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21.
Noriyuki Koibuchi Ryuichi Konno Shigeru Matsuzaki Hideki Ohtake Akira Niwa Sadao Yamaoka 《Histochemistry and cell biology》1995,104(5):349-355
d-Amino acid oxidase (DAO), which catalyzes oxidative deamination ofd-amino acids, is known to be highly expressed in the kidney. This study was designed to examine the localization of DAO mRNA in the mouse kidney using in situ hybridization histochemistry (ISH). For comparison, ISH for mRNA of ornithine decarboxylase (ODC), which is also highly expressed in the mouse kidney, was simultaneously performed. Adult, male mice which received 1 mg of testosterone propionate or vehicle injection, were sacrificed 14 h after injection and their kidneys were removed and processed for ISH. Hybridization signals for both mRNAs were exclusively located over the epithelial cells of the proximal tubule in the vehicle-treated animals. Signals for the DAO mRNA were observed at nearly the same hybridization intensity throughout the proximal tubule, whereas hybridization signals for the ODC mRNA were observed exclusively in the pars convoluta. Following testosterone treatment, ODC mRNA in the pars convoluta was expressed with a stronger intensity than that in the vehicle-injected animals. ODC mRNA was also expressed in the pars recta with a weaker intensity than in the pars convoluta. On the other hand, DAO mRNA expression was little affected by testosterone treatment. These results indicate that, although both genes are possibly expressed in the same cells, the expression of these genes is regulated by different mechanisms. 相似文献
22.
Laboratory matings were attempted to establish breeding colonies of red-backed voles (Clethrionomys rufocanus bedformidae) as experimental animals. For these mating, 10 pairs of red-backed voles which were captured in the Tohbetsu region of Hokkaido, Japan and their litters were used. In the results for two years, 1987 to 1988, the rates of pregnancy, birth and weaning were 35.4%, 94.5% and 79.5%, respectively. The mean litter size was 5:1 +/- 1.6 with a range of 1 to 9. The mean gestation period was 20.0 +/- 0.7 days with a range of 18 to 22. These results suggest that planned production of red-backed voles in the laboratory is possible. To determine intraregional variations of red-backed voles with a view to the establishment of a strain by inbreeding, restriction patterns of mitochondrial DNAs using seven restriction endonucleases were compared. Four different patterns were obtained from wild red-backed voles used in the present study. 相似文献
23.
Y Matsuzaki C Pannetien O Kanagawa G Gachelin H Nakauchi 《Journal of immunology (Baltimore, Md. : 1950)》1992,149(3):1069-1074
MRL mice homozygous for the lpr/lpr gene develop a massive lymphadenopathy caused by the accumulation of CD4-CD8-, Thy-1-positive T cells that express B220. This phenotypically unusual T cell population coexists with normal, B220- T cells in lpr/lpr animals. To investigate the origin and differentiation pathway of B220+ T cells, the expression of a panel of developmentally regulated cell surface markers including TCR, CD4, CD8, Thy-1, and B220 was examined. Thymocytes and peripheral T lymphocytes from lpr/lpr mice were analyzed by four-color flow cytometry. The results showed that both B220+ and B220- thymocytes contained all of CD4-CD8-, CD4+CD8+, and CD4 or CD8 single positive T cell subpopulation in the lpr thymus. Expression of the V beta 11 TCR, measured by flow cytometry and reverse polymerase chain reaction, was demonstrated in lpr thymus. However, the number of T cells expressing V beta 11 was greatly reduced in both the B220+ and B220- T cell populations in lymph node, spleen, and liver. Taken together, the data provide evidence for maturation and selection of a distinct population of B220+ T cells in the thymus of MRL lpr/lpr mice. 相似文献
24.
Chromosome engineering in Saccharomyces cerevisiae by using a site-specific recombination system of a yeast plasmid. 总被引:16,自引:0,他引:16 下载免费PDF全文
We have developed an effective method to delete or invert a chromosomal segment and to create reciprocal recombination between two nonhomologous chromosomes in Saccharomyces cerevisiae, using the site-specific recombination system of pSR1, a circular cryptic DNA plasmid resembling 2 microns DNA of S. cerevisiae but originating from another yeast, Zygosaccharomyces rouxii. A 2.1-kilobase-pair DNA fragment bearing the specific recombination site on the inverted repeats of pSR1 was inserted at target sites on a single or two different chromosomes of S. cerevisiae by using integrative vectors. The cells were then transformed with a plasmid bearing the R gene of pSR1, which encodes the site-specific recombination enzyme and is placed downstream of the GAL1 promoter. When the transformants were cultivated in galactose medium, the recombination enzyme produced by expression of the R gene created the modified chromosome(s) by recombination between two specific recombination sites inserted on the chromosome(s). 相似文献
25.
Structural evidence for two isozymic forms and the carbohydrate attachment site of human gastric cathepsin E 总被引:1,自引:0,他引:1
S B Athauda O Matsuzaki T Kageyama K Takahashi 《Biochemical and biophysical research communications》1990,168(2):878-885
The amino acid sequences in the NH2-terminal region and some other parts of human gastric cathepsin E were investigated. The NH2-terminal sequencing revealed that the cathepsin E preparation which had been activated at pH 4.0 contained one major and one minor isozymes in an approximate molar ratio of 3:1. The NH2-terminal sequence of the former was very similar to but partly different from that predicted from cDNA sequencing by Azuma et al., whereas the latter had an NH2-terminal sequence identical with the predicted sequence. These results provide structural evidence for the presence of at least two isozymic forms in human gastric cathepsin E. In addition, the site of carbohydrate attachment was elucidated by isolation and analysis of a glycopeptide fraction from an enzymatic digest of cathepsin E. A single carbohydrate chain was deduced to be attached to the asparagine residue at position 34 in the major isozyme and to the corresponding asparagine residue in the minor isozyme. 相似文献
26.
Localization by immunohistochemistry of renal ornithine decarboxylase in the mouse with and without testosterone treatment 总被引:1,自引:0,他引:1
The immunohistochemical distribution of renal ornithine decarboxylase was studied in male mice both with and without testosterone treatment. Testosterone (1 mg per mouse) induced a marked increase in ornithine decarboxylase activity of the mouse kidney, whereas no significant immunohistochemical difference was observed either in immunoreactivity or its localization. In intact male as well as androgen-treated mice dense ornithine decarboxylase-immunoreactive cells were observed mainly in the cortex, especially many ornithine decarboxylase-immunoreactive cells were observed in the inner portion, while a much weaker immunoreactivity was observed in the medulla. The largest number of ornithine decarboxylase-immunoreactive cells seemed to be localized in the pars recta of the proximal tubule. The immunoreactivity was not detected in all the tubular cells but scattered among them. The renal corpuscles were not immunoreactive. In each ornithine decarboxylase-immunoreactive cell, the cytoplasm showed much denser immunoreactivity than the nucleus. 相似文献
27.
H Sakata K Yamanouchi K Machida F Matsuzaki A Shishido H Iwashita Y Kuroiwa 《Japanese journal of medical science & biology》1979,32(2):67-76
A highly sensitive procedure of solid-phase radioimmunoassay (RIA) was developed for the detection of measles IgG antibody. HeLa cells persistently infected with measles virus were used as a solid-phase antigen. This technique was applied to the detection of measles IgG antibody in patients with subacute sclerosing panencephalitis (SSPE) and multiple sclerosis. Normal subjects having experienced natural measles or measles vaccination and patients with various neurological diseases of non-virus nature were also examined as control groups. Measles antibody was detected at high titers in both the sera and cerebrospinal fluid of SSPE patients. Moreover, RIA/HI ratios of SSPE patients were significantly higher than those of normal subjects, suggesting the presence in the formers of antibodies to nucleocapsids at high titers as well as to viral envelopes. On the other hand, no significant difference was found in both RIA and HI titers between the sera of multiple sclerosis and those of various neurological diseases. 相似文献
28.
S. Matsuzaki R. Pochet E. Schell-Frederick 《Biochimica et Biophysica Acta (BBA)/General Subjects》1973,313(2):329-337
The validity of 5′-nucleotidase as a plasma membrane marker enzyme in beef thyroid has been tested by comparing the subcellular distribution of its activity to that of (Na+K+)-activated ATPase and adenyl cyclase. The specific activity and total activity of (Na+K+)-ATPase and adenyl cyclase were greatest in the 1000 × g (“nuclear”) and 33 000 × g (“mitochondrial and lysosomal”) fractions. In contrast, 5′-nucleotidase activity was concentrated in the 165 000 × g (“microsomal”) pellet and supernatant. Partially purified plasma membranes were separated from the 1000 (N2), 30 000 (M2) and 165 000 × g (P2) pellets by discontinuous sucrose gradient centrifugation. Again a discordant distribution of these enzyme activities was observed. (Na+K+)-ATPase specific activity was increased approximately 30-fold over the homogenate in Fractions N2 and M2. Basal, thyroid-stimulating hormone-and fluoride-stimulated adenyl cyclase activities were concentrated in the same fractions. 5′-Nucleotidase activity was preferentially located in M2 and P2. These differences in distribution pattern suggest that 5′-nucleotidase activity is not uniquely located in the plasma membrane in the thyroid. 相似文献
29.
Kazuyo Yasuda Toshihiko Torigoe Rena Morita Takahumi Kuroda Akari Takahashi Junichi Matsuzaki Vitaly Kochin Hiroko Asanuma Tadashi Hasegawa Tsuyoshi Saito Yoshihiko Hirohashi Noriyuki Sato 《PloS one》2013,8(8)
Cancer stem-like cells (CSCs)/cancer-initiaiting cells (CICs) are defined as a small population of cancer cells that have self-renewal capacity, differentiation potential and high tumor-initiating ability. CSCs/CICs of ovarian cancer have been isolated by side population (SP) analysis, ALDEFLUOR assay and using cell surface markers. However, these approaches are not definitive markers for CSCs/CICs, and it is necessary to refine recent methods for identifying more highly purified CSCs/CICs. In this study, we analyzed SP cells and aldehyde dehydrogenese bright (ALDHBr) cells from ovarian cancer cells. Both SP cells and ALDHBr cells exhibited higher tumor-initiating ability and higher expression level of a stem cell marker, sex determining region Y-box 2 (SOX2), than those of main population (MP) cells and ALDHLow cells, respectively. We analyzed an SP and ALDHBr overlapping population (SP/ALDHBr), and the SP/ALDHBr population exhibited higher tumor-initiating ability than that of SP cells or ALDHBr cells, enabling initiation of tumor with as few as 102 cells. Furthermore, SP/ADLHBr population showed higher sphere-forming ability, cisplatin resistance, adipocyte differentiation ability and expression of SOX2 than those of SP/ALDHLow, MP/ALDHBr and MP/ALDHLow cells. Gene knockdown of SOX2 suppressed the tumor-initiation of ovarian cancer cells. An SP/ALDHBr population was detected in several gynecological cancer cells with ratios of 0.1% for HEC—1 endometrioid adenocarcinoma cells to 1% for MCAS ovary mucinous adenocarcinoma cells. Taken together, use of the SP and ALDHBr overlapping population is a promising approach to isolate highly purified CSCs/CICs and SOX2 might be a novel functional marker for ovarian CSCs/CICs. 相似文献
30.