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1.
Transport of hydrogen in elastic metals has been analysed in terms of an impedance-like non-linear transfer function (TF). The equilibrium in a membrane specimen is perturbed by a sinusoidal signal of the concentration of hydrogen, of large amplitude, applied to one of its surfaces. The fundamental harmonics of periodically reproducible flux at the same surface is considered as a response. The TF is defined as the ratio of the signal to the response. The power of the said TF in determining the diffusion coefficient of hydrogen in a metal–hydrogen system and its bulk elastic modulus was analysed for the example of α-phase Pd–H and Pd81Pt19–H systems. It has been found that such a TF is suitable for determination of the above parameters. Also, the sensitivity of these estimates to the uncertainty of concentration of hydrogen in the metal, its partial molar volume and the thickness of the specimen has been explored.  相似文献   
2.
We have reported the case of a 73-year-old woman with a posterior shoulder dislocation and comminuted fracture of the proximal humerus occurring during a seizure. Surgery disclosed an acute humeral fracture superimposed on a chronically dislocated humeral head. Endoprosthetic replacement yielded a satisfactory clinical result. We found no similar report in the literature.  相似文献   
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BACKGROUND: Many patients with asthma have an IgE-mediated allergic component to the disease. Omalizumab, a monoclonal anti-IgE antibody, has demonstrated clinical efficacy in patients with allergic asthma. The effects of omalizumab on inflammation in asthma are not completely understood. OBJECTIVES: To evaluate the effects of omalizumab on allergen- and growth factor-stimulated proinflammatory cytokine and nitric oxide (NO) production in human bronchial epithelial cells (BECs) and to compare them to the effects of budesonide, a corticosteroid with known anti-inflammatory properties. METHODS: Human BECs were stimulated in duplicate with interleukin 1beta (IL-1beta), 100 U/mL; ragweed, 10 microg/mL; dust mite, 1000 AU; and epithelial growth factor, 40 ng/mL; and either 10(-7) M budesonide or 0.1 microg/mL of omalizumab in a 4% dust mite atopic serum medium for 6 and 24 hours in 5% carbon dioxide at 37 degrees C. Tumor necrosis factor alpha and transforming growth factor betaexpression and production and IL-4, IL-13, and NO production were assayed using gene-specific messenger RNA or sensitive enzyme-linked immunosorbent assays. RESULTS: Omalizumab inhibited the expression and of production proinflammatory cytokines and growth factor in antigen-stimulated BECs at 6 and 24 hours. Production of NO was inhibited at 6 hours and increased at 24 hours by omalizumab and budesonide. CONCLUSIONS: The effects of omalizumab were similar to those of budesonide. These results, consistent with previously reported evidence of anti-inflammatory effects of omalizumab, demonstrate that omalizumab may reduce airway inflammation and probably contributes to decreased airway remodeling in patients with asthma.  相似文献   
5.
The aim of this paper is an analysis of clinical documentation and results of autopsy of 21 patients (pts) who died of invasive aspergillosis (IA) in the Institute of Tuberculosis and Chest Diseases in years 1993-2000 and the assessment of predisposing factors for IA. In 17 pts IA was the main and in other 4 only an accessory cause of death. All pts were treated with corticosteroids and/or cytostatic drugs--because of lung cancer (11 pts), cancer in other site (2 pts), haematologic disorders (2 pts), Wegener's granulomatosis (1 pt), polymyositis (1 pt), idiopathic pulmonary fibrosis (1 pt) and other diseases (3 pts). In 15 out of 21 pts granulocytopenia was revealed (from 0.008 x 10(9)/L to 0.82 x 10(9)/L) on an average one month before death. In 15 pts IA was limited to the lungs, in 6 others there were also fungal lesions in brain, kidneys, liver, spleen and heart. Pts with disseminated form of IA had significantly lower granulocyte count and were treated with higher doses of corticosteroids than others. Immunosuppressive drugs and granulocytopenia can be regarded as predisposing factors. Fatal course of IA depended also on the late diagnosis.  相似文献   
6.
The aim of this study was to assess how the extent of the number and percentage of lymphocytes in BALF and also the CD4 to CD8 ratio can help to predict the short outcome in sarcoidosis. Material consisted of 74 patients, 39 men and 35 women in the age from 23 to 58 years. 11 patients had chest lesions in stage I, 43 in stage II and 20 in stage III. Clinical markers of activity (fever, erythema nodosum) were present in 22 cases. Extrathoracic lesion were present in 31 and abnormal pulmonary function in 30. In all patients BAL was done before treatment and lymphocyte count, percentage and CD4/CD8 ratio was calculated. 50 patients were treated with corticosteroids and 24 were observed without treatment. After 6-12 month of observation regression of sarcoid lesions was observed in 46 of 50 patients treated with corticosteroids and in 17 out of 24 patients observed without treatment. There were no differences in lymphocyte count and percentage in BALF and in the short term outcome between group treated with corticosteroids and without treatment. The patients in whom regression of lesions was observed have however significantly higher CD4/CD8 ratio than others.  相似文献   
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Functional bracing for the treatment of fractures of the humeral diaphysis   总被引:11,自引:0,他引:11  
BACKGROUND: Nonoperatively treated fractures of the humeral diaphysis have a high rate of union with good functional results. However, there are clinical situations in which operative treatment is more appropriate, and, though interest in plate osteosynthesis has decreased, intramedullary nailing has gained popularity in recent years. We report the results of treating fractures of the humeral diaphysis with a prefabricated brace that permits full motion of all joints and progressive use of the injured extremity. METHODS: Between 1978 and 1990, 922 patients who had a fracture of the humeral diaphysis were treated with a prefabricated brace that permitted motion of adjacent joints. The injured extremities were initially stabilized in an above-the-elbow cast or a coaptation splint for an average of nine days (range, zero to thirty-five days) prior to the application of the prefabricated brace. Orthopaedic residents, supervised by teaching staff, provided follow-up care in a special outpatient clinic. Radiographs were made at each follow-up visit until the fracture healed. RESULTS: We were able to follow 620 (67 percent) of the 922 patients. Four hundred and sixty-five (75 percent) of the fractures were closed, and 155 (25 percent) were open. Nine patients (6 percent) who had an open fracture and seven (less than 2 percent) who had a closed fracture had a nonunion after bracing. In 87 percent of the 565 patients for whom anteroposterior radiographs were available, the fracture healed in less than 16 degrees of varus angulation, and in 81 percent of the 546 for whom lateral radiographs were available, it healed in less than 16 degrees of anterior angulation. At the time of brace removal, 98 percent of the patients had limitation of shoulder motion of 25 degrees or less. We were unable to follow most of the patients long-term, as they did not return to the clinic once the fracture had united and use of the brace had been discontinued. CONCLUSIONS: Functional bracing for the treatment of fractures of the humeral diaphysis is associated with a high rate of union, particularly when used for closed fractures. The residual angular deformities are usually functionally and aesthetically acceptable. The present study illustrates the difficulties encountered in carrying out long-term follow-up of indigent patients treated in charity hospitals that are affiliated with teaching institutions. These difficulties are also becoming common with patients insured under managed-care organizations and are frequent in our peripatetic population.  相似文献   
9.
Transepithelial photorefractive keratectomy (tPRK), where both the epithelium and stroma are removed in a single-step, is a relatively new procedure of laser refractive error correction. This study compares the 3-month results of myopia and compound myopic astigmatism correction by tPRK or conventional alcohol-assisted PRK (aaPRK).This prospective, nonrandomized, case–control study recruited 148 consecutive patients; 93 underwent tPRK (173 eyes) and 55 aaPRK (103 eyes). Refractive results, predictability, safety, and efficacy were evaluated during the 3-month follow-up. The main outcome measures were uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and mean refractive spherical equivalent (MRSE).Mean preoperative MRSE was −4.30 ± 1.72 D and −4.33 ± 1.96 D, respectively (P = 0.87). The 3-month follow-up rate was 82.1% in the tPRK group (n = 145) and 86.4% in aaPRK group (n = 90), P = 0.81. Postoperative UDVA was 20/20 or better in 97% and 94% of eyes, respectively (P = 0.45). In the tPRK and aaPRK groups, respectively, 13% and 21% of eyes lost 1 line of CDVA, and 30% and 31% gained 1 or 2 lines (P = 0.48). Mean postoperative MRSE was −0.14 ± 0.26 D in the tPRK group and −0.12 ± 0.20 D in the aaPRK group (P = 0.9). The correlation between attempted versus achieved MRSE was equally high in both groups.Single-step transepithelial PRK and conventional PRK provide very similar results 3 months postoperatively. These procedures are predictable, effective, and safe for correction of myopia and compound myopic astigmatism.  相似文献   
10.
Zeitschrift für Herz-,Thorax- und Gefäßchirurgie - Die Lungentransplantation hat einen souveränen Stellenwert in der Therapie schwerer therapierefraktärer...  相似文献   
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