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71.
Atul K Madan Constantine T Frantzides Christopher L Tebbit William C Park Nakka V Aruna Kumari Nina Shervin 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2004,8(2):191-193
BACKGROUND: Laparoscopic suturing and tying constitute advanced minimally invasive surgery skills. Developing proficiency in the standard methods with needle drivers is often an arduous process. Recent advances in laparoscopic instrumentations has allowed for easier methods of suturing and tying. This study investigated the hypothesis that the use of a specialized suturing device and a specialized tying device allows inexperienced medical students to suture and tie laparoscopically. METHODS: Preclinical medical students who had not received any training in open or laparoscopic surgery were included in this investigation. Each student was given a 5-minute demonstration of a specialized suturing device and a specialized tying device. The medical students were not allowed to deploy either device before actual use. After the demonstration, each student was given the device to use in a porcine model. Times were recorded and a subjective grade was given for each student. RESULTS: Twenty medical students were involved in this study. All medical students were able to complete the task of suturing and tying. The average time to suture was 104.6 seconds and the average time to tying was 31.2 seconds. The average subjective performance grade was 90 (out of 100). CONCLUSION: Specialized devices are easy to learn and use for laparoscopic suturing and tying with minimal instruction even for inexperienced medical students. Even surgeons who are not well versed in laparoscopic surgery should be able to suture and tie with certain laparoscopic instruments. 相似文献
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Among the rare occurrences of primary malignant mesenchymal tumors of the liver, the development of liposarcoma has been only theoretically listed--there is no proven example in the literature. This article documents a case of primary liposarcoma of the liver in a 30-year-old woman who presented with a huge intrahepatic tumor in the left lobe measuring 14 X 10 X 6 cm. It was composed of two distinct macroscopic and histologic features--the well-differentiated liposarcoma and the cellular, nonlipogenic pleomorphic sarcoma. The former was a mature, lipomatous tumor with various stages of lipoblasts. The latter was much more cellular, made up of pleomorphic cells admixed with a few areas of spindle cells with many mitotic figures, resembling a pleomorphic variant of malignant fibrous histiocytoma. Oil red O stain revealed multifocal, but a scanty amount, of fat-storing tumor cells in both compartments aside from large fat globules in the differentiated area. This is the first reported case of primary liposarcoma of the liver. 相似文献
74.
The authors describe a case of idiopathic hypereosinophilic syndrome (HES) terminated as a T-cell lymphoma in a 3-year-old girl. The clinical course was chronic and characterized by chronic eczema, persistent peripheral blood eosinophilia, organomegaly, interstitial lung change, and pericarditis. Postmortem examination demonstrated a disseminated T-cell lymphoma involving the inguinal lymph node, liver, lung, and kidney. The findings of the current case suggest a possibility that certain abnormalities in this case of idiopathic HES per se may have triggered the development of malignant lymphoma, and it may represent a transition of idiopathic HES into a T-cell lymphoma. Other possible sequences are discussed. The development of T-cell malignancy in idiopathic HES in a girl is quite an unusual presentation. 相似文献
75.
Ethanol extract of Panax ginseng C. A. Meyer, which has been used for centuries as a tonic in Asian countries, exhibited a selective induction of epoxide hydratase and cytosolic glutathione transferase activity without the concurrent induction of aryl hydrocarbon hydroxylase activity. Thus, Panax ginseng appears to have the potential to alter the metabolic patterns of benzo(a)pyrene and its reactive metabolites. 相似文献
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79.
Su Jin Park Su Jin Kim Yumie Rhee Ji Hyun Byun Seong Hwan Kim Myoung Hee Kim Eun Jig Lee Sung-Kil Lim 《Journal of bone and mineral research》2007,22(6):889-896
The FIGNL1 gene was proven to be a new subfamily member of ATPases associated with diverse cellular activities (AAA proteins). In this in vitro study, the AAA proteins inhibited osteoblast proliferation and stimulated osteoblast differentiation. We showed that FIGNL1 may play some regulatory role in osteoblastogenesis. INTRODUCTION: The fidgetin-like 1 (FIGNL1) gene encodes a new subfamily member of ATPases associated with diverse cellular activities (AAA proteins). Although the FIGNL1 protein localizes to both the nucleus and cytoplasm, the function of FIGNL1 remains unknown. In a previous study, we identified several genes that mediate the anabolic effects of basic fibroblast growth factor (bFGF) on bone by using microarray data. FIGNL1 was one of the genes that downregulated >2-fold in MC3T3-E1 cells after treatment with bFGF. Therefore, this study was aimed to identify and confirm the function of FIGNL1 on osteoblastogenesis. MATERIALS AND METHODS: We examined the effect of the FIGNL1 gene on proliferation, differentiation, and apoptosis in mouse osteoblast cells (MC3T3-E1 and mouse primary calvarial cells) using flow cytometry, RT-PCR, cell proliferation assay, and cell death assay. MC3T3-E1 cells and mouse calvarial cells were transfected with small interfering RNA (siRNA) directed against the FIGNL1 or nontargeting control siRNA and examined by cell proliferation and cell death assays. Also, FIGNL1 was fused to enhance green fluorescent protein (EGFP), and the EGFP-fused protein was transiently expressed in MC3T3-E1 cells. RESULTS: Reduced expression of FIGNL1 by bFGF and TGF-beta1 treatment was verified by RT-PCR analysis. Overexpression of FIGNL1 reduced the proliferation of MC3T3-E1 and calvarial cells, more than the mock transfected control cells did. In contrast, siFIGNL1 transfection significantly increased the proliferation of osteoblasts, whereas overexpression of FIGNL1 did not seem to alter apoptosis in osteoblasts. Meanwhile, overexpression of FIGNL1 enhanced the mRNA expression of alkaline phosphatase (ALP) and osteocalcin (OCN) in osteoblasts. In contrast, siFIGNL1 decreased the expression of ALP and OCN. A pEGFP-FIGNL1 transfected into MCT3-E1 cells had an initially ubiquitous distribution and rapidly translocated to the nucleus 1 h after bFGF treatment. CONCLUSIONS: From these results, we proposed that FIGNL1, a subfamily member of the AAA family of proteins, might play some regulatory role in osteoblast proliferation and differentiation. Further analyses of FIGNL1 will be needed to better delineate the mechanisms contributing to the inhibition of proliferation and stimulation of osteoblast differentiation. 相似文献
80.