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1.
Typha latifolia L. from aquatic plants is widely found throughout Kehli Stream (Elazig, Turkey). This study examined the uptake of some metals by T. latifolia and the transfer from roots to other plant parts. The accumulation of Mn in T. latifolia L. can be suggested as a tolerance strategy due to its transfer factor higher than 1.0. The enrichment coefficients in the leaves of T. latifolia L. were higher than 1.0 for Zn and Mn and often lower than 1.0 for other metals. Similarly, the enrichment coefficients of all metals, except for Cr, in roots of T. latifolia L. were higher than 1.0. This study demonstrated that T. latifolia L. could be considered as either a bio-indicator or a bio-accumulator for sediments and water polluted by metals.  相似文献   
2.
Allopatric isolation in glacial refugia has caused differentiation and speciation in many taxa globally. In this study, we investigated the nuclear and mitochondrial genetic differentiation of the long fingered bat, Myotis capaccinii during the ice ages in south-eastern Europe and Anatolia. The mitochondrial DNA (mtDNA) analyses indicated a suture zone similar to those recorded in other animal species, including bats, suggesting the association of more than one refugium with the region. Contrary to most of the other species where a suture zone was seen in Anatolia, for M. capaccinii the geographical location of the genetic break was in south-eastern Europe. This mitochondrial differentiation was not reflected in the nuclear microsatellites, however, suggesting that the lack of contact during the ice ages did not result in reproductive isolation. Hence taxonomically, the two mitochondrial clades cannot be treated as separate species.  相似文献   
3.
Molecular and Cellular Biochemistry - Excitation–contraction coupling in normal cardiac function is performed with well balanced and coordinated functioning but with complex dynamic...  相似文献   
4.
Zusammenfassung Die Fortpflanzungsperiode der Palmtaube (Streptopelia s. senegalensis L.) fängt in Diyarbakir/Türkei (37°55N/40°12E) schon Anfang Februar an und kann bis Mitte November dauern. In diesem Zeitraum kann ein Paar bis zu sieben Bruten beginnen (Tab. 1). Nach der Paarbildung fangen die Kopulationen an, die vor allem in der Woche vor der Eiablage stark zunehmen. Während des Brütens und der ersten Woche der Jungenaufzucht sind sie dagegen nicht zu beobachten. Sie werden vom im allgemeinen mit sog. Flügeltippen bzw. Scheinputzen eingeleitet. Nach der Begattung paradiert das um das , das auf der Stelle verharrt. Vor dem Tretakt fällt das dagegen in infantiles Verhalten und bettelt unter Flügelzittern den Partner um Futter an. Es bekommt auch tatsächlich Futter. Die Palmtauben sind zumindest für eine Fortpflanzungssaison monogam. U. a. spielen wechselseitige Gefiederpflege und Anschlußbruten sowie die Fütterung des durch das eine wichtige Rolle für das Zusammenleben und -bleiben der Partner. Der Nistplatz wird vom gezeigt, aber vom gewählt. Das Nistmaterial wird vom eingetragen und im allgemeinen vom alleine in das Nest eingefügt. Nur während des Brutwechsels bringt auch das hin und wieder Nistmaterial, das aber wahrscheinlich nur für den Partner, nicht für das Nest dient. In den späteren Phasen des Brütens gilt dies wahrscheinlich auch für das . 1–4 Tage nach dem Nestbaubeginn wird gegen Abend das erste Ei gelegt, womit auch das Brüten anfängt. Das zweite Ei folgt dann rund 38 Stunden später.
On the reproductive behaviour of the Laughing Dove (Streptopelia senegalensis): pair-formation to egg-laying
Summary In Diyarbakr/Turkey, the reproductive season of the Laughing Dove begins in early February and lasts til mid November. One pair may start with breeding up to seven times a year. The frequency of copulations which could be observed only after pair formation increased considerably in the week before incubation starts. During incubation and during the first week of the nestling period no copulations could be observed. Usually copulations are initiated by the male pecking behind its folded wings (displacement-preening). Before mating, the female turns into infantile behaviour begging food from its partner by wing-twitching. Food is then delivered by the male. After mating the female parades around the male which stays motionless. Paired birds stay together at least during one reproductive season. Reinforcement of the pair bond will be achieved by mutual preening, courtship feeding of the female by the male, and successive broods. The male indicates the nest site which is successively chosen by the female. The nest material is brought by the male and usually placed by the female at the nest site. Only during change-overs the female sometimes brings nesting material, too. However, this material probably is for the partner, not actually for the nest. The same may be true for similar behaviour of the male in late stages of incubation. One to four days after nest building has started the first egg is laid, mostly in late afternoon. Incubation starts with the first egg; the second egg is laid about 38 hours later.
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5.
Summary Studies with the atypical muscarinic antagonist pirenzepine provide convincing evidence for the classification of muscarinic acetylcholine receptors (mAChRs) into two subtypes, M1 and M2. The present study examines the heterogeneity of the M2 subtype employing the newly developed competitive muscarinic antagonist, AFDX-116. Comparison of the binding affinities of pirenzepine, atropine, and AFDX-116 to mAChRs in microsomes from the rabbit cerebral cortex, heart, and iris smooth muscle shows that iris mAChRs, which are pharmacologically of the M2 subtype, can be distinguished from M2 cardiac receptors based on their affinity for AFDX-116. These results are consistent with the hypothesis that the M2 receptor subtype consists of a heterogeneous population of receptors.Abbreviations mAChRs Muscarinic Acetylcholine Receptors - CCh Carbachol - NMS N-Methylscopolamine - AFDX-116 11-[[2-[(diethylamino)methyl]-1-piperidinyl]acetyl]-5,11-dihydro-6Hpyrido[2,3-b][1,4]benzodiazepine-6-one  相似文献   
6.
Abstract: Effects of the neuropeptide corticotropin-(1–24) -tetracosapeptide (ACTH) on the endogenous and exogenous phosphorylation of lipids and endogenous phosphorylation of proteins were investigated in microsomes and a 110,000 ×g supernatant fraction [30–50% (NH4)2SO4 precipitate; ASP30–50] obtained from rabbit iris smooth muscle. Subcellular distribution studies revealed that both of these fractions are enriched in diphosphoinositide (DPI) kinase. The 32P labeling of lipids and proteins was measured by incubation of the subcellular fractions with [γ-32P]ATP. The labeled lipids, which consisted of triphosphoinositide (TPI), DPI, and phosphatidic acid (PA) were isolated by TLC. The microsomal and ASP30–50 fractions were resolved into six and nine labeled phosphoprotein bands, respectively, by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The basal labeling of both lipids and proteins was rapid (30–60 s), and it was dependent on the presence of Mg2+ in the incubation medium; in general it was inhibited by high concentrations (>0.2 mM) of Ca2+. ACTH stimulated the labeling of TPI and inhibited that of PA in a dose-dependent manner, with maximal effect observed at 50–100 μ of the peptide. ACTH appears to increase TPI labeling by stimulating the DPI kinase. Under the same experimental conditions ACTH (100 μM) inhibited significantly the endogenous phosphorylation of six microsomal phosphoproteins (100K, 84K, 65K, 53K, 48K, and 17K). In the ASP30–50 fraction, ACTH inhibited the phosphorylation of three phosphoproteins (53K, 48K, and 17K) and stimulated the labeling of six phosphoprotein bands (117K, 100K, 84K, 65K, 42K, and 35K). The effects of ACTH on lipid and protein phosphorylation are probably Ca2+-independent; thus the neuropeptide effects were not influenced by either 1 μM EGTA or low concentrations of Ca2+ (50 μ.M). We conclude that a relationship may exist between polyphosphoinositide metabolism and protein phosphorylation in the rabbit iris smooth muscle.  相似文献   
7.
This study aimed to investigate the protective effects of arbutin (ARB) against brain injury induced in rats with potassium bromate (KBrO3). The rats were divided into four groups as Group 1: Control (0.9% NaCl ml/kg/day p.), Group 2: KBrO3 (100 mg/kg (gavage), Group 3: ARB (50 mg/kg/day p.), and Group 4: KBrO3 + ARB (100 mg/kg (gavage) + 50 mg/kg/day p.). At the end of the fifth day of the study, the rats in all groups were killed, and their brain tissues were collected. In the collected brain tissues, malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) levels were measured, and routine histopathological examinations were made. The MDA levels in the group that was exposed to KBrO3 were significantly higher than those in the control group (p ˂ 0.001). In comparison to the KBrO3 group, the MDA levels in the KBrO3 + ARB group were significantly lower (p ˂ 0.001). It was observed that SOD and CAT enzyme activity levels were significantly lower in the KBrO3 group compared to the control group (p ˂ 0.001), while these levels were significantly higher in the KBrO3 + ARB group than in the KBrO3 group (p ˂ 0.001). Additionally, the group that was subjected to KBrO3 toxicity, as well as ARB administration, had much lower levels of histopathologic signs than the group that was subjected to KBrO3 toxicity only. Consequently, it was found that KBrO3 exposure led to injury in the brain tissues of the rats, and using ARB was effective in preventing this injury.  相似文献   
8.
In this study, we investigated the combined treatment of 5-fluorouracil (5-FU) and Anatolian propolis extract (PE) on colorectal cancer (CRC)using in vitro and in vivo studies. We exposed luciferase-transfected (Lovo-Luc CRC) cells and healthy colon cells (CCD-18Co) to varying concentrations of 5-FU and PE to assess their genotoxic, apoptotic, and cytotoxic effects, as well as their intracellular reactive oxygen species (iROS) levels. We also developed a xenograft model in nude mice and evaluated the anti-tumor effects of PE and 5-FU using various methods. Our findings showed that the combination of PE and 5-FU had selectivity against cancer cells, particularly at higher doses, and enhanced the anti-tumor effectiveness of 5-FU against colon CRC. The results suggest that PE can reduce side effects and increase the effectiveness of 5-FU through iROS generation in a dose-dependent manner.  相似文献   
9.
10.
1. The mechanism of acetylcholine-stimulated breakdown of phosphatidyl-myo-inositol 4,5-bisphosphate and its dependence on extracellular Ca(2+) was investigated in the rabbit iris smooth muscle. 2. Acetylcholine (50mum) increased the breakdown of phosphatidylinositol bisphosphate in [(3)H]inositol-labelled muscle by 28% and the labelling of phosphatidylinositol by 24% of that of the control. Under the same experimental conditions there was a 33 and 48% increase in the production of (3)H-labelled inositol trisphosphate and inositol monophosphate respectively. Similarly carbamoylcholine and ionophore A23187 increased the production of these water-soluble inositol phosphates. Little change was observed in the (3)H radioactivity of inositol bisphosphate. 3. Both inositol trisphosphatase and inositol monophosphatase were demonstrated in subcellular fractions of this tissue and the specific activity of the former was severalfold higher than that of the latter. 4. The acetylcholine-stimulated production of inositol trisphosphate and inositol monophosphate was inhibited by atropine (20mum), but not tubocurarine (100mum); and it was abolished by depletion of extracellular Ca(2+) with EGTA, but restored on addition of low concentrations of Ca(2+) (20mum). 5. Calcium-antagonistic agents, such as verapamil (20mum), dibenamine (20mum) or La(3+) (2mm), also abolished the production of the water-soluble inositol phosphates in response to acetylcholine. 6. Release of inositol trisphosphate from exogenous phosphatidylinositol bisphosphate by iris muscle microsomal fraction (;microsomes') was stimulated by 43% in the presence of 50mum-Ca(2+). 7. The results indicate that increased Ca(2+) influx into the iris smooth muscle by acetylcholine and ionophore A23187 markedly activates phosphatidylinositol bisphosphate phosphodiesterase and subsequently increases the production of inositol trisphosphate and its hydrolytic product inositol monophosphate. The marked increase observed in the production of inositol monophosphate could also result from Ca(2+) activation of phosphatidylinositol phosphodiesterase. However, there was no concomitant decrease in the (3)H radioactivity of this phospholipid.  相似文献   
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