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101.
目的:对中国少年智力量表(CISJ)进行信度分析。方法:采用分半相关、Alpha系数和复测相关等方法对CISJ常模样本资料作统计分析。结果:①分半信度:各分测验及言语、操作和总量表的分半相关系数在0.39-0.92之间,其中各常模年龄组样本,城镇为0.39~0.91、农村为0.42~0.92,而城镇总样本、农村总样本和全体样本则分别为0.57-0.88、0.63~0.90和0.61-0.89。②Alpha系数分析:除4个系数偏低(0.29~0.39)外,其余都比较高,在0.41-0.84之间,0.50以上的达到95%。③复测信度:各分测验及言语、操作、智力因素量表分数和智商的相关系数在0.47-0.85之间;除数字背诵分测验为0.47外,其余均在0.69以上。结论:CISJ具有较高的内部稳定性和复测一致性,是信度比较理想的智力量表。  相似文献   
102.
Human (T,G)-AL specific T cell helper factors secreted by in vitro activated peripheral blood lymphocytes of normal donors were characterized. Factors were passed through columns of Sepharose coupled either to antibodies against human immunoglobulin or antibodies against the variable region of the heavy (Vh) and light (Vl) chains of human immunoglobulin. In addition, the same factors were applied to columns of Sepharose coupled to anti-HLA-DR antibodies or to monoclonal antibodies against human Ia or β2-microglobulin. The activity of the antigen specific factors was removed by the anti-Vh antibodies and not by anti-Vl or anti-human immunoglobulin antibodies. The factors passed through Sepharose coupled to anti-DR antibodies could be removed and eluted from columns of anti-DR antibodies relevant to the donors' DR antigens. The same factors were also removed by a monoclonal antibody (anti-Ia) which recognizes a monomorphic determinant on HLA-DR, but not by monoclonal anti-β2-microglobulin. The results suggest that the genetically regulated (T,G)-AL specific helper factors possess HLA-DR as well as Vh determinants in their active moiety.  相似文献   
103.
Anterior pituitary cells of the GH line, which secrete prolactin spontaneously, showed spontaneous action potential activity. Thyrotrophin releasing factor, which increases secretion in these cells, caused a prompt increase of action potential frequency. Potassium, another secretagogue, depolarized the cells and sometimes initiated a burst of action potentials at the onset of this effect. The action potentials persisted in tetrodotoxin-containing and Na-free media, but were suppressed by the Ca-channel blocker, methoxyverapamil. Moreover, elevating the extracellular Ca2+ concentration increased the amplitude of the action potentials. These action potentials therefore have a prominent Ca component. This endows them with a particular interest since secretory activity of these cells is known to be dependent on extracellular Ca2+. Ba2+, which can substitute for Ca2+ in maintaining secretion, also substituted for Ca2+ in the maintenance of the action potentials. In addition, Ba2+ prolonged action potentials remarkably: tetraethylammonium was less effective in this regard.The several parallels between known secretory behaviour and electrical phenomena encourage the view that analysis of electrical activity in anterior pituitary cells may provide useful clues to events involved in stimulus-secretion coupling and in the secretory control exerted by the brain.  相似文献   
104.
Replicating Ad5 DNA was isolated from nuclei of infected KB cells and studied by electron microscopy. Branched as well as unbranched linear intermediates were observed containing extended regions of single-stranded DNA. The relationship between the branched and unbranched structures was studied during synchronized synthesis in the first round of replication after release of hydroxyurea inhibition. The branched intermediates represented early and the unbranched intermediates late stages in the replication cycle. Digestion of the branched intermediates with Eco RI endonuclease revealed that replication had started at the molecular right end (the A-T-rich end). This was confirmed by partial denaturation mapping of branched intermediates.These results confirm and extend a tentative model on the mechanism of Ad5 DNA replication.  相似文献   
105.
Growth of diploid cells from breast cancers   总被引:1,自引:0,他引:1  
Cell cultures were derived from normal and cancerous breast tissues and from metastases by methods that selected for relatively adherent epithelial aggregates. Karyotypic analyses of first or second passage cultures yielded predominantly normal diploid cells. Nonclonal aberrations were more common in tumor-derived than in normal cultures. Three of the cultures that originated from metastases were characterized by abnormal clones. These results support observations based on DNA content, which indicate that a considerable fraction of breast cancers are composed predominantly of diploid cells. They differ greatly from chromosomal findings in long-term cultures of tumor effusions and thus emphasize the karyotypic diversity that can be found in tumors from a single tissue of origin--the breast.  相似文献   
106.
Two patients with chronic myelogenous leukemia and new variant Philadelphia chromosome translocations are reported. In one case, a 41-year-old male, a 10;22 translocation was found in all bone marrow cells examined. Furthermore, the Y chromosome was missing in 90% of the analyzed metaphase cells. In the second patient, a 22-year-old male, all the marrow cells contained a complex rearrangement involving chromosomes No. 2, 9, and 22.  相似文献   
107.
The role of del (11)(p13) as a cause of aniridia, with and without Wilms tumor, is strengthened by demonstration of this chromosome aberration in 3 patients: monozygous twin girls, both of whom have aniridia and mental retardation and one of whom has a Wilms tumor; and an unrelated boy with aniridia and ambiguous genitalia. The break points defining the interstitial deletion for the twins are 11p13 and 11p15.1, while for the boy they are 11p1302 and 11p14.1. These patients and their karyotypes substantiate the critical importance of chromosome band 11p13 (or its hemizygous representation) in the development of aniridia and an associated Wilms tumor diathesis, as had been suggested previously (Riccardi VM, Sujansky E, Smith AC, Francke U, (1978): Pediatrics 61, 604-610).  相似文献   
108.
To assess the frequency of chromosomal aberrations in French candidates for intracytoplasmic sperm injection (ICSI), and to explore the existence of a female chromosomal factor in some cases of couple infertility, a collaborative retrospective clinical and cytogenetic study was performed, launched by the Association des Cytogénéticiens de Langue Franciaise (ACLF). The karyotypes of 3208 patients [2196 men (68.4%), 1012 (31.6%) women] included in ICSI programmes over a 3-year period in France were collected. A total of 183 aberrant karyotypes was diagnosed, corresponding to an abnormality frequency of 6.1% (134/2196) for men and 4.84% (49/1012) for women. The following frequencies of abnormalities were observed respectively for men and women: 1.23% (n = 27) and 0.69% (n = 7) for reciprocal translocations, 0.82% (n = 18) and 0.69% (n = 7) for Robertsonian translocations, 0.13% (n = 3) and 0.69% (n = 7) for inversions, 3.32% (n = 73) and 2.77% (n = 28) for numerical sex chromosome aberrations, and 0.59% (n = 13) and 0% for other structural aberrations. Among the male patients of this latter group, 0.40% (n = 9) had a Y chromosome abnormality. Among the male patients with numerical sex chromosome abnormalities, 2.23% (n = 49) were 47,XXY, 0.32% (n = 7) were 47,XYY, and 0.77% (n = 17) had a mosaicism for numerical sex chromosome anomalies. All the female patients with sex chromosome abnormalities (2.77%, n = 28) had mosaicism for numerical sex chromosome anomalies. Even if these cases-the significance of which was sometimes questioned-were disregarded in the analysis, 2.08% (21/1012) of abnormal karyotypes remained in women. An overall increased frequency of chromosomal aberrations was found, and this confirmed that in some cases of poor reproductive outcome there may be a contribution of maternal chromosome aberrations. Indeed, the existence of a chromosome abnormality in the female partner was associated with the group of infertile men in which there was no apparent cause of infertility.  相似文献   
109.
The B/C gene of simian virus 40.   总被引:14,自引:0,他引:14  
C J Lai  D Nathans 《Virology》1976,75(2):335-345
Temperature-sensitive B, C, and BC mutants of Simian virus 40 (SV40) map in the late region of the viral genome inHin fragments K, F, J, and G, a DNA segment of about 1200 nucleotide pairs (Lai, C.-J., and Nathans, D. (1975)Virology 66, 70–81). To define the B/C region further, mutants of SV40 with deletions in this genomic segment were constructed by enzymatic excision of DNA from the viral genome, followed by cloning in the presence of a complementing tsA mutant of SV40. After localization of deleted genome segments by analysis of endo R fragments and electron microscopic heteroduplex mapping, selected deletion mutants were tested for complementation by ts mutants and were screened for their ability to produce new viral proteins in infected cells. Complementation tests indicated that B/C deletion mutations are in a cistron distinct from that of tsA and tsD mutations and that the junction between the B/C and D genes is within Hin-K. Two of the deletion mutants produced new proteins detectable in infected cells. More detailed analysis of one of these proteins (of molecular weight 25,000) indicated that it precipitated with antiserum against dissociated SV40 capsids, and that all but one of its lysine-containing tryptic peptides cochromatographed with SV40 VP1 tryptic peptides. We conclude that the B/C gene, containing approximately 1200 nucleotide pairs, codes for VPl. Since deletion mutants lacking Hin-E do not complement B mutants, we suggest that the Hin-E DNA segment has a signal required for expression of the B/C gene.  相似文献   
110.
In the present study we investigated the relevance of spermimmobilization prior to intracytoplasmic sperm injection (ICSI)in the fertilization process. Using supravital staining of thespermatozoa with eosin and studying sperm decondensation with2 mM dithiothreitol (DTT) in conditions imitating sperm handlingduring ICSI, we demonstrated that immobilization of the spermatozoonby squeezing its tail between the glass pipette and the bottomof the dish damages the sperm plasma membrane. Polyvinylpyrrolidone(PVP), which is usually present in the drop with the spermatozoonto facilitate its handling, was found to impede the access ofboth eosin and DTT to the sperm nucleus. We conclude that (i)sperm immobilization prior to ICSI damages the sperm plasmamembrane, that (ii) this damage is sufficient for thiol-reducingagents to gain access to the sperm nucleus, and finally that(iii) PVP possibly interferes with sperm nucleus decondensation.  相似文献   
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