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21.
Large amplitude vibrations of Mindlin plates are studies using Lagrangian, isoparametric, quadrilateral elements with selective integration. Square, rectangular, circular and elliptical plates with clamped and simply supported boundary conditions are considered.  相似文献   
22.
Thermal buckling analysis of circular plates with localized axisymmetric damages has been carried out using the finite element method. The damages are characterized as degradation in material properties locally. Thermal buckling load parameters are evaluated for both simply supported and clamped circular plates with varying locations, magnitudes and lengths of damage. Numerical results are presented for different cases, and trends in variations of load parameters are discussed.  相似文献   
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Stability of moderately thick rectangular plates is studied in this paper. A high precision triangular finite element is used in the present formulation. Explicit expressions for elastic stiffness and geometric stiffness matrices are presented; the use of numerical integration is avoided. The effect of transverse shear on the critical loads is brought out through two typical examples.  相似文献   
25.
Pyothorax-associated lymphoma is known to develop in patients who received an artificial pneumothorax for pulmonary tuberculosis some 30 to 40 years previously. Such patients exhibit large, immunoblastic lymphoma cells and often have a B-cell phenotype. We present a patient with an artificial pneumothorax and such a late developing lymphoma but with the unique finding of aberrant T- and B-cell phenotypes. Southern blot hybridization using immunoglobulin gene JH and T-cell receptor beta chain receptors revealed germline configurations. Lymphomas developing in immunocompromised patients, such as those with acquired immunodeficiency syndrome, may show such unusual phenotypes. The unusual phenotypes found in this patient provide evidence that his pyothorax-associated lymphoma was related to an immunocompromised state.  相似文献   
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The menstrual and premenstrual experiences of black Zimbabwean women were examined. Twenty-five professional women and twenty-five domestic workers were interviewed using semistructured, open-ended interviews designed to explore their experiences. An analysis of consensual data indicated a number of predominant themes, including secrecy associated with menstruation, the negativity surrounding menarche, the breakdown of the traditional family network that passes on information about menstruation, and the acceptance of menstrual cycle experiences by the women. The main differences between the two groups concerned explanations of the functions and purpose of menstruation and the reporting of physical and affective symptoms. These differences are suggestive of the impact of educational level on experiences of menstruation.  相似文献   
28.
Accumulating evidence shows that the repertoire of major histocompatibility complex class I-restricted epitopes extends beyond conventional translation reading frames. Previously, we reported that scanthrough translation, where the initiating AUG of a primary open reading frame is bypassed, is most likely to account for the presentation of cryptic epitopes from alternative reading frames within the influenza A PR/8/34 nucleoprotein gene. Here, we confirm and extend these findings using an epitope cassette construct that features two well-defined CD8(+) T cell (TCD8+) epitopes in alternative reading frames, each preceded by a single start codon. Expression of one epitope depends on scanning of the ribosome over the first AUG with translation initiation occurring at the second AUG. We find that scanthrough translation has great potency in our system, with its impact being modulated, as predicted, by the base composition surrounding the first initiation codon, the number of start codons preceding the point of alternate reading frame initiation, and the efficiency with which the epitope itself is generated. Additionally, we investigated the efficiency of eukaryotic translation termination codons, to assess codon readthrough as a mechanism for cryptic epitope expression from 3' untranslated regions. In contrast with initiation codons, eukaryotic stop codons appear to be highly efficient at preventing expression of epitopes encoded in 3' untranslated regions, suggesting that 3' untranslated regions are not a common source of cryptic epitope substrate. We conclude that scanthrough is a powerful mechanism for the expression of epitopes encoded in upstream alternative open reading frames that may contribute significantly to TCD8+ responses and to tolerance induction.  相似文献   
29.
Alpha adrenergic blocker has become the first choice in the medical treatment of benign prostatic hyperplasia (BPH). The efficacy of alpha adrenergic blocker has been suggested to be related to the prostatic tissue components, and to be ineffective in treating the clinical symptoms caused by BPH in some cases. The efficacy and prostate reduction of an anti-androgenic agent, chlormadinone acetate, combined with alpha adrenergic blocker, tamsulosin hydrochloride, were evaluated using 40-BPH patients insufficiently treated with tamsulosin hydrochloride alone. Fifty mg of chlormadinone acetate and 0.2 mg of tamsulosin hydrochloride were administered orally once a day for 16 weeks to patients with a prostate subjective symptoms score, I-PSS, of greater than 13 or a peak flow rate of less than 12 ml/s, even after the treatment with 0.2 mg of tamsulosin hydrochloride alone for more than four weeks. Total I-PSS decreased significantly after four weeks. The total irritative symptom score did not change for 16 weeks, but the total obstructive symptom score decreased significantly, as did the total I-PSS. In objective data, the estimated volume of both total prostate and the transition zone on transrectal ultrasonogram decreased significantly at the end of the treatment, and the peak flow rate decreased significantly after 12 weeks. These findings suggest that the addition of chlormadinone acetate may be a reasonable alternative in the treatment of BPH patients responding insufficiently to tamsulosin hydrochloride alone, and that combination therapy using chlormadinone acetate and tamsulosin hydrochloride may be useful for BPH patients with serious obstructive symptoms.  相似文献   
30.
The short arm of chromosome 17 is one of the most frequently affected chromosomal regions in lung cancers, while there is solid evidence that the p53 gene at 17p13.1 is a target for frequent 17p deletions. In the present study, we re-evaluated 17p deletions in lung cancers by conducting a detailed analysis of the minimum deleted region(s) on 17p with reference to the p53 gene status in each 100 primary lung cancer cases. In addition to the p53 locus at 17p13.1, the presence of an independent, commonly deleted region(s) at 17p13.3 was identified. Furthermore, loss of heterozygosity (LOH) at 17p13.3 was shown to be even more frequent than that at 17p13.1 and it appeared to occur in the absence of p53 mutation and/or 17p13.1 deletion. These results suggest that in addition to the p53 gene at 17p13.1, an as yet unidentified tumor suppressor gene(s) residing at 17p13.3 might play a role in lung carcinogenesis possibly in an earlier phase than the p53 gene. This would warrant future studies to identify the putative tumor suppressor gene at 17p13.3 in order to gain a better understanding of the molecular pathogenesis of this fatal disease.  相似文献   
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