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71.
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73.
Ultrasonographic (US), computed tomographic (CT), and magnetic resonance imaging (MRI) findings of a patient suffering from an amebic abscess of the liver complicated by a bronchohepatic fistula are presented. Subsequent to US, CT provided the specific diagnosis. Multiplanar MRI was valuable to directly visualize the secondary diaphragmatic rupture and the bronchohepatic fistula.  相似文献   
74.
In 50 partially edentulous patients, 133 (48 maxillary; 85 mandibular) Astra Tech dental implants of 2 different surface textures (machined; TiO‐blasted) were alternately installed, supporting 52 fixed partial dentures (FPDs). Before abutment connection 2 machined implants (1 mandibular; 1 maxillary) were found to be non-osseointegrated and were replaced. Another implant could not be restored due to a technical complication. Two FPDs were remade because of technical complications, both because of abutment fractures. Thus, after 2 years in function, the cumulative survival rates were 97.7% and 95.7% for implants and prostheses, respectively. There was no statistically significant difference in survival rate between the 2 types of implants, 100%(TiO‐blasted) vs 95.3%(machined), P =0.24. After 2 years in function, when both jaw and type of implants were combined, the mean (SD) marginal bone loss was 0.24 (0.69) mm. No statistically significant difference in bone loss was found between the 2 tvues of implant after 2 years of loading, 0.04 (0.82) mm, P >0.30.  相似文献   
75.
During the 10-year period 1981-1990, 1, 199 patients in the county of South Jutland, Denmark, had 1, 477 primary total hip arthroplasties (THA) performed because of primary arthrosis (OA).

The patients were followed until the end of 1994, with a mean follow-up of 5.6 (0-14) years. Bilateral operations were performed on 356 patients, whereas 248 patients had died with only 1 THA.

The cumulated risk of replacement of the contralateral hip was approximately 0.15 1 year after replacement of the first hip, 0.20 after 2 years, 0.29 after 5 years and 0.47 after 10 years, respectively.

During the follow-up period, the demand for a THA of the contralateral hip continued to be approximately 15 times higher than in the general population.  相似文献   
76.
Summary. The impact of valvular, myocardial and pericardial abnormalities on cardiac haemodynamics in patients treated for Hodgkin's disease with COPP/ABVD with and without mediastinal irradiation was determined in 49 patients 2–10 years after induction therapy. Diagnostic procedures to evaluate cardiac function consisted of history, physical examination, exercise bicycle stress test, M-mode two-dimensional and pulsed Doppler echocardiography. No patient reported symptoms related to cardiomyopathy, and only one of the 49 had evidence of coronary heart disease. Pericardial thickening was seen on echocardiograms in 19/49 patients (38.8%), valvular thickening in 21/49 (42·9%), and reduced fractional shortening in 9/49 (18·4%). The Doppler-derived mean E and A (±SD) of transmitral flow were 0·75 ± 0·14 m/s and 0·56 ± 0·09 m/s, respectively, in patients receiving chemotherapy and 0·81 ± 0.19 m/s and 0·63 ± 0·20 m/s in those with additional mediastinal irradiation. There was no statistically significant difference between mean E and A in transmitral flow in patients treated for Hodgkin's disease and control subjects. Furthermore, the transtricuspid and hepatic vein flow velocities did not differ significantly. Although the present study demonstrates high frequencies of pericardial and valvular thickening in patients treated for Hodgkin's disease with the COPP/ABVD regimen with or without mediastinal irradiation, it showed no impact on cardiac flow velocities. The abnormalities might thus be of minor clinical relevance in these patients.  相似文献   
77.
Background and Objective: Flashlamp pumped dye (FPDL), Q-switched Nd:YAG, and alexandrite lasers are the most clinically used laser lithotriptors. Although calculi are fragmented by laser induced mechanical stresses for all lithotriptors, different fragment sizes and fragmentation efficiencies have been reported. In this work the effect of the pulse duration and pulse shape on the fragmentation processes is studied. Material and Methods: Fragmentation processes are characterized on model stones and on sensing target fibers. Stone fragmentation and cavitation bubble generation are observed by video flash photography. Shock wave occurrence and strength are monitored with an hydrophone. Results: For the FPDL, stone fragmentation is induced by the collapse of the large cavitation bubble formed. For the Q-switched Nd:YAG, fragmentation is already observed during the laser pulse, at the plasma onset, although further fragmentation can occur at the bubble collapse. For pulse durations corresponding to the alexandrite, an intermediate fragmentation regime is observed. Conclusion: For the first time the physical basis of the observed differences in the fragmentation efficiencies of current laser lithotriptors is described. For nanosecond durations the fragmentation processes are governed by plasma induced shock waves. On the contrary, for microsecond durations fragmentation is governed by cavitation. The high fragmentation efficiency of microsecond lasers is due to a high laser energy transfer into cavitation. © 1995 Wiley-Liss, Inc.  相似文献   
78.
Mechanism of the CuCl/O2-mediated Oxygenation of Naphtholes The mechanism of the oxygenation of 1- and 2-naphthole derivatives in the system $\left[ {\mathop {\rm C}\limits^{+} \mathop {\rm u}\limits^{1} {\rm L}_4 } \right]^{+} + {\rm O}_2 \rightleftharpoons \left[ {\mathop {\rm C}\limits^{+} \mathop {\rm u}\limits^2 {\rm L}_3 {\rm O}_2^{^.} } \right]^{+} + {\rm L}$ depending on solvent (L) and temp., is studied. It was possible to distinguish between reactions via the radical ion pair type (L = CH3CN) and hydrogen abstraction via free radicals (L = CH3OH). There is a marked difference between the oxygen transfer to the naphthole derivatives and the oxygenation of 2, 6-di-tert.-butylphenol ( 6 ), which does not depend characteristically on L and temp.  相似文献   
79.
Endothelial selectins are crucial for the recruitment of leukocytes into sites of inflammation. On T cells, ligands for selectins become induced upon differentiation into the effector/memory stage. Initial in vitro studies suggested a correlation between the Th1 phenotype and ligand expression, but whether this also holds true in vivo remained uncertain. We here analyzed selectin ligands on CD4+ T cells producing IFN-gamma, IL-4 or IL-10, prototypic cytokines of the Th1, Th2 and Tr1 subset, respectively. We analyzed mice infected with influenza virus, the bacterium Listeria, and the parasites Toxoplasma (all Th1 models) or Nippostrongylus (Th2 model). A link between the Th1 phenotype and ligand expression was not found in vivo. Surprisingly, the potentially regulatory IL-10-producing T cells displayed the highest frequency of ligand-positive cells in general. Within the inflamed tissues, the frequencies of P-selectin-binding cells increased in the dominant subset, either Th1 or Th2. Up-regulation was also found for E-selectin ligands during influenza, but not Nippostrongylus infection. In conclusion, conditions driving T cell polarization into either Th1 or Th2 in vivo do not affect the expression of selectin ligands, but acquisition of P-selectin binding and hence migration into inflamed tissues is boosted by an inflammatory milieu.  相似文献   
80.
We studied vascular endothelial growth factor (VEGF) expression in bone marrow sections obtained from 3 healthy donors and 41 patients with acute myeloid leukemia (AML) of various French-American-British (FAB) subtypes by immunohistochemical analysis using an anti-VEGF antibody. In normal bone marrow, the anti-VEGF antibody reacted with myeloid progenitor cells and megakaryocytes but not with erythroid cells or mature granulocytic cells. High levels of VEGF were found in the bone marrow in patients with AML-M1, -M2, -M3, -M4, -M4Eo, and -M5. In these leukemias, the vast majority of myeloblasts (> 90%) expressed VEGF. By contrast, in AML-M0, the percentage of VEGF-positive blasts was lower in most cases (median, 42%), and if at all detectable, these blast cells contained only trace amounts of VEGF. In AML-M3 and -M4Eo, maturing granulocytes failed to express VEGF similar to granulocytes in normal bone marrow. In AML-M6, myeloblasts exhibited VEGF, whereas erythroid cells did not. In AML-M7, blast cells and megakaryocytes were identified as major sources of VEGF. In summary, VEGF expression in the bone marrow is restricted to certain stages of differentiation and maturation of myeloid cells and correlates with the FAB category.  相似文献   
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