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81.
K. T. Kivistö H. K. Kroemer P. Fritz A. Linder G. Friedel P. Beaune 《Histochemistry and cell biology》1995,103(1):25-29
The cytochrome P450 (CYP) enzymes metabolize drugs and other xenobiotics in liver and also in some extrahepatic tissues. We have studied the expression and localization of CYP3A in primary lung tumours and normal lung tissue from the same patients. Thirtytwo patients undergoing partial or total lung resection for therapy of primary pulmonary carcinoma were included in this study. Immunohistochemical staining for CYP3A was performed with a modification of the ABC technique. Eight of the 32 cases of primary pulmonary carcinoma showed expression of CYP3A. In 12 of the 32 cases of normal tissue, the seromucous glands were positive for CYP3A. The bronchial epithelium was positive for CYP3A in 11 cases. We observed no correlation between CYP3A expression in tumour tissue and that in seromucous glands or bronchial epithelium. We conclude that CYP3A is present in both normal and cancerous lung tissue. Our findings suggest, however, no co-expression of CYP3A in lung cancer. 相似文献
82.
Klaus Kayser Sabine André Gerhard Böhm Sonia Donaldo-Jacinto Peter Fritz Herbert Kaltner Gian Kayser Wolf-Peter Kunze Andreas Nehrlich Fu-Yue Zeng Hans-Joachim Gabius 《Development genes and evolution》1995,204(5):344-349
Protein-carbohydrate interactions are supposed to play key roles in the mechanisms of cell adhesion, biosignalling and intracellular routing, warranting the analysis of the developmental course of expression of epitopes of this system. Thus, a panel of carrier-immobilized carbohydrate ligands was used as probes, namely lactose,N-acetylgalactosamine,N-acetylglucosamine, mannose, fucose and maltose. Additionally, an antibody to an endogenous -galactoside-binding lectin (anti-galectin-1), the biotinylated lectin and two further human lectins, namely the macrophage migration inhibitory factor-binding sarcolectin and serum amyloid P component (SAP) that displays selectivity for sulphated sugars and mannose-6-phosphate, were included. They enabled us to assess the extent of the presence of respective binding sites in fixed sections from human lungs (pulmonary epithelial cells), livers (hepatocytes) and hearts (myocard cells) of 10–50 weeks gestation. Invariably, specific binding was detected in the three organ types, at least in certain stages. In most of the cases, the intensity of staining exhibited developmental regulation. The apparent patterns reveal similarities between the different cell types, as seen with immobilizedN-acetylglucosamine as well as with labelled galectin-1 and sarcolectin. However, drastic differences among such patterns with nearly opposite developmental courses do also occur, as detected for carrier-attached mannose and maltose residues. These results point to a potential importance for the detected glycohistochemical features in human development and substantiate the possibility of differential regulation of the presence of binding sites for distinct sugars within a certain organ and between the individual cell types of the monitored organs. 相似文献
83.
The effect of monocular deprivation (covering one eye on the 11th posnatal day) and rearing in darkness (the animals were born, developed, and killed with total exclusion of light) on development of -adrenergic, serotoninergic, muscarinic cholinergic, glutamatergic, and benzodiazepine receptors in primary visual structures (visual cortex, lateral geniculate body, superior colliculus, and retina) was investigated in rats. For quantitative analysis of neurotransmitter receptors, the technique of ligand binding was used. It was shown that monocular deprivation affects the development of -adrenergic, serotoninergic, and glutaminergic receptors mainly in the lateral geniculate body and retina, whereas rearing in darkness affects mainly the development of serotoninergic receptors in the superior colliculus. The development of receptors of the cholinergic neurotransmitter system is disturbed only temporarily by visual deprivation. Changes found in receptor development after visual deprivation indicate altered activity of different neurotransmitter systems in corresponding visual structures.P. Flechsig Brain Research Institute, Leipzig, East Germany. Karl Marx University, Leipzig, East Germany. Translated from Neirofiziologiya, Vol. 16, No. 5, pp. 691–701, September–October, 1984. 相似文献
84.
The usefulness of hybridization by protoplast fusion and mitotic segregation for the genetic analysis of the imperfect fodder yeastCandida maltosa was tested. Mitotically stable fusion hybrids were obtained with frequencies between 10–6 and 10–7. Complementation tests were performed by protoplast fusion. Substances that are known to induce frequent mitotic segregation in other yeast species such as benomyl, p-fluorophenylalanine, and acriflavine were ineffective inC. maltosa. UV irradiation induced mitotic segregation in up to 10%. This agent induced mainly mitotic crossing over inC. maltosa. Our data enabled the construction of the linkage group I with the sequenceCEN-ade-26-pro-1. 相似文献
85.
H Schiessler K Ohlsson I Olsson M Arnhold Y Birk H Fritz 《Hoppe-Seyler's Zeitschrift für physiologische Chemie》1977,358(1):53-58
Inhibitors of animal, plant, and microbial origin were tested against human and canine granulocytic elastases. The trypsin-chymotrypsin inhibitors from dog submandibular glands, from soybeans (Bowman-Birk) and from chickpeas show strong interaction with these proteases (Ki = 10(-8) - 10(-9)M). The trypsin-kallikrein inactivator of bovine organs (Trasylol) is not active against granulocytic elastases or against human granulocytic cathepsin G. Elastatinal, a specific inhibitor of elastases, isolated from actinomycetes (Streptomyces griseoruber), forms stable complexes with elastase from human (Ki = 6.2 X 10(-6)M) and canine granulocytes (Ki = 1.1 X 10(-6)M). A possible therapeutic application of these inhibitors for the inactivation of granulocytic proteases, which are able to degrade connective tissue in different pathological states, is discussed. 相似文献
86.
Werner Nachtigall und Hans-Joachim Rothe 《Journal of Ornithology》1982,123(4):439-443
Zusammenfassung Bei Haustauben, die in einem horizontalen Windkanal mit 48 km/h stationär flogen, wurden mit Hilfe von Zeitlupenanalysen Schlagphasen nachgewiesen, die dem vonWeis-Fogh (1973) geforderten clap-and-fling Mechanismus entsprechen. Am Ende des Aufschlags schlagen die beiden Flügel mit der morphologischen Oberseite ± vollständig zusammen (clap). Vor dem Abschlag öffnen sie sich wie die Seiten eines Buches von vorn nach hinten (fling); erst am Ende dieser Phase entfernen sie sich voneinander. Weitere feinkinematische Ergebnisse werden mitgeteilt. Diese instationären Schlagphasen werden insbesondere dann eingesetzt, wenn hohe Luftkräfte benötigt werden. Die Kinematik der Flügelbewegung ist demnach so beschaffen, daß durch frühzeitige Zirkulationsinduzierung bereits ganz zu Beginn des Abschlags hohe Auftriebskräfte erzeugt werden könnten. Es wird diskutiert, daß der clap-and-fling Mechanismus auch für rasche Beschleunigungen bei hohem Schubbedarf eingesetzt werden könnte.
Mit Geräteunterstützung durch die Deutsche Forschungsgemeinschaft 相似文献
Evidence for a clap-and-fling mechanism in pigeons flying in a windtunnel
Summary Slow motion pictures of pigeons flying horizontally at a speed of 48 km/h in a windtunnel have shown flight patterns which seemed to be similar to the clap-and-fling mechanism discribed byWeis-Fogh (1973) for small insects. At the end of upstroke, both upper surfaces of the wings come together ± completely (clap). Before downstroke, the wings are opened like the pages of a book (fling). This instationary wingbeat pattern is used especially when high aerodynamic forces are needed. The clap-and-fling mechanism enables the bird to establish an early circulation so that, at the very beginning of downstroke, high lift forces can be produced. The question whether the clap-and-fling mechanism is also used for quick accelerations when greater thrust is required is also discussed.
Mit Geräteunterstützung durch die Deutsche Forschungsgemeinschaft 相似文献
87.
Abstract— Phenylalanine ammmonia-lyase (PAL), an enzyme which converts phenylalanine (Phe) and tyrosine (Tyr) to trans-p-cinnamic acid and trans-p-coumaric acid, respectively, was administered to mice and its effect on the conversion of [3H]tryptophan to 5-[3H]HT in the brain was measured. Although PAL significantly depleted plasma Tyr, it has little or no effect on either brain Tyr or catecholamine concentrations. Endogenous brain tryptophan levels were significantly increased 2 h after PAL administration, brain 5-HT was dramatically increased 4 h following PAL and each returned to baseline levels by 8 h. This return to baseline was accompanied by a marked decrease in the fraction of tryptophan converted to 5-HT during a 20 min pulse period preceding death, suggesting the activation of a compensatory decrease in 5-HT synthesis in response to increased 5-HT concentration. These data suggest that PAL administration readily produces reversible alterations in 5-HT synthesis and that this may be a fruitful approach to studying brain 5-HT function. 相似文献
88.
89.
Saint-Girons I. Fritz H. -J. Shaw C. Tillmann E. Starlinger P. 《Molecular genetics and genomics : MGG》1981,183(1):45-50
Molecular Genetics and Genomics - IS2 has been marked genetically by the in vitro insertion into its HindIII site of a 3.3 Kb HindIII fragment of Tn5 conferring resistance to kanamycin. The... 相似文献
90.