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21.
HAX-1 protein, an anti-apoptotic factor, first identified in 1997, is also involved in cell migration, endocytosis and probably mRNA transport. HAX-1 structure indicates similarity to the proteins form Bcl-2 family, although there is no strong homology. HAX-1 is a substrate for Omi/HtrA2, a protease responsible for degradation of the caspases, and functions as an inhibitor of caspase-9, which points to its role in the regulation of apoptosis. Several HAX-1 interactions with proteins involved in apoptosis and cell motility were demonstrated. Another line of inquiry focus on its ability to bind 3' untranslated regions of the certain mRNAs. Some data indicate that it might be involved in mRNA transport. HAX-1 multifunctionality and its involvement in the processes important for the cell status suggest its possible role in oncogenesis and metastasis. It is also known that HAX-1 deficiency or overexpression leads to hereditary or systemic diseases (Kostmann disease, lesional psoriasis, systemic sclerosis). Therefore, detailed analysis of HAX-1 functions could be medically important. 相似文献
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Wlodzimierz Borejsza-Wysocki Ewa Borejsza-Wysocka Geza Hrazdina 《Plant cell reports》1997,16(5):304-309
Cell suspension cultures were established from germinating pea (Pisum sativum L.) seeds. This cell culture, which accumulated pisatin, consisted mostly of single cells containing a few cell aggregates. The cells responded to treatment with a yeast glucan preparation with transient accumulation of pisatin in both cells and culture media. Addition of pisatin to cell cultures resulted in increased synthesis of pisatin. Phenylalanine ammonia-lyase, chalcone synthase and isoflavone reductase activities were present in untreated cells. Upon treatment with an elicitor preparation the activities of the first two enzymes showed a rapid, transient increase up to 20 hours after treatment. Isoflavone reductase showed a major and minor peak at 16 and 36 h, respectively, after elicitor treatment. The time course of the enzyme activity and pisatin accumulation is consistent with an elicitor-mediated response.Abbreviations CHS
chalcone synthase
- 2,4-D
2,4-dichlorophenoxyacetic acid
- IBA
indole-3-butyric acid
- IFR
isoflavone reductase
- 2iP
6-(dimethylallylamino)-purine
- MS
Murashige & Skoog basal salt medium
- PAL
phenylalanine ammonia-lyase
- PMSF
phenylmethylsulfonyl fluoride
- POPOP
1,4-bis-2-(4-methyl-5-phenyloxazolyl)-benzene
- PPO
2,5-diphenyloxazole 相似文献
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Magdalena Chelchowska Jadwiga Ambroszkiewicz Katarzyna Jablonka-Salach Joanna Gajewska Tomasz M. Maciejewski Ewa Bulska Teresa Laskowska-Klita Jerzy Leibschang 《Biological trace element research》2013,155(2):169-175
To assess the effect of lead exposure from cigarette smoke on fetal growth, blood lead concentrations were measured using inductively coupled plasma mass spectrometry in 150 healthy pregnant women. Mean lead concentrations in plasma and whole blood were significantly higher in the smoking group compared with the nonsmoking group in each trimester of pregnancy (p?<?0.001). Logistic regression analysis showed the highest impact of the number of cigarettes smoked per day for serum lead concentration (β?=?0.238; p?<?0.05), while in whole blood, it was duration of smoking before conception (β?=?0.297; p?<?0.001). Birth weight of the smoking mothers' infants was significantly lower (mean?±?SEM, 3,192?±?50.8 and 3,569?±?49.6 g, respectively; p?<?0.001) and negatively correlated with lead levels in plasma (r?=??0.38; p?<?0.001) and in whole blood (r?=??0.27; p?<?0.001). Therefore, it is suggested that smoking during pregnancy increases lead concentrations in maternal blood. Fetal exposure to low doses of lead in utero may be a serious risk factor causing lower birth weight. 相似文献
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Paluchowska MH Bugno R Duszyńska B Tatarczyńska E Nikiforuk A Lenda T Chojnacka-Wójcik E 《Bioorganic & medicinal chemistry》2007,15(22):7116-7125
New, flexible (7, 9, 11 and 13) and rigid (8, 10, 12 and 14) imides with a 1-(m-trifluorophenyl)piperazine fragment and a tetramethylene or a 1e,4e-cyclohexylene spacer, respectively, showed very high affinity (K(i)=0.3-34 nM) and agonistic in vivo activity for 5-HT(1A) receptors. Flexible new compounds and the previously described 5 also bound to 5-HT(7) receptors (K(i)=21-134 nM). Selected glutarimide derivatives, that is, the most potent postsynaptic 5-HT(1A) receptor agonist rigid compound 8 and its flexible analogue 7, as well as the previously described full agonist-rigid compound 6 and the partial agonist-its flexible counterpart 5 exhibited moderate affinity for alpha(1)-adrenoceptors (K(i)=85 - 268 nM), but were practically devoid of any affinity for dopamine D(2) sites. Those glutarimides demonstrated anxiolytic- (5 and 7) and antidepressant-like (5, 6 and 8) activity in the four-plate and the swim tests in mice, respectively; at the same time, however, they inhibited the locomotor activity of mice. The antidepressant-like effect of 8 was significantly stronger than that induced by imipramine used as a reference antidepressant. 相似文献
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Ultraviolet radiation triggers apoptosis of fibroblasts and skin keratinocytes mainly via the BH3-only protein Noxa 下载免费PDF全文
To identify the mechanisms of ultraviolet radiation (UVR)-induced cell death, for which the tumor suppressor p53 is essential, we have analyzed mouse embryonic fibroblasts (MEFs) and keratinocytes in mouse skin that have specific apoptotic pathways blocked genetically. Blocking the death receptor pathway provided no protection to MEFs, whereas UVR-induced apoptosis was potently inhibited by Bcl-2 overexpression, implicating the mitochondrial pathway. Indeed, Bcl-2 overexpression boosted cell survival more than p53 loss, revealing a p53-independent pathway controlled by the Bcl-2 family. Analysis of primary MEFs lacking individual members of its BH3-only subfamily identified major initiating roles for the p53 targets Noxa and Puma. In the transformed derivatives, where Puma, unexpectedly, was not induced by UVR, Noxa had the dominant role and Bim a minor role. Furthermore, loss of Noxa suppressed the formation of apoptotic keratinocytes in the skin of UV-irradiated mice. Collectively, these results demonstrate that UVR activates the Bcl-2-regulated apoptotic pathway predominantly through activation of Noxa and, depending on cellular context, Puma. 相似文献
28.
Ewa?Chwe?atiuk Tadeusz?W?ostowskiEmail author Alicja?Krasowska Elzbieta?Bonda 《Biometals》2005,18(3):283-291
Recent study has shown that a short photoperiod increases the accumulation and toxicity of cadmium (Cd) in the bank vole as compared to a long photoperiod. Since many of the effects of photoperiod on physiological processes in small mammals are transduced by the pineal gland and its hormone melatonin, in this study the effect of subchronic melatonin injection (7 mol/kg/day for 6 weeks) on the hepatic, renal and intestinal Cd accumulation in the bank voles raised under a long photoperiod and exposed to dietary Cd (0.9 mol/g) was examined. Simultaneously, histological examinations of the liver and kidneys, and analyses of metallothionein (MT) and lipid peroxidation were carried out. Melatonin co-treatment brought about a significant increase in the hepatic (61%), renal (79%) and intestinal (77%) Cd concentrations as compared to those in the Cd alone group. However, the concentrations of MT in the liver and kidneys of the Cd + melatonin co-treated bank voles did not differ from those in the Cd alone group. Also, histopathological changes in the liver (infiltration of leukocytes) and kidneys (glomerular swelling and a focal tubular cell degeneration) as well as an increase (2-fold) in the renal lipid peroxidation occurred only in animals from the Cd + melatonin group. These data indicate that (1) subchronic melatonin injection has similar effect on the tissue accumulation and toxicity of Cd to that produced by a short photoperiod and (2) the Cd-induced toxicity in the liver and kidneys of melatonin co-treated bank voles is probably due to increased Cd accumulation and decreased synthesis of MT. 相似文献
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