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61.
Prolonged, strenuous exercise may lead to suppressive effects on the immune system, which might be responsible for a greater susceptibility to opportunistic infections. The aim of this study was to examine the influence of carbohydrate substitution (CHS) during prolonged, strenuous exercise on neutrophil granulocytes and their oxidative burst (intracellular oxidation of dihydrorhodamine123 to rhodamine123 after induction by formylized 1-methionyl-1-leucyl-1-phenylalanin) using flow cytometry. In three trials different concentrations of CHS (placebo compared to 6% and 12% CHS; 50 ml·kg–1) were given randomly to 14 endurance trained cyclists [mean (SD) age 25 (5) years, maximal oxygen uptake 67 (6) ml·min–1·kg–1] cycling for 4 h in a steady state at 70% of their individual anaerobic threshold. Blood samples were taken before, immediately after cessation, 1 h and 19 h after exercise. A significant rise in neutrophil counts was observed immediately after cessation and 1 h after exercise with a return to normal rest values 19 h after exercise for all three conditions (P<0.001). The relative proportions of rhodamine123+ neutrophils were significantly diminished in all three conditions 1 h after exercise (P<0.01), while the mean fluorescence intensity was lowest in the placebo trial and differed significantly to the 12% CHS trial (P=0.024) and almost significantly to the 6% CHS trial (P=0.052). In conclusion, these data suggest a beneficial effect of CHS on the neutrophil oxidative burst and a possible attenuation of the susceptibility to infections, presumably due to the reduction of metabolic stress in prolonged, strenuous exercise. Electronic Publication  相似文献   
62.
Eighty-five patients undergoing cataract surgery were given for prophylaxis of intraocular infection two intravenous doses each of 200 mg, 300 mg or 400 mg ciprofloxacin (35 patients), 400 mg or 800 mg pefloxacin (30 patients), or 400 mg ofloxacin (20 patients). Ciprofloxacin levels in aqueous humour ranged from 0.02 to 0.50 µg/ml, pefloxacin levels from 1.04 to 7.80 µg/ml, and ofloxacin levels from 0.44 to 2.27 µg/ml with ratios of aqueous humour to serum levels ranging from 3.8 % to 25 %, 21 % to 48.1 % and 44 % to 88.4 %, respectively. It is concluded that the quinolones studied might be suitable for surgical prophylaxis or treatment of anterior chamber infections due toEnterobacteriaceae, while ciprofloxacin at high doses is preferable forPseudomonas aeruginosa infections.  相似文献   
63.
It is well known that neuronal firing properties are determined by synaptic inputs and inherent membrane functions such as specific ionic currents. To characterize the ionic currents of brainstem cardio-respiratory neurons, cells from the hypoglossal (XII) nucleus and the dorsal motor nucleus of the vagus (DMX) were freshly dissociated and membrane ionic currents were studied under whole-cell voltage and current clamp. Both of these neurons showed a TTX-sensitive Na+ current with a much larger current density in XII than DMX neurons. This Na+ current had two (fast and slow) distinct inactivation decay components. The ratio of the magnitudes of the fast to slow component was roughly two-fold greater in DMX than in XII cells. Both DMX and XII neurons also showed a high voltage-activated Ca2+ current, but this current density was significantly greater (three-fold) in DMX than XII neurons. A relatively small amount of low-voltage activated Ca2+ current was also observed in DMX neurons, but not in the majority of XII cells. A transient and a sustained outward current components were observed in DMX cells, but only sustained currents were present in XII neurons. These outward currents had a reversal potential of about − 70 mV with 3 mM external K+ and −30 mV with 25 mM K+, and substitution of K+ with cesium and tetraethylammonium suppressed more than 90% the outward currents, indicating that most outward currents were carried by K+. The transient outward current consisted of two components with onesensitive to 4-aminopyridine and the other to intracellular Ca2+. In XII neurons, BRL 38227 (lemakalim), an ATP-sensitive K+ (KATP) channel activator, increased the sustained K+ currents by 10% of control, and glibenclamide, a KATP channel blocker, decreased the sustained K+ currents by 20%. Evidence for the presence of an inward rectifier K+ current was also obtained from both XII and DMX neurons. These results on XII and DMX neurons indicate that (1) the methods used to dissociate neurons provide a useful means to overcome voltage clamp technical difficulties; (2) ion channel characteristics such as density and biophysical properties of DMX neurons are very different from those of XII neurons; and (3) several newly discovered membrane ionic currents are present in these cells.  相似文献   
64.
Summary Copovithane is an uncharged, water-soluble, synthetic polymer with an average molecular weight of 5800 daltons. It demonstrates antitumor activity in vivo against a variety of tumors in animal models but is inactive in vitro. This agent has been found to have immunorestorative activity in man. In concert with its phase I clinical trial, copovithane concentrations were analyzed by HPLC in plasma, urine, and autopsy and in tumor biopsy specimens obtained from patients. Copovithane was cleared from plasma biphasically with a mean t1/2 of 11.1±4 min and a t1/2 of 246±78 min at the dose of 1 g/m2, while the plasma half-lives increased to 57.7±12 and 718±149 for the alpha and beta phases, respectively, at the 10 g/m2 dose, demonstrating clear, dose-dependent pharmacokinetics. There were no significant differences between dose 1 and dose 4 pharmacokinetics. The apparent volume of distribution (Vd) was 14.5±1. at the 1 g/m2 dose and increased to 73 1. at the 33 g/m2 dose. The calculated mean clearance rate for copovithane in plasma was between 2.4 and 5.4 mg/kg x min and did not appear to be dose-dependent. The urinary excretion of copovithane was approximately 5% of the administered dose over 120 h at the 1 g/m2 dose and decreased to 1% at the 33 g/m2 dose. In seven tumor biopsy samples, concentrations of drug in tumor varied from 1- to 1000-fold higher than that found in concurrent plasma samples. In three autopsy samples, the highest concentrations were found in kidney, intestine, and liver, in decreasing order. These studies show that copovithane exhibits dose-dependent changes in pharmacokinetics at doses between 1 and 33 g/m2. However, copovithane does penetrate well to tumor tissues, achieving high tumor/plasma ratios. In addition, copovithane concentrations were highest in kidney tissue, which may be a site for potential organ toxicity.  相似文献   
65.
Dry extracts from the Eurasian plants, Ajuga turkestanica, Eurycoma longifolia, and Urtica dioica have been used as anabolic supplements, despite the limited scientific data on these effects. To assess their actions on early sarcopenia signs, male and female castrated mice were supplemented with lyophilized extracts of the three plants, isolated or in association (named TLU), and submitted to resistance exercise. Ovariectomy (OVX) led to body weight increase and non-high-density cholesterol (HDL) cholesterol elevation, which had been restored by exercise plus U. dioica extract, or by exercise and TLU, respectively. Orchiectomy (ORX) caused skeletal muscle weight loss, accompanied by increased adiposity, being the latter parameter reduced by exercise plus E. longifolia or U. dioica extracts. General physical activity was improved by exercise plus herbal extracts in either OVX or ORX animals. Exercise combined with TLU improved resistance to fatigue in OVX animals, though A. turkestanica enhanced the grip strength in ORX mice. E. longifolia or TLU also reduced the ladder climbing time in ORX mice. Resistance exercise plus herbal extracts partly altered gastrocnemius fiber size frequencies in OVX or ORX mice. We provide novel data that tested ergogenic extracts, when combined with resistance exercise, improved early sarcopenia alterations in castrated male and female mice.  相似文献   
66.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Versicherte haben seit 2019 einen gesetzlichen Anspruch auf Verordnung von digitalen Gesundheitsanwendungen (DiGA). Die...  相似文献   
67.
We investigated the genetic profiles of killer cell immunoglobulin-like receptors (KIRs) in Ebola virus–infected patients. We studied the relationship between KIR–human leukocyte antigen (HLA) combinations and the clinical outcomes of patients with Ebola virus disease (EVD). We genotyped KIRs and HLA class I alleles using DNA from uninfected controls, EVD survivors, and persons who died of EVD. The activating 2DS4–003 and inhibitory 2DL5 genes were significantly more common among persons who died of EVD; 2DL2 was more common among survivors. We used logistic regression analysis and Bayesian modeling to identify 2DL2, 2DL5, 2DS4–003, HLA-B-Bw4-Thr, and HLA-B-Bw4-Ile as probably having a significant relationship with disease outcome. Our findings highlight the importance of innate immune response against Ebola virus and show the association between KIRs and the clinical outcome of EVD.  相似文献   
68.
International Urology and Nephrology - Biomarkers for the diagnosis and monitoring treatment response of kidney cancer are urgently needed. Neutrophil gelatinase-associated lipocalin (NGAL) is a...  相似文献   
69.
International Urology and Nephrology - Delayed graft function (DGF) is a manifestation of acute kidney injury uniquely framed within the transplant process and a predictor of poor long-term graft...  相似文献   
70.
Background There is limited information about the clinical characteristics, treatment and outcome of maintenance hemodialysis patients with COVID-19. Moreover, regional differences are also conceivable since the extend and severity of outbreaks varied among countries.Methods In this retrospective, observational, single-center study, we analyzed the clinical course and outcomes of 37 maintenance hemodialysis patients (median age 64 years, 51% men) hospitalized with COVID-19 from 24 March to 22 May 2020 as confirmed by real-time PCR.Results The most common symptoms at admission were fatigue (51%), fever (43%), dyspnea (38%) and cough (35%). There were 59% mild/moderate patients and 41% severe/critical patients. Patients in the severe/critical group had a significantly higher atherosclerotic burden since diabetic kidney disease and vascular nephropathies were the most common primary kidney diseases and eighty percent of them had coronary heart disease. Also, Charlson comorbidity score was higher in this group. At admission chest X-ray, 46% had ground-glass abnormalities. Overall, 60% patients received hydroxychloroquine, 22% lopinavir–ritonavir, 11% tocilizumab, 24% systemic glucocorticoids, and 54% received prophylactic anticoagulation. Seven (19%) patients died during hospitalization and 30 were discharged. The main causes of death were cardiovascular (5 patients) and respiratory distress syndrome (2 patients). In Cox regression analysis, lower oxygen saturation, anemia and hypoalbuminemia at admission were associated with increased mortality.Conclusions In conclusion, we observed a high mortality rate among maintenance hemodialysis patients hospitalized for COVID-19. Anemia, lower serum albumin and lower basal oxygen saturation at admission were factors associated with poor prognosis.  相似文献   
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