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To study genetic evolution of Moroccan influenza A(H1N1)pdm09 virus strains, we conducted a molecular characterization of the hemagglutinin gene subunit 1 (HA1) of 36 influenza A(H1N1)pdm09 virus strains. The stains were collected from patients in Rabat and Casablanca during two influenza seasons 2009–2010 and 2010–2011. Nucleotide and amino acid sequences of 14 influenza A(H1N1)pdm09 virus strains from 2009 to 2010 were ~97 and 99 %, respectively, similar to the reference strain A/California/07/2009 (H1N1). Phylogenetic analysis of 22 influenza A(H1N1)pdm09 virus strains from 2010 to 2011 revealed a co-circulation of three well-described different genetic groups. Most important, none of the identified groups showed significant changes at the antigenic site of the virus HA1 subunit which may alter the efficacy of California/07/2009 (H1N1) vaccine.  相似文献   
33.
Barriers to accessing legal abortion services in Tunisia are increasing, despite a liberal abortion law, and women are often denied wanted legal abortion services. In this paper, we seek to explore the reasons for abortion denial and whether these reasons had a legal or medical basis. We also identify barriers women faced in accessing abortion and make recommendations for improved access to quality abortion care. We recruited women immediately after they had been turned away from legal abortion services at two facilities in Tunis, Tunisia. Thirteen women consented to participate in qualitative interviews two months after they were turned away from the facility. Women were denied abortion care on the day they were recruited due to three main reasons: gestational age, health conditions, and logistical barriers. Nine women ultimately terminated their pregnancies at another facility, and four women carried to term. None of the women attempted illegal abortion services or self-induction. Further research is needed in order to assess abortion denial from the perspective of providers and medical staff.  相似文献   
34.
The mechanisms determining the host range of Xanthomonas are still undeciphered, despite much interest in their potential roles in the evolution and emergence of plant pathogenic bacteria. Xanthomonas citri pv. citri (Xci) is an interesting model of host specialization because of its pathogenic variants: pathotype A strains infect a wide range of Rutaceous species, whereas pathotype A*/AW strains have a host range restricted to Mexican lime (Citrus aurantifolia) and alemow (Citrus macrophylla). Based on a collection of 55 strains representative of Xci worldwide diversity assessed by amplified fragment length polymorphism (AFLP), we investigated the distribution of type III effectors (T3Es) in relation to host range. We examined the presence of 66 T3Es from xanthomonads in Xci and identified a repertoire of 28 effectors, 26 of which were shared by all Xci strains, whereas two (xopAG and xopC1) were present only in some A*/AW strains. We found that xopAG (=avrGf1) was present in all AW strains, but also in three A* strains genetically distant from AW, and that all xopAG‐containing strains induced the hypersensitive response (HR) on grapefruit and sweet orange. The analysis of xopAD and xopAG suggested horizontal transfer between X. citri pv. bilvae, another citrus pathogen, and some Xci strains. A strains were genetically less diverse, induced identical phenotypic responses and possessed indistinguishable T3E repertoires. Conversely, A*/AW strains exhibited a wider genetic diversity in which clades correlated with geographical origin and T3E repertoire, but not with pathogenicity, according to T3E deletion experiments. Our data outline the importance of taking into account the heterogeneity of Xci A*/AW strains when analysing the mechanisms of host specialization.  相似文献   
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Peritoneal carcinomatosis is common in advanced pancreatic cancer. Despite current standard treatment, patients with this disease until recently were considered incurable. Cancer gene therapy using oncolytic viruses have generated much interest over the past few years. Here, we investigated a new gene directed enzyme prodrug therapy (GDEPT) approach for an oncosuppressive virotherapy strategy using parvovirus H1 (PV-H1) which preferentially replicates and kills malignant cells. Although, PV-H1 is not potent enough to destroy tumors, it represents an attractive vector for cancer gene therapy. We therefore sought to determine whether the suicide gene/prodrug system, yCD/5-FC could be rationally combined to PV-H1 augmenting its intrinsic oncolytic activity for pancreatic cancer prevention and treatment. We showed that the engineered recombinant parvovirus rPVH1-yCD with 5-FC treatment increased significantly the intrinsic cytotoxic effect and resulted in potent induction of apoptosis and tumor growth inhibition in chemosensitive and chemoresistant cells. Additionally, the suicide gene-expressing PV-H1 infection reduced significantly the constitutive activities of NFκB and Akt/PI3K. Combination of their pharmacological inhibitors (MG132 and LY294002) with rPVH1-yCD/5-FC resulted in substantial increase of antitumor activity. In vivo, high and sustained expression of NS1 and yCD was observed in the disseminated tumor nodules and absent in normal tissues. Treatment of mice bearing intraperitoneal pancreatic carcinomatosis with rPVH1-yCD/5-FC resulted in a drastic inhibition of tumor cell spreading and subsequent increase in long-term survival. Together, the presented data show the improved oncolytic activity of wPV-H1 by yCD/5-FC and thus provides valuable effective and promising virotherapy strategy for prevention of tumor recurrence and treatment. In the light of this study, the suicide gene parvovirotherapy approach represents a new weapon in the war against pancreatic cancer. Moreover, these preliminary accomplishments are opening new field for future development of new combined targeted therapies to have a meaningful impact on advanced cancer.  相似文献   
37.
Smallpox (variola virus) is a bioweapon concern. Monkeypox is a growing zoonotic poxvirus threat. These problems have resulted in extensive efforts to develop potential therapeutics that can prevent or treat potentially lethal poxvirus infections in humans. Monoclonal antibodies (mAbs) against smallpox are a conservative approach to this problem, as the licensed human smallpox vaccine (vaccinia virus, VACV) primarily works on the basis of protective antibody responses against smallpox. Fully human mAbs (hmAbs) against vaccinia H3 (H3L) and B5 (B5R), targeting both the mature virion (MV) and extracellular enveloped virion (EV) forms, have been developed as potential therapeutics for use in humans. Post-exposure prophylaxis was assessed in both murine and rabbit animal models. Therapeutic efficacy of the mAbs was assessed in three good laboratory practices (GLP) studies examining severe combined immunodeficiency mice (SCID) given a lethal VACV infection. Pre-exposure combination hmAb therapy provided significantly better protection against disease and death than either single hmAb or vaccinia immune globulin (VIG). Post-exposure combination mAb therapy provided significant protection against disease and death, and appeared to fully cure the VACV infection in ≥50% of SCID mice. Therapeutic efficacy was then assessed in two rabbit studies examining post-exposure hmAb prophylaxis against rabbitpox (RPXV). In the first study, rabbits were infected with RPVX and then provided hmAbs at 48 hrs post-infection, or 1 hr and 72 hrs post-infection. Rabbits in both groups receiving hmAbs were 100% protected from death. In the second rabbitpox study, 100% of animal treated with combination hmAb therapy and 100% of animals treated with anti-B5 hmAb were protected. These findings suggest that combination hmAb treatment may be effective at controlling smallpox disease in immunocompetent or immunodeficient humans.  相似文献   
38.
The purpose of the present study was to determine the effect of natural mediators on the stability of the Trametes trogii crude laccase in the process of decolourization of textile effluents. Acetosyringone allowed the highest wastewaters decolourization rate of 25%. At higher concentrations of acetosyringone, the relative activity of laccase decreased approximately by between 38% and 88% after 5 days of incubation. T. trogii laccase was strongly inactivated at 3 mM syringaldehyde, after 3 days of incubation. However, laccase activity is more stable in the presence of the vanillin and m-coumarate. The T. trogii growth on solid effluent-based-medium was examined and evaluated by measuring the colony diameter in cm. T. trogii was completely inhibited on 100:0 and 80:20 effluent:water solid medium, however, colony diameter reached 5 cm on 60:40 effluent:water solid medium after 13-14 days incubation. When the textile effluent was pre-treated with laccase and laccase-acetosyringone system, the colony diameter of 2 cm of T. trogii on 80:20 effluent:water solid medium was reached after 14 and 10 days of incubation respectively.  相似文献   
39.
Hyperthermia is a cancer treatment modality in which body tissue is exposed to elevated temperatures to destroy cancerous cells. Hyperthermia treatment planning refers to the use of computational models to optimize the heating protocol with the goal of isolating thermal damage to predetermined treatment areas. This paper presents an algorithm to optimize a hyperthermia treatment protocol using the conjugate gradient method with the adjoint problem. The output of the minimization algorithm is a heating protocol that will cause a desired amount of thermal damage. The transient temperature distribution in a cylindrical region is simulated using the bioheat transfer equation. Temperature and time are integrated to calculate the extent of thermal damage in the region via a first-order rate process based on the Arrhenius equation. Several validation experiments are carried out by applying the results of the minimization algorithm to an albumen tissue phantom. Comparisons of metrics describing the damage region (the height and radius of the volume of thermally ablated phantom) show good agreement between the desired extent of damage and the measured extent of damage. The sensitivity of the bioheat transfer model and the Arrhenius damage model to their constituent parameters is calculated to create a tolerable range of error between the desired and measured extent of damage. The measured height and radius of the ablated region fit well within the tolerable range of error found in the sensitivity analysis.  相似文献   
40.
The coupling of growth of the o-demethylating bacterium, Clostridium methoxybenzovorans SR3, with a nitrate-reducing bacterium able to degrade aromatic compounds, Thauera sp. Cin3,4, allowed complete mineralization of poorly oxidizable methoxylated aromatic compounds such as vanillate, isovanillate, vanilline, anisate, ferulate and veratrate. C. methoxybenzovorans o-demethylated these aromatic compounds to their corresponding hydroxylated derivatives and fermented the side chains to acetate and butyrate. The hydroxylated compounds and the fermentation end-products in the C. methoxybenzovorans spent growth medium were then completely metabolized to CO2 on inoculation with the Thauera strain. Kinetic studies with veratrate indicated that C. methoxybenzovorans initially o-demethylated the substrate to vanillate and then further to protocatechuate together with the production of acetate and butyrate from the demethylated side chains. Protocatechuate, acetate and butyrate were then utilized as a carbon source by the Thauera strain aerobically or anaerobically in the presence of nitrate. The results therefore suggest that mono- or dimethoxylated aromatic compounds can be completely mineralized by coupling the growth of a fermentative bacterium with a nitrate-reducing bacterium, and a metabolic pathway for this is proposed.  相似文献   
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