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101.
102.
Uveal melanoma: correlation of histopathologic and radiologic findings by using thin-section MR imaging with a surface coil 总被引:1,自引:0,他引:1
Lemke AJ Hosten N Bornfeld N Bechrakis NE Schüler A Richter M Stroszczynski C Felix R 《Radiology》1999,210(3):775-783
PURPOSE: To evaluate whether the different signal intensities at magnetic resonance (MR) imaging of melanoma are associated with a higher content of melanin. MATERIALS AND METHODS: In a prospective study, MR imaging and ophthalmoscopic examination findings in 42 patients (19 women, 23 men; age range, 30-87 years) with uveal melanoma were compared with histopathologic examination findings obtained after enucleation. MR imaging was performed with 2-mm sections by using a 5-cm surface coil. T1- and T2-weighted images were obtained before and after contrast material administration. RESULTS: In 33 (79%) of the patients, there was homogeneous tumor pigmentation, whereas in nine (21%) patients, there was inhomogeneous bipartite tumor pigmentation. Compared with the histopathologic data, the results of qualitative evaluation were accurate in 29 (58%) of 50 and in 26 (53%) of 49 tumorous areas on T1- and T2-weighted images, respectively. Quantitative evaluation yielded better results, especially at T1-weighted imaging; an 86% correlation was found. Because of methodological reasons, only the superficial pigmentation of inhomogeneous tumors could be evaluated with ophthalmoscopy. CONCLUSION: Thin-section MR imaging of the eye enables an accurate prediction of melanomatous pigmentation with quantitative evaluation of plain T1-weighted images and is superior to ophthalmoscopy in cases of inhomogeneous pigmentation. 相似文献
103.
Fehrenbach A Wittwer T Cornelius J Ochs M Fehrenbach H Wahlers T Richter J 《The Journal of surgical research》1999,82(2):285-293
Ischemia/reperfusion-induced increase in pulmonary microvascular permeability was shown to be reduced after preservation with Celsior. We investigated reimplantation-induced lung injury in isolated, reperfused rat lungs after preservation via the pulmonary artery with Celsior, Celsior + prostacyclin, and reduced-potassium (40 mmol) Euro-Collins solution (40 ml/kg/body wt each) followed by 2 h of cold ischemia. Arterial and veneous oxygen tensions were recorded during 50 min of in vitro reperfusion after which the lungs (10 right lungs per experimental group) were fixed by vascular perfusion. The tissue was further processed for microscopy, and histological changes were quantified stereologically. Lung preservation with Celsior resulted in a significantly higher volume of air-filled alveolar space with a large proportion of widely distended alveoli compared with the other groups. In the Euro-Collins group the fraction of atelectatic alveoli exceeded that observed in Celsior-preserved lungs. In accordance, the difference between arterial and venous oxygen tensions was significant among Euro-Collins- and Celsior-protected lungs, with improved oxygenation values in the Celsior group. In contrast, addition of prostacyclin to Celsior treatment resulted in rather variable structural as well as functional data. There were no differences in the volumes of intraalveolar edema among the groups tested. However, the volume of alveolar tissue was increased in the Euro-Collins group. In conclusion, compared with Euro-Collins and Celsior + prostacyclin solutions, preservation with Celsior resulted in improved structural characteristics which in combination with improved oxygenation parameters supports the prospective advantage of Celsior in clinical organ preservation. 相似文献
104.
Whole-cell Na+ currents (INa) were recorded in inspiratory neurons in a medullary slice preparation from neonatal mouse that contains the functional respiratory network. Hypoxia and metabolic poisoning with KCN rapidly inhibited INa by reducing the number of Na+ channels available for opening during depolarization. Application of agents specific for G-proteins, protein kinase C and A, intracellular Ca2+ and pH did not prevent the hypoxic inhibition of INa. The effects of hypo-osmolarity and hypoxia were additive, whereas hyperosmolarity partially prevented a subsequent hypoxic inhibition of INa. Cytochalasin B and colchicine decreased, and taxol or phalloidin increased INa and reduced its hypoxic inhibition. We conclude that cytoskeleton rearrangements during hypoxia are responsible for suppression of a fast INa in brainstem respiratory neurons, which could be mediated by the uncoupling of channel inactivation gates from cytoskeletal elements. 相似文献
105.
PROBLEM: Spinal stenosis is a common and increasing problem in the elderly population and a diagnostic and therapeutic challenge. METHODS: An overview of etiology, epidemiology, diagnostics and therapy is given based on a literature review of the years 1978-1998 and experiences since 1985. RESULTS: Dealing with spinal stenosis we have to distinguish concerning diagnostics and therapy between cervical and lumbar spinal stenosis. The cardinal symptom of the lumbar spinal stenosis is the claudicatio spinalis and of the cervical spinal stenosis the cervical myelopathy occasionally combined with radiculopathy. The first therapeutic step should be the conservative therapy in nearly all cases, the only exception is a severe cervical myelopathy where an operation is indicated. In case of persistent or progressive symptoms under a sufficient conservative therapy, operative therapy is indicated. The different possible therapy decisions will be based on flow-charts. CONCLUSION: Whereas in lumbar spinal stenosis the indication for operative therapy should be considered with reservation, in cervical spinal stenosis with myelopathy operative therapy should be considered at an early stage. 相似文献
106.
J. E. Richter T. O. G. Kovacs P. A. Greski-Rose B. Huang & R. Fisher 《Alimentary pharmacology & therapeutics》1999,13(6):795-804
BACKGROUND: This randomized, double-blind, multicentre study compared lansoprazole with placebo for symptomatic relief of patients with non-erosive gastro-oesophageal reflux disease (GERD). METHODS: 214 patients with symptomatic, non-erosive GERD (moderate to severe daytime and/or night-time heartburn greater than half the days over the past 6 months and during the 7- to 10-day pre-treatment period) were randomized to either lansoprazole 15 mg or lansoprazole 30 mg, or placebo o.d. for 8 weeks. RESULTS: Daily diary data indicated that on the first treatment day a statistically significantly smaller percentage of lansoprazole patients reported daytime and night-time heartburn and antacid usage, compared with placebo patients. Lansoprazole patients also reported statistically significant less severe daytime and night-time heartburn on the first treatment day. During 0-4, 4-8, and 0-8 weeks of therapy, a statistically significant smaller percentage of days and nights with heartburn, less severe daytime and night-time heartburn, and less antacid usage were observed in the lansoprazole group compared to the placebo group. The percentages of patients with adverse reactions were similar in the lansoprazole and placebo groups. CONCLUSIONS: The results of this study demonstrate that lansoprazole is an appropriate therapy for patients with symptomatic non-erosive GERD. 相似文献
107.
The official drug Sennae folium (obtained from Cassia angustifolia and/or C. acutifolia) was found to contain small amounts of volatiles (0.047% based on dry weight) which were analyzed in detail by GC and GC/MS. More than 200 compounds could be detected, 122 of them were identified, representing about 90.7% of the peak area of the total mixture. The volatile constituents can be classified into monoterpenoids (8.8% for sample A and 34.6% for B), sesquiterpenoids (4.2% and 4.0%, respectively), phenylpropanoids (4.2%/15.2%), fatty acids and esters (54.3%/14.2%), and miscellaneous compounds (19.3%/22.7%). Apart from hexadecanoic acid which was strong in both samples (36.8%/9.7%), the occurrence of menthol, geranylacetone, and (E)-anethole is of interest. 相似文献
108.
Gabor F Haberl I Wirth M Richter K Theyer G Baumgartner G Wenzl E Hamilton G 《International journal of oncology》1996,9(3):527-531
The pseudoautosomal encoded MIC2 glycoprotein is a tumor-associated antigen of Ewing's sarcoma (ES) and closely related tumors of unknown function. To investigate the use of this protein as selective drug carrier recombinant MIC2 was coupled to doxorubicin by a two step glutaraldehyde method (molar ratio DOX/MIC2 of 32 and 16). The conjugates showed dose-dependent cytostatic activity against the ES cell line SK-ES1, the peripheral neuroectodermal line KAL and the prostate cancer cell line PC-3 concurrent with reduced toxicity against normal lymphoblasts. In comparison to free doxorubicin the MIC2-doxorubicin conjugates exhibited highest activity against the PC-3 cell line. Confocal microscopy showed intracellular accumulation of MIC2 conjugates. 相似文献
109.
Stoskopf CH Richter DL Ciesla JR Baker SL 《Journal of health and human services administration》1996,19(1):79-98
South Carolina's HIV/AIDS community long-term care Medicaid (Section 2179) waiver is evaluated via cost comparison and patient satisfaction measures. The waiver offers personal care aids, adult day care, counseling, home meals, hospice, private-duty nursing, and foster care supervision in addition to regular Medicaid services. Services to 111 eligible individuals and 52 individuals pending eligibility are evaluated by five methods. A cost comparison is conducted by comparing the cost per patient eligible day of the waiver recipients with those of a comparable group of HIV/AIDS Medicaid patients who did not participate in the waiver. The waiver services are shown to cost less than services delivered to comparable recipients. Costs per patient eligible day were $35.68 and $68.56 for the waiver patients and non-waiver patients, respectively. Telephone surveys, focus groups, provider compliance reviews, and patient record reviews were used to assess patient satisfaction and quality of care. Waiver patients were satisfied with the program overall and with the service managers who are responsible for coordinating services. Problems are identified with personal care aid performance and TB testing for health care providers. A shortage of dentists willing to see waiver patients and delays in the eligibility process are also identified. In spite of small problems, the South Carolina's HIV/AIDS community long-term care Medicaid waiver program is considered a success. 相似文献
110.
The cytochemistry, surface markers and functional properties of purified mononuclear cells obtained from the peripheral blood and spleen of a patient with leukemic reticuloendotheliosis were studied. Nonspecific esterase activity, a monocyte marker, was demonstrable in 83% of the peripheral blood mononuclear cells and 84% of the splenic mononuclear cells. Rosetting techniques failed to detect T or B lymphocyte surface markers on the majority of the cells. Direct immunofluorescence revealed capped, noncytophilic surface immunoglobulin on the cells with all immunoglobulin classes being detectable. Since noncapping conditions ahd been used during immunofluorescence staining, the observed caps were attributed to in vivo binding of autoantibodies to the "hairy" cells. This conclusion was supported by the demonstration of susceptibility of the "hairy" cells to lysis mediated by normal allogeneic lymphocytes. It is postulated that the "hairy" cells in this patient are leukemic monocytes which bear autoantibodies directed against leukemia associated antigens. 相似文献