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排序方式: 共有10000条查询结果,搜索用时 437 毫秒
991.
Peter R Loewenson Marjorie Ireland Michael D Resnick 《The Journal of adolescent health》2004,34(3):209-215
PURPOSE: To assess reasons for choosing not to have sexual intercourse among two groups: virgins (primary abstainers) and already sexually experienced youth (secondary abstainers). METHODS: 73,464 Minnesota ninth- and twelfth-grade adolescents completed the 1998 Minnesota Student Survey. Respondents identified reasons for abstinence from a checklist from which they could nominate all relevant items. Reasons for each group were analyzed using Chi-square with a conservative criterion value (p <.001) owing to large sample size. Logistic regression was used to examine the associations of gender, grade, and their interactions, with reasons for abstinence. RESULTS: Sixty-six percent reported never having had intercourse (primary abstainers). Among sexually experienced youth, 7.8% reported choosing not to have intercourse (secondary abstainers). Fear of pregnancy was the reason endorsed most often, more by girls than by boys (OR = 26 for primary abstainers, 6.9 for secondary abstainers). Fear of other adverse consequences, such as sexually transmitted infections, parental disapproval, or fear of getting caught, were generally selected by more girls than boys, and by more primary than secondary abstainers. Similarly, more girls and primary abstainers than boys or secondary abstainers generally selected statements reflecting normative beliefs on youth or their friends having intercourse. CONCLUSIONS: Fear of adverse consequences and normative beliefs about the appropriateness of having sexual intercourse were most frequently endorsed as important reasons by both groups of abstainers. 相似文献
992.
Jennifer R. Ellsworth Michael J. Lambert Jennifer Johnson 《Clinical psychology & psychotherapy》2006,13(6):380-391
Recent research has found that measuring, monitoring and providing therapists with feedback about their clients' treatment progress improves treatment outcome. This study assessed the level of agreement between two outcome measures used to measure and monitor treatment progress. The Outcome Questionnaire (OQ‐45) was compared with a shorter, derivative measure, the OQ‐30. Each measure has an associated feedback system, which provides therapists with feedback about their clients' treatment progress. The OQ‐45 and the OQ‐30 demonstrated high levels of agreement in measurement of client outcome. The OQ‐45 feedback system emerged as the most accurate and clinically useful method for providing therapists with feedback about their clients' predicted treatment outcomes. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
993.
Comparison of risk stratification with pharmacologic and exercise stress myocardial perfusion imaging: A meta-analysis 总被引:2,自引:0,他引:2
Navare Sachin M. Mather Jeff F. Shaw Leslee J. Fowler Michael S. Heller Gary V. 《Journal of nuclear cardiology》2004,11(5):551-561
BACKGROUND: Although pharmacologic stress myocardial perfusion imaging (MPI) and exercise stress MPI have comparable diagnostic accuracy, their comparative value for risk stratification of patients with known or suspected coronary disease is not known. METHODS AND RESULTS: The data of 14,918 patients were combined from 24 studies evaluating prognosis in patients undergoing either pharmacologic stress or exercise stress MPI. Studies were included if a 2 x 2 table for hard cardiac events (cardiac death and myocardial infarction [MI]) could be constructed from the data available. Excluded were studies performed for post-MI, post-revascularization, or preoperative risk stratification. A weighted t test was used to compare the cardiac events, and a random effects model was used to calculate summary odds ratios. Summary odds ratios for hard cardiac events were similar for pharmacologic stress and exercise stress MPI. Summary receiver operating characteristic curves also showed no difference in discriminatory power between the stressors. The cardiac event rates were significantly higher with normal and abnormal test results with pharmacologic stress MPI than with exercise stress MPI (1.78% vs 0.65% [P < .001] for normal results and 9.98% vs 4.3% [P < .001] for abnormal results). Subgroup analysis revealed that both cardiac death and nonfatal MI were significantly higher with pharmacologic stress MPI. Patients undergoing pharmacologic stress MPI had a significantly higher prevalence of poor prognostic factors, and meta-regression revealed that exercise capacity was the single most important predictor of cardiac events. CONCLUSIONS: This meta-analysis shows that exercise stress MPI and pharmacologic stress MPI are comparable in their ability to risk-stratify patients. However, patients undergoing pharmacologic stress studies are at a higher risk for subsequent cardiac events. This is true even for those with normal perfusion imaging results. 相似文献
994.
Hyong C Lee Wim van Drongelen Arnetta B McGee David M Frim Michael H Kohrman 《Journal of clinical neurophysiology》2007,24(2):137-146
SUMMARY: Robust, automated seizure detection has long been an important goal in epilepsy research because of both the possibilities for portable intervention devices and the potential to provide prompter, more efficient treatment while in clinic. The authors present results on how well four seizure detection algorithms (based on principal eigenvalue [EI], total power, Kolmogorov entropy [KE], and correlation dimension) discriminated between ictal and interictal EEG and electrocorticoencephalography (ECoG) from four patients (aged 13 months to 21 years). Test data consisted of 46 to 78 hours of continuously acquired EEG/ECoG for each patient (245 hours total), and the detectors' accuracy was checked against seizures found by a board-certified neurologist and an experienced registered EEG technician. The results were patient-specific: no algorithm performed well on a 13-month-old patient, and no algorithm consistently performed best on the other three patients. One of the metrics (EI) supported the existence of a postictal period of 5 to 15 minutes in the three oldest patients, but no strong evidence of a preictal anticipation was found. Two metrics (EI and KE) cycled continuously with a period of several hours in a 21-year-old patient, highlighting the importance of continuous analysis to differentiate background cycling from anticipation. 相似文献
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999.
Internalization of sst2, sst3, and sst5 receptors: effects of somatostatin agonists and antagonists. 总被引:4,自引:0,他引:4
Renzo Cescato Stefan Schulz Beatrice Waser Véronique Eltschinger Jean E Rivier Hans-Jürgen Wester Michael Culler Mihaela Ginj Qisheng Liu Agnes Schonbrunn Jean Claude Reubi 《Journal of nuclear medicine》2006,47(3):502-511
The uptake of radiolabeled somatostatin analogs by tumor cells through receptor-mediated internalization is a critical process for the in vivo targeting of tumoral somatostatin receptors. In the present study, the somatostatin receptor internalization induced by a variety of somatostatin analogs was measured with new immunocytochemical methods that allow characterization of trafficking of the somatostatin receptor subtype 2 (sst2), somatostatin receptor subtype 3 (sst3), and somatostatin receptor subtype 5 (sst5) in vitro at the protein level. METHODS: Human embryonic kidney 293 (HEK293) cells expressing the sst2, sst3, or the sst5 were used in a morphologic immunocytochemical internalization assay using specific sst2, sst3 and sst5 antibodies to qualitatively and quantitatively determine the capability of somatostatin agonists or antagonists to induce somatostatin receptor internalization. In addition, the internalization properties of a selection of these agonists have been compared and quantified in sst2-expressing CHO-K1 cells using an ELISA. RESULTS: Agonists with a high sst2-binding affinity were able to induce sst2 internalization in the HEK293 and CHO-K1 cell lines. New sst2 agonists, such as Y-DOTA-TATE, Y-DOTA-NOC, Lu-DOTA-BOC-ATE (where DOTA is 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid; TATE is [Tyr3, Thr8]-octreotide; NOC is [1-NaI3]-octreotide; and BOC-ATE is [BzThi3, Thr8]-octreotide), iodinated sugar-containing octreotide analogs, or BIM-23244 were considerably more potent in internalizing sst2 than was DTPA-octreotide (where DTPA is diethylenetriaminepentaacetic acid). Similarly, compounds with high sst3 affinity such as KE108 were able to induce sst3 internalization. In sst2- or sst3-expressing cell lines, agonist-induced receptor internalization was efficiently abolished by sst2- or sst3-selective antagonists, respectively. Antagonists alone had no effect on sst2 or sst3 internalization. We also showed that somatostatin-28 and somatostatin-14 can induce sst5 internalization. Unexpectedly, however, potent sst5 agonists such as KE108, BIM-23244, and L-817,818 were not able to induce sst5 internalization under the same conditions. CONCLUSION: Using sensitive and reproducible immunocytochemical methods, the ability of various somatostatin analogs to induce sst2, sst3, and sst5 internalization has been qualitatively and quantitatively determined. Whereas all agonists triggered sst2 and sst3 internalization, sst5 internalization was induced by natural somatostatin peptides but not by synthetic high-affinity sst5 agonists. Such assays will be of considerable help for the future characterization of ligands foreseen for nuclear medicine applications. 相似文献
1000.
Hagit Cohen Joseph Zohar Michael A Matar Zeev Kaplan Amir B Geva 《Neuropsychopharmacology》2005,58(8):640-650
BACKGROUND: Unsupervised fuzzy clustering (UFC) analysis is a mathematical technique that groups together objects in the multidimensional feature space according to a specified similarity measurement, thereby yielding clusters of similar data points that can be represented by a set of prototypes or centroids. METHODS: Since clinical studies of mental disorders distinguish between affected and unaffected individuals, we designed an inclusion/exclusion criteria (cutoff behavioral criteria [CBC]) approach for animal behavioral studies. The effect of classifying the study population into clearly affected versus clearly unaffected individuals according to behaviors on two behavioral paradigms was statistically significant. RESULTS: Here the raw data from previous studies were subjected to UFC algorithms as a means of objectively testing the validity of the concept of the CBC for our experimental model. The first UFC algorithm yielded two clearly discrete clusters, found to consist almost exclusively of the exposed animals in the one and unexposed animals in the other. The second algorithm yielded three clusters corresponding to animals designated as clearly affected, partially affected, and clearly unaffected. The algorithm for physiological data in addition to behavioral data failed to elicit discrete clusters. CONCLUSIONS: The UFC analysis yielded data that support the conceptual contention of the CBC and lends additional validity to our previous behavioral studies. 相似文献