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61.
Herman Yeger Diane Forget Jennifer Alami Bryan R. G. Williams 《In vitro cellular & developmental biology. Animal》1996,32(8):496-504
Summary The temporal and spatial expression patterns of the Wilms tumor gene, WT1, were studied during the organogenesis of the mouse
kidneyin vitro. In situ hybridization and immunocytochemistry localized cellular expression of WT1 in whole kidney organ cultures to the induced
metanephric mesenchyme and developing podocytes. Organ cultures were further characterized immunocytochemically with antibodies
that specifically labeled the different tubular epithelial components and supporting mesenchyme of the developing nephrons.
In organ cultures, the WT1 expression pattern could be visualized in induced metanephric mesenchyme and entire cell cohorts
of differentiating podocytes. Expression of WT1 and cell specific markers were retained in short-term monolayer cultures of
dissociated kidneys. The development of the metanephric kidneyin vitro involves a highly restricted temporal and spatial cellular expression pattern of WT1 which closely follows that observed
in tissue sections from gestational kidney isolated during organogenesis in the mouse. 相似文献
62.
本文采用Y染色体特异的性别决定基因(Sry)作为新的细胞遗传标志,通过PCR技术来追踪观察造血干细胞的增殖与分化性能。该方法具有简便、灵敏和特异等优点。雌性受体小鼠输注雄鼠骨髓细胞和13天脾结节(CFU-S13)细胞后,Sry PCR测试受体小鼠的CFU-S结果表明,它们均为供体来源的XY细胞。用Sry PCR骨髓细胞和骨髓中脾结节生成细胞(CPU-S)的长期重建造血能力,结果表明,在存活雌性小鼠 相似文献
63.
B. D. Metscher R. Glenn Northcutt David M. Gardiner Susan V. Bryant 《Development genes and evolution》1997,207(5):287-295
Gene expression has been studied in considerable detail in the developing vertebrate brain, neural crest, and some placode-derived
organs. As a further investigation of vertebrate head morphogenesis, expression patterns of several homeobox-containing genes
were examined using whole-mount in situ hybridization in a sensory system primitive for the vertebrate subphylum: the axolotl
lateral lines and the placodes from which they develop. Axolotl Msx-2 and Dlx-3 are expressed in all of the lateral line placodes. Both genes are expressed throughout development of the lateral line system
and their expression continues in the fully developed neuromasts. Expression within support cells is highly polarized. In
contrast to most other observations of Msx genes in vertebrate organogenesis, expression of Msx-2 in developing lateral line organs is exclusively epithelial and is not associated with epithelial-mesenchymal interactions.
A Hox-complex gene, Hoxb-3, is shown to be expressed in the embryonic hindbrain and in a lateral line placode at the same rostrocaudal level, but not
in other placodes nor in mature lateral line organs. A Hox gene of a separate paralog group, Hoxa-4, is expressed in a more posterior hindbrain domain in the embryo, but is not expressed in the lateral line placode at that
rostrocaudal level. These data provide the first test of the hypothesis that the neurogenic placodes develop in two rostrocaudal
series aligned with the rhombomeric segments and patterned by combinations of Hox genes in parallel with the central nervous system.
Received: 2 April 1997 / Accepted: 2 July 1997 相似文献
64.
Barbara Lubec Zhuang Ya-hua Sainio Pertti Tuohimaa Pentti Erwin Kitzmüller Gert Lubec 《Life sciences》1997,60(26):618-2381
L-arginine and taurine are still in the center of physiological and pharmacological research. Although the fate of nitrogen of both compounds and of the 35S-taurine is well-documented, the fate of the carbon skeleton has not been elucidated yet. We studied the organ distribution of 14C arginine and 14C taurine over time in the mouse using whole body autoradiography with densitometric image analysis. We describe different organ distribution patterns. Kidney, heart, lung, the Harderian gland, the central nervous system, intestine and testis showed a comparable pattern of arginine disappearance in contrast to rapid disappearance in the salivary gland and the accumulation pattern in bone and spleen. Data on 14C taurine of liver, kidneys, lung, testis and Harderian gland resembled the arginine pattern; Accumulation of taurine carbon was found in salivary gland, bone, intestine, heart and brain. Our studies challenge and demand further related studies to obtaining more information on the fate of the carbon skeleton of these amino acids. 相似文献
65.
The distribution and morphology of crustacean cardioactive peptide-immunoreactive neurons in the brain of the locust Locusta migratoria has been determined. Of more than 500 immunoreactive neurons in total, about 380 are interneurons in the optic lobes. These neurons invade several layers of the medulla and distal parts of the lobula. In addition, a small group of neurons projects into the accessory medulla, the lamina, and to several areas in the median protocerebrum. In the midbrain, 12 groups or individual neurons have been reconstructed. Four groups innervate areas of the superior lateral and ventral lateral protocerebrum and the lateral horn. Two cell groups have bilateral arborizations anterior and posterior to the central body or in the superior median protocerebrum. Ramifications in subunits of the central body and in the lateral and the median accessory lobes arise from four additional cell groups. Two local interneurons innervate the antennal lobe. A tritocerebral cell projects contralaterally into the frontal ganglion and appears to give rise to fibers in the recurrent nerve, and in the hypocerebral and ingluvial ganglia. Varicose fibers in the nervi corporis cardiaci III and the corpora cardiaca, and terminals on pharyngeal dilator muscles arise from two subesophageal neurons. Some of the locust neurons closely resemble immunopositive neurons in a beetle and a moth. Our results suggest that the peptide may be (1) a modulatory substance produced by many brain interneurons, and (2) a neurohormone released from subesophageal neurosecretory cells. 相似文献
66.
The organization of the mucomicrovillar complex of the vomeronasal sensory epithelium of adult rats was examined using confocal laser scanning microscopy. In specimens labeled with the FITC-conjugated isolectin B4 of Bandeiraea simplicifolia, which recognizes terminal -galactose sugar residues of glycoconjugates, we demonstrated that the mucomicrovillar complex was composed of islet-like structures with a high-density -galactose core. The mucomicrovillar complex was further resolved into sensory and mucoid components in double-labeling and dual scanning experiments. The sensory component, which consists of the dendritic terminals of olfactory marker protein-immunoreactive vomeronasal receptor neurons, contained cytosolic glycoconjugates with terminal -galactose sugar residues. The extracellular mucoid component consisted of glycoconjugates containing terminal -galactose derived from the glands associated with the vomeronasal organ. These results demonstrated the complex microchemical organization of the sensory and mucoid components of the mucomicrovillar complex. 相似文献
67.
A. Falconi M. Borde A. Hernández-Cruz F. R. Morales 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1995,176(5):679-689
Stimulation of the spinal cord of the electric fish Gymnotus carapo, evoked an abrupt increase in the discharge rate of the electric organ. At the maximum of this response, the rate increased an average of 26 ± 11.8%. The duration of the response was 4.9 ± 2.12 s; its latency was 10.4 ± 1.1 ms. Activation of the Mauthner axon played a decisive role in this phenomenon as indicated by the following: (1) recordings from the axon cap of the Mauthner cell demonstrated that the response was evoked if the Mauthner axon was antidromically activated and (2) a response that was similar to that produced by spinal cord stimulation, was elicited by intracellular stimulation of either Mauthner cell. Stimulation of the eighth nerve could also increase the discharge rate of the electric organ. The effect was greater if a Mauthner cell action potential was elicited. The findings described in the present report, indicate the existence of a functional connection between the Mauthner cell and the electromotor system in Gymnotus carapo. This connection may function to enhance the electrolocative sampling of the environment during Mauthner-cell mediated behaviors. This is a novel function for the Mauthner cell.Abbreviations
EHP
extrinsic hyperpolarizing potential
-
EOD
electric organ discharge
-
M-AIR
Mauthner initiated abrupt increase in rate
-
M-cell
Mauthner cell
-
M-axon
Mauthner axon
-
PM
pacemaker nucleus
-
PM-cell
pacemaker cell
-
PPn
prepacemaker nucleus
-
SPPn
sublemniscal prepacemaker nucleus 相似文献
68.
69.
肝细胞生长因子mRNA在成年小鼠和人胎儿不同器官中的表达 总被引:2,自引:0,他引:2
本实验从成年小鼠和胎龄4-5月的人胎儿不同器官中分离总RNA。经斑点印迹分析显示,肝细胞生长因子(HGF)mRNA在成年KM小鼠多种器官中表达,其表达水平由高到低依次为:肺、肝、肾、卵巢、睾丸、大脑和胃;在脾、心、骨髓、小肠和骨骼肌组织中以HGFmRNA。在胎龄4-5月的人胎儿中,HGFmRNA表达水平由高到低依次为:大脑、肝、腮腺、胃、小肠、肾、心和骨骼肌;肺和脾组织为阴性。由此可见,HGF在成 相似文献
70.
K. Norrby S. Bergström P. Druvefors 《In vitro cellular & developmental biology. Plant》1984,20(8):607-614
Summary The intact membranous rat mesentery was cultured in Eagle's minimum essential medium containing no serum or only low concentrations
of serum. The procedure is in some important respects superior to previous organ culture techniques. To estimate the extent
of disturbance of homeostasis of the tissue in culture, the spontaneous mast-cell histamine release was quantitated after
preculture preparation of the specimens and after different intervals in culture. Also, the proliferation of fibroblasts and
mesothelial cells that predominate in the mesentery was assessed at 48 h by cytofluorometric quantitation of DNA in single-tissue
cells.
Spontaneous histamine release was time dependent during cultivation, amounting to ca. 50% at 48 h, and was affected by the
medium used for moistening the tissue before cultivation. Culturing also brought about great spontaneous increase in the proliferation
of fibroblasts and mesothelial cells, the rate being related to the concentration of serum. Addition of the mast-cell secretagogues
48/80 or polymyxin B at 1 h caused rapid release of 50 to 60% of the histamine and was followed by augmented proliferation
in the serum-containing media.
The spontaneous increase of cell proliferation in tissue culture may be causally related to mast-cell secretion. Further studies
are needed to define factors influencing the spontaneous mast-cell secretion and the mast-cell-dependent mitogenesis in normal
tissue cells
Supported by grants from the Swedish Medical Research Council (Project 5942) and State Board for Animal Experiments. 相似文献