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21.
Balb/c mice were immunized with aluminium hydroxide [alum, Al(OH)3]-adjuvanted hepatitis B (HB) vaccines of subtypesadr,ayworadw. Spleen cells from the immune animals were fused with SP2/O cells. Eight hybridoma clones producing antibodies specific or HB surface antigen (HBsAg) were selected. Monoclonal antibodies (mAbs) of four clones were specific for group-specific antigen/a, and the other of four clones were specific for subtype antigen/d,y,r, orw. The anti-HBs/amAbs were classified into three non-competitive groups.Quantitation of group-specific determinantaof HBsAg (HBsAg/a) was performed by sandwich enzyme-linked immunosorbent assay (ELISA), in which a solid phase of anti-HBs guinea-pig polyclonal antibodies (pAb), the HBsAg for testing, anti-HBs/amouse mAb and horseradish peroxidase (HRP)-conjugated anti-mouse IgG were used.The unadsorbed HBsAg was used to establish the standard curve HBsAg/a. The lower detection limits were 0·5 to 1 ng/ml of HBsAg. Methods of solubilization of alum were investigated to quantify HBsAg/ain adsorbed HB vaccines. The recovery rate was more than 60% if vaccines were prediluted. The recovery of HBsAg/ain HB vaccines produced by the same manufacturer showed the similar recovery rate, and the contents of HBsAg/ain adsorbed HB vaccines could be estimated by the recovery rate determined for adsorbed HB vaccines.  相似文献   
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The purpose of this study was to establish a new technique for repeated oral administration to infant rats. To determine the maximum volume which could be administered to infant rats the following amounts of the Chinese ink were given by metal gastric zonde for mice: 0.01, 0.04 and 0.08ml/g B. W. General conditions and the arrival distance of the Chinese ink in the gastro-intestinal tract were also observed in infant rats. The best way of administration to infant rats was decided as follows: infant rats were isolated from the dums for one hour before administration and held tenderly by their neck to sustain their mouth upward, then a metal gastric zonde for mice 2 cm long was inserted to their mouth and drug solution was injected slowly. From the observation of general conditions and pathological examination, the maximum volumes for single or repeated administration were considered to be 0.04ml/g B. W. and 0.01 ml/g B. W. respectively. Daily oral administration of 0.1ml/g B. W. of distilled water, 1% CMC solution or 1% tragacantha gum suspension for 44 days caused no effects in infant rats when administration was begun 4 days after birth. These results show that the new method for administration to infant rats is useful to evaluate the toxicity or pharmacological activity of drugs.  相似文献   
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In this study, by use of technique that was modified from Morey method, we discussed the histological influence on the soleus muscle of the rats caused by disuse. This study is characterized by the calculating of total numbers of muscle fibers. ST (slow-twitch) and FT (fast-twitch) fibers in total muscular cross-sectional area were classified by their difference in intensity of staining of actomyosin adenosinetriphosphatase (myosin ATPase). During the experiment, average fiber diameter of ST and FT fibers declined when compared to control group (p less than 0.01). A 54% decrease in the total number of ST fibers was observed in the experimental group (p less than 0.01). Conversely, the total number of FT fibers increased to 362% of the control value (p less than 0.01). These results of the changes evoked in ST and FT fibers indicate 34% decrease in total muscular cross-sectional area, and showed that muscular function shifted toward a faster muscle in disused soleus muscle.  相似文献   
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Veillonellophage N2 prevented from adsorbing to Veillonella rodentium ATCC 17743 cells treated with polymyxin B, and also to lipopolysaccharides (LPSs) of the host cells treated with antibiotics. Therefore, these results indicate that receptor to phage N2 is cell wall LPSs. The LPSs of V. rodentium ATCC 17743 cells as receptor were characterized. Lipid A and total carbohydrate accounted for approximately 40% of the weight of the lipopolysaccharide complex. Heptose and 2-keto-3-deoxyoctonate were also present. Amino compounds included glucosamine, galactosamine, and glycine.  相似文献   
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A nuclear poly(A) polymerase has been isolated from oviducts of immature quails. It could be purified 4300-fold. The enzyme depends specifically on ATP as substrate and requires Mg2+. The most effective primer for the enzyme is a polynucleotide, isolated from oviduct tissue. A poly(A) sequence to a maximum of 60 AMP residues is covalently linked per primer molecule. The poly(A)-rich product of the enzymatic reaction can be annealed to oligo(dT)-cellulose. The purest fraction does not contain any detectable poly(A)-degrading enzyme activity. Only very low activities of RNA polymerase are present. The poly(A polymerase activity in the assay with ATP is reduced by the ATP analogue, beta, lambda-ATP-methylene-diphosphonate. Both K-m and V are lowered. The ATP analogue is incorporated to a smaller extent into the poly(A) sequence, synthesized by the enzyme. Several other analogues of adenine, adenine nucleosides and adenine nucleotides are without effect on the enzymatic reaction. By these properties poly(A) polymerase can be distinguished from RNA polymerases form I and form II, isolated from the same tissue. Actinomycin D and alpha-amanitin failed to inhibit poly(A) polymerase activity. The activity of poly(A) polymerase has been determined during primary stimulation with the estrogen analogue diethylstilbestrol (daily injection for 5 days), after withdrawal of the hormone for 17 days and after secondary stimulation with the hormone analogue. The enzyme activity does not change during primary stimulation, withdrawal of the hormone or secondary stimulation. However the activity of a poly(A) degrading enzyme, localized in the nucleus, is reduced in oviducts from hormone-treated quails.  相似文献   
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We previously reported that IL-7(-/-)RAG(-/-) mice receiving naive T cells failed to induce colitis. Such abrogation of colitis may be associated with not only incomplete T cell maintenance due to the lack of IL-7, but also with the induction of colitogenic CD4(+) T cell apoptosis at an early stage of colitis development. Moreover, NK cells may be associated with the suppression of pathogenic T cells in vivo, and they may induce apoptosis of CD4(+) T cells. To further investigate these roles of NK cells, RAG(-/-) and IL-7(-/-)RAG(-/-) mice that had received naive T cells were depleted of NK cells using anti-asialo GM1 and anti-NK1.1 Abs. NK cell depletion at an early stage, but not at a later stage during colitogenic effector memory T cell (T(EM)) development, resulted in exacerbated colitis in recipient mice even in the absence of IL-7. Increased CD44(+)CD62L(-) T(EM) and unique CD44(-)CD62L(-) T cell subsets were observed in the T cell-reconstituted RAG(-/-) recipients when NK cells were depleted, although Fas, DR5, and IL-7R expressions in this subset differed from those in the CD44(+)CD62L(-) T(EM) subset. NK cell characteristics were the same in the presence or absence of IL-7 in vitro and in vivo. These results suggest that NK cells suppress colitis severity in T cell-reconstituted RAG(-/-) and IL-7(-/-)RAG(-/-) recipient mice through targeting of colitogenic CD4(+)CD44(+)CD62L(-) T(EM) and, possibly, of the newly observed CD4(+)CD44(-)CD62L(-) subset present at the early stage of T cell development.  相似文献   
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The metabolism of vegetative organs in plants changes during the development of the reproductive organs. The regulation of this metabolism is important in the control of crop productivity. However, the complexity of the regulatory systems makes it difficult to elucidate their mechanisms. To examine these mechanisms, we constructed model experiments using Arabidopsis to analyze metabolic and gene expression changes during leaf-stage progression and after removal of the reproductive organs. Leaf gene expression levels and content of major amino acids, both of which decreased during leaf-stage progression, increased after removal of the reproductive organs. In particular, the levels of expression of cytokinin biosynthesis genes and cytokinin-responsive genes and the cytokinin content increased after removal of the reproductive organs. Analysis of plants with knockout of a cytokinin-biosynthetic gene (AtIPT3) and a cytokinin receptor gene (AHK3) indicated that glutamate dehydrogenase genes (GDH3) were regulated by cytokinin signaling. These data suggest that cytokinins regulate communication between reproductive and vegetative organs, and that GDH3 is one target of the cytokinin-mediated regulation of nitrogen metabolism. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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