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41.
In the surgical treatment of hepatocellular carcinoma and colorectal liver metastasis, it is important to preserve sufficient liver volume after resection in order to avoid post-hepatectomy liver sufficiency and to increase the feasibility of repeated hepatectomyin case of intrahepatic recurrence. Parenchymasparing approach, which minimizes the extent of resection while obtaining sufficient surgical margins, has been developed in open hepatectomy. Although this approach can possibly have positive impacts on morbidity and mortality, it is not popular in laparoscopic approach because parenchyma-sparing resection is technically demanding especially by laparoscopy due to its intricate curved transection planes. "Small incision, big resection" is the words to caution laparoscopic surgeons against an easygoing trend to seek for a superficial minimal-invasiveness rather than substantial patient-benefits. Minimal parenchyma excision is often more important than minimal incision. Recently, several reports have shown that technical evolution and accumulation of experience allow surgeons to overcome the hurdle in laparoscopic parenchymasparing resection of difficult-to-access liver lesions in posterosuperior segments, paracaval portion, and central liver. Laparoscopic surgeons should now seek for the possibility of laparoscopic parenchyma-sparing hepatectomy as open approach can, which we believe is beneficial for patients rather than just a small incision and lead laparoscopic hepatectomy toward a truly minimally-invasive approach.  相似文献   
42.
Eosinophilic cholangitis is a rare disease of which only 31 cases have been reported. Eosinophilic infiltration causes stricture of the bile duct diffusely or locally, and the imaging of eosinophilic cholangitis resembles primary sclerosing cholangitis or cancer of the bile tract. For eosinophilic cholangitis, treatment with steroid is effective and the prognosis is good. Therefore, its accurate diagnosis is very important. Here, we describe a patient with eosinophilic cholangitis who was also diagnosed with idiopathic thrombocytopenic purpura (ITP). He was treated for ITP using prednisolone, the unexpected sudden interruption of which caused severe deterioration of eosinophilic cholangitis and acute cholecystitis. Cholecystectomy and choledochojejunostomy were performed, and the addition of treatment by prednisolone resulted in a good clinical course. This is the first report on eosinophilic cholangitis coexisting with ITP.  相似文献   
43.
Mind wandering (MW) has become a prominent topic of neuroscientific investigation due to the importance of understanding attentional processes in our day‐to‐day experiences. Emerging evidence suggests a critical role for three large‐scale brain networks in MW: the default network (DN), the central executive network (CEN), and the salience network (SN). Advances in analytical methods for neuroimaging data (i.e., dynamic functional connectivity, DFC) demonstrate that the interactions between these networks are not static but dynamically fluctuate over time (Chang & Glover, 2010, NeuroImage, 50(1), 81–98). While the bulk of the evidence comes from studies involving resting‐state functional MRI, a few studies have investigated DFC during a task. Direct comparison of DFC during rest and task with frequent MW is scarce. The present study applies the DFC method to neuroimaging data collected from 30 participants who completed a resting‐state run followed by two runs of sustained attention to response task (SART) with embedded probes indicating a high prevalence of MW. The analysis identified five DFC states. Differences between rest and task were noted in the frequency of three DFC states. One DFC state characterized by negative DN–CEN/SN connectivity along with positive CEN–SN connectivity was more frequently observed during task vs. rest. Two DFC states, one of which was characterized by weaker connectivity between networks, were more frequently observed during rest than task. These findings suggest that the dynamic relationships between brain networks may vary as a function of whether ongoing cognitive activity unfolds in an “unconstrained” manner during rest or is “constrained” by task demands.  相似文献   
44.
Investigations of between‐person variability are enjoying a recent resurgence in functional magnetic resonance imaging (fMRI) research. Several recent studies have found persistent between‐person differences in blood‐oxygenated‐level dependent (BOLD) activation patterns and resting‐state functional connectivity. Conflicting findings have been reported regarding the extent to which (a) between‐person or (b) within‐person cognitive state differences explain differences in BOLD activation patterns. These discrepancies may arise due to statistical analysis choices, parcellation resolution, and limited sampling of task‐fMRI datasets. We attempt to address these issues in a large‐scale analysis of several task‐fMRI paradigms. Using a novel application of multivariate distance matrix regression, we examine between‐person and task‐condition variability estimates across varying levels of “resolution”, from a coarse region‐of‐interest level to the vertex‐level, and across different distance metrics. These analyses revealed that under most circumstances, differences in task conditions explained a greater amount of variance in activation map differences than between‐person differences. However, this finding was reversed when comparing activation maps at a “high‐resolution” vertex level. More generally, we observed that when moving from “low” to “high” resolutions, the variance explained by between‐person differences increased while variance explained by task conditions decreased. We further analyzed the relationships among subject‐level activation maps across all task‐conditions using an unsupervised clustering approach and identified a superordinate task structure. This structure went beyond conventional task labels and highlighted those experimental manipulations across task conditions that produce contrasting versus similar whole‐brain activation patterns. Overall, these analyses suggest that the question of the subject‐ versus task‐effects on BOLD activation patterns is nontrivial, and depends on the comparison “resolution,” choice of distance metric, and the coding of task‐conditions.  相似文献   
45.
46.
Annals of Surgical Oncology - Herpesvirus entry mediator (HVEM) has been suggested to play various roles in cancer biology. The authors report that HVEM expression in tumor cells is associated with...  相似文献   
47.
Hemangioma of the nasal septum, known as “bleeding polyp,” is an occasional lesion in adults. We report two cases of bleeding polyps, that were successfully treated by surgery using the Harmonic Scalpel (HS). Two women (aged 58 and 67 years) presented with unilateral nasal hemangioma, which was revealed by unilateral epistaxis. Both the women were treated by surgical excision using the HS under general and local anesthesia, respectively. Treatment involves surgical excision of the tumor including the mucosa and the underlying perichondrium. HS is an effective tool for the excision of bleeding polyps with less bleeding and less tissue injury.  相似文献   
48.
A titanium Greenfield inferior vena cava filter was used for the treatment of 2 patients with unresectable renal cell carcinomas with tumor thrombi to prevent a fatal pulmonary embolism induced by tumor clots released during systemic interferon therapy and embolization of the primary tumor. After treatment, the size of the renal cell carcinomas at the primary site and the tumor thrombi decreased by 50%. There were no fatal pulmonary embolisms or complications related to the filter during the observation period (24 and 25 months) after therapy. This method may be useful in the prevention of a fatal pulmonary embolism induced by embolization and systemic interferon therapy in these patients.  相似文献   
49.
The concept of differential regulation of certain adhesion molecules on different cell subsets and their relevance to cell functions has emerged in recent years. The initial event in bone remodeling is an increase in osteoclastic bone resorption and cell adhesion between osteoclastic precursors and bone marrow stromal cells or osteoblasts is known to commit the osteoclast development. Here, we show that human osteoblasts can be divided into two subsets based on the expression of the intercellular adhesion molecule (ICAM)-1; ICAM-1+ osteoblasts highly adhered to monocytes, including osteoclast precursors, produced osteoclast differentiation factor (ODF), and induced multinuclear osteoclast-like cell formation. Anti-ODF monoclonal antibody (mAb) did not inhibit the adhesion of monocytes to osteoblastic cells, whereas anti-leukocyte function-associated antigen (LFA)-1, a receptor for ICAM-1, mAb blocked the adhesion. We thereby propose that the higher affinity adhesion via LFA-1/ICAM-1 is prerequisite for efficient function of membrane-bound ODF during osteoclast maturation. The functional characteristics of ICAM-1+ osteoblasts were emphasized further by cell cycle regulation, as manifested by (i) up-regulation of p53 and p21, (ii) reduction of activity of cyclin-dependent kinase (cdk) 6, (iii) underphosphorylation of retinoblastoma protein, (iv) increased Fas but reduced bcl-2 expression, and (v) majority of cells remained at G0/G1 phase. Furthermore, ICAM-1+ osteoblasts were induced by interleukin-1beta (IL-1beta). Taken together, we propose that the differentiation of osteoblasts to ICAM-1+ subpopulation by inflammatory cytokines plays an important role in osteoporosis, which is observed in patients with chronic inflammation, because ICAM-1+ osteoblasts can bias bone turnover to bone resorption, committing osteoclast maturation through cell adhesion with its precursor, and the majority of ICAM-1+ osteoblasts arrested at G0/G1 phase. Such regulation of cell cycle arrest also is an important determinant of the life span of cells in bone in which continuous bone remodeling maintains its homeostasis.  相似文献   
50.
S Nomi  N R Pellis  B D Kahan 《Cancer》1985,55(6):1296-1302
In a methylcholanthrene-induced tumor (MCA-F) model in C3H/HeJ mice, curative resection of a progressive tumor promotes artificial lung metastases following intravenous injection of a highly metastatic cell variant designated clone 9-4. The number of metastatic lung colonies depends upon the status of host immunity at the tumor resection: mice resected 7 or 14 days, but not 28 days after tumor inoculation display significantly retarded postoperative, experimentally induced lung metastases. The number of lung colonies in mice that had tumors resected at 14 days was three times greater than in mice that had 28-day neoplasms resected. Neither therapy with weekly injection of 50 micrograms tumor-specific transplantation antigen, which had been extracted using a single phase of 2.5% 1-butanol (CBE), nor 20 mg/kg cyclophosphamide (CY) alone prevented lung colonization. Assessment of helper-suppressor ratios in the spleen from mice after tumor surgery showed that CBE administration decreased the ratio in mice after resection of 14-day tumors, but not after resection of 28-day tumors. Combined therapy with specific tumor antigen and an antisuppressor cell agent reduced metastases, regardless of the tumor size.  相似文献   
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