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1.
The effects of MIF-1 administered into a lateral ventricle of the brain were studied on the behaviour of mice in the open field test and hole test, apomorphine-induced stereotypy, morphine-induced catalepsy, and reactivity on thermal painful stimuli in the hot plate test. The last test was compared with a similar test with morphine administration. It was demonstrated that MIF-1 exerted a depressing effect on the behaviour of mice, increased the intensity of apomorphine-induced stereotypy and weakened chlorpromazine-induced catalepsy. Moreover, an analgesic action of MIF-1 was demonstrated which was blocked with naloxone. The results of these investigations indicated a significant central action of MIF-1 in mice and a participation of dopaminergic receptors in certain effects of MIF-1 on the behaviour of experimental animals. 相似文献
2.
Robert Brus Dalibor Ballian Faruk Bogunić Martin Bobinac Marilena IdžOjtić 《Plant biosystems》2013,147(2):278-285
Abstract In most European countries, the service tree (Sorbus domestica L.) is a rare and threatened species and its conservation has been recognised as a priority. The aim of this study was to asses its morphologic variation in the western and central part of the Balkan Peninsula and in southern Central Europe. Three populations were analysed: one in Serbia, one in Bosnia and Herzegovina and one in Slovenia. In each population 30 trees were selected, and from each tree 30 leaves were collected for morphometric analysis based on nine leaflet morphological traits. Univariate (ANOVA) and multivariate (MANOVA) analysis of variance were used to estimate the variation within- and between populations and a discriminant analysis was performed to examine the structure of the between-population differences. The values of particular morphological traits found in our study did not differ considerably from the values reported elsewhere. The results revealed significant within- and between population variation. Variation within populations was highly significant for all the scored leaf morphological traits, while variation between populations was significant for all the studied traits except for the leaflet length. The discrimination between the three populations was significant. High percentages of correctly classified samples demonstrate good discriminating employability of the analysed leaf morphological traits and indicate differentiation of the analysed populations. 相似文献
3.
Neuroprotective and neurotoxic roles of levodopa (L-DOPA) in neurodegenerative disorders relating to Parkinson's disease 总被引:2,自引:0,他引:2
Summary. Despite its being the most efficacious drug for symptom reversal in Parkinson's disease (PD), there is concern that chronic
levodopa (L-DOPA) treatment may be detrimental. In this paper we review the potential for L-DOPA to 1) autoxidize from a catechol
to a quinone, and 2) generate other reactive oxygen species (ROS). Overt toxicity and neuroprotective effects of L-DOPA, both
in vivo and in vitro, are described in the context of whether L-DOPA may accelerate or delay progression of human Parkinson's
disease.
Received June 29, 2001 Accepted August 6, 2001 Published online June 3, 2002 相似文献
4.
5.
To determine the effect of prenatal lead exposure on brain monoaminergic systems, pregnant rats were given tap water containing
250 ppm lead acetate, for the duration of pregnancy, while tap water without lead (Pb2+) was substituted at birth. Control rats were derived from dams that consumed tap water during pregnancy, and had no exposure
to lead afterwards. At 12 weeks after birth, Pb2+ content of brain cortex was increased 3- to 4-fold (P < 0.05). At this time the endogenous striatal levels of 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid were
19% lower in Pb2+ exposed rats (P < 0.05), while there was no change in the striatal level of dopamine (DA), noradrenaline, 3,4-dihydroxyphenylglycol, serotonin
(5-HT) and 5-hydroxyindoleacetic acid (HPLC/ED). Also there was no change in these monoamines and metabolites in the prefrontal
cortex of Pb2+ exposed rats. However, turnover of 5-HT in prefrontal cortex, as indicated by 5-hydroxytryptophan accumulation 30 min after
acute treatment with the decarboxylase inhibitor NSD-1015 (100 mg/kg IP), was lower in the Pb2+ exposed rats. In the striatum AMPH-induced (1 mg/kg IP) turnover of DA, evidenced as L-DOPA accumulation after NSD-1015,
was increased to a lesser extent in the Pb2+ exposed rats (P < 0.05). The nitric oxide synthase inhibitor 7-nitroindazole (10 mg/kg IP) attenuated the latter effect, indicating that
neuronal NO mediates this AMPH effect, at least in part. Moreover, DA D2 receptor sensitivity developed in Pb2+ exposed rats, as evidenced by enhanced quinpirole-induced yawning activity and enhanced quinpirole-induced locomotor activity
(each, P < 0.05). These findings indicate that ontogenetic exposure to lead can have consequences on monoaminergic neuronal function
at an adult stage of life, generally promoting accentuated behavioral effects of direct and indirect monoaminergic agonists,
and related to increased dopamine turnover in basal ganglia.
Special issue dedicated to Dr. Moussa Youdim. 相似文献
6.
7.
M. Naiserová K. Kubová J. Vysloužil S. Pavloková D. Vetchý M. Urbanová J. Brus J. Vysloužil P. Kulich 《AAPS PharmSciTech》2018,19(2):681-692
Burst drug release is often considered a negative phenomenon resulting in unexpected toxicity or tissue irritation. Optimal release of a highly soluble active pharmaceutical ingredient (API) from hypromellose (HPMC) matrices is technologically impossible; therefore, a combination of polymers is required for burst effect reduction. Promising variant could be seen in combination of HPMC and insoluble Eudragits® as water dispersions. These can be applied only on API/insoluble filler mixture as over-wetting prevention. The main hurdle is a limited water absorption capacity (WAC) of filler. Therefore, the object of this study was to investigate the dissolution behavior of levetiracetam from HPMC/Eudragit®NE matrices using magnesium aluminometasilicate (Neusilin® US2) as filler with excellent WAC. Part of this study was also to assess influence of thermal treatment on quality parameters of matrices. The use of Neusilin® allowed the application of Eudragit® dispersion to API/Neusilin® mixture in one step during high-shear wet granulation. HPMC was added extragranularly. Obtained matrices were investigated for qualitative characteristics, NMR solid-state spectroscopy (ssNMR), gel layer dynamic parameters, SEM, and principal component analysis (PCA). Decrease in burst effect (max. of 33.6%) and dissolution rate, increase in fitting to zero-order kinetics, and paradoxical reduction in gel layer thickness were observed with rising Eudragit® NE concentration. The explanation was done by ssNMR, which clearly showed a significant reduction of the API particle size (150–500 nm) in granules as effect of surfactant present in dispersion in dependence on Eudragit®NE amount. This change in API particle size resulted in a significantly larger interface between these two entities. Based on ANOVA and PCA, thermal treatment was not revealed as a useful procedure for this system. 相似文献
8.
Niva A. Ran John A. Love Michael C. Heiber Xuechen Jiao Michael P. Hughes Akchheta Karki Ming Wang Viktor V. Brus Hengbin Wang Dieter Neher Harald Ade Guillermo C. Bazan Thuc‐Quyen Nguyen 《Liver Transplantation》2018,8(5)
Organic bulk heterojunction (BHJ) solar cells require energetic offsets between the donor and acceptor to obtain high short‐circuit currents (JSC) and fill factors (FF). However, it is necessary to reduce the energetic offsets to achieve high open‐circuit voltages (VOC). Recently, reports have highlighted BHJ blends that are pushing at the accepted limits of energetic offsets necessary for high efficiency. Unfortunately, most of these BHJs have modest FF values. How the energetic offset impacts the solar cell characteristics thus remains poorly understood. Here, a comprehensive characterization of the losses in a polymer:fullerene BHJ blend, PIPCP:phenyl‐C61‐butyric acid methyl ester (PC61BM), that achieves a high VOC (0.9 V) with very low energy losses (Eloss = 0.52 eV) from the energy of absorbed photons, a respectable JSC (13 mA cm?2), but a limited FF (54%) is reported. Despite the low energetic offset, the system does not suffer from field‐dependent generation and instead it is characterized by very fast nongeminate recombination and the presence of shallow traps. The charge‐carrier losses are attributed to suboptimal morphology due to high miscibility between PIPCP and PC61BM. These results hold promise that given the appropriate morphology, the JSC, VOC, and FF can all be improved, even with very low energetic offsets. 相似文献
9.
Community structure of insect herbivores is driven by conservatism,escalation and divergence of defensive traits in Ficus
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Martin Volf Scott E. Miller Brus Isua Mentap Sisol Gibson Aubona Petr Šimek Martin Moos Juuso Laitila Jorma Kim Jan Zima Jr Jadranka Rota George D. Weiblen Stewart Wossa Juha‐Pekka Salminen Yves Basset Vojtech Novotny 《Ecology letters》2018,21(1):83-92
Escalation (macroevolutionary increase) or divergence (disparity between relatives) in trait values are two frequent outcomes of the plant‐herbivore arms race. We studied the defences and caterpillars associated with 21 sympatric New Guinean figs. Herbivore generalists were concentrated on hosts with low protease and oxidative activity. The distribution of specialists correlated with phylogeny, protease and trichomes. Additionally, highly specialised Asota moths used alkaloid rich plants. The evolution of proteases was conserved, alkaloid diversity has escalated across the studied species, oxidative activity has escalated within one clade, and trichomes have diverged across the phylogeny. Herbivore specificity correlated with their response to host defences: escalating traits largely affected generalists and divergent traits specialists; but the effect of escalating traits on extreme specialists was positive. In turn, the evolution of defences in Ficus can be driven towards both escalation and divergence in individual traits, in combination providing protection against a broad spectrum of herbivores. 相似文献
10.
P Nowak R Brus J O?wiecimska A Soko?a R M Kostrzewa 《Journal of physiology and pharmacology》2002,53(2):251-263
The intracellular second messenger nitric oxide (NO) is implicated in a variety of physiological functions, including release and uptake of dopamine (DA). In the described study, in vivo microdialysis and differential pulse voltammetric techniques were used to determine the involvement of NO in release of DA and its metabolites (dihydroxyphenylalanine, DOPAC; homovanillic acid, HVA) in neostriatum of freely moving rats. While the NO donor molsidomine (30.0 mg/kg; MOLS) and neuronal NO synthase- (nNOS-) inhbitor 7-nitroindazole (10.0 mg/kg; 7-NI) had no effect on the basal in vivo microdialysate level of DA, 7-NI specifically enhanced D,L-amphetamine-(1.0 mg/kg i.p.; AMPH) evoked release of DA. Basal or AMPH effects on DOPAC and HVA levels were not influenced by MOLS or 7-NI. Findings indicate that nitrergic systems have an important role in mediating effects of AMPH on dopaminergic systems. 相似文献