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排序方式: 共有667条查询结果,搜索用时 343 毫秒
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Wendell W Neeley Wendell A Edgin David A Gonzales 《Journal of oral and maxillofacial surgery》2007,65(6):1174-1179
PURPOSE: The purpose of this article is to inform the reader of the current literature regarding nasal airflow resistance. The anatomy and physiology of nasal airflow resistance will be examined and the known effects of widening of the nasal airway upon airflow will be described. MATERIALS AND METHODS: This article is a review of the current literature regarding nasal airflow and resistance and the effects of widening of the nasal base. No patient data were collected. RESULTS: The literature shows that nasal airflow resistance can be changed by surgical manipulation and by rapid palatal expansion, but that the effects on airflow resistance and future growth and development are unpredictable. CONCLUSION: Patients with a maxilla that is constricted in the transverse dimension and nasal airflow problems may benefit from expansion of the nasal base. The resultant effects upon nasal airflow resistance and subsequent growth and development are unpredictable and therefore airflow issues alone may not be a primary reason to increase the transverse dimension of the nasal base. 相似文献
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Sher Geoffrey; Feinman Michael; Zouves Christo; Kuttner Gordon; Maassarani Ghanima; Salem Rifaat; Matzner William; Ching Wendell; Chong Penny 《Human reproduction (Oxford, England)》1994,9(12):2278-2283
This study was undertaken to explore whether intervention withheparin and aspirin (H/A) in selected patients undergoing in-vitrofertilization (TVF) and embryo transfer could improve fecundityrates. Specifically, it explored the possibility that womendiagnosed with organic pelvic disease who demonstrated antiphospholipidantibodies (APA) could benefit from H/A administration in asimilar manner to that used in patients with recurrent pregnancyloss. We used an enzymelinked immunosorbent assay forsix different phospholipids to identify patients who expressedAPA before they underwent IVF/embryo transfer. This study wasconfined to the first IVF/embryo transfer cycle that followedassessment of APA status and accordingly, the number of IVF/embryotransfer cycles corresponds with the number of patients treated.APA seropositive patients were treated with aspirin, 81 mg orallyq.d., and heparin 5000 IU s.c. b.i.d., beginning on day 1 ofcontrolled ovarian stimulation. The endpoint for success wasa live birth or an ultrasound confirming fetal cardiac activity(a viable pregnancy). The prevalence of APA in patients diagnosedwith organic pelvic disease (53%) was much higher than in thosewithout female pathology (14%). The administration of H/A toAPA seropositive patients significantly (P < 0.05) improvedthe viable pregnancy rate (49%) compared to the untreated APAseropositive group (16%). The viable pregnancy rate for APAseropositive women treated with H/A was also significantly (P< 0.001) higher than for untreated APA seronegative patients(27%). We conclude that all women undergoing IVF/embryo transfershould be tested for APA prior to initiating ovarian stimulation,and those with APA seropositivity should be treated with H/A. 相似文献
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Marron Megan M. Moore Steven C. Wendell Stacy G. Boudreau Robert M. Miljkovic Iva Sekikawa Akira Newman Anne B. 《Age (Dordrecht, Netherlands)》2022,44(2):1083-1094
GeroScience - Apolipoprotein E (APOE) allelic variation is associated with differences in overall circulating lipids and risks of major health outcomes. Lipid profiling provides the opportunity for... 相似文献
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Han W. Kim Wolfgang G. Rehwald Elizabeth R. Jenista David C. Wendell Peter Filev Lowie van Assche Christoph J. Jensen Michele A. Parker Enn-ling Chen Anna Lisa C. Crowley Igor Klem Robert M. Judd Raymond J. Kim 《JACC: Cardiovascular Imaging》2018,11(12):1758-1769
Objectives
This study introduced and validated a novel flow-independent delayed enhancement technique that shows hyperenhanced myocardium while simultaneously suppressing blood-pool signal.Background
The diagnosis and assessment of myocardial infarction (MI) is crucial in determining clinical management and prognosis. Although delayed enhancement cardiac magnetic resonance (DE-CMR) is an in vivo reference standard for imaging MI, an important limitation is poor delineation between hyperenhanced myocardium and bright LV cavity blood-pool, which may cause many infarcts to become invisible.Methods
A canine model with pathology as the reference standard was used for validation (n = 22). Patients with MI and normal controls were studied to ascertain clinical performance (n = 31).Results
In canines, the flow-independent dark-blood delayed enhancement (FIDDLE) technique was superior to conventional DE-CMR for the detection of MI, with higher sensitivity (96% vs. 85%, respectively; p = 0.002) and accuracy (95% vs. 87%, respectively; p = 0.01) and with similar specificity (92% vs, 92%, respectively; p = 1.0). In infarcts that were identified by both techniques, the entire length of the endocardial border between infarcted myocardium and adjacent blood-pool was visualized in 33% for DE-CMR compared with 100% for FIDDLE. There was better agreement for FIDDLE-measured infarct size than for DE-CMR infarct size (95% limits-of-agreement, 2.1% vs. 5.5%, respectively; p < 0.0001). In patients, findings were similar. FIDDLE demonstrated higher accuracy for diagnosis of MI than DE-CMR (100% [95% confidence interval [CI]: 89% to 100%] vs. 84% [95% CI: 66% to 95%], respectively; p = 0.03).Conclusions
The study introduced and validated a novel CMR technique that improves the discrimination of the border between infarcted myocardium and adjacent blood-pool. This dark-blood technique provides diagnostic performance that is superior to that of the current in vivo reference standard for the imaging diagnosis of MI. 相似文献10.
J. Devon Roll Ashley G. Rivenbark Rupninder Sandhu Joel S. Parker Wendell D. Jones Lisa A. Carey Chad A. Livasy William B. Coleman 《Experimental and molecular pathology》2013
A subset of human breast cancer cell lines exhibits aberrant DNA hypermethylation that is characterized by hyperactivity of the DNA methyltransferase enzymes, overexpression of DNMT3b, and concurrent methylation-dependent silencing of numerous epigenetic biomarker genes. The objective of this study was to determine if this aberrant DNA hypermethylation (i) is found in primary breast cancers, (ii) is associated with specific breast cancer molecular subtypes, and (iii) influences patient outcomes. Analysis of epigenetic biomarker genes (CDH1, CEACAM6, CST6, ESR1, GNA11, MUC1, MYB, SCNN1A, and TFF3) identified a gene expression signature characterized by reduced expression levels or loss of expression among a cohort of primary breast cancers. The breast cancers that express this gene expression signature are enriched for triple-negative subtypes — basal-like and claudin-low breast cancers. Methylation analysis of primary breast cancers showed extensive promoter hypermethylation of epigenetic biomarker genes among triple-negative breast cancers, compared to other breast cancer subclasses where promoter hypermethylation events were less frequent. Furthermore, triple-negative breast cancers either did not express or expressed significantly reduced levels of protein corresponding to methylation-sensitive biomarker gene products. Together, these findings suggest strongly that loss of epigenetic biomarker gene expression is frequently associated with gene promoter hypermethylation events. We propose that aberrant DNA hypermethylation is a common characteristic of triple-negative breast cancers and may represent a fundamental biological property of basal-like and claudin-low breast cancers. Kaplan–Meier analysis of relapse-free survival revealed a survival disadvantage for patients with breast cancers that exhibit aberrant DNA hypermethylation. Identification of this distinguishing trait among triple-negative breast cancers forms the basis for development of new rational therapies that target the epigenome in patients with basal-like and claudin-low breast cancers. 相似文献