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61.
We studied patterns of genetic relatedness and paternity in moustached tamarins, small Neotropical primates living in groups of 1–4 adult males and 1–4 adult females. Generally only one female per group breeds, mating with more than one male. Twin birth are the norm. In order to examine the genetic consequences of this mating pattern, DNA was extracted from fecal samples collected from two principal and six neighboring groups. DNA was characterized at twelve microsatellite loci (average: seven alleles/locus). We addressed the following questions: Do all adult males have mating access to the reproductive female of the group? How is paternity distributed across males in a group? Can polyandrous mating lead to multiple paternity? Are nonparental animals more closely related to the breeders than to the population mean? And, are mating partners unrelated? Breeding females mated with all nonrelated males. In at least one group the father of the older offspring did not sire the youngest infant although he was still resident in the group. We also found evidence for multiple paternity in a supposed twin pair. Yet, within each group the majority (67–100%) of infants had the same father, suggesting reproductive skew. Relatedness within groups was generally high (average R = 0.31), although both nonrelated males and females occurred, i.e., immigrations of both sexes are possible. Mating partners were never found to be related, hence inbreeding seems to be uncommon. The results suggest that while the social mating system is polyandry, paternity is often monopolized by a single male per group. Am J Phys Anthropol, 2005. © 2004 Wiley-Liss, Inc.  相似文献   
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This article describes the first patient with a deficiency of transaldolase (TALDO1 [E.C.2.2.1.2]). Clinically, the patient presented with liver cirrhosis and hepatosplenomegaly during early infancy. In urine and plasma, elevated concentrations of ribitol, D-arabitol, and erythritol were found. By incubating the patient's lymphoblasts and erythrocytes with ribose-5-phosphate and subsequently analyzing phosphate sugar metabolites, we discovered a deficiency of transaldolase. Sequence analysis of the transaldolase gene from this patient showed a homozygous deletion of 3 bp. This deletion results in absence of serine at position 171 of the transaldolase protein. This amino acid is invariable between species and is located in a conserved region, indicating its importance for enzyme activity. The detection of this new inborn error of pentose metabolism has implications for the diagnostic workup of liver problems of unknown etiology.  相似文献   
64.
Periodontitis is induced by periodontal dysbiosis characterized by the predominance of anaerobic species. TLRs constitute the classical pathway for cell activation by infection. Interestingly, the Toll/IL-1 receptor homology domain adapters initiate signaling events, leading to the activation of the expression of the genes involved in the host immune response. The aim of this study was to evaluate the effects of Porphyromonas gingivalis on the expression and protein-protein interactions among five TIR adapters (MAL, MyD88, TRIF, TRAM and SARM) in gingival epithelial cells and endothelial cells. It was observed that P. gingivalis is able to modulate the signaling cascades activated through its recognition by TLR4/2 in gingival epithelial cells and endothelial cells. Indeed, MAL-MyD88 protein-protein interactions associated with TLR4 was the main pathway activated by P. gingivalis infection. When transient siRNA inhibition was performed, cell viability, inflammation, and cell death induced by infection decreased and such deleterious effects were almost absent when MAL or TRAM were targeted. This study emphasizes the role of such TIR adapter proteins in P. gingivalis elicited inflammation and the precise evaluation of TIR adapter protein interactions may pave the way for future therapeutics in both periodontitis and systemic disease with a P. gingivalis involvement, such as atherothrombosis.  相似文献   
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66.
Reperfusion after ischemic conditions induces massive endothelial cell (EC) activation, an initial step of reperfusion injury. Reperfusion is characterized by reoxygenation, realkalinization and a localized increase of inflammatory stimuli. In this study, we focused on the influence of extracellular realkalinization on human umbilical vein endothelial cell (HUVEC) activation. We examined intracellular pH (pH(in)) and intracellular free calcium concentration ([Ca(2+)](in)), a second messenger known to mediate von Willebrand factor (VWF) exocytosis in endothelium, upon realkalinization. Furthermore, we measured the agonist-stimulated exocytosis of VWF, Interleukin-8 and soluble P-selectin (sP-Selectin) as markers of EC activation. To verify a morphological correlate of EC activation, we finally observed platelet-endothelial adherence during realkalinization using shear flow. Realkalinization of HUVEC was simulated by switching from bicarbonate buffered Ringer solution of an acidotic pH(ex) of 6.4 to a physiologic pH(ex) of 7.4. Extracellular realkalinization was accompanied by pH(in) recovery from 6.5 to 7.2 within 10 min. Application of cariporide, an inhibitor of the Na(+)/H(+) exchanger subtype 1 (NHE), during extracellular realkalinization significantly delayed the early kinetics of intracellular realkalinization. Histamine stimulated [Ca(2+)](in) was significantly increased upon realkalinization compared to control cells. Also agonist-stimulated release of VWF, Interleukin-8 and sP-Selectin was massively enhanced during pH(in) recovery in comparison to control. Furthermore, we observed an increased platelet binding to endothelium. Interestingly, each of these realkalinization-induced effects were significantly reduced by early application of cariporide. Therefore, delay of acute NHE-dependent pH(in) recovery may represent a promising mechanism for inhibition of EC activation upon reperfusion.  相似文献   
67.
At present, carbon nano-materials are being utilized in various procedures, especially in laser desorption/ionization-mass spectrometry (LDI-MS) for analyzing a range of analytes, which include peptides, proteins, metabolites, and polymers. Matrix-oriented LDI-MS techniques are very well established, with weak organic acids as energy-absorbing substances. Carbon materials, such as nano-tubes and fullerenes are being successfully applied in the small-mass range, where routine matrices have strong background signals. In addition, the role of carbon nano-materials is very well established in the fractionation and purification fields. Modified diamond powder and surfaces are utilized in binding peptides and proteins from complex biological fluids and analyzed by matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS). Polylysine-coated diamond is used for solid-phase extraction to pre-concentrate DNA oligonucleotides. Graphite is useful for desalting, pre-concentration, and as energy-absorbing material (matrix) in desorption/ionization. Carbon nano-tubes in their different derivatized forms are used as matrix materials for the analysis of a range of analytes, such as carbohydrates, amino acids, peptides, proteins, and some environmental samples by LDI-MS. Fullerenes are modified in different ways to bind serum entities analyzed through MALDI/TOF-MS and are subsequently utilized in their identifications. In addition, the fullerenes are a promising matrix in LDI-MS, but improvements are needed.  相似文献   
68.
Sleeping sites are an important aspect of an animal's ecology given the length of time that they spend in them. The sleep ecology of wild saddleback and mustached tamarins is examined using a long-term data set covering three mixed-species troops and 1,300+ tamarin nights. Seasonal changes in photoperiod accounted for a significant amount of variation in sleeping site entry and exit times. Time of exit was more closely correlated with sunrise than time of entry was with sunset. Both species entered their sleeping sites when light levels were significantly higher than when they left them in the morning. Troops of both species used >80 individual sites, the majority being used once. Mustached tamarins never used the same site for more than two consecutive nights, but saddlebacks reused the same site for up to four consecutive nights. Mustached tamarins slept at significantly greater heights than saddleback tamarins. There were consistent interspecific differences in the types of sites used. Neither the presence of infants, season, nor rainfall affected the types or heights of sites chosen. Sleeping sites were located in the central area of exclusive use more often than expected, and their position with respect to fruiting trees indicated a strategy closer to that of a multiple central place forager than a central place forager. These findings are discussed in light of species ecology, with particular reference to predation risk, which is indicated as the major factor influencing the pattern of sleeping site use in these species.  相似文献   
69.
Dispersal and philopatry influence gene flow and thus the spatio-genetic structure within and between populations. In callitrichids the flexible social and mating system corresponds with a variable migration pattern where both sexes might be philopatric or might disperse. We investigated the relationship between the spatio-genetic structure and migration patterns in a population of mustached tamarins, Saguinus mystax. Using the rapidly evolving hypervariable region I (HVI) of the mitochondrial control region and 11 microsatellite markers we detected a high variation (HVI: 16 haplotypes in 69 individuals; microsatellites: H(O) = 0.75, average: 7.45 alleles/locus), with mating partners usually not sharing the same haplotype, indicating that matings are generally between partners that are not closely related. Similar high variance of haplotype differences for male-male and female-female pairs, along with a slightly higher number of haplotype differences in males show that both sexes habitually migrate. Spatial analyses suggest that females usually migrate longer distances, corresponding to very limited breeding positions for females in a polyandrous social mating system.  相似文献   
70.
Understanding the evolution of mating systems, a central topic in evolutionary biology for more than 50 years, requires examining the genetic consequences of mating and the relationships between social systems and mating systems. Among pair-living mammals, where genetic monogamy is extremely rare, the extent of extra-group paternity rates has been associated with male participation in infant care, strength of the pair bond and length of the breeding season. This study evaluated the relationship between two of those factors and the genetic mating system of socially monogamous mammals, testing predictions that male care and strength of pair bond would be negatively correlated with rates of extra-pair paternity (EPP). Autosomal microsatellite analyses provide evidence for genetic monogamy in a pair-living primate with bi-parental care, the Azara''s owl monkey (Aotus azarae). A phylogenetically corrected generalized least square analysis was used to relate male care and strength of the pair bond to their genetic mating system (i.e. proportions of EPP) in 15 socially monogamous mammalian species. The intensity of male care was correlated with EPP rates in mammals, while strength of pair bond failed to reach statistical significance. Our analyses show that, once social monogamy has evolved, paternal care, and potentially also close bonds, may facilitate the evolution of genetic monogamy.  相似文献   
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