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91.
92.
Inorganic phosphate has been known to assist red blood cell maintenance of ATP and in the presence of inosine to assist in the maintenance of 2,3-DPG. High concentrations of phosphate, while helping ATP maintenance, were found to be deleterious to 2,3-DPG maintenance in CPD- adenine preservatives. However, in the presence of inosine, concentrations of phosphate as high as 10 mM were advantageous to 2,3- DPG maintenance. The present study extends the observations on ATP and 2,3-DPG maintenance in CPD-adenine-inosine preservatives from the previous 10 mM to 20 mM phosphate. A high phosphate (20 mM) effect has been seen as improved maintenance of 2,3-DPG levels during the fifth and sixth weeks of storage of whole blood at 4C. This supports the previously reported observation of improved maintenance of 2,3-DPG in a 10 mM phosphate preservative. This is ten times the 2 mM phosphate concentration in CPD-adenine. In the low phosphate preservative (2 mM), 2,3-DPG maintenance is less than that in all of the higher phosphate preservatives after the second week of storage. ATP concentrations in this experiment show good maintenance throughout six weeks of storage. 相似文献
93.
Inhaled nitric oxide (INO) is a colorless, odorless gas that is also a potent pulmonary vasodilator. When given via the inhaled route it is a selective pulmonary vasodilator. INO is approved by the United States Food and Drug Administration (FDA) for the treatment of term and near-term neonates with hypoxemic respiratory failure associated with clinical or echocardiographic evidence of pulmonary arterial hypertension. A systematic review of the literature was conducted with the intention of making recommendations related to the clinical use of INO for its FDA-approved indication. Specifically, we wrote these evidence-based clinical practice guidelines to address the following questions: (1) What is the evidence for labeled use? (2) What are the specific indications for INO for neonates with acute hypoxemic respiratory failure? (3) Does the use of INO impact oxygenation, mortality, or utilization of extracorporeal membrane oxygenation (ECMO)? (4) Does INO affect long-term outcomes? (5) Is INO cost-effective therapy? (6) How is the appropriate dosing regimen and dose response to INO established? (7) How is the dose of INO titrated and weaned? (8) Which INO delivery system should be used? (9) How should INO be implemented with different respiratory support devices? (10) What adverse effects of INO should be monitored, and at what frequency? (11) What physiologic parameters should be monitored during INO? (12) Is scavenging of gases necessary to protect the caregivers? Using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) scoring system, 22 recommendations are developed for the use of INO in newborns. 相似文献
94.
Clinical pharmacology of imipenem and cilastatin in premature infants during the first week of life. 下载免费PDF全文
M D Reed R M Kliegman T S Yamashita C M Myers J L Blumer 《Antimicrobial agents and chemotherapy》1990,34(6):1172-1177
The first-dose and multidose pharmacokinetics of imipenem and cilastatin were evaluated in 41 premature infants during their first week of life. Premature infants (gestational age, less than or equal to 37 weeks) were assigned to receive 10-, 15-, 20-, or 25-mg/kg doses of imipenem-cilastatin (1:1) as a single- or multiple-dose regimen. A total of 39 infants received a single dose, whereas 18 infants received multiple doses. No differences were observed in pharmacokinetic parameter estimates for either agent relative to the dose administered or infant body weight; thus, the data were pooled. Elimination half-life, steady-state volume of distribution, and body clearance averaged 2.5 h, 0.5 liter/kg, and 2.5 ml/min per kg, respectively, for imipenem and 9.1 h, 0.4 liter/kg, and 0.5 ml/min per kg, respectively, for cilastatin. Similar values for these parameter estimates were observed after multidose administration, although substantial accumulation of cilastatin in serum was observed. A total of 21% of the imipenem and 43% of the cilastatin were excreted unchanged in the urine over a 12-h collection period. Corresponding renal clearances averaged 0.4 and 0.2 ml/min per kg for imipenem and cilastatin, respectively. Substantial differences were observed in the route by which imipenem was cleared from the body compared with data from adult volunteers. These data suggest that infants should receive an imipenem dose of 20 mg/kg administered every 12 h for the treatment of bacterial infections outside the central nervous system. 相似文献
95.
Penelope S. Myers 《Aphasiology》2013,27(10-11):913-918
Research and clinical efforts aimed at understanding and improving the communication impairments associated with acquired right hemisphere damage (RHD) are hampered by lack of a formal definition or label. This paper addresses that issue in light of the recent proposal by Joanette and Anslado (1999a, b) that RHD communication disorders be called "Pragmatic Aphasia". Underlying assumptions regarding the use of the term aphasia to describe these deficits and the concept that pragmatics is inherent to language are questioned. The potential value of "pragmatics" as it relates to communicative intents, and its potential application to a definition of RHD communication impairments are also explored. 相似文献
96.
Transvaginal sonographic appearance of thrombosed uterine arteries after uterine artery embolization: the "white snake" sign 总被引:2,自引:0,他引:2
PURPOSE: The aim of this prospective study was to describe the appearance of thrombosed uterine arteries on transvaginal sonography performed after uterine artery embolization (UAE) and to assess the prognostic value of the "white snake" sign with regard to symptomatic outcome at 12 months. METHODS: Patients who underwent UAE from January 1, 1999, to July 31, 2000, for the treatment of symptomatic leiomyomas were included in the study. Transvaginal sonography was performed before and at 3, 6, and 12 months after UAE. Patients graded the severity of their symptoms on a scale from 1 to 5, with 1 being the least and 5 the most severe, before and at 12 months after the procedure. The Wilcoxon rank-sum test was used to determine correlations between severity of symptoms and presence of the white snake sign; a p value of less than 0.05 was considered significant. RESULTS: During the study period, UAE was performed in 19 patients with a mean age of 41 years (range, 32-48 years). UAE was technically successful in all patients. Eighteen patients (95%) reported symptomatic improvement at 12 months: 8 patients (42%) by 4 severity-scale points, 5(26%) by 3 points, and 5 (26%) by 2 points. The 1 patient who did not experience improvement had undergone a hysterectomy at 4 months after the UAE. At the 3-month follow-up, transvaginal sonography demonstrated a tortuous echogenic structure in the adnexa (the white snake sign) in all patients; the finding was still apparent in 10 patients at 6 months but in only 2 patients at 12 months. A direct correlation was found between persistence of the white snake sign and the degree of symptomatic improvement at 6 months (p=0.04) but not at 12 months (p=0.08). CONCLUSIONS: After UAE, a thrombosed uterine artery appears on transvaginal sonography as an echogenic tortuous structure in the adnexa. Persistence of this white snake sign at 6 months after UAE may suggest a more favorable symptomatic outcome. 相似文献
97.
98.
Katherine Sorsdahl Bronwyn Myers Catherine L. Ward Richard Matzopoulos Bulelwa Mtukushe Andrew Nicol 《Psychotherapy research》2013,23(4):435-444
AbstractThe purpose of this study was to examine the acceptability and initial substance use outcomes of a blended motivational interviewing (MI) and problem-solving therapy (PST) intervention, delivered by peer counsellors. Twenty people who scored at risk for substance use according to the Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) received a five session blended MI-PST intervention and were assessed at baseline and at three months. An open-ended semi-structured interview, designed to identify possible factors that may hinder or promote the acceptability of the intervention was also conducted. Fifteen participants completed the intervention and the three-month follow-up. According to ASSIST scores, participants significantly reduced their substance use (p > 0.001) at the three-month follow-up. Randomized controlled trials are needed to evaluate the effect of this intervention more rigorously. 相似文献
99.
Nadejda M. Tsankova Carolyn Bevan Vaidehi Jobanputra Yen Chen Kevin Ko Elizabeth W. Mayer Jay H. Lefkowitch Mahesh Mansukhani Lewis P. Rowland Govind Bhagat Kurenai Tanji 《Acta neuropathologica》2013,126(4):595-601
We report a rare case of peripheral T-cell lymphoma arising in a 52-year-old man with biopsy-proven aggressive polymyositis, who had cardiac involvement, progressive bulbar symptoms, and died 11 months post diagnosis due to multiorgan failure. Using a multimodality approach including immunohistochemistry, genome-wide single nucleotide polymorphism (SNP)-array analysis, and high-throughput sequencing of the complementary determining region 3 (CDR3) of T-cell receptor beta (TCRβ) genes, our study demonstrates a molecular link between polymyositis and T-cell lymphoma, and provides evidence of the rapid and possibly late occurrence of genomic instability during neoplastic transformation of an oligoclonal T-cell population. Immunohistochemical analysis revealed loss of CD5, CD7, and CD8 antigen expression in autopsy tissue samples, as well as the occurrence of aberrant CD56 expression, not seen in pre-mortem biopsies, supporting the emergence of a neoplastic T-cell population. Multiplex polymerase chain reaction and next-generation sequencing of the TCRβ CDR3 region displayed two unique T-cell clones in both the diagnostic biopsy confirming polymyositis and the autopsy muscle tissue exhibiting T-cell lymphoma, linking the two pathological processes. SNP-array analysis revealed complex genomic abnormalities at autopsy but not in the pre-mortem muscle biopsies displaying polymyositis, confirming malignant transformation of the oligoclonal T-cell infiltrate. Our findings raise the possibility that clinically aggressive polymyositis might represent a preneoplastic condition in some instances, similar to certain other autoimmune and inflammatory disorders. 相似文献
100.
B M Phillips J N Quiring J W Hurley C E Myers R E Hartnagel R L Kowalski 《The American journal of digestive diseases》1976,21(12):1029-1032
Fecal blood volume was determined daily in 11 dogs with single gastric ulcers. Beginning 11 days after production of the ulcers and dogs received, in crossover fashion, 2 placebo or ordinary 325-mg aspirin tablets orally twice daily during two 7-day treatment periods separated and followed by 5-day periods of no treatment. Mean daily fecal blood volumes of 0.52 and 3.25 ml were observed during periods of treatment with placebo and aspirin, respectively. However, in 7 previous studies in this laboratory a total of 24 normal dogs have received 7-day courses of treatment with 650 mg ordinary aspirin twice daily on 105 occasions; during these 105 treatment periods fecal blood volume averaged 2.90 ml/day. Thus, it is concluded that the effect of ordinary aspirin in dogs with gastric ulcers is essentially the same as the effect in normal dogs, and that there is no tendency for dogs with gastric ulcers to bleed massively in response to aspirin. 相似文献