全文获取类型
收费全文 | 1144篇 |
免费 | 84篇 |
出版年
2021年 | 10篇 |
2020年 | 5篇 |
2019年 | 6篇 |
2018年 | 11篇 |
2017年 | 7篇 |
2016年 | 10篇 |
2015年 | 24篇 |
2014年 | 30篇 |
2013年 | 43篇 |
2012年 | 59篇 |
2011年 | 45篇 |
2010年 | 26篇 |
2009年 | 31篇 |
2008年 | 62篇 |
2007年 | 66篇 |
2006年 | 56篇 |
2005年 | 64篇 |
2004年 | 71篇 |
2003年 | 55篇 |
2002年 | 51篇 |
2001年 | 59篇 |
2000年 | 62篇 |
1999年 | 39篇 |
1998年 | 15篇 |
1997年 | 27篇 |
1996年 | 15篇 |
1995年 | 18篇 |
1994年 | 19篇 |
1993年 | 12篇 |
1992年 | 38篇 |
1991年 | 25篇 |
1990年 | 22篇 |
1989年 | 13篇 |
1988年 | 8篇 |
1987年 | 9篇 |
1986年 | 13篇 |
1985年 | 15篇 |
1984年 | 13篇 |
1983年 | 11篇 |
1982年 | 4篇 |
1981年 | 9篇 |
1980年 | 3篇 |
1979年 | 7篇 |
1977年 | 2篇 |
1975年 | 4篇 |
1974年 | 5篇 |
1973年 | 8篇 |
1971年 | 3篇 |
1970年 | 7篇 |
1969年 | 4篇 |
排序方式: 共有1228条查询结果,搜索用时 15 毫秒
11.
The role of liver endothelium in the binding and uptake of ceruloplasmin: studies with colloidal gold probe 总被引:6,自引:0,他引:6
To determine the mode of uptake of ceruloplasmin (CP) by liver, the protein was labeled with colloidal gold and infused into the portal vein. In cold almost all probes bound to the sinusoidal endothelium, and at 37 degrees C internalization via a system of coated pits and vesicles occurred. Only rarely did the probe appear to bypass the endothelium, moving to the abluminal side through the gaps between endothelial cells. In the endothelial cytoplasm, the probe was seen in coated vesicles, endosomes, tubules, and large vesicles which may have formed by fusion of endosomes and tubules. Moreover, externalization of the probe to the abluminal side was noted, and this also occurred via a system of coated vesicles. The findings suggest that the uptake of CP in the liver may be primarily a transendothelial phenomenon (transcytosis). 相似文献
12.
The present study was designed to examine the influence of delta 9-tetrahydrocannabinol (THC) on the central dopaminergic system using circling behavior. THC 5 mg/kg i.p. produced ipsilateral circling in rats with unilateral nigral lesion by 6-hydroxy-dopamine. THC-induced ipsilateral circling was completely antagonized by 0.2 mg/kg of haloperidol. These findings suggest that THC may cause a presynaptic stimulation of nigrostriatal dopaminergic neurons. 相似文献
13.
Prof. Katsuko Kataoka Junko Miura Yasuko Takeoka Yoshisuke Kusumoto Noboru Yanaihara 《Cell and tissue research》1985,239(3):531-535
Summary Ontogenesis of gastrin cells was studied in the pyloroduodenal mucosa of the mouse using anti-human G17 serum, R-1301, and anti-human G34(1–15) serum, R-2703. R-1301-immunostained cells first appeared in the pyloric mucosa of 14-day-old fetuses. Cells stained with both R-1301 and R-2703 appeared immediately after birth, and gradually increased in number to the adult level. Most R-1301-reactive cells were also reactive to R-2703, whereas some cells that reacted with R-1301 exhibited very weak or no reaction with R-2703. The discrepancy between these two immunoreactivities is discussed.In the duodenum, a considerable number of R-1301-reactive cells were present from the perinatal stage and through out adult development. A few R-2703-reactive cells were seen in the duodenum of young mice but not of the adult. 相似文献
14.
Summary Mice inoculated with both L1210 murine tumour vaccine and pyran copolymer were more resistant to L1210 than those inoculated with either of these agents alone. Rabbit anti-mouse thymocyte globulin and silica reduced the augmented resistance of these mice, suggesting the involvement of activated anti-tumour T cells and macrophages in the augmented resistance. We studied the activation of these two cells separately and examined the possible contribution of pyran copolymer-induced peritoneal cells to the augmented resistance to an inoculation of live tumour. Pyran copolymer-induced peritoneal cells endowed the tumour vaccine-primed mice, but not unprimed mice, with resistance to implanted L1210 and, among those peritoneal cell populations, macrophages but not T cells were responsible for this effect since the activity was associated with a cell population which was (1) adherent to nylon wool columns, (2) sensitive to silica and (3) insensitive to anti-Thy 1.2 antibody plus complement. The pyran copolymer-induced peritoneal cells had very little antiproliferative activity when tested against L1210 in vitro and mice inoculated with these peritoneal cells did not survive a challenge of live L1210 cells much longer (<1 day) than L1210 inoculated control mice. Furthermore, the survival of L1210 vaccine-primed mice inoculated with one-tenth the amount of live L1210 (102) was still much shorter than that of mice primed with L1210 vaccine plus pyran copolymer and challenged with ten times as many (103) live L1210 cells. Therefore, direct tumouricidal activity was probably not a major factor in the in vivo immunological augmenting activity of the pyran copolymer-induced macrophages. 相似文献
15.
Complete nucleotide sequences of all three poliovirus serotype genomes. Implication for genetic relationship, gene function and antigenic determinants 总被引:91,自引:0,他引:91
H Toyoda M Kohara Y Kataoka T Suganuma T Omata N Imura A Nomoto 《Journal of molecular biology》1984,174(4):561-585
The complete nucleotide sequences of the genomes of the type 2 ( P712 , Ch, 2ab ) and type 3 (Leon 12a1b ) poliovirus vaccine strains were determined. Comparison of the sequences with the previously established genome sequence of type 1 (LS-c, 2ab ) poliovirus vaccine strain revealed that 71% of the nucleotides in the genome RNAs were common, that the 5' and 3' termini of the genomes were highly homologous, and that more than 80% of the nucleotide differences in the coding region occurred in the third letter position of in-phase codons, resulting in a low frequency of amino acid difference. These results strongly suggested that the serotypes of poliovirus derived from a common prototype. A comparison of the amino acid sequences predicted from the genome sequences showed highest variation in the capsid protein region, whereas non-structural proteins are highly conserved. Initiation of polyprotein synthesis occurs in all three strains more than 740 nucleotides downstream from the 5' end. An analysis of the non-coding region suggests that small peptides that could potentially originate from this region are conserved. The amino acid sequences immediately surrounding the cleavage signals, however, show a higher than average degree of variation. The analysis of the amino acid sequences of the capsid protein VP1 of all serotypes has led to the prediction of potential antigenic sites on the virion involved in neutralization. 相似文献
16.
Hideki Ozawa Takao Iwaguchi Tateshi Kataoka 《Cancer immunology, immunotherapy : CII》1986,23(1):73-77
Summary Spleen cells of BALB/c mice hyperimmunized with a transplantable methylcholanthrene-induced sarcoma Meth A (Meth A-Im-SPL) inhibited the growth of Meth A tumor in vivo in a tumor neutralizing test. Meth A-Im-SPL did not neutralize another antienically distinct sarcoma, Meth 1, indicating that the antitumor activity is tumor specific. Lyt-1+2– cells of Meth A-Im-SPL (Im-Lyt-1+2–) were the effectors since in vitro treatment of Meth A-Im-SPL with anti-Thy 1.2 or anti-Lyt 1.2 antibody plus complement completely abrogated their neutralizing activity, whereas treatment with anti-Lyt 2.2 plus complement did not. To further confirm the effector activity of Im-Lyt-1+2– cells, T cell subpopulations were separated from Meth A-Im-SPL by the panning method. The purified Im-Lyt-1+2–, but not Im-Lyt-1+2+ cells neutralized the tumor in athymic nu/nu mice as efficiently as in +/+ mice, suggesting that the donor Im-Lyt-1+2– cells but not recipient T cells were primarily responsible for neutralizing the tumor. The present study, however, did not exclude the possible contribution of recipient T cells to the tumor neutralization and this is open to further investigation.Abbreviations Meth A-Im-SPL
Meth A-immune mouse spleen cells
- Meth 1-Im-SPL
Meth 1-immune mouse spleen cells
- sIg+ cells
surface immunoglobulin positive cells
- moAb
monoclonal antibody 相似文献
17.
Purification and properties of ovine cationic chymotrypsin 总被引:1,自引:0,他引:1
18.
A New Enzymatic Cycling Technique for Glutamate Determination in Brain Microdialysates 总被引:2,自引:1,他引:1
Akira Mitani Hirohiko Kubo Kouzo Iga Hitoshi Imon Fumito Kadoya Kiyoshi Kataoka 《Journal of neurochemistry》1990,54(2):709-711
A quantitative analysis of glutamate in brain dialysate was made by using an enzymatic cycling technique. This method made it possible to measure the concentration of glutamate in dialysate collected at 30-s intervals. Dialysates were collected from Mongolian gerbil hippocampus before, during, and after two 90-s ischemic insults at an interval of 5 min. An extracellular increase in levels of glutamate was already observed in samples collected during a 30-60 s period after the onset of each ischemia, and the levels of glutamate were maximal at the end of each period of ischemia (approximately a fourfold increase). The increased levels of glutamate rapidly returned almost to preischemic levels by 30 s of recirculation. This method will provide more precise information about temporal changes in the extracellular glutamate concentration in the brain during ischemia. 相似文献
19.
Hiroaki Kataoka Kazuki Nabeshima Naoto Komada Masashi Koono 《Virchows Archiv. B, Cell pathology including molecular pathology》1989,57(1):157-165
Two new human cell lines, RCM-1 and CoCM-1, have been established from primary colorectal adenocarcinomas. Both cell lines
were unique in that the cultures secreted trypsin inhibitors in vitro. The activities of these inhibitors were accumulated
in serum-free media of both cell lines over a period of several days. Two inhibitors (PI-1 and PI-2) were isolated from serum-free
conditioned medium in which RCM-1 was grown by anion-exchange and gel filtration high-performance liquid chromatography. PI-1
inhibited trypsin and chymotrypsin strongly, and pancreatic elastase weakly. Its molecular weight was about 57 kilodaltons
(Kd) as determined by gel filtration chromatography. It cross-reacted with the antiserum elicited against human α1-antitrypsin in double immunodiffusion. PI-1 corresponding to α1
- antitrypsin was also demonstrated immunohistochemically in both cell lines. PI-2 inhibited trypsin strongly, and chymotrypsin,
kallikrein and plasmin weakly. It had higher molecular weight (200–300 Kd) than that of PI-1, and did not crossreact with
antisera against human α1-antitrypsin, α2-macroglobulin, α1-antichymotrypsin, α2-plasmin inhibitor, inter-α-trypsin inhibitor and urinary trypsin inhibitor. RCM-1 and CoCM-1 are the first colorectal adenocarcinoma
cell lines that secrete functionally active trypsin inhibitors, including α1-antitrypsin in vitro, and are useful for the study of tumor-cell derived proteinase inhibitors. 相似文献
20.
T Kawano H Kataoka H Nagasawa A Isogai A Suzuki 《Biochemical and biophysical research communications》1992,189(1):221-226
We have identified the cDNAs encoding pheromone biosynthesis activating neuropeptide (PBAN) using PCR technique. The nucleotide sequence showed that the PBAN gene encodes, besides PBAN, diapause hormone and three putative amidated peptides. These four peptides share with PBAN the C-terminal pentapeptide amide which is corresponding to the shortest fragment with pheromonotropic activity. The organization of the PBAN gene is characteristic of several short neuropeptides and has some degree of similarity to that of the gene for the insect neuropeptide FMRFamide. Thus, the PBAN gene products construct a family of structurally related peptides and have various biological functions. 相似文献