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961.
Mongolian gerbils and Wistar rats were inoculated orally with 240 and 2,500 Toxocara cati embryonated eggs, respectively, to evaluate the larval recovery in different tissues and organs, such as the liver, lungs, heart, kidney, and skeletal muscles after 5, 30, 49, 70, and 92 days post-infection (PI). Larval recovery rates were 1.7-30.0% in Mongolian gerbils on days 5-92 PI and 0.2-3.8% in rats on the same days. These results indicate that Mongolian gerbils and Wistar rats are suitable experimental paratenic hosts for the study of neurological toxocariasis as well as visceral toxocariasis. 相似文献
962.
In this paper a new method based on artificial neural networks (ANN), is introduced for identifying pathogenic antibodies in Systemic Lupus Erythmatosus (SLE). dsDNA binding antibodies have been implicated in the pathogenesis of this autoimmune disease. In order to identify these dsDNA binding antibodies, the protein sequences of 42 dsDNA binding and 608 non-dsDNA binding antibodies were extracted from Kabat database and encoded using a physicochemical property of their amino acids namely Hydrophilicity. Encoded antibodies were used as the training patterns of a general regression neural network (GRNN). Simulation results show that the accuracy of proposed method in recognizing dsDNA binding antibodies is 83.2%. We have also investigated the roles of the light and heavy chains of anti-dsDNA antibodies in binding to DNA. Simulation results concur with the published experimental findings that in binding to DNA, the heavy chain of anti-dsDNA is more important than their light chain. 相似文献
963.
Rahman LN Chen L Nazim S Bamm VV Yaish MW Moffatt BA Dutcher JR Harauz G 《Biochimie et biologie cellulaire》2010,88(5):791-807
Dehydrins are intrinsically disordered (unstructured) proteins that are expressed in plants experiencing stressful conditions such as drought or low temperature. Dehydrins are typically found in the cytosol and nucleus, but also associate with chloroplasts, mitochondria, and the plasma membrane. Although their role is not completely understood, it has been suggested that they stabilize proteins or membrane structures during environmental stress, the latter association mediated by formation of amphipathic α-helices by conserved regions called the K-segments. Thellungiella salsuginea is a crucifer that thrives in the Canadian sub-Arctic (Yukon Territory) where it grows on saline-rich soils and experiences periods of both extreme cold and drought. We have cloned and expressed in Escherichia coli two dehydrins from this plant, denoted TsDHN-1 (acidic) and TsDHN-2 (basic). Here, we show using transmission-Fourier transform infrared (FTIR) spectroscopy that ordered secondary structure is induced and stabilized in these proteins by association with large unilamellar vesicles emulating the lipid compositions of plant plasma and organellar membranes. Moreover, this induced folding is enhanced at low temperatures, lending credence to the hypothesis that dehydrins stabilize plant outer and organellar membranes in conditions of cold. 相似文献
964.
Mahmoud Sitohy Bernard Besse Sylviane Billaudel Thomas Haertlé Jean-Marc Chobert 《Probiotics and antimicrobial proteins》2010,2(2):104-111
Antiviral activity of methylated β-lactoglobulin (Met-BLG) against H3N2 infected into MDCK cell lines depended on concentration of Met-BLG, viral load, and duration of infection. IC50% of the hemagglutination activity for 1 and 0.2 MOI (multiplicity of infection) after 24 h of incubation at 37 °C in the presence of 5% CO2 were 20 ± 0.8 and 17 ± 0.7 μg mL?1 Met-BLG, respectively. Longer incubation period (4 days) was associated with low IC50% of the hemagglutination activity (7.1 ± 0.3 μg mL?1 Met-BLG) and low IC50% of immuno-fluorescence of viral nucleoproteins (9.7 ± 0.4 μg mL?1 Met-BLG) when using 0.2 and 0.1 MOI, respectively. A concentration of 25 μg mL?1 of Met-BLG reduced the amount of replicating virus by about 2 and 1.3 logs when the viral load was 0.01 and 0.1 MOI, respectively, while higher concentrations reduced it by about 5–6 logs. Antiviral action of Met-BLG was coupled with a cellular protective action, which reached 100% when using 0.01 and 0.1 MOI and 83% when using 1.0 MOI. The time of Met-BLG addition after the viral infection was determinant for its antiviral efficacy and for its protection of the infected MDCK cell lines. Anti-hemagglutination action and cell protective action decreased gradually and in parallel with the delay in the time of Met-BLG addition to disappear totally after 10 h delay. 相似文献
965.
Bahman Shams Esfandabad Mahmoud Karami Mahmoud-Reza Hemami Borhan Riazi Mohammad-Bagher Sadough 《European Journal of Wildlife Research》2010,56(6):883-894
Wild goat (Capra aegagrus) is one of the highly valued but threatened ungulates of Iran. Seasonal habitat use of wild goat was studied from October
2006 to September 2008 in Haftad Gholleh Protected Area, central Iran. We developed averaged logistic regression models based
on Akaike Information Criterion weights for each season. The obtained habitat suitability models showed high sensitivity (greater
than 88%) for all evaluation datasets. Wild goat habitat use was positively related with steep slopes, areas near rocky substrates
and water sources, west-facing slopes and areas far from roads in all seasons. Core zones of protected area covered nearly
70% of suitable habitats for wild goats, predicted by logistic regression models. Northern core zone covered more than 61%
of predicted suitable habitats, which should receive more attention in management actions. The southern core zone boundaries
should be considered to increase the encompassed suitable habitats. There was a substantial overlap between seasonal suitable
habitats with the highest overlap observed between spring and summer and summer and fall. 相似文献
966.
Sampada B. Upadhye Swapnil J. Kulkarni Soumyajit Majumdar Mitchell A. Avery Waseem Gul Mahmoud A. ElSohly Michael A. Repka 《AAPS PharmSciTech》2010,11(2):509-517
Δ9-Tetrahydrocannabinol hemisuccinate (THC-HS), an ester prodrug of Δ9-tetrahydrocannabinol (THC) has been investigated for its potential to form inclusion complexes with modified synthetic beta-cyclodextrins
(CDs). Phase solubility studies were performed to determine the stoichiometric ratio of complexation of THC-HS with random
methylated beta-cyclodextrin (RAMEB) and 2-hydroxypropyl beta-cyclodextrin (HPBCD). THC-HS/RAMEB and THC-HS/HPBCD solid systems
were prepared by lyophilization and the lyophilized complexes were characterized by Fourier transform infrared (FT-IR) spectroscopy,
proton nuclear magnetic spectroscopy, and molecular modeling techniques. The formation of inclusion complexes of THC-HS/RAMEB
and THC-HS/HPBCD was demonstrated by an AL type curve with the slopes less than unity by the phase solubility method. The association constants for THC-HS/RAMEB and
THC-HS/HPBCD were found to be 562.48 and 238.83 M−1, respectively. The stoichiometry of both of the complexes was found to be 1:1 as determined from the Job's plot. This was
confirmed by 1H NMR and FT-IR techniques. The results obtained from the molecular modeling studies were in accordance with the data obtained
from nuclear magnetic resonance and FT-IR. The docking studies revealed the most probable mode of binding of THC-HS with RAMEB
in which the alkyl chain was submerged in the hydrophobic pocket of the CD molecule and hydrogen bonding interactions were
observed between the hemisuccinate ester side chain of THC-HS and the rim hydroxy groups of RAMEB. The solubility of THC-HS
was significantly higher in RAMEB compared to HPBCD. Solid dispersions of THC-HS with CDs will be further utilized to develop
oral formulations of THC-HS with enhanced bioavailability. 相似文献
967.
Mahmoud A. Ghannoum Richard J. Jurevic Pranab K. Mukherjee Fan Cui Masoumeh Sikaroodi Ammar Naqvi Patrick M. Gillevet 《PLoS pathogens》2010,6(1)
The oral microbiome–organisms residing in the oral cavity and their collective genome–are critical components of health and disease. The fungal component of the oral microbiota has not been characterized. In this study, we used a novel multitag pyrosequencing approach to characterize fungi present in the oral cavity of 20 healthy individuals, using the pan-fungal internal transcribed spacer (ITS) primers. Our results revealed the “basal” oral mycobiome profile of the enrolled individuals, and showed that across all the samples studied, the oral cavity contained 74 culturable and 11 non-culturable fungal genera. Among these genera, 39 were present in only one person, 16 genera were present in two participants, and 5 genera were present in three people, while 15 genera (including non-culturable organisms) were present in ≥4 (20%) participants. Candida species were the most frequent (isolated from 75% of participants), followed by Cladosporium (65%), Aureobasidium, Saccharomycetales (50% for both), Aspergillus (35%), Fusarium (30%), and Cryptococcus (20%). Four of these predominant genera are known to be pathogenic in humans. The low-abundance genera may represent environmental fungi present in the oral cavity and could simply be spores inhaled from the air or material ingested with food. Among the culturable genera, 61 were represented by one species each, while 13 genera comprised between 2 and 6 different species; the total number of species identified were 101. The number of species in the oral cavity of each individual ranged between 9 and 23. Principal component (PCO) analysis of the obtained data set followed by sample clustering and UniFrac analysis revealed that White males and Asian males clustered differently from each other, whereas both Asian and White females clustered together. This is the first study that identified the “basal mycobiome” of healthy individuals, and provides the basis for a detailed characterization of the oral mycobiome in health and disease. 相似文献
968.
Saad Zaky Hebat-Allah Rashed Ehab Faouzy Mahmoud Rezk Abdelwahed Hussein 《Cellular immunology》2010,265(2):97-104
The aim of this study was to determine the clinicopathologic features and Hepatitis B virus genotypes in HBV-infected patients in the Upper Egypt. Eighty-three HBsAg-positive patients (28 carriers, 14 with chronic hepatitis, 32 with liver cirrhosis and 9 with hepatocellular carcinoma) were enrolled. Blood was collected and serum samples obtained were screened for Hepatitis markers genotyping was conducted for 6 HBV genotypes (A through F) using a method for genotyping HBV by primer specific polymerase chain reaction. Genotype D was the only genotype detected in different clinical forms of chronic HBV infection (carriers, chronic hepatitis, cirrhosis and hepatocellular carcinoma) and, in all patients who had elevated or normal alanine aminotransferase levels and in all ages. HBeAg was absent in 78 patients suggesting the presence of pre-core or core mutations. Positive correlation was found among serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), histological activity index and grade of hepatitis. This study provides the first indication about the clinicopathologic features of HBV-infected patients in the Upper Egypt. It also reports the predominance of genotype D in this region. 相似文献
969.
Oikonomopoulou K Hansen KK Saifeddine M Vergnolle N Tea I Diamandis EP Hollenberg MD 《Biological chemistry》2006,387(6):677-685
Serine proteinases, like trypsin, can play a hormone-like role by triggering signal transduction pathways in target cells. In many respects these hormone-like actions of proteinases can now be understood in terms of the pharmacodynamics of the G protein-coupled 'receptor' responsible for the cellular actions of thrombin (proteinase-activated receptor-1, or PAR1). PAR1, like the other three members of this receptor family (PAR2, PAR3 and PAR4), has a unique mechanism of activation involving the proteolytic unmasking of an N-terminally tethered sequence that can activate the receptor. The selective activation of each PAR by short synthetic peptides representing these sequences has demonstrated that PAR1, PAR2 and PAR4 play important roles in regulating physiological responses ranging from vasoregulation and cell growth to inflammation and nociception. We hypothesise that the tissue kallikreins may regulate signal transduction via the PARs. Although PARs can account for many of their biological actions, kallikreins may also cause effects by mechanisms not involving the PARs. For instance, trypsin activates the insulin receptor and thrombin can act via a mechanism involving its non-catalytic domains. Based on the data we summarise, we propose that the kallikreins, like thrombin and trypsin, must now be considered as important 'hormonal' regulators of tissue function. 相似文献
970.
Arylsulfatase B (ASB) hydrolyzes the desulfation of N-acetylgalactosamine-4-sulfate at the non-reducing terminal of glycosaminoglycans. This enzyme activity was found to be elevated in mice schistosomiasis. In the present study, the catalytic and immunological properties of purified ASB from the liver of Schistosoma-infected mouse was investigated in the presence and absence of the schistosomicidal drugs praziquantel and Commiphora extract. The in vitro effect of praziquantel was found to be inhibitory with a Ki value of 5.5 x 10(-4) M while that of commiphora extract was as an activator. Furthermore, these drugs did not have an observed effect on the immunological properties of ASB with regard to its binding to its polyclonal rabbit antibody. These results indicate that some schistosomicidal drugs may reverse the alteration of the catalytic properties of the enzyme in schistosomiasis. 相似文献