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101.
Enos Tangke Arung Irawan Wijaya Kusuma Sri Purwatiningsih Seong-Soo Roh Chae Ha Yang Soohyeon Jeon Yong-Ung Kim Edi Sukaton Joko Susilo Yuli Astuti Britanto Dani Wicaksono Ferry Sandra Kuniyoshi Shimizu Ryuichiro Kondo 《Journal of acupuncture and meridian studies》2009,2(4):306-308
We investigated the leaves of Kleinhovia hospita, a plant which has been traditionally used in Indonesia as phytotherapy to cure liver disease, to describe antioxidant materials from plant sources. K. hospita leaves were extracted with methanol and further partitioned into n-hexane, diethyl ether, and ethyl acetate. The antioxidant activity of each fraction and the residue was assessed using a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method and their cytotoxicity on HepG2 liver cancer cells was determined by a MTT assay. The K. hospita leaf methanol extract showed strong antioxidant activity (96%) compared with vitamin C (98%) by the DPPH method and the measured activity from the subsequent extracts of the methanol extract were 48.9% for n-hexane, 74.0% for diethyl ether, 84.3% for ethyl acetate, and 77.1% for the residue. The MTT assay showed the cytotoxicity of the methanol extract on HepG2 cells at 14%, 76%, and 80% at concentrations of 50μg/mL, 87.5μg/mL, and 125μg/mL, respectively. Leaf extracts of the medicinal plant K. hospita showed potent antioxidant activity and moderate cytotoxicity on HepG2 liver cancer cells. 相似文献
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Percutaneous Radiofrequency Ablation of Pulmonary Metastases from Colorectal Carcinoma: Prognostic Determinants for Survival 总被引:2,自引:0,他引:2
Yan TD King J Sjarif A Glenn D Steinke K Morris DL 《Annals of surgical oncology》2006,13(11):1529-1537
Background Preliminary results have shown that percutaneous radiofrequency ablation (RFA) may play a useful role in patients with inoperable lung tumors. This series evaluated the prognostic features for survival in nonsurgical candidates who underwent percutaneous RFA of pulmonary metastases from colorectal carcinoma.Methods Fifty-five patients not suitable for surgery underwent percutaneous RFA for colorectal pulmonary metastases. All clinical and treatment-related data were collected prospectively. The primary end point of the study was overall survival, defined from the time of RFA intervention. Univariate and multivariate analyses were performed to identify statistically significant prognostic parameters for overall survival.Results The overall median survival was 33 months (range, 4–40 months), with actuarial 1-, 2-, and 3-year survival of 85%, 64%, and 46%, respectively. Univariate analysis demonstrated that largest size of lung metastasis (P < .001), location of lung metastases (P = .032), and repeat percutaneous RFA for pulmonary recurrence (P = .024) were statistically significant for overall survival. Multivariate analysis demonstrated that largest size of lung metastasis >3 cm was independently associated with a reduced overall survival (P = .003).Conclusions Percutaneous lung RFA may play a useful role in nonsurgical candidates with colorectal pulmonary metastases. However, the survival benefit of this interventional procedure for patients with a pulmonary metastasis >3 cm was limited. 相似文献
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M. Adelaide Asnaghi Philipp Jungebluth Manuela T. Raimondi Sally C. Dickinson Louisa E.N. Rees Tetsuhiko Go Tristan A. Cogan Amanda Dodson Pier Paolo Parnigotto Anthony P. Hollander Martin A. Birchall Maria Teresa Conconi Paolo Macchiarini Sara Mantero 《Biomaterials》2009,30(29):5260-5269
Cell and tissue engineering are now being translated into clinical organ replacement, offering alternatives to fight morbidity, organ shortages and ethico-social problems associated with allotransplantation. Central to the recent first successful use of stem cells to create an organ replacement in man was our development of a bioreactor environment. Critical design features were the abilities to drive the growth of two different cell types, to support 3D maturation, to maintain biomechanical and biological properties and to provide appropriate hydrodynamic stimuli and adequate mass transport. An analytical model was developed and applied to predict oxygen profiles in the bioreactor-cultured organ construct and in the culture media, comparing representative culture configurations and operating conditions. Autologous respiratory epithelial cells and mesenchymal stem cells (BMSCs, then differentiated into chondrocytes) were isolated, characterized and expanded. Both cell types were seeded and cultured onto a decellularized human donor tracheal matrix within the bioreactor. One year post-operatively, graft and patient are healthy, and biopsies confirm angiogenesis, viable epithelial cells and chondrocytes. Our rotating double-chamber bioreactor permits the efficient repopulation of a decellularized human matrix, a concept that can be applied clinically, as demonstrated by the successful tracheal transplantation. 相似文献
106.
Tristan Monchal Emmanuel Hornez Stéphane Bourgouin Fabrice Sbardella Yoann Baudoin Christophe Butin Etienne Salle Hervé Thouard 《American journal of surgery》2010,199(4):e45
Jejunal diverticulosis is a rare malformation that is often asymptomatic. Complications might be similar to those occurring in large-bowel diverticula but also include a much more particular event: intestinal obstruction due to migration and impaction of enterolith formed inside diverticula. This is a very uncommon entity; diagnosis and management are thus often delayed. Mostly surgical exploration is necessary because obstruction symptoms are unresponsive to medical treatment. The authors report a new case of enterolith ileus in a 74-year-old man, due to jejunal diverticulosis, and its successful surgical management in emergency. Only 39 similar cases have ever been reported in the literature. 相似文献
107.
108.
Increased nucleotide excision repair in cisplatin-resistant ovarian cancer cells: role of ERCC1-XPF 总被引:19,自引:0,他引:19
Increased platinum-DNA adduct removal has been shown by several DNA repair assays to be associated with cisplatin resistance in the A2780/C-series human ovarian cancer model system. In the present study, we provide further evidence that the resistance phenotype of these cell lines is due, in part, to enhanced nucleotide excision repair (NER). Cisplatin resistance was found to be associated with increased UV resistance. Northern blot analysis revealed that increased expression of ERCC1 was also associated with cisplatin resistance in this panel. Several other NER genes were found to be constitutively overexpressed in the most resistant cell line, C200, as compared with the parental A2780 cells. A plasmid substrate containing a site-specific cisplatin adduct was used to measure the nucleotide excision activity of cell extracts prepared from cisplatin-sensitive and -resistant cells. Using this in vitro assay, extracts prepared from C200 cells exhibited approximately 3-fold more activity than extracts prepared from A2780 cells, similar to the difference in UV sensitivity. Complementation of A2780 extracts with ERCC1-XPF protein resulted in approximately 2-fold increased activity, but had little effect on excision in C200 extracts. Overall, these results support a role for the ERCC1-XPF endonuclease as a determinant of increased NER in this cisplatin resistance model. 相似文献
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The authors describe the clinical presentation, investigation, and surgical management of two cases of benign ivory osteoma of the craniofacial skeleton. In the first case, a bony mass located over the frontal region had become a cosmetic burden to the patient, and she requested removal with minimal morbidity. Accordingly, an endoscopic procedure, with minimal access incisions located behind the hairline, was devised. In the second case, the patient, a Jehovah's Witness, presented with a long history of slowly enlarging bony masses over the maxilla and in the pterygopalatine space. She finally requested surgical intervention when the symptoms of pain related to fifth nerve compression at the foramen ovale became intolerable. Key aspects of the preoperative and perioperative management strategies used to avoid blood transfusion are detailed, as is the surgical approach, which included a bicoronal scalp flap with temporary removal of the zygomatic arch and the coronoid process. Finally, the etiology, histology, and natural history of ivory osteomas are discussed. 相似文献