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1.
目的 运用CT区分脾脏血管性病变与淋巴瘤。方法 回顾性分析20例经手术、穿刺病理学检查证实的脾脏病变的发病年龄、性别、脾脏指数、病变大小、数目、有无液化、钙化、强化幅度、强化方式等特征,并进行统计学分析。结果 20例脾脏病变中,11例血管性病变(6例海绵状血管瘤,3例窦岸细胞血管瘤,2例硬化性血管瘤样结节性转化),9例淋巴瘤;两组间发病年龄、病变大小、数目、有无液化、钙化等差异无统计学意义;两组间脾脏指数、动脉期强化幅度差异具有统计学意义(P<0.05)。5例海绵状血管瘤呈不均匀性强化,1例呈渐进性填充式强化,2例窦岸细胞血管瘤呈“雀斑征”,1例硬化性血管瘤样结节性转化呈“辐轮征”;9例淋巴瘤实质部分均呈均匀、轻中度强化。结论 脾脏血管性病变与淋巴瘤CT表现不同,CT有助于明确诊断。  相似文献   
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3.
Pulmonary thromboembolism (PTE) is an important cause of mortality/morbidity even today despite advancement in clinical understanding as well as diagnostic facilities. Clinical diagnosis of PTE is often challenging because of nonspecific sign/symptoms. Adherence to clinical decision-making protocols and appropriate use of diagnostic modalities like computed tomography pulmonary angiography can resolve the diagnostic dilemma in most cases and help in the overall management of PTE. This article deals with various concerns as well as controversies surrounding accurate diagnosis of PTE as on date.  相似文献   
4.
Particle size analysis in the pharmaceutical industry has long been a source of debate regarding how best to define measurement accuracy; the degree to which the result of a measurement or calculation conforms to the true value. Defining a “true” value for the size of a particle can be challenging as the output of its measurement will differ because of variations in measurement approaches, instrumental differences and calculation methods. Consequently, for “real” particles, a universal “true” value does not exist and accuracy is therefore not a definable characteristic. Accordingly, precision is then a measure of the ability to reproducibly achieve a measurement of unknown relevance.This article proposes, in place of accuracy, a means to define the “appropriateness” of a measurement in line with the critical quality attributes (CQA) of the material being characterized. The decision as to whether the measurement is correct should involve a link to the CQA; that is, correlation should be demonstrated, without which the measured particle size cannot be defined as a critical material attribute.Correspondingly, methods should also be able to provide sufficient precision to demonstrate discrimination relating to variation in the CQA. The benefits and challenges of this approach are discussed.  相似文献   
5.
BackgroundLymph node recurrences (LNR) from colorectal cancer (CRC) still represent a therapeutic challenge, as standardized recommendations have yet to be established. The aim of this study was to analyze short- and long-term oncological outcomes following resection of LNR from CRC.MethodsAll patients with previously resected CRC who underwent histopathologically confirmed LNR resection in 3 tertiary referral centers between 2010 and 2017 were reviewed. Short- and long-term outcomes were analyzed, mainly recurrence-free and overall survival. Further recurrences following LNR resection were also analyzed.ResultsOverall, 18 patients were included. Primary CRC was left-sided in 16 (89%) patients, staged T3-4 in 15 (83%), N+ in 14 (78%) and presented with synchronous metastases in 8 (43%). Median time interval between primary CRC and LNR resections was 31 months. Performed lymphadenectomies were aortocaval (n = 10), pelvic (n = 7), in hepatic pedicle (n = 3) and mesenteric (n = 1). Four patients had associated liver metastases resection. Three (17%) presented with postoperative complications, of which one Clavien-Dindo 3. Fourteen (78%) patients presented with further recurrences after a mean delay of 9 months, with 36% of patients presenting with early (<6 months) recurrence. Five (36%) patients could undergo secondary recurrence resection and 3 (21%) patients radiotherapy. Median overall survival following LNR resection reached 44 months.ConclusionsCurrent results suggest that LNR resection is feasible and associated with improved survival, in selected patients. Longer time interval between primary CRC resection and LNR occurrence appeared to be a favorable prognostic factor whereas multisite recurrence appeared to be associated with impaired long-term survival.  相似文献   
6.

Objective

Comparative survival between neoadjuvant chemotherapy and adjuvant chemotherapy for patients with cT2-4N0-1M0 non–small cell lung cancer has not been extensively studied.

Methods

Patients with cT2-4N0-1M0 non–small cell lung cancer who received platinum-based chemotherapy were retrospectively identified. Exclusion criteria included stage IV disease, induction radiotherapy, and targeted therapy. The primary end point was disease-free survival. Secondary end points were overall survival, chemotherapy tolerance, and ability of Response Evaluation Criteria In Solid Tumors response to predict survival. Survival was estimated using the Kaplan–Meier method, compared using the log-rank test and Cox proportional hazards models, and stratified using matched pairs after propensity score matching.

Results

In total, 330 patients met the inclusion criteria (n = 92/group after propensity-score matching; median follow-up, 42 months). Five-year disease-free survival was 49% (95% confidence interval, 39-61) for neoadjuvant chemotherapy versus 48% (95% confidence interval, 38-61) for adjuvant chemotherapy (P = .70). On multivariable analysis, disease-free survival was not associated with neoadjuvant chemotherapy or adjuvant chemotherapy (hazard ratio, 1.1; 95% confidence interval, 0.64-1.90; P = .737), nor was overall survival (hazard ratio, 1.21; 95% confidence interval, 0.63-2.30; P = .572). The neoadjuvant chemotherapy group was more likely to receive full doses and cycles of chemotherapy (P = .014/0.005) and had fewer grade 3 or greater toxicities (P = .001). Response Evaluation Criteria In Solid Tumors response to neoadjuvant chemotherapy was associated with disease-free survival (P = .035); 15% of patients receiving neoadjuvant chemotherapy (14/92) had a major pathologic response.

Conclusions

Timing of chemotherapy, before or after surgery, is not associated with an improvement in overall or disease-free survival among patients with cT2-4N0-1M0 non–small cell lung cancer who undergo complete surgical resection.  相似文献   
7.
目的探讨CT与MRI在脑梗死后出血性转变(HT)中的诊断价值。方法对2011-01—2014-04我院收治的45例HT患者的临床资料进行回顾性分析,对CT与MRI的检查结果进行对比。结果45例患者中,脑内血肿34例(75.6%),脑梗死病灶内片状、斑点状或条状出血11例(24.4%)。其中大面积脑梗死继发出血24例(53.3%),中等面积继发出血15例(33.3%),小面积脑梗死继发出血6例(13.3%);CT检出HT 10例(22.2%),MRI检出45例(100%),差异有统计学意义(P0.05);在对不同部位的HT检查中,CT检出幕上出血9例(20.0%),幕下出血1例(2.2%);MRI检出幕上出血39例(86.7%),幕下出血6例(13.3%)。MRI对幕上及幕下出血的检出率均优于CT(P0.05)。结论在HT的诊断中,MRI比CT更加准确和敏感,在判断出血时间、指导临床治疗以及预后判断中具有重要意义。  相似文献   
8.
ObjectiveThe detection of abnormal findings on computed tomography (CT) scans of tuberculosis contacts combined with normal plain radiographs contributes to the early detection of tuberculosis. However, the benefit of the early detection of abnormalities for the prevention of active tuberculosis during follow-up requires evaluation.MethodWe conducted retrospective comparison of the existence of CT scans of tuberculosis contacts without findings of active tuberculosis on plain radiographs at a hospital in Japan. Results: Among 243 contacts without CT scans, five developed tuberculosis during follow-up. Among 229 contacts with CT scans, 24 were judged as targets of multi-drug therapy since their CT findings were suggestive of active tuberculosis at the time of the CT screening. Among 205 contacts judged as having latent tuberculous infection with CT screening, three developed tuberculosis diseases during follow-up. Conclusion: CT scans detected abnormal findings among contacts without abnormalities of plain radiographs but there were some contacts that developed tuberculosis diseases among those with contact investigation including CT scan. The value of CT is equivocal considering the balance of true treatment, overtreatment and harm of radiation.  相似文献   
9.
IntroductionPredicting pathological complete response (pCR) for patients receiving neoadjuvant chemotherapy (NAC) is crucial in establishing individualized treatment. Whole-slide images (WSIs) of tumor tissues reflect the histopathologic information of the tumor, which is important for therapeutic response effectiveness. In this study, we aimed to investigate whether predictive information for pCR could be detected from WSIs.Materials and methodsWe retrospectively collected data from four cohorts of 874 patients diagnosed with biopsy-proven breast cancer. A deep learning pathological model (DLPM) was constructed to predict pCR using biopsy WSIs in the primary cohort, and it was then validated in three external cohorts. The DLPM could generate a deep learning pathological score (DLPs) for each patient; stromal tumor-infiltrating lymphocytes (TILs) were selected for comparison with DLPs.ResultsThe WSI feature-based DLPM showed good predictive performance with the highest area under the curve (AUC) of 0.72 among the cohorts. Alternatively, the combination of the DLPM and clinical characteristics offered a better prediction performance (AUC >0.70) in all cohorts. We also evaluated the performance of DLPM in three different breast subtypes with the best prediction for the triple-negative breast cancer (TNBC) subtype (AUC: 0.73). Moreover, DLPM combined with clinical characteristics and stromal TILs achieved the highest AUC in the primary cohort (AUC: 0.82) and validation cohort 1 (AUC: 0.80).ConclusionOur study suggested that WSIs integrated with deep learning could potentially predict pCR to NAC in breast cancer. The predictive performance will be improved by combining clinical characteristics. DLPs from DLPM can provide more information compared to stromal TILs for pCR prediction.  相似文献   
10.
Objective: To observe the clinical effect of modified akupotomye closed lysis under CT guidance on compression of posterior lumbar nerve branch.Methods: Patients were diagnosed by HRCT 3-D reconstruction combined with clinical symptoms and signs.After HRCT three-dimensional reconstruction combined with clinical symptoms and signs, the patients were confirmed as posterior lumbar nerve compression.After CT accurate surface positioning, CT-guided modified akupotomye was used for closed lysis of the posterior lumbar nerve branch.Oswestry Dysfunction Index Questionnaire(ODI) was used for quantitative scoring, 7 days before and after treatment and 6 months after treatment.Results: In 62 cases, 20 cases were cured, with 25 cases markedly effective, 11 cases effective, and 36 cases ineffective.The total effective rate was 90.3%.ODI score: Self-paired t test 7 days before after treatment, P < 0.01;Before treatment and 6 months after treatment, self-paired t test(P < 0.01);Self-paired t-test was performed 7 days after treatment and 6 months after treatment(P > 0.05).Conclusion: With CT precise positioning, the modified akupotomye can be used to do closed lysis, to relieve the adhesion and compression, so that the low back pain can be relieved, with good clinical.The akupotomye closed lysis, combined with modern imaging technology has not only achieved good clinical effect, but also can improve the accuracy, safety and scientificity of akupotomye treatment.  相似文献   
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