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991.
Modern cataract surgery is constantly evolving and improving in terms of lens material and design. Researchers and physicians strive to obtain better refractive correction with smaller wound size and minimizing host cell response to limit the proliferation of lens epithelial cells leading to opacification of the lens capsule. Intraocular lens material varies in water content, refractive index, and tensile strength. Intraocular lens design has undergone revisions to prohibit lens epithelial cell migration and reflection of internal and external light. The evolution of intraocular lens and extracapsular cataract surgery has lead to faster postoperative recovery and better visual outcomes. 相似文献
992.
993.
994.
Evaluation of a non-breath-hold MR cholangiography technique 总被引:15,自引:0,他引:15
Macaulay SE; Schulte SJ; Sekijima JH; Obregon RG; Simon HE; Rohrmann CA Jr; Freeny PC; Schmiedl UP 《Radiology》1995,196(1):227
995.
Although the proliferative effects of hematopoietic cytokines on erythroid progenitors are well known, parameters that influence the initiation of expression of specialized or lineage-restricted genes are not clear. We have studied the acquisition of erythroid-differentiative features from enriched populations of human early erythroid progenitors (burst-forming unit-erythroid [BFUe]) in suspension culture and the influence of several cytokines on this process. In suspension cultures containing no erythropoietin (Epo), we have found that kit ligand (KL) in synergy with interleukin-3 not only increases the proliferation of cells and of progenitors but also consistently amplifies a population of cells that contain globin within 1 week. Our experiments suggest that neither extraneously provided nor endogenously produced Epo is critical for the generation of globin-synthesizing cells. Globin- producing cells generated mostly from late BFUe or pre-CFUe with a CD34- /EP-1+ phenotype in this system do not all express a well-coordinated erythroid program accompanied by heme or glycophorin A expression and most die maintaining an immature state. Therefore, conditions that are responsible for initiation of globin expression in these cells are not sufficient to carry them to terminal maturation. The data point to an expanded target cell population for KL, as they suggest an influence of KL on survival and/or amplification of late erythroid cells previously thought to be influenced only by Epo. Our results in aggregate are of relevance to the physiology of normal erythropoiesis and the role of Epo and KL in the initial stages of lineage-restricted gene expression. In addition, they provide insight into the understanding of anemia in W and Steel mutants in which expansion of the late erythroid progenitor pool, normally dependent on the synergistic action of KL and Epo, is curtailed. 相似文献
996.
997.
A clinical, cytogenetic and molecular study of ten probands with supernumerary inv dup (15) marker chromosomes 总被引:1,自引:0,他引:1
Ten probands with moderate to severe developmental delay were found to have a supernumerary inv dup (15) chromosome. These patients and their families were studied by both cytogenetic and molecular methods. Cytogenetic polymorphisms associated with the 15p short arm suggested a maternal derivation for the marker chromosome in all informative cases. One marker was directly maternally inherited. Molecular analysis employing Southern blotting and polymerase chain reaction (PCR) of microsatellite repeats demonstrated the presence of extra alleles in the 15q11q13 region. All ten of the probands demonstrated an extra band at one or more locus without recourse to densitometry. All of the inv dup (15) markers were comparable in size to a G group chromosome but there were differences in the positions of the breakpoints in 15q. There was an inconsistent relationship between marker size, gene dosage and severity of phenotype. 相似文献
998.
999.
Mortality in Systemic Sclerosis (Scleroderma) 总被引:10,自引:0,他引:10
LEE P; LANGEVITZ P; ALDERDICE CA; AUBREY M; BAER PA; BARON M; BUSKILA D; DUTZ JP; KHOSTANTEEN I; PIPER S; RAMSDEN M; ROSENBACH TO; SUKENIK S; WILKINSON S; KEYSTONE EC 《QJM : monthly journal of the Association of Physicians》1992,82(2):139-148
Two hundred and thirty-seven patients with systemic sclerosiswere followed prospectively in a scleroderma clinic. The overall3, 6, and 9-year survival rates were 86, 76 and 61 per centrespectively. Renal, cardiac and pulmonary disease, and olderage at enrolment were adverse prognostic factors associatedwith reduced survival. There were no significant differencesin survival between males and females or in patients with restrictedcompared to those with diffuse skin thickening. Death from systemicsclerosis was most frequently due to pulmonary hypertension,with fewer than expected deaths from renal or cardiac causes.Twenty-eight per cent of deaths were due to causes unrelatedto systemic sclerosis, most commonly cancer and ischaemic heartdisease, and in older patients 相似文献
1000.