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Acidosis, alkalosis, and aqueous humor dynamics in rabbits 总被引:1,自引:0,他引:1
T Krupin CJ Oestrich J Bass SM Podos B Becker 《Canadian Metallurgical Quarterly》1977,16(11):997-1001
Systemic acidosis induced by intravenous administration of hydrochloric acid lowered intraocular pressure in unanesthetized rabbits. Aqueous humor flow was reduced by approximately 50%, as measured by the iodide method and as calculated from tonographic data. Outflow facility, episcleral venous pressure, plasma osmolality, blood pressure, pulse, and body temperature were not altered by systemic acidosis. Systemic alkalosis induced by intravenously administered sodium bicarbonate was associated with an increased intraocular pressure. Aqueous humor flow following systemic alkalosis was increased by approximately 100%, as measured by the iodide method and as calculated from tonographic data. Alkalosis was not associated with alterations in outflow facility, episcleral venous pressure, plasma osmality, blood pressure, pulse, or rectal temperature. 相似文献
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SM Bunting 《Canadian Metallurgical Quarterly》1997,18(5):523-537
Women's mental health has been linked to oppression and to oppressive practices in health care. Feminist approaches to health care delivery and research have been suggested as a remedy for the subtle and overt oppression faced by women, and many nurses have used feminist principles to conduct and report their research and to critique existing studies. Though nursing authors have identified useful feminist guides for conducting and reporting research, few examples of the practice of feminist critiques of research are available in the nursing literature. This analysis synthesizes and adapts feminist principles from nursing literature and presents a feminist model to review selected nursing research reports of women with human immunodeficiency virus (HIV). A convenience sample of eight articles from nursing journals was examined for statements or implications that the author(s) (a) perceived the purposes of the study as benefiting women, (b) demonstrated an awareness of the structures and policies that oppress women, (c) were sensitive to issues of diversity, (d) were committed to social change, and (e) recognized the female participants' strengths. The selected articles were found to meet many of the feminist criteria, although these principles were not always explicitly addressed in the articles. 相似文献
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SM Carroll CM Carroll RW Stremel SJ Heilman GR Tobin JH Barker 《Canadian Metallurgical Quarterly》1997,63(4):1034-1040
BACKGROUND: Cardiomyoplasty (CMP) uses the latissimus dorsi muscle (LDM) to assist the heart in cases of cardiac failure. Distal ischemia and necrosis of the LDM is a recognized complication of CMP that can reduce distal muscle function and the mechanical effectiveness of CMP. METHODS: Canine (n = 9) LDMs were subjected to a 10-day period of vascular delay followed by a simulated CMP. Two weeks after simulated CMP (corresponding to the healing delay between CMP and the onset of LDM stimulation used in the clinical setting), LDM perfusion was measured in the distal, middle, and proximal segments of the muscle, and circumferential (distal and middle squeezing muscle function) and longitudinal (proximal pulling muscle function) force generation and fatigue rates were measured. The results were compared with the contralateral nondelayed simulated CMP. RESULTS: Muscle perfusion was significantly (p < 0.05) greater in the distal and middle segments of vascular-delayed LDMs. Circumferential muscle force generation and fatigue rates were significantly (p < 0.05) improved in the vascular-delayed LDMs. CONCLUSIONS: Vascular delay can significantly improve LDM perfusion and function in a model that closely reflects clinical CMP, and the use of vascular delay may improve clinical outcomes in CMP. 相似文献
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BM Gburek TA Kollmorgen J Qian SM D''Souza-Gburek MM Lieber RB Jenkins 《Canadian Metallurgical Quarterly》1997,157(1):223-227
We previously reported a HPLC assay method using fluorimetric detection for the simultaneous determination of urinary N2-(3-aminopropyl)biopterin (oncopterin, a natural pteridine newly found in urine from cancer patients), biopterin and neopterin. We now have observed that an unknown substance, which may be derived from methotrexate, in urine from a patient with stomach cancer interfered with the assay of oncopterin and demonstrated that oncopterin could be completely separated from the unidentified substance by HPLC using a Nucleosil 100-5SA strong cation-exchange column. Furthermore, oncopterin was not detectable by this HPLC-fluorimetric method in urine samples from patients with stomach cancer who were not treated with methotrexate. The content of urinary oncopterin from cancer patients is supposed to be very low, with less than 1 mumol/mol creatinine. The present results indicate that the peak found with elution from the C18 column was a methotrexate-derived compound and co-eluted with the analyte oncopterin. 相似文献
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