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951.
Petersen W Beske C Stein V Laprell H 《Archives of orthopaedic and trauma surgery》2002,122(4):235-236
We report the case of a 29-year-old patient with an uncommon handgun accident. A gun was resting in his pocket when an accidental shot was fired. The projectile penetrated the skin of the thigh, travelled through the quadriceps muscle and entered the articular cavity at the upper pole of the suprapatellar recess. It passed the femoropatellar joint space and stopped within the infra-articular fad pad. The bullet was localized by conventional X-rays and removed by arthroscopy. The patient developed no infection, and in a clinical follow-up examination 6 months postoperatively, we observed no pathological findings. 相似文献
952.
Schriever S Mistry-Burchardi N Grabein B Näbauer M Siebold C Hoops JP Klauss V 《Klinische Monatsbl?tter für Augenheilkunde》2002,219(3):164-167
BACKGROUND: Immunosuppressed patients occasionally suffer from a multifocal infection with Nocardia. It is important to distinguish Nocardia farcinica from Nocardia asteroides, because of different sensitivity against antibiotics. PATIENT AND METHODS: A 40-year-old patient with polycystic renal disease successfully underwent a kidney transplantation without complications. Immunosuppression consisted of: corticosteroids, azathioprin and ciclosporin A. Ten weeks later he developed acute choroiditis with consecutive retinal detachment and neovascular glaucoma in one eye. In addition, 14 weeks after transplantation CT scans revealed multiple cerebral abscesses. RESULTS: In the course of the disease Nocardia farcinica (N. f.) was identified by cerebral stereotactic biopsy of a cerebral lesion, histological examination of the enucleated globe and sputum culture. Histologically filamentous, eosinophilic organisms were found. Microbiology identified aerobic actinomycetes in cultures and Nocardia farcinica by PCR. Therapeutically the combination of vancomycin, ampicillin, and sulbactam was successful. CONCLUSION: In immunosuppressed patients Nocardia farcinica can become life-threatening. One of the first manifestations may be a choroiditis. Infection of the respiratory tract followed by hematogenous spread is the common way of systemic nocardiosis. Biopsy followed by identification of species by PCR is recommended because of the specific therapeutic strategies associated with each species. 相似文献
953.
Deuter CM Schlote T Hahn GA Bende T Derse M 《Klinische Monatsbl?tter für Augenheilkunde》2002,219(3):138-142
BACKGROUND: In clinical practice ophthalmologists often need a tonometer which is independent of a slit lamp. Such a hand-held device is the Tono-Pen. We compared the precision of two equal Tono-Pens with Goldmann applanation tonometry. MATERIAL AND METHODS: Measurement of intraocular pressure (IOP) was done in 100 eyes of 51 patients (mean age 63 +/- 15 years) suffering from ocular hypertension or glaucoma. According to a random table either the right or left eye was measured using Goldmann tonometer first and the Tono-Pen second. For the other eye the measurement was reversed. One of the two equal Tono-Pens (Solan/USA) was used according to a second random table. Three measurements were obtained with each instrument on both eyes within 15 minutes subsequently. Patients were placed in an upright position for all measurements. RESULTS: Even for well-trained ophthalmologists a learning curve of approximately 10 measurements was observed using the Tono-Pen. The Tono-Pen measured an average IOP of 16.9 mm Hg in all 100 eyes. The Goldmann tonometer measured an average IOP of 17.7 mm Hg. The difference was not statistically significant. The standard deviation for all measurements was better for the Tono-Pen (4.7 mm Hg vs 5.8 mm Hg for Goldmann tonometer). No reduction of the IOP after Tono-Pen measurement was observed (in contrast to the Goldmann tonometer). The reproducibility of the Tono-Pen on the same eye was inferior to the Goldmann tonometer by a factor of 2. There was an almost significant difference in reproducibility between two equal Tono-Pens. CONCLUSIONS: Measurement of IOP with the Tono-Pen is comparable to Goldmann applanation tonometry if an average of 3 measurements is used. The difference between two equal Tono-Pens indicates the need for improvement of the quality check during production. 相似文献
954.
Congenital and acquired nystagmus, particularly pendular and jerk nystagmus, see-saw nystagmus and spasmus nutans, may be the presenting sign of a suprasellar mass lesion.(1) The large variety of different suprasellar mass lesions requiring quite different therapeutic measures necessitates exact histological diagnosis for optimal therapeutic strategy planning.(2) Stereotactic tumor biopsy has become a well-established diagnostic approach, combining minimal surgical trauma with a high degree of diagnostic safety. Particularly in the two most frequent suprasellar mass lesions - craniopharyngiomas and pilocytic astrocytomas - accurately planned stereotactic drainage of tumor cysts combined with radiotherapy and/or stereotactic radiosurgery allows successful decompression and tumor control as well as maximum preservation of visual and endocrinological functions when compared with conventional surgical procedures.(2-11) 相似文献
955.
Background
Xanthurenic acid is an endogenous product of tryptophan degradation by indoleamine 2,3-dioxygenase (IDO). We have previously reported that IDO is present in mammalian lenses, and xanthurenic acid is accumulated in the lenses with aging. Here, we studied the involvement of xanthurenic acid in the human lens epithelial cell physiology.Methods
Human lens epithelial cells primary cultures were used. Control cells, and cells in the presence of xanthurenic acid grow in the dark. Western blot analysis and immunofluorescence studies were performed.Results
In the presence of xanthurenic acid human lens epithelial cells undergo apoptosis-like cell death. In the control cells gelsolin stained the perinuclear region, whereas in the presence of 10 μM xanthurenic acid gelsolin is translocated to the cytoskeleton, but does not lead to cytoskeleton breakdown. In the same condition caspase-3 activation, and DNA fragmentation was observed. At low (5 to 10 μM) of xanthurenic acid concentration, the elongation of the cytoskeleton was associated with migration of mitochondria and cytochrome c release. At higher concentrations xanthurenic acid (20 μM and 40 μM) damaged mitochondria were observed in the perinuclear region, and nuclear DNA cleavage was observed. We observed an induction of calpain Lp 82 and an increase of free Ca2+ in the cells in a xanthurenic acid concentration-dependent manner.Conclusions
The results show that xanthurenic acid accumulation in human lens epithelial cells disturbs the normal cell physiology and leads to a cascade of pathological events. Xanthurenic acid induces calpain Lp82 and caspases in the cells growing in the dark and can be involved in senile cataract development. 相似文献956.
Morphometric changes of the choriocapillaris and the choroidal vasculature in eyes with advanced glaucomatous changes 总被引:2,自引:0,他引:2
PURPOSE: In addition to an elevated intraocular pressure a compromise of the ocular blood supply have been implicated in the pathogenesis of primary open-angle glaucoma. The purpose of this study was to quantify morphologic changes in the choroid including choriocapillaris thickness and density and diameter of large choroidal vessels in post mortem eyes with advanced primary open-angle glaucoma. METHODS: We analyzed 20 eye bank eyes (provided from the Georgia Eye Bank in Atlanta) with end stage primary open-angle glaucoma and compared them with 20 age-matched control eye bank eyes. The eyes were processed for light microscopy and following variables were measured with a digital filar micrometer: density and diameter of large choroidal vessels in the macular and equatorial choroid; thickness of the choroid in the macular and equatorial region; density and thickness of choriocapillaris in the macular, peripapillary, and equatorial choroid; and peripapillary capillary-free area nasal and temporal to the optic disk. RESULTS: Eyes with glaucoma displayed a lower density of the capillaries of the choriocapillaris as compared to control eyes in the macular, temporal peripapillary, and equatorial choroid with 0.50-0.55 (p=0.018), 0.46-0.51 (p=0.016), and 0.50-0.55 (p=0.038), respectively. There was no significant difference for the choriocapillaris density in the nasal peripapillary choroid, the thickness of the capillaries of the choriocapillaris in all assessed locations, and the nasal and temporal peripapillary capillary-free zone of the choriocapillaris between eyes with glaucomatous damage and controls. Assessment of large choroidal vessels in the macular choroid showed that eyes with glaucoma had a decreased density of veins (11.7-38.9 mm(-2); p<0.001) and arteries (7.7-12.4 mm(-2); p=0.005) and arteries with a higher diameter (45.6-28.2 microm; p<0.001) as compared to control eyes. The large vessels in the equatorial choroid displayed no significant difference in diameter but a lower density (21.2-44.1 mm(-2); p=0.017) in eyes with glaucomatous damage as compared to controls. CONCLUSION: Eyes with advanced glaucomatous damage after long standing primary open-angle glaucoma exhibit several changes including decreased density of capillaries of the choriocapillaris and decreased density of large choroidal vessels. We cannot conclude from our study whether the observed vascular changes in the choroid are primary pathogenic factors or secondary phenomena. 相似文献
957.
Human Caco-2 cells have been established as a model system for intestinal biotransformation and permeability. When grown on Transwell polycarbonate filters they develop morphologic and biochemical characteristics of enterocytes with well separated apical and basolateral surfaces. In addition, Caco-2/TC-7 cells have proven to be useful to study regulation of human UDP-glucuronosyltransferases (UGTs) by Ah receptor agonists and antioxidant-type inducers such as beta-naphthoflavone (BNF) and t-butylhydroquinone (TBHQ). In the present investigation, formation and transport of 4-methylumbelliferone glucuronide was studied in intact Caco-2 cell monolayers. The following results were obtained: when loaded with 50-200 microM MUF either apically or basolaterally, MUF-GA was the major metabolite which was mostly released (80%) at the basolateral surface, probably via the multidrug resistance protein isoform MRP3; MUF sulfate formation was low (5 +/-2%). Pretreatment of cells with 80 microM TBHQ or 50 microM BNF for 72 hr before addition of 100 microM MUF enhanced basolateral secretion of MUF-GA 1.4- and 1.7-fold, respectively. However, at >200 microM MUF, MUF-GA secretion and induction was smaller, probably due to inhibition of intracellular UGT activity. MRP3 protein was localized to the basolateral surface of Caco-2 cells but was not induced by TBHQ or BNF. The results suggest that MUF-GA is mostly secreted basolaterally in Caco-2 cell monolayers. Treatment with TBHQ or BNF significantly enhanced MUF-GA formation in the intact cell. 相似文献
958.
Pseudohypericin (PH) and hypericin (H) are photosensitizing plant pigments from Hypericum perforatum. H displays cytotoxic and apoptosis-inducing effects in neoplastic cell lines. Here, we have assessed the phototoxic and apoptosis-inducing capacity of PH compared to H in a cell culture model with human leukemic lymphoma cells (Jurkat). Treatment with both photoactivated H and PH resulted in a dose-dependent inhibition of cell proliferation, whereas not photoactivated H and PH had no effect at the concentrations tested. The half-maximal inhibitory concentration (IC50) of H was lower (100 ng/mL) as compared to PH (200 ng/mL) (p < 0.05). In an apoptosis assay we found a dose-dependent increase of DNA fragmentation after treatment with both photoactivated H and PH. The cytotoxic potential of PH should be taken into account during systemic therapy with Hypericum extracts, since PH is about two times more abundant than H in Hypericum perforatum. 相似文献
959.
960.