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151.
Lithium metal anodes are expected to drive practical applications that require high energy‐density storage. However, the direct use of metallic lithium causes safety concerns, low rate capabilities, and poor cycling performance due to unstable solid electrolyte interphase (SEI) and undesired lithium dendrite growth. To address these issues, a radio frequency sputtered graphite‐SiO2 ultrathin bilayer on a Li metal chips is demonstrated, for the first time, as an effective SEI layer. This leads to a dendrite free uniform Li deposition to achieve a stable voltage profile and outstanding long hours plating/stripping compared to the bare Li. Compared to a bare Li anode, the graphite‐SiO2 bilayer modified Li anode coupled with lithium nickel cobalt manganese oxide cathode (NMC111) and lithium titanate shows improved capacity retention, higher capacity at higher rates, longer cycling stability, and lower voltage hysteresis. Graphite acts as an electrical bridge between the plated Li and Li electrode, which lowers the impedance and buffers the volume expansion during Li plating/stripping. Adding an ultrathin SiO2 layer facilitates Li‐ion diffusion and lithiation/delithiation, provides higher electrolyte affinity, higher chemical stability, and higher Young's modulus to suppress the Li dendrite growth.  相似文献   
152.
Multidrug resistance (MDR) is still a major threat to successful clinical application of cancer chemotherapy. Copper plays an important role in biological systems, and copper is also involved in carcinogenesis. In the present investigation, we addressed the question whether metal copper might be involved in drug resistance of murine and human tumors. By means of atomic absorption spectroscopy, we determined serum copper concentrations. We found that the blood serum of tumor-bearing mice contained higher amounts of copper than healthy mice with tumors. Secondly, mice bearing doxorubicin-resistant Ehrlich ascites carcinoma- or cyclophosphamide-resistant Lewis lung carcinoma contained more copper in their serum than mice bearing the corresponding drug-sensitive parental tumors. Furthermore, the analysis of patients with breast cancer, colon carcinoma or lung cancer showed that the serum copper contents were higher in patients not responding to chemotherapy when compared to patients whose tumors responded to treatment. The copper levels in serum of healthy volunteers were lower than in cancer patients irrespective of their response to chemotherapy. Our results imply that the level of serum copper may be considered as a biomarker for treatment response.  相似文献   
153.
In the present paper we show that extracts from Aegle marmelos Correa are able to inhibit the in vitro proliferation of human tumor cell lines, including the leukemic K562, T-lymphoid Jurkat, B-lymphoid Raji, erythroleukemic HEL, melanoma Colo38, and breast cancer MCF7 and MDA-MB-231 cell lines. Molecules present within the studied Aegle marmelos C. extracts were identified by gas-chromatography/mass-spectrometry analysis; three derivatives (butyl p-tolyl sulfide, 6-methyl-4-chromanone and butylated hydroxyanisole) were found to exhibit strong activity in inhibiting in vitro cell growth of human K562 cells. The antiproliferative activity of these compounds was found to be comparable to that of known antitumor agents, including cisplatin, chromomycin, cytosine arabinoside and 5-fluorouracil. In addition, the antiproliferative activity of butyl-p-tolyl sulfide, 6-methyl-4-chromanone and 5-methoxypsolaren was associated to activation of the differentiation pattern of K562 cells.  相似文献   
154.
Kaposi's sarcoma-associated herpesvirus (KSHV) is a human tumor virus expressing latent antigens critical for pathogenesis. The mechanism by which KSHV mediates oncogenesis has not been fully elucidated. Notch signaling is an evolutionarily conserved pathway controlling diverse events related to development, proliferation, and tissue homeostasis. Deregulation of Notch signaling has also been shown to be highly correlated with oncogenesis. Here we show that the activated intracellular domain of Notch1 (ICN) is aberrantly accumulated in latently KSHV-infected pleural effusion lymphoma cells and results in increased proliferation. Specifically, growth of the infected cells was dramatically inhibited at the G(1) phase by treatment with a gamma-secretase inhibitor which specifically blocks the production of ICN. Increased ICN also up-regulated the cyclin D1 cell cycle regulator. Taken together, these studies define an important mechanism directly linking latent KSHV infection to induction of oncogenesis through dysregulation of the conserved Notch signaling pathway.  相似文献   
155.
MDR- and CYP3A4-mediated drug-herbal interactions   总被引:8,自引:0,他引:8  
Pal D  Mitra AK 《Life sciences》2006,78(18):2131-2145
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156.
The changes in the metabolic status of both testis and ovary of Chrysocoris stolli following the treatment with juvenile hormone analogue (JHa) and ecdysterone were studied. After the exogenous application of JHa in selective dose, total carbohydrate, glycogen, trehalose, cholesterol, ascorbic acid and inorganic phosphorus increased significantly whereas free fatty acid (FFA), phospholipid, total protein, RNA and DNA decreased significantly in comparison to control of both testis and ovary. Total lipid significantly decreased in testis and significantly increased in ovary after JHa injection. The activities of cellular enzymes like alkaline phosphatase, 5' nucleotidase, catalase and peroxidase significantly decreased while acid phosphatase and GPT significantly increased after the JHa application in comparison to control both in testis and ovary. Activities of GOT and general esterase significantly decreased in testis and increased in ovary after JHa application. The exogenous application of ecdysterone also brought about the similar kind of responses as was noticed in case of JHa treatment but these two treatments differed in some cases such as ecdysteroid that produced some results which were just the reverse of what was produced by JHa treatment. The results obtained here were explained in terms of mode of action of these two hormones.  相似文献   
157.
Kar RK  Choudhuri MA 《Plant physiology》1986,80(4):1030-1033
Light treatment markedly accelerated chlorophyll loss in Hydrilla (Hydrilla verticillata [L.f.] Royle) over dark treatment whereas such acceleration could not be observed in spinach (Spinacia oleracea L.) leaf segments. Spermine, a polyamine, retarded the loss of chlorophyll in the dark but markedly accelerated this loss in the light during senescence of Hydrilla leaves. However, such effect of spermine in the dark was not so pronounced in spinach. The loss of protein was slower in the light than in the dark in both the species. Spermine arrested the loss of protein (as in spinach) or even raised the protein level over initial (as in Hydrilla). Loss of both soluble and insoluble protein was slower in light than in darkness. Spermine treatment, either in light or darkness, markedly accelerated the loss of soluble protein but raised the level of insoluble protein over initial in both the species. The pattern of change in α-amino nitrogen in either species could be correlated well with that of protein level. In Hydrilla, light increased the soluble protein fraction over initial and this rise was prevented by cycloheximide and not by chloramphenicol. Also, spermine augmented the protease activity (both acid and neutral) while light retarded the rise in protease activity during senescence of either species. Although spermine treatment reduced the leaching of α-amino nitrogen and electrolytes in Hydrilla, it augmented the same in spinach.  相似文献   
158.
Summary Two sublines from each of four flocks of White Leghorn were subjected to two cycles of selection for part year egg number and part year egg mass. A family index (combined selection) was the selection criterion for each of the two traits. The generation means of an unselected pedigreed randombred control, bred and maintained along with the selected sub-lines, were used for correcting short term environmental trends. The sublines selected for a common selection criterion were considered as replicates. The control corrected generation means, when averaged over replicates, gave the mean direct and correlated responses for the selected and different unselected traits. The average genetic change per generation was 2.16 eggs in egg number selected sublines and 146 g of egg mass in egg mass selected sublines. The direct response marginally exceeded the correlated response for both part period egg number and egg mass seen in the corresponding sublines. Except for egg weight the correlated responses for different unselected traits were in the same direction in both egg number and egg mass selected sublines. While the egg weight in egg number lines did not change, its response was positive in egg mass selected lines. A comparison between the lines revealed that the egg mass selected lines matured later and laid heavier but slightly less numerous eggs than the egg number selected sub-lines.  相似文献   
159.
Vigna cutjang Endl. cv. Pusa Barsati seedlings, subjected to increasing degrees of water stress (−0.5, −1.0, −1,5 MPa), produced an approximately proportional increase in glycolate oxidase activity, hydrogen peroxide (H2O2) and proline content but a decrease in catalase activity, ascorbic acid and protein content. Leaf water potential (leaf ψ) and relative water content (RWC) were also lowered with increasing stress. Pretreatment with l -cysteine and reduced glutathione (10-3 M) decreased glycolate oxidase activity, H2O2 content, ascorbic acid oxidase activity, proline content and also slightly improved the water status of leaves stressed (−1.0 MPa) for 2 days. Pretreatment of non-stressed seedlings with these antioxidants had little or no effect. These studies indicate that treatment with antioxidants makes the plant tolerant against water stress by modulating the endogenous levels of H2O2 and ascorbic acid in stressed tissue.  相似文献   
160.
Decreasing substrate osmotic potential produced in seedlings ofVigna catjang Endl. (cv. Pusa Barsati) proportional decrease in relative water content and leaf water potential, increase in respiration rate, proline content, H2O2 content, and the activities of indole acetic acid oxidase, ascorbic acid oxidase, peroxidase and glycolate oxidase but decrease in catalase activity and glycolate content. Pretreatment with reducing agents like L-cysteine or reduced glutathione (10?3 M) caused lower decrease in the relative water content, leaf water potential and glycolate content and reduced the rise of respiration rate, proline content and H2O2 content and also the activities of aforementioned oxidative enzymes, except catalase activity which was increased. Such treatments also maintained the chlorophyll and protein levels and decreased the tissue permeability. It was concluded that the treatment ofVigna seedlings with reducing agents reduced the deteriorative changes and oxidative processes which are characteristic of water stressed tissue.  相似文献   
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