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981.
Lenice de Castro Muniz de Quadros Luciana de Avila Quevedo Janaína Vieira dos Santos Motta André Carraro Felipe Garcia Ribeiro Bernardo Lessa Horta Denise Petrucci Gigante 《PloS one》2015,10(10)
This study aimed to evaluate the relationship between mental disorders at 30 years of age and social mobility by formally testing three hypotheses: Risk Accumulation; Critical Period; and Social Mobility. The study was performed using data from the 30-year follow-up of the Pelotas Birth Cohort Study, conducted in 1982, and data from previous follow-ups. The tool used to evaluate mental health was the Self Report Questionnaire (SRQ-20). For the statistical analysis, the chi-square test with the Yates correction was used to estimate the prevalence of mental disorder, and the Poisson regression with robust variance was used to formally test the hypotheses according to the Risk Accumulation, Critical Period and Social Mobility Models. The analyses were stratified by gender. The prevalence of Common Mental Disorders (CMDs) was 24.3% (95% CI 22.9–25.7) when the whole sample was considered. The highest prevalence, 27.1% (95% CI 25.1–29.2), was found in women, and the difference between genders was significant (p < 0.001). CMDs were more frequent in participants who remained “poor” in the three follow-ups. In both men and women, the best fit was obtained with the Risk Accumulation Model, with p = 0.6348 and p = 0.2105, respectively. The results indicate the need to rethink public income maintenance policies. Finally, we suggest further studies to investigate the role of different public policies in decreasing the prevalence of mental disorders and thus contribute proposals of new policies that may contribute to the prevention of these disorders. 相似文献
982.
983.
Vimentin-derived proteins : Differences between normal human fibroblasts and transformed human cells 总被引:3,自引:0,他引:3
Two-dimensional gel electrophoresis revealed a quantitative difference in a series of polypeptides ranging in MW from 45 000 to 51 000 and of lower isoelectric pH than vimentin, when comparing normal human fibroblasts with a virally transformed subline and with HeLa cells. Re-extraction of purified [35S]vimentin with cold whole cell homogenates and peptide mapping showed that these polypeptides are derivatives of vimentin. They may be natural components of a normal fibroblast's architecture or they may arise from a pool of vimentin that is not structured within intermediate filaments at the time of extraction. Furthermore, we show that vimentin from the two transformed cell types is more resistant to proteolysis by whole cell homogenates than vimentin from normal fibroblasts. Structural alteration of vimentin may play an important role in the expression of transformation. 相似文献
984.
Recombination is a prominent feature of meiosis in which it plays an important role in increasing genetic diversity during inheritance. Additionally, in most organisms, recombination also plays mechanical roles in chromosomal processes, most notably to mediate pairing of homologous chromosomes during prophase and, ultimately, to ensure regular segregation of homologous chromosomes when they separate at the first meiotic division. Recombinational interactions are also subject to important spatial patterning at both early and late stages. Recombination-mediated processes occur in physical and functional linkage with meiotic axial chromosome structure, with interplay in both directions, before, during, and after formation and dissolution of the synaptonemal complex (SC), a highly conserved meiosis-specific structure that links homolog axes along their lengths. These diverse processes also are integrated with recombination-independent interactions between homologous chromosomes, nonhomology-based chromosome couplings/clusterings, and diverse types of chromosome movement. This review provides an overview of these diverse processes and their interrelationships.The role of the meiotic program is to generate gametes having half the chromosome complement of the original progenitor cell. This task is accomplished by occurrence of a single round of DNA replication followed by two successive rounds of chromosome segregation. Homologs segregate to opposite poles at meiosis I, then sisters separate to opposite poles in meiosis II, analogously to mitosis (Fig. 1A).Open in a separate windowFigure 1.General features of meiosis. (A) At meiosis I, homologs segregate; at meiosis II, sisters segregate. At metaphase I (left), maternal (red) and paternal (black) chromosomes are held together by a chiasma comprising a reciprocal crossover (CO) plus connections along sister arms, which are released during segregation. (B) Monochiasmate bivalent of Locusta after bromodeoxyuridine (BrdU) incorporation. Differential staining of the sister chromatids confirms that exchange has occurred, for example, between red and purple chromatids in corresponding drawings. (From Jones 1987; reprinted, with permission, from Academic Press © 1987.) (C) Diplotene bivalent of grasshopper with three chiasmata (arrows) and corresponding drawing. (From Jones and Franklin 2006; reprinted, with permission, from Elsevier © 2006.) (D) Top: Meiotic prophase in rye microsporocytes; chromosomes are stained by hematoxylin (pictures by D.Z.). Bottom: corresponding timing of the recombination steps from double-strand breaks (DSBs) to COs; timing of intermediates as in budding yeast (Hunter 2007). SEI, Single-end invasion; dHJ, double Holliday junction; SDSA, synthesis-dependent strand annealing; NCO, noncrossover.During meiosis, a central role of recombination is to increase genetic diversity. However, recombination is also essential for two fundamental features unique to meiotic chromosome mechanics: pairing and segregation of homologous chromosomes (“homologs”). Pairing is mediated by the totality of programmed interhomolog recombinational interactions in association with chromosome structural axes (see below). Segregation is mediated specifically by the carefully chosen subset of those interactions that mature into crossover (CO) products. During segregation of homologs, just as for segregation of sister chromatids, the separating entities must be connected to one another such that regular bipolar alignment on the spindle results in tension on centromere/kinetochore complexes. When all segregating pairs are properly aligned and under tension, anaphase is triggered. Segregation of sisters is ensured by connections between sister centromere/kinetochore regions. Segregation of homologs is ensured by connections along chromosome arms that are provided by the combined effects of an interhomolog CO plus links between sisters (Fig. 1A). These connections can be seen cytologically as chiasmata (Fig. 1B,C). In organisms in which meiosis occurs without recombination, other features have evolved that hold homologs together to ensure regular segregation (Zickler and Kleckner 1998, 1999; reviewed in Stewart and Dawson 2008; Tsai and McKee 2011; Lake and Hawley 2012; Obeso et al. 2014). 相似文献
985.
Considerations for the process development of insect‐derived antimicrobial peptide production
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Antimicrobial peptides (AMPs) could evolve into new therapeutic lead molecules against multi‐resistant bacteria. As insects are a rich source of AMP, the identification and characterization of insect‐derived AMPs is particularly emphasized. One challenge of bringing these molecules into market, e.g., as a drug, is to develop a cost‐efficient large‐scale production process. Due to the fact that a direct AMP isolation from insects is not economical and that chemical synthesis is recommended for peptide sizes below 40 amino acids, a viable option is heterologous AMP production. Therefore, previous knowledge concerning the expression of larger proteins can be adapted, but due to the AMP nature (e.g., small size, bactericide) additional challenges have to be faced during up and downstream processing. Nonetheless the bottleneck for large‐scale AMP production is the same as for proteins; mainly the downstream process. This review introduces opportunities for insect‐derived AMP production, like the choice of the expression system (based on previously derived data), depending on the AMP nature, as well as new purification strategies like elastin‐like peptide/intein based purification strategies. All of these aspects are discussed with regard to large‐scale processes and costs. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 31:1–11, 2015 相似文献
986.
Stephen B. Kritchevsky Kristen M. Beavers Michael E. Miller M. Kyla Shea Denise K. Houston Dalane W. Kitzman Barbara J. Nicklas 《PloS one》2015,10(3)
Background
Obesity is associated with increased mortality, and weight loss trials show rapid improvement in many mortality risk factors. Yet, observational studies typically associate weight loss with higher mortality risk. The purpose of this meta-analysis of randomized controlled trials (RCTs) of weight loss was to clarify the effects of intentional weight loss on mortality.Methods
2,484 abstracts were identified and reviewed in PUBMED, yielding 15 RCTs reporting (1) randomization to weight loss or non-weight loss arms, (2) duration of ≥18 months, and (3) deaths by intervention arm. Weight loss interventions were all lifestyle-based. Relative risks (RR) and 95% confidence intervals (95% CI) were estimated for each trial. For trials reporting at least one death (n = 12), a summary estimate was calculated using the Mantel-Haenszel method. Sensitivity analysis using sparse data methods included remaining trials.Results
Trials enrolled 17,186 participants (53% female, mean age at randomization = 52 years). Mean body mass indices ranged from 30–46 kg/m2, follow-up times ranged from 18 months to 12.6 years (mean: 27 months), and average weight loss in reported trials was 5.5±4.0 kg. A total of 264 deaths were reported in weight loss groups and 310 in non-weight loss groups. The weight loss groups experienced a 15% lower all-cause mortality risk (RR = 0.85; 95% CI: 0.73–1.00). There was no evidence for heterogeneity of effect (Cochran’s Q = 5.59 (11 d.f.; p = 0.90); I2 = 0). Results were similar in trials with a mean age at randomization ≥55 years (RR = 0.84; 95% CI 0.71–0.99) and a follow-up time of ≥4 years (RR = 0.85; 95% CI 0.72–1.00).Conclusions
In obese adults, intentional weight loss may be associated with approximately a 15% reduction in all-cause mortality. 相似文献987.
Background
Red cell distribution width (RDW) is a routine laboratory measure associated with poor outcomes in adult critical illness.Objective
We determined the utility of RDW as an early pragmatic biomarker for outcome in pediatric critical illness.Methods
We used multivariable logistic regression to test the association of RDW on the first day of pediatric intensive care unit (PICU) admission with prolonged PICU length of stay (LOS) >48 hours and mortality. The area under the receiver operating characteristic curve (AUROC) for RDW was compared to the Pediatric Index of Mortality (PIM)-2 score.Results
Over a 13-month period, 596 unique patients had RDW measured on the first day of PICU admission. Sepsis was an effect modifier for LOS >48 hours but not mortality. In sepsis, RDW was not associated with LOS >48 hours. For patients without sepsis, each 1% increase in RDW was associated with 1.17 (95% CI 1.06, 1.30) increased odds of LOS >48 hours. In all patients, RDW was independently associated with PICU mortality (OR 1.25, 95% CI 1.09, 1.43). The AUROC for RDW to predict LOS >48 hours and mortality was 0.61 (95% CI 0.56, 0.66) and 0.65 (95% CI 0.55, 0.75), respectively. Although the AUROC for mortality was comparable to PIM-2 (0.75, 95% CI 0.66, 0.83; p = 0.18), RDW did not increase the discriminative utility when added to PIM-2. Despite the moderate AUROC, RDW <13.4% (upper limit of lower quartile) had 53% risk of LOS >48 hours and 3.3% risk of mortality compared to patients with an RDW >15.7% (lower limit of upper quartile) who had 78% risk of LOS >48 hours and 12.9% risk of mortality (p<0.001 for both outcomes).Conclusions
Elevated RDW was associated with outcome in pediatric critical illness and provided similar prognostic information as the more complex PIM-2 severity of illness score. Distinct RDW thresholds best discriminate low- versus high-risk patients. 相似文献988.
Ludmila Correa Muniz Ana Maria Baptista Menezes Maria Cecília Formoso Assun??o Fernando Cesar Wehrmeister Jeovany Martínez-Mesa Helen Gon?alves Marlos Rodrigues Domingues Denise Petrucci Gigante Bernardo Lessa Horta Fernando C. Barros 《PloS one》2015,10(4)
Objective
To evaluate the effect of total breastfeeding, breastfeeding duration and type of breastfeeding at 3 months of age on bone mass at 18 and 30 years.Study Design
A prospective, longitudinal study was conducted with two birth cohorts (1982 and 1993) in Pelotas, Southern Brazil. Measurements of bone mineral content (BMC) and bone mineral density (BMD) at 18 and 30 years of age were obtained by dual-energy X-ray absorptiometry (DXA). Information on breastfeeding was collected during the first 4 years of life. Analyses were performed by linear regression and stratified by sex.Results
A total of 1109 and 3226 participants provided complete information on breastfeeding in early life and bone mass at 18 and 30 years, respectively. No association between breastfeeding and bone mass was observed in women at both ages nor among men at age 30. Among men at the age of 18, BMC and BMD were higher among those breastfed regardless of duration (p=0.032 and p=0.043, respectively).Conclusions
Despite a very weak positive effect of breastfeeding (yes/no) on BMC and BMD at age 18 in men, most findings pointed to a lack of association between breastfeeding and bone mass until young adulthood. 相似文献989.
Pamela A. Dyson Denis Anthony Brenda Fenton Denise E. Stevens Beatriz Champagne Li-Ming Li Jun Lv Jorge Ramírez Hernández K. R. Thankappan David R. Matthews Community Interventions for Health collaboration 《PloS one》2015,10(4)
Background
Non-communicable disease (NCD) is increasing rapidly in low and middle-income countries (LMIC), and is associated with tobacco use, unhealthy diet and physical inactivity. There is little evidence for up-scaled interventions at the population level to reduce risk in LMIC.Methods
The Community Interventions for Health (CIH) program was a population-scale community intervention study with comparator population group undertaken in communities in China, India, and Mexico, each with populations between 150,000-250,000. Culturally appropriate interventions were delivered over 18-24 months. Two independent cross-sectional surveys of a stratified sample of adults aged 18-64 years were conducted at baseline and follow-up.Results
A total of 6,194 adults completed surveys at baseline, and 6,022 at follow-up. The proportion meeting physical activity recommendations decreased significantly in the control group (C) (44.1 to 30.2%), but not in the intervention group (I) (38.0 to 36.1%), p<0.001. Those eating ≥5 portions of fruit and vegetables daily decreased significantly in C (19.2 to 17.2%), but did not change in I (20.0 to 19.6%,), p=0.013. The proportion adding salt to food was unchanged in C (24.9 to 25.3%) and decreased in I (25.9 to 19.6%), p<0.001. Prevalence of obesity increased in C (8.3 to 11.2%), with no change in I (8.6 to 9.7%,) p=0.092. Concerning tobacco, for men the difference-in-difference analysis showed that the reduction in use was significantly greater in I compared to C (p=0.014)Conclusions
Up-scaling known health promoting interventions designed to reduce the incidence of NCD in whole communities in LMIC is feasible, and has measurable beneficial outcomes on risk factors for NCD, namely tobacco use, diet, and physical inactivity. 相似文献990.
Isadora Maria Villas Boas Giselle Pidde-Queiroz Fabio Carlos Magnoli Rute M. Gon?alves-de-Andrade Carmen W. van den Berg Denise V. Tambourgi 《PloS one》2015,10(3)