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排序方式: 共有484条查询结果,搜索用时 19 毫秒
61.
Molecular cloning, chromosomal location, and tissue-specific expression of the murine cathepsin G gene 总被引:5,自引:1,他引:5
Heusel JW; Scarpati EM; Jenkins NA; Gilbert DJ; Copeland NG; Shapiro SD; Ley TJ 《Blood》1993,81(6):1614-1623
We previously have characterized a cluster of genes encoding cathepsin G (CG) and two other CG-like hematopoietic serine proteases, CGL-1 and CGL-2, on human chromosome 14. In this report, we clone and characterize a novel, related murine hematopoietic serine protease gene using human CG (hCG) cDNA as the probe. This murine gene spans approximately 2.5 kb of genomic DNA, is organized into five exons and four introns, and bears a high degree of homology to hCG at both nucleic acid (73%) and deduced amino acid (66%) levels. The predicted cDNA contains an open reading frame of 783 nucleotides that encodes a nascent protein of 261 amino acids. Processing of a putative signal (pre) peptide of 18 residues and an activation (pro) dipeptide would generate a mature enzyme of approximately 27 Kd that has an estimated pI of 12.0. Conserved residues at His44, Asp88, and Ser181 form the characteristic catalytic triad of the serine protease superfamily. The gene is tightly linked to the CTLA-1 locus on murine chromosome 14, where the serine protease genes mCCP1-4 are clustered. Expression of this gene is detected only in the bone marrow and is restricted to a small population of early myeloid cells. These findings are consistent with the identification of the gene encoding murine CG. 相似文献
62.
Characterization of CD33 as a new member of the sialoadhesin family of cellular interaction molecules 总被引:14,自引:6,他引:14
CD33 is a member of the Ig superfamily that is restricted to cells of the myelomonocytic lineage but whose functions and binding properties are unknown. It shares sequence similarity with sialoadhesin, CD22, and the myelin-associated glycoprotein, which constitute the Sialoadhesin family of sialic acid-dependent cell adhesion molecules. In the present study, we show that CD33 is a fourth member of this family. As a model for sialic acid-dependent binding, human erythrocytes were derivatized with N-acetylneuraminic acid (NeuAc) in different linkages. A recombinant soluble form of CD33, Fc-CD33, bound red blood cells with a specificity similar to that of sialoadhesin, preferring NeuAc alpha 2,3Gal in N- and O-glycans over NeuAc alpha 2,6Gal in N-glycans. Fc- CD33 also bound selectively to the myeloid cell lines HL-60 and U937. However, CD33 was unable to mediate cell binding after transient expression in COS cells, despite high levels of surface expression. Pretreatment of the CD33-transfected cells with sialidase rendered them capable of mediating sialic acid-dependent binding. These results show that CD33 can function as a sialic acid-dependent cell adhesion molecule and that binding can be modulated by endogenous sialoglycoconjugates when CD33 is expressed in a plasma membrane. 相似文献
63.
DM Blischak SD Shah LJ Lombardino K Chiarella 《Disability and rehabilitation》2013,35(21-22):1295-1304
Purpose: To examine the effects of phoneme-grapheme correspondence and phonemic awareness instruction on the encoding abilities of three pre-reading children with severe speech impairment (SSI). Method: Using a single subject multiple baseline design across behaviours and participants, children received phoneme-grapheme awareness instruction followed by instruction in segmenting, manipulating, and encoding consonant-vowel-consonant (CVC) pseudowords. Results: Generalization occurred to encoding of novel CVC pseudo- and real words for two of the three participants. Conclusions: Results suggest that phoneme-grapheme correspondence and phonemic awareness instruction is effective in developing encoding skills in children with SSI. Findings are consistent with those for other at-risk children. 相似文献
64.
Magnetization transfer contrast: MR imaging of the knee 总被引:1,自引:0,他引:1
65.
66.
67.
Symptom burden, quality of life, advance care planning and the potential value of palliative care in severely ill haemodialysis patients. 总被引:7,自引:4,他引:3
Steven D Weisbord Sharon S Carmody Frank J Bruns Armando J Rotondi Lewis M Cohen Mark L Zeidel Robert M Arnold 《Nephrology, dialysis, transplantation》2003,18(7):1345-1352
BACKGROUND: There has been little research on the potential value of palliative care for dialysis patients. In this pilot study, we sought (i) to identify symptom burden, health-related quality of life (HRQoL) and advance directives in extremely ill haemodialysis patients to determine their suitability for palliative care and (ii) to determine the acceptability of palliative care to patients and nephrologists. METHODS: Nineteen haemodialysis patients with modified Charlson co-morbidity scores of > or =8 were recruited. Each completed surveys to assess symptom burden, HRQoL and prior advance care planning. Palliative care specialists then visited patients twice and generated recommendations. Patients again completed the surveys, and dialysis charts were reviewed to assess nephrologists' (i) compliance with recommendations and (ii) documentation of symptoms reported by patients on the symptom assessment survey. Patients and nephrologists then completed surveys assessing their satisfaction with palliative care. RESULTS: Patients reported 10.5 symptoms, 40% of which were noted by nephrologists in patients' charts. HRQoL was significantly impaired. Thirty-two percent of patients had living wills. No differences were observed in symptoms, HRQoL or number of patients establishing advance directives as a result of the intervention. Sixty-eight percent of patients and 76% of nephrologists rated the intervention worthwhile. CONCLUSIONS: Extremely ill dialysis patients have marked symptom burden, considerably impaired HRQoL and frequently lack advance directives, making them appropriate candidates for palliative care. Patients and nephrologists perceive palliative care favourably despite its lack of effect in this study. A more sustained palliative care intervention with a larger sample size should be attempted to determine its effect on the care of this population. 相似文献
68.
Renal localization of gallium-67 citrate 总被引:1,自引:0,他引:1
69.
Effect of parental age on fertilization and pregnancy characteristics in couples treated by intracytoplasmic sperm injection 总被引:11,自引:5,他引:6
Spandorfer SD; Avrech OM; Colombero LT; Palermo GD; Rosenwaks Z 《Human reproduction (Oxford, England)》1998,13(2):334-338
The purpose of this study was to investigate any influence of maternal
and/or paternal age on gamete characteristics and pregnancy outcomes in
intracytoplasmic sperm injection (ICSI) cycles. In all, 821 consecutive
ICSI cases were analysed retrospectively. While a significant linear
decline in semen volume was detected, no significant differences in the
concentration, motility or morphology of the spermatozoa were found with
paternal ageing. A significant decline in the number of oocytes retrieved
and the number of mature oocytes obtained was found with advancing maternal
age. An increase in the occurrence of digyny was noted with parental
ageing, while no difference in single or bipronuclear fertilization was
found. Older women had a decreased incidence of single pronucleus formation
and an increase in digyny, but no significant difference in the percentage
of oocytes that underwent two-pronuclear fertilization was detected with
regard to maternal ageing. Pregnancy outcomes were not influenced by the
age of the male partner, while a strong negative correlation was found with
maternal ageing. To better analyse male partner ageing as a factor
affecting pregnancy outcome, we analysed a subgroup of patients with a
female partner aged <35 years who underwent ICSI. No paternal influence
on ICSI pregnancy outcome was found in this subgroup of patients. We
conclude that the influence on pregnancy outcome after ICSI is related
mostly to maternal and not paternal age.
相似文献
70.