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101.
    
Tnr1 is a repetitive sequence in rice with several features characteristic of a transposable DNA element. Its copy number was estimated to be about 3500 per haploid genome by slot-blot hybridization. We have isolated six members of Tnr1 located at different loci by PCR (polymerase chain reaction) and determined their nucleotide sequences. The Tnr1 elements were similar in size and highly homologous (about 85%) to the Tnr1 sequence identified first in the Waxy gene in Oryza glaberrima. A consensus sequence of 235 by could be derived from the nucleotide sequences of all the Tnr1 members. The consensus sequence showed that base substitutions occurred frequently in Tnr1 by transition, and that Tnr1 has terminal inverted repeat sequences of 75 bp. Almost all the chromosomal sequences that flank the Tnr1 members were 5-PuTA-3 and 5-TAPy-3, indicating that Tnr1 transposed to 5-PuTAPy-3 sites, duplicating the TA sequence. PCR-amplified fragments from some rice species did not contain the Tnr1 members at corresponding loci. Comparison of nucleotide sequences of the fragments with or without a Tnr1 member confirmed preferential transposition of Tnr1 to 5-PuTAPy-3 sites, duplicating the TA sequence. One amplified sequence suggested that imprecise excision had occurred to remove a DNA segment containing a Tnr1 member and its neighboring sequences at the Waxy locus of rice species with genome types other than AA. We also present data that may suggest that Tnr1 is a defective form of an autonomous transposable element.  相似文献   
102.
School-age children with high lipoprotein(a) [Lp(a)] levels were screened and family studies were conducted to examine the relationship between high Lp(a) levels and apolipoprotein(a) [apo(a)] isoforms in families. All the probands from 17 families had one of the A2 to A12 apo(a) isoforms, which are the smaller apo(a) isoforms of the 25 different isoforms thus far detected. The ratio of subjects with high plasma Lp(a) levels was 0.47 among the first-degree relatives. All 15 relatives with high plasma Lp(a) levels shared one of the small apo(a) isoforms with the proband in each family, while 16 of 17 relatives with normal Lp(a) levels did not. These data indicate the frequent occurrence of familial aggregations of high Lp(a) levels associated with one of the small apo(a) isoforms.  相似文献   
103.
We have developed a sensitve, high-resolution method for the analysis of the apolipoprotein(a) [apo(a)] isoforms using sodium dodecyl sulfate (SDS)-agarose/ gradient polyacrylamide gel electrophoresis. In an analysis of the genetic polymorphism of apo(a) isoforms and their relationship with plasma lipoprotein(a) [Lp(a)] levels in Japanese and Chinese, this method identified 25 different apo(a) isoforms and detected one or two apo(a) isoforms in more than 99.5% of the individuals tested. The apparent molecular weights of the apo(a) isoforms ranged from 370 kDa to 950 kDa, and 22 of the 25 different apo(a) isoforns had a higher molecular weight than of apo B-100. Studies on Japanese families confirmed the autosomal codominant segregation of apo(a) isoforms and the existence of a null allele at the apo(a) locus. The observed frequency distribution of apo(a) isoform phenotypes fit the expectations of the Hardy-Weinberg equilibrium in both the Japanese and Chinese populations. Our data indicate the existence of at least 26 alleles, including a null allele, at the apo(a) locus. The frequency distribution patterns of the apo(a) isoform alleles in Japanese and Chinese were similar to each other and also similar to that of apo(a) gene sizes reported in Caucasian American individuals. The average heterozygosity at the apo(a) locus was 92% in Japanese and 93% in Chinese. A highly significant inverse correlation was observed between plasma Lp(a) levels and the size of apo(a) isoforms in both the Japanese (r=-0.677, P=0.0001) and the Chinese (r=-0.703, P=0.0001). A highly skewed distribution of Lp(a) concentrations towards lower levels in the Japanese population may be explained by high frequencies of alleles encoding large apo(a) isoforms and the null allele.  相似文献   
104.
Following the subcutaneous administration of estriol-6,7-3H to rats, biliary metabolites were identified and quantitated. Approximately 70% of the metabolites were excreted in the form of “glucosiduronate” conjugates. 3, 17β-Dihydroxy-2-methoxy-1,3,5(10)-estratrien-16-one was the major metabolite in this conjugate fraction. Significant amounts of 3,17β-dihydroxy-1,3,5(10)-estratrien-16-one and 2,3,17β-trihydroxy-1,3,5(10)-estratrien-16-one, as well as smaller quantities of 1,3,5(10)-estratriene-2,3,16α,17β-tetrol and 2-methoxy-1,3,5(10)-estratriene-3,16α, 17β-triol, were also found. In 17α-ethinylestradiol - treated animals, the rate of excretion of radioactivity and the proportion of 16-oxo-17β-ol metabolites found in the “glucosiduronate” fraction were reduced.  相似文献   
105.
Asplenium sect. Thamnopteris or A. nidus L. complex is defined by the synapomorphic character peculiar to Aspleniaceae, an anastomosing vein near the margin of the simple lamina. Thus, it is easily recognizable and its monophyly is quite clear. In spite of its naturalness as the whole group, species delimitation is very confusing. Three species of sect. Thamnopteris, A. antiquum Makino, A. australasicum (J. Smith) Hooker and A. nidus L. have been recognized in Japan, but the naturalness of each species is still not clear because their morphology is too simple to find good qualitative taxonomical characters. In the present work, we examined the intraspecific variation of allozymes and rbcL sequences in the Japanese plants of sect. Thamnopteris and compared them with those from other paleotropical localities in order to recognize natural units in such morphologically simple plants. We found a large amount of genetic variation in this section and inferred that A. antiquum is a species of ancient origin, though morphologically it is not so different from other species of the sect. Thamnopteris. It was also discovered that the so called “A. australasicum” in Japan has a very different rbcL sequence from A. australasicum sensu Holttum, which is distributed in Australia and South Pacific Islands. Based on these molecular data, we described the Japanese “A. australasicum” as a new species, Asplenium setoi N. Murak. et Seriz. Received 9 September 1998/ Accepted in revised form 22 December 1998  相似文献   
106.
Abstract The role of the lipoamino acids (serratamolide and ornithine lipid), membrane lipid components of Serratia marcescens , was examined in phagocytosis and phagosome-lysosome fusion of human peripheral polymorphonuclear leukocytes. A mutant strain of Serratia marcescens (NS 38-09) lacking serratamolide was actively phagocytosed by human PMN, while the wild-type strain (NS 38) producing serratamolide was more resistant to phagocytosis by human PMN. Phagocytosis of killed Staphylococcus aureus coated with lipoamino acid (serratamolide), showed that they were more resistant to phagocytosis by PMN, while the cells coated with ornithine lipid or serratamic acid were phagocytosed more actively. Staphylococci coated with phosphatidylethanolamine or phosphatidylglycerol had no significant effect on phagocytosis by PMN. Phagosome-lysosome fusion by PMN labelled with acridine orange was examined by fluorescence microscopy. The fusion indices of lipoamino acid-coated staphylococci were the same as that of controls. Further, ornithine lipid-coated staphylococci stimulated the release of superoxide anion from PMN slightly, but serratamolide did not. These results suggested that serratamolide may contribute to the virulence of S. marcescens in vitro.  相似文献   
107.
Synthetic antimicrobial 9-mer peptides were designed from the amino acid sequence of an active site of insect defensin to increase the number of positively charged amino acid residues. These peptides, RLRLRIGRR-NH2, RLLLRIGRR-NH2 and RLYLRIGRR-NH2, showed strong antimicrobial activity against bacteria and fungus. These peptides showed no growth inhibition activity against murine fibroblasts or macrophages and no hemolytic activity against rabbit erythrocytes in vitro. Furthermore, the administration of these peptides protected mice from a lethal methicillin-resistant Staphylococcus aureus (MRSA) challenge. In addition, these peptides suppressed tumor necrosis factor alpha (TNF-alpha) gene expression and production induced by lipopolysaccharide (LPS) or lipoteichoic acid (LTA) in murine macrophages.  相似文献   
108.
Advanced glycation end-products (AGEs) are formed over several weeks to months by non-enzymatic glycation and oxidation (“glycoxidation”) reactions between carbohydrate-derived carbonyl groups and protein amino groups, known as the Maillard reaction. Pentosidine is one of the best-characterized AGEs and is accepted as a satisfactory marker for glycoxidation in vivo. The present study was intended to measure pentosidine concentrations in umbilical cord blood from newborns with various gestational ages using our recently established high-performance liquid chromatography method [Tsukahara, H. et al. (2003) Pediatr. Res. 54, 419-424]. Our study demonstrates, for the first time, that pentosidine is detected in most of the umbilical blood samples. This study also shows that the umbilical blood concentrations of pentosidine are considerably lower than normal adult values, but that they increase with gestation progression and fetal growth. Umbilical pentosidine concentrations were significantly elevated in newborns of mothers with preeclampsia compared to those of mothers without preeclampsia. We conclude that accumulation of AGEs and oxidative stress occurs in fetal tissues and organs in utero at the early stage of human life and that their accumulation is augmented in the maternal preeclampsic condition.  相似文献   
109.
Of the rice species with an AA genome, Oryza meridionalis has been identified in northern Australia as a species of the annual type, among those previously classified as Oryza perennis, Oryza rufipogon or Oryza nivara. This notion has, however, led to some confusion to determine which strains belong to O. meridionalis and how different these strains are from the O. rufipogon strains of the annual type. In this paper, we examined Australian wild rice strains for the presence or absence of p-SINE1 members, which have been used for identification of the strains of species with the AA genome, by PCR using primers that hybridize to the sequences flanking each p-SINE1 member. The rice strains examined include perennial and annual strains, which have previously been described as O. rufipogon. We found that all the annual strains and other strains, whose types have not been determined, have p-SINE1 members that are specifically present at the corresponding loci in the standard strains of O. meridionalis, but do not have those which are specifically present at the corresponding loci in the strains of the other species with the AA genome. The perennial strains, however, have p-SINE1 members that are specifically present at the corresponding loci in the standard O. rufipogon strains of either the annual or the perennial type, but do not have those which are specifically present at the corresponding loci in the strains of the other species with the AA genome, including O. meridionalis. These findings support the previous notion that O. meridionalis consists of the annual strains and is a distinct species from O. rufipogon. The p-SINE1 members used in this study appear to be very useful for classification of any wild rice strains of the AA-genome species, even when one has limited knowledge of morphology, taxonomy, physiology, and biochemistry of rice strains.  相似文献   
110.
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