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991.
A new zoarcid,lycenchelys aurantiaca, from the pacific coast off northern japan (teleostei: Perciformes) 总被引:1,自引:1,他引:0
A new zoarcid fish,Lycenchelys aurantiaca, is described on the basis of 10 specimens (86.3–135.8 mm SL) from depths of 500–700 m along the Pacific coast of northern
Honshu, Japan. Although this species resemblesLycenchelys alta andL. squamosa in having a smaller number of vertebrae (85–88) and a rather short body, it is distinguished from them by the following characters:
pectoral fin rays 13–16; preoperculomandibular pores 7 (4 mandibular pores+3 preopercular pores); reddish yellow body. 相似文献
992.
Hidetoshi Arakawa Shuji Nakashiro Akio Tsuji Masako Maeda 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1998,716(1-2)
We describe the development of a sensitive high-performance liquid chromatographic (HPLC) method for polymerase chain reaction (PCR) products using bisbenzimide (Hoechst 33258 dye) based fluorimetric detection. The detection limit and specificity for double-strand DNA detection are improved in comparison with HPLC with UV absorbance detection. This HPLC, using a column packed with diethylaminoethyl-bonded non-porous resin particles, was applied to the detection of allele-specific PCR and restriction fragment length polymorphism analysis. We also developed a hybridization method analyzed by HPLC. DNA fragments (149 bp) containing the mutation site (C→A,G,T) in the N-ras gene were amplified by PCR. Fluorescein isothiocyanate (FITC)-labeled DNA probes were also prepared by PCR using FITC-labeled 5′ primer. Analysis of mutation was performed by the separation of a hybrid and non-reactive DNA probe with HPLC with fluorimetric detection after the hybridization of target DNA (149 bp) and a FITC DNA probe. The effects of various factors on hybridization were examined to establish optimal assay conditions. Under the conditions determined, a point mutation in PCR products obtained from the N-ras gene could be detected specifically by this method. The analysis of PCR products by HPLC may potentially be useful for DNA diagnosis. 相似文献
993.
Hitoshi Takami Nobuyuki Kishibayashi Akio Ishii Toshiaki Kumazawa 《Bioorganic & medicinal chemistry》1998,6(12):2441-2448
A novel series of indole and benzimidazole derivatives were synthesized and evaluated for their inhibitory activity of rat prostatic 5α-reductase. Among these compounds, 4-{2-[1-(4,4′-dipropylbenzhydryl)indole-5-carboxamido]phenoxy}butyric acid (15) and its benzimidazole analogue 25 showed potent inhibitory activities for rat prostatic 5α-reductase (IC50 values of 9.6 ± 1.0 and 13 ± 1.5nM, respectively), with the potency very close to that of finasteride. Compound 30, in which the moiety between the benzene ring and amide bond was replaced by quinolin-4-one ring, showed almost equipotent activity (IC50 = 19 ± 6.2nM) with the correspondent amide derivative 13. This result was consistent with the previous observation that the coplanarity of this moiety might contribute to the potent inhibitory activity. 相似文献
994.
Kazuya Matsuura Yasuo Bunai Isao Ohya Akira Hara Masayuki Nakanishi Hideo Sawada 《The Histochemical journal》1994,26(4):311-316
Summary The immunocytochemical localization of tetrameric carbonyl reductase in the mouse lung was determined by an electron-microscopical immunogold procedure using monospecific antibodies against the enzyme. The labelling of carbonyl reductase was observed within the mitochondria of the ciliated and non-ciliated cells of the bronchioles and the type II alveolar pneumocytes, and the density of labelling in the non-ciliated cells was higher than those in the other cells. No significant labelling was detected over other compartments of the epithelial cells. The labelling was undetectable in the type I alveolar cells, alveolar macrophages and connective tissue cells of the lung. These results clearly indicate the localization of carbonyl reductase to the mitochondrial matrix of these epithelial cells, of which the non-ciliated bronchiolar cells contained particularly high amounts of the enzyme. 相似文献
995.
996.
Masayuki Kamochi Masanori Ogata Shin-ichi Yoshida Takahiro Matsumoto Etsuji Kubota Yasuo Mizuguchi Akio Shigematsu 《FEMS immunology and medical microbiology》1993,7(2):153-159
Abstract Proteose peptone-induced murine peritoneal macrophages (Mø) were preincubated with 100–800 μg/ml of dextran sulphate (DS) 500 ( M r 500 000) or DS1000 ( M r 1 000 000). After 2–24 h of the preincubation, the Mø were stimulated with 1 μg/ml of lipopolysaccharide (LPS) in vitro for 18 h in DS-free culture medium. The culture supernatants were then collected for TNF assay. The LPS-induced TNF activity of Mø supernatant preincubated with DS500 or DS1000 for 6 h was enhanced by up to about ten-fold compared with those preincubated without DS. This enhancing effect was not observed when Mø were preincubated with 100–800 μg/ml of low molecular weight DS5 ( M r 5000) or neutral dextran (Dex) 500 ( M r 500 000). The enhancement of LPS-induced TNF-α production from Mø was observed after 2 or 4 h of incubation with DS1000 or DS500, respectively. The phagocytic activity of Mø was determined in vitro by the ingestion index and phagocytic capacity using Saccharomyces cerevisiae . Treatment with DS500 or DS1000 significantly suppressed the phagocytic activity from 2 h after the incubation, but this suppression was not observed in Mø incubated with DS5 or Dex500. Our experiments indicate that DS500 and DS1000 act directly on Mø and enhance LPS-induced TNF-α production from Mø, and that the enhancement is closely related to the suppression of Mø phagocytic function. 相似文献
997.
Using the monoclonal antibody (MoAb) Xa5B6 as probe, the authors examined the mechanisms of cytoplasmic rearrangement occurring
during maturation of theXenopus oocyte. The antigen molecules recognized by the MoAb are arranged in radial striations of the oocyte cytoplasm. The radial
striations were disorganized in vitro by progesterone treatment, and the antigen molecules were uniformly distributed, predominantly
in the animal hemisphere. Even when the germinal vesicle was mechanically removed or when germinal vesicle breakdown was suppressed
in a K+-free medium, progesterone induced a disorganization of the radial striations. This progesterone-induced disorganization was
inhibited by the protein synthesis inhibitor cycloheximide. When full-sized oocytes were treated with cytochalasin B, the
radial striations were also disorganized, but the antigen molecules did not disperse into the large mass. Colchicine treatment
had little effect. Antigen molecules were no longer arranged in radial striations and were completely dispersed when the oocyte
was simultaneously treated with both drugs. These results indicate that the two compartments in the oocyte cytoplasm, the
yolk-free cytoplasm and yolk column, are organized by different types of cytoskeletal system. It is also suggested that the
maturation-promoting factor (MPF) activated during progesterone-induced maturation disrupts these cytoskeletal systems and
disorganizes the radial striations.
Correspondence to: A.S. Suzuki 相似文献
998.
Hydrostatic pressure is like high temperature and oxidative stress in the damage it causes to yeast 总被引:3,自引:0,他引:3
Hitoshi Iwahashi Sinsuke Fujii Kaoru Obuchi Sunil C. Kaul Akio Sato Yasuhiko Komatsu 《FEMS microbiology letters》1993,108(1):53-57
Abstract A comparison of barotolerance, thermotolerance and oxygen tolerance was made under different physiological conditions, such as heat shocked and recovered state, different growth phases and changes of physiological conditions by mutations. The three kinds of tolerance showed similar features under different physiological conditions. We suggest that the damage caused by hydrostatic pressure may be essentially the same as that due to high temperature and oxidative stress in yeast. 相似文献
999.
Fumito Matsuura Masaya Ohta Khoichi Murakami Yujirou Matsuki 《Glycoconjugate journal》1993,10(3):202-213
Structures of the Asn linked oligosaccharides of quail egg-yolk immunoglobulin (IgY) were determined in this study. Asn linked oligosaccharides were cleaved from IgY by hydrazinolysis and labelled withp-aminobenzoic acid ethyl ester (ABEE) afterN-acetylation. The ABEE labelled oligosaccharides were then fractionated by a combination of Concanavalin A-agarose column chromatography and anion exchange, normal phase and reversed phase HPLC before their structures were determined by sequential exoglycosidase digestion, methylation analysis, HPLC, and 500 MHz1H-NMR spectroscopy. Quail IgY contained only neutral oligosaccharides of the following categories: the glucosylated oligomannose type (0.6%, Glc1-3Glc1-3Man9GlcNAc2; 35.6%, Glc1-3Man7–9GlcNAc2). oligomannose type (15.0%, with the structure Man5–9GlcNAc2) and biantennary complex type with core structures of-Man1-3(-Man1-6)Man1-4GlcNAc1-4GlcNAc (9.9%),-Man1-3(GlcNAc1-4)(-Man1-6)Man1-4GlcNAc1-4GlcNAc (25.1%) and-Man1-3(GlcNAc1-4)(-Man1-6)Man1-4GlcNAc1-4(Fuc1-6)GlcNAc (11.4%). Although never found in mammalian proteins, glucosylated oligosaccharides (Glc1Man7–9GlcNAc2) have been located previously in hen IgY.Abbreviations IgG, IgM, IgA, IgY
immunoglobulin G, M, A and Y, respectively
- ABEE
p-aminobenzoic acid ethyl ester 相似文献
1000.
The effect of the Cyt b6-f redox state on the PSI formationwas examined with the cyanophyte Synechocystis PCC 6714 by usinga Q-cycle inhibitor, HQNO (2-n-heptyl-4-hydroxyquinoline N-oxide).HQNO inhibited the rapid reduction of flash-oxidized Cyt f,the reaction correlating with the stimulation of PSI formation,on one hand, and accumulated reduced Cyt b6, on the other, indicatingthat the electron flow in the Q-cycle correlates with regulationof PSI synthesis. HQNO also inhibited the stimulation of PSIformation under PSII light, resulting in a low PSI/PSII ratioeven under PSII light, while the PSI formation under PSI lightwas not suppressed by HQNO. Simultaneous inhibition of Cyt b6oxidation through the Q-cycle and the stimulated PSI formationby HQNO suggests that an HQNO-sensitive Cyt b6 oxidation isinvolved in the mechanism of monitoring the state of electrontransport system for regulation of PSI formation. (Received March 3, 1993; Accepted August 9, 1993) 相似文献