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Takagi M Motohashi K Izumikawa M Khan ST Hwang JH Shin-Ya K 《Bioscience, biotechnology, and biochemistry》2010,74(11):2355-2357
In the course of our chemical screening program for new secondary metabolites, we isolated a new compound JBIR-66 (1) from the culture broth of the tunicate-derived actinomycete, Saccharopolyspora sp. SS081219JE-28. The structure of 1 was determined to be (3Z,6E,8E)-N-(4-acetamido-3-hydroxybutyl)-2-hydroxy-4,8-dimethylundeca-3,6,8-trienamide on the basis of extensive NMR and MS spectroscopic data. 相似文献
115.
Okabe T Yamazaki Y Shiotani M Suzuki T Shiohara M Kasuga E Notake S Yanagisawa H 《Microbiological research》2010,165(1):11-20
Haemophilus influenzae is a common pathogen of respiratory infections. We examined whether beta-lactamase-negative ampicillin-resistant (BLNAR) strains that are known to have ampicillin resistance due to a substitution of amino acid of penicillin binding protein (PBP)-3, differ from beta-lactamase-negative ampicillin-susceptible strains with regard to invasion of bronchial epithelium. After 3h incubation of each of 34 beta-lactamase-negative ampicillin-susceptible and 57 BLNAR strains in the presence of BEAS-2B cells, a human bronchial epithelium cell line, extracellular bacteria were killed using gentamicin and intracellular bacteria numbered. All nine strains in which the efficiency of invasion was 1% or higher were BLNAR strains. The rate of invasion was significantly greater in strains with PBP-3 amino acid substitution (Met377 to Ile, Ser385 to Thr, Leu389 to Phe, and Asn526 to Lys) (n=34) than in those with no amino acid substitution. Electron microscopy showed that high invasive BLNAR strains were observed in cytoplasm of BEAS-2B cell layer. The injured cells were 9.44+/-1.76% among attaching cells examined by trypan blue staining after 6h. These data may suggest that the amino acid substitution of the PBP in BLNAR strains may at least partly play roles in macropinocytosis, leading to the invasion and injury to epithelial cells. 相似文献
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Previous studies on the activity of the rice Gα promoter using a β-Glucuronidase (GUS) reporter construct indicated that Gα expression was highest in developing organs and changed in a developmental stage-dependent manner. In this paper, GUS activity derived from the rice Gα promoter was analyzed in seeds and developing leaves. In seeds, GUS activity was detected in the aleurone layer, embryo, endosperm and scutellar epithelium. In developing leaves, the activity was detected in the mesophyll tissues, phloem and xylem of the leaf sheath and in the mesophyll tissue of the leaf blade. The activity in the aleurone layer and scutellar epithelium suggests that the Gα subunit may be involved in gibberellin signaling. The activity in the mesophyll tissues of the leaf blade suggests that the Gα subunit may be related to the intensity of disease resistance. The pattern of the activity in the developing leaf also indicates that the expression of Gα follows a developmental profile at the tissue level.Key words: expression pattern, Gα subunit, GUS staining pattern, heterotrimeric G protein, riceThe rice mutant d1 is deficient in the heterotrimeric G protein α subunit (Gα). Recently it was found that the dwarfism phenotype of d1 is due to a reduction in cell numbers.1 This discovery has led to new questions regarding how rice Gα regulates cell number, and which other signaling molecules are involved in this process in various tissues and at different development stages. Studies of d1 suggest that rice Gα participates in both gibberellin signaling2–4 and brassinosteroid signaling.5–8 Promoter studies using the β-Glucuronidase (GUS) reporter indicate that Gα expression is highest in developing organs.1 In this paper, we report on the expression pattern of a Gα promoter::GUS construct in seeds and developing leaves of rice. 相似文献
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Anjana Jajoo Sonal Mathur Pooja Mehta Miho Yoshoika Suleyman I. Allakhverdiev Yasusi Yamamoto 《Journal of bioenergetics and biomembranes》2010,42(1):47-53
Chloride is an indispensable factor for the functioning of oxygen evolving complex (OEC) and has protective and activating
effects on photosystem II. In this study we have investigated mainly by EPR, the properties of chloride-sufficient, chloride-deficient
and chloride-depleted thylakoid membranes and photosystem II enriched membranes from spinach. The results on the effects of
different chloride depletion methods on the structural and functional aspects of photosystem II showed that chloride-depletion
by treating PS II membranes with high pH is a relatively harsh way causing a significant and irreparable damage to the PS
II donor side. Damage to the acceptor side of PS II was recovered almost fully in chloride-deficient as well as chloride-depleted
PS II membranes. 相似文献
118.
Sakai H Tagawa Y Tamai M Motoyama H Ogawa S Soeda J Nakata T Miyagawa S 《Biochemical and biophysical research communications》2010,403(3-4):298-304
Hepatic stem/progenitor cells are one of several cell sources that show promise for restoration of liver mass and function. Although hepatic progenitor cells (HPCs), including oval cells, are induced by administration of certain hepatotoxins in experimental animals, such a strategy would be inappropriate in a clinical setting. Here, we investigated the possibility of isolating HPCs in a portal branch-ligated liver model without administration of any chemical agents. A non-parenchymal cell fraction was prepared from the portal branch-ligated or non-ligated lobe, and seeded onto plates coated with laminin. Most of the cells died, but a small number were able to proliferate. These proliferating cells were cloned as portal branch ligation-stimulated hepatic cells (PBLHCs) by the limiting dilution method. The PBLHCs expressed cytokeratin19, albumin, and Hmga2. The PBLHCs exhibited metabolic functions such as detoxification of ammonium ions and synthesis of urea on Matrigel-coated plates in the presence of oncostatin M. In Matrigel mixed with type I collagen, the PBLHCs became rearranged into cystic and tubular structures. Immunohistochemical staining demonstrated the presence of Hmga2-positive cells around the interlobular bile ducts in the portal branch-ligated liver lobes. In conclusion, successful isolation of bipotent hepatic progenitor cell clones, PBLHCs, from the portal branch-ligated liver lobes of mice provides the possibility of future clinical application of portal vein ligation to induce hepatic progenitor cells. 相似文献
119.
Capture and blood sampling in wild primate populations are difficult. For this reason, we need to use DNA extracted from the
hair or feces of target animals. The polymerase chain reaction (PCR) method, which amplifies small volumes of DNA, provides
an ideal means for studying DNA variations in wild populations. Three sets of PCR primers which amplify highly polymorphic
(GT/AC)n dinucleotide repetitive regions were synthesized from DNA sequences of Japanese macaques (Macaca fuscata). One of the primer pairs detected at least seven alleles in one captive Japanese macaque group. Also, the fathers of four
offspring whose mothers had died in a captive group of Japanese macaques were identified. In such cases, the father cannot
be determined by the previous DNA fingerprinting method based on the polymorphism of minisatellite DNA. These primers were
further tested with some species of the Cercopithecidae, e.g. grivet monkeys (Cercopithecus aethiops tantalus) and hamadryas baboons (Papio hamadryas). The results obtained suggest that these primers can detect stably inherited polymorphic regions in each species. 相似文献
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