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51.
本文运用文献计量学方法 分析了由中国中医科学院中医药信息研究所研制开发的"中医临床数据库"(2001~2005)年的中风文献,分析了5年来中风文献的变化,研究了中风文献的主要作者、主要期刊和研究内容的变化和发展.  相似文献   
52.
Intracellular oxygenation is an important parameter for numerous biological studies. While there are a variety of methods available for acquiring in vivo measurements of oxygenation in animal models, most are dependent on indirect oxygen measurements, restraints, or anesthetization. A portable microscope system using a Raspberry Pi computer and Pi Camera was developed for attaching to murine dorsal window chambers. Dual-emissive boron nanoparticles were used as an oxygen-sensing probe while mice were imaged in awake and anesthetized states. The portable microscope system avoids altered in vivo measurements due to anesthesia or restraints while enabling increased continual acquisition durations.  相似文献   
53.
AIM: To investigate the clinical features of the ocular surface in patients with different degrees of myopia. METHODS: A cross-sectional study was conducted involving 122 participants with myopia in Beijing Tongren Hospital from February to June, 2023. After completing the Ocular Surface Disease Index (OSDI) score scale, measurements were taken for refraction, biometric parameters and ocular surface parameters. The prevalence, severity and related parameters of the dry eye among different groups based on axial length (AL) were compared. Correlation analysis was performed between ocular surface parameters and refraction/biometric measurement parameters. RESULTS: Statistically significant differences were observed in refractive error, corneal thickness, anterior chamber depth, and subfoveal choroidal thickness among the groups (all P<0.05). With the increase in AL, the incidence and severity of dry eye increased significantly (P<0.05). Moreover, the tear film break-up time (BUT) shortened (P<0.05), and the corneal fluorescein staining (CFS) points increased significantly (P<0.05). OSDI scores were positively correlated with AL and spherical equivalent (SE; both P<0.05); BUT was negatively correlated with AL, SE, and corneal astigmatism (AST; all P<0.05); Schirmer I test (SIT) results were negatively correlated with AL and SE (both P<0.05). CONCLUSION: AL elongation is a risk factor for dry eye onset in myopic participants. The longer the AL, the more severe the dry eye is, with the increased CFS spots and tear film instability. Additionally, SE and AST exhibit negative correlations with dry eye symptom scores and ocular surface parameters.  相似文献   
54.
We have carried out the first systematic study of the effects of visible light on the homogenous dynamics in the bromate–sulfite–ferrocyanide (BSF) reaction. Under flow conditions, the reaction system displayed photoinduction and photoinhibition behavior, and the oscillatory period decreased with the increase of light intensity, which is due to the fact that light irradiation mainly enhanced the negative process and affected the positive feedback. The light effect on positive and negative feedback is studied by analyzing the period length of pH increasing and decreasing in detail. With the increase of light intensity, the period length of pH increasing decreases monotonically, while the period length of pH decreasing changes nonmonotonically. These results suggest that light could be used as a powerful tool to control homogenous dynamics. Results obtained from numerical simulations are in good agreement with experimental data.

The BSF reaction system displayed photoinduction and photoinhibition behavior under flow conditions. The oscillatory period decreased as the light irradiation mainly enhanced the negative process and affected the positive feedback.  相似文献   
55.
一肾一夹肾血管性高血压动物模型的制作   总被引:1,自引:0,他引:1  
目的研究一肾一夹(1K1C)肾血管性高血压动物模型的制作。方法选用200~220 g体重的SD大鼠,制作1K1C高血压大鼠模型。随机分为正常对照组、单肾对照组(1K)、1K1C组、1K1C+BEA组。使用药物2-溴乙胺氢溴酸盐(BEA)破坏肾髓质。采用尾动脉袖套法测量各组大鼠血压的变化。结果1K组大鼠血压4周后有明显升高,与正常对照组比较,差异有统计学意义(P<0.05),但是1K组大鼠与正常对照组大鼠4周后血压远未达到肾血管性高血压入选标准;1K1C组大鼠血压在1周后开始升高,2周时已达到本实验高血压入选标准;1K1C+BEA组血压升高更明显,4周时血压与1K1C组比较,差异有统计学意义(P<0.05)。结论本方法制作肾血管性高血压模型简单易行,成功率约80%。  相似文献   
56.
BackgroundOur previous study showed that two different regimens of moderate hypofractionated radiotherapy (HFRT) delivered with helical tomotherapy (HT) are well tolerated in older prostate cancer patients. We provide a longterm efficacy and toxicity after > 7 years of follow-up.Patients and methodsThe study recruited 33 patients from February 2009 to July 2011 (76 Gy/34F; Group-1); and 34 from July 2011 to February 2014 (71.6 Gy/28F; 50.4 Gy/25F for the risk of pelvic lymph nodes involvement (LNI) >15%; Group-2). The primary outcomes were biochemical failure (BF), biochemical failure and clinical disease failure (BCDF), progression-free survival (PFS), overall survival (OS), late genitourinary (GU) and gastrointestinal (GI) toxicity.ResultsThe average ages of two groups were 80 and 77 years and the proportions of patients with LNI > 15% were 69.7% and 73.5%, respectively. At the final follow-up in February 2020, 27.3% and 20.6% cases experienced BF, with a median time until BF of 3.3 years. A total of 38.8% patients reached primary endpoints, in which 18 deaths were reported BCDF events (45.5% vs. 32.4%, p = 0.271). There was no significant difference in 7-year PFS (68.6% vs. 74.8%, p = 0.591), BCDF (45.5% vs. 32.4%, p = 0.271) and OS (71.9% vs. 87.5%, p = 0.376) for full set analysis and for subgroup analysis (all p > 0.05). The incidence of grade ≥ 2 late GU (6.2% vs. 6.3%, p = 0.127) and GI toxicities (9.4% vs. 15.6%, p = 0.554) was comparable.ConclusionsIn older patients with localized prostate cancer, two moderate hypofractionated regimens were all well tolerated with similar, mild late toxicities and satisfactory survival, without necessity of prophylactic pelvic node irradiation.Key words: helical tomotherapy, radiation dose hypofractionation, progression-free survival, follow-up studies, prostatic neoplasms, adenocarcinoma  相似文献   
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Once metastatic, melanoma remains one of the most aggressive and morbid malignancies. Moreover, in past decades, the overall survival for advanced unresectable melanoma exhibited a constancy of poor prognosis. Low response rates and serious adverse effects have been characteristic of standard therapy based on a combination of chemotherapeutic agents or immunotherapy with IL-2. For example, the chemotherapy including dacarbazine, carmustin, cisplatin and tamoxifen is known as 'Dartmouth regimen' while the CVD regimen comprises carmustine, vinblastine and dacarbazine. Thus, there is an urgent and critical need to reformulate these bioactive agents using nanoscience and nanotechnology as alternative strategies. This article overviews current design and evaluation of nanomedicine undertaken to address this unmet medical need. The nanomedicines studied include polymeric nanoparticles, liposomes, polymersomes, dendrimers, cubosomes, niosomes and nanodiamonds. In this preclinical article, nanotechnology provides hope for effective treatment of this aggressive and largely treatment-resistant disease.  相似文献   
60.
目的对中国中医药数据库检索系统收录的2000—2009年有关肺癌临床文献进行文献计量学分析,以期给广大医学科研工作者以参考。方法将文献的题名、作者、单位、基金、刊名、主题词等数据导入MicrosoftOfficehccess,对发表时间、来源期刊、发丈机构、基金资助情况等进行统计分析,并采用SPSS13.0软件对关键词进行聚类分析。结果采用“模糊检索”得到文献835篇。我国肺癌临床研究的高生产力地区主要集中在浙江、山东、江苏、广东、河南5地;尚未形成核心作者群,高产作者少;临床用药主要涉及黄芪、党参、人参等;联系比较紧密的学科是病理学、外科学;涉及的治疗仪器是体层摄影术、X线计算机。结论中医药在肺癌临床方面有着广泛的应用,与西医结合发挥其作用价值日趋明显。  相似文献   
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