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71.
目的 研究慢性心房颤动(房颤)犬心房能量代谢的变化,探讨曲美他嗪对房颤能量代谢和内皮功能的影响.方法 18只健康杂种犬,随机分为窦性心律组、心房起搏组和曲美他嗪组,每组6只犬.心房起搏组以400次/min快速起搏心房6周,建立房颤犬动物模型;曲美他嗪组给予曲美他嗪5 mg·kg-1·d-1口服,随后以400次/min快速起搏心房6周.采用高效液相色谱测定心肌组织磷酸肌酸(CrP)、三磷酸腺苷(ATP)、二磷酸腺苷(ADP)和一磷酸腺苷(AMP)含量,计算总腺苷酸池(TAN);用Western blot定量、免疫组化定性检测左房内皮型一氧化氮合酶(eNOS)蛋白表达,酶联免疫吸附定量检测血浆血管性血友病因子(vWF)含量,采用硝酸还原酶法测定血浆NO2-/NO3-(NOx)含量.结果 与窦性心律组相比,心房起搏6周后,心房肌CrP(P<0.01)和CrP/ATP(P<0.05)显著降低,而ATP、ADP、AMP和TAN无明显变化(P>0.05),内皮细胞功能标志物血浆vWF明显增高,NOx降低,心房eNOS蛋白表达减少.曲美他嗪治疗6周,心房肌CrP、CrP/ATP、ATP、ADP、AMP和TAN差异均无统计学意义,但eNOS蛋白表达上调(P<0.05),血浆vWF含量降低(P<0.01),NOx增加(P<0.05),内皮细胞功能改善.结论 房颤早期可出现能量代谢失衡,但随着持续时间延长,能量供求能重新达到平衡.曲美他嗪对房颤能量代谢无明显影响,但能通过一氧化氮途径改善内皮细胞功能.  相似文献   
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Objective

To examine the multidimensional concept of patient-health care provider (HCP) communication, its effects on patient satisfaction with oncology care services, and related racial differences.

Methods

The current analysis draws from a population-based survey sample of 1011 African American and 1034 Caucasian American men with newly diagnosed prostate cancer. The variables of satisfaction with health care services, interpersonal treatment, contextual knowledge of the patient, and prostate cancer communication were analyzed using multiple-group structural equation modeling.

Results

Regardless of race, patient-HCP communication was related positively to interpersonal treatment by the HCP, HCP's contextual knowledge of the patient, and prostate cancer communication. More positive patient-HCP communication was related to more satisfaction with health care services. Racial differences were significant in the relationships between patient-HCP communication and prostate cancer communication.

Conclusion

Content and interpersonal relationships are important aspects of patient-HCP communication and affect patient satisfaction with oncologic care for prostate cancer.

Practice implications

HCPs need to integrate the transfer of information with emotional support and interpersonal connection when they communicate with men with newly diagnosed prostate cancer.  相似文献   
75.
Minority groups continue to suffer disproportionately from COVID-19's impact, with Blacks and Hispanics three times more likely to die from the disease than their White counterparts. The COVID-19 vaccine roll out has the potential to provide relief to these most adversely impacted communities. However, historic mistrust within racial minority communities threatens to derail the effective implementation of a vaccination program. The origin of this mistrust is multifactorial. Current day experience with structural racism and research abuses like Tuskegee Study collectively influence our perception of biased healthcare system. We outline issues and propose solutions that must be addressed to achieve a successful vaccination agenda. Mishandling of public expectations at any point may lead to an avalanche of vaccine opposition which might be unrecoverable.  相似文献   
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ObjectiveTo describe and compare how obstetric patients and care providers view preterm birth risk assessment and communication.MethodsWe conducted eight focus groups with obstetric patients (n = 35) and 16 qualitative interviews with obstetric providers. Grounded theory was used to identify and analyze themes.ResultsPatients' knowledge about preterm birth varied greatly. Similar benefits and risks of preterm birth risk counseling were discussed by patients and providers with notable exceptions: patients cited preparedness as a benefit and providers cited maternal blame, patient alienation, and estimate uncertainty as potential risks. Most patients expressed a desire to know their personalized preterm birth risk during pregnancy. Providers differed in whether they offer universal versus selective, and quantitative versus qualitative, preterm birth risk counseling. Many providers expressed concern about discussing social and structural risk factors for preterm birth.ConclusionWhile many patients desired knowing their personalized preterm birth risk, prenatal care providers’ disclosure practices vary because of uncertainty of estimates, concerns about negative consequences and challenges of addressing systemic inequities and social determinants of health.Practice implicationsGiven the existing asymmetry of information about preterm birth risk, providers should consider patient preferences regarding and potential benefits and risks of such disclosure in their practice.  相似文献   
78.
《Dental materials》2020,36(4):535-541
ObjectiveTo evaluate the cyclic contact fatigue resistance and failure mode of ceramics for monolithic and multilayer restorations.MethodsCeramic structures (10 mm × 1.8 mm) were fabricated as follows (n = 28): (1) CAD-on- trilayer structure composed of Y-TZP (yttria stabilized tetragonal zirconia polycrystal- IPS e.max ZirCAD) infrastructure, fusion glass–ceramic (IPS e.max CAD Crystall/Connect) and lithium disilicate-based glass–ceramic (IPS e.max CAD); (2) ZFC- bilayer structure composed of Y-TZP infrastructure veneered by a fluorapatite glass–ceramic (IPS e.max Ceram); (3) LDC- monolithic lithium-disilicate glass–ceramic (IPS e.max CAD); and (4) YZW- monolithic Y-TZP (Zenostar Zr Translucent). All ceramics structures were bonded to a dentin analog substrate (G10). Specimens were submitted to cyclic contact fatigue test in a pneumatic cycling machine with 80 N load and 2 Hz frequency in distilled water at 37 °C. Test was interrupted after 104, 105, 5 × 105 and 106 cycles and the presence or absence of failure was recorded. Fatigue data were analyzed using Kaplan–Meier (log rank) and Holm–Sidak tests (α = 0.05). The relationship between the type of crack leading to failure and the experimental group was analyzed using chi-square test (α = 0.05).ResultsThere was no statistical difference between CAD-on and YZW groups (p = 0.516), which presented the highest survival rates after cyclic loading, followed by ZFC and LDC groups (p < 0.01). There was a significant relationship between type of crack and experimental group (p < 0.001). LDC specimens showed the greatest frequency of radial cracks, while cone cracks were more prevalent for ZFC and CAD-on specimens.SignificanceMonolithic Y-TZP (YZW) showed similar fatigue resistance to CAD-on multilayer specimens, but different failure mode. Monolithic lithium disilicate glass–ceramic (LDC) and Y-TZP conventionally veneered by glass–ceramic (ZFC) showed lower survival time under fatigue.  相似文献   
79.
相对传统新药研发模式,药物重定位策略发现药物新用途具有显著的成本效益优势,能加快药物上市步伐,满足恶性肿瘤、罕见病、个性化医疗等特定领域药物临床用药需求,因而被各界关注。本文主要介绍了药物重定位的一般流程与候选药物筛选路径,如从非理性设计方法向基于相似性、基于结构虚拟筛选、推理与机器学习等理性设计方法发现重定位药物的系统性转变。  相似文献   
80.
One new triterpenoid, 3β-[(E)-caffeoyloxy]-D:C-friedooleana-7,9(11)-dien-29-oic acid (1) and nine known triterpenoidsidentified as cucurbitacin B (2), 23,24-dihydrocucurbitacin B (3), 23,24-dihydrocu-curbitacin D (4), cucurbitacin D (5), cucurbalsaminol A (6), 3-epi-isocucurbitacin D (7), curbitacin G (8), cucurbitacin J (9) and cucurbitacin I (10)were purified from Trichosanthes cucumeroides. Their structures were confirmed by spectroscopic data analysis and comparison with previous literature. All compounds were obtained from T.cucumeroides for the first time.  相似文献   
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