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61.
目的 比较基于不同体位定位CT下不同勾画者勾画保乳术后部分乳腺外照射(EB-PBI)靶区差异。方法 2016-2017年间27例保乳术后拟行EB-PBI的患者在自由呼吸状态下序贯完成俯卧位及仰卧位模拟定位3DCT扫描。5位勾画者分别在两种不同体位CT图像上基于术腔金属夹完成瘤床(TB) 靶区勾画和临床靶区(CTV) 的构建。比较两种体位不同勾画者间的靶体积、变异系数(COV)、匹配指数(MD)差异。结果 无论仰卧位还是俯卧位时,不同勾画者所勾画TB、CTV均不同(P<0.001、P=0.001、P<0.001、P=0.001)。俯卧位时不同勾画者CTV交集比仰卧位大5.79cm3(P=0.011)。仰卧位时5位勾画者的COVCTV显著大于俯卧位(P=0.014)。仰卧位时5位勾画者的MDTBTB及MDTBCTV均显著劣于俯卧位(P<0.001、P=0.001)。结论 与仰卧位相比,基于俯卧位构建EB-PBI靶区可显著减少不同勾画者间差异,提高勾画者间的一致性。因此,在自由呼吸状态下基于俯卧位施行EB-PBI更为合理。  相似文献   
62.
Biliary tract cancers (BTCs) are a group of invasive neoplasms, with increasing incidence and dismal prognosis. In advanced disease, the standard of care is represented by first-line chemotherapy with cisplatin and gemcitabine. In subsequent lines, no clear recommendations are currently available, highlighting the need for novel therapeutic approaches.The PI3K/AKT/mTOR pathway is a core regulator of cell metabolism, growth and survival, and is involved in BTCs carcinogenesis and progression. Mutations, gene copy number alterations and aberrant protein phosphorylation of PI3K, AKT, mTOR and PTEN have been thoroughly described in BTCs and correlate with poor survival outcomes.Several pre-clinical evidences state the efficacy of PI3K/AKT/mTOR pathway inhibitors in BTCs, both in vitro and in vivo. In the clinical setting, initial studies with rapamycin analogs have shown interesting activity with an acceptable toxicity profile. Novel strategies evaluating AKT and PI3K inhibitors have risen serious safety concerns, pointing out the need for improved patient selection and increased target specificity for the clinical development of these agents, both alone and in combination with chemotherapy.This review extensively describes the role of the PI3K/AKT/mTOR pathway in BTCs and examines the rationale of its targeting in these tumors, with particular focus on clinical activity, toxicities and perspectives on further development of PI3K/AKT/mTOR pathway inhibitors.  相似文献   
63.
BackgroundPartial hepatectomy has been used to treat patients with resectable hepatocellular carcinoma (HCC) which spontaneously ruptured. It is still controversial as to whether emergency partial hepatectomy (EmPH) should be carried out at the time of rupture, or the patients should initially be managed by operative or non-operative treatment to stop the bleeding, followed by staged early or delayed partial hepatectomy when the patient's condition becomes stable.MethodsConsecutive 10-year patients with ruptured HCC managed at our center were included in this study. Patients who underwent partial hepatectomy were further subdivided into the EmPH group, the staged early partial hepatectomy (SEPH) group, and the staged delayed partial hepatectomy (SDPH) group. Univariate and multivariate analyses of factors affecting overall survival(OS) were conducted before and after propensity score matching analyses amongst the included patients. OS, postoperative mortality, recurrence free survival (RFS), and peritoneal metastatic rates were compared. The risk factors of peritoneal metastases were determined using the COX regression analysis.ResultsThe 130 patients who underwent partial hepatectomy were subdivided into the EmPH group (surgery at the time of rupture, n = 30), the SEPH group (surgery ≤ 8 days of rupture, n = 67), and the SDPH group (surgery > 8 days of rupture, n = 33). The remaining 86 patients underwent non-surgical treatment. Partial hepatectomy was an independent predictor of better OS (HR 2.792, P < 0.001). For resectable HCC, the 30-day mortality, OS, and RFS were similar between the EmPH group, and the staged partial hepatectomy (SPH) group which included the patients who underwent SEPH and SDPH. The SEPH group had significantly better OS and RFS. Multivariate COX regression analysis demonstrated that SDPH was strongly associated with postoperative peritoneal dissemination (OR 28.775, P = 0.003).ConclusionPartial hepatectomy provided significantly better survival than non-surgical treatment for patients who presented with ruptured HCC. Early partial hepatectomy within 8 days of rupture which included EmPH (carefully selected) and SEPH, resulted in significantly less patients with peritoneal dissemination and better long-term survival outcomes (especially RFS) than SDPH.  相似文献   
64.
ObjectiveTo increase the likelihood of finding a causative genetic variant in patients with a focal segmental glomerulosclerosis (FSGS) lesion, clinical and histologic characteristics were analyzed.Patients and MethodsIndividuals 18 years and older with an FSGS lesion on kidney biopsy evaluated at Mayo Clinic from November 1, 1999, through October 31, 2019, were divided into 4 groups based on clinical and histologic characteristics: primary FSGS, secondary FSGS with known cause, secondary FSGS without known cause, and undetermined FSGS. A targeted gene panel and a customized gene panel retrieved from exome sequencing were performed.ResultsThe overall rate of detection of a monogenic cause was 42.9% (21/49). Individuals with undetermined FSGS had the highest rate of positivity (87.5%; 7/8) followed by secondary FSGS without an identifiable cause (61.5%; 8/13) and secondary FSGS with known cause (33.3%; 5/15). Four of 5 (80%) individuals in the latter group who had positive genetic testing results also had a family history of kidney disease. Univariate analysis showed that family history of kidney disease (odds ratio [OR], 13.8; 95% CI, 3.7 to 62.4; P<.001), absence of nephrotic syndrome (OR, 8.2; 95% CI, 1.9 to 58.1; P=.004), and female sex (OR, 5.1; 95% CI, 1.5 to 19.9; P=.01) were strong predictors of finding a causative genetic variant in the entire cohort. The most common variants were in the collagen genes (52.4%; 11/21), followed by the podocyte genes (38.1%; 8/21).ConclusionIn adults with FSGS lesions, proper selection of patients increases the rate of positive genetic testing significantly. The majority of individuals with undetermined FSGS in whom the clinical presentation and histologic parameters are discordant had a genetic diagnosis.  相似文献   
65.
《Saudi Dental Journal》2021,33(7):656-660
PurposeKnowledge about the most prevalent types of Kennedy classifications is of great value and will enlighten dental students, dental technicians, and practitioners regarding the treatment needs of their patients, ultimately leading to better treatment outcomes. The aim was to determine the prevalence of various Kennedy classifications among patients attending clinics at the College of Dentistry at King Saud bin Abdulaziz University for Health Sciences and King Abdulaziz Dental Center, National Guard Health Affairs, who were seeking treatment for partial edentulism.MethodsAn observational cross-sectional study was conducted by visualizing cast models for partially edentulous patients. Kennedy classification, age, gender, and treatment design were recorded from the lab request sheets that were attached to the casts in the labs at both the College of Dentistry at King Saud bin Abdulaziz University for Health Sciences and King Abdulaziz Dental Center, National Guard Health Affairs. The statistical analyses were performed with SPSS version 20.0 utilizing frequency and Pearson’s and Spearman’s correlation tests.ResultsKennedy Class I (45.0%) was the most prevalent pattern in both dental arches, followed by Class III (26.2%). Next was Class II (23.3%), while Class IV was the least prevalent (5.4%).ConclusionKennedy Class I was the most noted classification in our patient population. As age increases, there is an increased tendency toward Class I and II.  相似文献   
66.
Cortical bone and its microstructure are crucial for bone strength, especially at the long bone diaphysis. However, it is still not well-defined how imaging procedures can be used as predictive tools for mechanical bone properties. This study evaluated the capability of several high-resolution imaging techniques to capture cortical bone morphology and assessed the correlation with the bone's mechanical properties. The microstructural properties (cortical thickness [Ct.Th], porosity [Ct.Po], area [Ct.Ar]) of 11 female tibial diaphysis (40–90 years) were evaluated by dual-energy X-ray absorptiometry (DXA), high-resolution peripheral-quantitative-computed-tomography (HR-pQCT), micro-CT (μCT) and histomorphometry. Stiffness and maximal torque to failure were determined by mechanical testing. T-Scores determined by DXA ranged from 0.6 to −5.6 and a lower T-Score was associated with a decrease in Ct.Th (p ≤ 0.001) while the Ct.Po (p ≤ 0.007) increased, and this relationship was independent of the imaging method. With decreasing T-Score, histology showed an increase in Ct.Po from the endosteal to the periosteal side (p = 0.001) and an exponential increase in the ratio of osteons at rest to those after remodelling. However, compared to histomorphometry, HR-pQCT and μCT underestimated Ct.Po and Ct.Th. A lower T-Score was also associated with significantly reduced stiffness (p = 0.031) and maximal torque (p = 0.006). Improving the accuracy of Ct.Po and Ct.Th did not improve prediction of the mechanical properties, which was most closely related to geometry (Ct.Ar). The ex-vivo evaluation of mechanical properties correlated with all imaging modalities, with Ct.Th and Ct.Po highly correlated with the T-Score of the tibial diaphysis. Cortical microstructural changes were underestimated with the lower resolution of HR-pQCT and μCT compared to the histological ‘gold standard’. The increased accuracy did not result in an improved prediction for local bone strength in this study, which however might be related to the limited number of specimens and thus needs to be evaluated in a larger collective.  相似文献   
67.
ObjectivesDespite its use in determining nigrostriatal degeneration, the lack of a consistent interpretation of nigrosome 1 susceptibility map-weighted imaging (SMwI) limits its generalized applicability. To implement and evaluate a diagnostic algorithm based on convolutional neural networks for interpreting nigrosome 1 SMwI for determining nigrostriatal degeneration in idiopathic Parkinson's disease (IPD).MethodsIn this retrospective study, we enrolled 267 IPD patients and 160 control subjects (125 patients with drug-induced parkinsonism and 35 healthy subjects) at our institute, and 24 IPD patients and 27 control subjects at three other institutes on approval of the local institutional review boards. Dopamine transporter imaging served as the reference standard for the presence or absence of abnormalities of nigrosome 1 on SMwI. Diagnostic performance was compared between visual assessment by an experienced neuroradiologist and the developed deep learning-based diagnostic algorithm in both internal and external datasets using a bootstrapping method with 10000 re-samples by the “pROC” package of R (version 1.16.2).ResultsThe area under the receiver operating characteristics curve (AUC) (95% confidence interval [CI]) per participant by the bootstrap method was not significantly different between visual assessment and the deep learning-based algorithm (internal validation, .9622 [0.8912–1.0000] versus 0.9534 [0.8779-0.9956], P = .1511; external validation, 0.9367 [0.8843-0.9802] versus 0.9208 [0.8634-0.9693], P = .6267), indicative of a comparable performance to visual assessment.ConclusionsOur deep learning-based algorithm for assessing abnormalities of nigrosome 1 on SMwI was found to have a comparable performance to that of an experienced neuroradiologist.  相似文献   
68.
《Clinical breast cancer》2022,22(7):e825-e831
IntroductionThe tubulin inhibitor, eribulin, improves survival for previously treated advanced breast cancer (ABC) compared to chemotherapy of physician's choice, including vinorelbine, an older anti-tubulin. Vinorelbine is commonly still used after eribulin, but potentially risks cross-resistance and its efficacy in this setting is unproven.Materials and MethodsA retrospective analysis of all patients who received vinorelbine after prior eribulin (VAE) 2011-2015 and a parallel cohort of consecutive patients who received vinorelbine without prior eribulin (VWE) for previously treated ABC between 2005 and 2011. Patient demographics, histopathological features, treatment duration and responses were recorded. The primary endpoint was progression-free survival from date of first vinorelbine for each cohort. Secondary endpoints included radiological response rate, and overall survival (OS).ResultsThirty-five VAE and 103 VWE patients were identified, all female, 71.4% and 78.6% were ER positive/HER2 negative, 8.6% and 6.8% HER2 positive, and 20.0% and 14.6% triple negative for VAE and VWE cohorts, respectively. The median number of lines of chemotherapy lines prior to vinorelbine was 4 (range 2-6) and 2 (range 0-4), respectively. Fifteen VAE patients (42.9%) received ≥1 line of chemotherapy between eribulin and vinorelbine. VAE and WWE Patients received a median of 3 cycles of vinorelbine (range 1-9 and 1-12, respectively). The median progression-free survival for VAE patients was 2.1 months and 2.0 months for VWE patients. No VAE patients were progression-free at 24 weeks, compared to 15.5% of VWE patients. Median OS from commencing vinorelbine was 4.3 months for VAE and 6.4 months for VWE patients.ConclusionVinorelbine was of limited benefit after prior eribulin in our study, suggesting cross-resistance. Even without prior eribulin, only 15% of patients experienced clinical benefit from vinorelbine monotherapy.  相似文献   
69.
There have been limited studies of subjective tongue function over long‐term follow‐up in spite of swallowing and articulation disorders are common complications of glossectomy. To assess long‐term subjective swallowing and articulation function after partial glossectomy. A total of 63 patients with the mobile tongue cancer who underwent partial glossectomy without reconstruction were interviewed to score their swallowing and articulation function on a 100‐point scale. The relation of this subjective scoring to the perioperative data was subjected to multivariate analysis. The mean patient age was 53·4 (19–81) years, and the mean follow‐up duration was 78·9 (14–277) months. Mean swallowing and articulation function score was 87·7 ± 6·1 and 88·6 ± 5·4. Age, follow‐up duration, T stage and resection volume were significantly correlated with swallowing function (= 0·026, 0·029, 0·016, 0·002, respectively); follow‐up duration was correlated with articulation function (= 0·039). Patients who undergo partial glossectomy without reconstruction generally demonstrate good function on long‐term follow‐up. Subjective dysfunction was correlated with larger resection volume, older age and shorter follow‐up duration.  相似文献   
70.
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