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921.
Chromosome studies of peripheral blood lymphocytes in 25 subjects who had recovered from benzene hemopathy, in four subjects with bone marrow toxicity from benzene, and in three subjects who had recovered from acute benzene poisoning revealed significantly increased rates of “unstable” and “stable” chromosome aberrations which, In most cases, were still present several years after cessation of exposure to the toxic agent and recovery from the poisoning. The follow-up cytogenetic studies showed a tendency toward a decrease in unstable chromosome changes and, generally, a persistence or an increase in stable changes. Bn some cases there was evidence of abnormal clone formation in peripheral blood lymphocytes. Chromosomes of the G group seemed to be involved in stable changes with a frequency higher than expected.  相似文献   
922.
This paper reports experimentally observed effects of influenza virus infection on pulmonary clearance of chromic oxide dust tagged with chromium 51 (51Cr2O3). The usual course of this viral infection produces a stage of acute pneumonitis at 10 to 14 days after exposure, with subsequent, and often permanent, fibrotic scarring of the lung tissue. When 51Cr2O3 was administered simultaneously with, or at 1, 3, 5, 9, or 56 weeks after, virus inoculation, a marked deficiency in pulmonary clearance of the dust was noted. The distribution of retained chromium in the lungs of infected animals was found to depend on the relation between time of infection and time of 51Cr2O3 administration, a relationship which suggests that individuals with respiratory infections are at increased risk from exposure to toxic and radioactive particles.  相似文献   
923.
924.
This paper presents norms for an Italian translation of the Stanford Hypnotic Susceptibility Scale, Form C (SHSS:C; Weitzenhoffer & Hilgard, 1962). Archival data on hypnosis research subjects recruited over a 10-year period of research on hypnosis were pooled, resulting in an aggregate sample of 356 participants (263 female and 93 male). Score distribution, item difficulty levels, and reliability of the SHSS:C were computed. Of this group, 218 subjects were administered the Harvard Group Scale of Hypnotic Susceptibility approximately 3 weeks prior to administration of the SHSS:C. The remaining 138 subjects received only the SHSS:C. Results suggest that the Italian version of the SHSS:C is a reliable and valid measure.  相似文献   
925.
When regenerative processes cannot keep pace with cell death, functional epithelia are replaced by scar. Scarring is characterized by both excessive accumulation of fibrous matrix and persistent outgrowth of cell types that accumulate transiently during successful wound healing, including myofibroblasts (MFs) and progenitors. This suggests that signaling that normally directs these cells to repair injured epithelia is deregulated. To evaluate this possibility, we examined liver repair during different types of liver injury after Smoothened (SMO), an obligate intermediate in the Hedgehog (Hh) signaling pathway, was conditionally deleted in cells expressing the MF-associated gene, αSMA. Surprisingly, blocking canonical Hh signaling in MFs not only inhibited liver fibrosis but also prevented accumulation of liver progenitors. Hh-sensitive, hepatic stellate cells (HSCs) were identified as the source of both MFs and progenitors by lineage-tracing studies in 3 other strains of mice, coupled with analysis of highly pure HSC preparations using flow cytometry, immunofluorescence confocal microscopy, RT-PCR, and in situ hybridization. The results identify SMO as a master regulator of hepatic epithelial regeneration based on its ability to promote mesenchymal-to-epithelial transitions in a subpopulation of HSC-derived MFs with features of multipotent progenitors.  相似文献   
926.
A DNA fingerprinting method known as ALIS‐FLP (amplified ligation selected fragment‐length polymorphism) has been developed for selective and specific amplification of restriction fragments from TspRI restriction endonuclease digested genomic DNA. The method is similar to AFLP, but differs in that only one specific restriction enzyme (TspRI) is used. The cohesive ends of the DNA fragments are ligated with two types of oligonucleotide. A long oligonucleotide containing the primer site and the specific 9 nt 3 prime end, which is complementary to specific 9 nt, cohesive 3 prime end of the TspRI genomic DNA fragment, and a short, degenerated, oligonucleotide covering the remaining TspRI cohesive ends. Other cohesive ends are covered by a short degenerated oligonucleotide lacking the primer site. The ligation mixture is used as a template for amplification using a single primer corresponding to the 5 prime end of the long, specific oligonucleotide. The selection of TspRI digested genomic DNA fragments for amplification is achieved by sequence selective ligation of the specific long oligonucleotide carrying the primer site to both ends of the specific target fragment. This technique allows for differentiation of the organisms without previous knowledge of their DNA sequence. The usefulness of the method is confirmed by genotyping of 70 previously characterized clinical E. coli isolates. The grouping obtained was identical to the results of REA‐PFGE. Versatility of the method is highlighted, i.e. its combining the advantages of the AFLP technique with a simple, rapid and cheap polymerase chain reaction product detection method.  相似文献   
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929.
This study examined whether anxiety, combined with a focus on appearance, would identify individuals most likely to exhibit eating pathology, conceptualized as safety behaviors/avoidance strategies. In particular, we examined appearance contingent self-worth and appearance conversations with friends as possible moderators of the anxiety-disordered eating relation. Participants were 441 women attending a Southeastern university who completed an online survey. Results indicated that those with the three-way combination of high anxiety, high appearance contingent self-worth, and frequent appearance conversations exhibited the most frequent binge eating. While no significant three-way interactions emerged for broad eating pathology and dietary restraint, in both models it was the anxiety × appearance contingent self-worth interaction that accounted for unique variance in these eating patterns. Results provide researchers and clinicians with a better understanding of who experiences various types of disordered eating in association with anxiety and possible points of intervention.  相似文献   
930.
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