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We have isolated, partially purified, and characterized the 5 alpha-petromyzonol (5 alpha-PZ), (5 alpha-cholan- 3 alpha, 7 alpha, 12 alpha, 24-tetrahydroxy-) sulfotransferase (PZ-SULT) from larval lamprey liver. Crude liver extracts exhibited a PZ-SULT activity of 0.9120 pmol/min/mg in juvenile and 12.62 pmol/min/mg in larvae. Using crude larval liver extracts and various 5 beta-cholan substrates and allocholic acid there was negligible activity, however, with 5 alpha-PZ and 3-keto-5 alpha-PZ the SULT activity was 231.5 pmol/min/mg and 180.8 pmol/min/mg respectively. This established that the sulfotransferase of lamprey larval liver extracts prefers (5 alpha) substrates and it is selective for hydroxyl at C-24. PZ-SULT was purified through various chromatography procedures. Partially purified PZ-SULT exhibited a pH optimum of 8.0, a temperature optimum of 22 degrees C, and activity was linear for 1h. PZ-SULT exhibited a K(m) of 2.5 microM for PAPS and a K(m) of 8 microM for PZ. The affinity purified peak PZ-SULT exhibited a specific activity of 2,038 pmol/min/mg. The peak protein upon SDS-PAGE, correlated to an Mw 47 kDa. Photoaffinity labeling with PAP(35)S, specifically crosslinked the 47 kDa protein, further confirming the identity of PZ-SULT. Partial amino acid sequencing of the putative 47 kDa PZ-SULT protein yielded a peptide sequence (M)SISQAVDAAFXEI, which possessed an overall (approximately 35-40%) homology with mammalian SULT2B1a.  相似文献   
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Human hepatitis E virus (HEV) is considered an emerging pathogen in industrialized countries. In Italy, the true burden of HEV infection is unknown. Molecular HEV screening of raw sewage samples from 11 wastewater treatment plants yielded 19 positives (16%; 18 genotype I, 1 genotype III) evenly distributed throughout Italy. Evidence that HEV could be establishing itself in our region is accumulating and may justify more active surveillance to monitor its spread.Hepatitis E is a self-limited, enterically transmitted acute viral hepatitis that occurs most frequently in epidemic outbreaks and often spreads by way of fecally contaminated drinking water (5, 20). Hepatitis E virus (HEV) infections are caused by a positive-sense, nonenveloped RNA virus of the Hepevirus genus. The four major genotypes (GI to GIV), all belonging to a single serotype, are known to infect humans. While GI and GII are restricted to humans, GIII and GIV are zoonotic and may infect animals (swine, chickens, deer, mongooses, and rabbits), as well as humans, in both industrialized and nonindustrialized countries (18, 19). GI consists of epidemic strains circulating in Africa and Asia. GII is found in Mexico and Africa. GIII is widely distributed, mainly—but not exclusively—in the United States, Europe, and Japan. GIV is present in Asia (16). An HEV strain belonging to a fifth genotype has been identified in birds (12).HEV is transmitted by the fecal-oral route. Large waterborne outbreaks with high attack rates among young adults have been described in regions characterized by poor sanitary conditions (22). Hepatitis E is responsible for over 50% of cases of acute viral hepatitis in countries where the disease is endemic (Central and Southeast Asia, North and West Africa, and Mexico), where seroprevalence rates range from 15% to 60% (8). North America and Europe have traditionally been considered areas where HEV is not endemic, with acute infection diagnosed rarely and largely confined to travelers returning from areas where the disease is endemic. The high rates of HEV IgG positivity reported in different studies, however, suggest that unrecognized or subclinical infection is common (8). In Europe, increasing numbers of HEV infections not associated with travel have been recently reported (15).HEV infection may vary in severity from asymptomatic to fulminant. Case fatality rates range between 0.5% and 4% overall but may reach 25% among pregnant women (1). In industrialized countries, the case fatality rate seems to be higher than in areas where the disease is endemic, since infection occurs more frequently in elderly people with chronic liver disease, a subgroup of patients with a case fatality rate approaching 70% (26).HEV, which is shed in the feces of infected individuals, has been detected in sewage samples, suggesting that HEV contamination of aquatic environments may also be present (2, 6, 7, 23). In Italy, the true burden of HEV infection is still unknown and there are no available studies on the presence of this virus in sewage. The prevalence of anti-HEV antibodies among healthy individuals has been found to be approximately 1% in the northern regions and up to 5% in the southern regions, including Sicily and Sardinia. Higher prevalence rates have been found among drug users (especially HIV-infected individuals), hemodialysis patients, and patients with chronic hepatitis C, suggesting that HEV may be transmitted not only by the fecal-oral route (the main mode of transmission) but also parenterally (27).The objective of the present study was to investigate the occurrence of HEV through the molecular screening of raw sewage samples collected from urban wastewater treatment plants (WTPs) in different regions of Italy.  相似文献   
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Inhibitory immune checkpoint (ICP) molecules are important immunosuppressive factors in a tumor microenvironment (TME). They can robustly suppress T-cell-mediated antitumor immune responses leading to cancer progression. Among the checkpoint molecules, cytotoxic T-lymphocyte-associated protein-4 (CTLA-4) is one of the critical inhibitors of anticancer T-cell responses. Besides, the expression of adenosine receptor (A2AR) on tumor-infiltrating T cells potently reduces their function. We hypothesized that concomitant silencing of these molecules in T cells might lead to enhanced antitumor responses. To examine this assumption, we purified T cells from the tumor, spleen, and local lymph nodes of CT26 colon cancer-bearing mice and suppressed the expression of A2AR and CTLA-4 using the small interfering RNA (siRNA)-loaded polyethylene glycol-chitosan-alginate (PCA) nanoparticles. The appropriate physicochemical properties of the produced nanoparticles (NPs; size of 72 nm, polydispersive index [PDI] < 0.2, and zeta potential of 11 mV) resulted in their high efficiency in transfection and suppression of target gene expression. Following the silencing of checkpoint molecules, various T-cell functions, including proliferation, apoptosis, cytokine secretion, differentiation, and cytotoxicity were analyzed, ex vivo. The results showed that the generated nanoparticles had optimal physicochemical characteristics and significantly suppressed the expression of target molecules in T cells. Moreover, a concomitant blockade of A2AR and CTLA-4 in T cells could synergistically enhance antitumor responses through the downregulation of PKA, SHP2, and PP2Aα signaling pathways. Therefore, this combination therapy can be considered as a novel promising anticancer therapeutic strategy, which should be further investigated in subsequent studies.  相似文献   
46.
Manipulation of micro- and nanoparticles in complex biofluids is highly demanded in most biological and biomedical applications. A significant number of microfluidic platforms have been developed for inexpensive, rapid, accurate, and efficient particle manipulation. Due to the enormous potential of viscoelastic fluids (VEFs) for particle manipulation, various emerging microfluidic-based VEFs techniques have been presented over the last decade. This review provides an intuitive understanding of VEF physics for particle separation in different microchannel geometries. Besides, active and passive VEF methods are critically reviewed, highlighting the potential and practical challenges of each technique for particle/cell focusing, sorting, and separation. The outcome of this study could enable recognizing deliverable VEF technology with the promising prospect in the manipulation of submicron biological samples (e.g., exosomes, DNA, and proteins).  相似文献   
47.
Neuroblastoma (NB), a neuroendocrine tumour, is one of the most prevalent cancers in children. The link between LMO1 polymorphisms and NB has been investigated by several groups, rendering inconclusive results. Here, with this comprehensive systematic review and up‐to‐date meta‐analysis, we aim to distinctively elucidate the possible correlation between LMO1 polymorphisms and NB susceptibility. Eligible studies were systematically researched and identified using PubMed, Web of Science and Scopus databases up to 10 February 2019. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to assess the strength of the associations. Our findings revealed that rs110419 and rs2168101 polymorphisms were significantly associated with a decreased risk of NB in all genetic models. In addition, the rs4758051 variant appeared protective against NB in homozygous, dominant and allele genetic models, whereas the rs10840002 variant markedly decreased the risk of NB in the allele model. In contrast, the rs204938 polymorphism showed a positive association with NB susceptibility in allele genetic models. In summary, our meta‐analysis is the first to provide clear evidence of an association between specific polymorphisms of LMO1 and susceptibility to NB. Of note, additional larger well‐designed studies would be helpful to further evaluate and confirm this association.  相似文献   
48.
International Journal of Peptide Research and Therapeutics - Beneficial effects of MYC such as antioxidant, cytoprotective and antimicrobial activity have been investigated in various studies. The...  相似文献   
49.
To study genetically and evaluate resistance to yellow rust, 29 wheat advanced lines were evaluated in randomised complete blocks design with three replicates in seedling stage under greenhouse conditions using nine races 6E150A+, 198E150A+, 134E150A+, 6E158A+, 166E150A+, 198E130A+, 166E158A+, 230E158A+ and 70E0A+, separately. In the adult plant stage, the genotypes were evaluated in two regions of Iran, Zarghan and Gorgan. The components of resistance including latent period and infection type were recorded under greenhouse conditions. Cluster analysis in all races showed that the genotypes 11, 28 and 29 were completely resistant to all races. Under Zarghan and Gorgan races, 27 and 73% of genotypes were resistant in the adult plant stage, respectively. Seven percent of genotypes were resistant in both stages, seedling and adult plant. All resistant lines can be used in plant breeding programme.  相似文献   
50.
Liposomal cytarabine, DepoCyt, is a chemotherapy agent which is used in cancer treatment. This form of cytarabine has more efficacy and fewer side effects relative to the other forms. Since DepoCyt contains the cytarabine encapsulated within phosphatidylcholine and the sterol molecules, we modeled dioleoylphosphatidylcholine (DOPC)/cholesterol bilayer membrane as a carrier for cytarabine to study drug–bilayer interactions. For this purpose, we performed a series of united-atom molecular dynamics (MD) simulations for 25?ns to investigate the interactions between cytarabine and cholesterol-containing DOPC lipid bilayers. Only the uncharged form of cytarabine molecule was investigated. In this study, different levels of the cholesterol content (0, 20, and 40%) were used. MD simulations allowed us to determine dynamical and structural properties of the bilayer membrane and to estimate the preferred location and orientation of the cytarabine molecule inside the bilayer membrane. Properties such as membrane thickness, area per lipid, diffusion coefficient, mass density, bilayer packing, order parameters, and intermolecular interactions were examined. The results show that by increasing the cholesterol concentration in the lipid bilayers, the bilayer thickness increases and area per lipid decreases. Moreover, in accordance with the experiments, our calculations show that cholesterol molecules have ordering effect on the hydrocarbon acyl chains. Furthermore, the cytarabine molecule preferentially occupies the polar region of the lipid head groups to form specific interactions (hydrogen bonds). Our results fully support the experimental data. Our finding about drug–bilayer interaction is crucial for the liposomal drug design.  相似文献   
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