antibody to AAV serotype 2 (AAV2), and gene transfer and expression in a subset of subjects undergoing bronchoscopy with bronchial brushings. DESIGN: Randomized, double-blind, placebo-controlled, phase II trial. SETTING: Eight cystic fibrosis (CF) centers in the United States. SUBJECTS: CF patients with mild lung disease, defined as FEV(1) > or =60% predicted. INTERVENTIONS: Subjects were randomized to inhale three aerosolized doses of 1 x 10(13) deoxyribonuclease-resistant particles of tgAAVCF or matching placebo at 30-day intervals using the Pari LC Plus nebulizer (PARI; Richmond, VA). Measurements and results: Of 42 subjects randomized, 20 subjects received at least one dose of tgAAVCF and 17 subjects received placebo. No difference in the pattern of adverse events or laboratory abnormalities was noted between the two treatment groups. Improvements in induced-sputum interleukin-8 (p = 0.03) and FEV(1) (p = 0.04) were observed at day 14 and day 30, respectively, in the group receiving tgAAVCF when compared to those receiving placebo. No significant differences in HRCT scans were noted. Vector shedding in sputum was observed at low levels up to 90 days after the third dose of vector. All subjects receiving tgAAVCF exhibited an increase (by at least fourfold) in serum AAV2-neutralizing antibodies and detectable levels in BAL fluid from five of six treated subjects undergoing BAL. Gene transfer but not gene expression was detected in a subset of six tgAAVCF subjects who underwent bronchoscopy. CONCLUSIONS: Repeat doses of aerosolized tgAAVCF were safe and well tolerated, and resulted in encouraging trends in improvement in pulmonary function in patients with CF and mild lung disease.  相似文献   
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