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61.
62.
Background: Intraductal carcinoma and cribriform (IDC/C) tumor features are well-established prognosticators of biochemical recurrence (BCR), metastasis, and prostate cancer (PCa)-specific mortality. However, approximately 70% of PCa patients undergoing a radical prostatectomy are IDC/C negative, yet up-to 20% of these patients progress and experience BCR. Thus, tumor histopathologic characteristics such as IDC/C alone are limited in their ability to predict disease progression. Conversely, several nomograms such as Cancer of the Prostate Risk Assessment-Surgery (CAPRA-S) have been developed to aid in the prognostication of BCR, but not yet widely applied in clinical settings. Materials and methods: In this study, we assessed the combined prognostic utility of IDC/C, and CAPRA-S for BCR in 3 PCa patient cohorts. Results: CAPRA-S+IDC/C improved the predictive accuracy of BCR in all 3 cohorts (P < .001). Specifically, among IDC/C negative cases, CAPRA-S improved the prognostication of BCR in low-risk (Cohort 1; P < .001, Cohort 2; P < .001, Cohort 3; P = .003), intermediate (Cohort 1; P < .001, Cohort 2; P = .006, Cohort 3; P = .03) and high-risk (Cohort 1-3; P < .001) patients. Conversely, IDC/C improved the prognostication of BCR among CAPRA-S low-risk (Cohorts 1; P < .001 and Cohort 3; P = .003) patients. Conclusion: Our results suggest the investigation of histopathological IDC/C features in CAPRA-S low-risk patients and conversely, nomogram CAPRA-S among IDC/C negative patients improves the identification of patients likely to experience BCR, which would otherwise be missed through current assessment regimens. These patients can be offered more intensive monitoring and adjuvant therapies upfront to circumvent the development of recurrent cancer or overtreatment at the time of surgery.  相似文献   
63.
Medical interactions around reproduction are increasingly extending beyond the physician's office and onto the Internet, where negotiation with medical authority occurs in complex and dynamic ways. Recently, scholars have noted the Internet's potential for creating spaces where women can dialogue with and reconstruct medical authority, yet this growing body of work is overwhelming heteronormative. This paper thus interrogates how lesbian women use the Internet to challenge, deploy, and rework medical authority around reproduction while navigating the transition to parenthood. I draw from 17 online journals authored by lesbian couples during the conception, pregnancy, and birth of their first child, each spanning between 18 months and 2 years, in order to understand how the transition process unfolds over time. I argue that lesbian couples engage with medical authority when seeking affirmation and normalisation yet discard and publicly reject the heteronormative assumptions that accompany reproductive medicine. Further, they chart a new process that I term ‘constructing queer mother‐knowledge’, in which they critique and balance knowledges from institutionalised medicine, their own bodies, and their queer communities. With this new concept, I complicate understandings of lesbian mothers‐to‐be and their interactions with medical authority as they build subversive families.  相似文献   
64.
目的采用Meta分析方法评价18F-脱氧葡萄糖正电子发射计算机体层摄影(18F-FDG PET/CT)和增强CT(CECT)诊断经导管肝动脉化疗栓塞术(TACE)术后存活或复发病灶的临床价值。方法根据PRISMA报告规范开展Meta分析。检索PubMed、Embase、Cochrane Library、Web of Science、中国知网、万方和维普数据库中18F-FDG PET/CT和CECT诊断TACE术后存活或复发病灶的临床研究,时间至2019-04。由2位研究人员独立筛选文献、提取资料,根据诊断准确性研究质量评价工具-2(QUADAS-2)评价纳入研究的偏倚风险后,采用Stata 12.0软件进行Meta分析,计算其汇总敏感度(Sen)和特异度(Spe),绘制受试者工作特征曲线(SROC)并计算曲线下面积(AUC)。结果共纳入10篇18F-FDG PET/CT及13篇CECT诊断TACE术后存活或复发病灶的原始研究,分别包括322例患者的467个病灶和748例患者的943个病灶。Meta分析显示,18F-FDG PET/CT诊断TACE术后存活或复发病灶的Sen=0.92(95%CI为0.87~0.94)、Spe=0.95(95%CI为0.82~0.99)、AUC=0.97(95%CI为0.93~0.99);CECT诊断TACE术后存活或复发病灶的Sen=0.72(95%CI为0.66~0.78)、Spe=0.99(95%CI为0.93~1.00)、AUC=0.87(95%CI为0.83~0.89)。此外,CECT诊断TACE术后存活或复发Sen(Z=2.34,P=0.02)和AUC(Z=2.21,P=0.03)值低于18F-FDG PET/CT,差异有统计学意义。结论相比于CECT,18F-FDG PET/CT对TACE术后存活或复发病灶具有较高诊断效能,可视为TACE术后存活或复发病灶有效的影像学诊断方法。  相似文献   
65.
AimTo compare the accuracy of the inverted greyscale CT versus the conventional CT in the assessment of post-operative spinal orthopaedic implants and osseous fusion.Methods50 patients who had CT as part of their routine spinal implant follow up were evaluated for the presence of fusion, fracture and loosening with conventional CT and with greyscale inverted CT images. 3 independent observers assessed the images 2 months apart. Diagnostic performance (sensitivity and specificity) of the conventional and greyscale inversion images relative to the reference standard were calculated. Agreement with the reference standard was assessed using Cohen's kappa for conventional and greyscale inversion images.ResultsCorrect classifications increased when using the greyscale inverted CT images for each reader compared to conventional CT images (40–46, 39 to 42 and 41 to 44 (out of 50)). Inverted images demonstrated better agreement with the reference standard than conventional grayscale images for assessment of fusion (kappa of 0.588 for inverted CT versus 0.484 for conventional CT) and loosening (kappa 0.386 for inverted versus 0.293 for conventional). Sensitivity was increased for assessment of fusion and loosening. McNemar's test performed for assessment of sensitivity differences showed statistical significance (p = 0.038 for fusion and p = 0.0313 for loosening).ConclusionGreyscale inversion CT is a useful adjunct which has advantages (improved sensitivity and better agreement) over conventional CT imaging in cases of fusion and loosening of metallic implants following spinal instrumentation. We recommend the use of both the greyscale inversion CT images and conventional CT imaging when assessing post-operative spinal orthopaedic implants.  相似文献   
66.

Background

Bone mineral density (BMD) has been found to improve after parathyroidectomy (PTX) in patients with primary hyperparathyroidism. There are few data on the effect of PTX on BMD in normocalcemic and normohormonal primary hyperparathyroidism.

Methods

A retrospective analysis of 92 primary hyperparathyroidism patients who underwent PTX between 2004 and 2012 with pre- and post-PTX dual-energy x-ray absorptiometry was performed. Within-person changes in BMD pre- and post-PTX were analyzed using log linear mixed models, stratified by biochemical status.

Results

Bone mineral density increased post-PTX in the whole cohort at the lumbar spine (+2.5%), femoral neck (+2.1%), and total hip (+1.9%) and decreased at the one-third radius (–0.9%). On comparison of BMD changes by profile, BMD increased in those with the typical profile at the lumbar spine (3.2%), femoral neck (2.9%), and total hip (2.9%) but declined at the one-third radius (–1.5%). In contrast, BMD improved only at the femoral neck (4.3%) in the normohormonal group and did not change at any site in the normocalcemic group. The typical group had a greater increase in BMD over time at the femoral neck and total hip compared with normocalcemic patients.

Conclusion

Our results indicate that the skeletal benefit of PTX was attenuated in normocalcemic and normohormonal patients, suggesting that skeletal changes after PTX may depend on biochemical profile.  相似文献   
67.
68.
目的:建立大黄特征化学成分和抗氧化活性相关联的二维指纹图谱,研究大黄抗氧化活性物质。方法:利用高效液相多检测器联用的抗氧化活性成分在线检测体系,对大黄中化学成分进行检测,共鉴定出大黄中化学成分15种;其中8种具有抗氧化活性;然后采用清除效率为指标对各活性成分的抗氧化活性进行评价。结果:结果发现化合物葡萄糖紫丁香酸、腺嘌呤、没食子酸、儿茶素或表儿茶素、双花母草素、2-O-桂皮酰-没食子酰葡萄糖等具有较强的清除ABTS·+的活性,而蒽醌类成分对ABTS·+的清除作用较弱。结论:采用HPLC-ABTS-DAD-Q-TOF/MS对大黄中的抗氧化活性成分进行快速分析鉴定,初步阐明大黄在抗氧化环节起作用的效应物质。  相似文献   
69.
IntroductionDespite advancements in surgical techniques complications like implant failure is very common after the fixation of intertrochanteric fractures. Classifying these complex fractures based on plain radiographs underestimates the complexity of these fractures which in turn leads to complications. We propose a comprehensive classification of the intertrochanteric fractures based on 3D Non Contrast Computed Tomography (3D NCCT) scan.Material and methodsA total of 102 patients (51 males and 51 females) with intertrochanteric fractures were included in this study conducted over a time period of 22 months in a Tertiary care center in North India. NCCT proximal femur of the intertrochanteric fracture patients was done to formulate a new CT classification system and classify all fractures. Intra and inter-observer reliability was tested using kappa variance.ResultsNew classification system was proposed which included 3 main and a total of 6 groups. All the fractures were classifiable into the new system. Kappa variance of the study showed a good intra and interobserver reliability (0.95 and 0.90) proving clinical agreement of the classification.ConclusionThis new 3D-CT based classification has the advantages of being easy, comprehensible with high intra and inter-observer reliability. This 3DCT based classification can prove to be useful to detect occult intertrochanteric fractures undetectable in plain radiographs as well as choosing the optimum treatment plan.  相似文献   
70.
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