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51.
Methylmalonic aciduria is a rare metabolic disorder of amino acid metabolism that is characterized by accumulation of large amounts of methylmalonic acid in the blood and urine. To our knowledge this is the first case report of a patient with methylmalonic aciduria who carried a pregnancy to term; the outcome was favorable despite high levels of methylmalonic acid in the serum and urine. 相似文献
52.
AS Stein MR O'Donnell A Chai GM Schmidt A Nademanee PM Parker EP Smith DS Snyder A Molina DE Stepan R Spielberger G Somlo KA Margolin N Vora J Lipsett J Lee J Niland SJ Forman 《Canadian Metallurgical Quarterly》1996,14(8):2206-2216
PURPOSE: To evaluate in a prospective study the efficacy of autologous bone marrow transplantation (BMT) in adult patients with acute myelogenous leukemia (AML) in first remission, using a single course of high-dose Cytarabine (HD Ara-C) consolidation therapy as in vivo purging. PATIENTS AND METHODS: Sixty consecutive adult patients with AML in first complete remission (CR) were treated with HD Ara-C consolidation therapy as a method of in vivo purging before marrow collection. High-dose therapy consisted of fractionated total-body irradiation (FTBI) 12 Gy, intravenous etoposide 60 mg/kg, and cyclophosphamide 75 mg/kg, followed by reinfusion of cryopreserved marrow. RESULTS: Sixty patients underwent consolidation treatment with HD Ara-C with the intent to treat with autologous BMT. Sixteen patients were unable to proceed to autologous BMT (10 patients relapsed, one died of sepsis, one developed cerebellar toxicity, two had inadequate blood counts, and two refused). Forty-four patients underwent autologous BMT and have a median follow-up time of 37 months (range, 14.7 to 68.7) for patients who are alive with no relapse. The cumulative probability of disease-free survival (DFS) at 24 months in the intent-to-treat group is 49% (95% confidence interval [CI], 37% to 62%) and in those who actually underwent autologous BMT is 61% (95% CI, 46% to 74%). The probability of relapse was 44% (95% CI, 31% to 58%) and 33% (95% CI, 20% to 49%) for the intent-to-treat and autologous BMT patients, respectively. CONCLUSION: This approach offers a relatively high DFS rate to adult patients with AML in first CR. The results of this study are similar to those achieved with allogeneic BMT. 相似文献
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54.
Christopher L Brown Gillian Bushell Michael W Whitehouse DS Agrawal SG Tupe KM Paknikar Edward RT Tiekink 《Gold bulletin》2007,40(3):245-250
Nanosized gold particles (27 +/− 3 nm) have been proven to be effective in ameliorating the symptoms of mycobacterial-, collagen-
and pristane-induced arthritis in rat models. This contrasts with the drug sodium aurothiomalate that was only effective against
mycobacterial-induced arthritis but not to the same extent as Au0. Gold in the traditional Indian Ayurvedic medicine,Swarna bhasma (gold ash), has been characterized as globular particles of gold with an average size of 56–57 nm. 相似文献
55.
Investigations were carried out in a long term field experiment from 1976 to 1982, on a loamy sand soil to find out the fertilizer requirements of groundnut and wheat grown in fixed rotation. Application of 26 kgP/ha to wheat alone was found to be sufficient for both wheat and succeeding groundnut. Application of phosphorus to both wheat and groundnut did not result in extra beneficial effect over P application to wheat alone. However, application of 26 kg P/ha to groundnut alone was not sufficient for succeeding wheat. There was no response from K application (25 kg K/ha) in either of these two crops. Increasing the dose of N from 50–150 kg/ha to wheat significantly increased the grain yield of wheat but the pod yield of succeeding groundnut were markedly lowered. Response of wheat to 150 kg N/ha was more marked when P was also applied to wheat and response was less when P was applied to preceding groundnut alone. Zinc application at 6.25 kg/ha to wheat alone resulted in significant increase in grain yield of wheat and pod yield of succeeding groundnut. 相似文献
56.
Praying mantids are models for a wide variety of behavioral, physiological, and ecological studies, and sex pheromones have been assumed to be important components of their biology. However, no mantid pheromone has ever been identified. We collected volatiles emitted by females of the mantid, Sphodromantis lineola, via solid phase microextraction (SPME). Mass spectral analysis revealed the collected volatiles to be a mixture of pentadecanal and tetradecanal. We prepared a synthetic mixture of these compounds, and found that males were both attracted to this mixture and stimulated to exhibit typical precopulatory behavior. We then examined male antennae with scanning electron microscopy, and confirmed the presence of porous antennal sensilla typical of insect pheromone receptors, i.e., that male mantids are equipped with the appropriate morphological apparatus to receive volatile chemical signals. Pheromones, in conjunction with visual and tactile cues, are thus an important feature of the reproductive biology of this, and undoubtedly other species of mantids. In addition to adding a crucial aspect of behavioral biology to our knowledge of this group, identification and synthesis of mantid pheromones may be a first step in attracting and aggregating these generalist predators for use in pest control. 相似文献
57.
PERIODIC CORRELATION IN STRATOSPHERIC OZONE DATA 总被引:1,自引:0,他引:1
Abstract. A 50-year time series of monthly stratospheric ozone readings from Arosa, Switzerland, is analyzed. The time series exhibits the properties of a periodically correlated (PC) random sequence with annual periodicities. Spectral properties of PC random sequences are reviewed and a test to detect periodic correlation is presented. An autoregressive moving-average (ARMA) model with periodically varying coefficients (PARMA) is fitted to the data in two stages. First, a periodic autoregressive model is fitted to the data. This fit yields residuals that are stationary but non-white. Next, a stationary ARMA model is fitted to the residuals and the two models are combined to produce a larger model for the data. The combined model is shown to be a PARMA model and yields residuals that have the correlation properties of white noise. 相似文献
58.
59.
DS Berman R Hachamovitch H Kiat I Cohen JA Cabico FP Wang JD Friedman G Germano K Van Train GA Diamond 《Canadian Metallurgical Quarterly》1995,26(3):639-647
OBJECTIVES: This study assessed the incremental prognostic implications of normal and equivocal exercise technetium-99m (Tc-99m) sestamibi single-photon emission computed tomography (SPECT) and sought to determine its incremental prognostic value, impact on patient management and cost implications. BACKGROUND: The prognostic implications of Tc-99m sestamibi SPECT are not well defined, and risk stratification using this test has not been explored. METHODS: We studied 1,702 patients referred for exercise Tc-99m sestamibi SPECT who were followed up for a mean (+/- SD) of 20 +/- 5 months. Patients with previous percutaneous transluminal coronary angioplasty or coronary artery bypass surgery were excluded. The SPECT studies were assessed using semiquantitative visual analysis. Cardiac death and myocardial infarction were considered "hard" events, and coronary angioplasty and bypass surgery > 60 days after testing were considered "soft" events. RESULTS: Of the 1,702 patients studied, 1,131 had normal or equivocal scan results. A total of 10 events occurred in this group (1 cardiac death and 1 myocardial infarction [0.2% hard events]; 4 coronary angioplasty and 4 bypass surgery procedures [0.7% soft events]). The rates of hard events and referral to catheterization after SPECT were similarly low in patients with a low (< 0.15), intermediate (0.15 to 0.85) and high (> 0.85) post-exercise treadmill test (ETT) likelihood of coronary artery disease. With respect to scan type, patients with normal, probably normal or equivocal scan results had similarly low hard event rates. In the 571 patients with abnormal scan results, there were 43 hard events (7.5%) and 42 soft events (7.4%) (p < 0.001 vs. 1,131 patients with normal scan results for both). When the complete spectrum of scan responses was considered, SPECT provided incremental prognostic value in all patient subgroups analyzed. However, the nuclear scan was cost-effective only in patients with interpretable exercise ECG responses and an intermediate to high post-ETT likelihood of coronary artery disease and in those with uninterpretable exercise ECG responses and an intermediate to high pre-ETT likelihood of coronary artery disease. CONCLUSIONS: Normal or equivocal exercise Tc-99m sestamibi study results are associated with a benign prognosis, even in patients with a high likelihood of coronary artery disease. Although incremental prognostic value is added by nuclear testing in all patient subgroups, a testing strategy incorporating nuclear testing proved to be cost-effective only in the groups with an intermediate to high likelihood of coronary artery disease before scanning. 相似文献
60.
Time-resolved absorption difference spectra of membrane suspensions of bovine rhodopsin at pH 5, 6, 7, 8, 9, and 10 were collected in the time range from 1 micro s to 200 ms after laser photolysis with 7-ns pulses of 477-nm light. The data were analyzed using singular value decomposition (SVD) and global exponential fitting. At pH 7 the data agree well with previously obtained data (Thorgeirsson et al. (1993) Biochemistry 32, 13861-13872) with fits improved at all pH's by inclusion of a small component due to an absorbance change caused by rotational diffusion which is detectable even at magic angle polarization. A "square scheme" suggested to best explain the previous data, which involves two branches following decay of the lumi intermediate with pathways (1) lumi --> MI480 right harpoon over left harpoon MII and (2) lumi right harpoon over left harpoon MI380 --> MII, could be confirmed throughout the entire pH range. However, to account for the increased rate of the MII --> MI480 reaction in path 1 for rising pH values, we propose that the MII in the square scheme consists of deprotonated MII and protonated MIIH+ forms in rapid equilibrium with each other, resulting in an extended square scheme and increasing the number of 380-nm products from two to three. In addition to the kinetic processes described by the extended square scheme, above pH 8 fast ( approximately 10 micro s) and slow ( approximately 50 ms) components were found. The fast component was assigned to the decay of a blue-shifted lumi intermediate, and the slow component, resolvable only at pH 10, was assigned to formation of a 450 nm absorbing photoproduct. 相似文献