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排序方式: 共有772条查询结果,搜索用时 15 毫秒
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H. Kaufmann E. Oribe M. D. Yahr 《Journal of neural transmission (Vienna, Austria : 1996)》1991,3(2):143-148
Summary Treatment with L-threo-3,4-dihydroxyphenylserine (L-threo-dops), a synthetic precursor of norepinephrine, significantly increased upright blood pressure in patients with multiple system atrophy but had no effect on the upright blood pressure of patients with pure autonomic failure. These results suggest that the site of action of L-threo-dops is central and that its pressor effect requires intact peripheral sympathetic neurons. 相似文献
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Jesús M. Cesar Ana Vecino Mikel Perez-Vaquero Jos L. Navarro 《European journal of haematology》1993,50(4):234-236
Abstract: Red cell phospholipids (PLs) were assessed in 11 patients with essential thrombocythemia and 5 patients with polycythemia vera. Platelet and plasma PLs were also determined in 10 of these patients, and the results were compared with studies performed in 16 healthy volunteers. The amount of platelet PLs in patients was similar to controls (556 ± 90 nmol/109cells, versus 481 ± 91 nmol/109cells), as was the percentage of the main specimens of these compounds, including phosphatidylserine (11.1 ± 0.8%), which is relevant for platelet procoagulant activity. We did not find differences between red cell PLs of patients (300 ± 60 nmol/109cells), versus controls (289 ± 71 nmol/109cells), and the sphingomyelin/phosphatidylcholine ratio in these cells was the same in both groups (0.75 ± 0.1). Finally, we did not detect any alteration in the amount of plasma PLs specimens. 相似文献
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Scott L. Nyberg Arthur J. Matas Walter K. Kremers Jeffrey D. Thostenson Timothy S. Larson Mikel Prieto Michael B. Ishitani Sylvester Sterioff Mark D. Stegall 《American journal of transplantation》2003,3(6):715-721
We previously proposed a quantitative approach to assess donor organs for cadaver renal transplantation. To improve on our original scoring system, we studied 34 324 patients who received cadaver renal transplants from adult donors between 1994 and 1999 and were reported to the UNOS Scientific Renal Transplant Registry. A scoring system was developed from five donor variables (age, 0-25 points; history of hypertension, 0-4; creatinine clearance before procurement, 0-4; cause of death, 0-3; HLA mismatch, 0-3) that showed a significant correlation with renal function and long-term graft survival. Cadaver kidneys were stratified by cumulative donor score: grade A, 0-9 points; grade B, 10-19; grade C, 20-29; and grade D, 30-39. The influence of donor score on renal function and graft survival was most severe above 20 points, designated 'marginal' kidneys. In summary, a donor scoring system developed from a large population database was useful in predicting outcome after cadaver renal transplantation. The improved system provides a quantitative approach to evaluation of marginal kidneys and may improve allocation of these organs in cadaver renal transplantation. 相似文献
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Siva Narayanan John Van Vleet Billy Strunk Robert N Ross Mikel Gray 《Journal of wound, ostomy, and continence nursing》2005,32(3):163-170
This study compared clinical outcomes and nursing labor costs associated with (a) balsam Peru, hydrogenated castor oil, and trypsin (BCT) ointment; (b) BCT + Other; and (c) Other treatments in 2014 wound episodes occurring in 861 patients (mean 2.34 wounds/patient). Treatment with BCT ointment or BCT + Other was associated with a higher healing rate (P < .05). No Stage 1 or 2 ulcer treated with BCT ointment progressed, compared with 13.8% treated with BCT + Other and 13.4% treated with Other. The reported mean duration of treatment and time to heal were shorter for ulcers treated with BCT ointment, but differences did not reach significance, possibly because of the variability in reported treatment times. Mean daily nursing labor costs were lower for treatment with BCT than Other ($50.8 vs $61.7, P < .05). These data suggest that treatment of Stage 1 or 2 ulcers with BCT may be associated with shorter treatment time and time to heal and a potential reduction in treatment-related nursing labor costs. 相似文献
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Mònica Gratacòs Juan R González Josep M Mercader Rafael de Cid Mikel Urretavizcaya Xavier Estivill 《Neuropsychopharmacology》2007,61(7):911-922
BACKGROUND: There is an increasing recognition that the pathophysiology of mental disorders could be the result of deregulation of synaptic plasticity with alterations of neurotrophins. The valine (Val)66-to-methionine (Met) variant, located in the pro brain-derived neurotrophic factor (BDNF) sequence, has been extensively studied through linkage and association approaches in several psychiatric disorders. METHODS: We performed a meta-analysis restricted to individual case-control studies in different categories of mental disorders and BDNF Val66Met polymorphism. We included data from 39 case-control studies encompassing psychiatric phenotypes: eating disorders, substance-related disorders, mood disorders, and schizophrenia, among others. RESULTS: The association of Val66Met was confined to three diagnoses: substance-related disorders, eating disorders, and schizophrenia. The Val/Met and the Met/Met genotypes increase the risk for eating disorders up to 33%, while these same genotypes confer a 21% protective effect in substance-related disorders. The homozygous carriers Met/Met showed a 19% increased risk of schizophrenia with respect to the heterozygous state. CONCLUSIONS: The study confirms the association of Val66Met to substance-related disorders, eating disorders, and schizophrenia. It remains to be determined if other variants in tight linkage disequilibrium with Val66Met could configure an extended functional haplotype that would explain observed discrepancies in risk estimations across studies. 相似文献
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Potentiation of allergic bronchoconstriction by repeated exposure to formaldehyde in guinea-pigs in vivo 总被引:2,自引:0,他引:2
T. Kita M. Fujimura S. Myou Y. Ishiura M. Abo N. Katayama M. Nishitsuji Y. Yoshimi S. Nomura Y. Oribe S. Nakao 《Clinical and experimental allergy》2003,33(12):1747-1753
BACKGROUND: Indoor formaldehyde (FA) might worsen allergies and be an underlying factor for the increasing incidence and severity of asthma; the exact mechanism, however, remains unclear. OBJECTIVE: The present study examined the effects of repeated exposure to FA on methacholine- and antigen-induced bronchoconstriction in guinea-pigs in vivo. METHODS: First, non-sensitized guinea-pigs were transnasally treated with 0.1 or 1.0% FA or saline three times a week for 6 weeks, and increasing concentrations of methacholine (50, 100, and 200 microg/mL) were inhaled at 5-min intervals. Second, guinea-pigs pre-treated with transnasal administration of FA or saline using the same protocol were passively sensitized with anti-ovalbumin (OA) serum 7 days before antigen challenge. Third, guinea-pigs were actively sensitized with OA and pre-treated with transnasal administration of FA or saline using the same protocol. The lateral pressure of the tracheal tube (Pao) was measured under anesthesia and artificial ventilation. RESULTS: The antigen-induced increase in Pao in actively sensitized guinea-pigs was significantly potentiated by FA exposure in a dose-dependent manner. The dose-response curve of the methacholine-induced increase in Pao in non-sensitized guinea-pigs or of the antigen-induced increase in Pao in passively sensitized guinea-pigs was not altered by FA exposure. Transnasal administration of FA significantly increased the serum anti-OA homocytotropic antibody titre (IgG) as measured by the passive cutaneous anaphylaxis reaction in actively sensitized guinea-pigs. CONCLUSION: The results suggest that repeated exposure to FA worsens allergic bronchoconstriction through enhancing antigen sensitization. 相似文献