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61.
The use of purified specific antibodies against HMG1 and HMG17 (high mobility group nonhistone chromosomal proteins), together with a very sensitive solid phase enzyme immunoassay, allows the detection of nanograms of these proteins free in solution or in chromatin native structure, and the measurement of their accessibility. The sensitivity of the assay is comparable to that of the radioimmunoassay, with the advantage of avoiding the handling of radioactive materials.  相似文献   
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Serial cytogenetic studies have been performed in four patients with myelodysplastic syndromes. In all four a 5q- alteration was present, but with a different pattern of presentation. One patient presented 5q- as the only alteration since diagnosis; two patients acquired this alteration during the course of the disease; and the fourth showed a 5q- plus other alterations since the first cytogenetic study. Likewise, three of the four patients showed a clone with trisomy 8 and without 5q-. According to these observations and others from the literature with similar cytogenetic behavior, we have analyzed the following points: 5q- as a primary event and as the only alteration, 5q- as a secondary event, 5q- plus other alterations, and presence of cytogenetically different clones. Analysis of these points suggests that the 5q- alteration can represent an early mutation conferring a slow capacity of expansion to the affected clones, with the possibility of cytogenetic evolution during the progression of the disease (about 30% of the patients). Likewise, the association of trisomy 8 clones with 5q- clones can be a nonrandom event.  相似文献   
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The products resulting from the reaction of PVC with sodium benzenethiolate were degraded to 0,3% at 180°C in the solid state and at 160°C in solution in trichlorobenzene. The polyene distribution of the polymers after degradation was studied by both UV-visible and resonance Raman spectroscopies, as a function of the degree of substitution. The results show that there are two types of behaviour: that of the PVC sample prior to the substitution reaction together with the samples modified up to a definite degree of substitution which depends on the starting isotactic content, and that of samples with higher degrees of substitution. The former group exhibits not only a steady improvement in thermal stability but also a preferential formation of polyenes of 7 – 9 double bonds whose concentration decreases with increasing degree of substitution. Conversely, for the second group of samples the thermal stability decreases with the degree of substitution and no specific absorption bands are observed. On the basis of earlier work on the selective substitution of the isotactic GTTG and heterotactic TTTG triads during the first stage of the reaction, the present results show that the bands at 393, 416, and 437 nm are related to specific polyenes which result from initiation by the above quoted conformations in PVC, a conclusion for which confirmatory evidence was obtained by resonance Raman spectroscopic examination of the samples. There is, therefore, clear evidence for the occurrence of two distinct degradation mechanisms, one involving initiation by the unstable triad conformations and the other via random initiation at stable and normal structures. To this may be added the initiation by defect structures, which have been extensively documented in the literature.  相似文献   
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Health agencies call for the immediate mobilization of existing interventions in response to numerous child and family mental health concerns that have arisen as result of the COVID-19 pandemic. Answering this call, this pilot study describes the rapid, full-scale change from a primarily clinic-based Parent–Child Interaction Therapy (PCIT) model to a virtual service model (i.e., I-PCIT) in an academic and community-based program in Miami, Florida. First, we describe the virtual service training model our program developed and its implementation with 17 therapists (MAge?=?32.35, 88.2% female, 47.1% Hispanic) to enable our clinic to shift from providing virtual services to a small portion of the families served (29.1%) to all of the families served. Second, we examine the effect of I-PCIT on child and caregiver outcomes during the 2-month stay-at-home period between March 16, 2020, and May 16, 2020, in 86 families (MChildAge?=?4.75, 71% Hispanic). Due to the rapid nature of the current study, all active participants were transferred to virtual services, and therefore there was no comparison or control group, and outcomes represent the most recently available scores and not treatment completion. Results reveal that I-PCIT reduced child externalizing and internalizing problems and caregiver stress, and increased parenting skills and child compliance with medium to large effects even in the midst of the COVID-19 pandemic. Finally, the study examined components of our virtual service training model associated with the greatest improvements in child and caregiver outcomes. Preliminary findings revealed that locally and collaboratively developed strategies (e.g., online communities of practice, training videos and guides) had the strongest association with child and caregiver outcomes. Implications for virtual service delivery, implementation, and practice in the midst of the COVID-19 pandemic are discussed.

  相似文献   
67.
ObjectiveBuilding on the original taxonomy of hospital‐based health systems from 20 years ago, we develop a new taxonomy to inform emerging public policy and practice developments.Data SourcesThe 2016 American Hospital Association''s (AHA) Annual Survey; the 2016 IQVIA Healthcare Organizations and Systems (HCOS) database; and the 2017‐2018 National Survey of Healthcare Organizations and Systems (NSHOS).Study DesignCluster analysis of the 2016 AHA Annual Survey data to derive measures of differentiation, centralization, and integration to create categories or types of hospital‐based health systems.Data CollectionPrincipal components factor analysis with varimax rotation generating the factors used in the cluster algorithms.Principal FindingsAmong the four cluster types, 54% (N = 202) of systems are decentralized (−0.35) and relatively less differentiated (−0.37); 23% of systems (N = 85) are highly differentiated (1.28) but relatively decentralized (−0.29); 15% (N = 57) are highly centralized (2.04) and highly differentiated (0.65); and approximately 9 percent (N = 33) are least differentiated (−1.35) and most decentralized (−0.64). Despite differences in calculation, the Highly Centralized, Highly Differentiated System Cluster and the Undifferentiated, Decentralized System Cluster were similar to those identified 20 years ago. The other two system clusters contained similarities as well as differences from those 20 years ago. Overall, 82 percent of the systems remain relatively decentralized suggesting they operate largely as holding companies allowing autonomy to individual hospitals operating within the system.ConclusionsThe new taxonomy of hospital‐based health systems bears similarities as well as differences from 20 years ago. Important applications of the taxonomy for addressing current challenges facing the healthcare system, such as the transition to value‐based payment models, continued consolidation, and the growing importance of the social determinants of health, are highlighted.  相似文献   
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We studied 22 gynecological tumors for mutations in exons 5 through 8 of the p53 gene by means of SSCP analysis, using a simplified, nonradioactive technique developed at our laboratory. In order to test the procedure, we carried it out in parallel with the usual radioactive one. Two coincident mutations (in exons 5 and 8) were found by means of both methods. However, an additional one in exon 6 was found by means of our nonradioactive technique. This simplified method for SSCP-analysis of the p53 gene in human tumors is faster, easier and cheaper to perform than the conventional radioactive method, and yields equivalent results. It could be thus an excellent candidate for routine use in the clinical setting.  相似文献   
70.
Iron deficiency is the most frequent form of nutritional anemia, and infants represent one of the major risk groups. The present study was meant to evaluate the iron content of infant diets cooked in iron utensils and in aluminum utensils prepared by volunteer mothers at home. The iron content was analyzed by atomic absorption spectrophotometry. The increase of iron in diets cooked in iron utensils was 12 to 44 times greater than in diets cooked in aluminum utensils. The pH and moisture of the diets cooked in the two types of utensils did not differ in a statistically significant manner. On the basis of these results, it was estimated that the increase in daily iron supply obtained by cooking the diet in iron utensils would be sufficient to satisfy the iron requirements of infants.  相似文献   
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