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991.
Mizuta T Fujiwara M Abe T Miyano-Kurosaki N Yokota T Shigeta S Takaku H 《Biochemical and biophysical research communications》2000,279(1):158-161
The antiviral effects of a 20-mer antisense phosphorothioate oligonucleotide, PB2-as, on influenza A virus infection in mice were examined and compared to those of PB2-as encapsulated with several cationic liposomes. Intravenous injection of PB2-as, as a complex with DMRIE-C, a cationic liposome, was most effective for prolonging the mean survival time in days (MSDs) and increasing the survival rates of mice infected with the influenza A virus. In addition, the liposomal PB2-as significantly inhibited viral growth in lung tissues. These results suggest that PB2-as encapsulated with DMRIE-C may be active against the influenza A virus infection through the inhibition of virus replication in the mouse lung. 相似文献
992.
A potent inhibitor of inducible nitric oxide synthase, ONO-1714, a cyclic amidine derivative 总被引:6,自引:0,他引:6
Naka M Nanbu T Kobayashi K Kamanaka Y Komeno M Yanase R Fukutomi T Fujimura S Seo HG Fujiwara N Ohuchida S Suzuki K Kondo K Taniguchi N 《Biochemical and biophysical research communications》2000,270(2):663-667
(1S,5S,6R,7R)-7-Chloro-3-imino-5-methyl-2-azabicyclo[4.1.0]heptane hydrochloride (ONO-1714), a novel cyclic amidine analogue, inhibits human inducible nitric oxide (iNOS) with a K(i) of 1.88 nM and rodent iNOS with similar potency in vitro. ONO-1714 was found to be 10-fold selective for human iNOS over human endothelial NOS (ecNOS). When the inhibitory activity of ONO-1714 was compared for iNOS, it was found to be 451-fold and >20,000-fold more potent than L-NMMA and aminoguanidine (AG), respectively. In terms of human iNOS selectivity, ONO-1714 was approximately 34- and 2-fold more selective for iNOS than L-NMMA and AG, respectively. ONO-1714 inhibited the LPS-induced elevation of plasma nitrate/nitrite in mice with an ID(50) value of 0.010 mg/kg, s.c. The maximum tolerated dose of ONO-1714 was 30 mg/kg, i.v. Thus, ONO-1714 represents one of the most potent iNOS inhibitors in vitro and in vivo to date and has great potentials for use as an inhibitor for clarifying the pathophysiological roles of iNOS and for use as a therapeutic agent. 相似文献
993.
N Gotoh K Kambara X W Jiang M Ohno S Emura T Fujiwara H Fujiwara 《Journal of applied physiology》2000,88(2):518-526
We test the hypothesis that microvascular endothelial cells may undergo apoptosis in response to acute pulmonary venous hypertension. The isolated rabbit lungs were perfused in situ for 4 h with left atrial pressure of 0, 10, or 20 mmHg at a constant blood flow. Edema formation was monitored by lung weight gain. To assay for apoptosis, we performed agarose gel electrophoresis of DNA, in situ nick end labeling of DNA strand breaks, and electron microscopy. We also examined the levels of expression of Bcl-2, a suppressor of apoptosis, in microvascular endothelial cells using an immunohistochemical technique. In a vascular pressure-dependent fashion, we found apoptosis in endothelial cells of alveolar septal capillaries, as well as expression of Bcl-2 in arteriolar and venular endothelial cells. We conclude that acute pulmonary venous hypertension induces apoptosis in capillary endothelial cells but not in arteriolar and venular endothelial cells, suggesting that microvascular endothelial cell apoptosis is dependent on the levels of Bcl-2 expression and influences the formation or resolution of acute hydrostatic lung edema. 相似文献
994.
The end product of purine metabolism varies from species to species. The degradation of purines to urate is common to all
animal species, but the degradation of urate is much less complete in higher animals. The comparison of subcellular distribution,
intraperoxisomal localization forms, molecular structures, and some other properties of urate-degrading enzymes (urate oxidase,
allantoinase, and allantoicase) among animals is described. Liver urate oxidase (uricase) is located in the peroxisomes in
all animals with urate oxidase. On the basis of the comparison of intraperoxisomal localization forms, mol wt, and solubility
of liver urate oxidase among animals, it is suggested that amphibian urate oxidase is a transition form in the evolution of
aquatic animals to land animals. Allantoinase and allantoicase are different proteins in fish liver, but the two enzymes form
a complex in amphibian liver. The subcellular localization of allantoinase and allantoicase varies among fishes. Hepatic allantoinase
is located both in the peroxisomes and in the cytosol in saltwater fishes, and only in the cytosol in freshwater fishes. Hepatic
allantoicase is located on the outer surface of the, peroxisomal membrane in the mackerel group and in the peroxisomal matrix
in the sardine group. Amphibian hepatic allantoinase-allantoicase complex is probably located in the mitochondria. On the
basis of previous data, changes of allantoinase and allantoicase in molecular structure and intracellular localization during
animal evolution may be as follows: Fish liver allantoinase is a single peptide with a mol wt of 54,000, and is located both
in the peroxisomes and in the cytosol, or only in the cytosol. Fish liver allantoicase consists of two identical subunits
with a mol wt of 48,000, and is located in the peroxisomal matrix or on the outer surface of the peroxisomal membrane. The
evolution of fishes to amphibia resulted in the dissociation of allantoicase into subunits, and in the association of allantoinase
with the subunit of allantoicase. This amphibian enzyme was lost by further evolution. 相似文献
995.
Risk of premature birth in multifetal pregnancy. 总被引:1,自引:0,他引:1
The risk of preterm delivery (< 37 weeks of gestation) is approximately nine times higher in women with multifetal pregnancies than in women with singleton pregnancies. However, it is possible that the risk will vary according to gestational week. To assess the risk of premature birth within 1 week by gestational age among multifetal pregnancies and compare the estimated risk with that of singleton pregnancies, we analyzed 6,036,475 infants born in singleton pregnancies and 90,887 infants born in multifetal pregnancies in Japan (> or =22 weeks) over the 5-year period 1989-1993. An estimate of the risk of birth within 1 week at gestational week n was obtained by dividing the number of infants delivered at gestational week n by the number of infants delivered at or beyond gestational week n. The risk at 22 weeks was 0.9 per 1000 fetuses for singleton pregnancies and 5.0 per 1000 for multifetal pregnancies. The risk remained relatively stable until 27 weeks of gestation, then sharply increased toward 36 weeks of gestation in both singleton and multifetal pregnancies. The odds ratio for birth within 1 week for fetuses of multifetal pregnancies compared with fetuses of singleton pregnancies was 5.9 (95% CI, 5.4-6.5) at 22 weeks of gestation, increasing gradually with increasing gestational age until 33 weeks of gestation (13.7; 95% CI, 13.1-14.2) but declining thereafter to 8.8 (95% CI, 8.6-8.9) at 36 weeks of gestation. Results of data analysis for each year of the 5-year period did not differ substantially. 相似文献
996.
Jun Nakamura Akira Tetsukawa Shigeki Fujiwara 《Development, growth & differentiation》2015,57(1):58-67
Chondroitin sulfate (CS) is a carbohydrate component of proteoglycans. Several types of sulfotransferases determine the pattern of CS sulfation, and thus regulate the biological functions of proteoglycans. The protochordate ascidians are the closest relatives of vertebrates, but the functions of their sulfotransferases have not been investigated. Here, we show that two chondroitin 4‐O‐sulfotransferases (C4STs) play important roles in the embryonic morphogenesis of the ascidian Ciona intestinalis. Ci‐C4ST‐like1 is predominantly expressed in the epidermis and muscle. Epidermal and muscle cells became spherical upon the injection of a Ci‐C4ST‐like1‐specific morpholino oligo (MO), thus suggesting weakened cell adhesion. Co‐injection of a Ci‐C4ST‐like1‐expressing transgene rescued the phenotype, suggesting that the effects of the MO were specific. Ci‐C4ST‐like3 was expressed in the central nervous system, muscle, and mesenchyme. A specific MO appeared to affect cell adhesion in the epidermis and muscle. Convergent extension movement of notochordal cells was also impaired. Forced expression of Ci‐C4ST‐like3 restored normal morphogenesis, suggesting that the effects of the MO were specific. The present study suggests that Ci‐C4ST‐like1 and Ci‐C4ST‐like3 are required for cell adhesion mainly in the epidermis and muscle. 相似文献
997.
Limnology - We investigated the transfer of radiocesium and its behavior in living cells and cellular debris in a Chlamydomonas spp. bloom in a pond located approximately 5 km from the... 相似文献
998.
To investigate the central effect of neurotensin in gastric functions, changes in gastric acid secretion and mucosal blood flow (MBF) following administration were examined in rats anesthetized with urethane. Neurotensin in doses 1–10 μg/animal injected into the lateral ventricle decreased the basal value of both gastric acid output and MBF. This effect of neurotensin on these gastric parameters was completely blocked by pretreatment of animals with reserpine (2 mg/kg, i.p., 24 hr) or 6-OH-dopamine (250 μg/animal, intraventricularly, 10–14 days). These results indicate that exogenously applied neurotensin induces an inhibition of gastric functions by a central mechanism and suggest that an interaction exists between central catecholamines and the effect of neurotensin on gastric functions. 相似文献
999.
Induction of tumor-specific in vivo protective immunity by immunization with tumor antigen-pulsed antigen-presenting cells 总被引:4,自引:0,他引:4
J Shimizu T Suda T Yoshioka A Kosugi H Fujiwara T Hamaoka 《Journal of immunology (Baltimore, Md. : 1950)》1989,142(3):1053-1059
The present study investigates the role of APC in inducing tumor-specific in vivo protective immunity. Thy-1+ cell-depleted, Mac-1+ cell-enriched fraction of normal BALB/c spleen cells were used as a source of APC. These APC were cultured in vitro with the membrane fraction isolated from CSA1M fibrosarcoma derived from BALB/c strain. The administration of such APC into naive BALB/c mice generated the capacity of these animals to reject the subsequently challenged viable CSA1M tumor cells. Although the induction of anti-CSA1M in vivo protective immunity required three consecutive immunizations with more than 10(5) APC which had been pulsed in vitro with 200 to 300 micrograms protein of CSA1M membrane fraction, the immunity was induced irrespective of whether APC were administered via s.c., i.v., or i.p. route. This immunity was tumor-specific, inasmuch as the inoculation of CSA1M or Meth A fibrosarcoma membrane component-pulsed APC resulted in the selective immunity against the challenge with homologous types of tumor cells. The CSA1M-specific in vivo protective immunity was also induced by injecting APC pulsed with solubilized CSA1M membrane components. Moreover, it was demonstrated that the efficiency for inducing anti-CSA1M immunity was much higher in the utilization of tumor Ag-pulsed APC than in the immunization with tumor Ag emulsified in CFA. These results indicate the critical role of APC in generating tumor rejection immunity in vivo and this model presents a novel approach to induce tumor-specific immunity without using tumor cells themselves. 相似文献
1000.
Cellular aspects of tolerance. VII. Inheritance of the resistance to tolerance induction 总被引:1,自引:0,他引:1
The half-lives of elimination () of 131I-RGG from the body of normal A or Balb/c animals was much longer than the of SJL mice. At all ages, the of normal hybrids (A × SJL, SJL × A, Balb/c × SJL) was similar to or longer than that of the A or Balb/c parents. Thus, in terms of the of normal animals, the SJL responsiveness to 131I-RGG appeared to be a recessive trait. Tolerance could be induced in newborn animals and, in terms of , the degree of unresponsiveness at the age of 6 weeks, was the same in A, Balb/c, A × SJL, and Balb/c × SJL animals but was much shorter in SJL mice. Thus, in neonatally induced tolerance, the duration of tolerance was recessive for the SJL type. The average after tolerance induction in 3-week-old hybrids (A × SJL, SJL × A, Balb/c × SJL) was similar to that of the A or Balb/c parent, but by the 8th and 12th week it approached the average of the SJL parent. Comparing 8-week-old hybrids, the average was longest in A × SJL hybrids and identical in SJL × A and Balb/c × SJL mice. An examination of distribution in various 8- and 12-week-old crosses and backcrosses revealed a fairly large proportion of individuals with a which was intermediate between SJL and the other parent. There was a tendency for this number to decrease in 12 weeks as compared to 8-week-old mice. In 8-week-old mice, the number of animals with intermediate was smallest when SJL was the maternal animal [(SJL × A); SJL × (A × SJL); SJL × (SJL × A)]. There was no link between of tolerant animals and either the immunoglobulin allotype (MuAl/MuA2) or the C5 eniotype (MuB1 positive/MuB1 negative). 相似文献