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11.
Darai E; Leblanc M; Walker-Combrouze F; Bringuier AF; Madelenat P; Scoazec JY 《Human reproduction (Oxford, England)》1998,13(5):1346-1352
We evaluated the immunohistochemical expression of cadherins and CD44
variants in 20 endometriomas, 20 cystadenomas, 20 borderline ovarian
tumours as well as 20 ovarian carcinomas, and the serological and cystic
fluid concentrations of soluble E-cadherin and soluble CD44 standard
(sCD44sdt) in 20 endometriomas, 20 cystadenomas, six borderline and 11
carcinomas of the ovary. In endometriomas, immunostaining of E- and
N-cadherin was negative (20 and 30% respectively). CD44 H, v3 and v6
immunostaining were detected in 63, 10 and 40% respectively. A difference
in immunostaining for E-cadherin was found between endometriomas and
cystadenomas (P < 0.001) and for N- cadherin between endometriomas and
carcinomas (P < 0.001). A difference in CD44H immunostaining was
observed between endometriomas and cystadenomas (P < 0.035) but not with
borderline ovarian tumours and carcinomas. No difference in serum
concentrations of soluble E- cadherins and CD44 standard was found between
the four groups of tumours. Cystic fluid concentrations of E-cadherin were
lower in endometriomas than in borderline tumours and ovarian carcinomas (P
< 0.001). High concentrations of soluble CD44 standard cystic fluid were
found in endometriomas than in other ovarian cysts. Endometriomas and
borderline tumours share alterations of cadherins and CD44 isoforms which
may help in the understanding of the aggressive and invasive potentials of
endometriotic cells.
相似文献
12.
Functional uncoupling of MCM helicase and DNA polymerase activities activates the ATR-dependent checkpoint 总被引:19,自引:0,他引:19
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The ATR-dependent DNA damage response pathway can respond to a diverse group of lesions as well as inhibitors of DNA replication. Using the Xenopus egg extract system, we show that lesions induced by UV irradiation and cis-platinum cause the functional uncoupling of MCM helicase and DNA polymerase activities, an event previously shown for aphidicolin. Inhibition of uncoupling during elongation with inhibitors of MCM7 or Cdc45, a putative helicase cofactor, results in abrogation of Chk1 phosphorylation, indicating that uncoupling is necessary for activation of the checkpoint. However, uncoupling is not sufficient for checkpoint activation, and DNA synthesis by Polalpha is also required. Finally, using plasmids of varying size, we demonstrate that all of the unwound DNA generated at a stalled replication fork can contribute to the level of Chk1 phosphorylation, suggesting that uncoupling amplifies checkpoint signaling at each individual replication fork. Taken together, these observations indicate that functional uncoupling of MCM helicase and DNA polymerase activities occurs in response to multiple forms of DNA damage and that there is a general mechanism for generation of the checkpoint-activating signal following DNA damage. 相似文献
13.
Peripheral T cell lymphoma encompasses lymphomas with a variety of histologic appearances and clinical patterns. Recently, it has been suggested that almost all of the histologic features described under the name of polymorphic reticulosis(PR), lethal midline granuloma, and midline malignant reticulosis can be included in those generally described for malignant lymphomas of peripheral T cell origin(PTCL). There have been few studies of pathogenesis or tissue damage mechanism in PR patients. The need for a precise mechanism for tissue damage has important therapeutic implications. Using immunohistochemical methods with polyclonal anti IL-6 antibody, the authors describe 5 cases of PR with clinically and pathologically typical PR demonstrating a high expression of IL-6. According to classification, 2 cases of grade 1 PR showed the highest expressions, and 2 cases of grade 2 PR with atypical lymphoid cells showed moderate activity, but one case progressed into frank lymphoma(grade 3) and lost IL-6 expression. This strongly implies that some cases of PR have a different mechanism of tissue damage from frank PTCL, despite the one disease spectrum. Further studies on more cases may help clarify the pathogenesis. 相似文献
14.
JP Damsin JY Zambelli R Ma J Roume F Colonna L Hannoun 《Surgical and radiologic anatomy : SRA》1995,17(1):13-17
Summary Varus deformity of the knee is common in young children who have suffered from fulminating purpura. This study was directed at the anatomic features of the vascularisation of the upper end of the tibia that might account for such deformation. It was based on the dissection of 28 anatomic specimens prepared by injection of Indian ink into the vascular trunk. 16 specimens were diaphanised for better analysis of the intracartilaginous distribution of the vessels. The study showed that the vascularisation of the medial condyle of the tibia is poor and of terminal nature, which may explain the occurrence of ischemic growth disorders following fulminating purpura.
Etude de la vascularisation artérielle du condyle médial du tibia chez le foetus
Résumé Les déformations en varus du genou chez les jeunes enfants ayant présenté un purpura fulminans sont fréquentes. Ce travail a pour objet de rechercher les caractéristiques anatomiques de la vascularisation de l'extrémité supérieure du tibia qui peuvent expliquer ces déformations. L'étude porte sur la dissection de 28 pièces anatomiques préparées par injection de l'axe vasculaire à l'encre de Chine. Pour mieux analyser la répartition intra-cartilagineuse des vaisseaux, 16 pièces ont été diaphanisées. Cette étude montre que la vascularisation du condyle médial du tibia est pauvre, de type terminal, ce qui peut expliquer la survenue de troubles de croissance ischémiques dans les suites d'un purpura fulminans.相似文献
15.
Byun BH Lee SW Bae SH Choi JY Kim DG Byun JY Park YM Park DH Kim BS 《Journal of Korean medical science》1999,14(1):97-101
Biliary complications after orthotopic liver transplants are a continuing cause of morbidity and mortality. Biliary stones and sludge are less well known complications of hepatic transplantation, although they have long been recognized. Recently we experienced two cases of biliary stones developed after liver transplantation. One 32-year-old male, who frequently admitted due to recurrent cholangitis, was treated with percutaneous transhepatic biliary drainage and choledochojejunostomy with cholecystectomy. The other 58-year-old male, who had stones in commone bile duct, was treated by endoscopic manipulation. They are in good condition without recurrent bile duct stones or its accompanying complications. Although stones and sludge are relatively infrequent after liver transplantation, surgical or interventional radiologic treatments are usually performed for treatment. 相似文献
16.
Minimally invasive surgery has gained wide acceptance as a method of reducing postoperative pain and curtailing the convalescence period. We have devised a modified surgical technique of laparoscopy-assisted surgery through minilaparotomy. It is a hybridized form of conventional open and laparoscopic surgery and it combines the benefits of both techniques by reducing postoperative pain and scarring as in laparoscopy, but at the same time maintaining the safety of conventional open surgery. From January 1992 to September 1999, we performed laparoscopy-assisted surgery through minilaparotomy in 167 patients. The operative time for laparoscopy-assisted surgery through minilaparotomy ranged from 79 to 290 minutes (mean 125). There was no conversion to open surgery, no peri- or postoperative complications, and only 3 patients needed a blood transfusion at any stage. Pain was significant on the first day but resolved quickly. All patients resumed consistent oral intake on the second day. All patients commenced ambulation by the second postoperative day and were able to resume full ambulatory activity by the fourth postoperative day. The final would size did not exceed 10 cm in size and all patients expressed satisfaction with their wounds. In conclusion, we believe that laparoscopy-assisted minilaparotomy surgery is a truly minimally invasive technique maintaining the advantages of conventional surgery. Our method could become a first-line approach for simple nephrectomy, living donor nephrectomy and radical nephrectomy, as well as surgery for kidney and ureter stones. 相似文献
17.
Prospective payment systems using the diagnostic related group (DRG) mechanism are being phased in for Medicare inpatient hospital care. The purpose of this study was to examine a common neurosurgical procedure (001), craniotomy without trauma, and characterize the cost dynamics of this DRG. All patients (n = 50) treated in this DRG at the Long Island Jewish Medical Center during 1983 had their financial charges exclusive of physician fees examined. The findings were: (a) each hospital service category had wide charge variances around the mean; (b) emergency (ER) admissions were 200% more expensive than nonemergency (non-ER) admissions; (c) ER admissions seemed to have no greater severity of illness than non-ER admissions, but had a significantly different referral pattern (i.e., admission from the ER to a nonneurosurgical service with a subsequent neurosurgical referral); (d) this DRG when grouped into clinical "subproducts" (i.e., craniotomy for tumor, hematoma, hydrocephalus, aneurysm, benign cyst, and other) showed marked charge differences; and (e) the most expensive 25% of patients had five times higher charges than the least expensive 25% for both ER and non-ER admissions. This type of financial analysis may give surgeons a methodology with which to address the problems of cost containment in a more serious manner. 相似文献
18.
Xuan-Mei Piao Ho Won Kang Pildu Jeong Young Joon Byun Hee Youn Lee Kyeong Kim Sung Phil Seo Won Tae Kim Jong-Young Lee Yun-Sok Ha Yung Hyun Choi Sung-Kwon Moon Seok Joong Yun Wun-Jae Kim 《Urologic oncology》2021,39(4):237.e21-237.e29
BackgroundThere is an increasing demand for prognostic immune biomarkers of cancer. The prognostic significance of immune markers has been shown for various cancers, but biomarkers of bladder cancer (BCa) have not been fully evaluated. To clarify the role of human leukocyte antigen DR alpha chain (HLA-DRA) in BCa development, we examined expression of HLA-DRA mRNA in tissue samples of non-muscle invasive bladder cancer (NMIBC) and muscle invasive bladder cancer (MIBC).Materials and MethodsTissues of 96 NMIBC, 43 MIBC and 59 controls comprising noncancerous BCa surrounding tissues were used to examine the expression of HLA-DRA gene by real-time polymerase chain reaction. The expression of up-stream genes regulating HLA-DRA were also measured to explain the role of HLA-DRA in BCa.ResultsPatients with high grade NMIBC showed higher expression of HLA-DRA than those with low grade NMIBC (P < 0.05). In addition, NMIBC patients who progressed to MIBC showed high expression of HLA-DRA mRNA. Kaplan-Meier analysis showed that NMIBC patients with low expression of HLA-DRA had better progression-free survival than those with high expression (P = 0.004). Moreover, the expression of genes regulating HLA-DRA varied in NMIBC and MIBC, indicating a different immunoregulation effect of HLA-DRA in both cancers.ConclusionsHigh expression of HLA-DRA in NMIBC patients has implications for patient stratification strategies, as well as for BCa tumor immunology. 相似文献
19.
Jung Kwon Kim Hoyoung Ryu Myong Kim Eun-Kyung Kwon Hakmin Lee Sang Joon Park Seok-Soo Byun 《BJU international》2021,127(5):567-574
20.
应用四唑盐比色法对5种骨水泥的细胞毒性的测试 总被引:4,自引:1,他引:3
0 引言 应用细胞培养法对牙科材料的生物相容性进行评价是一种简便、有效、经济的方法 .近年来 ,国内外有许多学者报道用 MTT检测细胞活性 ,并认为用 MTT法可以代替活细胞计数、同位素标记进行细胞毒性试验 .我们应用 MTT法对 5种骨水泥的细胞毒性进行了评价 ,并对有关问题进行了讨论 .1 材料和方法1.1 测试材料 1号 :生物水泥 ,2号 :羟基磷灰石人工骨 ,3号 :氰基丙烯酸酯骨水泥 1号 (自制 ) ,4号 :氰基丙烯酸酯骨水泥 2号 (自制 ) ,5号 :氰基丙烯酸酯骨水泥 3号 (自制 ) .阴性对照采用珊瑚 ,阳性对照采用聚氯乙烯 .1.2 实验步骤… 相似文献