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排序方式: 共有1612条查询结果,搜索用时 15 毫秒
41.
Julie Teresa Marchesan Blake M. Warner Kevin Matthew Byrd 《Journal of periodontology》2021,92(10):1357-1367
Severe acute respiratorysyndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, has led to more than 3.25 million recorded deaths worldwide as of May 2021. COVID-19 is known to be clinically heterogeneous, and whether the reported oral signs and symptoms in COVID-19 are related to the direct infection of oral tissues has remained unknown. Here, we review and summarize the evidence for the primary infection of the glands, oral mucosae, and saliva by SARS-CoV-2. Not only were the entry factors for SARS-CoV-2 found in all oral tissues, but these were also sites of SARS-CoV-2 infection and replication. Furthermore, saliva from asymptomatic individuals contained free virus and SARS-CoV-2-infected oral epithelial cells, both of which were found to transmit the virus. Collectively, these studies support an active role of the oral cavity in the spread and transmission of SARS-CoV-2 infection. In addition to maintaining the appropriate use of personal protective equipment and regimens to limit microbial spread via aerosol or droplet generation, the dental community will also be involved in co-managing COVID-19 “long haulers”—now termed Post-Acute COVID-19 Syndrome. Consequently, we propose that, as SARS-CoV-2 continues to spread and as new clinical challenges related to COVID-19 are documented, oral symptoms should be included in diagnostic and prognostic classifications as well as plans for multidisciplinary care. 相似文献
42.
Dennis Wirth Brook Byrd Boyu Meng Rendall R. Strawbridge Kimberley S. Samkoe Scott C. Davis 《Biomedical optics express》2021,12(1):395
Whole-animal fluorescence cryo-imaging is an established technique that enables visualization of the biodistribution of labeled drugs, contrast agents, functional reporters and cells in detail. However, many tissues produce endogenous autofluorescence, which can confound interpretation of the cryo-imaging volumes. We describe a multi-channel, hyperspectral cryo-imaging system that acquires densely-sampled spectra at each pixel in the 3-dimensional stack. This information enables the use of spectral unmixing to isolate the fluorophore-of-interest from autofluorescence and/or other fluorescent reporters. In phantoms and a glioma xenograft model, we show that the approach improves detection limits, increases tumor contrast, and can dramatically alter image interpretation. 相似文献
43.
Accuracy of computed tomography to predict extracapsular spread in p16‐positive squamous cell carcinoma
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44.
The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) recommended a thiazide-like diuretic, alone or in combination with other antihypertensive drug classes, as initial therapy for hypertension. JNC 7, however, did not specify preferred combinations. The Avoiding Cardiovascular Events through Combination Therapy in Patients Living with Systolic Hypertension (ACCOMPLISH) trial was completed five years after the JNC 7 and demonstrated a 20 % advantage in cardiovascular risk reduction when blood pressure was lowered using the single-pill combination of benazepril-amlodipine compared to benazepril-hydrochlorothiazide (Jamerson et al. 359(23):2417–28 [1]). This new and significant finding provided compelling evidence that the long-standing preference for diuretics as initial therapy could be refuted, but it may also be relevant to the lower-than-expected reduction in coronary disease related events (compared to stroke) observed for decades prior to the ACCOMPLISH approach to therapy. The JNC 8 panel members recently published their recommendations, and while the group did not recommend benazepril-hydrochlorothiazide over other combinations, they did highlight the findings of ACCOMPLISH, rating the primary ACCOMPLISH paper as “good.” The American Society of Hypertension position paper and the European Hypertension Society guidelines endorse such combinations as a first-line agent for patients with stage 2 hypertension. We review the current position of ACCOMPLISH in the guidelines regarding treatment of stage 2 hypertension. 相似文献
45.
James B. Byrd MD MS Robert D. Brook MD 《Journal of clinical hypertension (Greenwich, Conn.)》2014,16(3):225-230
Ambulatory blood pressure monitoring (ABPM) offers advantages over clinic blood pressure measurement. Supporting the arm at the level of the right atrium has long been standard in clinic blood pressure measurement. In contrast, there is no consensus regarding arm position in the guidelines addressing ABPM. Research studies have used a variety of arm positions during ABPM. Discussed in this review are the merits of ABPM and a review of the several arm positions recommended in ABPM guidelines, suggested by cuff manufacturers, and used in research studies. To address this lack of standardization, a rationale for a clinically reasonable arm position during ABPM is offered. Specifically, the authors recommend advising the patient to keep the arm still and relaxed straight down at the side of the body when the cuff is going to inflate, when safe to do so. 相似文献
46.
Carrie Reed Dana Bruden Kathy K. Byrd Vic Veguilla Michael Bruce Debby Hurlburt David Wang Crystal Holiday Kathy Hancock Justin R. Ortiz Joe Klejka Jacqueline M. Katz Timothy M. Uyeki 《Influenza and other respiratory viruses》2014,8(5):516-523
Background
Highly pathogenic avian influenza A (HPAI) H5N1 viruses have infected poultry and wild birds on three continents with more than 600 reported human cases (59% mortality) since 2003. Wild aquatic birds are the natural reservoir for avian influenza A viruses, and migratory birds have been documented with HPAI H5N1 virus infection. Since 2005, clade 2.2 HPAI H5N1 viruses have spread from Asia to many countries.Objectives
We conducted a cross-sectional seroepidemiological survey in Anchorage and western Alaska to identify possible behaviors associated with migratory bird exposure and measure seropositivity to HPAI H5N1.Methods
We enrolled rural subsistence bird hunters and their families, urban sport hunters, wildlife biologists, and a comparison group without bird contact. We interviewed participants regarding their exposures to wild birds and collected blood to perform serologic testing for antibodies against a clade 2.2 HPAI H5N1 virus strain.Results
Hunters and wildlife biologists reported exposures to wild migratory birds that may confer risk of infection with avian influenza A viruses, although none of the 916 participants had evidence of seropositivity to HPAI H5N1.Conclusions
We characterized wild bird contact among Alaskans and behaviors that may influence risk of infection with avian influenza A viruses. Such knowledge can inform surveillance and risk communication surrounding HPAI H5N1 and other influenza viruses in a population with exposure to wild birds at a crossroads of intercontinental migratory flyways. 相似文献47.
48.
A 62-year-old woman was referred for evaluation of hypoxemia. Despite a resting SaO(2) of 89%, she was otherwise asymptomatic. The arterial blood gas on room air demonstrated a pO(2) of 58 mm Hg. Two shunt studies confirmed a shunt fraction of 25%. Echocardiogram with agitated saline demonstrated bubbles in the left atrium. Nuclear perfusion study revealed no uptake over the kidneys or brain. Computed tomography of the chest and cardiac magnetic resonance imaging confirmed the presence of a large shunt (azygous continuation of the inferior vena cava [ACIVC] with anomalous hepatic vein drainage). A large shunt fraction dictates either significant cardiac septal defect or an extracardiac shunt. The finding of ACIVC should prompt consideration of other vascular or cardiac abnormalities. The true incidence of isolated ACIVC is not known, as limited ACIVC may remain asymptomatic. However, the spectrum of vascular, cardiac and somatic abnormalities that may accompany ACIVC is quite varied. 相似文献
49.
50.
P Yan D Frankhouser M Murphy HH Tam B Rodriguez J Curfman M Trimarchi S Geyer YZ Wu SP Whitman K Metzeler A Walker R Klisovic S Jacob MR Grever JC Byrd CD Bloomfield R Garzon W Blum MA Caligiuri R Bundschuh G Marcucci 《Blood》2012,120(12):2466-2474
The outcome of older (≥ 60 years) acute myeloid leukemia (AML) patients is poor, and novel treatments are needed. In a phase 2 trial for older AML patients, low-dose (20 mg/m(2) per day for 10 days) decitabine, a DNA hypomethylating azanucleoside, produced 47% complete response rate with an excellent toxicity profile. To assess the genome-wide activity of decitabine, we profiled pretreatment and post treatment (day 25/course 1) methylomes of marrow samples from patients (n = 16) participating in the trial using deep-sequencing analysis of methylated DNA captured by methyl-binding protein (MBD2). Decitabine significantly reduced global methylation compared with pretreatment baseline (P = .001). Percent marrow blasts did not correlate with global methylation levels, suggesting that hypomethylation was related to the activity of decitabine rather than to a mere decrease in leukemia burden. Hypomethylation occurred predominantly in CpG islands and CpG island-associated regions (P ranged from .03 to .04) A significant concentration (P < .001) of the hypomehtylated CpG islands was found in chromosome subtelomeric regions, suggesting a differential activity of decitabine in distinct chromosome regions. Hypermethylation occurred much less frequently than hypomethylation and was associated with low CpG content regions. Decitabine-related methylation changes were concordant with those previously reported in distinct genes. In summary, our study supports the feasibility of methylome analyses as a pharmacodynamic endpoint for hypomethylating therapies. 相似文献