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51.
Antiserum-agar plate method for simultaneous detection and direct isolation of Legionella species in clinical and environmental specimens. 下载免费PDF全文
Colonies of Legionella pneumophila serotypes 1 through 6, L. micdadei, L. bozemanii, L. dumoffii, and L. gormanii, which were developed on filtered yeast extract agar containing polyvalent antiserum, were surrounded by distinct, specific precipitin rings. 相似文献
52.
Raci Karayigit Alireza Naderi Firat Akca Carlos Janssen Gomes da Cruz Amir Sarshin Burak Caglar Yasli Gulfem Ersoz Mojtaba Kaviani 《Nutrients》2021,13(1)
Caffeine is widely consumed among elite athletes for its well-known ergogenic properties, and its ability to increase exercise performance. However, studies to date have predominantly focused on the anhydrous form of caffeine in male participants. The aim of the study was to investigate the effect of caffeinated coffee ingestion on lower-upper body muscular endurance, cognitive performance, and heart rate variability (HRV) in female athletes. A total of 17 participants (mean ± standard deviation (SD): age = 23 ± 2 years, body mass = 64 ± 4 kg, height = 168 ± 3 cm) in a randomized cross-over design completed three testing sessions, following the ingestion of 3 mg/kg/bm of caffeine (3COF), 6 mg/kg/bm of caffeine (6COF) provided from coffee or decaffeinated coffee (PLA) in 600 mL of hot water. The testing results included: (1) repetition number for muscular endurance performance; (2): reaction time and response accuracy for cognitive performance; (3): HRV parameters, such as standard deviation of normal-to-normal (NN) intervals (SDNN), standard deviation of successive differences (SDSD), root mean square of successive differences (RMSSD), total power (TP), the ratio of low- and high-frequency powers (LF/HF), high-frequency power (HF), normalized HF (HFnu), low-frequency power (LF), and normalized LF (LFnu). A one-way repeated measures ANOVA revealed that 3COF (p = 0.024) and 6COF (p = 0.036) improved lower body muscular endurance in the first set as well as cognitive performance (p = 0.025, p = 0.035 in the post-test, respectively) compared to PLA. However, no differences were detected between trials for upper body muscular endurance (p = 0.07). Lastly, all HRV parameters did not change between trials (p > 0.05). In conclusion, ingesting caffeinated coffee improved lower body muscular endurance and cognitive performance, while not adversely affecting cardiac autonomic function. 相似文献
53.
Feng You-Shan Kohlmann Thomas Janssen Mathieu F. Buchholz Ines 《Quality of life research》2021,30(3):647-673
Quality of Life Research - Although the EQ-5D has a long history of use in a wide range of populations, the newer five-level version (EQ-5D-5L) has not yet had such extensive experience. This... 相似文献
54.
Extragranular storage of the neuron blocking agent meta-iodobenzylguanidine (MIBG) in human neuroblastoma cells 总被引:1,自引:0,他引:1
Human SK-N-SH neuroblastoma cells accumulate and store the adrenal imaging agent metaiodobenzylguanidine (MIBG) with minor involvement of specialized cytoplasmic storage granules (Smets LA et al., Active uptake and extravesicular storage of meta-iodo-benzylguanidine in human neuroblastoma SK-N-SH cells. Cancer Res 49: 2941-2944, 1989). In the present study the mechanism of extravesicular MIBG retention was investigated and compared with granular storage of MIBG and norepinephrine (NE) in PC-12 pheochromocytoma cells. SK-N-SH cells concentrated both MIBG and NE by neuron-specific Uptake-1 but long-term retention was only observed with MIBG. Retention of accumulated NE was, however, promoted by inhibition of intracellular catecholamine degradation with pyrogallol. Drug release by controlled cell permeabilization and by KCl-induced exocytosis indicated that MIBG was mainly stored as freely diffusible, cytoplasmic molecules. SK-N-SH cells were depleted from stored MIBG by the Uptake-1 inhibitor imipramine but poorly so by the granule-depleting drug reserpine. Conversely, PC-12 cells were depleted by reserpine but insensitive to imipramine. The data suggest that extravesicular retention of MIBG in SK-N-SH cells is not based on intracellular sequestration but is solely due to efficient re-uptake of accumulated drug after leaking from the cells. The accumulation of MIBG in SK-N-SH cells, reflecting "pure" Uptake-1, appears to be a powerful system for exploring various cellular and molecular aspects of catecholamine uptake. 相似文献
55.
van Griethuysen AJ Janssen AJ van Noort M Verbrugh HA Diepersloot RJ 《International journal of antimicrobial agents》1995,5(3):183-186
Loracarbef (LC) is the first clinically available carbacephem. In order to evaluate the antimicrobial activity of LC, a total of 593 clinical strains of H. influenzae, M. catarrhalis, S. pneumoniae and S. pyogenes were collected by seven participating study centres. Minimal inhibitory concentrations for loracarbef and amoxycillin-clavulanic acid combination (AC) were determined by a microdilution method. The MIC-90 of beta-lactamase-negative strains of H. influenzae was 2.0 (LC) and 0.5 (AC), and for beta-lactamase-positive strains 4.0 (LC) and 2.0 (AC) mg/l. For beta-lactamase-negative and beta-lactamase-positive strains of M. catarrhalis, the MIC-90 results were 0.5 and 2.0 (LC) and 0.13 and 0.5 (AC) mg/l. The MIC-90 for AC was =0.03 for both S. pneumoniae and S. pyogenes, while the LC results were 0.5 and 0.25 mg/l, respectively. Of all strains tested, only one beta-lactamase-positive isolate of H. influenzae was shown to be resistant to LC and another one to be resistant to AC. The MICs for both AC and LC were significantly higher in H. influenzae and M. catarrhalis strains isolated in the centre and in the south-east of The Netherlands. In conclusion, the results of this study indicate that loracarbef can be used in the initial therapy of community acquired respiratory infections. 相似文献
56.
Janssen T Raviv G Camby I Petein M Darro F Pasteels J Schulman C Kiss R 《International journal of oncology》1995,7(5):1219-1225
The influence of dihydrotestosterone (DHT), the epithelial growth factor (EGF) and the basic fibroblast growth factor (bFGF) was investigated on LNCaP, DU145 and PC3 cell growth, which represents the ratio between cell gain (cell proliferation) and cell loss (cell death). In the present study, cell growth was assessed by means of the computer-assisted microscope analysis of Feulgen-stained nuclei combined with the mathematical Delaunay triangulation and Voronoi paving techniques, which enabled the cell colony patterns, i.e. their density and level of organisation, to be determined. The results from a previous study (Janssen et al, Prostate, in press) combined with those of the present one show that DHT was found to activate proliferation of the LNCaP model, as evidenced by increase in size of colonies, increase in number of cells within colonies, increase in cell colony density and, accordingly, decrease in mean segment length value (which is the distance between adjacent cell nuclei). Using the same criteria, DHT was found inhibitory on growth of DU145 cell line, and devoid of significant effect on PC3 cell line. Basic FGF was found to be a powerful stimulator of growth of PC3 cell Line and to induce a weaker stimulation of DU145 cell line. On LNCaP cell line, it increased the size of colonies without increase of the number of cells per colony. This feature can be explained by a decrease in cell colony density. With respect to the same colonies, the proliferation index (percentage of cells in the S+G2 phases of the cell cycle) was found similar to that of the controls. This suggests that the increase in the size of the colonies is due to a difference of spreading of the cells on their supports. EGF had no significant effect on LNCaP and PC3 models, and was decreasing cell density of DU145 colonies. 相似文献
57.
This study among Dutch nurses (N = 156) tested Leiter's 1993 process model of burnout. The LISREL results of this study partially support Leiter's model. It appeared that emotional exhaustion was primarily related with the demand variable work overload while depersonalization was, to a lesser degree, associated with the resource variable coworker support. Personal accomplishment was significantly related with coping and emotional exhaustion was associated with depersonalization. However, Leiter's model did not fit to the data in all respects. Modifications indices provided by LISREL 8 suggested to relax the relationship between: (1) coping and depersonalization and (2) social support and emotional exhaustion. Because these relationships were supported by both theory and existing empirical evidence, they were successively added to the model. Eventually, the model improved considerably and all selected criteria were met. Several relationships in the final model, however, were nonsignificant (e.g., the relationship between personal accomplishment and autonomy and participation, respectively). 相似文献
58.
Janssen HL van Buuren HR Leebeek FW Schalm SW 《Nederlands tijdschrift voor geneeskunde》1999,143(41):2037-2041
Portal vein thrombosis (PVT) has a heterogeneous aetiology. Recently discovered thrombotic risk factors such as latent myeloproliferative disorders and prothrombotic genetic defects are important in the aetiology of PVT. At least one-third of the PVT patients exhibit a combination of thrombotic risk factors. Treatment with anticoagulant drugs has not proved beneficial for most PVT patients. Therapy with anticoagulants is only recommended in those with acute PVT, in those who recently underwent a portosystemic shunt procedure and in those with other thrombotic manifestations, particularly in case of proved hypercoagulability. Due to intact coagulation, oesophageal varices bleeding in patients with PVT has a better prognosis than in cirrhotics. 相似文献
59.
The motivational characteristics of psychotherapy inpatients should be of crucial importance for treatment effectiveness. In the present study on 219 patients from two psychosomatic-psychotherapeutic treatment centers, four dimensions of motivation for psychotherapy (illness experience; lay etiology; treatment expectations; openness to psychotherapy) were assessed using the Questionnaire for the Measurement of Psychotherapy Motivation (Fragebogen zur Messung der Psychotherapiemotivation; FMP) and related to pre-post changes in symptomatology. In these analyses, psychological symptoms (SCL-90-R) as well as interpersonal problems (IIP) were considered as indicators of treatment effects. The results support the expectation that (a) a psychosocial causal attribution of illness symptoms and (b) a marked general openness to psychotherapy at the pretreatment interview predict more positive treatment outcomes. Implications of the results for the indication of pretreatment interventions are discussed. 相似文献
60.
Veerhuis R Janssen I De Groot CJ Van Muiswinkel FL Hack CE Eikelenboom P 《Experimental neurology》1999,160(1):289-299
Complement activation products C1q, C4c/d, and C3c/d in amyloid plaques in Alzheimer's disease probably result from direct binding and activation of C1 by amyloid beta peptides. RT-PCR and in situ hybridization studies have shown that several complement factors are produced in the brain parenchyma. In the present study, cytokines that can be detected in amyloid plaques (i.e., interleukin (IL)-1, IL-6, and tumor necrosis factor (TNF)-alpha) were found to differentially stimulate the expression of C1 subcomponents, C1-Inhibitor (C1-Inh), C4, and C3, by astrocyte and microglial cell cultures derived from postmortem adult, human brain specimens and by neuroblastoma cell lines in culture. C1r and C1s were secreted at low levels by astrocytes and neuroblastoma cell lines. Exposure of cells to IL-1 alpha, IL-1 beta, TNF-alpha and to a far lesser extent IL-6, markedly upregulated C1r, C1s, and C3 production. C4 synthesis increased in response to interferon (IFN)-gamma and IL-6, whereas that of C1-Inh could be stimulated only by IFN-gamma. Thus, C1-Inh production is refractory to stimulation by plaque-associated cytokines, whereas these cytokines do stimulate C1r, C1s, and also C4 and C3 secretion by astrocytes and neuronal cells in culture. In contrast to the amyloid plaque associated cytokines IL-1 beta, IL-1 alpha, and TNF-alpha, the amyloid peptide A beta 1-42 itself did not stimulate C1r and C1s synthesis by astrocytes, microglial cells, or neuroblastoma cell lines. Microglial cells were the only cell type that constitutively expressed C1q. The ability of C1q to reassociate with newly formed C1r and C1s upon activation of C1 and subsequent inactivation by C1-Inh, may enable ongoing complement activation at sites of amyloid deposition, especially when C1-Inh is consumed and not replaced. 相似文献