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排序方式: 共有8050条查询结果,搜索用时 31 毫秒
1.
Alastair JS Webb Amy Lawson Linxin Li Sara Mazzucco Peter M Rothwell for the Oxford Vascular Study Phenotyped Cohort 《Journal of cerebral blood flow and metabolism》2021,41(6):1463
Cerebral arterial pulsatility is strongly associated with cerebral small vessel disease and lacunar stroke yet its dependence on central versus local haemodynamic processes is unclear. In a population-based study of patients on best medical managment, 4–6 weeks after a TIA or non-disabling stroke, arterial stiffness and aortic systolic, diastolic and pulse pressures were measured (Sphygmocor). Middle cerebral artery peak and trough flow velocities and Gosling’s pulsatility index were measured by transcranial ultrasound. In 981 participants, aortic and cerebral pulsatility rose strongly with age in both sexes, but aortic diastolic pressure fell more with age in men whilst cerebral trough velocity fell more in women. There was no significant association between aortic systolic or diastolic blood pressure with cerebral peak or trough flow velocity but aortic pulse pressure explained 37% of the variance in cerebral arterial pulsatility, before adjustment, whilst 49% of the variance was explained by aortic pulse pressure, arterial stiffness, age, gender and cardiovascular risk factors. Furthermore, arterial stiffness partially mediated the relationship between aortic and cerebral pulsatility. Overall, absolute aortic pressures and cerebral blood flow velocity were poorly correlated but aortic and cerebral pulsatility were strongly related, suggesting a key role for transmission of aortic pulsatility to the brain. 相似文献
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Rachel A. Katzenellenbogen Joseph J. Carter Joshua E. Stern Melinda S. Butsch Kovacic Parinda A. Mehta Sharon L. Sauter Denise A. Galloway Rachel L. Winer 《Clinical and Vaccine Immunology : CVI》2015,22(4):413-420
Persons with Fanconi anemia (FA) are at risk for human papillomavirus (HPV)-associated cancers; however, their natural HPV exposure and infection rates are unknown as is the adequacy with which they mount antibodies to HPV vaccination. This study aimed to determine, in 62 persons with FA, the seroprevalence of skin and mucosal HPV types, the seroprevalence in individuals self-reporting a history of HPV vaccination, and the factors associated with HPV seropositivity. A bead Luminex assay was used to determine seropositivity for HPV1, -2, and -4 (low-risk skin), -6 and -11 (low-risk mucosal, included in one HPV vaccine), -16 and -18 (high-risk mucosal, included in both HPV vaccines), and -52 and -58 (high-risk mucosal). Health- and behavior-related questionnaires were completed. Type-specific seroprevalence estimates and participant characteristics associated with seroprevalence were calculated; 48% reported HPV vaccination. Type-specific seropositivity in unvaccinated persons ranged from 7 to 21% for skin HPV types and 7 to 38% for mucosal HPV types. Among the unvaccinated participants, adults versus children demonstrated increased HPV1, -6, -16, and -58 seroprevalence of 45% versus 6%, 64% versus 22%, 64% versus 17%, and 36% versus 0%, respectively (all P < 0.05). The vaccinated participants versus the nonvaccinated participants demonstrated increased seroprevalence of HPV6, -11, -16, and -18 of 92% versus 38%, 92% versus 24%, 96% versus 34%, and 75% versus 7%, respectively (all P < 0.0001). Our data demonstrate that the unvaccinated participants had serologic evidence of prior skin and mucosal HPV infections and that seroprevalence increased among adults; in self-reported vaccinees, seroprevalence of HPV vaccine types was 75 to 96%. 相似文献
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Jesse Mez MD MS Daniel H. Daneshvar MD PhD Bobak Abdolmohammadi BA Alicia S. Chua MS Michael L. Alosco PhD Patrick T. Kiernan BA Laney Evers BA Laura Marshall BA Brett M. Martin MS Joseph N. Palmisano MS Christopher J. Nowinski PhD Ian Mahar PhD Jonathan D. Cherry PhD Victor E. Alvarez MD Brigid Dwyer MD Bertrand R. Huber MD PhD Thor D. Stein MD PhD Lee E. Goldstein MD PhD Douglas I. Katz MD Robert C. Cantu MD Rhoda Au PhD Neil W. Kowall MD Robert A. Stern PhD Michael D. McClean MS ScD Jennifer Weuve MPH ScD Yorghos Tripodis PhD Ann C. McKee MD 《Annals of neurology》2020,87(1):116-131
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Helen D Rodd Emma L Clark Melanie R Stern Sarah R Baker 《The Cleft palate-craniofacial journal》2007,44(1):92-94
OBJECTIVE: To determine the frequency of missed dental appointments among children with a cleft lip and/or palate (CL/P). DESIGN: A prospective study of failed appointments over a 12-month period. SETTING: Three different CL/P clinics within a British dental hospital. PATIENTS: Forty-five CL/P children (mean age of 8.8 years) and 45 age-matched, gender-matched, and postal code-matched noncleft patients. MAIN OUTCOME MEASURES: The overall percentage of missed appointments at three different clinics by CL/P patients and the difference in attendance rates at the pediatric dentistry clinic between CL/P and non-CL/P children. RESULTS: Pediatric dentistry had the highest rate of missed appointments (22.4%), followed by the multidisciplinary cleft clinic (9.2%) and the orthodontic clinic (8.8%). CL/P patients missed a significantly greater proportion of their pediatric dentistry appointments than noncleft children (22.4% versus 11.9%). Patients with a bilateral CL/P were significantly more likely to miss an appointment than patients with a unilateral CL/P. Age, gender, medical history, and distance traveled had no significant effect on attendance rates. CONCLUSIONS: Further work is needed to identify risk factors for poor attendance and to develop strategies to reduce the frequency of missed appointments in this vulnerable group. 相似文献
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Oral ulcerations associated with HIV infection include recurrent aphthous ulcers (RAU). Whereas RAU prevalence is not increased, lesion severity is: among a group of HIV+ patients, 66% had the more severe herpetiform or major RAU. This increased severity suggests that HIV disease-related changes in the immune system may exacerbate RAU. In the peripheral blood of healthy subjects with RAU, CD4:CD8 cell ratios may be reversed and the proportion of T cell receptor-γδ+ cells increased. HIV disease-related immune system changes are characterized by reversed CD4:CD8, lowered CD4 cell counts and an inverse correlation between CD4 cell counts and per cent activated γδ lymphocytes. Adhesion molecules and cytokines involved in lymphocyte homing may be important in RAU pathogenesis: ICAM-I and ELAM are strongly expressed, and TNFα production is increased in peripheral blood lymphocytes of healthy patients with RAU. In patients with active HIV disease/AIDS, serum TNFα levels are increased. Thalidomide, which inhibits TNFα production, is effective treatment for RAU. Some RAU patients have vitamin B12 or folate deficiencies, levels of which are commonly low in HIV+/AIDS patients. However, in a case control study of HIV+ patients, vitamin B12- or folate-deficiencies were not found to be significant risk factors for RAU. 相似文献
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