全文获取类型
收费全文 | 1290篇 |
免费 | 65篇 |
专业分类
1355篇 |
出版年
2023年 | 5篇 |
2022年 | 10篇 |
2021年 | 19篇 |
2020年 | 10篇 |
2019年 | 13篇 |
2018年 | 16篇 |
2017年 | 20篇 |
2016年 | 34篇 |
2015年 | 38篇 |
2014年 | 52篇 |
2013年 | 78篇 |
2012年 | 76篇 |
2011年 | 83篇 |
2010年 | 49篇 |
2009年 | 42篇 |
2008年 | 83篇 |
2007年 | 65篇 |
2006年 | 58篇 |
2005年 | 65篇 |
2004年 | 54篇 |
2003年 | 73篇 |
2002年 | 52篇 |
2001年 | 27篇 |
2000年 | 19篇 |
1999年 | 31篇 |
1998年 | 15篇 |
1997年 | 6篇 |
1996年 | 7篇 |
1995年 | 9篇 |
1994年 | 15篇 |
1993年 | 7篇 |
1992年 | 24篇 |
1991年 | 24篇 |
1990年 | 20篇 |
1989年 | 24篇 |
1988年 | 9篇 |
1987年 | 9篇 |
1986年 | 6篇 |
1985年 | 7篇 |
1984年 | 8篇 |
1979年 | 6篇 |
1978年 | 9篇 |
1976年 | 4篇 |
1975年 | 5篇 |
1973年 | 4篇 |
1972年 | 7篇 |
1970年 | 9篇 |
1969年 | 9篇 |
1968年 | 10篇 |
1967年 | 5篇 |
排序方式: 共有1355条查询结果,搜索用时 15 毫秒
1.
Yuji Inaba Yoshio Tanaka Sukemitsu Ishii Tomiaki Morimoto Kunihiko Sato Tuneyoshi Omori Minoru Matumoto 《Microbiology and immunology》1970,14(5):351-360
Replication of Ibaraki virus was not inhibited by 5-iodo-2′-deoxyuridine, indicating that the virus is an RNA virus. The virus was resistant to ether, chloroform and deoxycholate, sensitive to trypsin, very labile at acidic pH but stable at pH 6.4 or higher, and was resistant to repeated freezing and thawing. The virus was readily inactivated at 56 C or higher, was fairly stable at 37 C, and very stable at 4 C, while it rapidly lost infectivity when stored frozen at —20 C. The virus was readily sedimented by centrifugation at 40 000Xg for 60 min. It readily passed through membrane filters of 200 mμ pore size, passed through 100 μfilters but only with some titer loss and did not through 50 mμ filters. In these tests, the bluetongue virus used as a control behaved in the same manner as Ibaraki virus. These findings provide additional evidence for the similarity of Ibaraki virus to bluetongue virus which had been previously demonstrated on the basis of seasonal incidence, symptomatology and pathology of the diseases caused by these viruses and the behavior of the viruses in cell cultures, embryonated eggs and laboratory animals. The present study, however, provided no evidence for any serological relation between these two viruses. More Information is needed to reach a final decision on the classification of Ibaraki virus, particularly regarding the morphology of the virion, the doublestrandedness of the viral RNA and other basic features. 相似文献
2.
Tuneyoshi Omori Yuji Inaba Tomiaki Morimoto Yoshio Tanaka Hiroshi Kurogi Minoru Matumoto 《Microbiology and immunology》1967,11(2):133-142
Five strains of bovine diarrhea virus were isolated from Japanese cattle using bovine tissue cultures. These are the first isolations of this virus from Japanese cattle to be reported. Of importance is the finding that the new isolates, which are non-cytopathogenic, induce an exaltation of Newcastle disease virus in bovine testicular cell culture. This finding has provided a laboratory tool whereby the assay of the virus and its neutralizing antibody can readily be performed. 相似文献
3.
4.
S Katayama M Inaba Y Maruno A Omoto S Kawazu J Ishii M Sawada 《Prostaglandins, leukotrienes, and essential fatty acids》1990,39(1):47-51
The present study was designed to determine urinary excretion of kallikrein(KAL)-kinin as well as prostaglandin (PG) E2, TXB2 and 2,3-dinor-TXB2, a major urinary metabolite of TXA2 synthesized in platelets, by specific RIAs in patients with diabetes mellitus (DM). KAL or kinin excretion in 26 type II DM did not differ from control values obtained in 18 age-matched healthy subjects (C), although DM with HbA1 greater than 11% excreted less KAL. Urinary PGE2 excretion (7.6 +/- 2.8 ng/mg creatinine, mean +/- SE) was significantly lower in DM compared to C (17.5 +/- 3.9, p less than 0.05), while DM excreted more TXB2 (0.57 +/- 0.09, p less than 0.01) and 2,3-dinor-TXB2 (0.56 +/- 0.12, N.S.) than C (0.19 +/- 0.02 or 0.33 +/- 0.01). DM with or without mild proteinuria demonstrated lower PGE2, but higher TXB2 and 2,3-dinor-TXB2 excretion. A positive correlation of TXB2/2,3-dinor-TXB2 with proteinuria was observed in this group. However, in DM with massive proteinuria over 500 micrograms/mg creatinine, TXB2 and 2,3-dinor-TXB2 excretion decreased to levels almost identical to C. As a whole, a ratio of TXB2 to PGE2 or 2,3-dinor-TXB2 in DM was significantly higher than in C. The results suggest that a relative preponderance of TXB2 to 2,3-dinor-TXB2 may indicate an augmented renal, in addition to platelet, TXA2 synthesis. An excessive vasoconstrictive and proaggregatory TXA2 renal synthesis, concomitant with a decrease in vasodilatory and antiaggregatory PGE2, may have profound effects on renal functions such as protein excretion in DM. 相似文献
5.
Genomic organization, chromosomal localization, and independent expression of human cyclin D genes. 总被引:25,自引:0,他引:25
Murine cDNA clones for three cyclin D genes that are normally expressed during the G1 phase of the cell cycle were used to clone the cognate human genes. Bacteriophage and cosmid clones encompassing five independent genomic loci were partially sequenced and chromosomally assigned by an analysis of somatic cell hybrids containing different human chromosomes and by fluorescence in situ hybridization to metaphase spreads from normal peripheral blood lymphocytes. The human cyclin D1 gene (approved gene symbol, CCND1) was assigned to chromosome band 11q13, cyclin D2 (CCND2) to chromosome band 12p13, and cyclin D3 (CCND3) to chromosome band 6p21. Pseudogenes containing sequences related to cyclin D2 and cyclin D3 mapped to chromosome bands 11q13 and 6p21, respectively. Partial nucleotide sequence analysis of exons within each gene revealed that the authentic human cyclin D genes are more related to their mouse counterparts than to each other. These genes are ubiquitously transcribed in human tumor cell lines derived from different cell lineages, but are independently and, in many cases, redundantly expressed. The complex patterns of expression of individual cyclin D genes and their evolutionary conservation across species suggest that each family member may play a distinct role in cell cycle progression. 相似文献
6.
Induction by Electric Currents of Ethylene Biosynthesis in Cucumber (Cucumis sativus L.) Fruit 总被引:1,自引:1,他引:0
下载免费PDF全文
![点击此处可从《Plant physiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The effects of an electric current on ethylene biosynthesis were investigated in cucumber (Cucumis sativus L.) fruit that were producing almost no ethylene. Direct currents at 0.5 to 3.0 milliamperes induced much ethylene synthesis, with a rapid continuous increase in the rate, which reached a peak within 5 to 6 hours and then decreased. The rate of production was greater with a stronger current. Ethylene production was not observed after the use of a sine-wave alternating current (60 hertz) at 3 milliamperes, the magnitude at which a direct current had the greatest effect. The activity of 1-aminocyclopropane-1-carboxylic acid (ACC) synthase and ethylene forming enzyme (EFE) increased before the rise in ethylene production. ACC synthase and EFE were activated sixfold and fourfold, respectively, by 2 hours. The concentration of ACC increased linearly up to 6 hours and then decreased. Ethylene induction by an electric current was suppressed almost completely by the infiltration of the cucumbers with 5 millimolar aminooxyacetic acid, an inhibitor of ACC synthase, and was also suppressed 70% by 5 millimolar salicylic acid, an inhibitor of EFE. The results indicate that the ethylene induced by the direct current was synthesized via the ACC-ethylene pathway as a result of electrical stress, a new kind of stress to be identified. 相似文献
7.
M Kitaura T Kato K Inaba T Sakata Y Watanabe Y Kawade S Muramatsu 《Cellular immunology》1988,114(2):347-358
We investigated the regulation of class I and class II major histocompatibility complex (MHC) antigen expression of murine peritoneal macrophages (M phi) by interferons (IFNs) at the mRNA level. Enhancement of class I antigen expression by IFNs (IFN-alpha, beta, and gamma), induction of class II antigen expression by IFN-gamma, and inhibition of class II antigen expression by IFN-alpha or IFN-beta all corresponded to steady-state levels of these MHC-specific mRNAs. Cycloheximide (CHX), a protein synthesis inhibitor, was used to elucidate whether IFN regulation of MHC mRNA expression depends on the newly synthesized proteins. CHX concentration was carefully chosen so that M phi viability was not decreased, total protein synthesis was considerably but not completely inhibited, and suppression of surface class II expression was virtually perfect. Under these conditions CHX did not affect the levels of either class I or class II mRNA, but it prevented IFN-beta from interfering with class II mRNA induction by IFN-gamma. These results indicate that the augmentation of induction and/or accumulation of MHC mRNA by IFNs is not dependent on the de novo synthesis of protein, but the down-regulation of class II mRNA level by IFN-beta is mediated by some newly synthesized protein(s). 相似文献
8.
Erythrocyte membranes from goat contain a considerable amount, more than 10% of the total amount, of a glycoprotein with Mr = 155,000 (gp155) on sodium dodecyl sulfate-polyacrylamide electrophoresis gel. This report describes the first isolation and characterization of gp155. This gp155 has major trypsin-sensitive sites at each side of the plasma membrane to generate membrane-bound fragments, indicating that the gp155 spans the lipid bilayer several times. This protein consists of a single polypeptide containing about 1,200 amino acid residues corresponding to Mr = 134,000 and some complex type N-linked oligosaccharide chains. A fraction (15-20%) of the gp155 is recovered in nonionic detergent-extracted ghosts along with 25-30% of band 3 and other cytoskeletal proteins and is completely released into solution by extraction with 1 M KCl. Immunoprecipitation with anti-gp155 and anti-ankyrin antibodies of detergent-solubilized membranes separated on a gel permeation chromatography column showed that a part of the gp155 is tightly linked to band 3 with a molar ratio of 1:2 to 1:3. This gp155-band 3 complex in turn is associated to ankyrin through the binding of band 3 to ankyrin. These data indicate that, in native erythrocyte membranes, as well as in detergent solution, gp155 could play a physiological role in controlling cellular integrity and elasticity by forming the gp155-band 3-ankyrin complex. Partial amino acid sequences of the tryptic peptides are also determined. 相似文献
9.
M Inaba H Morii Y Nishizawa T Miki M Yukioka S Morisawa A Inoue 《Journal of biochemistry》1986,100(3):591-595
Calcitonin (CT) stimulated phosphorylation of two liver cytosolic proteins whose molecular weights are 67,000 and 93,000. Stimulation of 67,000-Mr protein phosphorylation began shortly after subcutaneous injection of CT, reaching a maximum at 5 min and decreasing to below the control level at 30 min. The reaction was independent of cyclic AMP or Ca2+, and was not influenced by a calmodulin antagonist, W7. Stimulation of 93,000-Mr protein phosphorylation became evident by 30 min. This reaction was also stimulated by administration of vasopressin or epinephrine, which is known to cause increased phosphorylation of glycogen phosphorylase having the same molecular weight. The phosphorylation of 93,000-Mr protein, stimulated by CT, was dependent on Ca2+ but not on cyclic AMP, and appeared to be inhibited by W7. In addition, CT did not influence the phosphorylation of 61,000-Mr protein, a major protein phosphorylated in a cyclic AMP-dependent manner. These results suggest that CT may exert its effect on liver cells through protein phosphorylation, most probably in a cyclic AMP-independent manner. 相似文献
10.
Yamamoto H.; Inaba S.; Nishiura Y.; Kishi F.; Kawakami Y. 《Journal of applied physiology》1985,58(3):717-723
Hypoxic and hypercapnic ventilatory responses were measured after two levels of acute inhalation of cigarette smoke, minimum-level nicotine smoke (smoke 1) and nicotine-containing smoke (smoke 2), in 10 normal men. Chemosensitivity to hypoxia and hypercapnia was assessed both in terms of slope factors for ventilation-alveolar PO2 curve (A) and ventilation-alveolar PCO2 line (S) and of absolute levels of minute ventilation (VE) at hypoxia or hypercapnia. Ventilatory response to hypoxia and absolute level of VE at hypoxia significantly increased from 23.5 +/- 22.6 (SD) to 38.6 +/- 31.3 l . min-1 . Torr and from 10.6 +/- 2.5 to 12.6 +/- 3.5 l . min-1, respectively, during inhalation of cigarette smoke 2 (P less than 0.05). Inhalation of cigarette smoke 2 tended to increase the ventilatory response to hypercapnia, and the absolute level of VE at hypercapnia rose from 1.42 +/- 0.75 to 1.65 +/- 0.58 l . min-1 . Torr-1 and from 23.7 +/- 4.9 to 25.5 +/- 5.9 l . min-1, respectively, but these changes did not attain significant levels. Cigarette smoke 2 inhalation induced an increase in heart rate from 64.7 +/- 5.7 to 66.4 +/- 6.3 beats . min-1 (P less than 0.05) during room air breathing, whereas resting ventilation and specific airway conductance did not change significantly. On the other hand, acute inhalation of cigarette smoke 1 changed none of these variables. These results indicate that hypoxic chemosensitivity is augmented after cigarette smoke and that nicotine is presumed to act on peripheral chemoreceptors. 相似文献