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91.
Linda M. Delahanty Thomas A. Wadden Pamela J. Goodwin Catherine M. Alfano Cynthia A. Thomson Melinda L. Irwin Marian L. Neuhouser Tracy E. Crane Elizabeth Frank Patricia A. Spears Bonnie P. Gillis Dawn L. Hershman Electra D. Paskett Judith Hopkins Vanessa Bernstein Vered Stearns Julia White Clifford Hudis Eric P. Winer Lisa A. Carey Ann H. Partridge Jennifer A. Ligibel 《Obesity (Silver Spring, Md.)》2022,30(1):28-38
92.
93.
Considerable effort has been invested in determining traits underlying invasiveness. Yet, identifying a set of traits that
commonly confers invasiveness in a range of species has proven elusive, and almost nothing is known about genetic loci affecting
invasive success. Incorporating genetic model organisms into ecologically relevant studies is one promising avenue to begin
dissecting the genetic underpinnings of invasiveness. Molecular biologists are rapidly characterizing genes mediating developmental
responses to diverse environmental cues, i.e., genes for plasticity, as well as to environmental factors likely to impose
strong selection on invading species, e.g., resistance to herbivores and competitors, coordination of life-history events
with seasonal changes, and physiological tolerance of heat, drought, or cold. Here, we give an overview of molecular genetic
tools increasingly used to characterize the genetic basis of adaptation and that may be used to begin identifying genetic
mechanisms of invasiveness. Given the divergent traits that affect invasiveness, “invasiveness genes” common to many clades
are unlikely, but the combination of developmental genetic advances with further evolutionary studies and modeling may provide
a framework for identifying genes that account for invasiveness in related species. 相似文献
94.
Morris-Kukoski CL Jagerdeo E Schaff JE LeBeau MA 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,850(1-2):230-235
Detection, identification, and quantitation of ethanol and other low molecular weight volatile compounds in liquid matrices by headspace gas chromatography-flame ionization detection (HS-GC-FID) and headspace gas chromatography-mass spectrometry (HS-GC-MS) are becoming commonly used practices in forensic laboratories. Although it is one of the most frequently utilized procedures, sample preparation is usually done manually. Implementing the use of a dual-rail, programmable autosampler can minimize many of the manual steps in sample preparation. The autosampler is configured so that one rail is used for sample preparation and the other rail is used as a traditional autosampler for sample introduction into the gas chromatograph inlet. The sample preparation rail draws up and sequentially adds a saturated sodium chloride solution and internal standard (0.08%, w/v acetonitrile) to a headspace vial containing a biological sample, a calibrator, or a control. Then, the analytical rail moves the sample to the agitator for incubation, followed by sampling of the headspace for analysis. Using DB-624 capillary columns, the method was validated on a GC-FID and confirmed with a GC-MS. The analytes (ethanol, acetonitrile) and possible interferences (acetaldehyde, methanol, pentane, diethyl ether, acetone, isopropanol, methylene chloride, n-propanol, and isovaleraldehyde) were baseline resolved for both the GC-FID and GC-MS methods. This method demonstrated acceptable linearity from 0 to 1500 mg/dL. The lower limit of quantitation (LOQ) was determined to be 17 mg/dL and the limit of detection was 5 mg/dL. 相似文献
95.
Eberle MA Ng PC Kuhn K Zhou L Peiffer DA Galver L Viaud-Martinez KA Lawley CT Gunderson KL Shen R Murray SS 《PLoS genetics》2007,3(10):1827-1837
Advances in high-throughput genotyping and the International HapMap Project have enabled association studies at the whole-genome level. We have constructed whole-genome genotyping panels of over 550,000 (HumanHap550) and 650,000 (HumanHap650Y) SNP loci by choosing tag SNPs from all populations genotyped by the International HapMap Project. These panels also contain additional SNP content in regions that have historically been overrepresented in diseases, such as nonsynonymous sites, the MHC region, copy number variant regions and mitochondrial DNA. We estimate that the tag SNP loci in these panels cover the majority of all common variation in the genome as measured by coverage of both all common HapMap SNPs and an independent set of SNPs derived from complete resequencing of genes obtained from SeattleSNPs. We also estimate that, given a sample size of 1,000 cases and 1,000 controls, these panels have the power to detect single disease loci of moderate risk (λ ~ 1.8–2.0). Relative risks as low as λ ~ 1.1–1.3 can be detected using 10,000 cases and 10,000 controls depending on the sample population and disease model. If multiple loci are involved, the power increases significantly to detect at least one locus such that relative risks 20%–35% lower can be detected with 80% power if between two and four independent loci are involved. Although our SNP selection was based on HapMap data, which is a subset of all common SNPs, these panels effectively capture the majority of all common variation and provide high power to detect risk alleles that are not represented in the HapMap data. 相似文献
96.
Strengthening the Reporting of Observational Studies in Epidemiology (STROBE): explanation and elaboration 总被引:1,自引:0,他引:1
Vandenbroucke JP von Elm E Altman DG Gøtzsche PC Mulrow CD Pocock SJ Poole C Schlesselman JJ Egger M;STROBE Initiative 《PLoS medicine》2007,4(10):e297
Much medical research is observational. The reporting of observational studies is often of insufficient quality. Poor reporting hampers the assessment of the strengths and weaknesses of a study and the generalisability of its results. Taking into account empirical evidence and theoretical considerations, a group of methodologists, researchers, and editors developed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) recommendations to improve the quality of reporting of observational studies. The STROBE Statement consists of a checklist of 22 items, which relate to the title, abstract, introduction, methods, results and discussion sections of articles. Eighteen items are common to cohort studies, case-control studies and cross-sectional studies and four are specific to each of the three study designs. The STROBE Statement provides guidance to authors about how to improve the reporting of observational studies and facilitates critical appraisal and interpretation of studies by reviewers, journal editors and readers. This explanatory and elaboration document is intended to enhance the use, understanding, and dissemination of the STROBE Statement. The meaning and rationale for each checklist item are presented. For each item, one or several published examples and, where possible, references to relevant empirical studies and methodological literature are provided. Examples of useful flow diagrams are also included. The STROBE Statement, this document, and the associated Web site (http://www.strobe-statement.org/) should be helpful resources to improve reporting of observational research. 相似文献
97.
Marco Lupattelli Paolo Tini Valerio Nardone Cynthia Aristei Simona Borghesi Ernesto Maranzano Paola Anselmo Gianluca Ingrosso Letizia Deantonio Michela Buglione di Monale e Bastia 《Reports of Practical Oncology and Radiotherapy》2022,27(1):15
Brain metastases, the most common metastases in adults, will develop in up to 40% of cancer patients, accounting for more than one-half of all intracranial tumors. They are most associated with breast and lung cancer, melanoma and, less frequently, colorectal and kidney carcinoma.Magnetic resonance imaging (MRI) is the gold standard for diagnosis. For the treatment plan, computed tomography (CT ) images are co-registered and fused with a gadolinium-enhanced T1-weighted MRI where tumor volume and organs at risk are contoured. Alternatively, plain and contrast-enhanced CT scans are co-registered. Single-fraction stereotactic radiotherapy (SRT ) is used to treat patients with good performance status and up to 4 lesions with a diameter of 30 mm or less that are distant from crucial brain function areas. Fractionated SRT (2–5 fractions) is used for larger lesions, in eloquent areas or in proximity to crucial or surgically inaccessible areas and to reduce treatment-related neurotoxicity. The single-fraction SRT dose, which depends on tumor diameter, impacts local control. Fractionated SRT may encompass different schedules. No randomized trial data compared the safety and efficacy of single and multiple fractions. Both single-fraction and fractionated SRT provide satisfactory local control rates, tolerance, a low risk of transient acute adverse events and of radiation necrosis the incidence of which correlated with the irradiated brain volume. 相似文献
98.
Monica Mangoni Simona Borghesi Cynthia Aristei Carlotta Becherini 《Reports of Practical Oncology and Radiotherapy》2022,27(1):57
This paper focuses on the radiobiological mechanisms underlying the effects of stereotactic radiotherapy (SRT ) which, despite SRT expansion, have not yet been fully elucidated. Some authors postulated that radiobiology principles, as applied to conventional fractionations (5R: reoxygenation, repair, repopulation, redistribution, radioresistence), suffice in themselves to account for the excellent clinical results of SRT; others argued that the role of the 5R was limited. Recent preclinical data showed that hypofractionated ablative treatments altered the microenvironment, thus determining cell death either directly or indirectly. Furthermore, dead tumor cells released quantities of antigens, which stimulated antitumor immunity, thus reducing the risk of relapse and metastasis. Better understanding of the radiobiological mechanisms underlying response to high-dose radiation treatment is essential for predicting its short- and long-term effects on the tumor and surrounding healthy tissues and, consequently, for improving its related therapeutic index. 相似文献
99.
Henry S. Kahn Qiuping Gu Kai McKeever Bullard David S. Freedman Namanjeet Ahluwalia Cynthia L. Ogden 《PloS one》2014,9(10)
Background
The sagittal abdominal diameter (SAD) measured in supine position is an alternative adiposity indicator that estimates the quantity of dysfunctional adipose tissue in the visceral depot. However, supine SAD’s distribution and its association with health risk at the population level are unknown. Here we describe standardized measurements of SAD, provide the first, national estimates of the SAD distribution among US adults, and test associations of SAD and other adiposity indicators with prevalent dysglycemia.Methods and Findings
In the 2011–2012 National Health and Nutrition Examination Survey, supine SAD was measured (“abdominal height”) between arms of a sliding-beam caliper at the level of the iliac crests. From 4817 non-pregnant adults (age ≥20; response rate 88%) we used sample weights to estimate SAD’s population distribution by sex and age groups. SAD’s population mean was 22.5 cm [95% confidence interval 22.2–22.8]; median was 21.9 cm [21.6–22.4]. The mean and median values of SAD were greater for men than women. For the subpopulation without diagnosed diabetes, we compared the abilities of SAD, waist circumference (WC), and body mass index (BMI, kg/m2) to identify prevalent dysglycemia (HbA1c ≥5.7%). For age-adjusted, logistic-regression models in which sex-specific quartiles of SAD were considered simultaneously with quartiles of either WC or BMI, only SAD quartiles 3 (p<0.05 vs quartile 1) and 4 (p<0.001 vs quartile 1) remained associated with increased dysglycemia. Based on continuous adiposity indicators, analyses of the area under the receiver operating characteristic curve (AUC) indicated that the dysglycemia model fit for SAD (age-adjusted) was 0.734 for men (greater than the AUC for WC, p<0.001) and 0.764 for women (greater than the AUC for WC or BMI, p<0.001).Conclusions
Measured inexpensively by bedside caliper, SAD was associated with dysglycemia independently of WC or BMI. Standardized SAD measurements may enhance assessment of dysfunctional adiposity. 相似文献100.
Koziol-White CJ Goncharova EA Cao G Johnson M Krymskaya VP Panettieri RA 《Biochimica et biophysica acta》2012,1822(10):1638-1642
Airway diseases such as asthma, emphysema, and chronic bronchitis are, in part, characterized by reversible airflow obstruction and inflammation. In severe disease, marked decreases in lung function are associated with airway smooth muscle proliferation and airway neutrophilia. Inhaled glucocorticoids attenuate increased airflow obstruction and airway inflammation that occur, in part, due to increased smooth muscle migration and proliferation, as well as the airway neutrophilia. Glucocorticoids, however, have adverse side effects and, in some patients, are ineffective despite high doses. Recent research has explored the effects of non-traditional steroids on attenuation of inflammation associated with airway diseases. These non-traditional steroids have improved side effect profiles in comparison to glucocorticoid therapy. Our studies assessed effects of dehydroepiandrosterone-3-sulfate (DHEA-S) on migration of both human peripheral blood neutrophils (PMN) and human airway smooth muscle cells (HASM). DHEA-S dose-dependently inhibited chemotaxis of PMN and HASM while having no effect on the phosphorylation levels of Akt, ERK1/2, p38 MAPK or PKC, canonical positive regulators of cell migration. These studies demonstrate direct effects of DHEA-S on cell migration, thereby suggesting that DHEA-S may attenuate airway inflammation and cell migration. 相似文献