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31.
A Pekki T Joensuu K Vidqvist D Toft P Tuohimaa 《Journal of steroid biochemistry》1989,34(1-6):351-354
A semiquantitative immunohistochemical technique was developed for identification of chick progesterone receptor (PR). The mouse monoclonal antibody PR6 was used. The nuclear PR concentration was analyzed with Leitz Orthoplan MPV-3 light microscope. The target tissue was chick oviduct, with epithelial, glandular, mesenchymal, smooth muscle and peritoneal cells analyzed separately. PR concentration varied between different cell types and also from cell to cell within a single cell type. A significant decrease of PR concentration, as noted by decrease in staining, was also observed in all studied cell types, 6 h after a single injection of progesterone. This technique allows for histological identification of biochemical events that should help lead to the understanding of the role of PR changes in a variety of experimental situations. 相似文献
32.
Morphological and hybridization studies were carried out in H. pubiflorum s. 1. (2n= 14). Chromosome pairing observed at MI in the hybrids was high, but indications of weak sterility barriers were observed. It is concluded that (i) hybridization is fairly easy to perform, and the populations studied belong to the same species, (ii) no divergence in the ssp. halophilum genome was observed, except in (iii) a population with at least one reciprocal translocation, (iv) the halophilum × breviaristatum hybrids had lowered pairing with an increased frequency of univalents, (v) the pairing combined with morphology suggest recognition of H. pubiflorum ssp. breviaristatum (Parodi & Nicora) C. Baden (comb. nov.). 相似文献
33.
Kirsty Barr Henrik Moller Emma Christmas Philip Lyver Jacqueline Beggs 《Oecologia》1996,105(2):266-270
An introduced social wasp Vespula vulgaris may compete with native birds for honeydew and invertebrates in New Zealand forests. Experimentally hidden mealworms (Tenebrio molitor) persisted longer at two sites following wasp poisoning that at two sites where wasps were not poisoned. Mealworms persisted longer in the morning than in the afternoon within all study sites. An unusually low mealworm removal rate during a morning trial before wasp poisoning heavily influences the results of this experiment but we have no ecological reason to ignore it. Wasps may therefore be having a heavy impact on invertebrate abundance on very short time scales (within a day following dawn emergence). They may also remove cached food items that would otherwise be retrieved by the South Island robin (Petroica australis australis) during cold or dark feeding conditions. 相似文献
34.
Thurnher Martin; Wagner Ernst; Clausen Henrik; Mechtler Karl; Rusconi Sandro; Dinter Andre; Birnstiel Max L.; Berger Eric G.; Cotten Matt 《Glycobiology》1994,4(4):429-435
The mucin-type carbohydrate Tn cryptantigen (GalNAc1-O-Ser/Thr,where GalNAc is N-acetyl-D-galactosamine) is expressed in manycarcinomas, in haemopoietic disorders including the Tn syndrome,and on human immunodeficiency virus (HIV) coat glycoproteins,but is not expressed on normal, differentiated cells becauseof the expression of a Tn-processing galactosyltransferase.Using Jurkat T leukaemic cells which express high levels ofTn antigen due to deficient Tn galactosylation, we have establishedthe Tn antigen-mediated gene transfer and demonstrate the considerableefficiency of this approach. We used poly(L-lysine) conjugatesof the monoclonal antibody 1E3 directed against the Tn antigento deliver the luciferase and ß-galactosidase reportergenes to Jurkat cells by receptor-mediated endocytosis. Additionof unconjugated 1E3 reduced transfection efficiency in a concentration-dependentmanner and incubation with free GalNAc abolished DNA transfercompletely, indicating that gene delivery is indeed mediatedby the Tn antigen. Pre-treatment of Jurkat cells with Vibriocholerae sialidase, which uncovers additional Tn antigens, resultedin an improvement of gene transfection. Both human and chickenadenovirus particles attached to the DNA/polylysine complexstrongly augmented transgene expression. When the ß-galactosidase(lacZ) gene was delivered to Jurkat cells by Tn-mediated endocytosis,up to 60% of the cells were positive in the cytochemical stainusing 5-bromo-4-chloro-3-indolyl-ß-D-galactopyranoside(X-gal) as a chromogenic substrate. The efficiency of the transferrinreceptor-mediated DNA uptake into Jurkat cells was comparativelylow, although these cells were shown to express considerableamounts of transferrin receptor. We show here that a mucin-typecarbohydrate antigen mediates highly efficient DNA uptake byendocytosis into Jurkat T cells. This method represents a 50-foldimprovement of Jurkat cell transfection efficiency over otherphysical gene transfer techniques. Specific gene delivery toprimary cancer cells exhibiting Tn epitopes may especially bedesirable in immunotherapy protocols. adenovirus endocytosis gene transfer T cell Tn antigen 相似文献
35.
Henrik Skovgård Jonna Tomkiewicz Gösta Nachman Mikael Münster-Swendsen 《Experimental & applied acarology》1993,17(1-2):41-58
The effect of the cassava green mite Mononychellus tanajoa on the growth and yield of cassava Manihot esculenta was studied over a 10-month period in two field trials near Lake Victoria in Kenya. One plot was maintained free of mites by means of acaricide, while the other was artificially infested.The highest population density of M. tanajoa occurred during the dry season. A maximum leaf area index (LAI) of about 2 was reached at the onset of the dry season. The total leaf area of mite infested plants was reduced compared with uninfested plants during the dry spell. During the following rainy season infested plants recovered and attained the same leaf area as uninfested plants. A multiple regression model predicting the leaf area showed that 58% of the seasonal variation could be explained by plant age, soil water, and leaf injury.The net growth rate of infested plants was lower than that of uninfested plants. Maximum values of 21 (infested plants) and 49 (uninfested plants) g m-2 week-1 were attained at the onset of the second rainy season. No difference was found between uninfested and infested plants with respect to net assimilation rates per unit leaf area during the dry season. The net assimilation rates reached a maximum almost at the same time as the growth rates, but the infested plants peaked slightly earlier and at a lower level than the uninfested plants.
M. tanajoa did not affect the relative allocation of dry matter into stems and storage roots, but the absolute allocation of dry matter declined with increasing mite injury. Thus, after 10 months the dry matter of infested plants was reduced by 29% and 21% for storage roots and stems, respectively, compared with the uninfested plants. 相似文献
36.
Uwe Karsten Gisela Papsdorf Annedore Pauly Borivoj Vojtesek Roland Moll E. Birgitte Lane Henrik Clausen Peter Stosiek Michael Kasper 《Differentiation; research in biological diversity》1993,54(1):55-66
Abstract. Normal (non-transformed) human mammary epithelial cell lines derived from reduction mammoplasties were analyzed by immunocytochemistry with more than 80 monoclonal antibodies (mAbs) and other specific reagents to tissue-specific and developmentally regulated antigens at different passage levels. A subpopulation of poorly differentiated, proliferating epithelial cells, corresponding to the 'selected' cell type of late passages, is shown to be characterized by a new marker, the histo-blood group antigen H type 2, probably carried on a membrane-bound glycolipid. These cells also express a number of other onco-developmental carbohydrate antigens [Ley , Lex , sialosyl-Lea , precursor of Thomsen Friedenreich antigen (Tn ), but not Thomsen-Friedenreich antigen and sialosyl-Tn ]. Their cytokeratin (CK) phenotype, as assessed by reactivity with monospecific mAbs and two-dimensional gel electrophoresis, is CK 5, 6, 14 and 17, with CK 19 being consistently absent, and varying minor amounts of CK 7, 8 and 18, as well as 15 and 16. The reactivity of these cells with a panel of 11 mAbs specific for CK 18 varies considerably even after cloning, indicating heterogeneity of epitope expression or accessibility. Our data strongly suggest that the H type 2+ cells develop from the basal cell layer of the mammary gland. 相似文献
37.
Terje H. Larsen Henrik S. Huitfeldt Ole Myking Thorvald Sætersdal 《Cell and tissue research》1993,272(2):201-210
A close spatial relationship between specific granules containing atrial natriuretic factor (ANF) and microtubules was demonstrated in primary cultures of neonatal rat cardiac myocytes. For the detection of specific granules and microtubules, the myocytes were double immunolabelled with antibodies against -ANF and -tubulin and examined by conventional fluorescence or laser scanning confocal microscopy. In addition, the ultrastructural distribution of specific granules was demonstrated by electron microscopy. In the atrial myocytes, ANF was stored in numerous specific granules that were mainly localized in the perinuclear sarcoplasm. In the ventricular myocytes, however, a minority of the cells (10%) exhibited limited ANF immunoreactivity after 4 days in culture. Microtubules were present throughout the sarcoplasm of the myocytes. They were most densely packed in the perinuclear regions. Depolymerization of the microtubules with nocodazole was followed by dispersal of ANF immunostaining both in the atrial myocytes and in the ventricular myocytes exhibiting ANF immunoreactivity. When the microtubules were allowed to recover, the perinuclear distribution of specific granules, as seen in non-treated myocytes, reappeared. Measurements of secreted immunoreactive ANF by radioimmunoassay revealed that the secretion of ANF from atrial myocytes into the medium was significantly reduced following nocodazole treatment, whereas a similar decrease in secretion from ventricular myocytes was not observed. These findings indicate that ANF-containing specific granules are closely associated with microtubules within the myocytes. It is suggested that secretion of ANF from the atrial myocytes, in contrast to the ventricular myocytes, is microtubule-dependent. 相似文献
38.
Henrik Printz 《Archives of microbiology》1962,42(1):64-73
Zusammenfassung Die Natur der konzentrischen Zonen in den Stämmen von Laminarien ist lange Zeit umstritten gewesen. Nachdem aber im Jahre 1926 nachgewiesen wurde, daß das gesamte vegetative Wachstum bei den nordischen, regelmäßig blatterneuernden Laminarien periodisch und synchron in allen Teilen der Pflanzen erfolgt, war damit bewiesen, daß diese Zonen wirkliche Jahresringe darstellen, die im Zusammenhang mit dem jährlichen Blattwechsel stehen.Ebenso wie die Dendrochronologie die Jahresringe der Bäume als Grundlage für forstliche Untersuchungen über Bestockung, Alter, Produktions- und Verjüngungsverhältnisse im Waldbau benutzt, kann man aus den Jahresringen der nordischen Laminarien entsprechende Rückschlüsse ziehen.Bei der stetig steigenden Nutzbarmachung und Verwendung der Meeresalgen sind derartige Gesichtspunkte von aktuellem Interesse in der Algologie geworden.Vorliegende Arbeit ist ein Versuch, eine Bestandsanalyse in phykochronologischer Regie durchzuführen mit besonderer Berücksichtigung etwaiger Schwankungen in Assoziationen von Laminaria digitata f. stenophylla hinsichtlich Repopulation, Bestockung, Wachstumsverhältnissen und anderer damit verknüpfter biologischer Fragen.Die Untersuchung wurde in den Jahren 1955–1958 an der norwegischen Westküste vorgenommen.Es sei darauf hingewiesen, daß sowohl das vegetative Wachstum als auch die Repopulation bei der genannten Alge von Jahr zu Jahr innerhalb ausgedehnten Grenzen variieren kann und daß diese Pflanze eine nur kurze Lebensdauer hat. Exemplare von mehr als 6 Jahren wurde nicht angetroffen. Ihr Bestand wird deshalb recht rasch erneuert.Professor Dr. E. G. Pringsheim zum 80. Geburtstag gewidmet. 相似文献
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