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Psychotherapists' reactions to patients with borderline personality disorder were assessed by semantic differential ratings in an analogue study. Vignettes presented one of two patients who enacted the Rewarding and Withdrawing object relations units in two separate therapy sessions. In response to the Rewarding object relations unit therapists evaluated themselves more positively and perceived themselves as more active and more potent than in response to the Withdrawing object relations unit (p less than .01). They also evaluated the patients more positively and perceived them as less active (p less than .01). These patterns were modified by some order effects and some differences in response to the two vignettes, which represented a lower and higher functioning borderline patient.  相似文献   
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Immunosuppression evoked by delta 9-tetrahydrocannabinol (delta 9-THC) has been a consistent finding in rats but the development of tolerance to this phenomenon has not been explored. Therefore, Fischer rats of both sexes were orally given delta 9-THC at 6 or 12 mg/kg or sesame oil as vehicle control for 5-26 days before and after I.P. antigenic stimulation with sheep red blood cells (SRBC). delta 9-THC doses were relevant to those of man and produced mild CNS-inhibition followed by CNS-stimulation, tolerance developing to both behavioral phases. The primary immune response was evaluated by determining splenic antibody-forming cells (AFC), hemagglutinin (HT) and/or hemolysin (HS) titers. Simultaneous administration of delta 9-THC and SE induced dose-related splenic atrophy and reduced AFC proliferation as well as HT and HS responses. These changes were not elicited by sesame oil. Tolerance did not develop to immunosuppression during 26 days of cannabinoid treatment. delta 9-THC given 3 days post SRBC inoculation induced immunosuppression at 12 but not 6 mg/kg. Immunosuppression was directly related to delta 9-THC rather than to non-specific debilitating factors since body weights are stable. The inductive phase of the primary immune response was most sensitive to impairment although the reproductive phase was also affected at the high dose level.  相似文献   
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PurposeTo evaluate whole-lesion 3D-histogram apparent diffusion coefficient (ADC) metrics for assessment of pancreatic malignancy.MethodsForty-two pancreatic malignancies (36 pancreatic adenocarcinoma [PDAC], 6 pancreatic neuroendocrine [PanNET]) underwent abdominal magnetic resonance imaging (MRI) with diffusion-weighted imaging before endoscopic ultrasound biopsy or surgical resection. Two radiologists independently placed 3D volumes of interest to derive whole-lesion histogram ADC metrics. Mann-Whitney tests and receiver operating characteristic analyses were used to assess metrics’ diagnostic performance for lesion histology, T-stage, N-stage, and grade.ResultsWhole-lesion ADC histogram metrics lower in PDACs than PanNETs for both readers (P ≤ .026) were mean ADC (area under the curve [AUC] = 0.787-0.792), mean of the bottom 10th percentile (mean0-10) (AUC = 0.787-0.880), mean of the 10th-25th percentile (mean10-25) (AUC = 0.884-0.917) and mean of the 25th-50th percentile (mean25-50) (AUC = 0.829-0.829). For mean10-25 (metric with highest AUC for identifying PDAC), for reader 1 a threshold > 0.94 × 10?3 mm2/s achieved sensitivity 94% and specificity 83%, and for reader 2 a threshold > 0.82 achieved sensitivity 97% and specificity 67%. Metrics lower in nodal status ≥ N1 than N0 for both readers (P ≤ .043) were mean0-10 (AUC = 0.789-0.822) and mean10-25 (AUC = 0.800-0.822). For mean10-25 (metric with highest AUC for identifying N0), for reader 1 a threshold <1.17 achieved sensitivity 87% and specificity 67%, and for reader 2 a threshold <1.04 achieved sensitivity 87% and specificity 83%. No metric was associated with T-stage (P > .195) or grade (P > .215).ConclusionVolumetric ADC histogram metrics may serve as non-invasive biomarkers of pancreatic malignancy. Mean10-25 outperformed standard mean for lesion histology and nodal status, supporting the role of histogram analysis.  相似文献   
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Rationale and ObjectivesTo assess gender balance amongst invited speakers at 2 national radiology conferences over the past decade.Materials and MethodsThe 2009, 2014, and 2019 Association of University Radiologists (AUR) and American Roentgen Ray Society (ARRS) conference programs were evaluated for the number and gender of invited speakers, as well as various presentation characteristics. Gender balance was stratified across conferences and years.ResultsThe final analysis included 1657 invited speakers and 45, 602 minutes of presentation. AUR showed a nonsignificant increase in the percent of presentations by women from 42.2% to 46.5% and in the percent of distinct female presenters from 41.6% to 46.0%. For ARRS, percentage of female presenters varied minimally from 36.1% to 38.2%. In AUR 2009, female presenters spoke on average 5.7min less than men (P= 0.042) and 6.5% of women gave lectures over 30 minutes vs 22.2% of men (P = 0.032). Subsequent AUR and ARRS conferences did not demonstrate presentation length disparities. For AUR, no keynote female speaker was identified. For ARRS, there was no significant difference in percentage of keynote speakers based on gender (P ≥0.516). A disproportionately high percentage of presentations before 8am (44.4%-66.7%) were by women.ConclusionFemale representation was greater than among the overall radiology workforce, highlighting a role of national societies in promoting female radiologists. Nonetheless, such representation is confounded by disproportionate underrepresentation in visibility of invited talks. While improvement in some presentation measures were observed, continued efforts are warranted to promote equal opportunities for female radiologists at national conferences.  相似文献   
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PurposeTo explore the current state of teleradiology practice, defined as the interpretation of imaging examinations at a different facility from where the examination was performed.MethodsA national survey addressing radiologists’ habits, attitudes, and perceptions regarding teleradiology was distributed by e-mail to a random sample of ACR members in early 2019.ResultsAmong 731 of 936 respondents who indicated a non-teleradiologist primary work setting, 85.6% reported performing teleradiology within the past 10 years and 25.4% reported that teleradiology represents a majority of their annual imaging volumes; 84.4% performed teleradiology for internal examinations and 45.7% for external examinations; 46.2% performed teleradiology for rural areas and 37.2% for critical access hospitals; 91.3% performed teleradiology during weekday normal business hours and 44.5% to 79.6% over evening, overnight, and weekend hours. In all, 76.9% to 86.2% perceived value from teleradiology for geographic, after-hours, and multispecialty coverage, as well as reduced interpretation turnaround times. The most common challenges for teleradiology were electronic health record access (62.8%), quality assurance (53.8%), and technologist proximity (48.4%). The strategy most commonly considered useful for improving teleradiology was technical interpretation standards (33.3%). Radiologists in smaller practices were less likely to perform teleradiology or performed teleradiology for lower fractions of work, were less likely to experience coverage advantages of teleradiology, and reported larger implementation challenges, particularly relating to electronic health records and prior examination access.ConclusionDespite historic concerns, teleradiology is widespread throughout modern radiology practice, helping practices achieve geographic, after-hours, and multispecialty coverage; reducing turnaround times; and expanding underserved access. Nonetheless, quality assurance of offsite examinations remains necessary. IT integration solutions could help smaller practices achieve teleradiology’s benefits.  相似文献   
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