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491.
David L. Goldstein James Frisbie Andrew Diller Ram Naresh Pandey Carissa M. Krane 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2010,180(8):1257-1265
Cope’s gray treefrogs, Hyla chrysoscelis, accumulate glycerol during the period of cold acclimation that leads to the development of freeze tolerance. Glycerol must
cross cell membranes in numerous processes during this time, including exit from hepatocytes where glycerol is synthesized
and entry into other tissues, where glycerol is cryoprotective. Thus, we hypothesized that erythrocytes from H. chrysoscelis would be permeable to glycerol and that that permeability would be up-regulated during cold acclimation. Further, we hypothesized
that glycerol permeability would be associated with the expression of aquaporins, particularly those from the glyceroporin
sub-family. Erythrocytes from warm-acclimated treefrogs had high glycerol permeability at 20°C, as assessed by the time required
for osmotic lysis following suspension in 0.2 M glycerol. That osmotic lysis, as well as uptake of radio-labeled glycerol,
was inhibited by 0.3 mM HgCl3. Permeability assessed via osmotic lysis was markedly reduced at 5°C. These properties were similar in animals deriving from
northern (Ohio) and southern (Alabama) populations, although suggestive (through statistical interactions) of greater glycerol
permeability in northern animals. Erythrocytes expressed mRNA and protein for a previously described glyceroporin, HC-3. In
cold-acclimated animals, HC-3 protein expression was up-regulated, but we could not detect a concomitant enhancement of glycerol
permeability. 相似文献
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Eugene M.H. Yee Eddy Pasquier George Iskander Kasey Wood David StC Black Naresh Kumar 《Bioorganic & medicinal chemistry》2013,21(7):1652-1660
Isoflavene–propranolol hybrid molecules were developed as potentially novel anti-tumour agents. Isoflavene itself has potent anti-cancer activity while propranolol can enhance anti-proliferative and anti-angiogenic properties of 5-fluorouracil and paclitaxel. The hybrids were produced via nucleophilic addition of substituted amine groups to a dioxiran intermediate, which was in turn generated from the Williamson-type reaction of isoflavene with (±)-epichlorohydrin. These analogues were tested in anti-cancer cell viability assays against SHEP neuroblastoma and MDA-MB-231 breast adenocarcinoma cell lines, and were found to exhibit potent anti-proliferative activities. These compounds also displayed anti-angiogenic and anti-proliferative effects in HMEC-1 human microvascular endothelial cell lines. Notably, the most potent hybrid molecules synthesized in this work showed enhanced potency against cancer cell lines compared to either isoflavene or propranolol alone, while retaining significant selectivity for cancer cells over MRC-5 normal lung fibroblast cells. 相似文献
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Application of electronic nose technology for the detection of fungal contamination in library paper 总被引:2,自引:0,他引:2
Olinda Canhoto Flavia Pinzari Corrado Fanelli Naresh Magan 《International biodeterioration & biodegradation》2004,54(4):303-309
Studies were carried out in vitro on a cellulose based agar at two water activities (aw,0.975,0.995) and on three types of paper at two relative humidities (75, 100% RH) for the potential for differentiation of contamination and colonisation by Aspergillus terreus, A. holandicus and Eurotium chevalieri. In vitro studies showed that conducting polymer sensor array gave different responses to each of these species when grown on cellulose agar at both aw levels. Discriminant function analyses of the data showed differentiation of the controls from the spoilage fungi. Cluster analysis gave a significant (P=0.05) separation of the control and each spoilage fungus. In situ studies on three types of paper showed that using natural substrates the volatile patterns produced by each of these fungi was different from each other and from the control. The results obtained were better at the higher humidity. The three paper types could be successfully differentiated into clusters. For a single paper type, differentiation of controls from spoilage fungal treatments was better at the higher humidity. This study has shown that this technology has potential for the early detection of fungal contamination in library materials and archives for the improved protection of cultural heritage. 相似文献
497.
Raina Jain Hemanta Adhikary Sanjay Jha Anamika Jha G. Naresh Kumar 《Microbial biotechnology》2012,5(6):764-772
Arsenite‐tolerant bacteria were isolated from an organic farm of Navsari Agricultural University (NAU), Gujarat, India (Latitude: 20°55′39.04″N; Longitude: 72°54′6.34″E). One of the isolates, NAU‐1 (aerobic, Gram‐positive, non‐motile, coccobacilli), was hyper‐tolerant to arsenite (AsIII, 23 mM) and arsenate (AsV, 180 mM). 16S rRNA gene of NAU‐1 was 99% similar to the 16S rRNA genes of Rhodococcus (Accession No. HQ659188). Assays confirmed the presence of membrane bound arsenite oxidase and cytoplasmic arsenate reductase in NAU‐1. Genes for arsenite transporters (arsB and ACR3(1)) and arsenite oxidase gene (aoxB) were confirmed by PCR. Arsenite oxidation and arsenite efflux genes help the bacteria to tolerate arsenite. Specific activities of antioxidant enzymes (catalase, ascorbate peroxidase, superoxide dismutase and glutathione S‐transferase) increased in dose‐dependent manner with arsenite, whereas glutathione reductase activity decreased with increase in AsIII concentration. Metabolic studies revealed that Rhodococcus NAU‐1 produces excess of gluconic and succinic acids, and also activities of glucose dehydrogenase, phosphoenol pyruvate carboxylase and isocitrate lyase were increased, to cope with the inhibited activities of glucose‐6‐phosphate dehydrogenase, pyruvate dehydrogenase and α‐ketoglutarate dehydrogenase enzymes respectively, in the presence of AsIII. Enzyme assays revealed the increase in direct oxidative and glyoxylate pathway in Rhodococcus NAU‐1 in the presence of AsIII. 相似文献
498.
Mridusmita Saikia Raul Jobava Marc Parisien Andrea Putnam Dawid Krokowski Xing-Huang Gao Bo-Jhih Guan Yiyuan Yuan Eckhard Jankowsky Zhaoyang Feng Guo-fu Hu Marianne Pusztai-Carey Madhavi Gorla Naresh Babu V. Sepuri Tao Pan Maria Hatzoglou 《Molecular and cellular biology》2014,34(13):2450-2463
Adaptation to changes in extracellular tonicity is essential for cell survival. However, severe or chronic hyperosmotic stress induces apoptosis, which involves cytochrome c (Cyt c) release from mitochondria and subsequent apoptosome formation. Here, we show that angiogenin-induced accumulation of tRNA halves (or tiRNAs) is accompanied by increased survival in hyperosmotically stressed mouse embryonic fibroblasts. Treatment of cells with angiogenin inhibits stress-induced formation of the apoptosome and increases the interaction of small RNAs with released Cyt c in a ribonucleoprotein (Cyt c-RNP) complex. Next-generation sequencing of RNA isolated from the Cyt c-RNP complex reveals that 20 tiRNAs are highly enriched in the Cyt c-RNP complex. Preferred components of this complex are 5′ and 3′ tiRNAs of specific isodecoders within a family of isoacceptors. We also demonstrate that Cyt c binds tiRNAs in vitro, and the pool of Cyt c-interacting RNAs binds tighter than individual tiRNAs. Finally, we show that angiogenin treatment of primary cortical neurons exposed to hyperosmotic stress also decreases apoptosis. Our findings reveal a connection between angiogenin-generated tiRNAs and cell survival in response to hyperosmotic stress and suggest a novel cellular complex involving Cyt c and tiRNAs that inhibits apoptosome formation and activity. 相似文献
499.
Sunil S. Metkar K. N. Naresh A. A. Redkar J. J. Nadkarni 《Cancer immunology, immunotherapy : CII》1998,47(2):104-112
Paclitaxel or Taxol has attracted a great deal of attention in recent years because of its immense success as a chemotherapeutic
agent for numerous types of cancer. It is known that paclitaxel stabilizes microtubules, and this characteristic is the presumed
primary mechanism for its antitumor activity. Recently, however, paclitaxel’s ability to regulate gene expression, particularly
in the murine system, has been reported by several groups. Here, we present research examining paclitaxel’s ability to alter
expression of the interleukin-1β (IL-1β) and IL-8 cytokines in primary human monocytes, T lymphocytes, and four human breast
cancer cell lines: MCF-7, ZR-75-1, MDA-MB-468, and MDA-MB-231. This report shows for the first time that treatment with 5–50
μM paclitaxel increases steady-state levels of IL-1β mRNA in unprimed human monocytes, MCF-7, and ZR-75-1 cells. Monocytes
from eight donors in 16 experiments showed increased IL-1β secretion upon treatment; however, the increase in IL-1β production
by monocytes was predicated on culturing in the absence of fetal bovine serum or in the presence of autologous human serum.
In contrast to the IL-1β results, paclitaxel did not have significant effects on IL-8 expression by monocytes, T lymphocytes,
or the breast cancer cells. These data show a specific effect of paclitaxel on cytokine synthesis by both immune cells and
cancer cells.
Received: 8 September 1997 / Accepted: 26 November 1997 相似文献
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