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31.
This study examined the effects of client and therapist sex on client self-disclosure and improvement from individual psychotherapy. Based upon closing summary data collected at a college psychological counseling center, it was found that clients were more likely to be rated as low disclosers by female than by male therapists. Males viewed more clients as improved than did females (74% vs. 50%).  相似文献   
32.
Urodynamic pressure measurements using catheters have been widely used among clinicians. More often objective interpretation of urodynamic pressure measurements requires fundamental understanding of pressure measurement techniques due to many measurement artifacts. In this study we developed a simplified compound thick-walled cylinder model to investigate the mechanical nature of urodynamic pressure measurement as well as pressure transmission. Efficacy of collagen implantation was also explored. Lamé's formulation was used to find analytical solutions. Pressure transmission can be related to catheter caliber and the compressibility of the urethral tissue (poisson ratio) in a simple mathematical form. The theoretical pressure transmission ratio will be 133% with the additional incompressibility assumption, reflecting the passive structural transmission of intraabdominal pressure increase. The relationship between the pressure measurement error and the catheter caliber was found to be linear (r2 = 0.94 +/- 0.04) and two or more pressure measurements need to be used to find the uninstrumented pressure. It was predicted that collagen implantation treatment might improve the pressure transmission ratio maximally by 33%.  相似文献   
33.
Structural and electrical properties of 8 yttria stabilized zirconia (YSZ) ceramics doped with varying concentrations (0.5–2.0 wt%) of Mg2+ ions were investigated. The result from X‐ray diffraction indicates the formation of fully stabilized cubic phase. Scanning electron microscopy observation confirms the marginal decrease in grain size with addition and increase of MgO content. However, a concentration beyond x = 0.5 wt% results in segregation along the grain boundaries. Complex impedance diagrams showed an enhancement in the grain and grain boundary conductivities with doping of magnesium and are strongly dependent on its concentration. It is observed that among the compositions investigated, 8YSZMg0.5 exhibited higher conductivity at all temperatures (600–800 °C) with a maximum conductivity of 0.0345 S/cm at 800 °C. This is further confirmed by the lowest activation energy of Ea = 0.92 eV, estimated for 8YSZMg0.5 in comparison to 1–1.01 eV observed for other compositions. Comparative evaluation of these results with standard 8YSZ electrolytes reveals the possibility of the effective use of 8YSZMg0.5 as a new electrolyte material for intermediate temperature solid oxide fuel cell applications. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
34.
Laparoscopic surgery was performed on a 16 year-old female rhesus monkey presenting with chronic lethargy and inappetence. The procedure revealed a "napkin-ring" stricture located in the ascending large colon. Histologic evaluation of the colonic lesion exhibited large numbers of irregular acini lined by a single layer of well-differentiated neoplastic epithelial cells. Based on the gross and histopathologic findings a diagnosis of adenocarcinoma of the proximal colon was made.  相似文献   
35.
Patients with segmental bone and joint replacement prostheses because of tumors increasingly need revision surgery because of their long term survival. Between 1970 and 1990, 208 custom prosthetic replacements were performed for limb salvage in patients with tumors. Reoperations were required in 52 patients. The mean time to reoperation was 37 months. The reoperation procedures included 35 prosthetic revisions, 11 amputations, four arthrodeses, one vascularized fibular graft, and one open reduction and internal fixation of a fracture with supplemental bone graft. Functional assessment using the new Musculoskeletal Tumor Society scoring system was available for the 36 living patients, and their mean rating was 63% (18.9) at 12 years' mean followup. Of the 35 patients who received a new prosthesis, 12 (33%) patients needed a third operation at mean followup of 68 months. The probability of prosthetic survival in the group of 35 patients needing revision to the same or another prosthesis was 79% at 5 years and 65% at 10 years. The chance and frequency of needing reoperation increased as patients survived longer. Reoperations for tumor recurrence or infection usually resulted in amputation. Reoperation for failed initial segmental bone and joint prosthetic replacement is feasible and effective and can be done without jeopardizing subsequent patient and implant survival or without significantly affecting functional results compared with the values before reoperation.  相似文献   
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Surface expression of the T cell antigen receptor (TCR) in mature T cells requires the association of a variable heterodimer (alpha.beta or gamma.delta) with six invariant CD3 polypeptides (gamma, delta, epsilon-epsilon, zeta-zeta, or zeta-eta). We described here that deletion of the cytoplasmic tail polypeptide sequence (Lys-Lys-Lys-Asn-Ser) of TCR beta-chain (beta CT) results in expression of the truncated beta-chain on the surface of a mature T cell hybridoma line, in the absence of TCR-alpha, as a glycophosphatidylinositol (GPI)-anchored monomeric polypeptide. The GPI-anchored TCR-beta CT is not associated with CD3-epsilon and is incapable of conventional signal transduction. Association with TCR-alpha prevents beta CT from GPI-linkage formation. The alpha beta CT heterodimer binds the CD3 polypeptides, and the resultant TCR alpha beta CT/CD3 complex is capable of signal transduction. Our data show that a signal sequence for GPI-linkage formation is present in TCR-beta, and this alternative membrane anchoring mechanism can be utilized by beta-chain polypeptide lacking the CT sequence. We conclude therefore that in the absence of TCR-alpha expression, the beta-chain CT sequence plays an essential function in hindering GPI-linkage formation, thereby preventing escape of incompletely assembled TCR beta-chain to the cell surface of mature T cells.  相似文献   
39.
Bilateral lesions in the most posterodorsal aspects of the amygdala in female rats resulted in immediate and dramatic weight gains on a standard lab chow diet. The rate of weight gain returned to normal by Day 20, but the difference in body weight between animals with amygdaloid lesions and those with sham lesions was maintained for the duration of the study (60 days). Because rats with posterodorsal amygdaloid lesions have also been found to be hyperinsulinemic, it is hypothesized that the lesions result in a similar, though smaller, version of the syndrome that follows lesions of the ventromedial hypothalamus.  相似文献   
40.
Many antitumor agents and antibiotics affect cells by interacting with type II topoisomerases, stabilizing a covalent enzyme-DNA complex. A pathway of recombination can apparently repair this DNA damage. In this study, transposon mutagenesis was used to identify possible components of the repair pathway in bacteriophage T4. Substantial increases in sensitivity to the antitumor agent m-AMSA [4'-(9-acridinylamino)methanesulfon-m-anisidide] were found with transposon insertion mutations that inactivate any of six T4-encoded proteins: UvsY (DNA synaptase accessory protein), UvsW (unknown function), Rnh (RNase H and 5' to 3' DNA exonuclease), alpha-gt (alpha-glucosyl transferase), gp47.1 (uncharacterized), and NrdB (beta subunit of ribonucleotide reductase). The role of the rnh gene in drug sensitivity was further characterized. First, an in-frame rnh deletion mutation was constructed and analyzed, providing evidence that the absence of Rnh protein causes hypersensitivity to m-AMSA. Second, the m-AMSA sensitivity of the rnh-deletion mutant was shown to require a drug-sensitive T4 topoisomerase. Third, analysis of double mutants suggested that uvsW and rnh mutations impair a common step in the recombinational repair pathway for m-AMSA-induced damage. Finally, the rnh-deletion mutant was found to be hypersensitive to UV, implicating Rnh in recombinational repair of UV-induced damage.  相似文献   
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