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741.
In order to determine the incidence of familial and hereditary ovarian cancer in a referral patient population, we conducted a retrospective study of 44 patients from a consecutive set of 62 patients treated for ovarian carcinoma at the Gynecologic Oncology Clinic at the Richland Memorial Hospital Center for Cancer Treatment and Research between January 1, 1993 and December 31, 1993. In our study of the referred patients, only two (4.55%) reported a history of at least one first-degree relative also being affected with ovarian cancer. However, 13 patients (29.55%) reported a family history consistent with one of the hereditary ovarian cancer syndromes. In addition to having a suggestive family history, these 13 families demonstrated several cardinal features of hereditary cancer syndromes including early onset, bilaterality, multiple primary tumors, and transmission. Race was the only significantly different demographic factor between the hereditary and sporadic ovarian cancer groups. All 13 patients who appeared to have a hereditary form of cancer were Caucasian.  相似文献   
742.
Conventional covariance structure analysis, such as factor analysis, is often applied to data that are obtained in a hierarchical fashion, such as siblings observed within families. A more appropriate specification is demonstrated which explicitly models the within-level and between-level covariance matrices of sibling substance use and intrafamily conflict. Participants were 267 target adolescents (mean age=13.11 years) and 318 siblings (mean age=15.03 years). The level of homogeneity within sibling clusters, and heterogeneity among families, was sufficient to conduct a multilevel covariance structure analysis (MCA). Parental and family-level variables consisting of marital status, socioeconomic status, marital discord, parent use, and modeling of substances were used to explain heterogeneity among families. Marital discord predicted intrafamily conflict, and parent marital status and modeling of substances predicted sibling substance use. Advantages and uses of hierarchical designs and conventional covariance structure software for multilevel data are discussed.  相似文献   
743.
Discovering that participants who received therapy in a research project and were being debriefed in a therapy outcome study considered those assessment sessions therapeutic, the authors conclude that participants: (a) are aware of the research context, (b) have some idea about how it affected the treatment they got, and (c) see positive outcomes for taking part in the study. Assessment and treatment were not separated in the minds of some participants, as they had been in the mind of the researchers.This study was supported in part by National Institute on Drug Abuse grant #1R 18DA 1069232001.  相似文献   
744.
To this stage a large amount of information has accumulated on one-dimensional broadband frequency channel characteristics of the visual system. Only recently have attempts been made to define additional two-dimensional narrow-band response profiles-particularly in central vision. In this paper questions concerning the number, tuning widths and phase sensitivity of such two-dimensional narrow-band coding units are reviewed. Results with grating and two-dimensional images are discussed, particularly within the context of energy processing and information reduction strategies which reflect human performance. Finally, a consequent principle of univariance is defined and shown to hold with such filter units.  相似文献   
745.
Patterns of visual selection were recorded as Ss viewed pairs of stimulus drawings in which the two members were either both incongruous or both banal. Prior to presenting the paired stimuli, S was preexposed to either one member of the stimulus pair or to the incongruous or banal counterpart of one member of the stimulus pair. The results indicate that: (1) preexposure to a stimulus reduced its potential to elicit looking responses, and the magnitude of that reduction was greater for incongruous stimuli than for banal stimuli; (2) preexposure to an incongruous stimulus affected the potential of its banal counterpart to elicit looking responses, but preexposure to a banal stimulus did not affect the potential of its incongruous counterpart to elicit similar responses; and (3) the reduced potential of the preexposed member of a stimulus pair to elicit looking responses waned after 10 sec. These results were discussed in light of an “information-conflict resolution” model of visual selection.  相似文献   
746.
Recent research on nicotine self-administration has highlighted the need to accurately assess within-cigarette topography in order to estimate changes in puff profiles that occur in response to varying nicotine content. This paper describes equipment and techniques that may be used to record puff volume in the laboratory and discusses methods used by other researchers to study puff volume with an emphasis on methodological advantages of the present technique.  相似文献   
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749.
Role relations in the public school are viewed within the perspective of organization theory; the public school is like the prison and the public mental hospital in that neither client nor organization exercises choice concerning client participation in the organization. Based on previous studies of prisons and mental hospitals and on clues provided in a case study of a junior high school, it was predicted that counselors and principals would be less “custodial” in pupil control ideology than teachers. An instrument that measured pupil control ideology along a custodial-humanistic continuum was administered to 945 teachers, 181 principals, and 180 counselors. Results confirmed the predictions. Counselor adaptations to ideological conflict concerning pupil control in both the secondary and the elementary school are discussed. It was speculated that adaptations would function to reduce overt conflict and contribute to organizational equilibrium.  相似文献   
750.
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