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131.
Milena Damulewicz Agnieszka Loboda Alicja Jozkowicz Jozef Dulak Elzbieta Pyza 《Molecular neurobiology》2017,54(7):4953-4962
The Drosophila retina has an autonomous peripheral circadian clock in which the expression of the gene encoding heme oxygenase (HO) is under circadian control with the ho mRNA peaking at the beginning of the day and in the middle of the night. The function of HO in the retina is unknown, but we observed that it regulates the circadian clock and protects photoreceptors against DNA damage. The decline in HO level increases and decreases the expression of the canonical clock genes period (per) and Clock (Clk), respectively. The opposite result was observed after increasing HO expression. Among three products of HO activity—carbon monoxide (CO), ferrous ions, and biliverdin—the latter has no effect on per and Clk expressions, but CO exerts the same effect as the increase of ho expression. This suggests that HO action on the clock is mediated by CO, which may affect Clk expression during the day and the level of per expression. While ho expression is not stimulated by nitric oxide (NO), NO has the same effect on the clock as HO, increasing Clk expression and decreasing the expression of per. 相似文献
132.
133.
In recent years, transposon insertion polymorphisms have been utilized as molecular markers, and a range of techniques tailored towards identification of insertion sites of various transposable elements have been developed. In the present paper we describe the application of a recently developed DcMaster transposon display system to analyse the genetic diversity of Polish breeding materials of carrot (Daucus carota) and to identify polymorphisms useful for hybrid seed purity testing. Using 3 sets of breeding materials (each consisting of the cytoplasmic male sterility stock, the maintainer, the pollinator, and the corresponding F1 hybrid), we identified 56 DcMTD markers. DcMaster insertion sites proved to be highly polymorphic in cultivated carrot, as 79% of all insertion sites differentiated between individual plants. Fourteen stock-specific DcMTD markers were further selected as potentially useful for hybrid seed purity testing. 相似文献
134.
Bielawska A Bielawski J Szulc ZM Mayroo N Liu X Bai A Elojeimy S Rembiesa B Pierce J Norris JS Hannun YA 《Bioorganic & medicinal chemistry》2008,16(2):1032-1045
Novel isosteric analogs of the ceramidase inhibitors (1S,2R)-N-myristoylamino-phenylpropanol-1 (d-e-MAPP) and (1R,2R)-N-myristoylamino-4'-nitro-phenylpropandiol-1,3 (B13) with modified targeting and physicochemical properties were developed and evaluated for their effects on endogenous bioactive sphingolipids: ceramide, sphingosine, and sphingosine 1-phosphate (Cer, Sph, and S1P) in MCF7 cells as determined by high-performance liquid chromatography-mass spectrometry (HPLC-MS/MS). Time- and dose-response studies on the effects of these compounds on Cer species and Sph levels, combined with structure-activity relationship (SAR) data, revealed 4 distinct classes of analogs which were predominantly defined by modifications of the N-acyl-hydrophobic interfaces: N-acyl-analogs (class A), urea-analogs (class B), N-alkyl-analogs (class C), and omega-cationic-N-acyl analogs (class D). Signature patterns recognized for two of the classes correspond to the cellular compartment of action of the new analogs, with class D acting as mitochondriotropic agents and class C compounds acting as lysosomotropic agents. The neutral agents, classes A and B, do not have this compartmental preference. Moreover, we observed a close correlation between the selective increase of C(16)-, C(14)-, and C(18)-Cers and inhibitory effects on MCF7 cell growth. The results are discussed in the context of compartmentally targeted regulators of Sph, Cer species, and S1P in cancer cell death, emphasizing the role of C(16)-Cer. These novel analogs should be useful in cell-based studies as specific regulators of Cer-Sph-S1P inter-metabolism, in vitro enzymatic studies, and for therapeutic development. 相似文献
135.
Kos-Kudła B Bolanowski M Hubalewska-Dydejczyk A Krzakowski M Marek B Nasierowska-Guttmejer A Lampe P Sworczak K;oraz Pozostali Uczestnicy Konferencji Okragłego Stołu 《Endokrynologia Polska》2008,59(1):68-86
Pancreatic endocrine tumors (PETs) are rare neoplasms of this organ. The majority of PETs are tumors without hormonal activity. In this publication, we present the diagnostic and therapeutic guidelines for the management of these tumors proposed by the Polish Network of Neuroendocrine Tumors. These guidelines refer to biochemical and location diagnostics, including scintygraphy of somatostatin receptors, endoscopic ultrasonography and other anatomical and functional imaging methods. High importance is attached to correct histopathological diagnosis which determines further management of patients with PETs. Antitumor therapy requires multidirectional procedure, and therefore the rules of surgical treatment, biotherapy, chemotherapy and peptide receptor radionuclide therapy are discussed. 相似文献
136.
Crossing experiments within the genus Allium have been carried out for many years. Usually, with the aim of widening genetic variation, edible Alliaceae such as bulb onion, Japanese bunching onion, leek, garlic and shallot have been crossed with each other or with distant vegetable
Allium crops. Interspecific hybridization, especially with wild relatives is considered as the best way of introgression desirable
traits to the crops. By using sexual or somatic hybridization, many important characters, such as: disease and pest resistance,
important metabolites and cytoplasmic male sterility have been transferred to other Allium crops. This review summarises some aspects of the directions of interspecific hybridization in edible Alliaceae and the significance and perspectives of using these hybrids in breeding programmes. 相似文献
137.
138.
Matt Smith Jean Emberlin Alicja Stach Auli Rantio-Lehtimäki Eric Caulton Michel Thibaudon Charlotte Sindt Siegfried Jäger Regula Gehrig Giuseppe Frenguelli Victoria Jato F. Javier Rodríguez Rajo Purificación Alcázar Carmen Galán 《Aerobiologia》2009,25(4):321-332
Relationships between temporal variations in the North Atlantic Oscillation (NAO) and grass pollen counts at 13 sites in Europe, ranging from Córdoba in the south-west and Turku in the north-east, were studied in order to determine spatial differences in the amount of influence exerted by the NAO on the timing and magnitude of grass pollen seasons. There were a number of significant (P < 0.05) relationships between the NAO and start dates of the grass pollen season at the 13 pollen-monitoring sites. The strongest associations were generally recorded near to the Atlantic coast. Several significant correlations also existed between winter averages of the NAO and grass pollen season severity. Traditional methods for predicting the start or magnitude of grass pollen seasons have centred on the use of local meteorological observations, but this study has shown the importance of considering large-scale patterns of climate variability like the NAO. 相似文献
139.
Biodegradation of diesel fuel by a microbial consortium in the presence of 1-alkoxymethyl-2-methyl-5-hydroxypyridinium chloride homologues 总被引:1,自引:0,他引:1
Łukasz Chrzanowski Monika Stasiewicz Mikołaj Owsianiak Alicja Szulc Agnieszka Piotrowska-Cyplik Agnieszka K. Olejnik-Schmidt Bogdan Wyrwas 《Biodegradation》2009,20(5):661-671
Fast development of ionic liquids as gaining more and more attention valuable chemicals will undoubtedly lead to environmental
pollution. New formulations and application of ionic liquids may result in contamination in the presence of hydrophobic compounds,
such as petroleum mixtures. We hypothesize that in the presence of diesel fuel low-water-soluble ionic liquids may become
more toxic to hydrocarbon-degrading microorganisms. In this study the influence of 1-alkoxymethyl-2-methyl-5-hydroxypyridinium
chloride homologues (side-chain length from C3 to C18) on biodegradation of diesel fuel by a bacterial consortium was investigated. Whereas test performed for the consortium cultivated
on disodium succinate showed that toxicity of the investigated ionic liquids decreased with increase in side-chain length,
only higher homologues (C8–C18) caused a decrease in diesel fuel biodegradation. As a result of exposure to toxic compounds also modification in cell surface
hydrophobicity was observed (MATH). Disulphine blue active substances method was employed to determine partitioning index
of ionic liquids between water and diesel fuel phase, which varied from 1.1 to 51% for C3 and C18 homologues, respectively. We conclude that in the presence of hydrocarbons acting as a solvent, the increased bioavailability
of hydrophobic homologues is responsible for the decrease in biodegradation efficiency of diesel fuel. 相似文献
140.
Toshiyuki Miura Mark A. Brockman Arne Schneidewind Michael Lobritz Florencia Pereyra Almas Rathod Brian L. Block Zabrina L. Brumme Chanson J. Brumme Brett Baker Alissa C. Rothchild Bin Li Alicja Trocha Emily Cutrell Nicole Frahm Christian Brander Ildiko Toth Eric J. Arts Todd M. Allen Bruce D. Walker 《Journal of virology》2009,83(6):2743-2755
Human immunodeficiency virus type 1 (HIV-1) elite controllers (EC) maintain viremia below the limit of commercial assay detection (<50 RNA copies/ml) in the absence of antiviral therapy, but the mechanisms of control remain unclear. HLA-B57 and the closely related allele B*5801 are particularly associated with enhanced control and recognize the same Gag240-249 TW10 epitope. The typical escape mutation (T242N) within this epitope diminishes viral replication capacity in chronically infected persons; however, little is known about TW10 epitope sequences in residual replicating viruses in B57/B*5801 EC and the extent to which mutations within this epitope may influence steady-state viremia. Here we analyzed TW10 in a total of 50 B57/B*5801-positive subjects (23 EC and 27 viremic subjects). Autologous plasma viral sequences from both EC and viremic subjects frequently harbored the typical cytotoxic T-lymphocyte (CTL)-selected mutation T242N (15/23 sequences [65.2%] versus 23/27 sequences [85.1%], respectively; P = 0.18). However, other unique mutants were identified in HIV controllers, both within and flanking TW10, that were associated with an even greater reduction in viral replication capacity in vitro. In addition, strong CTL responses to many of these unique TW10 variants were detected by gamma interferon-specific enzyme-linked immunospot assay. These data suggest a dual mechanism for durable control of HIV replication, consisting of viral fitness loss resulting from CTL escape mutations together with strong CD8 T-cell immune responses to the arising variant epitopes.A subset of human immunodeficiency virus type 1 (HIV-1)-infected persons who control viremia to below the limit of detection (<50 RNA copies/ml plasma) without antiviral therapy has been termed elite controllers/suppressors (EC) (2, 3, 6, 13, 32). Some of these individuals have been infected in excess of 30 years, indicating prolonged containment of HIV replication, but the mechanisms associated with this extreme viremia control remain elusive (13). Among EC, certain HLA class I alleles are overrepresented, in particular HLA-B57, strongly suggesting that HIV-1-specific cytotoxic T-lymphocyte (CTL) responses restricted by these alleles may be crucial for viremia control (16, 29, 32). However, to date, there has been no clear explanation as to why some subjects can control viremia but others cannot, even when carrying the same allegedly protective HLA alleles. Moreover, the characteristics of virus-specific immune responses as well as the impact of viral escape mutations on in vitro replicative fitness in persons with different disease outcomes remain unclear.Growing numbers of studies suggest that CTL targeting Gag, particularly the p24 capsid protein, play an important role in controlling viremia (7, 15, 22, 26, 32, 33, 38). Indeed, the most protective HLA class I allele, B57, which is present in over 40% of EC (32), restricts four immunodominant CTL epitopes in the p24 capsid protein. Previous studies have failed to find differences in the recognition of Gag epitopes or in gamma interferon (IFN-γ) responses to HIV proteins between B57-positive (B57+) long-term nonprogressors and B57+ progressors (28). Other studies have shown differences in the frequency of polyfunctional CD8+ T cells between B57+ EC and B57+ progressors (5); likewise, differences in the frequency of IFN-γ/interleukin-2-producing CD8+ T cells between controllers and progressors with protective HLA alleles were reported (16). Recently, Bailey et al. reported that plasma viruses in B57+ EC can harbor CTL escape mutations in the Gag protein, and in some cases these autologous variants were recognized by CTL (3). However, since there were no comparisons to progressors, it is unclear whether the viral variants that were detected or the apparent de novo CTL responses to the variant viruses are characteristic features among B57+ persons who maintain persistent control.Of the four immunodominant Gag CTL epitopes restricted by HLA-B57, TW10 (TSTLQEQIGW [Gag residues 240 to 249]) is known to be the earliest target in acute infection (1, 11, 36), therefore likely playing an important role in defining the plasma viral load set point. This epitope is also known to be presented by the closely related B*5801 allele, which is also associated with viral control (21). One of the most frequently detected mutations within this epitope, T242N, is known to occur rapidly and almost universally after acute infection in persons expressing HLA-B57/B*5801 (11, 17, 23). The same mutation has been shown to have a negative impact on viral replication capacity (VRC) by both clinical observation and in vitro experiments (8, 23, 25). Moreover, as plasma viral load increases, compensatory mutations accumulate, restoring VRC to some extent (8). Additional studies, predominantly with children, indicated that some TW10 escape variants may be targeted by specific immune responses (17). Together, these data suggest a hypothesis to explain the diverse disease courses among B57+ subjects, namely, that a combination of fitness cost by CTL escape from the TW10 response, variable accumulation of compensatory mutations, and variable generation of specific CTL responses to the new variant influence plasma viral loads.In this study, we investigated plasma viral sequences and IFN-γ-specific enzyme-linked immunospot (ELISPOT) assay responses to autologous Gag TW10 sequences in HLA-B57/B*5801-positive EC and compared these data to those obtained from persons with detectable viremia. Our results indicate that the TW10 T242N mutation does not differentiate HLA-B57/B*5801 EC from those with viremia and that CTL responses to this variant epitope are frequently detected in both viremic and aviremic subjects. However, some rare variants within and flanking this epitope were observed exclusively in HIV controllers, most of which not only reduced VRC but also were recognized by specific CTL at a high magnitude. These data suggest that the additive effects of both CTL-mediated selection for less fit viral variants and CD8 T-cell responses to the variant viruses contribute to strict viremia control in HLA-B57/B*5801-positive controllers. 相似文献