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According to social cognitive theory, this study explored the relationship between intrapreneurship and opportunity recognition. We developed a moderated mediation model of creative self-efficacy as a mediator and support for innovation as a moderator linking intrapreneurship with opportunity recognition. Using a sample of 206 college students from Chinese universities, we found that intrapreneurship is positively related to opportunity recognition, and this relationship was mediated by creative self-efficacy. Our research further found that the effect of intrapreneurship on opportunity recognition was conditional on support for innovation. Finally, the theoretical and practical implications are discussed.

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OBJECTIVE: To determine whether there is an association between the presence of asthma and a clinically aggressive disease course in patients with recurrent respiratory papillomatosis (RRP). DESIGN: Retrospective multi-institutional cohort study (level III evidence). SETTING: Two academic medical centers in the southeastern United States. PATIENTS: Adult patients with RRP treated at the Georgia Health Sciences University or at the Emory University School of Medicine between January 1998 and December 2009. Excluded from the study were adult patients who had been diagnosed as having RRP when they were a child (<18 years). MAIN OUTCOME MEASURES: The primary outcome measure was the presence of a clinically aggressive RRP disease course (defined as distal spread of disease, >4 procedures performed in 12 months, or progression to laryngeal squamous cell carcinoma). The secondary outcome measure was the frequency of required surgical interventions. RESULTS: Identified were 90 patients with RRP (age range at first diagnosis, 19.1-86.4 years). Seventeen patients had aggressive disease, and 73 patients had nonaggressive disease. Seven patients had a history of asthma, 5 of whom were using daily inhaled corticosteroids. An association was noted between the presence of asthma and aggressive RRP, which was found in 57% (4 of 7) of patients with asthma vs 16% (13 of 83) of patients without asthma (P = .02). Patients with asthma using daily inhaled corticosteroids were especially likely to have aggressive RRP, which was found in 80% (4 of 5) of corticosteroid users vs 15% (13 of 85) of nonusers (P = .004). CONCLUSIONS: Patients with asthma, particularly those using daily inhaled corticosteroids, may have a more clinically aggressive RRP course. The cause of this association is unclear, and clinical recommendations should not yet be made based on these data.

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OBJECTIVES/HYPOTHESIS: The goal of laryngeal framework surgery in patients with unilateral vocal fold paralysis is to improve glottic closure by medializing the paralyzed vocal fold. Type I thyroplasty (Th) and arytenoid adduction (AA) are two of the most commonly performed procedures. Two of the main rationales for performing an AA are to improve closure of the posterior glottis and correct vertical height discrepancy. The purpose of this study was to evaluate if AA with Th yields better posterior glottic closure and vertical height equality than Th alone. STUDY DESIGN: Retrospective. METHODS: Using visual analog scales, three blinded reviewers evaluated glottic closure patterns in patients who underwent Th or Th with AA. Pre- and postoperative videostroboscopic examinations of 45 patients with unilateral vocal fold paralysis, who underwent laryngeal framework surgery, were evaluated. RESULTS: No significant difference was identified in postoperative scores for midmembranous glottis closure (P=0.282), closure just anterior to the vocal processes (P=0.426), respiratory glottis closure (P=0.158), or vertical height discrepancy (P=0.113). CONCLUSIONS: Although larger glottic gaps and vertical height discrepancies may lead some surgeons to predict that an AA is warranted, the usefulness of AA may not always be related to these parameters. Ultimately, voice improvement and not geometry should guide the surgeon's decision making.

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OBJECTIVE: Sentinel lymph node (SLN) biopsy has shown great utility in the management of melanoma. An analysis of regional recurrence in previously mapped negative SLN basins as the first site of relapse is performed. METHODS: A retrospective query of a prospective melanoma database from 1994 to 2006 identified 1287 patients who underwent successful SLN biopsy. One thousand sixty patients (82.4%) were SLN negative and 227 (17.6%) patients SLN positive. Clinical variables were examined for the impact on regional recurrence by multivariate analysis. RESULTS: Mean follow-up was 44.3 months (range 3-155 months). Thirty-five patients (3.3%) presented with false-negative (FN) SLN biopsy. Pathologic review of the SLNs harvested from these basins found 7 (20.0%) samples positive for metastatic melanoma. Multivariate analysis found head and neck site [hazard ratio 3.67; 95% confidence interval (CI), 1.77-7.60, P < 0.001] and tumor thickness (hazard ratio 1.16; 95% CI, 1.04-1.30, P = 0.01) to be predictive of FN SLN biopsy. The 5-year melanoma specific survival calculated from the date of the SLN biopsy was 57.6% (95%CI, 35.7-41.9) in the FN group, which was not statistically different than the SLN positive group 60.0% (95% CI, 29.6-40.1; P = 0.14). CONCLUSIONS: Head and neck tumor site and tumor thickness are predictors of a FN SLN biopsy. Mechanisms other than pathologic SLN sampling error may contribute to the failure of the SLN biopsy in some patients. Patients with regional recurrence after negative SLN biopsy have a similar 5-year survival compared with patients with positive SLNs.

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BACKGROUND: The somatic DNA molecules of spirotrichous ciliates are present as linear chromosomes containing mostly single-gene coding sequences with short 5' and 3' flanking regions. Only a few conserved motifs have been found in the flanking DNA. Motifs that may play roles in promoting and/or regulating transcription have not been consistently detected. Moreover, comparing subtelomeric regions of 1,356 end-sequenced somatic chromosomes failed to identify more putatively conserved motifs. RESULTS: We sequenced and compared DNA and RNA versions of the DNA polymerase alpha (pol alpha) gene from nine diverged spirotrichous ciliates. We identified a G-C rich motif aaTACCGC(G/C/T) upstream from transcription start sites in all nine pol alpha orthologs. Furthermore, we consistently found likely polyadenylation signals, similar to the eukaryotic consensus AAUAAA, within 35 nt upstream of the polyadenylation sites. Numbers of introns differed among orthologs, suggesting independent gain or loss of some introns during the evolution of this gene. Finally, we discuss the occurrence of short direct repeats flanking some introns in the DNA pol alpha genes. These introns flanked by direct repeats resemble a class of DNA sequences called internal eliminated sequences (IES) that are deleted from ciliate chromosomes during development. CONCLUSION: Our results suggest that conserved motifs are present at both 5' and 3' untranscribed regions of the DNA pol alpha genes in nine spirotrichous ciliates. We also show that several independent gains and losses of introns in the DNA pol alpha genes have occurred in the spirotrichous ciliate lineage. Finally, our statistical results suggest that proven introns might also function in an IES removal pathway. This could strengthen a recent hypothesis that introns evolve into IESs, explaining the scarcity of introns in spirotrichs. Alternatively, the analysis suggests that ciliates might occasionally use intron splicing to correct, at the RNA level, failures in IES excision during developmental DNA elimination.

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During the course of a pilot genome project for the ciliate Oxytricha trifallax, we discovered a fusion gene never before described in any taxa. This gene, FSF1, encodes a putative fusion protein comprising an entire formaldehyde dehydrogenase (FALDH) homolog at one end and an S-formylglutathione hydrolase (SFGH) homolog at the other, two proteins that catalyze serial steps in the formaldehyde detoxification pathway. We confirmed the presence of the Oxytricha fusion gene in vivo and detected transcripts of the full-length fusion gene. A survey of other large-scale sequencing projects revealed a similar fusion protein in a distantly related ciliate, Tetrahymena thermophila, and a possible fusion of these two genes in the diatoms Phaeodactylum tricornutum and Thalassiosira pseudonana, but in the reverse order, with the SFGH domain encoded upstream of the FALDH domain. Orthologs of these fusion proteins may be widespread within the ciliates and diatoms.

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