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11.
Hogg S Hof M Würbel H Steimer T de Ruiter A Koolhaas J Sluyter F 《Behavior genetics》2000,30(6):439-446
Artificially selected aggressive (SAL) and non-aggressive (LAL) male house mice were tested in a hexagonal tunnel maze and light-dark preference (LD) box to determine if the bidirectional selection for aggressive behavior leads to a coselection for different levels of trait anxiety. The tunnel maze consists of an open, brightly lit central arena surrounded by a complex system of interconnecting tunnels. As in the LD box, animals which spend less time and are less active in the brightly illuminated section of the maze are considered to have higher anxiety levels. In the tunnel maze, the LAL mice showed more exploration and spent more time in the central arena than the SAL animals, but only during the final 2 min of the 6-min test. This reduced preference for the central arena was not due to general inactivity or a failure of the SAL to find the central arena and indicates a higher level of state anxiety in the aggressive animals. In contrast, no anxiety-like differences were found in the LD box, either for the percentage of time spent in the light compartment or for the number of crossings. SAL males actually showed higher levels of moving and rearing, and lower levels of freezing, than did LAL males. 相似文献
12.
H. Heuer Will Spijkers Thomas Kleinsorge Hanno van der Loo Christoph Steglich 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,118(3):381-392
We investigated the time course of the amplitude specification of rapid bimanual reversal movements (lateral displacements
on two digitizers). To this end we used the timed-response paradigm in which the response has to be initiated synchronously
with an auditory signal. Information about the required amplitudes was presented at various times before the synchronization
signal. Consistent with previous results, the progression of amplitude specification was reflected in the dependence of the
amplitudes of the reversal movements on the time interval between amplitude information and synchronization signal. Same or
different amplitudes for the hands were used to examine cross-talk at the programming level of the two-level model of intermanual
interference. The results indicate the existence of cross-talk in particular at short intervals between information about
amplitude and movement initiation. This is consistent with the notion that cross-talk between concurrent processes of amplitude
specification is transient and vanishes as the time available for motor programming increases.
Received: 28 August 1996 / Accepted: 10 July 1997 相似文献
13.
Expression of the interleukin (IL)-2 receptor β chain in the IL-7-dependent pre-B cell line I × N/2B permitted growth in presence of either IL-2 or IL-7, allowing for a direct comparison of intracellular signaling events. Protein tyrosine phosphorylation was essential for IL-2- and IL-7-induced signal transduction since the tyrosine kinase inhibitor herbimycin A blocked proliferation in response to both factors. Western blot analysis of tyrosine-phosphorylated proteins revealed that both IL-2 and IL-7 stimulation led to enhanced phosphorylation of proteins of 170-, 145, 115- and 99-kDa, as well as induction of phosphorylation of a 96-kDa protein. However, a 55- and a 155-kDa protein were only phosphorylated after IL-2 stimulation. The 55-kDa protein specifically phosphorylated by IL-2 could be identified as p52shc which has recently been shown to be critically involved in Ras activation. Shc tyrosine phosphorylation as a result of IL-2 stimulation was consistently found in CTLL-2 cells and human T lymphoblasts. Taken together our results indicate that the IL-2- and IL-7-stimulated intracellular pathways are partially different and that Shc is a target of IL2-, but not IL-7-, stimulated tyrosine phosphorylation. 相似文献
14.
Hanno Niess Nikolaus Börner Maximilian Muenchhoff Elham Khatamzas Manfred Stangl Alex Graf Philipp Girl Enrico Georgi Dionysios Koliogiannis Gerald Denk Michael Irlbeck Jens Werner Markus Guba 《American journal of transplantation》2021,21(4):1629-1632
To date, little is known about the duration and effectiveness of immunity as well as possible adverse late effects after an infection with SARS-CoV-2. Thus it is unclear, when and if liver transplantation can be safely offered to patients who suffered from COVID-19. Here, we report on a successful liver transplantation shortly after convalescence from COVID-19 with subsequent partial seroreversion as well as recurrence and prolonged shedding of viral RNA. 相似文献
15.
Edna H. G. Venneker Willem J. Remme MD PhD Diederik C. A. van Hoogenhuyze X. Hanno Krauss G. Louis Bartels Dick A. C. M. Kruijssen Cock J. Storm Dick van Schelven 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》1994,8(2):211-219
Summary Antiischemic effects of 1-blocking agents are based on intrinsic negative inotropic and chronotropic properties. Partial 1-agonistic activity, although useful in preserving cardiac function, may counteract such antischemic properties by modulating the intrinsic negative cardiac effects of beta-blockade. To investigate the acute hemodynamic and antiischemic profile of epanolol, a cardioselective 1-antagonist and partial agonist, 20 patients with left coronary artery disease underwent two incremental atrial pacing tests, 45 minutes before (APST I) and 15 minutes after (APST II) 4 mg intravenous epanolol, administered over 5 minutes. Additional measurements were carried out at 1, 3, 5, 10, and 15 minutes after epanolol, at basal and fixed heart rates. Epanolol immediately reduced heart rate with a maximum of 10% at 15 minutes and decreased contractility (Vmax) by 7% (both p<.05), whereas cardiac output fell temporarily by 9% (p<.05). Other hemodynamic parameters did not change, except for a significant 11% reduction in myocardial oxygen demand. Despite comparable pacing conditions, both the double product and contractility decreased significantly less during APST II, resulting in a 17% lower myocardial oxygen consumption (p<.05). Myocardial ischemia was markedly reduced, indicated by normalization of lactate metabolism [lactate extraction 16±7% vs. –7±8% (APST I)], less ST depression (21%), and modulation of LV end-diastolic pressure postpacing (all p<.05 vs. APST I), whereas angina was absent or less in 14 patients. None of the patients reported an adverse effect. Thus, under resting conditions intravenous epanolol induces moderate, short-lasting negative chronotropic and inotropic effects, but does not alter cardiac pump function or vascular resistance, reflecting its additional 1-agonistic properties. Alternatively, during pacing it still reduces ischemia through negative inotropic effects and diminishes myocardial oxygen demand, reflecting its 1-antagonistic profile. 相似文献
16.
The DD genotype of the ACE gene polymorphism is associated with progression of diabetic nephropathy to end stage renal failure in IDDM 总被引:1,自引:0,他引:1
Vleming LJ van der Pijl JW Lemkes HH Westendorp RG Maassen JA Daha MR van Es LA van Kooten C 《Clinical nephrology》1999,51(3):133-140
BACKGROUND: The insertion-deletion (I/D) polymorphism of the angiotensin converting enzyme gene is a diallelic polymorphism that constitutes a genetic influence on the progression of renal diseases such as IgA nephropathy. Patients with the DD genotype have an accelerated progression towards end stage renal failure in these diseases. The role of the I/D polymorphism in the pathogenesis of diabetic nephropathy in IDDM is unresolved. PATIENTS AND METHODS: We therefore set out to study the contribution of the I/D polymorphism in 79 patients (age 39.5 +/- 7.6 years (mean +/- SD) with end stage renal failure due to diabetic nephropathy, who were recipients of a combined kidney-pancreas transplantation (n = 60), or who were on the waiting list for such a procedure (n = 19). The control series consisted of 82 patients (age 39.5 +/- 9.6 years) without microalbuminuria after fifteen years of IDDM. RESULTS: The ACE genotype distribution in patients was not in accordance with the Hardy-Weinberg equilibrium due to a significant overrepresentation of the DD genotype (X2 = 8.9, p = 0.01). This resulted in a significant increase of the D-allele frequency in the cases compared to controls (X2 = 4.9, p = 0.03). The presence of one D-allele did not increase the risk of end stage renal failure (odds ratio ID/II = 1.0, 95% CI 0.4-2.2). The presence of the DD genotype increased the risk of end stage renal failure twofold compared to the other genotypes (odds ratio 2.1, 95% CI 1.1-4.0). The risk estimate seemed slightly higher in patients with good metabolic control (odds ratio 2.6, 95% CI 1.0-7.1), than in patients with poor control (odds ratio 1.6, 95% CI 0.59-4.3). CONCLUSION: It is concluded that the risk of end-stage renal failure in patients with IDDM is twofold increased in patients with the DD genotype as compared to patients with other genotypes. 相似文献
17.
M. Hanno F. Shofer R. Fritz S. Grant Mulholland A. J. Wein 《International urology and nephrology》1980,12(4):283-290
Six-thousand-seven-hunderd and forty-nine positive urine cultures from a large metropolitan Veterans Administration hospital were analyzed with respect to the organisms isolated and their antimicrobial sensitivies. A predicted therapeutic efficacy index was calculated for each antimicrobial agent tested. Gram-negative pathogens accounted for 84% of the infections. Proteus infections outnumbered those due to strains ofEscherichia coli. Gentamycin was found to be the most effective antimicrobial agent. 相似文献
18.
One of the primary antibacterial defense mechanisms of the bladder is the action of the luminal mucopolysaccharide layer against adsorption of inoculated bacteria. Previous studies have shown that local instillation of the mucopolysaccharide heparin can prevent bacterial adsorption on the bladder mucosa denuded of this "antiadherence factor." To determine whether this action was due to the mucopolysaccharide composition of heparin, or rather to its anticoagulant property, protamine sulfate (a basic protein with anticoagulant properties) was tested for antiadsorptive efficacy. Protamine offered no protection against bacterial adherence in the rabbit model. It appears that heparin's protective effect is unrelated to its action as an anticoagulant. 相似文献
19.
20.
B. Guigas J. E. de Leeuw van Weenen N. van Leeuwen A. M. Simonis‐Bik T. W. van Haeften G. Nijpels J. J. Houwing‐Duistermaat M. Beekman J. Deelen L. M. Havekes B. W. J. H. Penninx N. Vogelzangs E. van ‘t Riet A. Dehghan A. Hofman J. C. Witteman A. G. Uitterlinden N. Grarup T. Jørgensen D. R. Witte T. Lauritzen T. Hansen O. Pedersen J. Hottenga J. A. Romijn M. Diamant M. H. H. Kramer R. J. Heine G. Willemsen J. M. Dekker E. M. Eekhoff H. Pijl E. J. de Geus P. E. Slagboom L. M. ‘t Hart 《Diabetic medicine》2014,31(8):1001-1008