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41.
Studies were undertaken to determine if a prewetting device (humidifier bulb) used in combination with an all glass impinger (AGI-30) would increase the recovery of airborne mengovirus-37A, vesicular stomatitis virus (VSV), and the S-13 coliphage. Suspensions of T3 coliphage with mengovirus-37A, VSV, or S-13 were aerosolized and collected by using the AGI-30-humidifier bulb combination to sample the aerosols before and after shifts in relative humidities (RH). These studies revealed the following. (i) At low RH values there was a 3 to 4 log increase in recovery of airborne T3 phage; (ii) concomitantly, the recovery of mengovirus-37A and VSV decreased; and (iii) only at the mid-range RH values was the recovery of S-13 enhanced. The prehumidification technique significantly increased the recovery of airborne T3 phage but decreased the recovery of the two animal viruses tested.  相似文献   
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The interpretation of the heavy metal-labeled data can either be accomplished with the analysis of the observed intensity differences (Akers and Parsons) or with the analysis of the observed structure amplitude changes (Harker). Both methods of analysis give essentially the same results: that two possible electron density distributions are valid, within experimental error, depending on whether there are one or two metal-labeling sites within the membrane. At present, the correct choice must rest on either the introduction of additional physical and chemical data on the position of the proteins and lipids or on an independent phasing technique such as the Hosemann-Bagchi Q-function.  相似文献   
43.
Airborne Stability of Simian Virus 40   总被引:1,自引:0,他引:1       下载免费PDF全文
The influence of relative humidity on the airborne survival of simian virus 40 (SV40) was studied by allowing virus aerosols to age in rotating drums at 21 or 32 C and at a relative humidity (RH) value ranging from 22 to 88%. Airborne SV40 virus was stable at every RH tested at 21 C, but aerosols maintained at 32 C were inactivated within 60 min at mid-range RH values. The unusual stability at 21 C over a broad RH range indicates that potentially biohazardous situations may occur under laboratory conditions if this virus becomes accidentally airborne.  相似文献   
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Amine N-oxides have been observed to be reduced by titanium(III) chloride. To study this reaction, 24 model amine N-oxides were reacted with titanium(III) chloride. The products of these reactions were shown by melting (boiling) points, mixed melting points, derivatives, refractive indices, infrared, and NMR comparisons with authentic compounds to be the corresponding amines. The reductions were found to require 2 moles of titanium(III) per mole of amine N-oxide.  相似文献   
46.
An interaction between sarcoma-180/TG cells and vesicular stomatitis virus in adult mice resulted in the rapid onset of extensive mortality. This interaction, termed lethal synergy, occurred only at early stages of ascites induction in animals with no prior virus contact. A significant sparing effect conferred by the serotonin antagonist dibenamine was reversed by the administration of serotonin. The cause of death was not determined, but a mechanism involving hypersensitivity is indicated.  相似文献   
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Epithelial ovarian cancer (EOC) is a highly lethal malignancy due to a lack of early detection approaches coupled with poor outcomes for patients with clinically advanced disease. Cancer-testis (CT) or cancer-germline genes encode antigens known to generate spontaneous anti-tumor immunity in cancer patients. CT45 genes are a recently discovered 6-member family of X-linked CT genes with oncogenic function. Here, we determined CT45 expression in EOC and fully defined its epigenetic regulation by DNA methylation. CT45 was silent and hypermethylated in normal control tissues, but a large subset of EOC samples showed increased CT45 expression in conjunction with promoter DNA hypomethylation. In contrast, copy number status did not correlate with CT45 expression in the TCGA database for EOC. CT45 promoter methylation inversely correlated with both CT45 mRNA and protein expression, the latter determined using IHC staining of an EOC TMA. CT45 expression was increased and CT45 promoter methylation was decreased in late-stage and high-grade EOC, and both measures were associated with poor survival. CT45 hypomethylation was directly associated with LINE-1 hypomethylation, and CT45 was frequently co-expressed with other CT antigen genes in EOC. Decitabine treatment induced CT45 mRNA and protein expression in EOC cells, and promoter transgene analyses indicated that DNA methylation directly represses CT45 promoter activity. These data verify CT45 expression and promoter hypomethylation as possible prognostic biomarkers, and suggest CT45 as an immunological or therapeutic target in EOC. Treatment with decitabine or other epigenetic modulators could provide a means for more effective immunological targeting of CT45.  相似文献   
50.
Antiestrogen is one type of the endocrine therapeutic agents for estrogen receptor α (ERα)-positive breast cancer. Unfortunately, this treatment alone is insufficient. Here we reported a novel potential anticancer strategy by using histone deacetylase (HDAC) inhibitor to enhance the action of endocrine therapy in ERα-positive breast cancer cell. The well-described HDAC inhibitor, trichostatin A (TSA), and antiestrogen raloxifene were found to, respectively, inhibit E2-induced proliferation of MCF-7 breast cancer cell in a dose-responsive and time-dependent manner. TSA and raloxifene enhanced the antiproliferative activity of each other by promoting cell death via apoptosis and cell cycle arrest. Thus, they displayed better antiproliferative effects in combined treatment than that with either agent alone. The expression level of estrogen receptor β (ERβ) showed a marked increase after TSA or/and raloxifene treatment. Treatments with TSA or/and raloxifene resulting in the up-regulation of ERβ are in accordance with the antiproliferative effects of the two agents. Furthermore, the over-expression of ERβ by adenovirus delivery could inhibit the proliferation of MCF-7 tumor cells and drastically enhanced the antiproliferative effects of TSA and raloxifene. These results demonstrated that the interference of ERβ on the antiproliferative effects of HDAC inhibitor and antiestrogen constitutes a promising approach for breast cancer treatment.  相似文献   
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