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81.
Molara is a small island belonging to the Marine protected Area Tavolara—Punta Coda Cavallo, in Sardinia. During 2006–2007, a bio-monitoring program reported a strong presence of the black rat, Rattus rattus, on Molara island. Rat predation has detrimentally affected the unique biodiversity of this island, thus, in 2008 an eradication campaign was conducted. Our eradication protocol included a pre-eradication genetic investigation, using 8 microsatellite loci, on a rat population of Molara as well as on neighbour islands within the Marine Protected Area (MPA). The main goal of this genetic investigation was to establish the correct borders of the eradication unit of Molara island. As several recent eradication campaigns have been unsuccessful, due to incomplete and unstable eradication, we also aimed to assess possible hidden sources of reinvasion. Specimens were also collected during post- eradication monitoring on Molara for genetic screening to establish their origin, and thus validate the effectiveness of our eradication campaign. According to our genetic analysis, within the MPA there are four different eradication units, corresponding to the islands of Molara, Tavolara, Piana and to the Sardinia mainland. Gene flow among these four units is more or less absent. The assignment and clustering tests performed on pre and post-eradication samples seem to indicate that the population of Sardinia mainland is a possible source of re-invasion for the Piana and Molara populations.  相似文献   
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Wheat contains various essential nutrients including the B group of vitamins. However, B group vitamins, normally present in cereals-derived products, are easily removed or destroyed during milling, food processing or cooking. Lactic acid bacteria (LAB) are widely used as starter cultures for the fermentation of a large variety of foods and can improve the safety, shelf life, nutritional value, flavor and overall quality of the fermented products. In this regard, the identification and application of strains delivering health-promoting compounds is a fascinating field. Besides their key role in food fermentations, several LAB found in the gastrointestinal tract of humans and animals are commercially used as probiotics and possess generally recognized as safe status. LAB are usually auxotrophic for several vitamins although certain strains of LAB have the capability to synthesize water-soluble vitamins such as those included in the B group. In recent years, a number of biotechnological processes have been explored to perform a more economical and sustainable vitamin production than that obtained via chemical synthesis. This review article will briefly report the current knowledge on lactic acid bacteria synthesis of vitamins B2, B11 and B12 and the potential strategies to increase B-group vitamin content in cereals-based products, where vitamins-producing LAB have been leading to the elaboration of novel fermented functional foods. In addition, the use of genetic strategies to increase vitamin production or to create novel vitamin-producing strains will be also discussed.  相似文献   
84.
The aim of the present study was to establish a new procedure for the oenological selection of Saccharomyces cerevisiae strains isolated from natural must fermentations of an important Italian grape cultivar, denoted as “Negroamaro”. For this purpose, 108 S. cerevisiae strains were selected as they did not produce H2S and then assayed by microfermentation tests. The adopted procedure made it possible to identify 10 strains that were low producers of acetic acid and hydrogen sulphide and showed that they completed sugar consumption during fermentation. These strains were characterized for their specific oenological and technological properties and, two of them, strains 6993 and 6920, are good candidates as industrial starter cultures. A novel protocol was set up for their biomass production and they were employed for industrial-scale fermentation in two industrial cellars. The two strains successfully dominated the fermentation process and contributed to increasing the wines’ organoleptic quality. The proposed procedure could be very effective for selecting “company-specific” yeast strains, ideal for the production of typical regional wines. “Winery” starter cultures could be produced on request in a small plant just before or during the vintage season and distributed as a fresh liquid concentrate culture.  相似文献   
85.
We investigated changes in cadherin structure at the cell surface that regulate its adhesive activity. Colo 205 cells are nonadhesive cells with a full but inactive complement of E-cadherin-catenin complexes at the cell surface, but they can be triggered to adhere and form monolayers. We were able to distinguish the inactive and active states of E-cadherin at the cell surface by using a special set of monoclonal antibodies (mAbs). Another set of mAbs binds E-cadherin and strongly activates adhesion. In other epithelial cell types these activating mAbs inhibit growth factor-induced down-regulation of adhesion and epithelial morphogenesis, indicating that these phenomena are also controlled by E-cadherin activity at the cell surface. Both types of mAbs recognize conformational epitopes at different interfaces between extracellular cadherin repeat domains (ECs), especially near calcium-binding sites. Activation also induces p120-catenin dephosphorylation, as well as changes in the cadherin cytoplasmic domain. Moreover, phospho-site mutations indicate that dephosphorylation of specific Ser/Thr residues in the N-terminal domain of p120-catenin mediate adhesion activation. Thus physiological regulation of the adhesive state of E-cadherin involves physical and/or conformational changes in the EC interface regions of the ectodomain at the cell surface that are mediated by catenin-associated changes across the membrane.  相似文献   
86.
Several experimental and clinical observations indicate that ethanol ingestion induces specific neurochemical modifications in the Central Nervous System. In particular, an involvement of endogenous opiates has been suggested in the case of alcohol addiction. In this light, the plasma concentrations of met-enkephalin immunoreactive peptides (ME-IR) have been measured in selected groups of chronic alcoholics and in children whose mothers were ethanol addicts. Both groups revealed a marked reduction of ME-IR plasma concentrations when compared with sex and age matched controls.  相似文献   
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88.
The effects induced by different concentrations (50, 75, 100 microM) of the cytostatic drug cisplatin (cDDP) in NIH/3T3 cells were analyzed. Sub-confluent cultures of this mouse fibroblast line, obtained after serum deprivation, showed the presence of aneuploid/polyploid cells with ploidy values ranging from 4c to 24c. DNA content cytofluorometry demonstrated that 50 and 75 microM cDDP induced a cytostatic effect; 100 microM concentration showed lower antiproliferative action. All treatments caused a partial cell detachment and apoptosis, the incidence of which appeared to be cDDP concentration-dependent. Ultrastructural and fluorescence microscopy integrated analyses of the still adherent cells demonstrated the presence of alternative degeneration patterns, especially in polyploid cells, with extensive modifications at both nuclear and cytoplasmic levels. There were events of micronucleation and phenomena of multilobulation and furrows of the nucleus that preceded the formation of heterogeneous fragments. These events were correlated, at cytoplasmic level, with actin reorganization and the appearance of autophagocytotic processes. In our cell model, the same pharmacological treatment was able to induce different cell death phenomena relating to cell dimension and ploidy. More actively proliferating cells (2c-4c DNA content) die throughout canonical apoptosis, while polyploid cells prevailingly degenerate by mechanisms partly referable to autophagic cell death.  相似文献   
89.
The relationship between apoptotic progression and cell cycle perturbation induced by microtubule-destabilising (vinblastine, Colcemid) and -stabilising (taxol) drugs was studied in two mesenchyme-derived neoplastic cell lines, growing as suspension (Jurkat) and monolayer (SGS/3A) culture, by morphocytochemical and biochemical approaches. The same kind of drug induced different effects on the cell kinetics (proliferation, polyploidisation, death) of the two cell lines. In floating cells, the drugs appeared more effective during the S phase, while in adherent cells they were more effective during the G2/M phase. Moreover two distinct neoplasia-associated apoptotic phenotypes emerged: the first pattern was the typical one and was found in cells with a low transition through the S/G2 phase (Jurkat), and the second one was mainly characterised by a cell death derived from micronucleated and mitotic cells, as a consequence of a low transition through the M/G1 phase (SGS/3A). Our data show that the machinery required for the trigger and progression of apoptosis is present in every cell cycle phase, also in conditions of karyological alterations (aneugenic micronucleations). On the other hand, a different sensitivity of the two microtubular components (interphasic network and mitotic spindle) appears to be related to the anchorage-dependence or -independence during the cell growth disturbances after exposure to antimicrotubular drugs.  相似文献   
90.
AIMS: Physiological and molecular analysis such as PCR species-specific and randomly amplified polymorphic PCR (RAPD-PCR) have been used for typing of Lactobacillus plantarum strains from typical wine must. METHODS AND RESULTS: Phenotypic tests such as API 50CH and evaluation of D-L-lactate production from glucose were used to perform a preliminary characterization of lactobacilli. Furthermore, 18 strains of lactobacilli were analyzed by PCR species-specific oligonucleotides based on short sequences of the recA gene. CONCLUSIONS: Four strains were identified as belonging to the L. plantarum species and were further analysed by RAPD-PCR. The RAPD-PCR profiles were similar in all strains that had positive results for species-specific PCR, suggesting that the four L. plantarum strains were closely related. SIGNIFICANCE AND IMPACT OF THE STUDY: Using PCR species-specific as a preliminary screening test and then RAPD-PCR can be as considered the most reliable method of performing a rapid and correct typing of L. plantarum from wine must.  相似文献   
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