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11.
In non Mg(2+)-loaded and non malaria-infected rat erythrocytes, mefloquine (100 micromol x l (-1)) stimulated choline/Mg2+ antiport without affecting the Na+/Mg2+ antiport. The stimulation of the choline/Mg2+ antiport by mefloquine, found in this study, and by trifluoperazine and fluvoxamine, reported previously [Ebel et al. Biochim Biophys Acta 2004; 1167: 132-40], was associated with CF3 groups attached to the quinoline or benzene ring. The effect of mefloquine on choline/Mg2+ antiport in vitro was not related to the antimalarial action of mefloquine in vivo. In rat erythrocytes, the choline/Mg2+ antiport can be differentiated from the Na+/Mg2+ antiport through the use of cinchonine that inhibited the choline/Mg2+ antiport [Ebel et al. Biochim Biophys Acta 2002; 1559: 135-44], and mefloquine that stimulated the choline/Mg2+ antiport, whereby the Na+/Mg2+ antiport was not affected by either drug at proper concentrations. The Na+/Mg2+ antiport and choline/Mg2+ antiports behave as different molecular entities.  相似文献   
12.
We report on the hypothalamic-pituitary-gonadal function in 2 male infants with the Smith-Lemli-Opitz (SLO or RSH) syndrome. Both infants had abnormal external genitalia. Basal and LHRH stimulated plasma gonadotropins were normal for age (1 month). Plasma testosterone, androstenedione, and dehydroepiandrosterone sulfate were normal for age and sex. Some forms of congenital adrenal hyperplasia (17,20-desmolase deficiency, 17α-hydroxylase deficiency, and 3β-hydroxysteroid dehydrogenase deficiency) were ruled out by hormonal studies. The endocrinological findings indicate a normal hypothalamic-pituitary-gonadal function and a normal adrenal steroid biosynthesis in these 2 patients. A partial androgen receptor defect causing the genital malformations seems possible in one patient. Whether 5α-reductase deficiency is the cause of the male pseudohermaphroditism in SLO syndrome remains the subject of future studies. © 1992 Wiley-Liss, Inc.  相似文献   
13.
Frozen shoulder is said to be a self-limiting entity but full recovery often takes more than 2 years. For that, most patients are unwilling to tolerate painful restriction while awaiting resolution. We prospectively investigated 30 patients (16 women, 14 men) for the outcome of arthroscopic capsular release in idiopathic frozen shoulder. Results were determined by the assessment of subjective and objective parameters to estimate both shoulder function and general health status. Symptoms persisted without improvement for a minimum of 6 months of conservative treatment. Preoperative average American shoulder and elbow surgeons score (ASES) was 35, visual analog scale (VAS) to measure pain was 7, and simple shoulder test (SST) was 4. Mean scores of the physical component of SF-36 were considerably reduced. Mean forward elevation was 85°, average abduction was 70°, mean internal rotation was 15°, and mean external rotation was 10°. Patients were followed-up at 6 weeks, 3, 6, 12 months and by a mean of 36 months. Range of motion for all planes improved (P < 0.05). Median VAS reduced to 2, average ASES increased to 91, and SST enhanced to a mean of 10 (P < 0.05). We stated improvement of the physical components in the SF-36 questionnaire in particular bodily pain and the role-physical score. There were no significant differences between the measurements in the early postoperative phase compared to the mid-term follow-up (P > 0.05). Our results demonstrate that arthroscopic release of refractory idiopathic frozen shoulder combined with a gentle manipulation provides reliable expectations for improvement in both clinical and general health status for most patients. We recommend the use of a limb-specific and a general-health-status questionnaire to conclude the benefit of the surgical intervention and contribute the optimization of a therapy concept more effectively.  相似文献   
14.
The cooperative therapy study MAKEI 83/86 included an examination of the prognostic value of the AFP in children and adolescents with extracranial non-testicular yolk sac tumors. The serum AFP values of 72 protocol- and follow-up-patients were documented at diagnosis and up to the ninth month of treatment. 32 of these patients had saccrococcygeal tumors, 27 had tumors of the ovary and 13 suffered from extragonadal germ cell-tumors. 4 children showed progressive disease under initial chemotherapy and 1 patient died of therapy, 10 of 72 patients relapsed. The AFP measurements were plotted on semilogarithmic charts. They were compared to the measurements of healthy children up to the age of 1 year. According to the development of the patients' AFP values compared to the reference curves the following classifications could be made: 1. Patients with a normal AFP-decrease id est 50% in less than or equal to 6 days during the 1st month of therapy: 48/72 patients 2. Patients with slow AFP-decrease: 17/72 patients 3. Patients with transient AFP-decrease: 5/72 patients 4. Patients with no AFP-decrease: 2/72 patients According to Kaplan-Meier life table analysis, patients with a normal AFP-decrease had an event-free survival of 89% +/- 4%, whereas all other patients showed an event-free survival of 63% +/- 10% (p less than 0.05). Regarding primary therapy id est tumor resection or preoperative chemotherapy an equal distribution of the patients among those with a normal and slow AFP-decrease was observed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
15.
Ambulatory blood pressure monitoring was applied in 27 pediatric patients aged 6.3 – 24.3 (median 15.0) years who had been transplanted 1.5 – 8.4 years previously. Daytime values were compared with the mean of 10 concomitant casual blood pressure recordings. At the time of the study, antihypertensive drugs were given to 17 patients. Inulin clearance ranged from 18 to 116 (median 66) ml/min per 1.73 m2. Ambulatory blood pressure monitoring confirmed hypertension or normotension determined by casual blood pressure measurements in 63% of patients. The physiological nocturnal dip in blood pressure was attenuated or reversed in 8 of 27 patients. It was reduced in all 3 patients with renal artery stenosis of the graft, in 3 of 4 patients with chronic rejection, in the only patient with recurrent focal segmental glomerulosclerosis, and in 1 of 6 patients with past acute rejection. The dipping was not related to inulin clearance. In conclusion, casual blood pressure measurements do not accurately reflect blood pressure in pediatric patients transplanted more than 1.5 years previously. A reduced nocturnal dip in blood pressure may indicate an underlying renovascular or renoparenchymal pathology. Ambulatory blood pressure monitoring should regularly be applied in patients with renal transplants. Received May 23, 1995; received in revised form June 18, 1996; accepted June 20, 1996  相似文献   
16.
Increased myocardial oxygen demand, induced by increased heart rate, may cause myocardial ischemia in the presence of significant coronary artery disease. Alterations in anesthetic depth or technique might put at risk or protect myocardium with compromised blood flow. In 20 dogs with critical left anterior descending coronary artery (LAD) stenosis, atrial pacing rates from 100 to 160 beats/min were achieved, with end-tidal halothane 0.7% (LowH) and 1.1% (HighH), end-tidal isoflurane 1.1% (LowI) and 1.5% (HighI), as well as with continuous fentanyl plus midazolam (FM) infusion anesthesia. Despite significantly different mean arterial and coronary perfusion pressures, rate-pressure product, and left ventricular dP/dtmax, the pacing rate at which systolic shortening decreased below the lower limit of the physiologic response, indicating regional dysfunction, was the same in all investigated anesthesia conditions (LowH: 127 +/- 4 beats/min; HighH: 128 +/- 5 beats/min; LowI: 125 +/- 4 beats/min; HighI: 122 +/- 5 beats/min; FM: 124 +/- 4 beats/min [mean +/- SEM], P greater than 0.05). None of the investigated anesthesia conditions either increased ischemia tolerance or showed a detrimental effect on myocardium with compromised coronary blood flow.  相似文献   
17.
In this book the editors give a broad overview of today's knowledge,policies and organization of blood transfusion with the goalto provide the clinician with essential information and practicaltips on how to rationalize and organize transfusion practicein their hospital. In the foreword, Marcela Contreras emphasizesthe increasing complexity and costs  相似文献   
18.
Background: Liver dysfunction as a result of impaired oxygen availability frequently occurs following hemorrhage and contributes to delayed mortality. Artificial oxygen carriers may improve oxygen supply to vital organs while avoiding the need for allogeneic transfusion.

Methods: Rats were subjected to hemorrhagic hypotension (mean arterial pressure = 35-40 mmHg for 120 min) and were subsequently resuscitated with (1) stored whole rat blood, (2) pentastarch, or (3) pentastarch combined with perflubron emulsion (PFE; 2.7 or 5.4 g/kg body weight), a second-generation artificial oxygen carrier. Recovery of liver adenosine triphosphate, hepatocellular injury, and expression of glutamine synthetase 1, a gene that is induced by exposure of hepatocytes to low partial pressure of oxygen, were studied at 4 h of resuscitation.

Results: Stored whole blood or pentastarch failed to restore liver adenosine triphosphate concentrations after prolonged shock as compared to sham controls and resulted in increased gene expression of glutamine synthetase 1. Addition of 2.7 g PFE/kg restored liver adenosine triphosphate to control, whereas 5.4 g PFE/kg resulted in adenosine triphosphate concentrations significantly above control. Improved hepatocellular oxygen supply was also confirmed by restoration of the physiologic expression pattern of glutamine synthetase 1. Serum enzyme concentrations were highest after resuscitation with stored blood, whereas addition of PFE failed to further decrease enzyme concentrations as compared to pentastarch alone.  相似文献   

19.
The following paper presents an investigation of the efficacy of piracetam in alcoholic organic mental disorder. A double-blind placebo-controlled study design was used to compare 2 dosages of the substance (2 X 3 g vs. 2 X 12 g). Cognitive function was assessed on days 0, 7, 14, 28, 42. Analysis of the results from 24 patients showed a clear-cut amelioration of cognitive functions in all 3 treatment groups. No difference could be demonstrated between the administration of placebo and the lower dose of piracetam. Patients on the higher dose showed an earlier improvement on one of the tests, but the final scores were similar in all three treatment groups.  相似文献   
20.
Abstract It has been suggested that cardioplegic arrest during cardiopulmonary bypass (CPB) produces global myocardial ischemia with a risk of myocardial stunning. It has also been postulated that anesthetic technique may affect the course of post-CPB myocardial stunning via exaggerated myocardial depression. However, we have previously found that global ventricular and regional myocardial responses to halothane do not differ in post-CPB and pre-CPB dogs. Our examination of the effects of CPB on the beta-adrenergic function revealed that beta-adrenergic receptor function is only slightly decreased immediately following (i.e., 1 min) and 30 minutes post-CPB. A dose-response relationship was established for dobutamine, with decreased responsiveness noted at both times. Since other data show normal inotropic stimulation of stunned myocardium, decreases in dobutamine responsiveness cannot be explained by beta-receptor desensitization. Overall, these data indicate that CPB does not result in myocardial stunning. The differences between these data and others showing myocardial stunning following CPB may be due to several factors, such as anesthetic regimen, lack of coronary blood flow abnormalities, and a reduction in sarcoplasmic reticular damage due to the hypothermic conditions used.  相似文献   
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