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11.
The effects of single doses (3 g/kg and 9 g/kg) of 35% ethanol, on the glutathione (GSH) contents of the blood, liver and kidneys of Rana temporaria L. were studied in the annual cycle. It was found that the single doses of ethanol generally caused a significant increase of GSH in the blood and liver of males and females of Rana temporaria L. in each period of the annual cycle as compared with the control values. In time, it was found that the same doses of ethanol caused a significant decrease in the GSH content of the kidneys of the male and female Rana temporaria L. during their active land life and a strong increase of this tripeptide during hibernation.  相似文献   
12.

Uxmal and Tulum are two important Mayan sites in the Yucatan peninsula. The buildings are mainly composed of limestone and grey/black discoloration is seen on exposed walls and copious greenish biofilms on inner walls. The principal microorganisms detected on interior walls at both Uxmal and Tulum were cyanobacteria; heterotrophic bacteria and filamentous fungi were also present. A dark‐pigmented mitosporic fungus and Bacillus cereus, both isolated from Uxmal, were shown to be acidogenic in laboratory cultures. Cyanobacteria belonging to rock‐degrading genera Synechocystis and Gloeocapsa were identified at both sites. Surface analysis previously showed that calcium ions were present in the biofilms on buildings at Uxmal and Tulum, suggesting the deposition of biosolubilized stone. Apart from their potential to degrade the substrate, the coccoid cyanobacteria supply organic nutrients for bacteria and fungi, which can produce organic acids, further increasing stone degradation.  相似文献   
13.
Novel series of N-benzyl 1,4-dihydropyridines have been prepared by facile syntheses. All relevant substituents of the molecular scaffold have been varied. The resulting compounds were biologically evaluated as P-glycoprotein (P-gp) inhibitors. Substitutions of the N-benzyl residue favour biological activity beside respective 3-ester functions. Most active compounds were further evaluated as multidrug resistance (MDR) modulators to restore the cytotoxic properties of varying daunorubicin applications.  相似文献   
14.
Abstract

Sexually mature male and female Rana esculenta L. were captured in their natural habitat in six phases of the annual cycle. Nuclear volumes in APOA cells were found to fluctuate distinctly in the course of the year. In both sexes nuclear volumes were maximal in the phases preceding the breeding season (IIIrd decade of January, and 1st decade of April), and minimal throughout the phases of active life (IIIrd decade of May, IInd decade of July, and 1st decade of September). No aldehydefuchsin or Gomori‐positive material was found in the APOA perikaryons.  相似文献   
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16.
We have compared the effect of one and up to four local IL-2 treatments of transplanted MC38 colon carcinoma. A single IL-2 treatment prolonged the survival time (p=0.015), but no cure was obtained. One local IL-2 treatment inhibited tumor growth for about 1 week. After the start of tumor regrowth, a further IL-2 injection was given. After four IL-2 injections 6 out of 13 mice were cured. Histological studies show that IL-2 induced a local vascular leakage syndrome leading to massive peritumoral edema and subsequent necrosis of tumor tissue. IL-2 also attracted infiltrating cells, mainly macrophages. Subsequent IL-2 injections led to complete tumor regression. We believe that the combination of necrotic tumor debris and the IL-2–induced macrophage reaction enhanced a tumor-specific immune response. This local IL-2 application was not toxic.  相似文献   
17.
Amplification of DNA fragments surrounding rare restriction sites (ADSRRS-fingerprinting) is a novel assay based on suppression of polymerase chain reaction (PCR). This phenomenon allows the amplification of only a limited subset of DNA fragments, since only those with two different oligonucleotides ligated at the ends of complementary DNA strands are amplified in the PCR. The DNA fragments can be easily analyzed on polyacrylamide gels, stained with ethidium bromide. We have implemented this method using a set of clinical Serratia marcescens isolates from three outbreaks ongoing in the Public Hospital in Gdańsk (Poland). Clustering of ADSRRS-fingerprinting data matched epidemiological, microbiological, random amplification of polymorphic DNA (RAPD) and pulsed-field gel electrophoresis (PFGE) data. Based on this study, we found that there is at least a similar power of discrimination between the present 'gold-standard' PFGE and the novel method, ADSRRS-fingerprinting. Although the ADSRRS-fingerprinting method may appear to be more complex than the RAPD technique, we found it fast and reproducible.  相似文献   
18.
The biosensor with urease entrapped in PVC layer at the surface of pH-sensitive iridium oxide electrode was applied for testing of mercury and other metal ions inhibition on enzymatic reaction. The calculation of inhibition effect was based on the measurement of initial rate of decrease of biosensor potential (proportional to the initial rate of enzymatic reaction) after addition of substrate after inhibition step. Some differences of inhibition extent were observed for various mercury forms (Hg(NO3)2, HgCl2, PhHgCl and Hg2(NO3)2) as well as for other heavy metal ions investigated as potential interferents. Because the method was not specific, it was applied for the determination of total inhibition effect caused by heavy metal ions in water samples. In the case of most cations tested the total recovery of enzyme activity was possible using Tris buffer solution with EDTA and thioacetamide after less than 10 min regeneration time.  相似文献   
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20.
The increasing incidence of acyclovir (ACV) and multidrug-resistant strains in patients with corneal HSV-1 infections leading to Herpetic Stromal Keratitis (HSK) is a major health problem in industrialized countries and often results in blindness. To overcome this obstacle, we have previously developed an HSV-gB-specific monoclonal antibody (mAb 2c) that proved to be highly protective in immunodeficient NOD/SCID-mice towards genital infections. In the present study, we examined the effectivity of mAb 2c in preventing the immunopathological disease HSK in the HSK BALB/c mouse model. Therefore, mice were inoculated with HSV-1 strain KOS on the scarified cornea to induce HSK and subsequently either systemically or topically treated with mAb 2c. Systemic treatment was performed by intravenous administration of mAb 2c 24 h prior to infection (pre-exposure prophylaxis) or 24, 40, and 56 hours after infection (post-exposure immunotherapy). Topical treatment was performed by periodical inoculations (5 times per day) of antibody-containing eye drops as control, starting at 24 h post infection. Systemic antibody treatment markedly reduced viral loads at the site of infection and completely protected mice from developing HSK. The administration of the antiviral antibody prior or post infection was equally effective. Topical treatment had no improving effect on the severity of HSK. In conclusion, our data demonstrate that mAb 2c proved to be an excellent drug for the treatment of corneal HSV-infections and for prevention of HSK and blindness. Moreover, the humanized counterpart (mAb hu2c) was equally effective in protecting mice from HSV-induced HSK when compared to the parental mouse antibody. These results warrant the future development of this antibody as a novel approach for the treatment of corneal HSV-infections in humans.  相似文献   
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