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81.
Survival, mutagenesis, and host cell reactivation in a Chinese hamster ovary cell ERCC1 knock-out mutant 总被引:2,自引:0,他引:2
Rolig Rhonda L.; Layher Susan K.; Santi Barbara; Adair Gerald M.; Gu Feng; Rainbow Andrew J.; Nairn Rodney S. 《Mutagenesis》1997,12(4):277-283
Positive selection-negative selection gene targeting was usedto disrupt the nucleotide excision repair gene ERCC1 in a Chinesehamster ovary cell line, CHO-K1. Southern and Northern analysisshowed that a cell clone isolated by this targeting approach,CHO-7-27, had an ERCC1 gene structure consistent with targeteddisruption of ERCC1 exon V, and did not express ERCC1 mRNA.CHO-7-27 was further characterized with respect to UV and mitomycinC sensitivities, and was shown to exhibit severe mutagen sensitivityphenotypes consistent with those of other CHO cell ERCC1 mutants.Mutation frequency experiments showed that CHO-7-27 was UV-hypermutableat the hypoxanthine-guanine phosphoribosyltransferase locus.Experiments assessing host cell reactivation of viral DNA synthesisfor UV-irradiated adenovirus showed that CHO7-27 exhibited aseverely deficient HCR phenotype similar to that of UV20 cells.Our results demonstrate that CHOK1 cells are hemizygous forthe ERCC1 gene, and show that the comparatively mild mutagensensitivities and lack of severely deficient HCR phenotypesof conventionally derived CHO-K1 ERCC1 mutants, in contrastto the severe phenotypes of CHO-AA8-derived mutants, are notdue to any intrinsic genetic differences between CHO-K1 andCHO-AA8 parental cell lines.
4To whom correspondence should be addressed 相似文献
82.
Megakaryocytic Progenitors Can Be Generated Ex Vivo and Safely Administered to Autologous Peripheral Blood Progenitor Cell Transplant Recipients 总被引:9,自引:1,他引:8
83.
Sheri Thompson-Henry M.A. C.C.C.-S.L.P. Barbara Braddock M.H.S. C.C.C.-S.L.P. 《Dysphagia》1995,10(3):172-174
The modified Evan's blue dye procedure (MEBD) is a method of performing tracheal suctioning of the patient through the tracheostomy tube after administration of color-contrasted food and liquid. The MEBD is done when radiographic or fiberoptic procedures are not available or practical. In 5 tracheostomized patients, the MEBD does not detect aspiration. 相似文献
84.
Dr. Barbara McGee Hughes Pharm.D. Dr. Ralph E. Small Pharm.D. Dr. Douglas Brink Pharm.D. Dr. Norma D. McKenzie M.D. 《Pharmacotherapy》1997,17(1):113-120
Study Objective . To evaluate the effects of flurbiprofen therapy on the pharmacokinetics of lithium. Design . Placebo-controlled, single-blind, crossover study. Setting . University-affiliated hospital. Patients . Eleven healthy women with bipolar disorder. Interventions . The subjects received therapeutic doses of lithium administered as an immediate-release capsule every 12 hours. In addition, they received one placebo tablet every 12 hours during phase I and flurbiprofen 100 mg every 12 hours during phase II of the study. Measurements and Main Results . Steady-state pharmacokinetic parameters were measured for each phase. Lithium trough plasma concentration (Cmin) and area under the curve were statistically significantly increased (p<0.05) when patients received flurbiprofen. Flurbiprofen also caused decreases in lithium clearance and 24-hour lithium urine excretion, although the changes did not reach statistical significance. Clinically significant increases in Cmin appeared to be associated with a greater than 1000-μg/24 hour decrease in urinary excretion of prostaglandin E2. Conclusion . Patients with clinically normal renal function may experience an increase in lithium levels with the initiation of flurbiprofen therapy. 相似文献
85.
Regulation of Neutrophil Apoptosis by Tumor Necrosis Factor-alpha : Requirement for TNFR55 and TNFR75 for Induction of Apoptosis In Vitro 总被引:7,自引:2,他引:5
86.
Neonatal Sucking Behaviors 总被引:3,自引:0,他引:3
Neonatal sucking responses or behaviors have been of great interest to researchers and clinicians since the early 1800s. Since 1960, there has been a resurgence of interest in the objective study of sucking behaviors in both the psychological and medical literature. The studies have examined both nutritive and non-nutritive sucking measurements. Sucking behaviors have been studied to understand the development of the feeding mechanism as well as to track neurobehavioral development. The relationship between sucking behaviors and behavioral organization of the newborn are considered, along with a historical perspective of sucking measurements, relevant literature on nutritive sucking, physiologic correlates, differences in breast and bottle feeding patterns, non-nutritive sucking, and factors that modify sucking organization. Implications for nursing practice will be discussed. 相似文献
87.
A model for training the trainers of child care providers that employs Vygotsky's framework of the Zone of Proximal Development is described. This efficient training mechanism proposes mentoring relationships as a means to meet the developmental needs of experienced child care professionals and improve the quality of existing child care programs.The authors would like to thank Dr. Bille Thomas and the satellite resource center directors and staff members for their work on the project. 相似文献
88.
Gale Haradon Barbara Bascom Cristiana Dragomir Virginia Scripcaru 《Occupational therapy international》1994,1(4):250-260
Infants living in an orphanage (n = 22) in Romania were assessed on the Test of Sensory Functions in Infants (TSFI). Testing of the institutionalized infants was done before and 6 months after an enriched caregiver intervention program. Results showed significant changes in areas of reactivity to tactile deep pressure, visual-tactile integration, oculomotor control, reactivity to vestibular stimulation and total test responses. No significant changes occurred in the area of adaptive motor functions. Effects of sensory deprivation resulting from institutional settings and changes that can occur from enriched caregiver environments are discussed. 相似文献
89.
Enza-Maria Valente Anjum Misbahuddin Francesco Brancati Mark R Placzek Barbara Garavaglia Sergio Salvi Andrea Nemeth Charles Shaw-Smith Nardo Nardocci Anna-Rita Bentivoglio Alfredo Berardelli Roberto Eleopra Bruno Dallapiccola Thomas T Warner 《Movement disorders》2003,18(9):1047-1051
The epsilon-sarcoglycan gene (SGCE) on human chromosome 7q21 has been reported to be a major locus for inherited myoclonus-dystonia. Linkage to the SGCE locus has been detected in the majority of families tested, and mutations in the coding region have been found recently in families with autosomal dominant myoclonus-dystonia. To evaluate the relevance of SGCE in myoclonus-dystonia, we sequenced the entire coding region of the epsilon-sarcoglycan gene in 16 patients with either sporadic or familial myoclonus-dystonia. No mutations were found. This study suggests that epsilon-sarcoglycan does not play an important role in sporadic myoclonus-dystonia and supports genetic heterogeneity in familial cases. 相似文献
90.
Gerald F. Powell MD Barbara A. Bettes PhD 《Child psychiatry and human development》1992,22(3):185-198
A controversy exists regarding the classification of nonorganic failure to thrive within the psychiatric nomenclature. There are a number of DSM-III-R diagnoses that may be applied to NOFTT, including Reactive Attachment Disorder of Infancy (RADI) and Major Depressive Disorder (MDD). The behaviors characteristic of NOFTT are symptomatic of depression, and are similar to those exhibited by infants with anaclitic depression as well as those of the adult with depression. The correspondence of the behaviours of NOFTT and the DSM-III-R criteria for Major Depression are reviewed, as are the conceptual and therapeutic reasons to view NOFTT infants as suffering from Depression. 相似文献