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61.
MG Netea PN Demacker N de Bont OC Boerman AF Stalenhoef JW van der Meer BJ Kullberg 《Canadian Metallurgical Quarterly》1997,65(7):2663-2667
Recent studies have suggested the use of lipoproteins as an adjuvant treatment of lethal gram-negative infections. However, other important microorganisms for the etiology of sepsis, such as Candida species, grow better in lipid-rich environments. We investigated the effect of hyperlipoproteinemia on systemic candidiasis in low-density-lipoprotein-receptor-deficient (LDLR-/-) mice, in which the loss of the receptor results in a seven- to ninefold-higher plasma LDL level than that in their wild-type littermates (C57BL/6J). LDLR-/- mice died earlier, and the outgrowth of Candida albicans in the kidneys and livers of LDLR-/- mice was significantly higher compared with that of controls. After infection, circulating cytokine concentrations were significantly higher in LDLR-/- mice. In vitro, C. albicans grew better in plasma samples of LDLR-/- mice than in control plasma samples and peritoneal macrophages of LDLR-/- mice challenged with heat-killed C. albicans produced more cytokines than did those of controls. This latter phenomenon was probably due to increased binding of yeast cells to macrophages of LDLR-/- mice. These data suggest that hyperlipoproteinemia is deleterious in systemic candidiasis. 相似文献
62.
OBJECTIVE: 1) To examine the ordering of head CT scans in elder patients with delirium and cognitive impairment; and 2) to report CT scan findings associated with these conditions. METHODS: This was a 2-part study. Part 1 was a prospective, observational study of 560 adults > 70 years of age evaluated at 3 separate EDs using a 200-hour stratified sampling process at each ED. During Part 1, the frequencies of specific findings (i.e., delirium, impaired consciousness, and impaired cognition) and CT scan rates for these groups were determined. Part 2 was a retrospective analysis of CT scan reports and medical records (n = 279) for patients > 70 years of age in the prospective sample (n = 79) and from a sample (n = 200) of CT scans obtained at a fourth ED. Part 2 examined clinical findings detected in the ED to determine those factors that were associated with acute findings on CT scan. RESULTS: Part 1: There were 333 (59.4%) patients prospectively classified as having impaired cognition, impaired consciousness, or delirium; 79 (23.7%) of these patients had a head CT scan. Of these 3 groups, delirious patients were more frequently scanned (p < 0.001). Part 2: Of 279 CT scans, 42 (15.0%) were positive for an acute condition (hemorrhage, hematoma, space-occupying lesion, infarct). Of 42 positive scans, 40 (95.1%) were found in the 102 (36.6%) patients with either impaired consciousness or a new focal neurologic finding detected in the ED. CONCLUSIONS: Considerable variability in ED CT scan ordering exists for elder patients with neurologic findings. Impaired consciousness and/or new focal neurologic signs are associated with acute findings on CT scan in elder patients. Acute CT abnormalities are uncommon in elder ED patients with other neurologic findings. Additional prospective evaluation is warranted prior to guideline development for CT scans in this patient population. 相似文献
63.
We sought to estimate the impact of maternal HIV testing and prenatal care on the potential to reduce vertical transmission through zidovudine (AZT) use by HIV-infected mothers. We evaluated the prepartum maternal HIV diagnosis rate, prenatal care, disease stage, and vertical transmission rate (from a two-part mixture model) using New York State Medicaid and vital statistics data for HIV-infected mothers and their singletons in 1985-90. We used published data to estimate the effect of AZT on vertical transmission and expert input to define other parameters for the model. Our HIV-infected (N = 1514) had a vertical transmission rate of 27.0%. HIV was diagnosed prepartum for 39.5% of women in 1990. Transmission would have been 22.2% if AZT had been taken only by the subset of women diagnosed prepartum with HIV and receiving prenatal care by 34 weeks gestation (86.7%). Transmission would have dropped to 11.2% if all women had been diagnosed prepartum with HIV and received adequate prenatal care. The observed deficiencies in prenatal care and maternal HIV diagnosis rates in this Medicaid population-based cohort must be addressed to realize the promise of AZT to reduce vertical transmission. 相似文献
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65.
BJ Cardinal 《Canadian Metallurgical Quarterly》1995,80(1):255-258
The readability levels of 10 articles each from the Journal of Health Education, Journal of Physical Education, Recreation and Dance, Research Quarterly for Exercise and Sport, and Strategies: A Journal for Physical and Sport Educators were estimated. On average, the 40 articles were written at the college junior level (M = 14.9, SD = 1.6); however, significant between-journal differences were found, with between-journal effect sizes ranging from 0.36 to 3.64. 相似文献
66.
BJ van Herendael 《Canadian Metallurgical Quarterly》1995,22(3):391-408
Good instruments and proper training enable one to make an accurate diagnosis and to operate successfully to correct an intrauterine abnormality. There are a limited number of instruments for diagnostic and operative hysteroscopy so that the gynecologist can quickly become acquainted with the most appropriate instruments for each clinical situation. 相似文献
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GA Gerhardt WA Cass J Hudson M Henson Z Zhang A Ovadia BJ Hoffer DM Gash 《Canadian Metallurgical Quarterly》1996,66(2):579-588
Translational recruitment of maternal mRNAs is an essential process in early metazoan development. To identify genes required for this regulatory pathway, we have examined a collection of Drosophila female-sterile mutants for defects in translation of maternal mRNAs. This strategy has revealed that maternal-effect mutations in the cortex and grauzone genes impair translational activation and cytoplasmic polyadenylation of bicoid and Toll mRNAs. Cortex embryos contain a bicoid mRNA indistinguishable in amount, localization, and structure from that in wild-type embryos. However, the bicoid mRNA in cortex embryos contains a shorter than normal polyadenosine (poly(A)) tail. Injection of polyadenylated bicoid mRNA into cortex embryos allows translation demonstrating that insufficient polyadenylation prevents endogenous bicoid mRNA translation. In contrast nanos mRNA, which is activated by a poly(A)-independent mechanism, is translated in cortex embryos, indicating that the block in maternal mRNA activation is specific to a class of mRNAs. Cortex embryos are fertilized, but arrest at the onset of embryogenesis. Characterization of grauzone mutations indicates that the phenotype of these embryos is similar to cortex. These results identify a fundamental pathway that serves a vital role in the initiation of development. 相似文献