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101.
102.
László Prónai Hiroe Nakazawa Kohji Ichimori Yoshinori Saigusa Tomoichi Ohkubo Kazuko Hiramatsu Shigeru Arimori János Fehér 《Inflammation》1992,16(5):437-450
This study was performed to examine the pattern of Superoxide (O
2
–
·) generation from leukocytes using the O
2
–
· specific chemiluminescence (CL) method.Cypridina luciferin analog, 2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo[1,2-alpha]pyrazin-3-one (MCLA) was used as a CL probe. The appropriate conditions of the MCLA method was first determined for the evaluation of the time course of O
2
–
· generation by leukocytes. The time course of O
2
–
· generation obtained by the MCLA-CL system was compared with that by the luminol-dependent CL, electron spin resonance (ESR)/spin trapping, and cytochromec systems. Following stimulation by three different stimulants (PMA, OZ, FMLP), leukocytes continuously generated O
2
–
· for up to 5 h in the MCLA-CL system, irrespective of the kind of stimulation. The curves obtained by generation ceased more rapidly in the luminol-CL, ESR/spin trapping, and cytochromec systems. A 50% activity of the initial value was observed at 70 min in the MCLA-CL system, but 30, 10 and 35 min in the other systems, respectively. The CL or O
2
–
· generation value decreased to less than 1% (possible termination) at 300, 90, 120 and 180 min, respectively. With the exception of ESR studies with OZ, the cell viability was not significantly affected in any of the trials. These results indicate that leukocytes can generate O
2
–
· much longer than previously estimated and that the MCLA-CL-system is the most suitable system for the measurement of the O
2
–
· generation by leukocytes. 相似文献
103.
The advantages and limitations of the slowing down of epithermal neutrons and the thermal neutron reflection methods were compared for bulk hydrogen analysis. In both cases, the same sample dimensions were used, i.e. 10cm diameter and 8cm height. It was found that the sensitivity of the slowing down method is higher by a factor of approximately 20 in average and the matrix effect can be neglected as compared to the neutron reflection technique. The simultaneous application of the two methods renders the determination of the H content and the C/H atomic ratio possible. The effect of spatial distribution of hydrogen in the matrix to be investigated on the number of reflected neutrons was also studied. 相似文献
104.
Neurodevelopmental treatment (NDT) is the most used rehabilitation approach in the treatment of patients with stroke in the Western world today, despite the lack of evidence for its efficacy. The aim of this study was to conduct an intervention check and measure the nurses' competence, in positioning stroke patients according to the NDT approach. The sample consisted of 144 nurses in six neurological wards who were observed while positioning stroke patients according to the NDT approach. The nurses' combined mean competence scores within the wards was 195 (70%) of 280 (100%) possible, and for each ward the mean score varied between 181 (65%) and 206 (74%). This study indicates that nurses working in hospitals where the NDT approach has been implemented have the knowledge and skills to provide NDT nursing. 相似文献
105.
Aida Brand?o Sónia Magalh?es Adelino Correia 《Revista portuguesa de cardiologia》2004,23(7-8):993-999
Congenitally corrected transposition of the great arteries, L-TGA, is a rare abnormality accounting for less than 0.5% of clinically apparent congenital heart disease. Age at time of diagnosis and survival rate are variable and depend mostly on associated anomalies. The authors present a clinical case of a twenty-four-year-old woman in whom, in a routine echocardiogram, congenitally corrected transposition of the great arteries and aortic coarctation were diagnosed, an unusual association. They describe the results of complementary exams (echocardiography, chest X-ray, electrocardiogram and cardiac angiography) that they believe to be useful for the correct diagnosis of this clinical situation. Additionally, the authors make a brief review of the literature relevant to the case. 相似文献
106.
M. E. Martín Hortigüela J. M. Ribó Cruz N. Ventura Gómez 《Pediatric surgery international》1992,7(2):146-148
The term cast syndrome is used to denote duodenal obstruction occurring after application of a corrective plaster cast to patients with scoliosis. We report a classical case in a 14-year-old female who required surgical intervention after conservative treatment failed. Six months later the patient had no further gastrointestinal symptoms. Clinical, radiological, and pathological details as well as the surgical treatment are described and discussed.
Offprint requests to: M. E. Martín Hortigüela 相似文献
107.
M Alvarez R Granados D Mauleón G Rosell M Salas J Sallés N Valls 《Journal of medicinal chemistry》1987,30(7):1186-1193
The synthesis and irreversible alpha-blocking activity in the rat vas deferens of a series of tetra- and diamine disulfides 2-38, structural analogues of benextramine (BHC), are described. All compounds containing a central cystamine moiety displayed an irreversible alpha-adrenergic blockade at concentrations ranging from 10(-4) to 6 X 10(-6)M. Potency was increased in cystamines N,N'-disubstituted with 6-aminohexyl groups, especially when the outer nitrogen atoms bear arylalkyl substituents or are enclosed in a ring. However, N,N,N',N'-tetrasubstituted cystamines were poor blockers. Structural specificity in the outer portion of the tetramine disulfide is low, since many types of substituents gave rise to potent alpha-blockers. Even replacement of the outer amines with nonbasic ethers or amides was observed to maintain irreversible alpha-blockade. 相似文献
108.
An evaluation of the cardiovascular safety profile of duloxetine: findings from 42 placebo-controlled studies. 总被引:3,自引:0,他引:3
Joachim Wernicke Alberto Lledó Joel Raskin Daniel K Kajdasz Fujun Wang 《Drug safety》2007,30(5):437-455
BACKGROUND AND OBJECTIVE: In recent years, new classes of medication, such as the serotonin-noradrenaline reuptake inhibitors (SNRIs), have been developed for use in the treatment of major depressive disorder (MDD). For many years, treatment options were largely limited to the use of monoamine oxidase inhibitors (MAOIs), tricyclic antidepressants (TCAs) and selective serotonin reuptake inhibitors (SSRIs). However, there have been published reports of orthostatic hypotension, arrhythmias and corrected QT (QTc) interval changes in patients treated with TCAs. As new medications become available, it is important to understand how their cardiovascular safety profile compares with that of more established agents to aid clinicians and patients in choosing the best treatment options. This study was designed to evaluate the cardiovascular safety profile of the SNRI duloxetine through evaluation of cardiovascular-related parameters and adverse events (AEs). METHODS: The cardiovascular safety of duloxetine was assessed using all placebo-controlled duloxetine clinical trial data as of December 2005. This consisted of data from 42 placebo-controlled clinical trials of 8504 patients who were treated with duloxetine. Additional information from a high-dose clinical pharmacology study and postmarketing safety surveillance are also presented. Of the placebo-controlled trials included in this analysis, clinical indications under investigation included MDD (15 studies), diabetic peripheral neuropathic pain (3 studies), fibromyalgia (2 studies), generalised anxiety disorder (3 studies) and lower urinary tract disorders (19 studies, all related to incontinence). Cardiovascular safety was evaluated based on vital signs, ECGs and the incidence of treatment-emergent AEs potentially related to cardiovascular safety. These safety parameters were analysed across all indications. To identify both serious and non-serious cardiovascular-related AEs, as well as AEs reported as the reason for discontinuation, a comprehensive list of terms derived from the Medical Dictionary for Regulatory Activities (version 8.0) was generated and used to search the duloxetine databases for cardiovascular-related events. RESULTS: Calculation of change from baseline to maximum in ECG parameters showed significant differences between treatment groups for all parameters, with decreases from baseline in RR, QRS and QT intervals for patients receiving duloxetine and increases from baseline for patients treated with placebo. These shifts were related to small heart rate changes, but the mean differences were not considered clinically relevant. Categorical analyses of shifts from normal to abnormal (or abnormal to normal) for heart rate and QT corrected for heart rate using Fridericia's formula (QTcF) values showed that most patients did not shift from their baseline category. Patients with MDD who were treated for up to 1 year with duloxetine had blood pressure changes early in treatment that then stabilised. Even in patients with elevated blood pressure at baseline in these clinical trials, no increased risk of sustained blood pressure elevation with duloxetine treatment was found. CONCLUSION: Overall, the findings presented here support our conclusions that use of duloxetine does not appear to be associated with significant cardiovascular risks in patients with conditions for which the drug has been approved or studied. 相似文献
109.
110.
F Arreola R Paniagua J Herrera S Díaz-Bensussen L Mondragón J A Bermúdez E Pérez Pastén S Villalpando 《Archives of andrology》1986,16(2):151-154
Plasma zinc and pituitary and testicular hormone concentrations were measured in two groups of male adolescents. One group comprised insulin-dependent diabetes mellitus patients, aged 14-19 years; the other, as control, included 12 healthy youngsters aged 13-19 years. Plasma concentration of zinc, prolactin, testosterone, and dihydrotestosterone were lower in diabetics than in controls, whereas the ratios of androstenedione and androstenedione to testosterone + dihydrotestosterone were higher. Plasma FSH and LH were normal. These results suggest a diminished conversion of androstenedione to testosterone and relate zinc with the 17-beta-hydroxysteroid dehydrogenase enzyme activity. 相似文献