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101.
Keratinocyte differentiation is stimulated by activators of the nuclear hormone receptor PPARalpha 总被引:1,自引:0,他引:1
K Hanley Y Jiang SS He M Friedman PM Elias DD Bikle ML Williams KR Feingold 《Canadian Metallurgical Quarterly》1998,110(4):368-375
BACKGROUND: A patient's likelihood of dying from breast cancer or another cause can be assessed with competing risks analyses. METHODS: Data for a cohort of 678 patients with primary invasive breast cancer accrued from 1971 to 1990, updated to 1995, included cause of death (e.g., breast cancer vs. other cause). We investigated the effects of age, tumor size, nodal status, ER, PgR, and adjuvant therapy (hormones, chemotherapy, radiotherapy) on type of death and time to death for patients of all ages and for those over the age of 65 years. RESULTS: Although there were no significant univariate differences in breast cancer death rates by age group (P=0.94), more patients over the age of 65 years died from other causes (41/207 [20%] of those older than 65 years vs. 16/471 [3%] of those younger than 65 years; P <.001). In competing risks analyses, older age was associated with non-breast cancer death, whereas larger tumor size was associated with breast cancer death. PgR was positively, and nodal status negatively, associated with survival, regardless of type. In the older patient group, the competing risks analyses identified similar effects for age and tumor size; in addition, higher ER assay values were less likely to be associated with breast cancer death. CONCLUSIONS: With increased lifespan, there will be more breast cancer cases in women older than 65 years; we have shown that women in this group have more non-breast cancer deaths. It becomes important, then, to delineate differential effects of prognostic factors on competing causes of death. 相似文献
102.
JL Mankowski DL Carter JP Spelman ML Nealen KR Maughan LM Kirstein PJ Didier RJ Adams M Murphey-Corb MC Zink 《Canadian Metallurgical Quarterly》1998,153(4):1123-1130
We investigated the effects of dietary factors on the pH and the ammonia emission from slurry of growing-finishing pigs. Sixteen male hybrid pigs (80 to 90 kg BW) were allotted to one of four diets based on barley-wheat, tapioca, barley-tapioca, and sugar beet pulp. Diets were formulated to have similar NE and CP contents and a similar lysine:NE ratio. Diets differed in nonstarch polysaccharide content (NSP) and dietary electrolyte balance (dEB). Urine and feces were daily collected quantitatively in metabolism cages and mixed as a slurry at the end of the collection period. After mixing, the pH and the ammonia emission from the slurry were measured daily in a laboratory setup for 7 d at 20 degrees C. The type of diet affected the pH of the slurry and the ammonia emission (P < .001). The pH of the slurry from pigs fed the sugar beet pulp-based diet was .8 unit lower and ammonia emission was 52 to 53% lower than that of the other three diets. The low dEB and high NPS sugar beet pulp-based diet increased the VFA concentration and reduced the pH and ammonia emission from the slurry. We conclude that dietary NSP and dEB influence the pH and ammonia emission from slurry of growing-finishing pigs. 相似文献
103.
P Xia PM Bungay CC Gibson ON Kovbasnjuk KR Spring 《Canadian Metallurgical Quarterly》1998,74(6):3302-3312
The diffusion coefficients of two caged fluorescent dyes were measured in free solution and in the lateral intercellular spaces (LIS) of cultured Madin-Darby canine kidney (MDCK) cells after photoactivation by illumination with a continuous or pulsed UV laser. Both quantitative video imaging and a new photometric method were utilized to determine the rates of diffusion of the caged fluorescent dyes: 8-((4,5-dimethoxy-2-nitrobenzyl)oxy)pyrene-1,3,6-trisulfonic acid (DMNB-HPTS) and (4,5-dimethoxy-2-nitrobenzyl) fluorescein dextran (10,000 MW) (DMNB-caged fluorescein dextran). The diffusion coefficients at 37 degrees C in free solution were 3.3 x 10(-6) cm2/s (HPTS) and 0.98 x 10(-6) cm2/s (10,000 MW dextran). Diffusion of HPTS within nominally linear stretches of the LIS of MDCK cells grown on glass coverslips was indistinguishable from that in free solution, whereas dextran showed a 1.6 +/- 0.5-fold reduction in diffusivity. Measurements of HPTS diffusion within the LIS of multicellular regions also exhibited a diffusivity comparable to the free solution value. The restriction to diffusion of the dextran within the LIS may be due to molecular hindrance. 相似文献
104.
Y Takahashi CD Bucana Y Akagi W Liu KR Cleary M Mai LM Ellis 《Canadian Metallurgical Quarterly》1998,4(2):429-434
Most patients with primary IgA nephropathy (IgAN) have a significantly higher memory repertoire of IgA1-producing B lymphocytes in their bone marrow together with high plasma levels of IgA1. The connection between the mucosal immune system and the bone marrow compartment is probably based on traffic of either antigen-presenting cells (APC) or antigen-specific lymphocytes. Cytokines play an important role in the proliferation and differentiation of lymphoid cells. In order to mimic the in vivo situation as much as possible, we assessed cytokine production profiles ex vivo in 23 IgAN patients and matched controls, using lipopolysaccharide (LPS)- or phytohaemagglutinin (PHA)-stimulated whole blood (WB) cultures. Interferon-gamma (IFN-gamma), IL-2, IL-6, IL-10 and tumour necrosis factor-alpha (TNF-alpha) production in culture supernatants were determined by cytokine-specific ELISAs. Compared with controls, PHA-stimulated cultures resulted in significantly higher IL-10 (P<0.001), IL-2 (P<0.005) and IFN-gamma (P<0.001) levels in IgAN patients, but no significant differences in TNF-alpha or IL-6 levels were found. In LPS-stimulated cultures, the only significant difference (P<0.001) between the two groups was the increased IL-10 production in IgAN patients. The enhanced cytokine production in stimulated WB cultures suggests altered monocyte-related T cell responses in patients with IgAN. Increased IL-10 production may eventually result in an increased number of IgA-producing B lymphocytes in the bone marrow. In addition, high levels of endogenous IL-10 may down-regulate the effector functions of monocytes, or possibly APC in general, and consequently the IgA response at the mucosal level. 相似文献
105.
TR Mahalingam S Vijayalakshmi RK Prabhu A Thiruvengadasami CK Mathews KR Shanmugasundaram 《Canadian Metallurgical Quarterly》1997,57(3):191-206
Blood is one of the widely used specimens for biological trace element research because of its biological significance and ease of sampling. We have conducted a study of the blood of the Kalpakkam township population for trace and minor elements. For this purpose, analytical methods have been developed and standardized in our laboratory for the elemental analysis of blood plasma and red cells. Inductively coupled plasma-mass spectrometry (ICP-MS), a relatively new technique, has been applied for the analysis of trace elements. Details regarding spectral interference and matrix interference encountered in the analysis of blood and the methods of correcting them have been discussed. Flame atomic absorption spectrometry (AAS)/atomic emission spectrometry (AES) has been applied for the determination of minor elements. Precision and accuracy of these methods have also been discussed. 相似文献
106.
107.
Aluminum (Al) transport across yeast cells was studied using Dy(NO3)3 as a shift reagent by 27Al-NMR spectroscopy. The results showed that (a) Al enters the yeast cells at 15 min and over a period of time, within 4 h, an equilibrium sets in between outside and inside Al; (b) citrate does not favor Al going into the yeast cells at pH 5.0; and (c) EDTA brings out all the Al that has entered the yeast cells. 相似文献
108.
PB Kruger S Mathews M Katz KR Aggarwala S Nowbotsing 《Canadian Metallurgical Quarterly》1997,37(18):2511-2526
Accommodation was monitored continuously under open-loop conditions while subjects viewed a sinusoidally oscillating sine-wave grating (0.2 Hz; +/- 1 D; 2.7 c/d; 0.56 contrast) in a Badal optometer. The target was illuminated by monochromatic light (590 nm) or white light (3000 K) with longitudinal chromatic aberration (LCA) normal, doubled, neutralized and reversed. Subjects (12) accommodated well in white light with LCA normal and doubled (mean gains = 0.85 and 0.94), gain was reduced in the neutralized condition (0.54), in monochromatic light (0.43), and especially when LCA was reversed (0.30). The results suggest that accommodation responds to changes in the relative contrast of spectral components of the retinal image and perhaps to the vergence of light. 相似文献
109.
110.