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91.
Rebecca Suckling Mohamed Morsy Eric S Chemla 《Nephrology, dialysis, transplantation》2007,22(3):970-971
Sir, The expansion of haemodialysis includes older patients withcomorbidities, poor quality vessels, unsuitable for transplantationor peritoneal dialysis. Vascular access complications accountfor 20% of hospital admissions [1]. With exhausted sites inupper extremities, unusual sites for arteriovenous grafts formationare used [2]. The 相似文献
92.
93.
Rebecca A. Adams David C. Dollahite Kathleen R. Gilbert Robert E. Keim 《Family relations》2001,50(1):41-48
This article describes the development of the Ethical Principles and Guidelines for Family Scientists that the National Council on Family Relations Board of Directors unanimously approved. Furthermore, it discusses the importance of ethics education for family professionals and provides suggestions for educators. Finally, the ethical principles and guidelines are delineated. We argue that the development of a scholarship on ethics education is important for current and future family scientists. 相似文献
94.
Schrader Jürgen Gerlach Eckehart 《Pflügers Archiv : European journal of physiology》1976,367(2):129-135
Summary After prelabeling the adenine nucleotides (ATP, ADP, AMP) of isolated perfused guinea pig hearts with either14C-adenine or14C-adenosine for 35 min, labeled adenosine, inosine, hypoxanthine and cyclic 35-AMP (cAMP) were continuously released into the cardiac perfusate. Determination of the specific activities (SA) of the adenine nucleotides, cAMP, and their breakdown products (adenosine, inosine, hypoxanthine) in tissue and perfusate revealed: Under steady state conditions the SA of adenosine and cAMP in the perfusate were of the same order of magnitude and proved to be many times higher than the SA of the respective precursor adenine nucleotides. This difference was observed regardless whether adenine or adenosine was used as prelabeling substance. The SA of inosine and hypoxanthine in the perfusate were constantly lower than the SA of adenosine. Cardiac ischemia of 6 min, which resulted in a markedly increased formation of adenosine, led to a pronounced decrease in the SA of adenosine released from the heart.Our findings provide evidence that at least two different adenine nucleotide compartments of the heart serve as precursors for the formation of adenosine and cAMP, one characterized by a high, the other by a lower SA. Under normoxic conditions adenosine and cAMP released into the cardiac perfusate are derived mainly from a nucleotide fraction of high SA, which appears to be rather small. During ischemia a second compartment of much lower SA in addition contributes to the formation of adenosine.A preliminary report of part of this work appeared in Biochemistry and Pharmacology of Myocardial Hypertrophy, Hypoxia and Infarction Vol. 7 of Recent advances in studies on cardiac structure and metabolism. (P. Harris, R. J. Bing, A. Fleckenstein, eds.), pp. 171–175. München: Urban & Schwarzenberg 1976A preliminary report of part of this work appeared in Biochemistry and Pharmacology of Myocardial Hypertrophy, Hypoxia and Infarction Vol. 7 of Recent advances in studies on cardiac structure and metabolism. (P. Harris, R. J. Bing, A. Fleckenstein, eds.), pp. 171–175. München: Urban & Schwarzenberg 1976 相似文献
95.
Cody JD Semrud-Clikeman M Hardies LJ Lancaster J Ghidoni PD Schaub RL Thompson NM Wells L Cornell JE Love TM Fox PT Leach RJ Kaye CI Hale DE 《American journal of medical genetics. Part A》2005,137(1):9-15
Most individuals with constitutional deletions of chromosome 18q have developmental delays, dysmyelination of the brain, and growth failure due to growth hormone deficiency. We monitored the effects of growth hormone treatment by evaluating 23 individuals for changes in growth, nonverbal intelligence quotient (nIQ), and quantitative brain MRI changes. Over an average of 37 months, the treated group of 13 children had an average nIQ increase of 17 points, an increase in height standard deviation score of 1.7, and significant change in T1 relaxation times in the caudate and frontal white matter. Cognitive changes of this magnitude are clinically significant and are anticipated to have an effect on the long-term outcomes for the treated individuals. 相似文献
96.
The purpose of this study was to determine whether serum lactate dehydrogenase (LDH) level could be used as an adjunct clinical marker to differentiate between histoplasmosis and Pneumocystis carinii pneumonia (PCP). In a retrospective, case-controlled study, 30 patients with a diagnosis of histoplasmosis (all but 1 with disseminated disease) were compared with 120 patients with PCP (33 patients with definitive PCP, 87 with presumed PCP). Groups were matched for CD4+ lymphocyte counts, sex, and year of diagnosis. The mean LDH level for patients with histoplasmosis was 1068 +/- 197 IU/L; for PCP, it was 375 +/- 23. An LDH level of more than 450 IU/L was 9.33 times more likely to be associated with a diagnosis of histoplasmosis than with PCP (odds ratio [OR], 9.33; 95% confidence interval [CI], 3.50-25.47; P < .01), and an LDH level of more than 600 IU/L was 9.41 times more likely to be so (OR, 9.41; 95% CI, 3.43-26.31; P < .01). An LDH level of 450 IU/L or greater had a sensitivity and specificity of 70% and 80%, respectively; a value of 600 IU/L or greater had sensitivity and specificity of 50% and 89%. Thus, serum LDH levels of 600 IU/L or greater are suggestive of histoplasmosis rather than PCP in appropriate clinical settings. Serum LDH may serve as an adjunct laboratory marker in the diagnosis of histoplasmosis. Elevated levels may prompt the physician to look for a diagnosis other than PCP early in the course of the illness. 相似文献
97.
Ulrich Gerlach 《Journal of molecular medicine (Berlin, Germany)》1963,41(17):873-876
Zusammenfassung Aus Rattenherzen wurde ein sulfataktivierendes Enzymsystem extrahiert.Hiermit konnte bei Verwendung von S35O
4
--
markiertes aktives Sulfat (Lipmann) synthetisiert werden.Es zeigte sich, daß die Aktivität des Enzymsystems vom Lebensalter der Versuchstiere abhängig ist. Die biologische Bedeutung des Befundes wird besprochen.Die Deutsche Forschungsgemeinschaft unterstützte in dankenswerter Weise die Arbeit. 相似文献
98.
Guy RJ Breschkin AM Keenan CM Catton MG Enriquez AM Hellard ME 《Journal of acquired immune deficiency syndromes (1999)》2005,38(4):495-499
Between 1999 and 2000, new diagnoses of HIV in Victoria (Australia) rose by 41%, from 140 to 197. In this time period, sera from new HIV diagnoses were tested using the Organon Teknika "detuned" enzyme immunoassay (EIA). We compared the results of the detuned EIA with incident infections defined by surveillance (on the basis of a previous negative or indeterminate HIV test and/or a seroconversion illness within the 12 months preceding HIV diagnosis). Of 317 specimens, 97 (31%) incident infections and 114 (36%) recent infections were detected using surveillance and detuned EIA, respectively. The detuned assay misclassified 11 cases with AIDS and 2 cases with CD4 counts < or = 200 micro3 (probable long-standing infections) as recent infections and was unable to identify 31 (32%) of 97 cases previously classified as incident cases by surveillance. The assay detected an extra 35 recent infections that were previously classified as nonincident by surveillance. By combining the detuned assay and surveillance, 132 (42%) incident infections were identified from 317 specimens, 36% more than surveillance alone. We recommend that a detuned assay or similar test become part of the routine strategy to identify incident infections in Victoria. Incident infections provide important information for targeting prevention strategies and the opportunity to interrupt ongoing viral transmission. 相似文献
99.
Chaiken J Finney W Knudson PE Weinstock RS Khan M Bussjager RJ Hagrman D Hagrman P Zhao Y Peterson CM Peterson K 《Journal of biomedical optics》2005,10(3):031111
Tissue modulated Raman spectroscopy was used noninvasively to measure blood glucose concentration in people with type I and type II diabetes with HemoCue fingerstick measurements being used as reference. Including all of the 49 measurements, a Clarke error grid analysis of the noninvasive measurements showed that 72% were A range, i.e., clinically accurate, 20% were B range, i.e., clinically benign, with the remaining 8% of measurements being essentially erroneous, i.e., C, D, or E range. Rejection of 11 outliers gave a correlation coefficient of 0.80, a standard deviation of 22 mg/dL with p<0.0001 for N=38 and places all but one of the measurements in the A and B ranges. The distribution of deviations of the noninvasive glucose measurements from the fingerstick glucose measurements is consistent with the suggestion that there are at least two systematic components in addition to the random noise associated with shot noise, charge coupled device spiking, and human factors. One component is consistent with the known variation of fingerstick glucose concentration measurements from laboratory reference measurements made using plasma or whole blood. A weak but significant correlation between the deviations of noninvasive measurements from fingerstick glucose measurements and the test subject's hemoglobin concentration was also observed. 相似文献
100.
Combined reflectance and fluorescence spectroscopy for in vivo detection of cervical pre-cancer 总被引:1,自引:0,他引:1
Chang SK Mirabal YN Atkinson EN Cox D Malpica A Follen M Richards-Kortum R 《Journal of biomedical optics》2005,10(2):024031
Optical technologies, such as reflectance and fluorescence spectroscopy, have shown the potential to provide improved point-of-care detection methods for cervical neoplasia that are sensitive, specific, and cost-effective. Our specific goals are to analyze the diagnostic potential of reflectance and fluorescence spectra, alone and in combination, to discriminate normal and precancerous cervical tissue in vivo and to identify which classification features contain significant diagnostic information. Reflectance spectra are measured at four source-detector separations and fluorescence emission spectra are measured at 16 excitation wavelengths, from 324 sites in 161 patients. These 20 spectral features are permuted in all possible combinations of one, two, and three; and classification algorithms are developed to evaluate the diagnostic performance of each combination. Algorithms based on fluorescence spectra alone yield better diagnostic performance than those based on reflectance spectra alone. The combination of fluorescence and reflectance do not significantly improve diagnostic performance compared to fluorescence alone, except in the case of discriminating high-grade precancers from columnar normal tissue. In general, fluorescence emission spectra at 330- to 360-nm and 460- to 470-nm excitation provide the best diagnostic performance for separating all pairs of tissue categories. 相似文献