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1.
Extracts of Prunella vulgaris have been shown to exert antiestrogenic effects. To identify the compounds responsible for these actions, we isolated the constituents of P. vulgaris and tested their individual antiestrogenic effects. Rosmarinic acid, caffeic acid, ursolic acid (UA), oleanolic acid, hyperoside, rutin and betulinic acid (BA) were isolated from the flower stalks of P. vulgaris var. lilacina Nakai (Labiatae). Among these constituents, UA and BA showed significant antiestrogenic effects, measured as a decrease in the mRNA level of GREB1, an estrogen-responsive protein; the effects of BA were stronger than those of UA. UA and BA were capable of suppressing estrogen response element (ERE)-dependent luciferase activity and expression of estrogen-responsive genes in response to exposure to estradiol, further supporting the suppressive role of these compounds in estrogen-induced signaling. However, neither UA nor BA was capable of suppressing estrogen signaling in cells ectopically overexpressing estrogen receptor α (ERα). Furthermore, both mRNA and protein levels of ERα were reduced by treatment with UA or BA, suggesting that UA and BA inhibit estrogen signaling by suppressing the expression of ERα. Interestingly, both compounds enhanced prostate-specific antigen promoter activity. Collectively, these findings demonstrate that UA and BA are responsible for the antiestrogenic effects of P. vulgaris and suggest their potential use as therapeutic agents against estrogen-dependent tumors.  相似文献   
2.
By nature of their segmented RNA genome, influenza A viruses (IAVs) have the potential to generate variants through a reassortment process. The influenza nonstructural (NS) gene is critical for a virus to counteract the antiviral responses of the host. Therefore, a newly acquired NS segment potentially determines the replication efficiency of the reassortant virus in a range of different hosts. In addition, the C-terminal PDZ-binding motif (PBM) has been suggested as a pathogenic determinant of IAVs. To gauge the pandemic potential from human and avian IAV reassortment, we assessed the replication properties of NS-reassorted viruses in cultured cells and in the lungs of mice and determined their transmissibility in guinea pigs. Compared with the recombinant A/Korea/01/2009 virus (rK09; 2009 pandemic H1N1 strain), the rK09/VN:NS virus, in which the NS gene was adopted from the A/Vietnam/1203/2004 virus (a human isolate of the highly pathogenic avian influenza H5N1 virus strains), exhibited attenuated virulence and reduced transmissibility. However, the rK09/VN:NS-PBM virus, harboring the PBM in the C-terminus of the NS1 protein, recovered the attenuated virulence of the rK09/VN:NS virus. In a guinea pig model, the rK09/VN:NS-PBM virus showed even greater transmission efficiency than the rK/09 virus. These results suggest that the PBM in the NS1 protein may determine viral persistence in the human and avian IAV interface.  相似文献   
3.
A Gram-negative, strictly aerobic, reddish-pink pigmented, motile, spherical, agar-degrading bacterium designated 06SJR6-2T was isolated from a green coloured marine alga (Cladophora sp.). Phylogenetic analyses based on the 16S rRNA gene sequence indicated that the new strain was affiliated with the class Phycisphaerae and shared 89.2 % sequence similarity with Phycisphaera mikurensis FYK2301M01T, which is the only validly named member of the class Phycisphaerae. The strain could be differentiated phenotypically from the recognised member of the class Phycisphaerae. The major fatty acids of strain 06SJR6-2T were identified as C16:0, C18:1ω9c and anteiso-C15:0. Amino acid analysis of cell wall hydrolysates indicated that the novel isolate did not contain diaminopimelic acid in the cell wall. The DNA G+C content of the strain was determined to be 63.0 mol% and the major respiratory quinone was identified as menaquinone 6 (MK-6). From the distinct phylogenetic position and combination of genotypic and phenotypic characteristics, the strain is considered to represent a novel genus in the family Phycisphaeraceae, for which the name Algisphaera agarilytica gen. nov., sp. nov. is proposed. The type strain of A. agarilytica is 06SJR6-2T (=KCTC 32482T = NBRC 109894T).  相似文献   
4.
I Jang  K Jung  J Cho 《Experimental Animals》1998,47(4):247-252
The present study was designed to determine age-related changes in intestinal and hepatic antioxidant enzymes including superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), and glutathione-S-transferase (GST), and lipid peroxidation in male Wistar rats (n = 8) aged 2 wk, 2.5 mon, 5 mon, 10 mon, and 23 mon. In the small intestine, cytosolic SOD, GSH-PX activities and lipid peroxidation were not affected by age, but intestinal GST activity was noticeably enhanced as age increased. In particular, intestinal GST activity in 23 mon old rats was 3 times as strong as that in 2 wk old rats. In the liver, the activity of hepatic cytosolic SOD was not affected by age, whereas GSH-PX and GST activities in rats aged 10 mon and 23 mon were much stronger than those in rats aged 2 wk, 2.5 mon, and 5 mon. The increased lipid peroxidation in 2.5 mon and 5 mon old rats was observed when compared with that of other groups. It is therefore concluded from the results presented here that age greatly increases GST activity in the small intestinal mucosae and increasing GSH-PX, GST activities and lipid peroxidation in the liver from male Wistar rats.  相似文献   
5.
Behavioral responses of adult female oriental fruit flies, Dacus dorsalisHendel, to the odor of papayas from three ripeness classes were studied using a threechoice flight tunnel bioassay. Laboratoryreared flies were allowed to respond freely to any of three papaya odors (mature green, colorbreak to one-fourth ripe, and one-half to full ripe) emanating from identical (spherical) fruit models. Five behaviors were measured in assessing the fly's relative attraction to the odors (number of landings), arrestment (total fly seconds on sphere), fly-fly interactions on the fruit model (maximum and modal fly density), and acceptance for oviposition (total eggs laid). Females showed no significant difference in total fly landings based on all age classes combined. Significant differences were noted among age classes. Females spent more total time on the sphere and showed a higher maximum density and modal fly density to ripe fruit than to green fruit odors. Ovipositional acceptance of fruit models based on the total number of eggs laid in a sphere was greater in response to the ripefruit odor than to the other two odor classes. Olfactorystimulated behavioral responses of females to the odor of ripe papayas were significantly different from the other ripeness classes for all behaviors at 8 days postemergence and then declined in 11-day-old flies. Behavioral responses were greater during the afternoon than in the morning. Observations of wild oriental fruit flies to papayas in the field indicated a preference for residing on riper fruit. The results of this study are discussed with regard to the role of olfactory inputs generated by the odor of ripening fruit on female attraction and oviposition behavior resulting in infestation of papayas by oriental fruit fly.  相似文献   
6.
7.
The purpose of this study is to assess health-related quality of life in polio survivors (PS) compared with that in the general population in Korea. Polio survivors (n = 120) from outpatient clinics at two hospitals, healthy controls (HC, n = 121) and members of the general population with activity limitations (AL, n = 121) recruited through a proportional-allocation, systematic sampling strategy from the Fourth Korean National Health and Nutrition Examination Survey were surveyed with self-rated health-related quality of life (Euro QoL five-dimensions). The proportion of participants who reported problems in mobility, usual activity, and symptoms of anxiety/depression were higher in the PS group compared with the HC and AL groups. There was no significant difference in the self-care dimension across the groups. Polio-specific questionnaire, pain, depression, fatigue, Modified Barthel Index (K-MBI) and Short Physical Performance Battery (SPPB) were assessed in the PS group. Those with post-poliomyelitis syndrome had greater problems in mobility, usual activity, and depression/anxiety. Polio survivors, especially those with more pain and fatigue symptoms, and those who did not have access to medical services had poorer health-related quality of life. These findings afford useful information for potential intervention improving quality of life in polio survivors.  相似文献   
8.
Tumor-associated macrophages (TAMs) are involved in tumor progression by promoting epithelial-mesenchymal transition (EMT), tumor cell invasion, migration and angiogenesis. However, in breast cancer, the clinical relevance of the TAM infiltration according to distinct histologic locations (intratumoral vs. stromal) and hormone receptor status is unclear. We investigated the significance of the levels of TAM infiltration in distinct histologic locations in invasive breast cancer. We also examined the relationship of the TAM levels with the clinicopathologic features of tumors, expression of EMT markers, and clinical outcomes. Finally, we analyzed the prognostic value of TAM levels according to hormone receptor status. High levels of infiltration of intratumoral, stromal and total TAMs were associated with high histologic grade, p53 overexpression, high Ki-67 proliferation index and negative hormone receptor status. Infiltration of TAMs was also correlated with overexpression of vimentin, smooth muscle actin and alteration of β-catenin. Overall, a high level of infiltration of intratumoral TAMs was associated with poor disease-free survival, and was found to be an independent prognostic factor. In subgroup analyses by hormone receptor status, a high level of infiltration of intratumoral TAM was an independent prognostic factor in the hormone receptor-positive subgroup, but not in the hormone-receptor negative subgroup. Our findings suggest that intratumoral TAMs play an important role in tumor progression in breast cancer, especially in the hormone receptor-positive group, and the level of TAM infiltration may be used as a prognostic factor and even a therapeutic target in breast cancer.  相似文献   
9.
The present study elucidated the effects of indoleamines (serotonin, melatonin, and tryptophan) on oxidative damage of brain mitochondria and synaptosomes induced either by 6-hydroxydopamine (6-OHDA) or by iron plus ascorbate and on viability loss in dopamine-treated PC12 cells. Serotonin (1-100 microM), melatonin (100 microM), and antioxidant enzymes attenuated the effects of 6-OHDA, iron plus ascorbate, or 1-methyl-4-phenylpyridinium on mitochondrial swelling and membrane potential formation. Serotonin and melatonin decreased the attenuation of synaptosomal Ca(2+) uptake induced by either 6-OHDA alone or iron plus ascorbate. Serotonin and melatonin inhibited the production of reactive oxygen species, formation of malondialdehyde and carbonyls, and thiol oxidation in mitochondria and synaptosomes and decreased degradation of 2-deoxy-D-ribose. Unlike serotonin, melatonin did not reduce the iron plus ascorbate-induced thiol oxidation. Tryptophan decreased thiol oxidation and 2-deoxy-D-ribose degradation but did not inhibit the production of reactive oxygen species and formation of oxidation products in the brain tissues. Serotonin and melatonin attenuated the dopamine-induced viability loss, including apoptosis, in PC12 cells. The results suggest that serotonin may attenuate the oxidative damage of mitochondria and synaptosomes and the dopamine-induced viability loss in PC12 cells by a decomposing action on reactive oxygen species and inhibition of thiol oxidation and shows the effect comparable to melatonin. Serotonin may show a prominent protective effect on the iron-mediated neuronal damage.  相似文献   
10.
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