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31.
A novel series of azobenzene isothiouronium salts of different alkyl chains (propyl, hexyl and dodecyl) were synthesized by reaction of 4-((4-methylphenyl)azo)phenol with 1,3-dibromopropane, 1,6-dibromohexane and 1,12-dibromododecane, respectively. These salts were reacted with copper (II) halide to give their corresponding metallo complexes. The surface tension measurements for the synthesized compounds show that the metallo complexes have adsorption and micellization better than that of the parent azobenzene isothiouronium salts. The pathogenic Gram-negative bacteria, Gram-positive bacteria, fungi and yeast were used to determine the biocidal activity of these compounds using gradient plate technique. The results indicate that the copper complexes of the synthesized azobenzene isothiouronium salts have a relatively better biocidal activity than the parent salts. 相似文献
32.
Five fluorouracil (5-FU) is extensively used in the treatment of hepatocellular carcinoma (HCC). It is well documented that
5-FU and its metabolites inhibit DNA synthesis through inhibition of thymidylate synthetase. Little is known about additional
pathways for 5-FU in managing HCC. The present experiment was mainly designed to study possible biochemical pathways that
can be added to 5-FU’s mechanisms of action. Four groups of rats constituted a control group (given saline only), a trichloroacetic
acid group (TCA, 0.5 g/kg/day for 5 days, orally), a 5-FU-positive group (75 mg/kg body weight, intraperitoneally, once weekly
for 3 weeks) and a TCA-treated with 5-FU group (24 h from last TCA dose). We executed both biochemical—serum alpha-fetoprotein
(AFP), liver tissue contents of total glycosaminoglycan (TGAGs), collagen (represented as hydroxyproline), total sialic acid
(TSA), free glucosamine (FGA) and proteolytic enzyme activity (as pepsin and free cathepsin-D—and histological examinations
of the liver tissue. The results revealed histological changes such as central vein congestion and irregularly shaped, substantially
enlarged, vesiculated and binucleated hepatocytes. The nuclei were mostly polymorphic and hyperchromatic, and several vacuolation
was noticed in the cytoplasm encircling the nucleus with masses of acidophilic material. 5-FU greatly corrected these changes,
except that some necrotic and cytotoxic effects of 5-FU were still shown. AFP was significantly elevated in TCA-intoxicated,
but reversed in 5-FU-treated, groups. Increased proteolytic activity by TCA was reversed by 5-FU, which also restored TGAG
contents to normal; but both TCA and 5-FU depleted collagen content. TCA significantly elevated FGA but depressed TSA; this
action was reversed by 5-FU treatment. In conclusion, it is possible that proteolytic activity, expressed as upregulated pepsin
and free cathepsin-D activities, is increased in HCC. This is accompanied by extracellular matrix macromolecular disturbance,
manifested as decreased TGAGs, collagen and TSA, with marked increase in FGA liver tissue content. The elevated FGA with depressed
TSA content of liver tissue may be attributed to a cancer-hampered N-acetylation of FGA into SA. 5-FU administration markedly depressed hepatic tissue proteolysis, possibly reactivated N-acetylation of FGA into SA and elevated TGAGs without stopping tissue fibrosis as collagen was not affected. This study explores
additional pathways for the mechanism of action of 5-FU, through conservation of extracellular matrix composition in situ,
inhibiting invasion and metastasis in addition to its DNA-disturbing pathway. 相似文献
33.
Respati T. Swasono Ryota Mouri Nagy Morsy Nobuaki Matsumori Tohru Oishi Michio Murata 《Bioorganic & medicinal chemistry letters》2010,20(7):2215-2218
The affinity of amphidinol 3 (AM3) to phospholipid membranes in the presence and absence of sterol was examined by surface plasmon resonance (SPR) experiments. The results showed that AM3 has 1000 and 5300 times higher affinity for cholesterol- and ergosterol-containing liposomes, respectively, than those without sterol. The two-state reaction model well reproduced the sensor grams, which indicated that the interaction is composed of two steps, which correspond to binding to the membrane and internalization to form stable complexes. 相似文献
34.
Modulation of TRPV1 by nonreceptor tyrosine kinase, c-Src kinase 总被引:5,自引:0,他引:5
Jin X Morsy N Winston J Pasricha PJ Garrett K Akbarali HI 《American journal of physiology. Cell physiology》2004,287(2):C558-C563
The capsaicin receptor TRPV1 is a nonselective cation channel that is expressed in sensory neurons. In this study, we examined the role of the nonreceptor cellular tyrosine kinase c-Src kinase in the modulation of the rat TRPV1. Capsaicin-induced currents in identified colonic dorsal root ganglion neurons were blocked by the c-Src kinase inhibitor PP2 and enhanced by the tyrosine phosphatase inhibitor sodium orthovandate. PP2 also abolished currents in human embryonic kidney-293 cells transfected with rat TRPV1, whereas cotransfection of TRPV1 with v-Src resulted in fivefold increase in capsaicin-induced currents. In cells transfected with dominant-negative c-Src and TRPV1, capsaicin-induced currents were decreased by approximately fourfold. TRPV1 co-immunoprecipitated with Src kinase and was tyrosine phosphorylated. These studies demonstrate that TRPV1 is a potential target for cellular tyrosine kinase-dependent phosphorylation. 相似文献
35.
Acceptor specificity of the human leukocyte alpha3 fucosyltransferase: role of FucT-VII in the generation of selectin ligands 总被引:2,自引:2,他引:0
Britten CJ; van den Eijnden DH; McDowell W; Kelly VA; Witham SJ; Edbrooke MR; Bird MI; de Vries T; Smithers N 《Glycobiology》1998,8(4):321-327
The alpha3 fucosyltransferase, FucT-VII, is one of the key
glycosyltransferases involved in the biosynthesis of the sialyl Lewis X
(sLex) antigen on human leukocytes. The sialyl Lewis X antigen
(NeuAcalpha(2-3)Galbeta(1-4)[Fucalpha(1-3)]GlcNAc-R) is an essential
component of the recruitment of leukocytes to sites of inflammation,
mediating the primary interaction between circulating leukocytes and
activated endothelium. In order to characterize the enzymatic properties of
the leukocyte alpha3 fucosyltransferase FucT-VII, the enzyme has been
expressed in Trichoplusia ni insect cells. The enzyme is capable of
synthesizing both sLexand sialyl-dimeric-Lexstructures in vitro , from
3'-sialyl-lacNAc and VIM-2 structures, respectively, with only low levels
of fucose transfer observed to neutral or 3'-sulfated acceptors. Studies
using fucosylated NeuAcalpha(2-3)-(Galbeta(1- 4)GlcNAc)3-Me acceptors
demonstrate that FucT-VII is able to synthesize both di-fucosylated and
tri-fucosylated structures from mono- fucosylated precursors, but
preferentially fucosylates the distal GlcNAc within a polylactosamine
chain. Furthermore, the rate of fucosylation of the internal GlcNAc
residues is reduced once fucose has been added to the distal GlcNAc. These
results indicate that FucT-VII is capable of generating complex selectin
ligands, in vitro , however the order of fucose addition to the lactosamine
chain affects the rate of selectin ligand synthesis.
相似文献
36.
David A Baldwin Deolinda MR de Sousa 《Biochemical and biophysical research communications》1981,99(4):1101-1107
The kinetics of iron release from N-terminal and C-terminal monoferric human transferrins has been studied using EDTA as the accepting chelate. In the absence of added salts iron release from the N-terminal site is more facile but the relative lability can be reversed by the addition of NaClO4, NaCl and LiCl. The results indicate that both anions and cations can affect the lability of the two sites. Since the relative lability of the two monoferrictransferrins is affected by fairly moderate concentrations of NaCl and NaClO4 we suggest that the ionic composition serum may play an important role in determining the observed distribution of iron among the sites. A new method for the preparation of N-terminal monoferrictransferrin is described. 相似文献
37.
Sianos G Kay IP Carlier SG Lighart JM Wardeh AJ Coen VL Levendag PC Serruys PW 《International journal of cardiovascular interventions》2000,3(2):121-125
The application of beta-radiation in coronary arteries is a promising new technique for the treatment of in-stent restenosis. This is the first case in which the 5 F. delivery catheter of the Beta-Cath trade mark system was advanced through the struts of a stent, previously deployed in an adjacent branch, so as to deliver radiation to the target vessel. 相似文献
38.
Assessment of losses in honey yield due to the chalkbrood disease, with reference to the determination of its economic injury levels in Egypt 总被引:2,自引:0,他引:2
Zaghloul OA Mourad AK El Kady MB Nemat FM Morsy ME 《Communications in agricultural and applied biological sciences》2005,70(4):703-714
In Egypt, the chalk brood (CHB) disease caused by the fungus, Ascosphaera apis Maassen started again infesting the honeybee, Apis melifera L (Hymenoptera: Apidae) colonies after a cessation pause of seven to nine years. For the first time, an attempt has been made to look into the problem of the CHB disease from the view point of assessing losses in both clover (Trifolium alexandrinum) and chinus (Chinus molus) honey yields. In this regard, two techniques were adopted. Under the natural conditions of the experimental apiary (first technique), loss in clover honey was 18.412 +/- 0.663%, on average, whereas the average loss in chinus honey was 18.332 +/- 1.536%. In the second technique of loss appraisal (artificial infection). The tested honeybee colonies were artificially infected with four sources of A. apis infection, I.e. black mummies, white mummies, pollen grains and water, in addition to controls to create the so-called "different levels of infection". The mean percentages of losses in clover honey were 30.06 +/- 1.807, 27.95 +/- 1.062; 21.13 +/- 0.987; 16.96 +/- 0.672 and 0.00 +/- 0.00 for black mummies, white mummies, pollen grains, water and control, respectively. Taking into account the relationship between number of resulted mummies in each source of infection and % loss in clover honey, it could be concluded that as the resulted mummies increased, the corresponding clover honey yield decreased in each source of infection. It was noticed that the % loss in clover honey differed as the used technique differed. For example, the percentage loss in clover honey produced from colonies exposed to the natural conditions was relatively less than that of the artificially infected ones. This has been discussed in the text. However, the causative pathogen of CHB disease resulted in serious decrease in honey production. Loss appraisal is a perquisite step for the determination of the economic injury levels (EILs). By regressing % loss in clover honey yield against the total number of fallen mummies, the linear equation was worked out to be: Y = 0.242 + 0.040 x (r2 = 0.99, F = 62408.865). Depending on the total costs of controlling CHB disease, the EIL values were 31.875 and 11.250 mummies/colony for cedar oil and thymol granules, subsequently. As to the chinus honey the corresponding EILs were 18.940 and 6.683 mummies/colony for cedar oil and thymol granules, in respect, as a result of adopting the regression formula: Y = -6.762 + 0.101 X. As for the clover honey (artificial infection) the EIL values were 39.844 and 14.063 mummies/ colony in case of using cedar oil and thymol grains, subsequently. These values were worked out using the formula Y = 5.871 + 0.032 X. From the practical point of view, apiarists should not use thymol or cedar oil as fallen mummies don't reach the suggested EILs values to minimize control costs as much as possible. 相似文献
39.
Jo?o?Luiz?S?Moreira Rodrigo?M?Mota Maria?F?Horta Santuza?MR?Teixeira Elisabeth?Neumann Jacques?R?Nicoli álvaro?C?NunesEmail author 《BMC microbiology》2005,5(1):15
Background
The accurate identification of Lactobacillus and other co-isolated bacteria during microbial ecological studies of ecosystems such as the human or animal intestinal tracts and food products is a hard task by phenotypic methods requiring additional tests such as protein and/or lipids profiling. 相似文献40.
The aim of this study is determining the different patterns of egg nests and the morphological differences between the specimens of Cicadatra persica Kirkalidy, 1909 (Hemiptera: Cicadidae) distributed in fruit orchards in Erneh located on AL-Sheikh mountain south west of Syria. The appearance of 80 egg nests was studied, and the results showed that there were two basic patterns of egg nests laid by Cicadatra persica, 90% of the egg nests were of the first pattern (consists of several adjacent slits), while 10% of them were of the second pattern (consists of several divergent slits). A random sample consisting of 300 specimens (150 males and 150 females) were also studied concentrating on the differences in the color of the supra-antennal plate and in the number of spurs on the tibia of the hind legs. The results showed that there were two basic patterns of individuals based on the differences in the color of supra-antennal plate. The first pattern (individuals with yellow supra-antennal plates), constituted more than 90%, and the second one (individuals with black supra-antennal plates) constituted less than 10%. The results also showed that there were 27 different patterns based on the number of spurs on the tibia of the hind legs. One of them was a common pattern (2, 3) whose individuals have 2 spurs on the upper side of the tibia of the hind legs and 3 spurs on the lateral side of the tibia of the hind legs. The total percent of this common pattern was 76%. The other 26 patterns were different from each other, and the total percent of all these different patterns was 24%. 相似文献