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101.
The placement of radio- and GPS-collars on primates has advanced the fields of primate behavior and ecology and yielded considerable conservation gains. However, to ensure that the placement of tracking collars remains a humane practice, the reporting of both positive and negative outcomes is required. Here, we evaluate the impacts of radio-collars on the reproduction, behavior, and health of female mantled howlers (Alouatta palliata) on Barro Colorado Island, Panama. In June 2005, as part of a behavioral study, we fitted 16 female howlers with ball-chain radio-collars weighing 1.2% of the mean adult female weight. We monitored these 16 collared females and 64 noncollared females across an annual cycle, and recaptured the collared females in July 2006 for collar removal. The mortality rate for collared females across the study year was 6.3% (N=1), while the net loss of noncollared females from study groups was 15.6% (N=10). All collared females reproduced. The behaviors of collared and noncollared females were not significantly different. However, on recapture to remove all remaining collars (N = 13), 38% of recaptured collared females presented with damage to the dermal layer on the back of the neck and 31% presented with more severe damage extending into the subcutaneous tissue and muscle. Given this physical damage, which was not apparent through binoculars, we cannot recommend using ball-chain radio-collars on female mantled howlers without careful welfare monitoring.  相似文献   
102.
The mark/rouge test has been used to assess mirror self‐recognition (MSR) in many species. Despite consistent evidence of MSR in great apes, genetic or non‐genetic factors may account for the individual differences in behavioral responses that have been reported. We examined whether vasopressin receptor gene (AVPR1A) polymorphisms are associated with MSR‐related behaviors in chimpanzees since vasopressin has been implicated in the development and evolution of complex social relations and cognition and chimpanzees are polymorphic for the presence of the RS3‐containing DupB region. We compared a sample of DupB+/? and DupB?/? chimpanzees on a mark test to assess its role on social behavior toward a mirror. Chimpanzees were administered two, 10‐min sessions where frequencies of mirror‐guided self‐directed behaviors, contingent actions and other social behaviors were recorded. Approximately one‐third showed evidence of MSR and these individuals exhibited more mirror‐guided self‐exploratory behaviors and mouth contingent actions than chimpanzees not classified as passers. Moreover, DupB+/? males exhibited more scratching and agonistic behaviors than other male and female cohorts. Our findings support previous studies demonstrating individual differences in MSR abilities in chimpanzees and suggest that AVPR1A partly explains individual differences in MSR by influencing the behavioral reactions of chimpanzees in front of a mirror.  相似文献   
103.
Endothelial progenitor cells (EPC) participate in revascularization and angiogenesis. EPC can be cultured in vitro from mononuclear cells of peripheral blood, umbilical cord blood or bone marrow; they also can be transdifferentiated from mesenchymal stem cells (MSC). We isolated EPCs from Wharton's jelly (WJ) using two methods. The first method was by obtaining MSC from WJ and characterizing them by flow cytometry and their adipogenic and osteogenic differentiation, then applying endothelial growth differentiating media. The second method was by direct culture of cells derived from WJ into endothelial differentiating media. EPCs were characterized by morphology, Dil-LDL uptake/UEA-1 immunostaining and testing the expression of endothelial markers by flow cytometry and RT-PCR. We found that MSC derived from WJ differentiated into endothelial-like cells using simple culture conditions with endothelium induction agents in the medium.  相似文献   
104.
Studying genetic mechanisms underlying primate brain morphology can provide insight into the evolution of human brain structure and cognition. In humans, loss‐of‐function mutations in the gene coding for ASPM (Abnormal Spindle Microtubule Assembly) have been associated with primary microcephaly, which is defined by a significantly reduced brain volume, intellectual disability and delayed development. However, less is known about the effects of common ASPM variation in humans and other primates. In this study, we characterized the degree of coding variation at ASPM in a large sample of chimpanzees (N = 241), and examined potential associations between genotype and various measures of brain morphology. We identified and genotyped five non‐synonymous polymorphisms in exons 3 (V588G), 18 (Q2772K, K2796E, C2811Y) and 27 (I3427V). Using T1‐weighted magnetic resonance imaging of brains, we measured total brain volume, cerebral gray and white matter volume, cerebral ventricular volume, and cortical surface area in the same chimpanzees. We found a potential association between ASPM V588G genotype and cerebral ventricular volume but not with the other measures. Additionally, we found that chimpanzee, bonobo, and human lineages each independently show a signature of accelerated ASPM protein evolution. Overall, our results suggest the potential effects of ASPM variation on cerebral cortical development, and emphasize the need for further functional studies. These results are the first evidence suggesting ASPM variation might play a role in shaping natural variation in brain structure in nonhuman primates.  相似文献   
105.
106.
Journal of Mammalian Evolution - Mammalian dental formulae often are highly conserved, at least at a generic level. In walruses (Odobenus rosmarus), the constraints of dentition in light of...  相似文献   
107.
Plant and Soil - Shifts of plant community composition with enhanced atmospheric nitrogen (N) deposition in grasslands have occurred globally. Despite extensive studies on the effects of enhanced N...  相似文献   
108.
Luminescent lanthanide (III) ions have been exploited for circularly polarized luminescence (CPL) for decades. However, very few of these studies have involved chiral samarium (III) complexes. Complexes are prepared by mixing axial chiral ligands (R/S))‐2,2’‐bis(diphenylphosphoryl)‐1,1′‐binaphthyl (BINAPO) with europium and samarium Tris (trifluoromethane sulfonate) (Eu (OTf)3 and Sm (OTf)3). Luminescence‐based titration shows that the complex formed is Ln((R/S)‐BINAPO)2(OTf)3, where Ln = Eu or Sm. The CPL spectra are reported for Eu((R/S)‐BINAPO)2(OTf)3 and Sm((R/S)‐BINAPO)2(OTf)3. The sign of the dissymmetry factors, gem, was dependent upon the chirality of the BINAPO ligand, and the magnitudes were relatively large. Of all of the complexes in this study, Sm((S)‐BINAPO)2(OTf)3 has the largest gem = 0.272, which is one of the largest recorded for a chiral Sm3+ complex. A theoretical three‐dimensional structural model of the complex that is consistent with the experimental observations is developed and refined. This report also shows that (R/S)‐BINAPO are the only reported ligands where gem (Sm3+) > gem (Eu3+).  相似文献   
109.
Intrasexual competition is an important selective force that can favor the evolution of honest signals of fighting ability. Research has focused predominantly on male birds, but many female birds also possess plumage ornaments that could mediate the outcome of competitive interactions. We examined the relationship between blue and white structural coloration and aggression in female tree swallows Tachycineta bicolor. Tree swallows are secondary cavity nesters and females show delayed plumage maturation which may be related to intense competition for nest sites. We compared plumage reflectance of second‐year (SY) and after‐second year (ASY) females, and within‐individual changes in plumage reflectance of ASY females in two successive years. We assessed aggression by placing a caged SY female 2 m from the nest box of an ASY female and quantified the ASY female's response in relation to her own plumage coloration. We found substantial differences in plumage reflectance of SY and ASY females, but found that ASY females became greener with duller white coloration in the second year. This may be due to poor weather that made reproduction particularly costly in the first year of the study and suggests coloration is influenced by condition. We found no relationship between dorsal coloration and aggressiveness. Rather, brighter white females spent more time on their nest box and within 2 m of the intruder than females with dull breasts. Our findings suggest that brighter white ASY females may perceive a SY female as less of a threat or that there may be a trade‐off associated with aggression and parental care that is related to white brightness.  相似文献   
110.
为了合理利用羌活和宽叶羌活的药用植物资源,同时保护其物种多样性,该研究利用SSR分子标记技术对羌活与宽叶羌活邻域及异域分布的23个自然种群,共计227个个体进行多样性和种间分化研究.结果显示:(1)两个物种具有中等水平的遗传多样性;羌活的平均等位基因数(Na)、有效等位基因数(Ne)和期望杂合度(He)分别为2.603...  相似文献   
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