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171.
Genera of the Cephennomicrus group of the Cephenniini (Scydmaenitae) are revised, and the following new taxa are described: Trichokrater gen.n. , Trichokrater ekkentros sp.n. (type species of Trichokrater) (Borneo), Cephennococcus gen.n. , Cephennococcus kuchingensis sp.n. (type species of Cephennococcus) (Borneo), Cephennococcus kenyirensis sp.n. (West Malaysia), Cephennococcus crassus sp.n. (Borneo), Cephennococcus minutissimus sp.n. (West Malaysia), Pomphopsilla gen.n. , Pomphopsilla luhya sp.n. (type species of Pomphopsilla) (Kenya) and Pomphopsilla soror sp.n. (Kenya). Unique subcuticular pockets with setose openings on the pronotum of Trurlia and Trichokrater are identified as glandular structures. Enigmatic internal prothoracic cavities are described for the first time in Scydmaeninae (in Cephennococcus, Pomphopsilla and a female of an undescribed genus from Sulawesi); their fine structure and function remain unknown. Parsimony‐based cladistic analysis of the adult morphology of genera of Cephenniini provided robust evidence for a monophyly of the Cephennomicrus group, composed of Cephennomicrus, Cephennula, Lathomicrus, Pomphopsilla, Cephennococcus, Trurlia, Trichokrater and two undescribed Oriental genera known from females only; this distinct and well‐supported lineage is a sister group of Cephennodes + Hlavaciellus. The genus Cephennomicrus represented in the analysis by species belonging to three previously postulated species groups is not monophyletic, and a comprehensive study comprising more taxa is necessary to reclassify this heterogeneous group.  相似文献   
172.
The pigmented cells in Malpighian tubules of Drosophila melanogaster contain yellow globules which are blackened by osmium tetroxide. Permanent preparations of the tubules showing pigmentation can thus be made. Following prestaining acid hydrolysis, osmium-fixed tubules can be stained with orcein. For observations on pigment distribution and Feulgen-DNA content in the same preparation, tubules are fixed in mercuric chloride. Color remains visible for several hours in unfixed tubules mounted in modified buffered Ringer solution.  相似文献   
173.
To evaluate breastfed infants' responses to scented objects, we videotaped the facial and bodily reactions of sixty-three infants as they explored, in succession, three toys that were identical in appearance but different in their characteristic odor. Two of the toys were scented with odorants previously shown to be transmitted to human milk, one with ethanol and the other with vanilla, whereas the third toy was unscented. Each videotape was subjected to frame-by-frame analysis to measure a variety of behaviors that are considered either to be exploratory in nature in that they lead to perceptual information about the object or to reflect the infants' hedonic reaction. Analyses of these behaviors revealed that the infants looked more and vocalized less in the presence of the vanilla-scented toy and spent less time manipulating the ethanol-scented toy when compared with the unscented toy. Moreover, differential exposure to the odors of ethanol and vanilla, as indicated by differential consumption of alcohol by a parent or use of vanilla-scented product by the mother, was related to differential responses to these odors. These findings suggest that human infants are able to detect and retain information about the chemical features of their environment.   相似文献   
174.
Defects of load‐bearing connective tissues such as articular cartilage and intervertebral disc (IVD) can result from trauma, degenerative, endocrine, or age‐related disease. Current surgical and pharmacological options for the treatment of arthritic rheumatic conditions in the joints and spine are ineffective. Cell‐based surgical therapies such as autologous chondrocyte transplantation (ACT) have been in clinical use for cartilage repair for over a decade but this approach has shown mixed results. This review focuses on the potential of mesenchymal stem cells (MSCs) as an alternative to cells derived from patient tissues in autologous transplantation and tissue engineering. Here we discuss the prospects of using MSCs in regenerative medicine and summarize the advantages and disadvantages of these cells in articular cartilage and IVD tissue engineering. We discuss the conceptual and practical difficulties associated with differentiating and pre‐conditioning MSCs for subsequent survival in a physiologically harsh extracellular matrix, an environment that will be highly hypoxic, acidic, and nutrient deprived. Implanted MSCs will be exposed to traumatic physical loads and high levels of locally produced inflammatory mediators and catabolic cytokines. We also explore the potential of culture models of MSCs, fully differentiated cells and co‐cultures as “proof of principle” ethically acceptable “3Rs” models for engineering articular cartilage and IVD in vitro for the purpose of replacing the use of animals in arthritis research. J. Cell. Physiol. 222:23–32, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
175.
Summary Goldfish were trained to perform a conditioned avoidance response in a shuttle tank at acclimation temperatures between 10 °C and 35 °C. A high level of success (85–100%) was maintained over a relatively wide range of test temperatures, although outside this range the response was rapidly and reversibly blocked. The upper and lower thermal limits for the avoidance response were determined in goldfish acclimated to temperatures between 10 °C and 35 °C. The absolute thermal limits for the avoidance response in goldfish were approximately 3 °C to 42 °C, but the range for individuals was considerably more restricted. Increased acclimation temperature resulted in higher upper and lower thermal limits and thus constitutes a reasonable resistance adaptation. Over the lower range of acclimation temperatures the upper thermal limit showed greater mobility, whereas over the upper range of acclimation temperatures the lower thermal limits showed greater mobility. Goldfish acclimated to 5 °C and 38.5 °C exhibited very reduced % success at their respective acclimation temperatures even though they showed high % success when the same individuals were previously acclimated to less stressful temperatures. These extreme acclimation temperatures probably represent the absolute limits for chronic exposure.  相似文献   
176.
We have examined the actions of the potent GnRH antagonist [N-acetyl-D beta Na11-D-pCl-Phe2-D-Phe3-D-Arg6,Phe7,Arg8-D-Ala10]NH2GnRH++ + (GnRHa) on basal and GnRH-stimulated LH secretion, inositol phospholipid turnover, and intracellular Ca2+ levels in dispersed rat anterior pituitary tissue. As expected, GnRHa was found to be a pure antagonist of secretion, but was paradoxically equipotent with GnRH in stimulating inositol phospholipid turnover. Examination of intracellular Ca2+ changes at the single cell level using digital video-enhanced fluorescence imaging demonstrated that dispersed rat pituitary cells appeared to contain three GnRH analog-responsive cell populations: those that increased intracellular Ca2+ in response to both GnRH and GnRHa, and those that responded to either GnRH or GnRHa only. These observations were extended to studies of the relatively homogeneous gonadotroph cell populations of endocrinologically inactive pituitary adenomas. Of five adenomas examined, one increased inositol phospholipid turnover in response to GnRHa plus GnRH, but not GnRH alone, three responded to GnRH only, and one responded to both GnRH and GnRHa. Our findings, therefore, suggest that three GnRH analog-responsive cell types are also present in human pituitary and that clonal expansion of any of these cell types may be responsible for tumor formation.  相似文献   
177.
Genera of Eutheiini are reviewed and Eutheimorphus is removed from this tribe of ant‐like stone beetles (Scydmaeninae) and transferred to Cephenniini. A monogeneric Marcepaniini trib.n. is described to accommodate Marcepania gen.n. from Malaysia, with five species: M. semengohensis sp.n. (the type species of Marcepania), M. tuberculata sp.n. , M. seramaensis sp.n. , M. minutissima sp.n. and M. elongata sp.n. A phylogenetic analysis of all genera of Cephenniini, Eutheiini and Marcepaniini based on adult morphological characters resulted in recovering a well‐supported monophyletic clade Eutheiini + (Marcepaniini + Cephenniini) and these tribes are included in Cephenniitae stat.n. (Eutheiini and Cephenniini are therefore removed from Scydmaenitae). Only a weak support for monophyly of Eutheiini was found, but morphological characters allow for maintaining this presumably relic group as a separate tribe. Previously proposed monophyletic groups within Cephenniini were recovered as such, but after inclusion of Eutheimorphus, a sister taxon to the ‘Cephennomicrus group’, the latter lineage gained weak statistical support. The evolutionary history of Cephenniitae is discussed, with focus on known northern hemisphere fossils classified in Scydmaenitae and Hapsomelitae, but possibly closely allied to Cephenniitae. Establishing the supertribe Cephenniitae is the first step toward a profound reclassification of Scydmaeninae on a robust phylogenetic basis. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:B0E1B12D-9587-4C4F-A908-A12A0C424A8C .  相似文献   
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