全文获取类型
收费全文 | 416篇 |
免费 | 32篇 |
国内免费 | 1篇 |
出版年
2023年 | 5篇 |
2022年 | 1篇 |
2021年 | 13篇 |
2020年 | 2篇 |
2019年 | 6篇 |
2018年 | 12篇 |
2017年 | 11篇 |
2016年 | 15篇 |
2015年 | 21篇 |
2014年 | 19篇 |
2013年 | 20篇 |
2012年 | 16篇 |
2011年 | 28篇 |
2010年 | 33篇 |
2009年 | 23篇 |
2008年 | 26篇 |
2007年 | 25篇 |
2006年 | 23篇 |
2005年 | 21篇 |
2004年 | 25篇 |
2003年 | 12篇 |
2002年 | 18篇 |
2001年 | 6篇 |
1999年 | 8篇 |
1998年 | 6篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1986年 | 4篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 5篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1975年 | 1篇 |
1971年 | 1篇 |
1970年 | 2篇 |
1969年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有449条查询结果,搜索用时 15 毫秒
1.
Tarun K. Dam Manju Sarkar Jharna Ghosal Amalesh Choudhury 《Molecular and cellular biochemistry》1992,117(1):1-9
Control Analysis has been carried out in the first steps of a rat liver glycolytic system. Attention has been focused on the effect of several glucose concentrations on the control, particularly regarding the role of glucokinase. From kinetic studies of the whole metabolic system we have obtained information on the flux variation under different glucose concentrations. This information together with the kinetics of glucokinase has allowed us to calculate Flux Control and Elasticity Coefficients for glucokinase and the Response Coefficient of the system with respect to glucose. The changes in of the value of Flux Control Coefficients demonstrates that in conditions of low glucose concentration, glucokinase is the main enzyme in controlling the flux through the pathway, but at high glucose concentration the control moves to phosphofructokinase. Next, we have compared our results with those obtained with the shortening and titration method, previously described (Torres, N.V., Mateo, F., Mélendez-Hevia, E. and Kacser, H., (1986) Biochem. J. 234, 169–174; Torres, N.V. and Meléndez-Hevia, E. 1991. Molec. Cell. Biochem. 101, 1–10). Furthermore, from knowledge of the enzyme kinetics of the system we have been able to build a model of the pathway that allows us computer similation of its behavior and calculation of the Flux Control Coefficient profile at different glucose concentrations. By the three methods the results correlate, supporting the use of the pathway substrate as external modulator of the metabolic system as a tool for practical application of Control Analysis. 相似文献
2.
The cotyledon of the seed of Mirabilis jalapa was found to contain a
-glucan. Methylation, periodate oxidation, and graded and enzymic hydrolysis studies were conducted to elucidate its structure. For every 38
-glucosyl residues therein, 34 are (1→4)- and 3 are (1→3)-linked; the
-glucosyl unit at the branch point is linked through O-1, O-2, and O-4. In some places in the chain, there are at least three (1→3)-linked
-glucosyl residues in a sequence. Both α- and β-
-glucosidic linkages are present in the polysaccharide, the former preponderating. The
-glucan gave with iodine a faint blue color that had λmax 420 nm. 相似文献
3.
Aerobiologia - Bioaerosols have gained importance in atmospheric sciences in the past few decades. Their exposure upsurges the health problems in sensitive population and is also known to... 相似文献
4.
Bahare Shokoohian Babak Negahdari Hamidreza Aboulkheyr Es Manuchehr Abedi-Valugerdi Kaveh Baghaei Tarun Agarwal Tapas Kumar Maiti Moustapha Hassan Mustapha Najimi Massoud Vosough 《Journal of cellular and molecular medicine》2021,25(18):8602-8614
Hepatocellular carcinoma (HCC), the most common type of liver cancer, is usually a latent and asymptomatic malignancy caused by different aetiologies, which is a result of various aberrant molecular heterogeneity and often diagnosed at advanced stages. The incidence and prevalence have significantly increased because of sedentary lifestyle, diabetes, chronic infection with hepatotropic viruses and exposure to aflatoxins. Due to advanced intra- or extrahepatic metastasis, recurrence is very common even after radical resection. In this paper, we highlighted novel therapeutic modalities, such as molecular-targeted therapies, targeted radionuclide therapies and epigenetic modification-based therapies. These topics are trending headlines and their combination with cell-based immunotherapies, and gene therapy has provided promising prospects for the future of HCC treatment. Moreover, a comprehensive overview of current and advanced therapeutic approaches is discussed and the advantages and limitations of each strategy are described. Finally, very recent and approved novel combined therapies and their promising results in HCC treatment have been introduced. 相似文献
5.
6.
Antonia L. Dow Tiffany V. Lin Elena H. Chartoff David Potter Donna L. McPhie Ashlee V. Van’t Veer Allison T. Knoll Kristen N. Lee Rachael L. Neve Tarun B. Patel Dost Ongur Bruce M. Cohen William A. Carlezon Jr 《PloS one》2015,10(3)
Both the development and relief of stress-related psychiatric conditions such as major depression (MD) and post-traumatic stress disorder (PTSD) have been linked to neuroplastic changes in the brain. One such change involves the birth of new neurons (neurogenesis), which occurs throughout adulthood within discrete areas of the mammalian brain, including the dorsal hippocampus (HIP). Stress can trigger MD and PTSD in humans, and there is considerable evidence that it can decrease HIP neurogenesis in laboratory animals. In contrast, antidepressant treatments increase HIP neurogenesis, and their efficacy is eliminated by ablation of this process. These findings have led to the working hypothesis that HIP neurogenesis serves as a biomarker of neuroplasticity and stress resistance. Here we report that local alterations in the expression of Sprouty2 (SPRY2), an intracellular inhibitor of growth factor function, produces profound effects on both HIP neurogenesis and behaviors that reflect sensitivity to stressors. Viral vector-mediated disruption of endogenous Sprouty2 function (via a dominant negative construct) within the dorsal HIP of adult rats stimulates neurogenesis and produces signs of stress resilience including enhanced extinction of conditioned fear. Conversely, viral vector-mediated elevation of SPRY2 expression intensifies the behavioral consequences of stress. Studies of these manipulations in HIP primary cultures indicate that SPRY2 negatively regulates fibroblast growth factor-2 (FGF2), which has been previously shown to produce antidepressant- and anxiolytic-like effects via actions in the HIP. Our findings strengthen the relationship between HIP plasticity and stress responsiveness, and identify a specific intracellular pathway that could be targeted to study and treat stress-related disorders. 相似文献
7.
Ira Vashisht Prashant Mishra Tarun Pal Sreekrishna Chanumolu Tiratha Raj Singh Rajinder Singh Chauhan 《Planta》2015,241(5):1269-1270
8.
The ratio of gelatin to sodium carboxymethyl cellulose (SCMC) at which maximum yield was obtained was optimized. This optimized
ratio of gelatin to SCMC along with other parameters was used to prepare microparticles of different sizes. Vegetable oil
was used as emulsion medium. Effect of various factors like amount of surfactant, concentration of polymer on the formation,
and size of the microparticles was investigated. These microparticles were used as carrier for isoniazid. Among different
cross-linkers, glutaraldehyde was found to be the most effective cross-linker at the temperature and pH at which the reaction
was carried out. The loading efficiency and release behavior of loaded microparticles were found to be dependent on the amount
of cross-linker used, concentration of drug, and time of immersion. Maximum drug loading efficiency was observed at higher
immersion time. The release rate of isoniazid was more at higher pH compared to that of at lower pH. The sizes of the microparticles
were investigated by scanning electron microscope. In all the cases, the microparticles formed were found spherical in shape
except to those at low stirring speed where they were agglomerated. Fourier transform infrared study indicated the successful
incorporation of isoniazid into the microparticles. Differential scanning calorimetry study showed a molecular level dispersion
of isoniazid in the microparticles. X-ray diffraction study revealed the development of some crystallinity due to the encapsulation
of isoniazid. 相似文献
9.
10.
On single and multiple models of protein families for the detection of remote sequence relationships