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991.
M. Daimon Eishirou Gojyou Makoto Sugawara Keiichi Yamatani Makoto Tominaga Hideo Sasaki 《Human genetics》1997,99(2):199-201
Hereditary coproporphyria (HCP) is an autosomal dominant disease characterized by a deficiency of coproporphyrinogen oxidase.
To date, four mutations of the gene have been reported. We report here another mutation in two Japanese families with HCP,
which was revealed by analysis of polymerase chain reaction (PCR)-amplified DNA fragments of the gene by a direct-sequencing
method. A point mutation, G to A, was found in exon 4 of the gene at position 538 of the cDNA from the reported putative translation
initiation codon ATG. This mutation results in a glycine to arginine substitution at amino acid 180. Two carriers in the family
were successfully diagnosed by detecting the mutation using restriction analysis of the PCR products.
Received: 23 April 1996 / Revised: 15 July 1996 相似文献
992.
H. Iwatsuki Kazunobu Sasaki Masumi Suda Chikako Itano 《Histochemistry and cell biology》1997,107(6):459-468
To clarify the origin of the central cells in hepatic erythroblastic islands, glycoconjugates on the surface of cellular
constituents in fetal mice liver were ultrahistochemically examined using lectin staining. At 11 days of gestation, the cells
derived from mesenchyme in fetal liver, including sinusoidal macrophages, endothelial cells, and erythropoietic cells, bound
Griffonia simplicifolia isoagglutinin I-B4 (GS-I-B4), but hepatocytes lacked binding sites for the isolectin. Scavenger macrophages in the hepatic
cords at 13 days of gestation and the central cells in the erythroblastic islands at 15 days of gestation also bound GS-I-B4.
Hepatocytes, however, exhibited no GS-I-B4 binding site at any gestational day. At 11 days of gestation, none of the cells
in fetal liver had binding sites for soybean agglutinin (SBA), but cells derived from mesenchyme acquired these binding sites
at 13 days of gestation. The central cells in the erythroblastic islands also bound SBA, but hepatocytes did not bind the
lectin at all. The central cells in the erythroblastic islands can be considered to belong to a mesenchymal cell lineage,
and primitive sinusoidal macrophages at 11 days of gestation are possible precursors of these central cells.
Accepted: 22 January 1997 相似文献
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996.
Role of transpiration from fruits in phloem transport and fruit growth in tomato fruits 总被引:1,自引:0,他引:1
Sink activity of fruits had been suggested to vary depending on transpiration of fruits. In this study, the effect of transpiration on dry matter accumulation was evaluated in tomato ( Lycopersicon esculentum Mill.). Fruits of cv. Saturn at 14 days after anthesis were enclosed in chambers and aerated with dried (<15% RH) or moistened (>90% RH) air. These treatments did not cause any significant differences in fruit fresh weight, dry weight, percentage of dry matter, and concentration of soluble sugars within 5 days of the treatment, or the import of 14 C within 18 h after the application of 14 CO2 to the source leaves. However, displacement transducer measurement of each fruit showed a 40% reduction in growth rate in response to exchange of moistened air with dried air. When fruits of cv. Momotaro were exposed to transpiration treatments from the beginning of visible fruit enlargement until the ripening stage, the fruits exhibited 20% reduction in growth and lower accumulation of dry matter at harvest following treatment with dried air. These results suggested that higher transpiration reduced both water accumulation and dry matter accumulation. In contrast, when fruit growth was mechanically restricted by enclosing the fruits in a chamber packed with glass beads, and dried or moistened air was passed through the spaces between the glass beads, fruits exhibited higher dry matter accumulation under dried air treatment conditions. The results show that only under artificial conditions would transpiration of fruits potentially drive carbohydrate transport; it does not serve as a limiting step of carbohydrate transport to tomato fruits under normal circumstances. 相似文献
997.
Hattan Jun-ichiro Shindo Kazutoshi Ito Tomoko Shibuya Yurica Watanabe Arisa Tagaki Chie Ohno Fumina Sasaki Tetsuya Ishii Jun Kondo Akihiko Misawa Norihiko 《Planta》2016,243(4):959-972
Planta - A novel terpene synthase ( Tps ) gene isolated from Camellia brevistyla was identified as hedycaryol synthase, which was shown to be expressed specifically in flowers. Camellia plants are... 相似文献
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Hiroshi Yokoyama Ayako Sasaki Tadashi Yoshizawa Hiroshi Kijima Kenichi Hakamada Katsuya Yamada 《Human cell》2016,29(3):111-121
Extrahepatic bile duct cancer (cholangiocarcinoma) has a poor prognosis. Since surgical resection is the only way to prolong the patient’s life, it is of critical importance to correctly determine the extent of lesions. However, conventional pre-operative assessments have insufficient spatial resolution for determining the surgical margin. A fluorescent contrast agent might provide a more precise measure to identify anomalies in biliary surface, when combined with probe-based confocal laser endomicroscopy (pCLE). We have previously shown that 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-l-glucose (2-NBDLG), a fluorescent derivative of l-glucose (fLG), is specifically taken up into spheroids consisting of cells showing heterogeneous nuclear-cytoplasm ratio, a feature of malignant cells in clinical settings. In addition, a combined use of 2-TRLG, a membrane-impermeable fLG, with 2-NBDLG visualized membrane integrity as well. We therefore explored in the present study the availability of the fLGs in vivo as a contrast agent for pCLE by using a hamster model of cholangiocarcinoma. Extrahepatic cholangiocarcinoma developed in mid common duct in ~20 % of the animals subjected to cholecystoduodenostomy with the ligation at the distal end of the common duct followed by injection of a carcinogen N-nitrosobis(2-oxopropyl)amine. After infusing bile duct with a solution containing 2-NBDLG and 2-TRLG, the lumen was surgically exposed and examined by pCLE. Fluorescence pattern characterized by bright spots and dark clumps was detected in the areas diagnosed with cholangiocarcinoma in later histopathology, whereas no such pattern was detected in control animals. These findings may form a basis for elucidating a potential availability of fLGs in imaging cholangiocarcinoma by pCLE. 相似文献
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