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51.
Lerman Caryn; Gold Karen; Audrain Janet; Lin Ting Hsiang; Boyd Neal R.; Orleans C. Tracy; Wilfond Ben; Louben Greg; Caporaso Neil 《Canadian Metallurgical Quarterly》1997,16(1):87
In this article the authors report on the short-term impact of incorporating biomarker feedback about exposure and genetic susceptibility into minimal-contact quit-smoking counseling (QSC). Four hundred and twenty-seven smokers were randomized to 1 of 3 treatments: (a) QSC, (b) QSC + exposure biomarker feedback (EBF) about carbon monoxide in exhaled breath, or (b) QSC + EBF + biomarker feedback about genetic susceptibility to lung cancer (SBF). We observed significant immediate positive effects of SBF, compared with EBF and QSC, on perceived risk, perceived quitting benefits, and fear arousal. However, at the 2-month follow-up, there were no group differences in quit rates. SBF did lead to significant reductions in the number of cigarettes smoked for smokers who were in the preparation stage. Smokers in the EBF and QSC conditions showed reductions in depressive symptoms by 2 months, but smokers in the SBF condition did not. In the context of QSC, genetic feedback may heighten vulnerability and possibly promote distress, but may not immediately enhance quitting in most smokers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
The goal of this research was to identify patients' preferences for physician inquiry into various aspects of health status and to examine whether the preconsultation availability of health status data (collected from the SF-36 Health Status Questionnaire) influenced the physician's conduct during the consultation. Results from 58 prenatal patient visits yielded the following findings. First, patients expressed strong preferences for physicians to ask about the patient's perceptions of health in general and about physical dimensions of health status such as pain, vitality, and role limitations due to physical functioning. Patients also were more satisfied when doctors were perceived as having asked about these issues. Second, patients varied considerably in their preferences for physician inquiries into psychosocial issues such as social functioning, mental health, and role limitations due to emotional problems. Approximately half the patients wanted these matters discussed, whereas the remainder either did not care or preferred that doctors not ask about these topics. Third, the preconsultation availability of health status information had little effect on the degree to which physicians asked about the patient's health-related quality of life. Clinical implications are discussed. 相似文献
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54.
The purpose of this review is to summarize recent functional and structural findings regarding non-collagenous matrix proteins in bone and teeth, to compare gene locations for bone and tooth matrix proteins with loci for hereditary skeletal diseases, and to present several provocative hypotheses which integrate this new information into a physiological context. Hypothesis I proposes that the molecular composition of rapidly deposited and mineralized woven bone, as well as the responsiveness of cells synthesizing woven bone to stimuli, is different from that for more slowly synthesized lamellar bone, implying the existence of distinctive osteogenic mechanisms. This review of recent research strongly supports this proposal. Briefly, the protein composition of woven bone matrix is enriched in acidic phosphoproteins BAG-75 and BSP, which are not expressed in lamellar bone, which is itself enriched in osteocalcin. De novo deposition and mineralization of woven bone occurs faster than in lamellar bone by means of a matrix-vesicle-assisted mechanism. Deposition of woven bone occurs at sites experiencing biomechanical strains higher than those experienced by lamellar bone. In addition, woven bone in metaphyseal regions is more susceptible to osteoclastic resorption after space flight, ovariectomy, and loss of weightbearing than is lamellar bone. Finally, osteoprogenitor cells responsive to parathyroid hormone reside in the metaphyseal region of long bones. Taken together, these findings suggest that Hypothesis I represents a useful paradigm for future studies. Specific functions mediated by most individual bone and tooth matrix proteins remain uncertain. A review of current literature suggests that the functionality of skeletal matrix proteins is expressed through specific binding sites composed of particular species-conserved structural motifs (Hypothesis 2). Examples include the previously recognized Asp-Ser-Ser motif of dentin phosphophoryns and the gamma-carboxyglutamic acid motif of matrix GLA protein and osteocalcin. A new polyacidic amino acid motif composed of consecutive Asp and Glu residues (n > 7) was defined in extracellular matrix components osteopontin, bone sialoprotein, and bone acidic glycoprotein-75 on the basis of strong functional analogies with similar polyacidic stretches in divalent metal storage proteins of the endoplasmic reticulum and sarcoplasmic reticulum. These structural motifs represent prime targets for future structure-function studies in vivo and in vitro. 相似文献
55.
Epidemiology of and risk factors for pancreatic cancer 总被引:1,自引:0,他引:1
In the United States, incidence of and mortality from pancreatic cancer increased for several decades earlier in this century but have tended to level off in recent years. Rates increase with age and are higher in blacks than in whites and higher in men than in women. Cigarette smoking increases the risk of pancreatic cancer, while alcohol consumption largely shows no relationship, coffee consumption shows little, if any, association, and a number of occupational exposures seem to be associated but the results are not fully consistent. Finally, human studies have suggested positive associations with meat consumption and carbohydrate intake and a protective effect of dietary fiber and consumption of fruits and vegetables. Thus, much progress has been made in the last two decades in identifying risk factors, but much epidemiologic work is needed to identify and reduce putative exposures. 相似文献
56.
TE Goldberg EF Torrey JM Gold LB Bigelow RD Ragland E Taylor DR Weinberger 《Canadian Metallurgical Quarterly》1995,17(1):77-84
We investigated the effect of the adenosine receptor agonist 5'-(N-ethylcarboxamido)adenosine (NECA) in catecholamine secretion from adrenal chromaffin cells that exhibit only the A2b subtype adenosine receptor. NECA reduced catecholamine release evoked by the nicotinic agonist 1,1-dimethyl-4-phenylpiperazinium (DMPP) in a time-dependent manner. Inhibition reached 25% after 30-40-min exposure to NECA. This effect on DMPP-evoked catecholamine secretion was mirrored by a similar (27.7 +/- 3.3%), slowly developing inhibition of [Ca2+]i transients induced by DMPP that peaked at 30-min preincubation with NECA. The capacity of the chromaffin cells to buffer Ca2+ load was not affected by the treatment with NECA. Short-term treatment with NECA failed both to modify [Ca2+]i levels and to increase endogenous diacylglycerol production, showing that NECA does not activate the intracellular Ca2+/protein kinase C signaling pathway. The inhibitory effects of NECA were accompanied by a 30% increase of protein phosphatase activity in chromaffin cell cytosol. We suggest that dephosphorylation of a protein involved in DMPP-evoked Ca2+ influx pathway (e.g., L-type Ca2+ channels) could be the mechanism of the inhibitory action of adenosine receptor stimulation on catecholamine secretion from adrenal chromaffin cells. 相似文献
57.
58.
Logi Vidarsson Charles Cunningham Garry E Gold John M Pauly 《IEEE transactions on medical imaging》2007,26(7):981-989
The purpose of this work was to present and evaluate a new method for directly designing T2-selective preparation pulses. Using a modified Shinnar-Le-Roux (SLR) transform, the design of T2-selective pulses becomes equivalent to designing a pair of polynomials one of which represents the longitudinal magnetization and the other the transverse magnetization. The polynomials enable one to directly analyze the various tradeoffs involved in the design. To evaluate the new method, a short-T2-selective magnetization preparation pulse was designed. Following the preparation pulse, a 2D Fourier transform (2DFT) multislice gradient echo sequence was used for imaging. For verification Bloch equation simulations were performed along with both in vivo and phantom scans. Phantom scans showed good signal suppression of long-T2 species. This is supported by good long-T2 signal suppression seen on the in vivo images. Simulations indicate that the pulse is robust to +/-150 Hz B0 inhomogeneities and +/-10% B1 inhomogeneities. 相似文献
59.
HU Baer H Friess M Abou-Shady P Berberat A Zimmermann LI Gold M Korc MW Büchler 《Canadian Metallurgical Quarterly》1998,10(12):1031-1039
BACKGROUND: Transforming growth factor betas (TGF-betas) are a group of homologous polypeptides that exert pleiotropic effects on various cell types and stimulate the formation of extracellular matrix and fibrosis. To evaluate whether TGF-beta isoforms (TGF-beta1, TGF-beta2 and TGF-beta3) and their receptors (types I-III) are also of importance in the pathophysiology of liver cirrhosis, we analysed their concomitant expression and localization in human liver cirrhosis. PATIENTS: Cirrhotic liver tissue samples were obtained from 17 patients (four women, 13 men) with a median age of 41 years (range 22-67). Normal liver tissues from ten patients (seven women, three men) with a median age of 55 years (range 45-75) served as controls. METHODS: The tissues were fixed in Bouin's solution and paraffin-embedded for histological analysis. For RNA analysis, freshly obtained tissue samples were snap-frozen in liquid nitrogen and stored at -80 degrees C until analysed. Northern blot analysis was used to examine the expression of TGF-beta1, beta2 and beta3 and their receptors, type I (TbetaR-I), type II (TbetaR-II) and type III (TbetaR-III). Immunohistochemistry was performed to determine the localization of the corresponding proteins in the normal and the cirrhotic liver. RESULTS: Northern blot analysis revealed enhanced expression (P < 0.05) of TGF-beta1 (twofold increase), TGF-beta2 (threefold increase) and TGF-beta3 (8.5-fold increase) and of TbetaR-II (threefold increase) mRNA in liver cirrhosis in comparison with normal controls. In contrast, TbetaR-I (ALK-5) and TbetaR-III mRNA expression showed no significant changes. No TGF-beta isoform immunoreactivity was present in hepatocytes in either normal livers or in liver cirrhosis. However, in liver cirrhosis, intense TGF-beta1 immunoreactivity was present in bile duct and ductular epithelial cells (including ductular proliferations) and in inflammatory cells. In a few sinusoidal lining cells, faint TGF-beta1 and moderate TGF-beta2 immunoreactivity was present. TGF-beta3 immunostaining was present in bile duct and ductular epithelial cells, in inflammatory cells and in fibroblast-like spindle cells in liver cirrhosis. For TbetaR-I and TbetaR-II, the immunoreactivity was localized in hepatocytes and biliary cells in normal and cirrhotic liver tissues, with higher intensity for TbetaR-II in the cirrhotic liver. CONCLUSION: Enhanced expression of all three TGF-bea isoforms and of TbetaR-II in liver cirrhosis suggests their involvement in this fibrotic disorder. The higher immunoreactivity of the three TGF-beta isoforms in the bile duct epithelial cells in cirrhotic tissues suggests a possible role of these cells in the pathogenesis of liver cirrhosis. 相似文献
60.
This article focuses on the difficulties facing the neophyte trainee in the field of psychotherapy. Three areas of such difficulties are identified, defined, and discussed: feelings of inadequacy and incompetence, anxieties concerning supervisors, and confusion concerning multiple theoretical views of clinical work. Two vignettes from the early training of the paper's junior authors illustrate and discuss these problems and their resolution in applied contexts. A conclusion is offered which emphasizes the value of supervisory recognition of these dimensions of trainees' experience, as well as their potential for modeling processes of growth that are likely to help supervisees' patients as well. 相似文献