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81.
82.
Mahim Khan Muhammad Qasim Usman Ali Ashfaq Sobia Idrees Masoud Shah 《Bioinformation》2013,9(14):710-714
Background:
HCV has become a leading cause of liver cirrhosis and hepatocellular carcinoma and is a major health concern worldwide. To date,
there is no vaccine available in the market to tackle this disease, therefore there is a strong need to develop antiviral compounds
that can target all genotypes of HCV with the same efficiency. Medicinal plants have low cost and are less toxic therefore, extracts
of medicinal plants can serve as important antiviral agents against HCV. This study was designed to screen phytochemicals of
Accacia nilotica to find a potent drug candidate that can inhibit HCV infection effectively.Results:
Docking of NS3/4A protease and Flavonoids of Accacia nilotica revealed that most of the flavonoids bound deeply with the active
site of NS3/4A protease. Compound 01 showed a high ranking on docking score. All other compounds also showed reliable
docking scores and had interactions with the binding cavity of NS3/4A protease, suggesting them as a potent drug candidate to
block HCV replication.Conclusion:
To recognize binding interactions of Accacia nilotica phytochemicals with NS3/4A protease, molecular docking was performed to
find potential inhibitor against NS3/4A protease of HCV. After post docking analysis, important interactions were found between
active compounds and active site of NS3/4A protease. It can be concluded from the study that phytochemicals of Accacia nilotica
may serve as a potential drug candidate with relatively simple structural changes against HCV NS3/4A protease. 相似文献
83.
Benjamin Drew Rockett Mark Melton Mitchel Harris Lance C. Bridges Saame Raza Shaikh 《The Journal of nutritional biochemistry》2013,24(11):1810-1816
Fish oil-enriched long chain n-3 polyunsaturated fatty acids disrupt the molecular organization of T-cell proteins in the immunological synapse. The impact of fish oil derived n-3 fatty acids on antigen-presenting cells, particularly at the animal level, is unknown. We previously demonstrated B-cells isolated from mice fed with fish oil-suppressed naïve CD4+ T-cell activation. Therefore, here we determined the mechanistic effects of fish oil on murine B-cell major histocompatibility complex (MHC) class II molecular distribution using a combination of total internal reflection fluorescence, Förster resonance energy transfer and confocal imaging. Fish oil had no impact on presynaptic B-cell MHC II clustering. Upon conjugation with transgenic T-cells, fish-oil suppressed MHC II accumulation at the immunological synapse. As a consequence, T-cell protein kinase C theta (PKCθ) recruitment to the synapse was also diminished. The effects were independent of changes in B-T cell adhesion, as measured with microscopy, flow cytometry and static cell adhesion assays with select immune ligands. Given that fish oil can reorganize the membrane by lowering membrane cholesterol levels, we then compared the results with fish oil to cholesterol depletion using methyl-B-cyclodextrin (MβCD). MβCD treatment of B-cells suppressed MHC II and T-cell PKCθ recruitment to the immunological synapse, similar to fish oil. Overall, the results reveal commonality in the mechanism by which fish oil manipulates protein lateral organization of B-cells compared to T-cells. Furthermore, the data establish MHC class II lateral organization on the B-cell side of the immunological synapse as a novel molecular target of fish oil. 相似文献
84.
Hisham Mohammed Clive D’Santos Aurelien A. Serandour H. Raza Ali Gordon D. Brown Alan Atkins Oscar M. Rueda Kelly A. Holmes Vasiliki Theodorou Jessica L.L. Robinson Wilbert Zwart Amel Saadi Caryn S. Ross-Innes Suet-Feung Chin Suraj Menon John Stingl Carlo Palmieri Carlos Caldas Jason S. Carroll 《Cell reports》2013,3(2):342-349
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85.
Atika?MansoorEmail author Lubna?Ali Noor-ul?Sabah Asraf?Hussain?Hashmi Mohammad?Haroon?Khan Syed?Ali?Raza?Kazmi Nafees?Ahmad Saima?Siddiqi Khalid?Mehmood?Khan 《Virology journal》2013,10(1):352
Background
Hepatitis C virus (HCV) is a major cause of liver cirrhosis and hepatocellular carcinoma and infects about 3% world population. Response to interferon therapy depends upon the genotype of the virus and factors associated with the host. Despite a good response to interferon therapy, a considerable number of genotype 3a infected patients remains unalleviated.Results
In total forty-nine patients including twenty-five non-responders (non-SVR) and twenty-four responders (SVR) were recruited. Patients were tested for viral status at different intervals and the isolated RNA was sequenced for the NS5A region in both groups. The comparison of PKRBD of HCV between the SVR and non-SVR patients did not confirm any significant difference in the number of mutations. However, when the sequence downstream to the PKRBD of NS5A was compared, two important statistically significant mutations were observed; at positions 2309 (Ala to Ser) and 2326 (Gly to Ala). These mutations were then analysed for tertiary protein structure and important structural changes were observed. Statistically significant difference was also observed when age groups of patients were compared; younger patients showed better response than the older ones.Conclusions
The region between PKRBD and IRRDR may be important for prediction of response to IFN therapy for genotype 3a. ISDR and PKRBD have not shown any involvement in treatment response. Further functional analyses of these findings can help in understanding the involvement of the NS5A region in interferon treatment of HCV-3a infected patients.86.
This article looks at the steady flow of Micropolar fluid over a stretching surface with heat transfer in the presence of Newtonian heating. The relevant partial differential equations have been reduced to ordinary differential equations. The reduced ordinary differential equation system has been numerically solved by Runge-Kutta-Fehlberg fourth-fifth order method. Influence of different involved parameters on dimensionless velocity, microrotation and temperature is examined. An excellent agreement is found between the present and previous limiting results. 相似文献
87.
88.
Sumon Kumar Das Mohammod Jobayer Chisti Sayeeda Huq Mohammad Abdul Malek Lana Vanderlee Guddu Kaur Mohammed Abdus Salam Tahmeed Ahmed Abu Syed Golam Faruque Abdullah Al Mamun 《PloS one》2013,8(8)
Background
The present study aimed to determine the clinical characteristics and etiology of overweight and obese (OO) individuals with diarrhea attending an urban Dhaka Hospital, International Centre for Diarrheal Disease Research (icddr,b), Bangladesh.Methods
Total of 508 under-5 children, 96 individuals of 5–19 years and 1331 of >19 years were identified as OO from the Diarrheal Disease Surveillance System (DDSS) between 1993–2011. Two comparison groups such as well-nourished and malnourished individuals from respective age stratums were selected.Results
Isolation rate of rotavirus was higher among OO under-5 children compared to malnourished group (46% vs. 28%). Rotavirus infection among OO individuals aged 5–19 years (9% vs. 3%) (9% vs. 3%) and >19 years (6% vs. 4%) (6% vs. 3%) was higher compared to well-nourished and malnourished children. Conversely, Vibrio cholerae was lower among all OO age groups compared to well-nourished and malnourished ones. Shigella (4% vs. 6%) (4% vs. 8%), and Campylobacter (3% vs. 5%) (3% vs. 5%) were lower only among OO in >19 years individuals compared to their counterparts of the same age stratum. Salmonella was similarly isolated in all age strata and nutritional groups. In multinomial logistic regression among under-5 children, significant association was observed only with use of antimicrobials at home [OR-1.97] and duration of hospital stay [OR-0.68]. For individuals aged 5–19 years, use of antimicrobials at home (OR-1.83), some or severe dehydration (OR-3.12), having received intravenous saline (OR-0.46) and rotavirus diarrhea (OR-2.96) were found to be associated with OO respectively. Moreover, significant associations were also found for duration of diarrhea before coming to hospital (>24 hours) (OR-1.24), Shigella (OR-0.46), and Campylobacter (OR-0.58) among >19 years OO individuals along with other associated co-variates in 5–19 years group (all p<0.05).Conclusion and significance
Higher proportion of OO were infected with rotavirus and a greater proportion of them used antimicrobials before coming to the hospital. 相似文献89.
Sharifah Nurain Syed Zanaruddin Pei San Yee Seen Yii Hor Yink Heay Kong Wan Maria Nabillah Wan Abd Ghani Wan Mahadzir Wan Mustafa Rosnah Binti Zain Stephen S. Prime Zainal Ariff Abd Rahman Sok-Ching Cheong 《PloS one》2013,8(11)
Objectives
The frequency of common oncogenic mutations and TP53 was determined in Asian oral squamous cell carcinoma (OSCC).Materials and Methods
The OncoCarta™ panel v1.0 assay was used to characterize oncogenic mutations. In addition, exons 4-11 of the TP53 gene were sequenced. Statistical analyses were conducted to identify associations between mutations and selected clinico-pathological characteristics and risk habits.Results
Oncogenic mutations were detected in PIK3CA (5.7%) and HRAS (2.4%). Mutations in TP53 were observed in 27.7% (31/112) of the OSCC specimens. Oncogenic mutations were found more frequently in non-smokers (p = 0.049) and TP53 truncating mutations were more common in patients with no risk habits (p = 0.019). Patients with mutations had worse overall survival compared to those with absence of mutations; and patients who harbored DNA binding domain (DBD) and L2/L3/LSH mutations showed a worse survival probability compared to those patients with wild type TP53. The majority of the oncogenic and TP53 mutations were G:C > A:T and A:T > G:C base transitions, regardless of the different risk habits.Conclusion
Hotspot oncogenic mutations which are frequently present in common solid tumors are exceedingly rare in OSCC. Despite differences in risk habit exposure, the mutation frequency of PIK3CA and HRAS in Asian OSCC were similar to that reported in OSCC among Caucasians, whereas TP53 mutations rates were significantly lower. The lack of actionable hotspot mutations argue strongly for the need to comprehensively characterize gene mutations associated with OSCC for the development of new diagnostic and therapeutic tools. 相似文献90.
Syed?Haider Daryl?Waggott Emilie?Lalonde Clement?Fung Fei-Fei?Liu Paul?C.?BoutrosEmail author 《Source code for biology and medicine》2016,11(1):14