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Background/objectivesDuctal adenocarcinoma in the head of the pancreas (PDAC) is usually unresectable at the time of diagnosis due to the involvement of the peripancreatic vessels. Various preoperative classification algorithms have been developed to describe the relationship of the tumor to these vessels, but most of them lack a surgically based approach. We present a CT-based classification algorithm for PDAC based on surgical resectability principles with a focus on interobserver variability.MethodsThirty patients with PDAC undergoing pancreaticoduodenectomy were examined by using a standard CT protocol. Nine radiologists, representing three different levels of expertise, evaluated the CT examinations and the tumors were classified into four categories (A–D) according to the proposed system. For the interobserver agreement, the Intraclass Correlation Coefficient (ICC) was estimated.ResultsThe overall ICC was 0.94 and the ICCs among the trainees, experienced radiologists, and experts were 0.85, 0.76, and 0.92, respectively. All tumors classified as category A1 showed no signs of vascular invasion at surgery. In category A2, 40% of the tumors had corresponding infiltration and required resection of the superior mesenteric vein/portal vein (SMV/PV). One of two tumors in category B2 and two of three in category C required SMV/PV resection. All six patients in category D had both arterial and venous involvement.ConclusionThere is almost perfect agreement among radiologists with different levels of expertise in regards to the local staging of PDAC. For tumors in a more advanced preoperative category, an increased risk for vascular involvement was noticed at surgery.  相似文献   
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Background

Surges in heart rate (HR) and blood pressure (BP) at apnea termination contribute to the hypertension seen in obstructive sleep apnea (OSA). Because childhood OSA prevalence peaks in the preschool years, we aimed to characterize the cardiovascular response to obstructive events in preschool-aged children.

Methods

Clinically referred children aged 3–5 years were grouped by obstructive apnea–hypopnea index (OAHI) into the following: primary snoring (PS) (OAHI ? 1 event/h [n = 21]), mild OSA (OAHI > 1– ? 5 [n = 32]), and moderate to severe (MS) OSA (OAHI > 5 [n = 28]). Beat-to-beat pulse transit time (PTT), an inverse continuous indicator of BP changes, and HR were averaged during the two halves (early and late) and during the peak after (post) each obstructive event and were expressed as percentage change from late- to post-event.

Results

We analyzed 422 events consisting of 55 apneas and 367 hypopneas. A significant post-event increase in HR and fall in PTT occurred in all severity groups (P < .05 for all). A greater response was associated with OSA, nonrapid eye movement sleep (NREM), cortical arousal, hypopneas, and oxygen desaturation (P < .05 for all).

Conclusions

Obstructive events elicit acute cardiovascular changes in preschool children. Such circulatory perturbations have been implicated in the development of hypertension, and our findings complement previous studies to suggest a cumulative impact of snoring on the cardiovascular system from childhood into adulthood.  相似文献   
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《Sleep medicine》2013,14(12):1317-1322
ObjectiveWe aimed to investigate if different childhood obstructive sleep apnea (OSA) subtypes, namely rapid eye movement (REM)-related, nonrapid eye movement (NREM)-related and stage-independent OSA would exert different effects on ambulatory blood pressure (ABP).MethodsData from our previous school-based cross-sectional study were reanalyzed. Subjects who had an obstructive apnea–hypopnea index (OAHI) between 1 and 10 events per hour and a total REM sleep duration of >30 min were included in our analysis. REM-related and NREM-related OSA were defined as a ratio of OAHI in REM sleep (OAHIREM) to OAHI in NREM sleep (OAHINREM) of >2 and <0.5, respectively. The others were classified as stage-independent OSA.ResultsA total of 162 subjects were included in the analysis. In the mild OSA (OAHI, 1–5 events/h) subgroup, no significant differences in any ABP parameters were found between OSA subtypes. On the other hand, in subjects with moderate OSA (OAHI, 5–10 events/h), the REM-related OSA subtype had a significantly lower daytime systolic blood pressure (SBP) z score (−0.13 ± 0.90 cf 1.15 ± 0.67; P = .012) and nighttime SBP z score (0.29 ± 1.06 cf 1.48 ± 0.88, P = .039) than the stage-independent OSA subtype. Linear regression analyses revealed that OAHINREM but not OAHIREM was significantly associated with both daytime (P = .008) and nighttime SBP (P = .042) after controlling for age, gender, and body size.ConclusionChildren with obstructive events mainly in REM sleep may have less cardiovascular complications than those with stage-independent OSA.  相似文献   
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目的:探讨影响原发性肝癌术后行经肝动脉化疗栓塞(TACE)患者无瘤生存的因素.方法:回顾性分析121例手术切除后1~2个月内行TACE治疗的原发性肝癌患者的临床及随访资料,计算患者治疗后的累积无瘤生存率,分析影响无瘤生存的相关因素.结果:121例患者术后1,2,3年的无瘤生存率分别为72.73%,46.21%,28.93%.经单因素分析筛选后,进入COX比例风险模型的各临床变量中,肿瘤的分化程度(P=0.040),肿瘤大小(P=0.002)及有无血管癌栓(P=0.039)对模型贡献有统计学意义.结论:分化程度、肿瘤的大小及有无血管癌栓是影响肝癌术后行TACE近期复发的独立危险因素.  相似文献   
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目的 评估职业性急性1,2-二氯乙烷中毒患者应用糖皮质激素所致骨量减少与血脂、血钙的相关性。方法 选取某院2009年~2012年期间应用糖皮质激素治疗的职业性急性1,2-二氯乙烷中毒患者38例,采用双能X线骨密度仪测定相关部位的骨密度,记录低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、总胆固醇(CHOL)、甘油三酯(TRIG)、血清总钙(TCa)等临床资料,资料录入和统计采用SPSS统计软件包。结果 LDL-C、CHOL、TCa对骨量存在影响(P<0.05),而HDL-C、TRIG则对骨量无影响(P>0.05)。结论 职业性急性1,2-二氯乙烷中毒患者应用糖皮质激素,可引起骨量减少或骨质疏松,严格控制血脂可能有助于减少骨量丢失。  相似文献   
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H. Hosni  O. Selim  M. Abbas  A. Fathy 《Andrologia》2013,45(2):120-127
Lead causes male reproductive impairment among painters, but information is still limited. Therefore, the effect of lead on semen quality and reproductive endocrinal function in those patients was investigated. A case series of 27 infertile painters were subjected to semen analysis, measuring of blood lead level (PbB) and serum levels of endocrinal parameters including follicle‐stimulating hormone (FSH), luteinising hormone (LH), testosterone (T) and prolactin (PRL). Significantly lower sperm count and motility were found in those with duration of exposure (≥15 years), but no significant difference was found for PbB and serum levels of FSH, LH, PRL and T. A significant negative correlation between PbB and spermatic count and motility was observed, while there was no significant correlation between PbB and all endocrinal parameters. Patients with PbB ≥ 20 μg dl?1 showed a significant decrease in sperm motility and increase in testosterone alone among all measured hormones. But the observed decrease in sperm count did not reach a significant level. It is concluded that infertile painters are at risk of lead‐related influence on semen quality, especially sperm motility and increased testosterone level without significant affection of other reproductive endocrinal parameters.  相似文献   
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