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91.
92.
FCE 24304 (6-methylenandrosta-1,4-diene-3,17-dione), a new irreversible aromatase inhibitor, has been identified and characterized in vitro and in vivo. The compound caused time-dependent inactivation of human placental aromatase with a t1/2 of 13.9 min and ki of 26 nM. When tested in PMSG-treated rats, ovarian aromatase activity was reduced 24 h after dosing by both the s.c. (ED50 1.8 mg/kg) and the oral (ED50 3.7 mg/kg) routes. No interference with 5 alpha-reductase activity nor any significant binding affinity for estrogen receptor was found. Slight binding affinity for the androgen receptor (RBA 0.2% of DHT) was observed.  相似文献   
93.
Vinegar production is based on the acetification process by indigenous acetic acid bacteria (AAB). Among vinegar technologies, solid-state fermentation (SSF) processes are widespread in Asian countries to produce vinegar at small-scale. In this study, 21 AAB strains isolated from Chinese cereal vinegars produced by SSF collected in different regions of China were characterized by enterobacterial repetitive intergenic consensus (ERIC)–PCR fingerprinting. Isolates exhibited high degree of phenotypic variability as well as suitable traits for their uses as selected strains in SSF vinegar production (growth modality by superficial biofilm, no production of cellulose, ability to growth on ethanol media). 16S rRNA gene sequencing analysis of representative strains showed that strains of Acetobacter pasteurianus have a close association to cereal vinegars, whereas Gluconacetobacter europaeus population is not favoured. Selection of single or multiple strains culture within A. pasteurianus species was predicted in view of their application in SSF technology. This seems to be the first report showing phenotypic and genetic variability of AAB strains involved in SSF processes. Results can be exploited for the implementation of large-scale SSF processes by selected strains for vinegar production and other innovative biotechnological applications.  相似文献   
94.
We report for the first time the presence of Galba neotropica in Santa Fe province, Pampean Argentina. Until the present work, the identity of the intermediate host of Fasciola hepatica in this region, the most important livestock production area of Argentina, was unknown. This report extends the geographic distribution of G. neotropica and is the first to provide molecular and morphological information on this species in Argentina. During summer 2013, snails were collected on private livestock farms with high prevalence of fasciolosis in cattle. Specimens were identified by using the nuclear sequences of the internal transcribed spacers ITS-1 and ITS-2, the shell and the shape and size of the male reproductive organs. Molecularly, ITS-1 and ITS-2 nuclear sequences exhibit 100% nucleotide identity with G. neotropica from Lima, Peru. Morphologically, G. neotropica from Santa Fe province was indistinguishable from Galba viatrix and Galba cubensis, the other two cryptic species within this South American group of lymnaeids. The combination of molecular and morphological analyses is strongly recommended to identify lymnaeids at species level. The identity of the intermediate host and the subsequent knowledge of its susceptibility, behaviour, distribution, ecology and biology are important components in developing effective measures to control fasciolosis.  相似文献   
95.

Background

Crohn’s disease (CD) and Hidradenitis suppurativa (HS) are both chronic inflammatory diseases. The pathogenesis of these diseases is multifactorial, due to the interaction of genetic and environmental factors leading to a deregulated local immune response where T lymphocytes play a major role. To the best of our knowledge, no previous study has clarified whether the pathogenetic mechanism of perianal CD and HS is the same. We therefore analyzed the cellular expression pattern and the cytokine repertoire in three patients suffering from both perianal CD and HS.

Methods

We evaluated three patients affected by concurrent HS and CD with fistulizing perianal disease. Surgical specimens have been fixed and embedded in paraffin prior to sectioning for histological examination. Inflammatory tissue curettages have been recovered during intervention from perianal fistulas and HS lesions in order to analyze the phenotypic and functional characteristics of infiltrating T cells. In particular we evaluated T cells, by flow cytometry, for cytokine production profile and expression of surface markers. Moreover, analysis of the T cell repertoire was performed by means of spectratyping, in only one patient.

Results

A higher frequency of CD4+ CD161+ T lymphocytes has been detected in CD fistulas and in HS lesions than in peripheral blood (PB) samples. In the patient in whom we derived enough cells from the three sources, we found higher frequency of CD4+ IL-17- producing cells in HS lesion and fistula lesion compared to PB. It is noteworthy that the same clonotypes were expanded in this patient in T cells derived from both HS lesion and fistula lesion.

Conclusion

The presence of numerous CD4+ CD161+ lymphocytes in fistula and HS lesion curettages suggests that these cells may play a pathogenic role, and candidates CD161 as a possible biological target for medical treatment.  相似文献   
96.
It has been shown that anti-cancer drug induces secretion of serotonin (5-HT) from small intestine which activates serotonin type 3 (5-HT3) receptor to cause nausea and vomiting. In general, antagonist for 5-HT3 receptor is used as anti-emetics during chemotherapy. However, we found that anti-cancer drug irinotecan itself inhibits 5-HT-gated current through the homomeric 5-HT3A and heteromeric 5-HT3AB receptor in a concentration-dependent manner. The inhibitory effect of irinotecan on 5-HT3A receptor was more potent than that on 5-HT3AB receptor. On the other hand, SN-38, a metabolite of irinotecan, had no effect on the responsiveness. Our findings suggest that irinotecan itself could have anti-emetic activities through inhibition of the 5-HT3A and 5-HT3AB receptor.  相似文献   
97.
Control over malolactic fermentation (MLF) is a difficult goal in winemaking and needs rapid methods to monitor Oenococcus oeni malolactic starters (MLS) in a stressful environment such as wine. In this study, we describe a novel quantitative PCR (QPCR) assay enabling the detection of an O. oeni strain during MLF without culturing. O. oeni strain LB221 was used as a model to develop a strain-specific sequence-characterized amplified region (SCAR) marker derived from a discriminatory OPA20-based randomly amplified polymorphic DNA (RAPD) band. The 5' and 3' flanking regions and the copy number of the SCAR marker were characterized using inverse PCR and Southern blotting, respectively. Primer pairs targeting the SCAR sequence enabled strain-specific detection without cross amplification of other O. oeni strains or wine species of lactic acid bacteria (LAB), acetic acid bacteria (AAB), and yeasts. The SCAR-QPCR assay was linear over a range of cell concentrations (7 log units) and detected as few as 2.2 × 10(2) CFU per ml of red wine with good quantification effectiveness, as shown by the correlation of QPCR and plate counting results. Therefore, the cultivation-independent monitoring of a single O. oeni strain in wine based on a SCAR marker represents a rapid and effective strain-specific approach. This strategy can be adopted to develop easy and rapid detection techniques for monitoring the implantation of inoculated O. oeni MLS on the indigenous LAB population, reducing the risk of unsuccessful MLF.  相似文献   
98.
The effects of Copper on the life-cycle of two crustacean isopods, Asellus aquaticus (L.) and Proasellus coxalis Dollf., are studied. ST50 indicates that females and males are differently sensitive in comparison with juveniles. The two species do not show differences in sensitivity in the range of 0.01–15 mg·1-1 between adults and juveniles. The effect of 0.005 mg·1-1 Copper sulphate was strongest on embryonic and larval stages. Ecological implications are discussed.  相似文献   
99.
Light control of amaranthin synthesis in isolated Amaranthus cotyledons   总被引:1,自引:0,他引:1  
The effect of light on the amaranthin synthesis stimulated by exogenous precursors has been studied in isolated cotyledons of Amaranthus tricolor and A. caudatus. The results indicate that light acts at the level of the formation of the dihydropyridine moiety of the pigment.  相似文献   
100.
Bonellin, a chlorin extracted fromBonellia viridis (Echiura), and hemaatoporphyrin exhibit a strong antibiotic and bactericidal activity on marine and terrestrial bacteria. This action is enhanced by light. Oxygen consumption and motility of bacteria are also inhibited, while no chemotactic effects are observed. The drugs induce lysis onBacillus subtilis protoplasts, but they are ineffective onMicrococcus lysodeikticus protoplasts.The results are discussed and compared with those obtained with eukariotic cells. Attention is focused on the ecological role of bonellin in the defense mechanism ofBonellia viridis.  相似文献   
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