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41.
A case of polypoid carcinosarcoma of the esophagus is presented. Histologically the bulk of the tumor consisted of a sarcomatous tissue having large foci of osseous and cartilagenous differentiation and infiltrating deeply the wall, whereas a superficially, invasive squamous cell carcinoma associated with insitu carcinoma was located at the base and luminal surface of the polypoid tumor. Intermingling of the carcinomatous and sarcomatous elements was found only in areas where they appeared to be collided. Ultrastructurally the sarcomatous portion contained cells with fibroblastic features but with no typical epithelial characteristics. Immunoperoxidase staining of the paraffinembedded histologic sections for keratin proteins revealed, however, some positive spindle cells indicative of epithelial nature in the sarcomatous area, but the great majority of the sarcoma cells were devoid of keratin. These combined findings strongly suggest that the sarcomatous component in our case of true carcinosarcoma is derived from mesenchymal transformation (metaplasia) of the squamous carcinoma cells. The findings were discussed in light of the previous pertinent literature. ACTA PATHOL, JPN. 34: 669–678, 1984. 相似文献
42.
This study aims to resolve a paradox. Experiments measuring alpha band power report an event related decrease (desynchronization) in alpha activity, whereas those measuring evoked alpha report synchronization. During a recognition memory task with human subjects, we measured the evoked (phase locked) and induced (not phase locked) alpha response. The findings reveal that evoked alpha is due to a transient phase locking (at about 100-200 ms poststimulus) of three alpha sub-bands which can be observed only at parieto-occipital sites. In contrast, induced alpha shows a widespread pattern of desynchronization at most recording sites. Thus, opposite alpha responses occur within similar time windows. Evoked alpha synchronization may reflect cortical inhibition which serves to increase the signal to noise ratio for activation processes following immediately later. 相似文献
43.
Damodaran Shivashankar Bullock Brenna Ekwenna Obi Nayebpour Mehdi Koizumi Naoru Sindhwani Puneet Ortiz Jorge 《International urology and nephrology》2021,53(3):439-446
International Urology and Nephrology - Delayed graft function (DGF) is a manifestation of acute kidney injury uniquely framed within the transplant process and a predictor of poor long-term graft... 相似文献
44.
Ryosuke Takahashi Yukihiro Kajita Yohei Harada Yusuke Iwahori Masataka Deie 《Journal of orthopaedic science》2021,26(2):213-218
BackgroundAlthough the clinical outcomes of arthroscopic rotator cuff repair (ARCR) have been reported, few studies have focused on diabetic patients. We investigated and compared the clinical results of ARCR in patients with and without diabetes.MethodsThis retrospective study involved 195 consecutive patients who underwent ARCR from 2015 to 2018 in our hospital. Twenty-seven and 168 shoulders were assigned to diabetes and non-diabetes groups, respectively. Diabetic patients with poor control were preoperatively hospitalized for perioperative diabetic control. We evaluated range of motion (ROM), Japanese Orthopaedic Association shoulder (JOA) score, Constant Shoulder Score, and University of California, Los Angeles (UCLA) score preoperatively and at 6 months and 1 year post-ARCR. Rates of rotator cuff retear 1 year post-ARCR and preoperative and postoperative stiff shoulder were also evaluated. We compared the results between groups and analyzed them statistically. A p-value of <0.05 was considered statistically significant.ResultsPreoperative ROM, JOA score, Constant Shoulder Score and UCLA scores showed significant improvement at post-ARCR in both groups (p < 0.05). On comparing the groups, although preoperative JOA score and Constant Shoulder Score were significantly lower in diabetes group than in non-diabetes group (diabetic/non-diabetic group; 60.0/65.3 for JOA score; p = 0.003, 59.7/64.2 for Constant Shoulder Score; p = 0.003), there was no significant difference postoperatively (6 months post-ARCR; 88.0/89.7 for JOA score; p = 0.783, 88.1/88.6 for Constant Shoulder Score; p = 0.597, 1 year post-ARCR; 96.7/95.4 for JOA score; p = 0.238, 96.6/95.4 for Constant Shoulder Score; p = 0.248). Furthermore, preoperative and postoperative stiff shoulder and retear rates were not significantly different between groups (p = 0.152, p = 0.344, p = 0.347, and p = 0.563, respectively).ConclusionDiabetic patients showed comparable clinical results with non-diabetic patients post-ARCR. Perioperative diabetic control may be recommended for preoperatively uncontrolled diabetic patients. 相似文献
45.
Nathan Williams Katie Korneffel Naoru Koizumi Jorge Ortiz 《American journal of surgery》2021,221(5):1093-1103
African Americans (AA) are disproportionately affected by end-stage renal disease (ESRD) and have worse outcomes following renal transplantation. Autosomal dominant polycystic kidney disease (ADPKD) is the most common genetic condition leading to ESRD necessitating transplant. We explored this population with respect to race by conducting a retrospective analysis of the UNOS database between 2005 and 2019. Our study included 10,842 (AA n = 1661; non-AA n = 9181) transplant recipients whose primary diagnosis was ADPKD. We further stratified the AA ADPKD population with respect to blood groups (AA blood type B n = 295 vs AA non-B blood type n = 1366), and also compared this cohort to AAs with a diagnosis of DM (n = 16,706) to identify unique trends in the ADPKD population. We analyzed recipient and donor characteristics, generated survival curves, and conducted multivariate analyses. African American ADPKD patients waited longer for transplants (924 days vs 747 days P < .001), and were more likely to be on dialysis (76% vs 62%; p < .001). This same group was also more likely to have AA donors (21% vs 9%; p < .001) and marginally higher KDPI kidneys (0.48 vs 0.45; p < .001). AA race was a risk factor for delayed graft function (DGF), increasing the chance of DGF by 45% (OR 1.45 95% CI 1.26–1.67; p < .001). AA race was not associated with graft failure (HR 1.10 95% CI 0.95–1.28; p = .21) or patient mortality (HR 0.84 95% CI 0.69–1.03; p = .09). Racial disparities exist in the ADPKD population. They should be continually studied and addressed to improve transplant equity. 相似文献
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48.
Makita Ayu Nagao Tomoaki Miyoshi Ken-ichi Koizumi Yohei Kurata Mie Kondo Fumikazu Shichijo Satoru Hirooka Masashi Yamaguchi Osamu 《Clinical and experimental nephrology》2021,25(9):981-987
Clinical and Experimental Nephrology - The progression of chronic kidney disease (CKD) depends on the extent of fibrosis in the kidneys; however, a renal biopsy is necessary to evaluate the... 相似文献
49.
Kentaro Ariyoshi Yota Hiroyama Naoya Fujiwara Tomisato Miura Kosuke Kasai Akifumi Nakata Yohei Fujishima Valerie Swee Ting Goh Mitsuaki A Yoshida 《Journal of radiation research》2021,62(1):73
Alopecia is one of the common symptoms after high-dose radiation exposure. In our experiments, neonatal mice that received 7 Gy X-ray exhibited defects in overall hair growth, except for their cheeks. This phenomenon might suggest that some substances were secreted and prevented hair follicle loss in the infant tissues around their cheeks after radiation damage. In this study, we focused on exosome-like vesicles (ELV) secreted from cheek skin tissues and back skin tissues, as control, and examined their radiation protective effects on mouse fibroblast cell lines. We observed that ELV from irradiated cheek skin showed protective effects from radiation. Our results suggest that ELV from radiation-exposed cheek skin tissue is one of the secreted factors that prevent hair follicle loss after high-dose radiation. 相似文献
50.
Protein tyrosine phosphatases (PTPases) balance the action of tyrosine kinases to maintain a set level of cellular tyrosine phosphorylation. Increases in tyrosine phosphorylation produced by transformation with constitutively active tyrosine kinases can initiate cellular proliferation. PTPases may act as tumor suppressors to counteract the transforming potential of oncogenic kinases. However, recent evidence suggests that PTPases have the potential to act as positive mediators of mitogenic signaling. If PTPases are acting as tumor suppressors, the expression of an inactive PTPase may cause an increase in overall tyrosine phosphorylation of cellular proteins, resulting in cellular transformation. Alternatively, overexpression of PTPases that play a positive role in signal transduction might also lead to proliferation. The role that each PTPase plays may depend in the cellular context in which it is expressed. 相似文献