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991.
992.
993.
RE Kibbelaar JW Mulder EJ Dreef H van Kamp WE Fibbe JW Wessels GC Beverstock HL Haak PM Kluin 《Canadian Metallurgical Quarterly》1993,82(3):904-913
Fluorescence in situ hybridization (FISH) is a powerful tool for detection of numerical and structural chromosomal aberrations. We have compared conventional banding techniques and FISH for the detection of monosomy 7 (-7) and trisomy 8 (+8) in 89 patients with myeloid malignancies. Of these patients, 21 had -7, 30 had +8, four had both, and 34 had no aberrations or aberrations other than -7 or +8 as assessed by banding techniques. Sequential samples were available in 23 patients. Alphoid DNA probes specific for chromosomes no. 7 and 8 were used for FISH. As controls, 10 normal bone marrow (BM) samples were hybridized with the chromosomes no. 7 and 8 probes, and in addition all tumor samples were hybridized with a chromosome no. 1 specific probe. The cut-off value for -7 was 18% one-spot cells, and for +8 was 3% three-spot cells. FISH analysis of 44 samples with -7 or +8, and at least 10 metaphases evaluated, showed that the proportions of aberrant metaphase cells mirrored the interphase clone sizes. Most samples with nonclonal metaphase aberrations, including those with only a few metaphases, had increased numbers of aberrant interphase cells: 20% to 80% for -7, and 3% to 43% for +8. Interphase cytogenetics of the 34 samples without -7 or +8 did not show significant cell populations with -7 or +8. In four patients, -7 or +8 could not be confirmed by FISH due to additional structural aberrations, marker chromosomes, or wrongly interpreted banding results. As FISH will be used more and more in cytogenetic diagnosis, clinical follow-up, and therapy monitoring, it will be necessary to standardize FISH procedures and supplement the Standing Committee on Human Cytogenetic Nomenclature (ISCN) definitions of a clone with criteria specifically for in situ hybridization. 相似文献
994.
Bilateral cataracts were detected in a group of aquarium-raised tilapia (Sarotherodon mossambicus). Vision impairment was manifested as random swimming into objects, but the fish appeared to function normally otherwise. Most of the lens was opaque, with the outer extent of the cortex and subcapsular region remaining transparent. Skeletal abnormalities, ie, deformed fins, abnormal jaws, and curvature of the spine, were observed in affected individuals. Histologically, there was progressive degeneration of the cataractous portion as the affected fish matured. Preliminary breeding experiments indicated that the condition may be inherited. 相似文献
995.
V Villagrasa L Berto J Cortijo M Perpina C Sanz EJ Morcillo 《Canadian Metallurgical Quarterly》1997,29(4):605-609
1. Erythromycin (2-100 micrograms ml-1) produced a concentration-related inhibition of superoxide generation and elastase release induced by in vitro exposure of human polymorphonuclear leukocytes (PMNs) to the chemotactic peptide N-formylmethionyl-leucyl-phenylalanine (FMLP; 30 nM). 2. By contrast, erythromycin (100 micrograms ml-1) did not alter the leukotriene B4 production elicited by FMLP (30 nM; in the presence of thimerosal 20 microM) or the intracellular calcium changes promoted by FMLP (30 nM; in the absence or presence of thimerosal 20 microM). 3. These results indicate that by reducing chemoattractant-triggered release of oxidative and proteolytic mediators from human PMNs, erythromycin may have clinically useful antiinflammatory effects. 相似文献
996.
While it is generally recognized that NPs offer affordable, quality health care, few studies have measured outcomes of clients who seek primary care services from NPs. This pilot study describes the outcomes of children with otitis media who received care from NPs employed in an academic nursing center. Outcome measurements included issues related to timing, level of analysis, and attribution. Parents of 27 children participated in a telephone survey consisting of seven questions relating to the care their children received from NPs and their recovery path. Although every respondent reported having a positive visit at the nursing center, concerns for NPs surfaced during the process of measuring outcomes. This study emphasizes the need for measuring outcomes in nursing clinics and demonstrates one way to measures client outcomes, revealing both general health care and specific nursing practice implications. 相似文献
997.
Transport by discrete vesicular carriers is well established at least in part because of recent discoveries identifying key protein mediators of vesicle formation, docking, and fusion. A general mechanism sensitive to N-ethylmaleimide (NEM) is required for the transport of a divergent group of vesicular carriers in all eukaryotes. Many endothelia have an abundant population of non-coated plasmalemmal vesicles or caveolae, which have been reported with considerable controversy to function in transport. We recently have shown that like other vesicular transport systems, caveolae-mediated endocytosis and transcytosis are inhibited by NEM (Schnitzer, J. E., Allard, J., and Oh, P. (1995) Am. J. Physiol. 268, H48-H55). Here, we continue this work by utilizing our recently developed method for purifying endothelial caveolae from rat lung tissue (Schnitzer, J. E., Oh, P., Jacobson, B. S., and Dvorak, A. M. (1995) Proc. Natl. Acad. Sci. U. S. A. 92, 1759-1763) to show that these caveolae contain key proteins known to mediate different aspects of vesicle formation, docking, and/or fusion including the vSNARE VAMP-2, monomeric and trimeric GTPases, annexins II and VI, and the NEM-sensitive fusion factor NSF along with its attachment protein SNAP. Like neuronal VAMPs, this endothelial VAMP is sensitive to cleavage by botulinum B and tetanus neurotoxins. Caveolae in endothelium are indeed like other carrier vesicles and contain similar NEM-sensitive molecular machinery for transport. 相似文献
998.
JE Cooley RA Briggaman DJ Cronce AJ Banes EJ O'Keefe 《Canadian Metallurgical Quarterly》1996,107(6):877-881
The blisters in the inherited disorder, Hailey-Hailey disease, may be caused by defective epidermal junctional complexes. We evaluated these structural complexes in vivo and in vitro. We induced a vesicular lesion in the apparently normal skin of a patient with Hailey-Hailey disease and studied a biopsy of this lesion by transmission electron microscopy. To determine whether acantholysis was related to a defect in the number or assembly of intercellular junctions, we cultured Hailey-Hailey disease keratinocytes in medium containing 0.1 mM Ca2+ and increased the [Ca2+] to 1.1 mM in order to induce assembly of cell-cell junctions. Keratinocytes were examined by double immunofluorescence with antibodies to the desmosome protein, desmoplakin, and the adherens junction protein, vinculin, at intervals after the increase in [Ca2+]. Characteristic Hailey-Hailey disease histopathology was observed by electron microscopy of the patient's skin after trauma, but we found no splitting of desmosomes. Based on the location, intensity, and rate of change of immunofluorescent staining, Hailey-Hailey and normal keratinocytes did not differ in their ability to assemble desmosomes and adherens junctions. Furthermore, we observed no significant morphologic differences between normal and Hailey-Hailey keratinocytes cultured in low and high [Ca2+]-containing media; Hailey-Hailey cells contained abundant normal-appearing desmosomes in 1.1 mM [Ca2+]. Since Hailey-Hailey disease keratinocytes can assemble normal-appearing adherens junctions and desmosomes in vitro, the functional defect may not lie in assembly of cell-cell adhering junctions, or additional perturbation may be required to expose the defect. 相似文献
999.
EJ Norval 《Canadian Metallurgical Quarterly》1998,30(2):209-211
We studied basic sleep changes in pregnant rats in order to understand how pregnancy alters sleep. In the rat, pregnancy increased nocturnal nonREM sleep across the entire period but increased REM sleep only in the early period. By the end of pregnancy, diurnal sleep was decreased, showing that pregnancy in rats causes biphasic sleep changes as it does in humans. Termination of pregnancy returned the enhanced sleep to baseline as in the estrous cycle. Therefore, significant changes in the pattern of sleep occurred during pregnancy in rats, suggesting that the animal model may contribute to understanding the mechanism of sleep disorders related to human pregnancy. 相似文献
1000.
KA Stolp-Smith EJ Atkinson ME Campion PC O'Brien M Rodriguez 《Canadian Metallurgical Quarterly》1998,50(6):1594-1600
OBJECTIVE: The authors sought to determine acute ambulatory- and hospital-billed charges for the Olmsted County, Minnesota Multiple Sclerosis (MS) Disability Prevalence Cohort and compare them to those incurred by the general population. METHODS: Billed charges for 155 people with clinically definite or laboratory-supported MS were compared with those of age- and gender-matched non-MS controls. Billing data, including all inpatient and outpatient acute and rehabilitative medical care charges over a 5-year period surrounding a December 1, 1991 prevalence date, were analyzed. Data were correlated with level of disability using the Minimal Record of Disability for MS. RESULTS: Median total annual billed charges for most individuals with MS, including those with less severe ($1,277) and relapsing-remitting illness ($1,348), did not differ from those for controls ($1,327, p=0.075). Only those with severe MS (22.6%) had median annual medical charges higher than controls ($5,440, p < 0.001). Male patients with MS had higher median annual total charges ($2,353) than male controls ($762, p=0.003). Total charges for female patients with MS ($1,440) were not different from those for female controls ($1469). Median annual outpatient charges were 15% more for the MS group ($1,418) than for controls ($1,231). Patients with MS had a mean of 0.2 hospital admissions annually compared with 0.1 annual admissions per control patient. Among variables collected on persons with MS, the Expanded Disability Status Scale was the strongest predictor of level of charges (p < 0.001). CONCLUSION: Acute ambulatory- and hospital-billed charges for most patients with MS do not differ from those of the general population. 相似文献