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71.
Purpose:To analyze the reasons for delay in cataract surgery in patients with advanced cataracts during the COVID-19 pandemic.Methods:This was a prospective, cross-sectional, multicenter questionnaire study which included patients with mature cataract, nuclear sclerotic cataract grade IV, and cataracts with best corrected visual acuity (BCVA) <5/60, during the COVID-19 pandemic from December 2020 to April 2021. Reasons for delay in presentation to the hospital were analyzed.Results:One thousand four hundred seventy two patients were recruited with advanced cataracts. Absence of ophthalmic care nearby (44.2%), lack of awareness regarding elective surgeries (42.6%), lack of public transportation (37%), fear of contracting COVID-19 (23.4%), and waiting for outreach camps (20.4%) were found to be the reasons behind the delay in cataract surgery. 53.7% of the patients had worsening of defective vision and 55.3% of them had difficulty in carrying out activities of family living. 30.8% of the patients faced difficulty in commuting and 8.4% of the patients suffered a fall during this pandemic due to worsening of the visual acuity.Conclusion:The lockdown imposed during the pandemic has created a significant backlog of patients who are progressing to advanced cataracts due to lack of ophthalmic care nearby, lack of awareness regarding elective surgeries, lack of public transportation, and no outreach camps. Proactive measures to deal with this backlog are of utmost need to prevent blindness due to cataract.  相似文献   
72.
目的探讨胃镜、B超、CT在进展期胃癌诊断、治疗中的应用价值。方法回顾性分析112例经手术及病理证实的进展期胃癌的胃镜、B超、CT资料。结果112例进展期胃癌,胃镜符合率为100%(112/112),B超符合率96.4%(108/112),CT符合率98.2%(110/112);恶性肿瘤TNM分期:B超符合率78.6%(88/112),CT符合率83.0%(93/112)。结论胃镜检查结合黏膜活检仍然是进展期胃癌首选检查手段,B超、CT检查可对胃癌进行术前TNM分期,三者合理应用能更好地提高进展期胃癌的诊断、指导临床治疗、术后疗效观察及预后判断水平。  相似文献   
73.
目的研究颈部肿块性质与年龄和性别的关系,以期提高颈部肿块的诊断水平。方法回顾性分析2000年1月至2006年1月经病理确诊颈部肿块病例2136例。根据肿块的性质分为先天性、良性、恶性肿块。按年龄段分为四组:0~19岁,20~39岁,40~59岁,≥60岁。统计各年龄组三种性质肿块的构成比及不同年龄组、不同性别三种性质肿块的构成比。结果三种性质肿块在不同年龄组构成比均差异有统计学意义(P<0.01)。先天性肿块多见于20岁以下,各年龄组男女无差异;良性肿块多见于20~39岁,男女构成比差异有统计学意义(P<0.05),女性多于男性,其余三组中男女无差异(P>0.05);恶性肿块多见于40岁以上,男女构成比相比在0~19岁差异无统计学意义(P>0.05),在其余三组差异有统计学意义(P<0.01),男性多于女性。结论颈部肿块性质与年龄和性别存在着明显的关系,年龄和性别对颈部肿块的诊断有很大的帮助,临床上诊断颈部肿块时应考虑年龄和性别的因素。  相似文献   
74.
Increasing evidence shows the nasal epithelium to be the initial site of SARS-CoV-2 infection, and that early and effective immune responses in the upper respiratory tract (URT) limit and eliminate the infection in the URT, thereby preventing infection of the lower respiratory tract and the development of severe COVID-19. SARS-CoV-2 interferes with innate immunity signaling and evolves mutants that can reduce antibody-mediated immunity in the URT. Recent genetic and immunological advances in understanding innate immunity to SARS-CoV-2 in the URT, and the ability of prior infections as well as currently available injectable and potential intranasal COVID-19 vaccines to generate anamnestic adaptive immunity in the URT, are reviewed. It is suggested that the more detailed investigation of URT immune responses to all types of COVID-19 vaccines, and the development of safe and effective COVID-19 vaccines for intranasal administration, are important needs.  相似文献   
75.
76.
For the Honghe Bridge project located in Yunnan Province, Southwest China, a steel/ultrahigh-performance concrete (UHPC) composite deck is used in the suspension bridge with a 700 m main span, and the steel stud connectors are used in the 50 mm–thick UHPC layer. To investigate the shrinkage behavior of UHPC and the relevant influence, the in situ time-dependent strain is measured continuously, and within the 20-day curing time, the material behavior is summarized based on test results. This paper proposes a prediction model for UHPC shrinkage which is refined from the widely used B3 model for normal concrete material, and the parameter values are modified and optimized by experimental comparison. Combining the numerical model and the finite element analysis model of the composite deck, the detailed mechanical state in structural parts is studied. For the practical construction, the simulation results indicate that the small thickness of UHPC above the stud and weak bond strength can influence the eventual structural performance greatly. In the discussion of stress distribution at different locations of the deck, the potential crack on the edge and the corner of the UHPC–steel interface and the mechanical damage on the stud connector around are also indicated.  相似文献   
77.
78.
To assess the most influential factor for pupil diameter changes among age, illuminance, and refractive state and reestablish the optimal procedures for clinical applications based on refractive state and illuminance for different age groups.The study was an observational study (repeated measure study). Participants included 219 Korean adults aged 20 to 69 years. Pupil diameters were measured using a pupilometer under scotopic, mesopic-low, and mesopic-high lighting conditions. Factor interactions among age, illuminance, and refractive state were evaluated using mixed linear model and chi-square automated interaction detection.Illuminance mainly contributed to variations in pupil diameter of participants over 50 years, whereas the refractive state was the dominant controlling factor for the pupil variation in participants below 50 years. For more generalized application, the pupil diameter decreased with older age and brighter illuminance (P < .001, inverse correlation, all comparisons). The mean pupil diameter was significantly higher in myopes and emmetropes than in hyperopes (P < .001). Pupil diameter variation modeled using the mixed model confirmed age, illuminance, and refractive error as significant factors (P < .001).Accounting for the interactions among age, illuminance, and refractive error and establishing their hierarchical dominance can be generalized using the chi-square automated interaction detection method and mixed model. Promoting age-dependent consideration for both illuminance and refractive state is necessary when pupil diameters play significant roles in clinical and manufacturing circumstances.  相似文献   
79.
PurposeSarcopenia is a major health problem in community-dwelling elderly individuals. Hypertension is postulated to aggravate sarcopenia. The present study was performed to estimate the prevalence of and factors associated with sarcopenia among elderly individuals with hypertension.MethodsThis study involved 165 Chinese individuals with hypertension aged ≥60 years who were evaluated for sarcopenia using the Asian Working Group for Sarcopenia criteria. Data on their sociodemographic information, physical illnesses, and clinical and functional status were collected.ResultsThe overall prevalence of sarcopenia among elderly individuals with hypertension was 20.2%. The factors significantly associated with sarcopenia were an age of ≥70 years (adjusted odds ratio (OR), 3.01; 95% confidence interval (CI), 1.17–5.39), diabetes (OR, 4.45; 95% CI, 1.32–11.16), osteoporosis (OR, 2.52; 95% CI, 1.13–5.37), drinking (OR, 3.28; 95% CI, 1.26–7.85), and a body mass index of 24.0 to 27.9 kg/m2 (OR, 0.74; 95% CI, 0.59–0.91).ConclusionsThis study revealed a very high prevalence of sarcopenia among elderly individuals with hypertension (20.2%). Sarcopenia may be associated with advanced age, drinking, diabetes, the body mass index, and osteoporosis. The longitudinal relationship between clinic visits and sarcopenia should be further evaluated.  相似文献   
80.
芳香化酶抑制剂来曲唑的研究进展   总被引:3,自引:0,他引:3  
来曲唑是新一代强效的非甾体芳香化酶抑制剂,用于一线治疗晚期乳腺癌,并广泛用作乳腺癌的二线用药.疗效好,不良反应少,耐受性好.值得临床推广应用。本文综述了来曲唑的合成方法以及临床研究进展。  相似文献   
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