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91.
92.
Endometrial polyp is a common benign lesion that protrudes into the endometrial surface. The incidence of carcinoma within endometrial polyp is thought to be low, however, postmenopausal women with endometrial polyps are at an increased risk. Endometrial clear cell adenocarcinoma is a distinct and relatively rare subtype of endometrial carcinoma, and recent studies have proposed putative precursor lesions of clear cell adenocarcinoma, namely clear cell endometrial glandular dysplasia (EmGD) and clear cell endometrial intraepithelial carcinoma (EIC). Herein, we describe two cases of clear cell adenocarcinoma present exclusively within endometrial polyp and discuss the association of its precursor. Two postmenopausal Japanese females, 66-year-old (Case 1) and 54-year-old (Case 2) presented with abnormal genital bleeding. Cytological examination of both cases revealed adenocarcinoma, thus, hysterectomy was performed. Histopathological studies demonstrated clear cell adenocarcinoma within exclusively endometrial polyp in both cases. The peculiar finding in Case 1 was presence of atypical glandular cells with large round to oval nuclei and clear cytoplasm within the atrophic endometrial glands in the surrounding endometrial tissue, which corresponded to clear cell EIC. A recent study showed that 33% of uteri had at least one focus of clear cell EmGD in endometrial polyps. Accordingly, clear cell adenocarcinoma and clear cell EmGD can occur in association with endometrial polyps more frequently than previously thought. Therefore, detailed histopathological examination is important in diagnosis of endometrial polyps, especially in the postmenopausal women, moreover cytological examination is a useful tool in the postmenopausal women with endometrial polyps.  相似文献   
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94.
Adenoid cystic carcinoma (AdCC) is a distinct type of carcinoma, and cytological examination has been recognized as a useful tool in its diagnosis. Dedifferentiation is defined as the abrupt transformation of a low‐grade tumor into a tumor with high‐grade components. Albeit extremely rare, dedifferentiated AdCC has been reported: however, the cytological features of this tumor have not been documented. We observed a case in which a 66‐year‐old Japanese male had stenosis and thickness of the lower tracheal and bronchial walls. Cytological smears of a bronchial brush specimen revealed features typical for low‐grade AdCC. However, a few cohesive epithelial cell clusters composed of large, atypical polygonal cells with large nuclei and conspicuous nucleoli also were present. This component was considered to represent dedifferentiated carcinoma. Histopathological study of the resected bronchial tumor revealed dedifferentiated AdCC. The cytological diagnosis of conventional low‐grade AdCC is straightforward in most cases, although extremely rare, dedifferentiated carcinoma can occur within the conventional AdCC, and detection of a dedifferentiated component is possible in a cytological specimen because of obvious nuclear atypia. Therefore, careful observation is needed because cytologic diagnosis of dedifferentiated AdCC can help expedite treatment of this highly aggressive tumor. Diagn. Cytopathol. 2014;42:880–883. © 2013 Wiley Periodicals, Inc.  相似文献   
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96.
Transfemoral endovascular repair has been widely accepted as an effective treatment for type B aortic dissection. However, if the dissection extends to the femoral artery, the transfemoral approach increases the risk of access complications. We describe a case of acute complicated type B aortic dissection involving the dissected bilateral femoral arteries. Successful endovascular repair without access complications was performed through an appropriate access route created by a femoral arterial conduit. We believe that this approach results in reliable cannulation of the true lumen and the reduction of the risk for intimal injury in aortic dissection with the dissected femoral artery.  相似文献   
97.
Ellagic acid (EA), a natural polyphenol found in berries, has high antioxidant capacity. This study aimed to improve EA solubility by complex formation with urea (UR) using solvent evaporation method and evaluate its solubility, antioxidant capacity, and physical properties. The solubility test (25 °C, 72 h) showed that the solubility of EVP (EA/UR = 1/1) was approximately two-fold higher than that of EA (7.13 µg/mL versus 3.99 µg/mL). Moreover, the IC50 values of EA and EVP (EA/UR = 1/1) (1.50 µg/mL and 1.30 µg/mL, respectively) showed higher antioxidant capacity of EVP than that of EA. DSC analysis revealed that the UR peak at 134 °C disappeared, and a new endothermic peak was observed at approximately 250 °C for EVP (EA/UR = 1/1). PXRD measurements showed that the characteristic peaks of EA at 2θ = 12.0° and 28.0° and of UR at 2θ = 22.0°, 24.3°, and 29.1° disappeared and that new peaks were identified at 2θ = 10.6°, 18.7°, and 26.8° for EVP (EA/UR = 1/1). According to 2D NOESY NMR spectroscopy, cross-peaks were observed between the -NH and -OH groups, suggesting intermolecular interactions between EA and UR. Therefore, complexation was confirmed in EA/UR = 1/1 prepared by solvent evaporation, suggesting that it contributed to the improvement in solubility and antioxidant capacity of EA.  相似文献   
98.
We present three cases of self-expandable metallic stent (SEMS) placement using a balloon enteroscope (BE) and its overtube (OT) for malignant obstruction of surgically reconstructed intestine. A BE is effective for the insertion of an endoscope into the deep bowel. However, SEMS placement is impossible through the working channel, because the working channel of BE is too small and too long for the stent device. Therefore, we used a technique in which the BE is inserted as far as the stenotic area; thereafter, the BE is removed, leaving only the OT, and then the stent is placed by inserting the stent device through the OT. In the present three cases, a modification of this technique resulted in the successful placement of the SEMS for obstruction of surgically reconstructed intestine, and the procedures were performed without serious complications. We consider that the present procedure is extremely effective as a palliative treatment for distal bowel stenosis, such as in the surgically reconstructed intestine.  相似文献   
99.
The anterior cingulate gyrus (ACG) is a critical structure for social cognitive processing; the pathology of this structure might be a major source of social dysfunction in schizophrenia. Multiple structural abnormalities of the ACG have been demonstrated in schizophrenia including changes in gray matter volume, white matter microstructures and macroscopic sulcal morphology. However, the interrelationships among these different abnormalities have not been investigated. Thus, the relationship between structural abnormalities in the ACG and social cognition in schizophrenia remains to be elucidated. Magnetic resonance imaging data were acquired at 3.0 T from 26 schizophrenic patients and 20 healthy participants. We performed anterior cingulate cortex (ACC) volumetry, evaluated diffusion tensor imaging of the anterior cingulum, analyzed paracingulate/cingulate sulcus (PCS/CS) morphology and investigated the interrelationships among these measures. We also investigated the association between ACG structural abnormalities and psychopathology, and the social cognition ability of schizophrenic patients as estimated by emotion attribution tasks. Compared with healthy subjects, schizophrenic patients exhibited reduced ACC volume, decreased fractional anisotropy in the anterior cingulum bilaterally and a poorly developed PCS/CS in the left hemisphere. No interrelationship was identified among these measures in the schizophrenic group. Schizophrenic patients performed poorly on emotion attribution tasks. Importantly, clinical symptoms and performance on emotion attribution subtasks were associated with ACC volumes and left PCS/CS variation in different ways. These results suggested that pathology of the ACC, anterior cingulum and PCS/CS is, at least partially, independent and has differential impacts on psychopathology and social cognitive impairment in schizophrenia.  相似文献   
100.
The striatonigral and olivopontocerebellar systems are known to be vulnerable in multiple system atrophy (MSA), showing neuronal loss, astrogliosis, and alpha-synuclein-immunoreactive inclusions. MSA patients who displayed abundant neuronal cytoplasmic inclusions (NCIs) in the regions other than the striatonigral or olivopontocerebellar system have occasionally been diagnosed with variants of MSA. In this study, we report clinical and pathologic findings of MSA patients characterized by prominent pathologic involvement of the hippocampus. We assessed 146 consecutively autopsied MSA patients. Semi-quantitative analysis of anti-alpha-synuclein immunohistochemistry revealed that 12 of 146 patients (8.2%) had severe NCIs in two or more of the following areas: the hippocampal granule cells, cornu ammonis areas, parahippocampal gyrus, and amygdala. In contrast, the remaining 134 patients did not show severe NCIs in any of these regions. Patients with severe hippocampal involvement showed a higher representation of women (nine women/three men; Fisher's exact test, p = 0.0324), longer disease duration (13.1 ± 5.9 years; Mann–Whitney U-test, p = 0.000157), higher prevalence of cognitive impairment (four patients; Fisher's exact test, p = 0.0222), and lower brain weight (1070.3 ± 168.6 g; Mann–Whitney U-test, p = 0.00911) than other patients. The hippocampal granule cells and cornu ammonis area 1/subiculum almost always showed severe NCIs. The NCIs appeared to be ring-shaped or neurofibrillary tangle-like, fibrous configurations. Three of 12 patients also had dense, round-shaped NCIs that were morphologically similar to pick bodies. The patients with Pick body-like inclusions showed more severe atrophy of the medial temporal lobes and broader spreading of NCIs than those without. Immunohistochemistry for hyperphosphorylated tau and phosphorylated TDP-43 revealed minimal aggregations in the hippocampus of the hippocampal MSA patients. Our observations suggest a pathological variant of MSA that is characterized by severe involvement of hippocampal neurons. This phenotype may reinforce the importance of neuronal alpha-synucleinopathy in the pathogenesis of MSA.  相似文献   
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