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91.
斜视手术2100例回顾分析   总被引:7,自引:7,他引:0  
目的:探讨斜视的诊断和手术治疗技巧。方法:回顾分析2100例斜视的临床特点及手术治疗,包括性别、年龄、临床特征、就诊季节、弱视治疗、手术时机、手术方式的选择和手术并发症等。结果:2100例斜视纳入研究(其中男1105例,女995例);各年龄段分别为:<10岁,684例(32.57%);11~20岁,895例(42.62%);21~40岁,432例(20.57%);>40岁,89例(4.24%);其中共同性内斜视882例(42.00%)、共同性外斜视845例(40.23%),非共同性内斜视172例(8.19%),非共同性外斜视130例(6.19%),先天性眼球震颤45例(2.14%),A-V征26例(1.24%)。共同性斜视早期采取水平直肌加强和减弱术,使患者建立同时视觉和治疗弱视;眼球震颤患者头位<30°的采用Parks法矫正,头位>30°者手术量增加40%~60%;A-V征斜视应针对病因,合理正确选择斜肌或直肌肌腱移位术式;急性眼外肌麻痹的病因诊断非常重要,Jensen联结术是有效的手术方式。结论:斜视和弱视并存的手术时机非常重要。复杂性斜视手术的成功率取决于术前的正确诊断、手术方案的制定、手术量的设计和术中的经验判断。  相似文献   
92.

Background

It has been reported that particulate matter (PM) is associated with cardiovascular diseases (CVD) while metabolic syndrome is also an important risk factor for CVD. However, few studies have investigated the epidemiological association between PM and metabolic syndrome.

Objective

To investigate the association between one-year exposure to PM with an aerodynamic diameter <2.5?μm (PM2.5) and the risk of metabolic syndrome in Korean adults without CVD.

Methods

Exposure to PM2.5 was assessed using a Community Multiscale Air Quality (CMAQ) model. Metabolic syndrome was defined by National Cholesterol Education Program Adult Treatment Panel III. Andersen and Gill model with time-varying covariates, considering recurrent events, was used to investigate the association between one-year average PM2.5 and the risk of incident metabolic syndrome in 119,998 adults from the national health screening cohort provided by Korea National Health Insurance from 2009 to 2013.

Results

Higher risk of metabolic syndrome, waist-based obesity, hypertension, hypertriglyceridemia, low HDL cholesterol, and hyperglycemia were significantly associated with a 10-μg/m3 increase in PM2.5 [adjusted hazard ratio (HR): 1.070, 1.510, 1.499, 1.468, 1.627 and 1.380, respectively]. In addition, the risk of metabolic syndrome associated with PM2.5 exposure was significant in the consistently obese group (obese at baseline and endpoint).

Conclusion

Exposure to one-year average PM2.5 is associated with an increased risk of metabolic syndrome and its components in adults without CVD. These associations are particularly prominent in the consistently obese group (obese at baseline and endpoint). Our findings indicate that PM2.5 affects the onset of MS and its components which may lead to increase the risk of CVD.  相似文献   
93.
94.
The functional support and advancement of our body while preserving inherent naturalness is one of the ultimate goals of bioengineering. Skin protection against infectious pathogens is an application that requires common and long-term wear without discomfort or distortion of the skin functions. However, no antimicrobial method has been introduced to prevent cross-infection while preserving intrinsic skin conditions. Here, we propose an antimicrobial skin protection platform copper nanomesh, which prevents cross-infectionmorphology, temperature change rate, and skin humidity. Copper nanomesh exhibited an inactivation rate of 99.99% for Escherichia coli bacteria and influenza virus A within 1 and 10 min, respectively. The thin and porous nanomesh allows for conformal coating on the fingertips, without significant interference with the rate of skin temperature change and humidity. Efficient cross-infection prevention and thermal transfer of copper nanomesh were demonstrated using direct on-hand experiments.

The functional support and advancement of our body while preserving the inherent naturalness is one of the ultimate goals of bioengineering (14). A functional layer is placed on the skin to complement the intrinsic biological and interactive functions (5, 6) and to add functions that do not yet exist (79). During use, the second skin layer should completely exploit its function and underlay skin functions without deforming the skin or interfering with the skin’s external interaction. Materials and structures need to be conformal and mechanically similar to the skin to minimize the distortion of natural sensations and movements. In addition, the air and heat transfer on the skin must be unimpeded to obtain a natural and comfortable wear fit (10).Body protection that requires common and long-term wear is an application in which both functionality and naturalness are important. As the outermost layer connecting our body to the environment, the skin is exposed to physical damage, hazardous chemicals, and infectious pathogens (11, 12). Therefore, we add a protective layer on the skin that blocks or filters out external contaminants. This entails the isolation and accumulation of biochemical compounds, which can lead to self-contamination and the subsequent cross-contamination/infection by interacting with other objects. In contrast to chemical contamination, which is not self-reproductive, the biological contamination of infectious microbes, such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a considerable issue to be addressed.By containing an antimicrobial material on the surface of the skin protective layer, cross-infection can be prevented in the long term. Unlike temporary rinsing or disinfection, the use of antibacterial or antiviral substances such as chemical or natural disinfectants and metal nanomaterials inhibits the growth of microorganisms on the surface (1317). These materials are embedded in a complete covering polymer layer, such as gloves (18, 19), to isolate and protect both the inner and outer surfaces from the infection. To add breathability to the textile especially for the mask (13, 20, 21), many antibacterial fibers have been developed based on these materials. Moreover, various skin-attachable platforms with antimicrobial properties have been developed for convenient usage in daily lives. Antimicrobial nanofibers with conformal attachment to the skin have been developed for drug delivery, wound healing (22, 23), and electrophysiology (24, 25). In addition, stretchable and antibacterial hydrogels have been developed to allow more natural skin movement in wound-healing applications (2628).However, there has been no practical skin protective solution to prevent cross-infection while preserving intrinsic skin conditions such as surface morphology, thermal transfer, and skin humidity. The thickening of the additional skin layer frequently results in a significant modification of the surface morphology, heat transfer, and the corresponding sensation. Thin layers have limited performance in terms of antimicrobial duration and speed. The skin coverage of polymer or hydrogel film blocks the transfer of air, moisture, and heat. In addition, the antimicrobial performance is focused on the skin side rather than the external side that affects cross-infection. Voids owing to the stiffness of the film or fiber and morphological differences compared to the skin further limit conformality, heat transfer, and water/air permeability (29).Here, we propose an antimicrobial skin protection platform copper nanomesh, which prevents cross-infection while minimizing modification of intrinsic skin properties such as interfacial morphology, temperature change rate, and skin humidity. The thin thickness and porous structure of the nanomesh allow conformal attachment to the fingertips, regardless of the mechanical and structural variations of the fingerprints, nails, and interfaces. To impart antimicrobial properties, copper, one of the most well-known antimicrobial (nano)materials (3033), was coated with maintaining the nanomesh structure (copper nanomesh, from here onward). The measured inactivation rates of copper nanomesh against Escherichia coli bacteria and influenza virus A (H1N1) were 99.99% within 1 min and 10 min, respectively. It was found that the nanomesh structure contributed to the acceleration of bacterial inactivation compared to the copper film. Furthermore, it exhibited high biocompatibility with the skin cells and stable antibacterial performance even after long-term use (more than 6 h), including water immersion (more than 1 h).In addition, we investigated the naturalness of the copper nanomesh compared to that of the copper film and conventional gloves. As confirmed using the artificial skin and fingerprint recognition, the proposed copper nanomesh exhibited a higher conformability compared to that of the copper film. The copper nanomesh showed a high hydrophobicity to block external contaminants in solution while having high gas permeability and maintaining the skin humidity in a safe range. Additionally, the insertion of copper nanomesh did not affect the temperature change rate, which is important to maintain the sensation and comfort fit of the skin. Finally, the copper nanomesh was compared to the glove by wearing on our hands and interacting with various real-life objects. Using the proposed copper nanomesh, we successfully achieved an effective prevention of cross-infection and less-hindered thermal recognition of objects.  相似文献   
95.
To investigate the adverse effects of clozapine on cardiovascular ion channels, we examined the inhibitory effect of clozapine on voltage-dependent K+ (Kv) channels in rabbit coronary arterial smooth muscle cells. Clozapine-induced inhibition of Kv channels occurred in a concentration-dependent manner with an half-inhibitory concentration value of 7.84 ± 4.86 µM and a Hill coefficient of 0.47 ± 0.06. Clozapine did not shift the steady-state activation or inactivation curves, suggesting that it inhibited Kv channels regardless of gating properties. Application of train pulses (1 and 2 Hz) progressively augmented the clozapine-induced inhibition of Kv channels in the presence of the drug. Furthermore, the recovery time constant from inactivation was increased in the presence of clozapine, suggesting that clozapine-induced inhibition of Kv channels is use (state)-dependent. Pretreatment of a Kv1.5 subtype inhibitor decreased the Kv current amplitudes, but additional application of clozapine did not further inhibit the Kv current. Pretreatment with Kv2.1 or Kv7 subtype inhibitors partially blocked the inhibitory effect of clozapine. Based on these results, we conclude that clozapine inhibits arterial Kv channels in a concentration- and use (state)-dependent manner. Kv1.5 is the major subtype involved in clozapine-induced inhibition of Kv channels, and Kv2.1 and Kv7 subtypes are partially involved.  相似文献   
96.
97.
BackgroundAsthma and chronic obstructive pulmonary disease (COPD) are airway diseases with similar clinical manifestations, despite differences in pathophysiology. Asthma-COPD overlap (ACO) is a condition characterized by overlapping clinical features of both diseases. There have been few reports regarding the prevalence of ACO in COPD and severe asthma cohorts. ACO is heterogeneous; patients can be classified on the basis of phenotype differences. This study was performed to analyze the prevalence of ACO in COPD and severe asthma cohorts. In addition, this study compared baseline characteristics among ACO patients according to phenotype.MethodsPatients with COPD were prospectively enrolled into the Korean COPD subgroup study (KOCOSS) cohort. Patients with severe asthma were prospectively enrolled into the Korean Severe Asthma Registry (KoSAR). ACO was defined in accordance with the updated Spanish criteria. In the COPD cohort, ACO was defined as bronchodilator response (BDR) ≥ 15% and ≥ 400 mL from baseline or blood eosinophil count (BEC) ≥ 300 cells/μL. In the severe asthma cohort, ACO was defined as age ≥ 35 years, smoking ≥ 10 pack-years, and post-bronchodilator forced expiratory volume in 1 s/forced vital capacity < 0.7. Patients with ACO were divided into four groups according to smoking history (threshold: 20 pack-years) and BEC (threshold: 300 cells/μL).ResultsThe prevalence of ACO significantly differed between the COPD and severe asthma cohorts (19.8% [365/1,839] vs. 12.5% [104/832], respectively; P < 0.001). The percentage of patients in each group was as follows: group A (light smoker with high BEC) – 9.1%; group B (light smoker with low BEC) – 3.7%; group C (moderate to heavy smoker with high BEC) – 73.8%; and group D (moderate to heavy smoker with low BEC) – 13.4%. Moderate to heavy smoker with high BEC group was oldest, and showed weak BDR response. Age, sex, BDR, comorbidities, and medications significantly differed among the four groups.ConclusionThe prevalence of ACO differed between COPD and severe asthma cohorts. ACO patients can be classified into four phenotype groups, such that each phenotype exhibits distinct characteristics.  相似文献   
98.
目的:探讨在高原服用富氧水对移居青年心肺功能的影响。方法:对进驻海拔3700m1年的10名青年在服用富氧水前和服用富氧水(每次500mL,一日2次)15天后分别用EGM-II型踏车功量计做坐位踏车运动,初始负荷功率为50W,每3min递增50W,以60r/min连续踏车至200W,3min后终止。用直线回归法计算每位受试者功率200W时的心率(HR)及血氧饱和度(SaO2),记录运动终止5min后恢复HR,按公式计算心功能指数。结果:服用富氧水15天后,心功能指数增高,功率200W时SaO2增高;功率200W时的HR和运动终止5min恢复HR降低,差别有非常显著性意义(P〈0.01)。结论:服用富氧水能提高高原移居青年的心肺功能。  相似文献   
99.
OBJECTIVE. The objective of this study was to compare the value of color Doppler sonography with early clinical and laboratory findings in determining the prognosis of patients with ischemic colitis. SUBJECTS AND METHODS. We reviewed the early clinical, laboratory, and color Doppler sonographic data of 24 patients with ischemic colitis. The patients were divided into two groups on the basis of their outcome. The first group comprised the patients with transient ischemia who recovered uneventfully, and the second group included the patients who needed surgery because of symptomatic transmural colic gangrene or colic stricture. Clinical data and laboratory values were compared with color Doppler sonographic findings including colic wall thickness, presence of stratification, and arterial flow in the bowel wall. RESULTS. At univariate analysis, increased age (p = 0.007), leukocyte count (p = 0.030), lactate dehydrogenase level (p = 0.030), blood lactate level (p = 0.041), and absence of vascular flow in the colic wall (p<0.001) were significantly related to complicated ischemic colitis. At multivariate analysis, absence of arterial flow was the only significant predictor of complicated ischemic colitis (p = 0.002), with a sensitivity of 82%, a specificity of 92%, a positive predictive value of 90%, and a negative predictive value of 86%. CONCLUSION. Absence of arterial flow in the wall of the ischemic colon on initial color Doppler sonography is suggestive of an unfavorable outcome and is more closely associated with outcome than early clinical and laboratory findings.  相似文献   
100.
一种新的T细胞相关分子IBP表达水平定量检测方法的建立   总被引:1,自引:0,他引:1  
目的 建立一种定量检测IBP表达水平的方法 ,为研究IBP在免疫细胞分化以及在免疫性疾病当中的作用奠定基础.方法 利用反转录PCR和PCR技术获得目的 基因和内参基因片段,构建重组质粒,以重组质粒为标准品,建立实时PCR标准曲线;测定外周血白细胞IBP和β-actin表达水平.以β-actin为内参照,均一化检测结果 .结果 重组质粒的阳性克隆经PCR扩增,0.8%琼脂糖凝胶电泳鉴定,目的 基因片段插入载体内;建立起实时PCR标准曲线.检测20例正常人全血标本,得到比较稳定的检测结果 .结论 成功建立了用实时PCR定量检测IBP mRNA表达水平方法 ,为进一步研究IBP奠定了基础.  相似文献   
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