红细胞分化调节因子对体外培养的L929和KB细胞的生长抑制作用

从兔网织红细胞提纯的红细胞分化调节因子(erythroid differentiation factor,EDF),能对体外培养的自发转化成纤维细胞系L929及人鼻咽癌细胞系KB产生作用。当EDF剂量为0.10μg/ml时,可引起L929细胞形态发生改变,并有细胞核固缩现象。第2d的细胞生长抑制率为64.86％,软琼脂集落形成率为0;第5d时细胞增殖为负值。~3H-TdR掺入率明显降低。EDF剂量为0.15μg/ml时,对KB细胞生长已有抑制作用。EDF剂量达0.30μg/ml时,生长抑制明显。以上结果证明了EDF对恶性细胞具有增殖抑制作用。这种作用对不同种类细胞敏感性不同,并且与剂量呈正相关。     

表面磁性膜医用316L不锈钢支架的生物相容性

目的 对表面磁性膜血管内支架进行生物相容性研究,为该支架的临床应用提供实验依据.方法 通过溶血实验、动态凝血时间实验、急性全身毒性实验、皮内刺激实验、细胞毒性实验、热源实验、过敏实验、体内植入实验综合评价表面磁性膜血管内支架的生物相容性.结果 表面磁性膜血管内支架无溶血反应及凝血功能的改变,无急性全身毒性反应,无热源反应,支架材料中不存在致敏性物质;支架材料动物体内植入在初期有轻度的炎性反应,12周后炎性反应基本消失,未见炎性细胞浸润积聚现象.结论 表面磁性膜血管内支架具有良好的生物相容性,其应用于临床具有可行性和安全性.     

股骨粗隆间骨折采用改良L形钢板内固定的生物力学原理与临床应用

作者自1994年始采用自行设计L形钢板内固定治疗不稳定股骨粗隆间骨折60例，平均随访25个月，X线片显示骨折愈合时间6～13周，平均8．9周，伤肢功能在3个月内基本恢复正常，无骨折延迟愈合及髋内翻现象。为论证改良L形钢板的优点，本文采用8具新鲜尸股骨沿着它的外侧、内侧骨皮质粘贴6个应变片，观察股骨近端应变和位移分布，以检验改良L形钢板固定粗隆间骨折的效果。在实验前后将股骨粗隆造成二部分或四部分骨折。利用实验结果给制成应变和位移图，并与鹅头打固定组相比较。在载荷加至1800N时比较两种内固定器械的生物力学性能。结果表明，在治疗不稳定粗隆间骨折中，L形钢板比鹅头钉更具有生物力学的优势。     

Biochemical characterization of I-Ak proteins from mutant antigen-presenting B-cell--B-lymphoma hybridomas

Chemically induced mutants of an I-Ak,d expressing antigen-presenting B-cell--B-lymphoma hybridoma have recently been generated by immunoselection in vitro and were found to possess alterations in some of their serologically and functionally defined I-Ak region dependent functions. In order to identify at the structural level the origin of the differences in serological and functional properties of these mutants, I-Ak molecules from several of these mutant hybridomas were compared biochemically to wild-type I-Ak polypeptides by two-dimensional gel electrophoresis and high-pressure liquid chromatographic tryptic peptide analyses. Two-dimensional gel electrophoresis indicated that no major structural alterations, resulting in changes in mol. wt or charge, had occurred in the Ak alpha or Ak beta polypeptides from the mutant cells. Likewise, Ak alpha peptide maps of the mutants were indistinguishable from the normal Ak alpha peptide maps. However, two of the three mutants studied did exhibit one additional peptide in their Ak beta peptide maps. These results suggest that the major deficiencies in T-cell-activating functions of these mutants are a result of a limited alteration in the Ak beta polypeptide primary structure.     

A metacognitive model of social anxiety: Implications for treatment

This article represents an attempt to clarify questions posed by evidence of varying pathways to change in social anxiety. A new perspective is developed which addresses these questions and, importantly, lays the foundation for an innovative treatment approach. Essentially, social anxiety is construed here as the product of a disorganization in which feelings and cognitions (both conscious and preconscious) about the self, about other people, and about the relations between self and others are organized. Specifically, the socially anxious client experiences others autocentrically: that is, in terms of how the other person perceives, evaluates and affects one's own self. The result is a narrowed capacity for experiencing others. The goal of treatment in the new approach advocated here is to allow the individual to understand, appreciate and share the feelings, thoughts and experience of other people. Therapy is directed toward getting clients out of themselves and into other people.     

High-frequency inter-parental recombination between mitochondrial genomes of rice cybrids

Analyzing more than 100 independent rice cybrids, we found evidence for inter-molecular recombination between parental mitochondrial genomes occurring at high frequency soon after protoplast fusion. The structure of the region around the atp6 gene showed extensive polymorphism among Indica (MTC-5A), Japonica (Nipponbare), and wild abortive (IR58024A) mitochondrial genomes. Recombination between the mitochondrial genomes of IR58024A and MTC-5A around the atp6 gene was detected by Southern-blot analysis of cybrid plants. Such recombinant mitochondrial molecules were also cloned from IR58024A/Nipponbare cybrid callus. PCR analysis around the atp6 gene demonstrated that inter-parental recombination occurs in practically all cybrid calli within 2 weeks after protoplast fusion. At this point, parental and recombinant mitochondrial genomes coexisted within the callus. Over the course of further cultivation, however, mitochondrial genome diversity decreased as parental and/or recombinant genomes segregated out.     

The familial prevalence in second-degree relatives of patients with anxiety neurosis (panic disorder)

A family history study of second-degree relatives of 19 patients with anxiety neurosis (panic disorder) and 19 controls showed a morbidity risk of 9.5% among the former compared with 1.4% among the latter. These risks were approximately half those found among first-degree relatives. Female relatives were at higher risk for anxiety neurosis. The risk for other psychiatric illnesses did not differ between the relatives of anxiety neurosis and controls.     

T suppressor lymphocytes reverse ongoing acute allograft rejection

(LEW X BN)F1 cardiac allografts are rejected within 8 days in untreated LEW recipients. At the critical time point of 5 days after transplantation, the obviously rejecting grafts are enlarged and maximally infiltrated by host cells as shown by 111In-labeled lymphocyte tracer studies. However, when such hearts were retransplanted back to naive (LEW X BN)F1 secondary hosts, they survive indefinitely, showing that even late rejection is reversible in the absence of sustained host immunological drive. Attempts were then made to abrogate this advanced immune responsiveness using Cyclosporine (CsA). CsA therapy (15 mg/kg/day for 7 days) starting from day 5 produced indefinite graft survival, similar as if initiated at the time of operation. Addition of exogenous IL-2, which drives the proliferation of Tc, could not reverse this effect. Serial changes in phenotype of lymphocyte subpopulations infiltrating both acutely rejecting and indefinitely functioning cardiac allografts in unmodified and CsA treated hosts, respectively, were then studied. Ratio of Th:Tc/s cells in acutely rejecting grafts was 1.6 by day 3; it inverted abruptly to 0.7 by day 5-6, suggesting predominance of Tc/s during the later stages of allograft rejection. Similarly, treatment with CsA produced a transient depression of Th, with recovery of original Th:Tc/s ratio during the next 2-3 weeks. Adoptive transfer experiments were then performed to investigate the functional significance of these findings.(ABSTRACT TRUNCATED AT 250 WORDS)     

THE EFFECTS OF CHANGES IN AROUSAL LEVEL ON CRITICAL FLICKER FUSION FREQUENCY AND FIGURAL REVERSAL TASKS

The present study was designed to investigate the relationship between intra-and inter-individual differences in arousal level and performance on both critical flicker fusion frequency and figural reversal tasks. Forty male undergraduate Ss were used. Electrical skin conductance was used as the indicant of arousal level. For the intra-individual comparisons white noise was used to increase the Ss’arousal levels. Significant inverted U-shaped relationships were found between both flicker fusion thresholds and rates of figural reversal and skin conductance between individuals. A significant curvilinear relationship was found between rates of figural reversal and level of conductance within individuals. No significant curvilinear relationship was found between flicker fusion thresholds and level of conductance within individuals.     

Genome of the European elk papillomavirus (EEPV)

The genome of the European elk papillomavirus (EEPV) was found to be 8,095 base pairs (bp) long and its genetic organization was similar to that of other papillomaviruses. Ten open reading frames (ORFs), designated E1-E7 and L1-L3, were identified in the genome, all located on one strand. The presence of the L3 ORF is rare among the papillomaviruses and to date has only been identified in the genomes of EEPV, the deer papillomavirus (DPV) and the Cottontail papillomavirus (CRPV). The ORF is well conserved beteeen DPV and EEPV with regard to both length and sequence. Potential promoter regions were identified at the 5-end of the E6 ORF, at the 3-end of the E1 ORF and downstream of the L1 ORF. Furthermore, two potential polyadenylation signals were found, one located in the long control region (LCR), downstream of the L1 ORF, and another preceding the L2 ORF. The EEVP genome is closely related to the genome of the DPV, the most highly conserved regions being ORFs E1 (70%), E5 (69%), and L1 (74%).