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2.
Depending on the species, Cryptocoryne plants grow in different biotopes, viz. spring, river, dark forest, and tree-savanna. The species of Lagenandra are exclusively found in river biotopes. The chromosome numbers found in this study corroborate the numbers previously recorded. Some variation in respect to the morphology of the inflorescence of C. wendtii de Wit and L. ovata (L.) Thwaites is described. A map presenting the distribution of the of Cryptocoryne with their chromosome numbers is included.
The existing populations of Cryptocoryne on Sri Lanka should be protected from further exploitation by plant collectors. 相似文献
The existing populations of Cryptocoryne on Sri Lanka should be protected from further exploitation by plant collectors. 相似文献
3.
We describe the application of lamin immunocytochemistry (ICC) and single- or double-target fluorescence in situ hybridization (FISH) on 4 microm thick frozen tissue sections as a method to facilitate scoring of aberrant chromosome copy numbers in colonic tumors. Analysis of FISH signals in colon tissue sections is often hampered by overlap and truncation of epithelial nuclei, due to the density of the epithelial cells. Furthermore, on the basis of nuclear staining it is often difficult to determine whether or not nuclei are overlapping, or adjoining. Therefore, reliable evaluation of (F)ISH signals to screen for genomic changes was until now mainly restricted to isolated nuclei obtained from relatively thick tissue sections. In this study the applicability of lamin ICC, to stain the nuclear periphery and to distinguish individual nuclei, combined with the FISH procedure is explored to solve this problem for colon epithelium. For ICC we applied the alkaline phosphatase (APase)-Fast Red detection method, since the fluorescent precipitate of this reaction resists extensive proteolytic digestion as needed for efficient FISH on tissue sections. Chromosome copy numbers could easily be determined in 4 microm thick frozen tissue sections by combining lamin ICC and FISH. The ratio of the copy numbers of the chromosomes 7 and 17 could be determined in frozen tissue sections after combined lamin ICC and double-target FISH. It is concluded that the combination of lamin ICC and FISH improves chromosome copy number analysis and can be used to investigate genomic changes in different tumor compartments in thin frozen tissue sections. 相似文献
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5.
P Schauder C McIntosh J Arends R Arnold H Frerichs W Creutzfeldt 《Biochemical and biophysical research communications》1977,75(3):630-635
Somatostatin and insulin release from isolated rat pancreatic islets was stimulated by glucose, leucine or α-ketoisocaproic acid. D-glyceraldehyde stimulated insulin release but diminished the secretion of somatostatin. Glucagon and theophylline amplified the glucose-induced somatostatin release.A regulatory role of the D-cell's adenylate cyclase/phosphodiesterase system for the release of somatostatin is suggested. Furthermore, stimulation as well as inhibition of somatostatin release might be of significance for the secretory function of the B-cell. 相似文献
6.
Chromosome numbers for 38 species of Cryptocoryne are reported, 16 of which have not been reported earlier. About 90% of the species of Cryptocoryne have now been investigated cytologically. On the basis of chromosome numbers, morphology, and distribution, it is possible to distinguish some 24 groups within the species investigated. The chromosome numbers represent a heteroploid series which is based on the (secondary) base numbers 10, 11, 14, 15, 17, and 18. Evidence is given that 2n = 36 is the more primitive one. Evolution on the chromosome level has most likely gone in the direction of a reduction in numbers. Two new species, Cryptocoryne amicorum De Wit & N. Jacobsen and C. keei N. Jacobsen, are described. 相似文献
7.
Karin Müller Keri L.H. Carpenter Iain R. Challis Jeremy N. Skepper Mark J. Arends 《Free radical research》2013,47(7):791-802
Epidemiologically, a high-carotenoid intake via a fruit- and vegetable-rich diet is associated with a decreased risk of various forms of cancer. The mechanisms by which carotenoids exert this protective effect are controversial. In this study, we examined the potency of a range of carotenoids commonly found in human plasma to induce apoptosis in Jurkat E6.1 malignant T-lymphoblast cells. At a concentration of 20 w M, the order of potency to induce apoptosis after 24 h was: g -carotene > lycopene > lutein> g -cryptoxanthin=zeaxanthin. Canthaxanthin failed to induce apoptosis under these conditions. g -Carotene induced apoptosis in a time- and concentration-dependent manner with a lowest effective concentration of about 3 w M. Pre-conditioning of g -carotene for 72 h destroyed its pro-apoptotic activity almost completely, whereas degradation for 6 h or less did not, indicating that either g -carotene itself and/or an early degradation product of g -carotene are the death-inducing compounds. Apoptosis induced by g -carotene was characterized by chromatin condensation and nuclear fragmentation, DNA degradation, PARP cleavage and caspase-3 activation. The antioxidant BO-653 inhibited the degradation of g -carotene in vitro and significantly increased its cytotoxicity, indicating that a pro-oxidant effect of g -carotene is unlikely to cause its pro-apoptotic activity. The induction of apoptosis in transformed cells by carotenoids may explain their protective effect against cancer formation in humans. Possible pathways for induction of apoptosis by carotenoids are discussed. 相似文献
8.
This study was conducted to examine the psycho-emotional effects of repeated oral exposure to capsaicin, the principal active component of chili peppers. Each rat received 1 mL of 0.02% capsaicin into its oral cavity daily, and was subjected to behavioural tests following 10 daily administrations of capsaicin. Stereotypy counts and rostral grooming were significantly increased, and caudal grooming decreased, in capsaicin-treated rats during the ambulatory activity test. In elevated plus maze test, not only the time spent in open arms but also the percent arm entry into open arms was reduced in capsaicin-treated rats compared with control rats. In forced swim test, although swimming duration was decreased, struggling increased in the capsaicin group, immobility duration did not differ between the groups. Repeated oral capsaicin did not affect the basal levels of plasma corticosterone; however, the stress-induced elevation of plasma corticosterone was prolonged in capsaicin treated rats. Oral capsaicin exposure significantly increased c-Fos expression not only in the nucleus tractus of solitarius but also in the paraventricular nucleus. Results suggest that repeated oral exposure to capsaicin increases anxiety-like behaviours in rats, and dysfunction of the hypothalamic-pituitary-adrenal axis may play a role in its pathophysiology. 相似文献
9.
Tammi R. Duncan Atsushi Yahashiri S. J. Ryan Arends David L. Popham David S. Weiss 《Journal of bacteriology》2013,195(23):5308-5315
SPOR domains are about 75 amino acids long and probably bind septal peptidoglycan during cell division. We mutagenized 33 amino acids with surface-exposed side chains in the SPOR domain from an Escherichia coli cell division protein named FtsN. The mutant SPOR domains were fused to Tat-targeted green fluorescent protein (TTGFP) and tested for septal localization in live E. coli cells. Lesions at the following 5 residues reduced septal localization by a factor of 3 or more: Q251, S254, W283, R285, and I313. All of these residues map to a β-sheet in the published solution structure of FtsNSPOR. Three of the mutant proteins (Q251E, S254E, and R285A mutants) were purified and found to be defective in binding to peptidoglycan sacculi in a cosedimentation assay. These results match closely with results from a previous study of the SPOR domain from DamX, even though these two SPOR domains share <20% amino acid identity. Taken together, these findings support the proposal that SPOR domains localize by binding to septal peptidoglycan and imply that the binding site is associated with the β-sheet. We also show that FtsNSPOR contains a disulfide bond between β-sheet residues C252 and C312. The disulfide bond contributes to protein stability, cell division, and peptidoglycan binding. 相似文献
10.
Konrad Zych Yang Li Joeri K van der Velde Ronny VL Joosen Wilco Ligterink Ritsert C Jansen Danny Arends 《BMC bioinformatics》2015,16(1)