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61.
Human Aldehyde Dehydrogenase: Kinetic Identification of the Isozyme for Which Biogenic Aldehydes and Acetaldehyde Compete 总被引:1,自引:0,他引:1
Alexander D. MacKerell Jr PhD Erich E. Blatter BS Regina Pietruszko PhD 《Alcoholism, clinical and experimental research》1986,10(3):266-270
Michaelis constants and maximal velocities for phenylacetaldehyde (a metabolite of phenylethylamine), 3,4-dihydroxyphenylacetaldehyde (a metabolite of dopamine), 5-hydroxyindole acetaldehyde (a metabolite of serotonin), and 3,4-dihydroxyphenylglycolaldehyde (a metabolite of epinephrine and norepinephrine) have been determined for both cytoplasmic (E1) and mitochondrial (E2) isozymes of human liver aldehyde dehydrogenase (EC 1.2.1.3). Kinetic constants with biogenic aldehydes have never been previously determined for individual homogeneous isozymes of aldehyde dehydrogenase from any species. Mathematical treatment of these constants suggests that competition with acetaldehyde during alcohol metabolism would severely inhibit dehydrogenation of biogenic aldehydes with the mitochondrial and not the cytoplasmic isozyme of human liver aldehyde dehydrogenase. 相似文献
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Steven R. Alexander Gerald S. Arbus Khalid M. H. Butt Susan Conley Richard N. Fine Ira Greifer Alan B. Gruskin William E. Harmon Paul T. McEnery Thomas E. Nevins Nadia Nogueira Oscar Salvatierra Jr Amir Tejani 《Pediatric nephrology (Berlin, Germany)》1990,4(5):542-553
This report of the North American Pediatric Transplant Cooperative Study summarizes data contributed by 57 participating centers on 754 children with 761 transplants from 1 January 1989 to 16 February 1989. Data collection was initiated in October 1987 and follow-up of all patients is ongoing. Transplant frequency increased with age; 24% of the patients were less than 5 years, with 7% being under 2 years. Common frequent diagnoses were: aplastic/dysplastic kidneys (18%), obstructive uropathy (16%), and focal segmental glomerulosclerosis (12%). Preemptive transplant, i.e., transplantation without prior maintenance dialysis, was performed in 21% of the patients. Dialytic modalities pretransplant were peritoneal dialysis in 42% and hemodialysis in 25%. Bilateral nephrectomy was reported in 29%. Live-donor sources accounted for 42% of the transplants. Among cadaveric donors, 41% of the donors were under 11 years old. During the first post-transplant month, maintenance therapy was used similarly for live-donor and cadaver source transplants, with prednisone, cyclosporine, and azathioprine used in 93%, 83%, and 81%, respectively. Triple therapy with prednisone, cyclosporine, and azathioprine was used in 78%, 75%, and 75% of functioning cadaver source transplants at 6 months, 12 months, and 18 months as opposed to 60%, 63%, and 54% for live-donor procedures, with single-drug therapy being uncommon. Rehospitalization during months 1–5 occurred in 62% of the patients, with treatment of rejection and infection being the main causes. Additionally, 9% were hospitalized for hypertension. During months 6–12 and 12–17, 30% and 28% of the patients with functioning grafts were rehospitalized. Times to first rejection differed significantly for cadaver and live-donor transplants. The median time to the first rejection was 36 days for cadaver transplants and 156 days for live-donor transplants. Overall, 57% of treated rejections were completely reversible although the complete reversal rate decreased to 37% for four or more rejections. One hundred and fifty-two graft failures had occurred at the time of writing, with a 1-year graft survival estimate of 0.88 for live-donor and 0.71 for cadaver source transplants. In addition to donor source, recipient age is a significant prognostic factor for graft survival. Among cadaver donors, decreasing donor age is associated with a decreasing probability of graft survival. Thirty-five deaths have occurred; 16 attributed to infection and 19 to other causes. The current 1-year survival estimate is 0.94. There have been 9 malignancies.A list of all participating centers and the names of the investigators is printed on pages 552–553 相似文献
64.
Alexander Kulik Marc Ruel Michael E Bourke Lynn Sawyer John Penning Howard J Nathan Thierry G Mesana Pierre Bédard 《European journal of cardio-thoracic surgery》2004,26(4):694-700
OBJECTIVE: Non-steroidal anti-inflammatory drugs (NSAIDs) are routinely used after coronary artery bypass surgery (CABG), yet their effects have seldom been evaluated in randomized controlled settings. The aim of this study was to examine the efficacy and safety of a commonly used NSAID, naproxen. We hypothesized that naproxen would reduce postoperative pain following CABG without increasing complications. METHODS: Patients (N=98) undergoing primary CABG were randomized to receive naproxen (500 mg q12hX5 doses via suppository started 1h after operation, followed by oral 250 mg q8hX6 doses) or placebo. Standard analgesic and anti-emetic regimens were available to both patient groups. Interventions were double-blinded. Primary end-points were postoperative pain measured before and after chest physiotherapy by visual analog scale and pulmonary slow vital capacity (SVC). RESULTS: Baseline characteristics were equivalent between the two groups. Over the first 4 postoperative days, naproxen decreased pain by 47+/-17% on average before chest physiotherapy (P=0.034), and 44+/-13% after chest physiotherapy (P=0.0092). Patients who received naproxen also had better preservation of SVC over the first 4 postoperative days (mean loss of SVC from baseline: 2.1+/-0.1 vs. 2.5+/-0.1l, naproxen vs. placebo, P=0.0032). This was concomitant with a lower white blood cell count observed in naproxen patients (9.2+/-0.3 vs. 12.7+/-1.5x10(9)/l, naproxen vs. placebo, P=0.03). Patients who received naproxen had more chest tube drainage after 4h postoperatively, but there was no difference in the incidence or amount of transfusions. There was no difference in medication use, length of stay, or in the incidence of atrial fibrillation, azotemia, and other complications. CONCLUSIONS: Naproxen is an effective and low-cost adjunct for optimization of pain control and lung recovery after CABG. Its use may result in increased chest tube drainage, but no apparent increase in other complications. 相似文献
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Sofya N Pchelina Andrei F Yakimovskii Olga N Ivanova Anton K Emelianov Andrei H Zakharchuk Alexander L Schwarzman 《Movement disorders》2006,21(12):2234-2236
Among mutations associated with autosomal dominant and sporadic Parkinson's disease (PD) the G2019S substitution in the leucine-rich repeat kinase 2 (LRRK2) gene is the most frequently identified. To estimate its frequency in Russia, we analyzed 208 patients with PD from the Northwestern region of Russia. Of these, 51 patients were probands from families with PD compatible with autosomal dominant inheritance. The control group represented 161 subjects without neurological disorders settled in the same region. The frequency of the G2019S mutation was greater in familial PD (2 [3.9%] of 51) than in sporadic PD (1 [0.6%] of 157). In addition, this mutation was found in the proband's father, who also had PD, in 1 PD family, and in 1 carrier without signs of PD at age 40 in another PD family. All carriers were heterozygous for the G2019S mutation and reported the Ashkenazi Jewish origin. The mutation was not found in the control group. 相似文献
67.
Thomas Verse Alexander Baisch Joachim T Maurer Boris A Stuck Karl H?rmann 《Otolaryngology--head and neck surgery》2006,134(4):571-577
OBJECTIVE: To determine the efficacy of a new multilevel surgical protocol for obstructive sleep apnea (OSA). STUDY DESIGN AND SETTING: Sixty patients with moderate to severe OSA because of multilevel pharyngeal obstruction were enrolled into this prospective, controlled clinical trial after clinical examination, endoscopy, and polysomnography. Surgery included uvulaflap, tonsillectomy, hyoid suspension, and radiofrequency treatment of the tongue base (group A). A second group did not receive hyoid suspension (group B). In both groups, nasal surgery was performed if necessary. Polysomnography and Epworth Sleepines Scale (ESS) were recorded at baseline and 2 to 15 months after surgery. RESULTS: In group A, the mean apnea-hypopnea index (AHI) decreased significantly after surgery (38.9 +/- 20.0 vs 20.7 +/- 20.6, P < 0.0001), whereas in group B the AHI did not. All secondary variables (minimal oxygen saturation, mean oxygen saturation, arousal index), and the ESS significantly improved in group A with only changes in arousal index and ESS reaching levels of significance in group B. CONCLUSION: The presented protocol including the hyoid suspension proved to be effective in the treatment of OSA, whereas surgery without hyoid suspension was less successful. EBM rating: B-2b. 相似文献
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69.
Eugene Rossitch Jr. Eben Alexander III Steven J. Schiff Dennis E. Bullard 《Clinical neurology and neurosurgery》1988,90(4):365-368
A case of a brain stem abscess that was successfully treated using CT guided stereotaxy together with antibiotic therapy is presented. The literature is reviewed and the role of stereotaxy in the treatment of brain stem abscess is discussed. 相似文献
70.