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151.
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Background

To operationalize the post-MDG agenda, there is a need to evaluate the effects of health interventions on equity. The aim of this study is to evaluate the effect on equity in neonatal survival of the NeoKIP trial (ISRCTN44599712), a population-based, cluster-randomized intervention trial with facilitated local stakeholder groups for improved neonatal survival in Quang Ninh province in northern Vietnam.

Methods

Semi-structured interviews were conducted with all mothers experiencing neonatal mortality and a random sample of 6% of all mothers with a live birth in the study area during the study period (July 2008-June 2011). Multilevel regression analyses were performed, stratifying mothers according to household wealth, maternal education and mother’s ethnicity in order to assess impact on equity in neonatal survival.

Findings

In the last year of study the risk of neonatal death was reduced by 69% among poor mothers in the intervention area as compared to poor mothers in the control area (OR 0.31, 95% CI 0.15–0.66). This pattern was not evident among mothers from non-poor households. Mothers with higher education had a 50% lower risk of neonatal mortality if living in the intervention area during the same time period (OR 0.50, 95% CI 0.28–0.90), whereas no significant effect was detected among mothers with low education.

Interpretation

The NeoKIP intervention promoted equity in neonatal survival based on wealth but increased inequity based on maternal education.  相似文献   
154.

Background

Replicating smallpox vaccines can cause severe complications in individuals with atopic dermatitis (AD). Prior studies evaluating Modified Vaccinia Ankara virus (MVA), a non-replicating vaccine in humans, showed a favorable safety and immunogenicity profile in healthy volunteers.

Objective

This Phase II study compared the safety and immunogenicity of MVA enrolling groups of 350 subjects with AD (SCORAD ≤ 30) and 282 healthy subjects.

Methods

Subjects were vaccinated twice with MVA, each dose given subcutaneously 4 weeks apart. Adverse events, cardiac parameters, and the development of vaccinia virus humoral immune responses were monitored.

Results

The overall safety of the vaccine was similar in both groups. Adverse events affecting skin were experienced significantly more often in subjects with AD, but the majority of these events were mild to moderate in intensity. Seroconversion rates and geometric mean titers for total and neutralizing vaccinia-specific antibodies in the AD group were non-inferior compared to the healthy subjects.

Limitations

The size of the study population limited the detection of serious adverse events occurring at a frequency less than 1%.

Conclusion

MVA has a favorable safety profile and the ability to elicit vaccinia-specific immune responses in subjects with AD.

Trial Registration

ClinicalTrials.gov NCT00316602  相似文献   
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To guide control policies, it is important that the determinants of influenza transmission are fully characterized. Such assessment is complex because the risk of influenza infection is multifaceted and depends both on immunity acquired naturally or via vaccination and on the individual level of exposure to influenza in the community or in the household. Here, we analyse a large household cohort study conducted in 2007–2010 in Vietnam using innovative statistical methods to ascertain in an integrative framework the relative contribution of variables that influence the transmission of seasonal (H1N1, H3N2, B) and pandemic H1N1pdm09 influenza. Influenza infection was diagnosed by haemagglutination-inhibition (HI) antibody assay of paired serum samples. We used a Bayesian data augmentation Markov chain Monte Carlo strategy based on digraphs to reconstruct unobserved chains of transmission in households and estimate transmission parameters. The probability of transmission from an infected individual to another household member was 8% (95% CI, 6%, 10%) on average, and varied with pre-season titers, age and household size. Within households of size 3, the probability of transmission from an infected member to a child with low pre-season HI antibody titers was 27% (95% CI 21%–35%). High pre-season HI titers were protective against infection, with a reduction in the hazard of infection of 59% (95% CI, 44%–71%) and 87% (95% CI, 70%–96%) for intermediate (1∶20–1∶40) and high (≥1∶80) HI titers, respectively. Even after correcting for pre-season HI titers, adults had half the infection risk of children. Twenty six percent (95% CI: 21%, 30%) of infections may be attributed to household transmission. Our results highlight the importance of integrated analysis by influenza sub-type, age and pre-season HI titers in order to infer influenza transmission risks in and outside of the household.  相似文献   
157.
Essential oils from the leaf and twig of Polyalthia suberosa (Roxb.) Thwaites were analyzed using GC/MS/FID. A total of sixty-three constituents were namely identified accounting for 96.03 and 94.12 % in the hydrodistilled oils of the leaf and twig, respectively. Monoterpenes, monoterpenoids, sesquiterpenes, and sesquiterpenoids were characteristic derivatives of P. suberosa essential oils. Sesquiterpenes bicyclogermacrene (26.26 %) and (E)-caryophyllene (7.79 %), and monoterpene β-pinene (12.71 %) were the major constituents of the leaf oil. Sesquiterpenes (E)-caryophyllene (17.17 %) and α-humulene (9.55 %), sesquiterpenoid caryophyllene oxide (9.41 %), and monoterpenes camphene (8.16 %) and tricyclene (6.35 %) were to be main components in the twig oil. The leaf oil indicated cytotoxic activity against three cancer cell lines HepG2, MCF7 and A549 with the IC50 values of 60.96–69.93 μg/mL, while the twig oil inhibited MCF7 with the IC50 value of 66.70 μg/mL. Additionally, the twig oil successfully suppressed the growth of the negative Gram bacterium Pseudomonas aeruginosa, fungus Aspergillus niger, and yeast Candida albicans with the same MIC value of 50 μg/mL, whereas the leaf oil had the same result on the negative Gram bacterium Escherichia coli.  相似文献   
158.
A gene coding for an endoglucanase (EglA), of the glycosyl hydrolase family 12 and derived from Aspergillus niger VTCC-F021, was cloned and sequenced. The cDNA sequence, 717 bp, and its putative endoglucanase, a 238 aa protein with a predicted molecular mass of 26 kDa and a pI of 4.35, exhibited 98.3-98.7% and 98.3-98.6% identities, respectively, with cDNA sequences and their corresponding endoglucanases from Aspergillus niger strains from the GenBank. The cDNA was overexpressed in Pichia pastoris GS115 under the control of an AOX1 promoter with a level of 1.59 U/ml culture supernatant, after 72 h of growth in a YP medium induced with 1% (v/v) of methanol. The molecular mass of the purified EglA, determined by SDS-PAGE, was 33 kDa, with a specific activity of 100.16 and 19.91 U/mg toward 1% (w/v) of beta-glucan and CMC, respectively. Optimal enzymatic activity was noted at a temperature of 55°C and a pH of 5. The recombinant EglA (rEglA) was stable over a temperature range of 30- 37°C and at pH range of 3.5-4.5. Metal ions, detergents, and solvents tested indicated a slightly inhibitory effect on rEglA activity. Kinetic constants (K(m), V(max), k(cat), and k(cat)/ K(m)) determined for rEglA with beta-glucan as a substrate were 4.04 mg/ml, 102.04 U/mg, 2,040.82 min-1, and 505.05, whereas they were 10.17 mg/ml, 28.99 U/mg, 571.71 min-1, and 57.01 with CMC as a substrate, respectively. The results thus indicate that the rEglA obtained in this study is highly specific toward beta-glucan. The biochemical properties of rEglA make it highly valuable for downstream biotechnological applications, including potential use as a feed enzyme.  相似文献   
159.

Background

The social amoebae (Dictyostelia) are a diverse group of Amoebozoa that achieve multicellularity by aggregation and undergo morphogenesis into fruiting bodies with terminally differentiated spores and stalk cells. There are four groups of dictyostelids, with the most derived being a group that contains the model species Dictyostelium discoideum.

Results

We have produced a draft genome sequence of another group dictyostelid, Dictyostelium purpureum, and compare it to the D. discoideum genome. The assembly (8.41 × coverage) comprises 799 scaffolds totaling 33.0 Mb, comparable to the D. discoideum genome size. Sequence comparisons suggest that these two dictyostelids shared a common ancestor approximately 400 million years ago. In spite of this divergence, most orthologs reside in small clusters of conserved synteny. Comparative analyses revealed a core set of orthologous genes that illuminate dictyostelid physiology, as well as differences in gene family content. Interesting patterns of gene conservation and divergence are also evident, suggesting function differences; some protein families, such as the histidine kinases, have undergone little functional change, whereas others, such as the polyketide synthases, have undergone extensive diversification. The abundant amino acid homopolymers encoded in both genomes are generally not found in homologous positions within proteins, so they are unlikely to derive from ancestral DNA triplet repeats. Genes involved in the social stage evolved more rapidly than others, consistent with either relaxed selection or accelerated evolution due to social conflict.

Conclusions

The findings from this new genome sequence and comparative analysis shed light on the biology and evolution of the Dictyostelia.
  相似文献   
160.
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