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481.
Bart Victor Meridith Blevins Ann F. Green Elisée Ndatimana Lázaro González-Calvo Edward F. Fischer Alfredo E. Vergara Sten H. Vermund Omo Olupona Troy D. Moon 《PloS one》2014,9(9)
Background
Poverty is a multidimensional phenomenon and unidimensional measurements have proven inadequate to the challenge of assessing its dynamics. Dynamics between poverty and public health intervention is among the most difficult yet important problems faced in development. We sought to demonstrate how multidimensional poverty measures can be utilized in the evaluation of public health interventions; and to create geospatial maps of poverty deprivation to aid implementers in prioritizing program planning.Methods
Survey teams interviewed a representative sample of 3,749 female heads of household in 259 enumeration areas across Zambézia in August-September 2010. We estimated a multidimensional poverty index, which can be disaggregated into context-specific indicators. We produced an MPI comprised of 3 dimensions and 11 weighted indicators selected from the survey. Households were identified as “poor” if were deprived in >33% of indicators. Our MPI is an adjusted headcount, calculated by multiplying the proportion identified as poor (headcount) and the poverty gap (average deprivation). Geospatial visualizations of poverty deprivation were created as a contextual baseline for future evaluation.Results
In our rural (96%) and urban (4%) interviewees, the 33% deprivation cut-off suggested 58.2% of households were poor (29.3% of urban vs. 59.5% of rural). Among the poor, households experienced an average deprivation of 46%; thus the MPI/adjusted headcount is 0.27 ( = 0.58×0.46). Of households where a local language was the primary language, 58.6% were considered poor versus Portuguese-speaking households where 73.5% were considered non-poor. Living standard is the dominant deprivation, followed by health, and then education.Conclusions
Multidimensional poverty measurement can be integrated into program design for public health interventions, and geospatial visualization helps examine the impact of intervention deployment within the context of distinct poverty conditions. Both permit program implementers to focus resources and critically explore linkages between poverty and its social determinants, thus deriving useful findings for evidence-based planning. 相似文献482.
Troy D. Moon Ezequiel B. Ossemane Ann F. Green Elisée Ndatimana Eurico José Charlotte P. Buehler C. William Wester Sten H. Vermund Omo Olupona 《PloS one》2014,9(10)
Objective
To generate maps reflecting the intersection of community-based Voluntary Counseling and Testing (VCT) delivery points with facility-based HIV program demographic information collected at the district level in three districts (Ile, Maganja da Costa and Chinde) of Zambézia Province, Mozambique; in order to guide planning decisions about antiretroviral therapy (ART) program expansion.Methods
Program information was harvested from two separate open source databases maintained for community-based VCT and facility-based HIV care and treatment monitoring from October 2011 to September 2012. Maps were created using ArcGIS 10.1. Travel distance by foot within a 10 km radius is generally considered a tolerable distance in Mozambique for purposes of adherence and retention planning.Results
Community-based VCT activities in each of three districts were clustered within geographic proximity to clinics providing ART, within communities with easier transportation access, and/or near the homes of VCT volunteers. Community HIV testing results yielded HIV seropositivity rates in some regions that were incongruent with the Ministry of Health’s estimates for the entire district (2–13% vs. 2% in Ile, 2–54% vs. 11.5% in Maganja da Costa, and 23–43% vs. 14.4% in Chinde). All 3 districts revealed gaps in regional disbursement of community-based VCT activities as well as access to clinics offering ART.Conclusions
Use of geospatial mapping in the context of program planning and monitoring allowed for characterizing the location and size of each district’s HIV population. In extremely resource limited and logistically challenging settings, maps are valuable tools for informing evidence-based decisions in planning program expansion, including ART. 相似文献483.
In this work, we model the local calcium release from clusters with a few inositol 1,4,5-trisphosphate receptor (IP3R) channels, focusing on the stochastic process in which an open channel either triggers other channels to open (as a puff) or fails to cause any channel to open (as a blip). We show that there are linear relations for the interevent interval (including blips and puffs) and the first event latency against the inverse cluster size. However, nonlinearity is found for the interpuff interval and the first puff latency against the inverse cluster size. Furthermore, the simulations indicate that the blip fraction among all release events and the blip frequency are increasing with larger basal [Ca2+], with blips in turn giving a growing contribution to basal [Ca2+]. This result suggests that blips are not just lapses to trigger puffs, but they may also possess a biological function to contribute to the initiation of calcium waves by a preceding increase of basal [Ca2+] in cells that have small IP3R clusters. 相似文献
484.
In this work, we model the local calcium release from clusters with a few inositol 1,4,5-trisphosphate receptor (IP3R) channels, focusing on the stochastic process in which an open channel either triggers other channels to open (as a puff) or fails to cause any channel to open (as a blip). We show that there are linear relations for the interevent interval (including blips and puffs) and the first event latency against the inverse cluster size. However, nonlinearity is found for the interpuff interval and the first puff latency against the inverse cluster size. Furthermore, the simulations indicate that the blip fraction among all release events and the blip frequency are increasing with larger basal [Ca2+], with blips in turn giving a growing contribution to basal [Ca2+]. This result suggests that blips are not just lapses to trigger puffs, but they may also possess a biological function to contribute to the initiation of calcium waves by a preceding increase of basal [Ca2+] in cells that have small IP3R clusters. 相似文献
485.
Sten M. Wie Tariq S. Adwan James DeGregori Steven M. Anderson Mary E. Reyland 《The Journal of biological chemistry》2014,289(15):10900-10908
Radiation therapy for head and neck cancer can result in extensive damage to normal adjacent tissues such as the salivary gland and oral mucosa. We have shown previously that tyrosine phosphorylation at Tyr-64 and Tyr-155 activates PKCδ in response to apoptotic stimuli by facilitating its nuclear import. Here we have identified the tyrosine kinases that mediate activation of PKCδ in apoptotic cells and have explored the use of tyrosine kinase inhibitors for suppression of irradiation-induced apoptosis. We identify the damage-inducible kinase, c-Abl, as the PKCδ Tyr-155 kinase and c-Src as the Tyr-64 kinase. Depletion of c-Abl or c-Src with shRNA decreased irradiation- and etoposide-induced apoptosis, suggesting that inhibitors of these kinases may be useful therapeutically. Pretreatment with dasatinib, a broad spectrum tyrosine kinase inhibitor, blocked phosphorylation of PKCδ at both Tyr-64 and Tyr-155. Expression of “gate-keeper” mutants of c-Abl or c-Src that are active in the presence of dasatinib restored phosphorylation of PKCδ at Tyr-155 and Tyr-64, respectively. Imatinib, a c-Abl-selective inhibitor, also specifically blocked PKCδ Tyr-155 phosphorylation. Dasatinib and imatinib both blocked binding of PKCδ to importin-α and nuclear import, demonstrating that tyrosine kinase inhibitors can inhibit nuclear accumulation of PKCδ. Likewise, pretreatment with dasatinib also suppressed etoposide and radiation induced apoptosis in vitro. In vivo, pre-treatment of mice with dasatinib blocked radiation-induced apoptosis in the salivary gland by >60%. These data suggest that tyrosine kinase inhibitors may be useful prophylactically for protection of nontumor tissues in patients undergoing radiotherapy of the head and neck. 相似文献
486.
487.
Methods to characterise and confirm specificity of scFv displayed on phages are important during panning procedures, especially when selecting for antibody fragments with weak affinities in the millimole to micromole range. In this report the surface plasmon resonance (SPR) biosensor was used to study and verify specificity of phages displaying weak anti-carbohydrate scFvs. The variable immunoglobulin light (VL) and heavy (VH) chain genes of the weak monoclonal antibody 39.5 were amplified and cloned into a phagemid and displayed as a scFv-pIII fusion protein on filamentous phage. This monoclonal antibody recognises with weak affinity the structural sequence Glcalpha1-4Glc present in a variety of carbohydrate molecules. Injection of the 39.5 phages over a biosensor chip immobilised with a (Glc)4-BSA conjugate confirmed selective binding of the scFv to its antigen. Inhibition studies verified the specificity. These results clearly show that SPR technology can be used to evaluate in terms of binding and specificity weakly interacting scFv displayed on the phage surface. 相似文献
488.
Mancini MC Costa AP de Melo ME Cercato C Giannella-Neto D Garrido AB Rosberg S Albertsson-Wikland K Villares SM Halpern A 《Obesity (Silver Spring, Md.)》2006,14(3):383-387
Objective : The purpose of this study was to analyze growth hormone (GH) concentrations in obese women before and after Roux‐en‐Y gastric bypass (RYGBP) and how resulting changes in weight, fat mass, ghrelin levels, and insulin sensitivity affect GH secretion. Research Methods and Procedures : Blood was sampled at 20‐minute intervals for 24 hours in 10 non‐diabetic premenopausal severely obese women before and 6 months after RYGBP. GH concentrations were measured in all samples, and serum ghrelin was collected at five time‐points. Results : After a 27% BMI drop (55.9 ± 6.2 to 40.7 ± 5.8 kg/m2), blunted GH profiles underwent partial recovery. Basal, postprandial, and mean ghrelin concentrations were not changed. A negative correlation was found between mean GH levels and insulin and homeostasis model assessment (p < 0.01). BMI accounted for 54% of GH variation. Discussion : Partial recovery of GH secretion after RYGBP‐induced weight loss suggests that a blunted secretion is not a causal factor of obesity but a consequence of the obese state and does not seem to be ghrelin‐level dependent. 相似文献
489.
Strahinja Vucic Esther de Vries Paul H.C. Eilers Sten P. Willemsen Mette A.R. Kuijpers Birte Prahl‐Andersen Vincent W.V. Jaddoe Albert Hofman Eppo B. Wolvius Edwin M. Ongkosuwito 《American journal of physical anthropology》2014,155(1):91-98
Many studies have established dental age standards for different populations; however, very few studies have investigated whether dental development is stable over time on a population level. Therefore, the aim of this study was to analyze changes in dental maturity in Dutch children born between 1961 and 2004. We used 2,655 dental panoramic radiographs of 2‐ to 16‐year‐old Dutch children from studies performed in three major cities in the Netherlands. Based on a trend in children born between 1961 and 1994, we predicted that a child of a certain age and gender born in 1963 achieved the same dental maturity on average, 1.5 years later than a child of the same age born 40 years later. After adjusting for the birth year of a child in the analysis, the regression coefficient of the city variable was reduced by 56.6% and it remained statistically significant. The observed trend from 1961 to 1994 was extrapolated to 9‐ to 10‐year‐old children born in 2002–2004, and validation with the other samples of children with the same characteristics showed that 95.9%–96.8% of the children had dental maturity within the 95% of the predicted range. Dental maturity score was significantly and positively associated with the year of birth, gender, and age in Dutch children, indicating a trend in earlier dental development during the observation period, 1961–2004. These findings highlight the necessity of taking the year of birth into account when assessing dental development within a population with a wider time span. Am J Phys Anthropol 155:91–98, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
490.
Vladimir Gogvadze Sten Orrenius Boris Zhivotovsky 《Apoptosis : an international journal on programmed cell death》2009,14(4):624-640
Mitochondrial malfunctioning is implicated in the pathogenesis of a variety of disorders, including cancer and multiple neurodegenerative
diseases, such as Parkinson’s disease, Alzheimer’s disease, amyotrophic lateral sclerosis, and Huntington’s disease. Disturbance
of mitochondrial vital functions, e.g., production of ATP, calcium buffering capacity, and generation of reactive oxygen species,
can be potentially involved in disease pathogenesis. Neurological disorders caused by mitochondrial deterioration are often
associated with cell loss within specific brain regions. In contrast, mitochondrial alterations in tumor cells and the “Warburg
effect” might lead to cell survival and resistance of tumor cells to chemotherapy. This review is devoted to the role of mitochondria
in neurodegeneration and tumor formation, and describes how targeting of mitochondria can be beneficial in the therapy of
these diseases, which affect a large human population. 相似文献