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1.
【目的】 探索建设世界一流科技期刊的策略,以助力中国科技期刊冲刺世界一流水平。【方法】 通过研读相关政策和研究文献,结合对NatureScienceThe LancetCell等不同类型的世界一流科技期刊的分析,解析世界一流科技期刊的概念及内涵,探讨建设世界一流科技期刊的充分条件和必要条件,提出建设世界一流科技期刊的建议。【结果】 卓越的办刊理念、全方位的国际化水平、世界一流的人才队伍、先进的经营管理水平以及汇聚一流前沿成果、卓著的科学声望是建设世界一流科技期刊的必要条件。“高、精、尖”和“稳、准、狠”的办刊策略,是建设世界一流科技期刊的充分条件。建设世界一流科技期刊要理性且准确地认知其内涵,始终坚持卓越的办刊理念、国际化战略、人才战略、质量战略和集群化战略。【结论】 中国科技期刊既要扎根祖国大地,又要学习世界一流期刊的成功经验,从办刊的硬实力和软实力方面吸收借鉴,才能探索出具有中国特色的世界一流科技期刊建设路径。  相似文献   
2.
目的 检测分析被诊断为X连锁视网膜色素变性(XLRP)的三个中国家系内的基因突变。设计 基因研究。研究对象 三个中国XLRP家系共27位受试者(其中18人为男性)。方法 由同一医生收集家系成员的详细临床资料并进行眼部检查,采集三个家系的先证者及有条件采血者的外周静脉血,提取基因组DNA。应用PCR技术扩增RPGR和RP2基因的全部外显子和内含子交界区序列,包括RPGR基因15号外显子开放阅读框,产物直接测序进行突变分析。主要指标 临床特征及基因测序结果。结果 基因筛查证实了两个RPGR基因的新型无义突变(c.1541C>G;p.S514X 和 c.2833G>T;p.E945X) 及一个错义突变(c.607G>C;p.A203P)。基因型-表型的相关性分析表明家系3患者在接近ORF15下游位置存在突变,这种突变导致视锥细胞功能的早期丧失。ORF15无义突变的女性携带者临床表型重,呈现出部分显性遗传的特点。结论 本研究证实了三种RPGR基因的新型突变,这一结果扩展了RPGR的突变谱及表型谱。  相似文献   
3.

Purpose

Suppression of respiratory movement of the liver would be desirable for high-precision radiation therapy for liver tumors. We aimed to investigate the effect of our original device-free compressed shell fixation method and breathing instruction on suppression of respiratory movement. The characteristics of liver motion based on the movement of a fiducial marker were also analyzed.

Methods and Materials

First, respiratory amplitudes of the liver with the device-free compressed shell were analyzed from the data of 146 patients. The effect of this shell fixing method on liver movement was evaluated. Second, as another cohort study with 166 patients, interfractional internal motion of the liver for patients fixed in the shell was calculated using the fiducial marker coordinate data of images for position setting before daily irradiation. Third, in another 12 patients, intrafractional internal motion was calculated from the fiducial marker coordinate data using x-ray images before and after irradiation.

Results

The median respiratory movement without the shell, after fixing with the shell, and after instructing on the breathing method with the shell was 14.2 (interquartile range, 10.7-19.8), 11.5 (8.6-17.5), and 10.4 mm (7.3-15.8), respectively. Systematic and random errors of interfractional internal motion were all ≤2 mm in the left-right and anteroposterior directions and 3.7 and 3.0 mm, respectively, in the craniocaudal direction. Systematic and random errors of intrafractional internal motion were all ≤1.3 mm in the left-right and anteroposterior directions and 0.8 and 2.4 mm, respectively, in the craniocaudal direction.

Conclusions

The device-free compressed shell fixation method was effective in suppressing the respiratory movement of the liver. Irradiation position matching using the fiducial marker can correct the interfractional internal motion on each day, which would contribute to the reduction of the margin to be given around the target.  相似文献   
4.
5.
In HIV/AIDS research, few studies to date have evaluated ways to improve parental HIV disclosure practices using feedback from HIV-negative children who have recently experienced this event. We conducted semi-structured in-depth interviews with 20 children (aged 6–15) who were partially to fully aware of their parents’ HIV status in rural Guangxi, China. Of the 20 children, eight children who were of older age (11.38 years in average) endorsed parental HIV disclosure, five discouraged it and seven expressed uncertainty. Children’s different experiences and attitudes towards disclosure were seen to be associated with their family dynamics (especially the parent–child relationship), social support and care, experiences of stigma and discrimination, psychosocial suffering, comprehension of the disease and the children’s age. Our study contributes to building a child-centered comprehensive understanding for Chinese parental HIV disclosure. It is imperative that counselors and community advocates assess and help parents achieve optimal readiness preceding disclosure of their illness to their HIV-negative children.  相似文献   
6.
世界各地均在加速推进教育信息化建设,但快速的 e 化发展,会因民众自身条件的不同造成不均的现象,并导致阶层、地域及群体间的“数位落差”。数位落差是世界各地政府在推动信息化的过程中都无法避免的,大陆地区也不例外。由于中国台湾地区具有与大陆相似的文化氛围和相近的教育发展历史,该文通过梳理和解读中国台湾地区现有的缩减数位落差政策,以期为大陆地区研制专门化政策来应对当前挑战,推进教育信息化的均衡发展提供借鉴。  相似文献   
7.
ImportanceImmunotherapy has emerged as an effective treatment option for the management of advanced cancers. The effects of these immune checkpoint inhibitors in the older patient population has not been adequately assessed.ObjectiveTo understand the impact of aging on CTLA-4 and PDL-1 inhibitors efficacy and immune-related adverse events (irAE) in the context of real-world management of advanced solid cancers.Design, Setting, and ParticipantsThis retrospective study involved all non-study patients with histologically-confirmed metastatic or inoperable solid cancers receiving immunotherapy at Kingston Health Sciences Centre. We defined ‘older patient’ as age ≥ 75. All statistical analyses were conducted under SPSS IBM for Windows version 24.0.Main Outcomes and MeasuresStudy outcomes included immunotherapy treatment response, survival, as well as number, type, and severity of irAEs.ResultsOur study (N = 78) had 29 (37%) patients age <65, 26 (33%) patients age 65–74, and 23 (30%) patients age ≥75. Melanoma, non-small cell lung cancer, and renal cell carcinoma accounted for 70%, 22%, and 8% of the study population, respectively. Distributions of ipilimumab (32%), nivolumab (33%), and pembrolizumab (35%) were similar in the study. The response rates were 28%, 27%, and 39% in the age <65, age 64–74, age ≥75 groups, respectively (P = 0.585). Kaplan-Meier curve showed a median survival of 28 months (12.28–43.9, 95% CI) and 17 months (0–36.9, 95% CI) in the age <65 and age 64–74 groups, respectively; the estimated survival probability did not reach 50% in the age ≥75 group (P = 0.319). There were no statistically significant differences found in terms of irAEs, multiple irAEs, severity of grade 3 or higher, types of irAEs, and irAEs resolution status when comparing between different age groups.Conclusion and RelevanceOur results suggest that patients age ≥75 are able to gain as much benefit from immunotherapy as younger patients, without excess toxicity. Our findings suggest that single agent immunotherapy is generally well-tolerated across different age groups with no significant difference in the type, frequency or severity of irAEs. Future studies evaluating aging and combination immunotherapy are warranted.  相似文献   
8.
PurposeWe previously demonstrated that the functional inactivation of DAL-1 and TOB1 promotes an aggressive phenotype in gastric cancer cells, but the links between both genes and the survival of patients with gastric cancer are unknown. Here, we investigated the correlations of the expression levels of DAL-1 and TOB1 with the progression of gastric cancer.MethodsA total of 270 patients who underwent resectable gastrectomy were included. The expression of DAL-1 and TOB1 was detected by immunohistochemistry.ResultsLow expression of DAL-1 in cancer tissue was significantly associated with tumor site (p < 0.05), histological grade (p < 0.01), depth of invasion (p < 0.05), lymph node metastasis status (p < 0.05), Lauren classification (p < 0.001), and clinical stage (p < 0.01). A lower level of TOB1 was observed in gastric cancer patients with diffuse type disease compared to patients with either intestinal or mixed type disease (p < 0.001). Additionally, Spearman’s correlation analysis revealed that decreased expression of DAL-1 was positively correlated with low TOB1 expression (r=0.304, p < 0.001). The survival analysis showed that low levels of DAL-1 and TOB1 were significantly associated with poor survival of gastric cancer patients (p <0.001 and p < 0.05, respectively).ConclusionThe downregulation of DAL-1 and TOB1 expression is associated with shorter survival of gastric cancer patients. Hence, DAL-1 and TOB1 may be considered potential novel markers for predicting the outcomes of patients with gastric cancer.  相似文献   
9.
In low and middle-income countries mammographic breast cancer screening is prohibitively expensive and a cheaper alternative option is to use ultrasound as the primary screening test. In 2009, China launched a breast cancer screening programme for rural women aged 35–64 years with clinical breast examination coupled with ultrasound as the primary tool. Our study aimed to analyse the cost-effectiveness of breast screening compared to no screening among Chinese rural women. We developed a Markov model to estimate the lifetime costs and effects for rural women aged 35 years from a societal perspective. Asymptomatic women in the intervention arm were screened every 3 years before age 64 years. Breast cancer in the non-screening arm can only be diagnosed on presentation of symptoms. Parameter uncertainty was explored using one-way and probabilistic sensitivity analyses. Compared to no screening, breast cancer screening cost $186.7 more and led to a loss of 0.20 quality-adjusted life years (QALYs). Breast screening was more expensive and did harm to health among rural women with an incremental cost-effectiveness ratio (ICER) of $-916/QALY. The sensitivity analysis identified utility loss from false positives as the factor that most influenced the results, but this did not affect the conclusions. In a rural setting with such low breast cancer incidence, screening for asymptomatic disease is not cost-effective with current screening tools. Priority should be given to ensure that symptomatic women have proper access to diagnosis and treatment at an early stage as this will lead to mortality reductions without the usual screening harms.  相似文献   
10.
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