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81.
Foreign-body granulomas in the hand can appear secondary to an unrecognized foreign material. In a six-year-old boy, an extensive sterile osteitis of the second metacarpal bone appeared adjacent to a wood splinter. 相似文献
82.
Femke M van de Water Johanna M Boleij Janny G P Peters Frans G M Russel Rosalinde Masereeuw 《European journal of pharmaceutical sciences》2007,30(1):36-44
The activity of P-glycoprotein (Pgp/MDR1/ABCB1) and multidrug resistance proteins (MRP/ABCC) influence the pharmacokinetics and bioavailability of many drugs. Few suitable cell lines for the study of drug transport exist. Additional non-human cell lines may help clarify species differences and contribute to the current knowledge of drug transport. The aim of the present study was to characterize three rat epithelial cell lines for transporter expression and activity. Transporter expression was assessed in intestinal IEC-6 and renal GERP and NRK-52E cells using RT-PCR and Western blot analysis. Pgp and Mrp transport activity were analyzed by measuring calcein accumulation and glutathione-S-bimane efflux, respectively. The three cell lines showed Pgp expression and Pgp-dependent transport, both decreasing with culture time after reaching confluency. Besides Pgp, cells expressed Mrp1, Mrp3, Mrp4, and Mrp5, while Mrp2 and Mrp6 were absent. In addition, they showed temperature- and Mrp-dependent efflux of glutathione-S-bimane. Exposure to a panel of different inhibitors showed that this efflux was probably mediated by Mrp4. In conclusion, the three rat epithelial cell lines investigated showed Pgp and Mrp expression and transport. Mrp dependent transport was most likely mediated by Mrp4. In future, these cell lines may be used as in vitro models to study drug transport. 相似文献
83.
84.
K H Calhoun B R Peters C M Stiernberg F B Quinn 《Otolaryngology--head and neck surgery》1988,99(1):76-78
We report a metallic foreign body that entered through the anterior table of the frontal sinus, and rolled down to lodge in the nasofrontal duct. An electromagnet was used to remove the foreign body through a trephination. 相似文献
85.
The radiographic and histological morphology of 38 tumors lesions of the scapula are analyzed. Osteochondromas (n = 12), chondrosarcomas (n = 7), plasmacytomas (n = 4) and Ewing's sarcomas (n = 3) were the most frequent neoplasms. The radiographically determined growth rates allowed an estimate of the dignity in all cases. Benign lesions were only observed in the first five decades of life, and were mostly located in the scapular blade. Most tumors found in the acromion and in the glenoid region and all lesions diagnosed in the 6th to the 8th decades of life were malignant. In 63.2% of cases correct diagnosis of the type of lesion present was possible on radiographic examination. 相似文献
86.
87.
Another step forward towards improved outcome after HLA-haploidentical stem cell transplantation. 总被引:1,自引:0,他引:1
C Peters 《Leukemia》2004,18(11):1769-1771
88.
Reduction of epidural fibrosis in lumbar surgery with Oxiplex adhesion barriers of carboxymethylcellulose and polyethylene oxide. 总被引:5,自引:0,他引:5
Kathleen E Rodgers James T Robertson Theresa Espinoza Wilham Oppelt Stephanie Cortese Gere S diZerega Richard A Berg 《The spine journal》2003,3(4):277-83; discussion 284
BACKGROUND CONTEXT: Postsurgical epidural adhesions and fibrosis after surgery for lumbar disc herniation are a consequence of normal wound healing. The presence of fibrosis renders reoperations risky, and in some patients fibrosis may lead to nerve root tethering. PURPOSE: One approach to minimizing the risk of developing epidural adhesions is to provide a barrier between the dural membrane and the healing connective tissues. The purpose of these studies was to evaluate such a barrier device. STUDY DESIGN/SETTING: In vivo investigation in an animal model at a university laboratory. PATIENT SAMPLE: Rabbit. OUTCOME MEASURES: Gross and histomorphic evaluation. METHODS: Barriers comprised of carboxymethylcellulose (CMC) and polyethylene oxide (PEO) (Oxiplex; FzioMed, Inc., San Luis Obispo, CA) were studied as devices to reduce epidural adhesion formation in rabbit laminotomy and laminectomy models. The barriers tested were either a gel alone (gel) or a gel covered with a film (gel/film combination). Two laminotomy or laminectomy sites (depending on the surgical method) were created in each rabbit at L4 and L6. One site was treated with a CMC/PEO gel, or CMC/PEO gel/film combination, and the other site served as a surgical control. Two surgical models that differed in the extent of adhesion formation at untreated injury sites and the method of injury generation were used. RESULTS: Model A, which did not incorporate dural abrasion, resulted in up to 40% adhesion-free laminectomy sites in controls. Model B, which did incorporate abrasion of the dural membrane, resulted in less than 10% adhesion-free laminotomy sites in controls. Compositions of CMC/PEO gels (2.5% to 10% PEO) and films (22.5% PEO) were tested in both models. Efficacy parameters included measuring the number of sites free of epidural fibrosis and reduction in the severity of fibrosis (adhesions). Both gels and gel/film combinations consistently reduced the frequency and the extent of epidural fibrosis in both models. Gels of CMC/PEO containing a higher content of PEO (10%) and a higher molecular weight of PEO (4.4 mD) were most effective in Model B and resulted in up to 84% laminotomy sites with minimal or no epidural fibrosis, whereas controls exhibited over 90% of the sites with epidural fibrosis. Histological evaluation of the surgical sites indicated that the reduction of epidural fibrosis was accompanied by normal bone healing. In addition, these experiments demonstrated that the gel/film combination provided no additional benefit to that obtained by the gel alone. CONCLUSIONS: Gels of CMC/PEO reduced epidural fibrosis and did not impair normal heal ing. 相似文献
89.
Edward J. Ciaccio PhD Hiroshi Ashikaga MD PhD Riyaz A. Kaba MD Daniel Cervantes MD Bruce Hopenfeld PhD Andrew L. Wit PhD Nicholas S. Peters MD PhD Elliot R. McVeigh PhD Hasan Garan MD James Coromilas MD 《Heart rhythm》2007,4(8):1034-1045
BACKGROUND: Infarct border zone (IBZ) geometry likely affects inducibility and characteristics of postinfarction reentrant ventricular tachycardia, but the connection has not been established. OBJECTIVE: The purpose of this study was to determine characteristics of postinfarction ventricular tachycardia in the IBZ. METHODS: A geometric model describing the relationship between IBZ geometry and wavefront propagation in reentrant circuits was developed. Based on the formulation, slow conduction and block were expected to coincide with areas where IBZ thickness (T) is minimal and the local spatial gradient in thickness (DeltaT) is maximal, so that the degree of wavefront curvature rho proportional, variant DeltaT/T is maximal. Regions of fastest conduction velocity were predicted to coincide with areas of minimum DeltaT. In seven arrhythmogenic postinfarction canine heart experiments, tachycardia was induced by programmed stimulation, and activation maps were constructed from multichannel recordings. IBZ thickness was measured in excised hearts from histologic analysis or magnetic resonance imaging. Reentrant circuit properties were predicted from IBZ geometry and compared with ventricular activation maps after tachycardia induction. RESULTS: Mean IBZ thickness was 231 +/- 140 microm at the reentry isthmus and 1440 +/- 770 microm in the outer pathway (P <0.001). Mean curvature rho was 1.63 +/- 0.45 mm(-1) at functional block line locations, 0.71 +/- 0.18 mm(-1) at isthmus entrance-exit points, and 0.33 +/- 0.13 mm(-1) in the outer reentrant circuit pathway. The mean conduction velocity about the circuit during reentrant tachycardia was 0.32 +/- 0.04 mm/ms at entrance-exit points, 0.42 +/- 0.13 mm/ms for the entire outer pathway, and 0.64 +/- 0.16 mm/ms at outer pathway regions with minimum DeltaT. Model sensitivity and specificity to detect isthmus location was 75.0% and 97.2%. CONCLUSIONS: Reentrant circuit features as determined by activation mapping can be predicted on the basis of IBZ geometrical relationships. 相似文献
90.