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11.
Here 15 cases of advanced Juvenile angiofibroma are presented. Advantages of wide tumour exposure and preoperative embolization are discussed.  相似文献   
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Survival rates of patients with either early and advanced stage non–small-cell lung cancer (NSCLC) have improved with newer systemic therapy and radiation techniques, including combination regimens, targeted therapies, and immunotherapies. The cancer cooperative groups have historically played a critical role in the advancement of NSCLC therapy. Annually, representatives from cooperative groups worldwide convene at the International Lung Cancer Congress (ILCC). In summer 2015, the ILCC reached its 16th anniversary. This article highlights the NSCLC studies presented by participating groups in 2015.  相似文献   
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Purpose:Anemia is common in adolescent girls. Apprehension while drawing blood to estimate hemoglobin concentration is a barrier for confirming anemia. ToucHb, a noninvasive instrument that estimates the hemoglobin by taking an image of the exposed conjunctiva, was used during eye screening to help diagnose and treat anemia.Methods:ToucHb was used during secondary school eye screening and during house-to-house eye screening to estimate the hemoglobin concentration in the body. Each of the girls was distributed a packet of 60 tablets of ferrous and folate and a tablet of albendazole. They were followed up after 3 months.Results:Exactly 1511 municipal school girls aged 10-19 years (mean 12.9; standard deviation [SD] 1.64) were examined. Of them, 949 (62.8%) had hemoglobin of ≤9 mg%. Among those girls with hemoglobin ≤9 mg%, the mean (SD) during the initial and follow-up examinations was 6.1 (1.4) and 9.6 (1.03), respectively, by paired t-test (P < 0.001). Another 588 girls (average age 14.4 years, SD 1.2) had their eyes examined and hemoglobin estimated during a house-to-house eye screening. Of them, 116 (19.7%) had hemoglobin level of ≤9 mg%. Their pre-Hb was 7.9 (SD 1.05) on average and after 3 months, it was 9.6 (SD 1.02). Among those girls with hemoglobin ≤9 mg%, the mean (SD) during the initial and follow-up examinations was 6.2 (1.4) and 7.9 (1.1), respectively, by paired t-test (P < 0.001)Conclusion:ToucHb was useful to diagnose anemia while doing eye screening and to ensure its treatment. Anemia diagnosis and management would enhance the health of adolescent girls.  相似文献   
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India has set aggressive targets to install more than 400 GW of wind and solar electricity generation by 2030, with more than two-thirds of that capacity coming from solar. This paper examines the electricity and carbon mitigation costs to reliably operate India’s grid in 2030 for a variety of wind and solar targets (200 GW to 600 GW) and the most promising options for reducing these costs. We find that systems where solar photovoltaic comprises only 25 to 50% of the total renewable target have the lowest carbon mitigation costs in most scenarios. This result invites a reexamination of India’s proposed solar-majority targets. We also find that, compared to other regions and contrary to prevailing assumptions, meeting high renewable targets will avoid building very few new fossil fuel (coal and natural gas) power plants because of India’s specific weather patterns and need to meet peak electricity demand. However, building 600 GW of renewable capacity, with the majority being wind plants, reduces how often fossil fuel power plants run, and this amount of capacity can hold India’s 2030 emissions below 2018 levels for less than the social cost of carbon. With likely wind and solar cost declines and increases in coal energy costs, balanced or wind-majority high renewable energy systems (600 GW or 45% share by energy) could result in electricity costs similar to a fossil fuel-dominated system. As an alternative strategy for meeting peak electricity demand, battery storage can avert the need for new fossil fuel capacity but is cost effective only at low capital costs ( USD 150 per kWh).

India emitted 3.2 billion metric tons of CO2e in 2016, or 6% of annual global greenhouse gas emissions, placing it third only to China and the United States (1). One-third of these emissions were from coal-based electricity. At the same time, both per capita emissions and energy use remain well below global averages, suggesting a massive potential for growth of electricity generation and emissions (1). India’s primary energy demand is expected to double by 2040 compared to 2017 (2). Whether this energy comes from fossil or low-carbon sources will significantly affect the ability to limit average global temperature rise to below 2 °C.India is already pursuing significant technology-specific renewable energy targets—100 GW of solar and 60 GW of wind by 2022—and, in its Nationally Determined Contributions (NDC), committed to a 40% target for installed generation capacity from nonfossil fuel sources by 2030 (3). In 2019, in part to fulfill its NDC commitment, the Indian government proposed to install 440 GW of renewable energy capacity by 2030, with 300 GW of solar and 140 GW of wind capacity (4). Although costs of solar photovoltaic (PV) and wind technologies have declined significantly in recent years (57), the low cost of coal and integration costs associated with variable renewable energy (VRE) technologies like wind and solar may hinder India’s cost-effective transition to a decarbonized electricity system. This paper seeks to answer a number of questions that arise in the Indian context. What targets for wind and solar capacity have the lowest associated integration costs? Will these targets significantly offset the need to build fossil fuel generation capacity? What additional measures can we take to mitigate VRE integration costs?Merely comparing the levelized costs of VRE with the costs of conventional generation ignores additional cost drivers, which depend on the timing of VRE production and other conditions in the power system (8, 9). Quantifying these drivers requires models that choose lowest-cost generation capacity portfolios and simulate optimal system operation with detailed spatiotemporal data. Several prior studies address these system-level integration costs in a capacity expansion planning framework (1016), often making decisions based on a limited sample of representative hours. Other studies explicitly estimate the relationship between long-run economic value (including integration costs) of VRE penetration levels (17, 18) but do not include VRE investment costs in their analysis. Few prior studies explore the impacts of high VRE penetration on India’s electricity system, and those that do either use the capacity expansion framework and do not evaluate the economic value of multiple VRE targets (4, 19, 20) or do not optimize capacity build around proposed VRE targets (21).Here we address this gap by estimating how different VRE targets affect the cost to reliably operate the Indian electricity system. To do so, we work with three interrelated models. First, using a spatially explicit model for VRE site selection, we identify the lowest levelized cost wind and solar sites to meet different VRE capacity targets, and study how the resource quality—and corresponding levelized cost—of selected sites changes with increasing VRE targets.Second, using a capacity investment model that accounts for VRE production patterns and optimal dispatch of hydropower and battery storage, we determine the capacity requirements and investment costs for coal, combined cycle gas turbines (CCGT), and combustion turbine (CT) peaker plants. Due to uncertainties in their future deployment (22), and because their current targets are relatively low (4), we did not consider new nuclear or hydro capacity in the main scenarios but include those in the sensitivity scenarios presented in SI Appendix, section 2. Third, we use a unit commitment and economic dispatch model to simulate hourly operation of the electricity system and estimate annual system operational costs. This model captures important technical constraints, including minimum operating levels, daily unit commitment for coal and natural gas plants, and energy limits on hydropower and battery storage. Rather than cooptimize VRE capacity, we compute the system-level economic value of a range of VRE targets by comparing the sum of the avoided new conventional capacity and energy generation costs to a no-VRE scenario. The net cost for a scenario is then the difference between the levelized cost of the VRE and the system-level economic value. Materials and Methods provides more detail on this process.Our results show that, despite greater levelized cost reduction forecasts for solar PV compared to wind technologies, VRE targets with greater amounts of wind have the lowest projected net carbon mitigation costs. This finding is robust to a range of scenarios, including low-cost solar and storage, and lower minimum generation levels for coal generators.We find that, although VRE production displaces energy production from conventional generators, it does very little to defer the need for capacity from those generators due to low correlation between VRE production and peak demand. Our findings suggest that VRE in India avoids far less conventional capacity than VRE in other regions in the world. These capacity requirements are slightly mitigated if India’s demand patterns evolve to more closely resemble demand in its major cities. Overall, we conclude that the importance of choosing the right VRE mix is significant when measured in terms of carbon mitigation costs: Whereas most solar-majority scenarios we examined lead to costs greater than or equal to estimates of the social cost of carbon (SCC), wind-majority mixes all cost far less than the SCC.  相似文献   
17.
Nasal polyposis is often encountered in rhinology practice. Those who fail conservative management, a definitive surgery is essential to achieve sufficient ventilation and drainage of the affected sinuses by using either microdebrider or conventional instruments for functional endoscopic sinus surgery (FESS). A prospective study was conducted on 40 cases of nasal polypi in a tertiary care hospital. 20 cases were operated by conventional endoscopic instruments and 20 using the microdebrider. The study aimed at comparing the intra operative (blood loss, duration of surgery) and post operative results (crusting, scarring, discharge, symptoms, recurrence) between the two groups using Lund–Mackay scoring system and the data was statistically analysed. There was no statistically significant difference in surgical outcome for patients when either conventional endoscopic instruments or microdebrider was used. However, there was a significant symptomatic improvement in cases undergoing microdebrider FESS. Microdebrider assisted polypectomy is precise, relatively bloodless surgery though the precision depends on the surgeon’s anatomical knowledge and operative skills. Study substantiates that these instruments are helpful but not a prerequisite for successful outcomes in FESS. The study re-emphasises the utility of the microdebrider to young learning FESS surgeons.  相似文献   
18.
The mechanism of retrograde aortic blood flow is a complex and underreported clinical phenomenon. Complex plaques of the aortic arch are considered high-risk sources of cerebral emboli.1 Aortic plaques situated in the descending thoracic aorta are however often overlooked and in fact can be more frequent potential sources of cerebral embolism through the mechanism of retrograde aortic blood flow. We present the case of an elderly Caucasian female who experienced recurrent posterior circulation embolic strokes where the only possible underlying etiology was found to be an atheroma in the descending thoracic aorta, possibly showering retrograde emboli.  相似文献   
19.
BACKGROUND AND OBJECTIVES: Hepatitis B virus (HBV) may occasionally be transmitted through transfusion of blood units that are hepatitis B surface antigen (HBsAg) negative but HBV DNA positive. Children with beta-thalassemia are particularly susceptible to HBV because they receive multiple blood transfusions. These children have high infection rates despite vaccination against HBV. Post-vaccination infections may be a result of viruses harbouring surface (S)-gene mutations (e.g. G587A) in a region critical for reactivity to antibody to hepatitis B surface antigen (anti-HBs). The true prevalence of HBV in individuals with beta-thalassemia has not been studied previously. PATIENTS AND METHODS: Seventy patients with beta-thalassemia (median age 6 years; range 8 months to 22 years; 49 male), who had received seven to 623 (median 61) units of blood each and three doses (10/20 micro g) of HBV vaccine (Engerix B) before presentation to us, were included in the study; 50 of the 70 patients had received transfusions prior to vaccination. Enzyme-linked immunoassay for serological markers [HBsAg, antibody to hepatitis B core antigen (anti-HBc) and quantitative anti-HBs] and polymerase chain reaction (PCR) followed by Southern hybridization for molecular detection of hepatitis B, was performed on all samples. The PCR-amplified product was cloned, sequenced and the nucleotide and deduced amino acid sequences for the HBV S and polymerase (P) genes were analysed for mutations. RESULTS: Four of 70 (5.7%) individuals with beta-thalassemia were HBsAg positive and 14 (20%) were anti-HBc positive. The prevalence of serological markers increased with number of transfusions (P < 0.01). Of 70 patients, 53 (75.7%) had an anti-HBs titre of > 10 IU/l following vaccination and 17 (24.3%) were non-responders (< 10 IU/l); 22 (31.4%) of the 70 were DNA positive. The frequency of HBV infection in beta-thalassemia was similar in vaccine responders and non-responders. The virus was of subtype ayw (genotype D) in the five DNA-positive samples in which a 388-nucleotide region of the S gene was sequenced. Mutations occurred at 13 positions in the S gene and at 10 positions in the P gene. Hydrophobicity plots revealed differences in amino acid regions 117-165 and 195-211. Some of these amino acid substitutions coincided with the putative cytotoxic T-lymphocyte epitopes of both S and P proteins. CONCLUSIONS: A high frequency of HBV infection was seen using molecular methods in thalassemic patients. The frequency of infection was similar in vaccine responders and non-responders. A number of mutations were observed in the S gene, which could have implications for viral replication as well as virus-host cell interaction.  相似文献   
20.
Objective: To assess concurrent validity, between and within-day reliability of scapular and clavicular digital inclinometer measures. Design: Test–retest and concurrent validity. Setting: Laboratory. Participants: Twenty-three participants with and without shoulder symptoms. Main Outcome Measures: Static positions of scapular upward rotation, anterior/posterior tilting and clavicular elevation were measured between days with an inclinometer and compared to a 3-dimensional electromagnetic tracking system in different positions of sagittal plane humeral elevation (neutral, 30°, 60°, 90°, 120°). The two methods were compared using a two-way Analysis of Variance. Linear regressions at each arm position were also performed to further assess concurrent validity. Results: Between-day reliability demonstrated Intraclass Correlation Coefficients ≥ 0.50 for all comparisons. There were statistically significant differences between methods or interactions of method and arm position for clavicle elevation (p = 0.004, maximum offset between methods 7.7º in the neutral position), and scapular upward rotation (p = 0.001). For scapular upward rotation, the maximum difference between methods was less than 2° across all humeral positions. Clavicle elevation (r = 0.67–0.82) and scapular upward rotation (r = 0.57–0.81) demonstrated higher correlations between measurement methods than scapular anterior/posterior tilt (r = 0.10–0.67). Conclusions: Concurrent validity in assessing scapular upward rotation and clavicle elevation with an inclinometer was shown when compared with electromagnetic tracking. However, the inclinometer method may not have adequate concurrent validity to clinically measure scapular anterior/posterior tilting.  相似文献   
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