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991.
Mehmet E. Yalvac Mustafa Ramazanoglu Osman Z. Gumru Fikrettin Sahin András Palotás Albert A. Rizvanov 《Neurochemical research》2009,34(7):1272-1277
Introduction Human dental follicle cells (HDFCs) derived from human impacted third molars (wisdom teeth) have been shown to be a significant
source of adult stem cells. Generation of mesenchymal stem cell-like cells from dental follicles causes minimal surgical stress.
In vitro and in vivo reports showed that HDFCs can be utilized in gene and cell therapy applications which make them an attractive
alternative source for different gene-cell therapy applications. However, there are currently no systematic comparative studies
on transfection potential of HDFC cells using different chemical and electro-poration techniques. Methods Stem cells from impacted third tooth molars were isolated, and analyzed for expression of surface markers. Transfection efficiencies
of four commercially available transfection reagents (Transfast, Escort V, Superfect and FuGene HD) and electro-poration on
isolated stem cells were compared. Results Isolated HDFCs were stained positive for CD105, CD90, CD73, CD166, and negative for CD34, CD45, and CD133. Among the chemical
transfection reagents used in this study, FuGene HD was the most efficient in transfecting HDFCs, even in the presence of
10% serum. Conclusion Electro-poration of HDFCs yield relatively high transfection rates and cell viability when compared to chemical transfection
techniques. Our observations might be useful for developing gene and cell therapy applications using dental follicle stem
cells. 相似文献
992.
We present a robust and simple method for the direct detection of multiple point mutations in the Mycobacterium tuberculosis rpoB gene during the development of rifampin (RIF) resistance using an electrochemical genosensor. The device contained five different capture probes which are designed to hybridize with several sequence segments within the bacterial rpoB gene hotspot region. Point mutations were detected by monitoring the guanine oxidation with differential pulse voltammetry after hybridization between PCR amplicons and inosine modified capture probes at graphite surface. Changes in the peak voltage corresponding to guanine oxidation provide an electrochemical signal for hybridization that can be used to determine the presence of point mutations conferring rifampin resistance. The analytical parameters (sensitivity, selectivity and reproducibility) were evaluated. High selective discrimination against point mutation of bacteria at hot-spot region was observed. Several mutations were detected at several parts of the amplicon from 21 positive samples. 相似文献
993.
Mucin genes encode a family of the largest expressed proteins in the human genome. The proteins are highly substituted with O-linked oligosaccharides that greatly restrict access to the peptide backbones. The genomic organization of the N-terminal, O-glycosylated, and C-terminal regions of most of the mucins has been established and is available in the sequence databases. However, much less is known about the fate of their exposed protein regions after translation and secretion, and to date, detailed proteomic studies complementary to the genomic studies are rather limited. Using mucins isolated from cultured human airway epithelial cell secretions, trypsin digestion, and mass spectrometry, we investigated the proteome coverage of the mucins responsible for the maintenance and protection of the airway epithelia. Excluding the heavily glycosylated mucin domains, up to 85% coverage of the N-terminal region of the gel-forming mucins MUC5B and MUC5AC was achieved, and up to 60% of the C-terminal regions were covered, suggesting that more N- and sparsely O-glycosylated regions as well as possible other modifications are available at the C-terminus. All possible peptides from the cysteine-rich regions that interrupt the heavily glycosylated mucin domains were identified. Interestingly, 43 cleavage sites from 10 different domains of MUC5B and MUC5AC were identified, which possessed a non-tryptic cleavage site on the N-terminal end of the peptide, indicating potential exposure to proteolytic and/or "spontaneous cleavages". Some of these non-tryptic cleavages may be important for proper maturation of the molecule, before and/or after secretion. Most of the peptides identified from MUC16 were from the SEA region. Surprisingly, three peptides were clearly identified from its heavily glycosylated regions. Up to 25% coverage of MUC4 was achieved covering seven different domains of the molecule. All peptides from the MUC1 cytoplasmic domain were detected along with the three non-tryptic cleavages in the region. Only one peptide was identified from MUC20, which led us to successful antisera raised against the molecule. Taken together, this report represents our current efforts to dissect the complexities of mucin macromolecules. Identification of regions accessible to proteolysis can help in the design of effective antibodies and points to regions that might be available for mucin-protein interactions and identification of cleavage sites will enable understanding of their pre- and post-secretory processing in normal and disease environments. 相似文献
994.
995.
A quantitative trait locus for long photoperiod response mapped on chromosome 4H in barley 总被引:1,自引:0,他引:1
Xifeng Ren Chengdao Li Mehmet Cakir Wenying Zhang Christy Grime Xiao-Qi Zhang Sue Broughton Dongfa Sun Reg Lance 《Molecular breeding : new strategies in plant improvement》2012,30(2):1121-1130
Photoperiod response is a key determinant for barley adaptation to diverse environments. A major quantitative trait locus (QTL) for response to long photoperiod was identified in Australia (Perth, 31°56??S) and China (Wuhan, 30°33??N) using 178 doubled haploid lines derived from a cross of an Australian barley, Baudin, and a Canadian barley, AC Metcalfe. The QTL was detected as a major QTL in the 18-h photoperiod glasshouse experiments and mapped to the Xp12m50B199?CXp13m47B399 interval on chromosome 4H with a LOD score of 57 in Australia and confirmed in China. The single QTL accounted for 77.48 and 37.81% of phenotypic variation for long photoperiod response in Australia and China, respectively. The same QTL also controlled heading date in Australia, under normal and extended photoperiod conditions, and in China, under extended photoperiod and late-sown conditions. The QTL advanced heading date by 27.8?days in Australia and 42.5?days in China under a 18-h photoperiod. In addition, QTL for heading date were identified on chromosomes 2H and 3H. The chromosome 3H QTL was associated with the denso gene and detected in all conditions, but the chromosome 2H QTL was only detected in Australia. The new photoperiod response QTL, Qhea.BM.4-13/Qpho.BM.4-13, on chromosome 4H and its associated markers will provide an alternative for plant breeders developing new varieties for different environments using marker-assisted selection. 相似文献
996.
Ayvaz S Aksu B Kanter M Uzun H Erboga M Colak A Basaran UN Pul M 《Journal of molecular histology》2012,43(2):161-170
Myoglobinuric acute renal failure (ARF) is a uremic syndrome caused by traumatic or non-traumatic skeletal muscle breakdown
and intracellular elements that are released into the bloodstream. We hypothesized that hyperbaric oxygen (HBO) therapy could
be beneficial in the treatment of myoglobinuric ARF caused by rhabdomyolysis. A total of 32 rats were used in the study. The
rats were divided into four groups: control, control+hyperbaric oxygen (control+HBO), ARF, and ARF+hyperbaric oxygen (ARF+HBO).
Glycerol (8 ml/kg) was injected into the hind legs of each of the rats in ARF and ARF+HBO groups. 2.5 atmospheric absolute
HBO was applied to the rats in the control+HBO and ARF+HBO groups for 90 min on two consecutive days. Plasma urea, creatinine,
sodium, potassium, calcium, aspartate aminotransferase, alanine aminotransferase, lactic dehydrogenase, creatinine kinase
and urine creatinine and sodium were examined. Creatinine clearance and fractional sodium excretion could then be calculated.
Superoxide dismutase, catalase, glutathione and malondialdehyde (MDA) levels were assessed in renal tissue. Tissue samples
were evaluated by Hematoxylin-eosin, PCNA and TUNEL staining histopathologically. MDA levels were found to be significantly
decreased whereas SOD and CAT were twofold higher in the ARF+HBO group compared to the ARF group. Renal function tests were
ameliorated by HBO therapy. Semiquantitative evaluation of histopathological findings indicated that necrosis and cast formation
was decreased by HBO therapy and TUNEL staining showed that apoptosis was inhibited. PCNA staining showed that HBO therapy
did not increase regeneration. Ultimately, we conclude that, in accordance with our hypothesis, HBO could be beneficial in
the treatment of myoglobinuric ARF. 相似文献
997.
The aim of this study was to examine the preventive and therapeutic effects of thymoquinone (TQ) against cholestatic oxidative
stress and liver damage in common bile duct ligated rats. A total of 24 male Sprague–Dawley rats were divided into three groups:
control, bile duct ligation (BDL) and BDL + received TQ; each group contain 8 animals. The rats in TQ treated groups were
given TQ (50 mg/kg body weight) once a day orally for 2 weeks starting 3 days prior to BDL operation. To date, no more biochemical
and histopathological changes on common bile duct ligated rats by TQ treatment have been reported. The application of BDL
clearly increased the tissue hydroxyproline (HP) content, malondialdehyde (MDA) levels and decreased the antioxidant enzyme
[superoxide dismutase (SOD), glutathione peroxidase (GPx)] activities. TQ treatment significantly decreased the elevated tissue
HP content, and MDA levels and raised the reduced of SOD, and GPx enzymes in the tissues. The changes demonstrating the bile
duct proliferation and fibrosis in expanded portal tracts include the extension of proliferated bile ducts into lobules, mononuclear
cells, and neutrophil infiltration into the widened portal areas were observed in BDL group. Treatment of BDL with TQ attenuated
alterations in liver histology. The immunopositivity of alpha smooth muscle actin and proliferating cell nuclear antigen in
BDL were observed to be reduced with the TQ treatment. The present study demonstrates that oral administration of TQ in bile
duct ligated rats maintained antioxidant defenses and reduces liver oxidative damage and ductular proliferation. This effect
of TQ may be useful in the preservation of liver function in cholestasis. 相似文献
998.
1000.
Amyloid fibrils are β-sheet-rich protein aggregates commonly found in the organs and tissues of patients with various amyloid-associated diseases. Understanding the structural organization of amyloid fibrils can be beneficial for the search of drugs to successfully treat diseases associated with protein misfolding. The structure of insulin fibrils was characterized by deep ultraviolet resonance Raman (DUVRR) and Nuclear Magnetic Resonance (NMR) spectroscopy combined with hydrogen-deuterium exchange. The compositions of the fibril core and unordered parts were determined at single amino acid residue resolution. All three disulfide bonds of native insulin remained intact during the aggregation process, withstanding scrambling. Three out of four tyrosine residues were packed into the fibril core, and another aromatic amino acid, phenylalanine, was located in the unordered parts of insulin fibrils. In addition, using all-atom MD simulations, the disulfide bonds were confirmed to remain intact in the insulin dimer, which mimics the fibrillar form of insulin. 相似文献