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51.
52.
K Nandar LW Ang J Tey L James KM Kyi Win CBE Chee OT Ng JL Cutter YT Wang 《HIV medicine》2018,19(1):59-64
Cross‐matching of records between Singapore's tuberculosis and HIV registries showed that 3.3% of individuals with tuberculosis (TB) were coinfected with HIV (2000?2014), the TB incidence among individuals with HIV infection was 1.65 per 100 person‐years, and 53% of coinfections were diagnosed within 1 month of each other. The findings supported joint prevention programmes for early diagnosis and treatment. 相似文献
53.
目的:观察视神经损伤动物模型在损伤后和不同时期视神经管减压后视觉诱发电位的变化,了解创伤性视神经损伤的手术时机与疗效的关系。方法:实验于2005-03/05在解放军南京军区南京总医院动物实验中心完成。①实验分组:30只新西兰白兔随机分为正常对照组、术后2d减压组、术后7d减压组、术后14d减压组、术后不减压组,每组6只。②造模:除正常对照组外,其余各组在视神经孔中塞入一细端为2mm直径的圆锥软硅胶,阻塞视神经孔,造成视神经的挤压伤。③指标检测:采用图形翻转视觉诱发电位检测损伤前、损伤后1h、减压前1h、减压后2周视功能变化,记录NPN曲线主波(P波)的绝对潜伏期、绝对波幅。正常对照组仅采集一组数据作为对照。结果:30只实验动物均进入结果分析。①正常对照组家兔图形翻转视觉诱发电位检查均引出典型NPN波型曲线,视神经挤压伤后1hNPN波形低阔扁平,P波潜伏期延长,波幅降低。②P波潜伏期:术后2d减压组减压后短于减压前[(71.25±8.51),(86.47±14.28)ms,P<0.05];术后7d减压组减压前后比较差异无显著性(P>0.05);术后14d减压组减压后明显长于减压前[(158.73±15.16),(116.35±17.13)ms,P<0.05]。术后2d减压组和术后7d减压组短于术后不减压组(P<0.01)。术后7,14d减压组和术后不减压组明显长于正常对照组(P<0.01)。③P波波幅:术后2d减压组减压后高于减压前[(5.25±0.78),(4.42±0.42)μV,P<0.05]。术后2d减压组减压后低于术后7d减压组、术后14d减压组(P<0.01),术后14d减压组低于术后7d减压组(P<0.05);术后7d减压组、术后14d减压组、术后不减压组低于正常对照组(P<0.01)。结论:神经元继发性损伤是视功能进行性下降的重要原因,视神经减压术有利于减轻视神经间接损伤,较早期(损伤后48h以内)减压可阻止轴突继发性损伤,避免视功能进一步下降,并在一定程度上逆转视功能的损害。 相似文献
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E. Brie Thumm Denise C. Smith Allison P. Squires Ginger Breedlove Paula M. Meek 《Health services research》2022,57(2):351
ObjectivesTo determine the prevalence of burnout among the midwifery workforce and the association between fixed personal and practice characteristics and modifiable organizational factors, specifically practice environment, to burnout among midwives in the United States.Data SourcePrimary data collection was conducted via an online survey of the complete national roster of certified nurse‐midwives and certified midwives over 3 weeks in April 2017.Study DesignThe study was a cross‐sectional observational survey consisting of 95 items about personal and practice characteristics, respondents'' practice environments, and professional burnout.Data Collection MethodsThe inclusion criterion was actively practicing midwifery in the United States. Data were analyzed with bivariate analyses to determine the association between personal and practice characteristics and burnout. A hierarchal multilinear regression evaluated the interrelationship between personal and practice characteristics, practice environment, and burnout.Principal FindingsOf the almost one third (30.9%) of certified nurse‐midwives and certified midwives who responded to the survey, 40.6% met criteria for burnout. Weak negative correlations existed between burnout and indicators of career longevity: age (r(2256) = −0.09, p < 0.01), years as a midwife (r(2267) = −0.07, p = 0.01), and years with employer (r(2271) = −0.05, p = 0.02). There were significant relationships between burnout score and patient workload indicators: patients per day in outpatient setting (F(5,2292) = 13.995, p < 0.01), birth volume (F(3,1864) = 8.35, p < 0.01), and patient acuity (F(2,2295) = 20.21, p < 0.01). When the practice environment was entered into the model with personal and practice characteristics, the explained variance increased from 6.4% to 26.5% (F(20,1478) = 27.98, p < 0.01).ConclusionsOur findings suggested that a key driver of burnout among US midwives was the practice environment, specifically practice leadership and participation and support for the midwifery model of care. Structural and personal characteristics contributed less to burnout score than the practice environment, implying that prevention of burnout may be achieved through organizational support and does not require structural changes to the provision of perinatal health. 相似文献
56.
S. Akhtar A. J. Bron A. J. Hayes K. M. Meek B. Caterson 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2011,249(3):413-420
Aims
Keratan sulphate (KS) is the predominant glycosaminoglycan (GAG) present in the corneal stroma where it is thought to regulate collagen fibril diameter. In this study we investigated the distribution of KS in normal and keratoconic corneas. 相似文献57.
D. Thuan Nguyen M.D. Iwan B. Harries M.B.B.Ch. B.Sc. Christian Fessas M.R.C.S. Marcel F. Meek M.D. Ph.D. 《Microsurgery》2010,30(3):230-232
This report describes two incidental findings of aberrant branches of the radial digital nerves in the middle finger of a 52‐year‐old man who cut himself with a grinding machine, and in the index finger of a 45‐year‐old female who sustained a flexor sheath infection following a dog bite. In both patients, two equally sized radial digital nerves were found and both nerves originated from one common digital nerve. © 2010 Wiley‐Liss, Inc. Microsurgery, 2010. 相似文献
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59.
MC Chau SF Leung KM Kam KY Cheung WH Kwan KH Yu KW Chiu TC Chan 《Journal of Medical Imaging and Radiation Oncology》2007,51(5):480-484
To assess the dosimetric effect of using interpolated contours in planning intensity‐modulated radiation therapy (IMRT) for advanced T‐stage nasopharyngeal carcinoma. The present study focused on T3–T4 tumours where the proximity of targets to neurological organs poses a stringent test on the feasibility of such an approach. Contours of targets and organs were delineated on CT images of 2.5‐mm interval and a reference IMRT plan was generated. An investigative (INV) IMRT plan was then generated with the same planning protocol, but based on interpolated contours that replaced deleted contours on alternate slices. The reference and INV plans were compared. Regarding target coverage, all targets in the INV plans met the acceptance criteria except for the PTV in one case. Regarding organs, the mean dose to 1% volume of the brainstem and spinal cord in the INV plans were kept below their dose limits. No significant differences in the mean doses to others organs were found. Satisfactory target coverage and protection of critical organs to a degree similar to full‐scale contouring could be achieved with use of interpolated contours. The saving in manpower time for contouring is expected to significantly improve the throughput of the IMRT planning process. 相似文献
60.
Meek B Klaren VN van Haeringen NJ Kijlstra A Peek R 《Investigative ophthalmology & visual science》2000,41(9):2584-2590
PURPOSE: To investigate whether mucosal immune responses directed against the ubiquitous parasite Toxoplasma gondii can be detected in tears of healthy humans. METHODS: Nonstimulated tears and blood were obtained from 62 healthy humans (mean age, 35 +/- 10 [SD] years). Serum anti-T. gondii immunoglobulin titers were determined by Sabin-Feldman (SF) dye test. Western blot analysis was used to compare the anti-T. gondii repertoire in tears and serum, and antibody avidity was determined by urea elution. Diluted tear and serum samples were incubated with the intact parasite to determine whether the antibodies found in tears and serum are capable of binding to surface exposed antigens of T. gondii. RESULTS: Eighty-one percent of the individuals tested had an anti-T. gondii IgA response in their tears, whereas only 23% had evidence of systemic immunity against the parasite. There was no apparent relation between chronic infection and presence of anti-T. gondii IgA in tears. Characteristically, the antigens recognized by the IgA antibodies in tears were often limited to at least one of four antigens with molecular weights of 74, 70, 49, and 34 kDa. The avidity of the anti-T. gondii IgA antibodies in tears was similar to the avidity of serum IgG antibodies. IgA antibodies directed against the 49- and 74-kDa antigens recognized epitopes exposed on the surface of the parasite. CONCLUSIONS: A major finding of this study is that tears of many individuals, chronically infected or not, contain IgA antibodies against T. gondii. It is not known whether these frequently observed antibody responses are the result of common mucosal immune responses against T. gondii or represent the natural antibody repertoire. 相似文献