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971.
A Chloroplastic UDP-Glucose Pyrophosphorylase from Arabidopsis Is the Committed Enzyme for the First Step of Sulfolipid Biosynthesis 总被引:1,自引:0,他引:1
972.
Yoshioka M Sagara H Takahashi F Harada N Nishio K Mori A Ushio H Shimizu K Okada T Ota M Ito YM Nagashima O Atsuta R Suzuki T Fukuda T Fukuchi Y Takahashi K 《American journal of physiology. Lung cellular and molecular physiology》2009,296(1):L30-L36
Multidrug resistance-associated protein 1 (MRP1) is a cysteinyl leukotriene (CysLT) export pump expressed on mast cells. CysLTs are crucial mediators in allergic airway disease. However, biological significance of MRP1 in allergic airway inflammation has not yet been elucidated. In this study, we sensitized wild-type control mice (mrp1(+/+)) and MRP1-deficient mice (mrp1(-/-)) to ovalbumin (OVA) and challenged them with OVA by aerosol. Airway inflammation and goblet cell hyperplasia after OVA exposure were reduced in mrp1(-/-) mice compared with mrp1(+/+) mice. Furthermore, CysLT levels in bronchoalveolar lavage fluid (BALF) from OVA-exposed mrp1(-/-) mice were significantly lower than those from OVA-exposed mrp1(+/+) mice. Levels of OVA-specific IgE, IL-4, and IL-13 in BALF were also decreased in OVA-exposed mrp1(-/-) mice. IgE-mediated release of CysLTs from murine bone marrow-derived mast cells was markedly impaired by MRP1 deficiency. Our results indicate that MRP1 plays an important role in the development of allergic airway inflammation through regulation of IgE-mediated CysLT export from mast cells. 相似文献
973.
Hironori Adachi Tatsuya Kondo Rei Ogawa Norio Ishii Keishi Miyata Hiroyuki Motoshima Kaku Tsuruzoe Motohiro Takeya Gou Young Koh Toshio Suda Eiichi Araki 《Biochemical and biophysical research communications》2009,379(4):806-355
Angiopoietin-like protein family 4 (Angptl 4) has been shown to regulate lipoprotein metabolism through the inhibition of lipoprotein lipase (LPL). We generated ApoE−/−Angptl 4−/− mice to study the effect of Angptl 4 deficiency on lipid metabolism and atherosclerosis. Fasting and postolive oil-loaded triglyceride (TG) levels were largely decreased in ApoE−/−Angptl 4−/− mice compared with and ApoE−/−Angptl 4+/+ mice. There was a significant (75 ± 12%) reduction in atherosclerotic lesion size in ApoE−/−Angptl 4−/− mice compared with ApoE−/− Angptl 4+/+ mice. Peritoneal macrophages, isolated from Angptl 4−/− mice to investigate the foam cell formation, showed a significant decrease in newly synthesized cholesteryl ester (CE) accumulation induced by acetyl low-density lipoprotein (acLDL) compared with those from Angptl 4+/+ mice. Thus, genetic knockout of Angptl 4 protects ApoE−/− mice against development and progression of atherosclerosis and strongly suppresses the ability of the macrophages to become foam cells in vitro. 相似文献
974.
Yokozawa Y Tamai H Tatewaki S Tajima T Tsuchiya T Kanzawa N 《Journal of biochemistry》2002,132(5):751-758
We have cloned four cDNAs encoding astacin-like squid metalloproteases (ALSMs)-I and -II from the Japanese common squid and ALSMs-I and -III from the spear squid. Analysis of the deduced amino acid sequences revealed that ALSMs possess a signal peptide and a pro-sequence followed by an astacin-like catalytic domain and an MAM (meprin, A5 protein, receptor protein-tyrosine phosphatase mu) domain. Phylogenetic analysis revealed that ALSM corresponds to a new cluster of astacins. To analyze the function of the MAM domain, wild-type ALSM and an MAM-truncated mutant were expressed in a baculovirus expression system. The expressed protein encoding full-length ALSM hydrolyzed myosin heavy chain as effectively as native ALSM, whereas the MAM-truncated mutant possessed no protease activity, suggesting that the MAM domain contributes to substrate recognition. ALSM has been isolated from squid liver and mantle muscle. However, analysis with a specific antibody generated against ALSM indicated the presence of ALSM in a wide variety of tissues. ALSM was located in the extracellular matrix of mantle muscle cells. Thus, ALSM is a secreted protease, as are other members of the astacin family. The extracellular localization raises the possibility of substrates other than myosin. The physiological role of ALSM remains unknown, at this time. 相似文献
975.
Masashi Shimizu Natsuki Kosaka Takashi Shimada Takemitsu Nagahata Hironori Iwasaki Hisaki Nagai Tadayoshi Shiba Mitsuru Emi 《DNA research》2002,9(5):173-178
We have devised a novel method for automated microsatellite analysis using "universal" fluorescent labeling. This system is based on polymerase chain reactions driven by sequence-specific primers and a reporter primer labeled with a fluorescent dye at its 5' end. The forward sequence-specific primer is designed with a tag region bearing no homology to any human genomic sequence. Complementary tag sequences act as templates for the 6-carboxyfluorescein-labeled reporter primer, and those products can be analyzed with an autosequencer. The results we achieved with this assay system were consistent with the results of conventional assays using radioisotope-labeled primers, and diagnosis required less time. Furthermore, the fluorescent-labeled reporter primer is "universal" in that it can be used with different sequence-specific primers designed to carry the appropriate tag sequence at their 5'-ends. Our observations suggest that the "universal" fluorescent labeling method is an efficient tool for analyzing sequence variations in human DNA. 相似文献
976.
Purification and properties of an aminopeptidase from the mid-gut gland of scallop (Patinopecten yessoensis) 总被引:1,自引:0,他引:1
Umetsu H Arai M Ota T Kudo R Sugiura H Ishiyama H Sasaki K 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2003,136(4):935-942
An aminopeptidase was isolated from the mid-gut gland of Patinopecten yessoensis. The enzyme was purified from an acetone-dried preparation by extracting, ammonium sulfate precipitation, Hi-Load Q column chromatography, isoelectric focusing, and POROS HP2 and HQ column chromatography. The molecular weight of the enzyme was estimated to be 61 kDa by SDS-polyacrylamide gel electrophoresis and 59 kDa by gel permeation chromatography. The isoelectric point of the enzyme was 5.2 and the optimum pH was 7.0 toward leucine p-nitroanilide (Leu-pNA). The enzyme was inhibited by o-phenanthroline. The activity of the enzyme treated with o-phenanthroline was completely recovered by adding excess Zn2+. Relative hydrolysis rates of amino acid-pNAs and amino acid-4-methylcoumaryl-7-amides (amino acid-MCAs) indicated that the enzyme preferred substrates having Ala or Met as an amino acid residue. The enzyme had a Km of 32.2 μM and kcat of 29.5 s−1 with Ala-pNA and a Km of 11.1 μM and kcat of 9.49 s−1 with Ala-MCA. The enzyme sequentially liberated amino acids from the amino-termini of Ala–Phe–Tyr–Glu. 相似文献
977.
978.
Fauziah Ma’ruf Ilma Sasaki Yuka Kerbs Anastasia Nießer Jochen Sato Yu Taniguchi Hironori Okano Kenji Kitani Shigeru Restiawaty Elvi Akhmaloka Honda Kohsuke 《Extremophiles : life under extreme conditions》2021,25(4):393-402
Extremophiles - Serine hydroxymethyltransferase (SHMT) and threonine aldolase are classified as fold type I pyridoxal-5’-phosphate-dependent enzymes and engaged in glycine biosynthesis from... 相似文献
979.
Differential development of rabbit embryos following microinsemination with sperm and spermatids 总被引:1,自引:0,他引:1
Ogonuki N Inoue K Miki H Mochida K Hatori M Okada H Takeiri S Shimozawa N Nagashima H Sankai T Ogura A 《Molecular reproduction and development》2005,72(3):411-417
Microinsemination is the technique of delivering male germ cells directly into oocytes. The efficiency of fertilization after microinsemination and subsequent embryo development may vary with the animal species and male germ cells used. The present study was undertaken to observe the in vitro and in vivo developmental ability of rabbit embryos following microinsemination with male germ cells at different stages. First, we assessed their oocyte-activating capacity by injecting them into mouse and rabbit oocytes. The majority of mouse oocytes were activated irrespective of the type of rabbit male germ cell injected (61-77%), whereas rabbit oocytes were activated differently according to the type of male germ cells (89%, 75%, and 29% were activated by spermatozoa, elongated spermatids, and round spermatids, respectively; P < 0.05). After 120 hr in culture, 66%, 45%, and 13%, respectively, of these activated rabbit oocytes (pronuclear eggs) developed into blastocysts (P < 0.05). Additional electric pulse stimulation of round spermatid-injected oocytes increased the blastocyst rate to 43%. After 24 hr in culture, some four to eight cell embryos were transferred into the oviducts of pseudopregnant females. Normal pups were born from spermatozoa and elongated spermatids, but not from round spermatids. Karyotypic analysis at the morula/blastocyst stage revealed that the majority of round spermatid-derived embryos had abnormal ploidy (8 out of 12 embryos). Our study indicates that rabbit male germ cells acquire the ability to activate oocytes and to support subsequent embryo development as they undergo spermiogenesis. As these differential developmental patterns are similar to those reported for humans in vitro and in vivo, rabbits may provide an alternative small animal model for studying the biological nature and molecular basis of human microinsemination techniques, especially those using immature male germ cells. 相似文献
980.
Kanzawa N Tatewaki S Watanabe R Kunihisa I Iwahashi H Nakamura K Tsuchiya T 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2005,142(2):153-163
Astacin metalloprotease family members function in a wide variety of biologic events, including cell differentiation and morphogenesis during embryonic development and adult tissue differentiation. We previously isolated and characterized an astacin-like squid metalloprotease (ALSM). To elucidate the embryonic expression of ALSM, we performed immunohistochemical analysis with specific antibodies and examined the expression profiles of ALSM isoforms by in situ hybridization analysis. Tissue distribution and expression were also examined in adult spear squid. mRNA expression of ALSM isoforms I and III was first detected in newly hatched squid and was restricted to the liver. No mRNA signals were detected in other tissues even in adult squids. At the protein level, both isoforms were prominent in the liver of embryos and later in digestive organs of adult squid. Both isoforms were also detected in muscle tissues, including mantle and tentacle muscle. Staining for ALSM III was also identified in the iris and in tissues near the eye in squid embryos. However, no reactive bands were detected by immunoblotting of adult squid eyes. Thus, ALSM is initially expressed at the late stage of embryogenesis in spear squid, and expression is restricted to the liver. Thereafter, ALSM isoforms function in various tissues in an isoform-dependent manner. 相似文献