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901.
Mechanoregulation of human articular chondrocyte aggrecan and type II collagen expression by intermittent hydrostatic pressure in vitro. 总被引:6,自引:0,他引:6
902.
903.
904.
Dorota Gabry's Annegret Dörfler Ala Yaromina Franziska Hessel Mechthild Krause Reinhard Oertel Prof. Dr. Michael Baumann 《Strahlentherapie und Onkologie》2008,184(1):48-53
PURPOSE: To evaluate the effect of lovastatin alone or combined with radiation on U87MG and FaDu cells in vitro and U87MG tumors in vivo. MATERIAL AND METHODS: Cell number, p21(WAF1) expression, apoptosis, reproductive cell death, and cell-cycle distribution were investigated after incubation of U87MG and FaDu cells in vitro. The effect of lovastatin (50 mg/kg/day) on tumor growth and on tumor growth delay after single-dose irradiation with 20 Gy was investigated using U87MG tumors in nude mice. RESULTS: Lovastatin dose dependently decreased cell number and proliferation of U87MG and FaDu cells. The proportion of cells in G0/G1 phase, apoptosis and p21 protein expression increased after lovastatin alone or combined with 4-Gy irradiation in both cell lines. Effects of lovastatin on cell cycle and cell number were more pronounced in U87MG compared to FaDu. No radiosensitization of clonogenic cells by lovastatin could be demonstrated in both cells lines, but the colony-forming ability after lovastatin alone was decreased in FaDu cells. In vivo, lovastatin decreased tumor volume over time but did not increase growth delay after irradiation of U87MG tumors with 20 Gy. CONCLUSION: The data support effects of lovastatin on proliferation, apoptosis and colony-forming ability in vitro and tumor volume in vivo. At the drug concentration achievable, lovastatin did not improve the effects of radiation on U87MG tumors in vivo. 相似文献
905.
Michael C. Cheung Eduardo A. Perez Manuel A. Molina Xiaoling Jin Juan C. Gutierrez Dido Franceschi Alan S. Livingstone Leonidas G. Koniaris 《Journal of gastrointestinal surgery》2008,12(4):731-738
Objective The objective of the study was to determine the outcomes for primary gastrointestinal melanomas (PGIM).
Material and methods The Surveillance, Epidemiology, and End Results database (1973–2004) was queried.
Results Overall, 659 cases of PGIM were identified. The annual incidence of PGIM was approximately 0.47 cases per million in 2000.
Overall median survival time was 17 months. Tumors were identified in the oral–nasopharynx (32.8%), anal canal (31.4%), rectum
(22.2%), esophagus (5.9%), stomach (2.7%), small bowel (2.3%), gallbladder (1.4%), and large bowel (0.9%). Univariate analysis
demonstrated age, tumor location, stage, surgery, and lymph node status were significant predictors of improved survival.
MST has not been reached for tumors located in the large bowel, while tumors located in the stomach demonstrated the shortest
median survival (5 months). Improvement in MST was observed for those patients undergoing surgical resection. The presence
of lymph node involvement conferred a poorer prognosis. Multivariate analysis of the cohort identified that location, advanced
tumor stage, failure to undertake surgical resection, positive lymph node status, and age were all independent predictors
of poorer outcome.
Conclusion PGIM occurs most often in the oral–nasopharynx and anal canal. Surgical extirpation is the only identifiable treatment modality
that significantly improves survival. 相似文献
906.
Michael Leonard Uthman Alao Aaron Glynn Mark Dolan 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2009,19(8):553-558
Between 1999 and 2005, we treated 41 patients with a total hip arthroplasty for failed fixation of a hip fracture. This study
had three purposes: (1) to determine the reason/s for fixation failure (2) to record difficulties/complications encountered
in converting to a salvage arthroplasty and (3) to compare the outcome of these patients (Group 1) with a matched group of
patients who underwent a primary hip arthroplasty (Group 2). Failure to achieve a good reduction and optimal screw placement
was evident in 80% of cases of failed fixation. A high incidence of complications was recorded in the perioperative period
during conversion to a salvage arthroplasty. Functional outcome was statistically inferior in Group1; this group also had
a higher incidence of complications. Radiographs at 2 years postoperatively showed evidence of femoral stem loosening in 16%
of the salvage group compared with 3% in the primary hip arthroplasty group. 相似文献
907.
908.
Small-animal PET of tumor angiogenesis using a (76)Br-labeled human recombinant antibody fragment to the ED-B domain of fibronectin. 总被引:2,自引:0,他引:2
Raffaella Rossin Dietmar Berndorff Matthias Friebe Ludger M Dinkelborg Michael J Welch 《Journal of nuclear medicine》2007,48(7):1172-1179
The aim of this study was to image the extra domain B (ED-B) of fibronectin, an angiogenesis-related target, in solid tumors using small-animal PET. Toward this aim, an ED-B fibronectin-binding human antibody derivative (L19-SIP) was labeled with (76)Br via an enzymatic approach. Biodistribution and imaging studies were performed in human teratoma-bearing mice for up to 48 h after injection. METHODS: L19-SIP was labeled with (76)Br using bromoperoxidase/H(2)O(2). The stability of the labeled antibody was tested both in vitro and in vivo. Biodistribution and small-animal imaging studies (PET and CT) were performed in F9-bearing 129/sv mice (n = 3 or 4). RESULTS: The enzymatic radiobromination approach afforded the labeled antibody in high yield (>55%) under mild reaction conditions. (76)Br-L19-SIP stability in mouse serum proved to be similar to that of the (125)I-labeled analog (>80% of intact material at 48 h after injection). Fast and specific in vivo targeting was obtained in tumors and other organs expressing ED-B fibronectin (i.e., ovaries and uterus). However, slow renal clearance and persistent activity predominately in blood and stomach suggests partial (76)Br-L19-SIP debromination in vivo. This debromination was confirmed in a metabolism study in normal mice. The F9 tumors were clearly imaged by small-animal PET at each considered time point, starting at 5 h up to 48 h after injection. CONCLUSION: (76)Br-L19-SIP specifically accumulated at the target site, enabling detailed small-animal PET of tumor neovasculature. Therefore, targeting the angiogenesis-associated expression of ED-B fibronectin can be a valuable tool for tumor detection using molecular imaging with PET. 相似文献
909.
Michael J. Gardner MD Sreevathsa Boraiah MD Keith D. Hentel MD David L. Helfet MD Dean G. Lorich MD 《The Journal of foot and ankle surgery》2007,46(4):256-260
Various patterns of ankle fractures that are not accounted for by common classification systems have been the subject of case reports. The first difficulty with these variant patterns is recognizing all associated pathology, followed by the successful application of stable fixation. The purpose of this study was to describe the common morphologic features and ligamentous injuries of a unique variant fracture pattern, as well as the surgical treatment technique and the short-term functional and radiographic outcomes. Of 121 consecutive unstable ankle fractures over a 2-year period, 7 patients were found to have a similar constellation of injuries around the ankle. A vertical shear fracture of the posteromedial tibial rim was the main feature. Six of the 7 also had a fracture of the posterior malleolus. On magnetic resonance imaging, the deltoid and posterior tibiofibular ligaments were intact in all cases. Fractures were treated with open anatomic reduction of the posteromedial and posterior fragments with antiglide plate fixation. All fractures healed at 2 months without loss of reduction, fixation failure, or surgical complications. The average American Academy of Orthopaedic Surgeons lower extremity score was 79 at an average of 8 months' follow-up. The common radiographic and morphologic features associated with this posteromedial fracture indicate that it likely occurs through a common mechanism that involves hyperplantarflexion. The characteristics of this fracture pattern have not been fully described previously, but this ankle fracture variant may occur in up to 6% of cases. Unstable ankle fractures should be evaluated carefully for evidence of posteromedial involvement so appropriate treatment may proceed. 相似文献
910.
Matt G Kushner Suck Won Kim Christopher Donahue Paul Thuras David Adson Michael Kotlyar James McCabe Jillian Peterson Edna B Foa 《Neuropsychopharmacology》2007,62(8):835-838
BACKGROUND: D-cycloserine (DCS), a glutamatergic partial N-methyl-d-aspartate (NMDA) agonist, can facilitate extinction learning related to cued fear in animals and humans. We predicted that DCS would accelerate obsession-related distress reduction in patients with obsessive-compulsive disorder (OCD) undergoing extinction-based exposure therapy. METHODS: We administered DCS (125 mg) or placebo in a double-blind fashion to individuals with OCD approximately 2 hours before each exposure session. RESULTS: D-cycloserine decreased both the number of exposure sessions required to achieve clinical milestones and the rate of therapy dropout. After four exposure sessions, patients in the DCS group reported significantly greater decreases in obsession-related distress compared with the placebo group; however, after additional sessions, the placebo group tended to catch up. CONCLUSIONS: D-cycloserine augmentation has the potential to increase the efficiency, palatability, and overall effectiveness of standard exposure therapy for OCD. 相似文献