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31.
The synthesis and evaluation of analogues of previously reported farnesyltransferase inhibitors, pyridyl benzyl ether 3 and pyridylbenzylamine 4, are described. Substitution of 3 at the 5-position of the core aryl ring resulted in inhibitors of equal or less potency against the enzyme and decreased efficacy in a cellular assay against Ras processing by the enzyme. Substitution of 4 at the benzyl nitrogen yielded 26, which showed improved efficacy and potency and yet presented a poor pharmacokinetic profile. Further modification afforded 30, which demonstrated a dramatically improved pharmacokinetic profile. Compounds 26 and 29 demonstrated significant in vivo efficacy in nude mice inoculated with MiaPaCa-2, a human pancreatic tumor-derived cell line.  相似文献   
32.
This study investigated the High Risk Model of Threat Perception (HRMTP) in middle-aged, urban chronic pain patients who had been referred to a secondary pain clinic after failing to respond to standard medical management. Relationships among absorption, social desirability (SD), and negative (e.g., depressive or anxious) affect were studied in 24 male and 73 female patients, (age range 22-88 years). Subjects completed the Tellegen Absorption Scale, the Marlowe-Crowne Social Desirability Scale, the Beck Depression Inventory--Second Edition, and the Beck Anxiety Inventory. The sample was significantly higher in SD and lower in absorption than normative groups. High SD patients endorsed significantly fewer items related to depression than those with low SD, but reported anxious ideation at about the same rate. These findings lend credence to the concept of chronic pain as a transduction of depressive, but not anxious, affect into somatic symptoms.  相似文献   
33.
PURPOSE: This study evaluated a cancer consultation preparation package (CCPP) designed to facilitate patient involvement in the oncology consultation. PATIENTS AND METHODS: A total of 164 cancer patients (67% response rate) were randomly assigned to receive the CCPP or a control booklet at least 48 hours before their first oncology appointment. The CCPP included a question prompt sheet, booklets on clinical decision making and patient rights, and an introduction to the clinic. The control booklet contained only the introduction to the clinic. Physicians were blinded to which intervention patients received. Patients completed questionnaires immediately after the consultation and 1 month later. Consultations were audiotaped, transcribed verbatim, and coded. RESULTS: All but one patient read the information. Before the consultation, intervention patients were significantly more anxious than were controls (mean, 42 v 38; P = .04); however anxiety was equivalent at follow-up. The CCPP was reported as being significantly more useful to family members than the control booklet (P = .004). Patients receiving the intervention asked significantly more questions (11 v seven questions; P = .005), tended to interrupt the physician more (1.01 v 0.71 interruptions; P = .08), and challenged information significantly more often (twice v once; P = .05). Patients receiving the CCPP were less likely to achieve their preferred decision making style (22%) than were controls (35%; P = .06). CONCLUSION: This CCPP influences patients' consultation behavior and does not increase anxiety in the long-term. However, this intervention, without physician endorsement, reduced the percentage of patients whose preferred involvement in decision making was achieved.  相似文献   
34.
Combination high dose rate brachytherapy (HDRB) and external beam radiation therapy is technically and clinically feasible as definitive treatment for localized prostate cancer. We report the first large Australian experience using this technique of radiation dose escalation in 82 patients with intermediate‐ and high‐risk disease. With a median follow up of 3 years (156 weeks), complications were low and overall prostate‐specific antigen progression‐free survival was 91% using the American Society for Therapeutic Radiology and Oncology consensus definition. The delivery of hypofractionated radiation through the HDRB component shortens overall treatment time and is both biologically and logistically advantageous. As a radiation boost strategy, HDRB is easy to learn and could be introduced into most facilities with brachytherapy capability.  相似文献   
35.
Objectives: A prospective study comparing the efficiacy and side-effects of oral sulindac with intravenous indomethacin in clinically stable preterm infants (<1750 g) requiring non-invasive closure of haemodynamically significant patent ductus arteriosus.
Methodology: As maturity and birthweight are the two major determinants of ductal closure, infants were matched as closely as possible for these parameters. An eligible patient was first assigned to the sulindac group and a subsequent patient with similar gestational age (± 1 week) and birthweight (±100 g) to the previously recruited infant would automatically receive indomethacin. A total of eight infants were enrolled in each group.
Results: The ductus arteriosus was successfully closed in all eight infants receiving indomethacin, and in seven of eight infants receiving sulindac. No significant differences were found with regards to the ductal size between the two groups at diagnosis or on each of the consecutive days of treatment ( P >0.25). More renal adverse effects were encountered in the indomethacin group. Significant differences in changes from baseline value for urine output, plasma sodium, urea and creatinine concentrations were noted at 24, 48 and 72 h after commencement of treatment between the two groups ( P <0.05). All the parameters returned to normal or pre-treatment levels 48 h after stopping therapy. Unexpectedly, severe gastrointestinal complications were encountered in the sulindac group.
Conclusions: Sulindac is capable of promoting ductal constriction in clinically stable preterm infants without compromising the renal function. The spectrum of gastrointestinal complications observed in sulindac treated infants were similar to those described for indomethacin. The use of sulindac for ductal closure in the preterm infant should remain experimental.  相似文献   
36.
This follow-up study was undertaken in an effort to ascertain the morbidity in the survivors of infants ≤2000 g birthweight cared for in the two Rockhampton intensive care nurseries.

Methodology:


The records of all infants ≤2000 g delivered in or transferred to Rockhampton during the 11 year period 1979 through 1989 inclusive were extracted. Efforts were made to contact and examine all of these children. Those found to be disabled were assessed as being mildly, moderately or severely affected.

Results:


Of the 482 infants of birthweight ≤2000 g treated in the period under review, 393 survived to be discharged from hospital. Eight were known to have died subsequently. Of the remaining 385 children, 288 (74.8%) were able to be contacted and their health status determined. A total of 36 infants were found to have significant disabilities. Twenty-four were mildly affected, five moderately and seven severely affected. Severe disability in infants of ≤1000 g was 16% (3/19).

Conclusions:


The incidence of disability was established in 74.8% of the surviving population, It was not dissimilar to the incidence of disability in similar birthweight groups in some Australian tertiary centres for the years under study. It is emphasized that the follow-up was incomplete and recognized that the survival rates and incidence of disability in survivors has improved in tertiary centres since the time frame of this study.  相似文献   
37.
38.
Introduction: In the growing field of medical education research, participant recruitment can be challenging. Incentives, either tangible or intangible, may be offered to encourage participation. This study aimed to understand these incentives and explore the relationship between study quality and incentives in medical education research.

Methods: We reviewed research studies examining medical trainees published in five major journals in 2008. Tangible and intangible incentives used in recruitment were extracted by two researchers. For each quantitative article, medical education research quality instrument (MERSQI) score was calculated and citation counts for all articles were compiled.

Results: Of 215 included articles, 8% explicitly reported incentives. Tangible incentives (value range $15–$60 USD) were offered in 7.9% of studies. Intangible incentives were identified in 30% of studies but only one specifically discussed their use. Tangible incentives correlated with a higher MERSQI score (p?p?Conclusion: Most studies in medical education did not describe incentives for participation. Information regarding incentives should be reported in all studies to help inform future recruitment efforts and also to understand the study context including factors that may influence participants motivation.  相似文献   
39.
The present report describes a case of severe airway obstruction caused by endobronchial tuberculosis in an 11-year-old girl who was successfully treated by bronchoscopic balloon dilation. This case illustrates the insidious presentation and the increasingly important role of bronchoscopic intervention in the management of endobronchial tuberculosis. In addition, a brief literature review of the condition in the pediatric age group is included.  相似文献   
40.
Endogenous protein phosphorylation by resting and activated human neutrophils   总被引:10,自引:0,他引:10  
Andrews  PC; Babior  BM 《Blood》1983,61(2):333-340
NADPH oxidase is an enzyme in the plasma membrane of the neutrophil that catalyzes the production of O2-, a species central to the oxygen- dependent killing mechanisms of this cell. The oxidase is dormant in resting cells and is activated upon the addition of a stimulus. Neutrophils of patients with chronic granulomatous disease (CGD) manifest no oxidase activity when stimulated. The possible role of protein phosphorylation in the activation of NADPH oxidase was examined in normal and CGD neutrophils by measuring the incorporation of 32Pi into proteins as determined by gel electrophoresis followed by autoradiography. Resting neutrophils from normal subjects exhibit at least 40 distinct phosphoprotein bands. The level of phosphorylation of these bands was examined after the addition of phorbol myristate acetate (PMA), opsonized zymosan, digitonin, N-formyl-methionyl- phenylalanine (FMLP), or NaF. PMA and opsonized zymosan increased the phosphorylation of a set of 6 protein bands. Digitonin and FMLP consistently caused the phosphorylation of 4 of these protein bands, while NaF failed to induce increased phosphorylation of any protein band. All activators tested caused the dephosphorylation of one specific protein band. The time course of phosphorylation (dephosphorylation) was examined using PMA as the activating agent. Increased phosphorylation of one protein band was evident by 12 sec after the addition of PMA. The most slowly phosphorylated protein band did not slow evidence of change until 5 min after the addition of PMA. Three of the phosphoproteins examined were phosphorylated either earlier than or concomitant with the activation of NADPH oxidase. CGD neutrophils were compared with normal cells for their ability to phosphorylate proteins in response to PMA. The phosphoprotein banding patterns of CGD neutrophils were identical with those of normal neutrophils in both the resting and activated states. The evidence presented shows that the phosphorylation of proteins is a prominent feature of neutrophil metabolism. The striking similarity of phosphorylation changes induced by the various activators tested suggests that protein phosphorylation may play a role in some aspects of neutrophil activation. Evidence was not obtained, however, regarding a link between protein phosphorylation and activation of NADPH oxidase.  相似文献   
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