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91.
Lee DY Karnati VV He M Liu-Chen LY Kondaveti L Ma Z Wang Y Chen Y Beguin C Carlezon WA Cohen B 《Bioorganic & medicinal chemistry letters》2005,15(16):3744-3747
Salvinorin A is the most potent naturally occurring opioid agonist yet discovered with high selectivity and affinity for kappa-opioid receptor. To explore its structure and activity relationships, a series of salvinorin A derivatives modified at the C2 position were prepared and studied. These salvinorin A derivatives were screened for binding and functional activities at the human kappa-opioid receptor. Compound 4, containing a methoxymethyl group at the 2-position, was a full kappa-agonist with an EC50 value at 0.6 nM, which is about 7 times more potent than salvinorin A. 相似文献
92.
BACKGROUND: Diabetes mellitus is a chronic metabolic disorder characterized by hyperglycaemia. Increased oxidative stress and decreased antioxidant levels are the leading cause of diabetes and diabetic complications. So it is felt that supplementation of antioxidants may be useful in controlling the glucose levels and to postpone the occurrence of diabetic complications. The objective of our study is to find the influence of antioxidant supplementation (L-ascorbic acid) on tolbutamide activity in normal and diabetic rats. METHODS: L- ascorbic acid/tolbutamide/L-ascorbic acid + tolbutamide were administered orally to 3 different groups of albino rats of either sex in normal and diabetic condition. Blood samples were collected from retro-orbital puncture at different time intervals and were analyzed for blood glucose by GOD-POD method. Diabetes was induced by alloxan 100 mg/kg body weight administered by I.P route. RESULTS: L-ascorbic acid/ tolbutamide produced hypoglycaemic activity in a dose dependant manner in normal and diabetic condition. In the presence of L-ascorbic acid, tolbuatmide produced early onset of action and maintained for longer period compared to tolbutamide matching control. CONCLUSION: Supplementation of antioxidants like L-ascorbic acid was found to improve tolbutamide response in normal and diabetic rats. 相似文献
93.
High-quality RNA from cells isolated by laser capture microdissection 总被引:11,自引:0,他引:11
Mikulowska-Mennis A Taylor TB Vishnu P Michie SA Raja R Horner N Kunitake ST 《BioTechniques》2002,33(1):176-179
Laser capture microdissection (LCM) provides a rapid and simple method for procuring homogeneous populations of cells. However, reproducible isolation of intact RNAfrom these cells can be problematic; the sample may deteriorate before or during sectioning, RNA may degrade during slide staining and LCM, and inadequate extraction and isolation methods may lead to poor recovery. Our report describes an optimized protocol for preparation of frozen sections for LCM using the HistoGene Frozen Section Staining Kit. This slide preparation method is combined with the PicoPure RNA Isolation Kitfor extraction and isolation of RNA from low numbers of microdissected cells. The procedure is easy to perform, rapid, and reproducible. Our results show that the RNA isolated from the LCM samples prepared according to our protocol is of high quality. The RNA maintains its integrity as shown by RT-PCR detection of genes of different abundance levels and by electrophoretic analysis of ribosomal RNA. RNA obtained by this method has also been used to synthesize probes for interrogating cDNA microarray analyses to study expression levels of thousands of genes from LCM samples. 相似文献
94.
Anantha Koteswararao Kanugula Vishnu M. Dhople Uwe V?lker Ramesh Ummanni Srigiridhar Kotamraju 《PloS one》2014,9(9)
Statins are increasingly being recognized as anti-cancer agents against various cancers including breast cancer. To understand the molecular pathways targeted by fluvastatin and its differential sensitivity against metastatic breast cancer cells, we analyzed protein alterations in MDA-MB-231 cells treated with fluvastatin using 2-DE in combination with LC-MS/MS. Results revealed dys-regulation of 39 protein spots corresponding to 35 different proteins. To determine the relevance of altered protein profiles with breast cancer cell death, we mapped these proteins to major pathways involved in the regulation of cell-to-cell signaling and interaction, cell cycle, Rho GDI and proteasomal pathways using IPA analysis. Highly interconnected sub networks showed that vimentin and ERK1/2 proteins play a central role in controlling the expression of altered proteins. Fluvastatin treatment caused proteolysis of vimentin, a marker of epithelial to mesenchymal transition. This effect of fluvastatin was reversed in the presence of mevalonate, a downstream product of HMG-CoA and caspase-3 inhibitor. Interestingly, fluvastatin neither caused an appreciable cell death nor did modulate vimentin expression in normal mammary epithelial cells. In conclusion, fluvastatin alters levels of cytoskeletal proteins, primarily targeting vimentin through increased caspase-3- mediated proteolysis, thereby suggesting a role for vimentin in statin-induced breast cancer cell death. 相似文献
95.
96.
Devendra K. Awasthi Ramaveer Rawat Adesh Kumar Vishnu Kumar 《Journal of plant research》1991,104(1):59-71
All the floral primordia are homologous to leaves in their development inLindenbergia macrostachya. The sepals follow an anterior to posterior sequence of initiation. The petals and stamens are initiated almost simultaneously
but sequentially in order of petals followed by stamens. There is no sign of development of fifth posterior stamen. p ]The
calyx tube is formed by interprimordial growth followed by zonal growth. The combined interprimordial growth between the petal
primordia and growth on the abaxial side of stamen primordia results in the formation of upper corolla tube whereas lower
corolla tube is formed only by zonal growth. The zonal growth extends below the bases of stamen primordia also due to which
they become epipetalous. The placentae arise from the carpellary margins, move inwards and get fused in the lower half and
remain free in the upper part of the ovary. Thus the ovary appears biloeular with axile plaeentation in the lower haler and
unilocular with parietal placentation in the upper half. 相似文献
97.
Abhinav Sharma Vishnu Raman Jungwoo Lee Neil S. Forbes 《Biotechnology and bioengineering》2020,117(8):2540-2555
The mucosal barrier in combination with innate immune system are the first line of defense against luminal bacteria at the intestinal mucosa. Dysfunction of the mucus layer and bacterial infiltration are linked to tissue inflammation and disease. To study host–bacterial interactions at the mucosal interface, we created an experimental model that contains luminal space, a mucus layer, an epithelial layer, and suspended immune cells. Reconstituted porcine small intestinal mucus formed an 880 ± 230 µm thick gel layer and had a porous structure. In the presence of mucus, sevenfold less probiotic and nonmotile VSL#3 bacteria transmigrated across the epithelial barrier compared to no mucus. The higher bacterial transmigration caused immune cell differentiation and increased the concentration of interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNF-α; p < .01). Surprisingly, the mucus layer increased transmigration of pathogenic Salmonella and increased secretion of TNF-α and IL-8 (p < .05). Nonmotile, flagella knockout Salmonella had lower transmigration and caused lower IL-8 and TNF-α secretion (p < .05). These results demonstrate that motility enables pathogenic bacteria to cross the mucus and epithelial layers, which could lead to infection. Using an in vitro coculture platform to understand the interactions of bacteria with the intestinal mucosa has the potential to improve the treatment of intestinal diseases. 相似文献
98.
99.
Manmohit Kalia Vivek Kumar Yadav Pradeep Kumar Singh Deepmala Sharma Himanshu Pandey Shahid Suhail Narvi Vishnu Agarwal 《PloS one》2015,10(8)
Quorum sensing (QS) is a system of stimuli and responses in bacterial cells governed by their population density, through which they regulate genes that control virulence factors and biofilm formation. Despite considerable research on QS and the discovery of new antibiotics, QS-controlled biofilm formation by microorganisms in clinical settings has remained a problem because of nascent drug resistance, which requires screening of diverse compounds for anti-QS activities. Cinnamon is a dietary phytochemical that is traditionally used to remedy digestive problems and assorted contagions, which suggests that cinnamon might contain chemicals that can hinder the QS process. To test this hypothesis, the anti-QS activity of cinnamon oil against P. aeruginosa was tested, measured by the inhibition of biofilm formation and other QS-associated phenomena, including virulence factors such as pyocyanin, rhamnolipid, protease, alginate production, and swarming activity. To this end, multiple microscopy analyses, including light, scanning electron and confocal microscopy, revealed the ability of cinnamon oil to inhibit P. aeruginosa PAO1 biofilms and their accompanying extracellular polymeric substances. This work is the first to demonstrate that cinnamon oil can influence various QS-based phenomena in P. aeruginosa PAO1, including biofilm formation. 相似文献
100.
Christopher Leela Biji Manu K Madhu Vineetha Vishnu Satheesh Kumar K Vijayakumar Achuthsankar S Nair 《Bioinformation》2015,11(5):267-271
The big data storage is a challenge in a post genome era. Hence, there is a need for high performance computing solutions for
managing large genomic data. Therefore, it is of interest to describe a parallel-computing approach using message-passing library
for distributing the different compression stages in clusters. The genomic compression helps to reduce the on disk“foot print” of
large data volumes of sequences. This supports the computational infrastructure for a more efficient archiving. The approach was
shown to find utility in 21 Eukaryotic genomes using stratified sampling in this report. The method achieves an average of 6-fold
disk space reduction with three times better compression time than COMRAD.