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81.
BACKGROUND AND OBJECTIVES: The indication of preoperative portal vein embolization (PVE) has been expanded to hepatocellular carcinoma, cholangiocellular carcinoma (CCC), hepatic metastasis, and gallbladder (GB) cancer as well as hilar cholangiocarcinoma (hCC). However, biliary cancers sometimes cause peritoneal dissemination. PATIENTS AND METHODS: We performed our preoperative trans-ileocecal-vein PVE (TIPE) method on 14 (3 GB cancer, 1 CCC, and 10 hCC), whose estimated residual liver volume was <30%. RESULTS: Out of 14 patients, peritoneal dissemination was encountered in two patients with GB cancer and one with hCC (21.4%) during our procedure. The estimated residual liver volume was 37.4 +/- 2.7% at 14 days after PVE in patients without predisposing cholangitis, while those in patients with cholangitis was 29.3 +/- 1.3% (P = 0.0002). No major complication due to the procedure was encountered in this series. CONCLUSIONS: PTPE could be the first choice for patients with hCC, hepatocellular carcinoma, and hepatic metastases. Although the TIPE proposed here has some potential disadvantages, we would recommend it especially for patients with GB cancer because of its high potential to cause cancerous peritonitis. When a patient had predisposing cholangitis, radical operation should be scheduled on >21 days after PVE rather than on 14 days.  相似文献   
82.
在收治的直肠癌患者89例中,发生骶前静脉丛大出血3例,2例死亡,死亡率2.2%。为避免这一严重并发症的发生,结合经验才识分析了骶前静脉丛大出血的原因、预防及处理措施,供同道参考。  相似文献   
83.
Detecting overlapping communities is essential to analyzing and exploring natural networks such as social networks, biological networks, and citation networks. However, most existing approaches do not scale to the size of networks that we regularly observe in the real world. In this paper, we develop a scalable approach to community detection that discovers overlapping communities in massive real-world networks. Our approach is based on a Bayesian model of networks that allows nodes to participate in multiple communities, and a corresponding algorithm that naturally interleaves subsampling from the network and updating an estimate of its communities. We demonstrate how we can discover the hidden community structure of several real-world networks, including 3.7 million US patents, 575,000 physics articles from the arXiv preprint server, and 875,000 connected Web pages from the Internet. Furthermore, we demonstrate on large simulated networks that our algorithm accurately discovers the true community structure. This paper opens the door to using sophisticated statistical models to analyze massive networks.  相似文献   
84.
We assessed healing of a 3.5 cm autograft transport segment, denuded of periosteum, and docked to the healthy distal femur with an intramedullary nail. We hypothesized that healing relates to proximity to the healthy distal femur and to mechanical loading patterns. Total bone area, area of new bone apposition, and quality of new bone formed in the 2 weeks after surgery, and area and degree of perfusion 16 weeks after surgery were measured as a function of proximity and loading patterns (as defined by the major and minor centroidal axes, CA). At 16 weeks, no significant differences in early bone apposition or perfusion were observed as a function of distance from the healthy distal femur. Qualitatively, bone was well perfused, both vascularly and pericellularly, and highly remodeled. When cross‐sections were pooled from distal to proximal through the docking zone and normalized for total bone area, significant differences in the amount of early proliferative woven bone were related to loading patterns. In contrast, no differences in normalized perfusion area were attributable to loading patterns. Furthermore, early bone apposition and perfusion decreased with increasing radial distance from the bone surface toward the intramedullary nail. Finally, no differences were observed in areas of resorption within the docking zone compared to baseline levels measured in the control (in bone removed to create the defect zone at the time of surgery). Interestingly, infilling of resorption spaces within docking zone specimens related significantly to predominant loading patterns, where areas within the major CA exhibited significantly more infilling. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:1657–1664, 2010  相似文献   
85.
86.
Alport syndrome (ATS) is a genetically heterogeneous nephropathy with considerable phenotypic variability and different transmission patterns, including monogenic (X‐linked/autosomal) and digenic inheritance (DI). Here we present a new series of families with DI and we discuss the consequences for genetic counseling and risk assessment. Out of five families harboring variants in more than one COL4 gene detected by next generation sequencing (NGS), minigene‐splicing assay allowed us to identify four as true digenic. Two families showed COL4A3/A4 mutations in cis, mimicking an autosomal dominant inheritance with a more severe phenotype and one showed COL4A3/A4 mutations in trans, mimicking an autosomal recessive inheritance with a less severe phenotype. In a fourth family, a de novo mutation (COL4A5) combined with an inherited mutation (COL4A3) triggered a more severe phenotype. A fifth family, predicted digenic on the basis of silico tools, rather showed monogenic X‐linked inheritance due to a hypomorphic mutation, in accordance with a milder phenotype. In conclusion, this study highlights the impact of DI in ATS and explains the associated atypical presentations. More complex inheritance should be therefore considered when reviewing prognosis and recurrence risks. On the other side, these findings emphasize the importance to accompany NGS with splicing assays in order to avoid erroneous identification of at risk members.  相似文献   
87.
The concentration of extracellular potassium in red blood cell concentrates (RCCs) increases during storage, leading to risk of hyperkalemia. A potassium adsorption filter (PAF) can eliminate the potassium at normal blood transfusion. This study aimed to investigate the potassium adsorption capacity of a PAF during rapid blood transfusion. We tested several different potassium concentrations under a rapid transfusion condition using a pressure bag. The adsorption rates of the 70‐mEq/l model were 76·8%. The PAF showed good potassium adsorption capacity, suggesting that this filter may provide a convenient method to prevent hyperkalemia during rapid blood transfusion.  相似文献   
88.

Background:

Lung cancer is the leading cause of cancer-related deaths worldwide. The typical and atypical carcinoid (TC and AC), the large-cell neuroendocrine carcinoma (LCNEC) and the small-cell lung cancers (SCLC) are subgroups of pulmonary tumours that show neuroendocrine differentiations. With the rising impact of molecular pathology in routine diagnostics the interest for reliable biomarkers, which can help to differentiate these subgroups and may enable a more personalised treatment of patients, grows.

Methods:

A collective of 70 formalin-fixed, paraffin-embedded (FFPE) pulmonary neuroendocrine tumours (17 TCs, 17 ACs, 19 LCNECs and 17 SCLCs) was used to identify biomarkers by high-throughput sequencing. Using the Illumina TruSeq Amplicon-Cancer Panel on the MiSeq instrument, the samples were screened for alterations in 221 mutation hot spots of 48 tumour-relevant genes.

Results:

After filtering >26 000 detected variants by applying strict algorithms, a total of 130 mutations were found in 29 genes and 49 patients. Mutations in JAK3, NRAS, RB1 and VHL1 were exclusively found in SCLCs, whereas the FGFR2 mutation was detected in LCNEC only. KIT, PTEN, HNF1A and SMO were altered in ACs. The SMAD4 mutation corresponded to the TC subtype. We prove that the frequency of mutations increased with the malignancy of tumour type. Interestingly, four out of five ATM-mutated patients showed an additional alteration in TP53, which was by far the most frequently altered gene (28 out of 130; 22%). We found correlations between tumour type and IASLC grade for ATM- (P=0.022; P=0.008) and TP53-mutated patients (P<0.001). Both mutated genes were also associated with lymph node invasion and distant metastasis (P⩽0.005). Furthermore, PIK3CA-mutated patients with high-grade tumours showed a reduced overall survival (P=0.040) and the mutation frequency of APC and ATM in high-grade neuroendocrine lung cancer patients was associated with progression-free survival (PFS) (P=0.020).

Conclusions:

The implementation of high-throughput sequencing for the analysis of the neuroendocrine lung tumours has revealed that, even if these tumours encompass several subtypes with varying clinical aggressiveness, they share a number of molecular features. An improved understanding of the biology of neuroendocrine tumours will offer the opportunity for novel approaches in clinical management, resulting in a better prognosis and prediction of therapeutic response.  相似文献   
89.

Background and purpose

Rosai-Dorfman disease (RDD) is a rare, lymphoproliferative disorder of uncertain etiology. The Central Nervous System (CNS) is a very rare site for RDD and only a few imaging appearances have been described. The purpose of this study is to present the largest series of cases in the CNS imaging literature to increase familiarity with this entity and further identify features that may distinguish RDD from meningioma.

Materials and methods

Findings from imaging examinations in 10 patients with pathologically confirmed RDD were retrospectively reviewed. Two radiologists evaluated the lesion location, shape, size, number, edge, cerebral edema, homogeneous or heterogeneous appearance, attenuation and signal intensity, degree of enhancement, and the relation between lesions and meninges.

Results

RDD in CNS showed similar features in imaging: an extra-axial, well-circumscribed, dura-based mass, isodense or hyperdense on CT, isointensity on T1-weighted imaging and isointensity with hypointensity on T2-weighted imaging. The mass enhanced markedly and homogeneously after the administration of contrast agent and demonstrated dural tail sign in all cases. Significant perifocal edema was associated with the masses. Remarkably, seven patients (77.8%) showed strong hypointensity within isointensity on T2-weighted or FLAIR images and no calcification was observed in CT images or pathologic specimens.

Conclusions

Although RDD in the CNS is a rare process, it should be considered in the differential diagnoses for meningioma. We believe that a typical representation of hypointensity irrelevant to calcification on T2-weighted or FLAIR images can suggest the diagnosis of RDD.  相似文献   
90.
目的观察胞磷胆碱钠、甘露醇和依达拉奉联合治疗大面积脑梗死的临床疗效。方法 32例大面积脑梗死患者分为2组,每组16例,2组患者均给予保持呼吸道通畅、吸氧、营养支持等常规治疗,在此基础上,对照组患者给予甘露醇治疗,观察组患者给予胞磷胆碱钠、甘露醇、依达拉奉联合治疗,14 d为1个疗程。治疗1个疗程后,对2组患者的治疗效果及并发症发生率进行比较。结果对照组和观察组患者总有效率分别为68.75%和87.50%,观察组患者治疗总有效率高于对照组(P<0.05)。2组患者治疗第7、14天神经功能缺损评分均显著低于治疗前(P<0.05),治疗前及治疗第7天2组患者神经功能缺损评分比较差异无统计学意义(P>0.05);治疗第14天,观察组患者神经功能缺损评分显著低于对照组(P<0.05)。观察组和对照组患者并发症发生率分别为31.25%、68.75%,观察组患者并发症发生率显著低于对照组(P<0.05)。结论胞磷胆碱钠、甘露醇和依达拉奉联合治疗可明显改善大面积脑梗死患者的临床症状和神经功能。  相似文献   
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