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991.
992.
In order to increase the acceptance rate of early detection testing for prostate cancer, a qualitative prostate-specific antigen (PSA) one-step test has been developed. Determining the PSA level with this test system takes 10 min. The blood samples of 190 men were tested in this qualitative assay, which uses 50 microl of EDTA whole blood and in which the results are ascertained visually. Parallel samples were tested in serum-based, quantitative assays (Abbott Imx, EIA). The findings of the two kinds of assays were compared and evaluated regarding their correspondence (<4.0 and > or = 4.0 ng/ml). For the 74 blood samples in which the quantitative assay showed PSA levels <4.0 ng/ml, the PSA one-step test showed 83.8% correct negative results (corresponds to diagnostic specificity). For the 116 samples in which the classic assay showed PSA levels > or = 4.0 ng/ml, the one-step test showed 90.5% correct positive results (sensitivity). The noted deviations appear especially around the cut-off value of 4.0 ng/ml, i.e. within the PSA concentration range of 3.0 < 4.0 and 4.0 < 5.0 ng/ml. The qualitative PSA one-step test presented here demonstrates good reproducibility. It can be conducted by the patient and is easy to use. The test offers a simple, feasible method for early detection programs for prostate cancer. Copyright Copyright 1999 S. Karger AG, Basel 相似文献
993.
Dendritic cells (DCs) are pivotal for antigen presentation, T-cell priming and B-cell functions. Few studies have been carried out on DCs in human diseases, partly because the current procedures used for DC preparation include elaborate negative selection with monoclonal antibodies (MoAb) and prolonged culture in cytokine-enriched milieu, which may influence DC functions. Using physical density and their adherent properties, DCs were prepared from the blood of healthy subjects. Approximately 2% of human blood mononuclear cells (MNC) were shown to consist of DCs, yielding DCs of 80-90% purity. They expressed markers related to DCs (CD1a, CD11c, CD32 and CD83), costimulatory molecules (CD40, CD80, CD86), human leucocyte antigen (HLA) class I and II molecules and inducible nitric oxide (NO) synthase (NOS2), and lacked lymphocyte and monocyte markers (CD3, CD19, CD20, CD56 and CD14). Compared with blood MNC and T cells, DCs showed a high level of spontaneous proliferation and nitric oxide production, as well as strong proliferative responses in mixed leucocyte reactions. Enzyme-linked immunospot (ELISPOT) assays revealed higher levels of interleukin (IL)-4-, IL-10- and interferon-gamma (IFN-gamma)-secreting cells among DCs than among MNC or T cells obtained from the same blood specimens, while levels of tumour necrosis factor-alpha (TNF-alpha)- and IL-6-secreting cells did not differ. The results demonstrate that the method used is fast, effective and competitively priced, and should be useful for studies of DCs in disease states. 相似文献
994.
Trends in the association of poverty with overweight among US adolescents, 1971-2004 总被引:3,自引:0,他引:3
Context Prevalence of adolescent overweight in the United States has increased substantially during the past 3 decades. Whether socioeconomic disparities in adolescent overweight increased, decreased, or remained constant during this period is not known. Objective To examine trends in adolescent overweight from 1971 to 2004 by family poverty status, as well as trends in potentially relevant eating and physical activity behaviors. Design, Setting, and Participants Four cross-sectional, nationally representative surveys (US National Health and Nutrition Examination Surveys [NHANES] of 1971-1974, 1976-1980, 1988-1994, and 1999-2004) were examined for trends in the prevalence of overweight among adolescents aged 12 to 17 years by family poverty status. Main Outcome Measures Prevalence of adolescent overweight, defined as body mass index at or above the 95th percentile for age and sex in the 2000 Centers for Disease Control and Prevention growth charts. Intermediate outcomes were physical inactivity in the past 30 days, proportion of caloric intake from sweetened beverages (24-hour recall), and whether respondent skipped breakfast (24-hour recall). Results Trends in the association of adolescent overweight with family poverty differed by age stratum (P = .01). In 12- to 14-year-old adolescents, prevalence did not significantly differ by family poverty status in any of the surveys; however, among non-Hispanic black adolescents, overweight prevalence increased faster in nonpoor vs poor families. In contrast, a widening disparity that disfavored adolescents from poor families was present in the 15- to 17-year-old adolescents. This trend was similar among male, female, non-Hispanic white, and non-Hispanic black adolescents, resulting in an overall prevalence of overweight in 1999-2004 more than 50% higher among adolescents in poor vs nonpoor families (23.3% vs 14.4%, respectively; P<.001). Additional analyses suggest that physical inactivity, sweetened beverage consumption, and skipping breakfast may contribute to these disparities. Conclusions Trends of increasing overweight showed a greater impact in families living below the poverty line vs not living below the poverty line among older (15-17 years) but not younger (12-14 years) adolescents. Furthermore, physical inactivity, high consumption of sweetened beverages, and breakfast skipping may be candidate targets for prevention programs aimed at reducing this recently emerged disparity. 相似文献
995.
Rattner BA McKernan MA Eisenreich KM Link WA Olsen GH Hoffman DJ Knowles KA McGowan PC 《Journal of toxicology and environmental health. Part A》2006,69(3-4):331-351
A recent Canada goose (Branta canadensis) die-off at a petroleum refinery fly ash pond in Delaware was attributed to vanadium (V) toxicity. Because of the paucity of V toxicity data for wild birds, a series of studies was undertaken using the forms of V believed to have resulted in this incident. In 7-d single oral dose trials with mallard drakes (Anas platyrhynchos), the estimated median lethal dose (LD50) for vanadium pentoxide was 113 mg/kg body weight, while the LD50 for sodium metavanadate was 75.5 mg/kg. Sodium metavanadate was found to be even more potent (LD50 = 37.2 mg/kg) in male Canada geese. The most distinctive histopathological lesion of both forms of V was lympho-granulocytic enteritis with hemorrhage into the intestinal lumen. Vanadium accumulation in liver and kidney was proportional to the administered dose, and predictive analyses based on these data suggest that V concentrations of 10 microg/g dry weight (dw) in liver and 25 microg/g dw in kidney are associated with mortality (>90% confidence that exposure is >LD50) in mallards acutely exposed to sodium metavanadate. Chronic exposure to increasing dietary concentrations of sodium metavanadate (38.5 to 2651 ppm) over 67 d resulted in V accumulation in liver and kidney (25.2 and 13.6 microg/g dw, respectively), mild intestinal hemorrhage, blood chemistry changes, and evidence of hepatic oxidative stress in mallards, although some of these responses may have been confounded by food avoidance and weight loss. Dietary exposure of mallards to 250 ppm sodium metavanadate for 4 wk resulted in modest accumulation of V in liver and kidney (<5 microg/g dw) and mild intestinal hemorrhage. Based on these data and other observations, it is unlikely that chronic low-level dietary exposure to V poses a direct lethal hazard to wildlife. However, point sources, such as the V-laden fly ash pond encountered by geese at the petroleum refinery in Delaware, may pose a significant hazard to water birds. 相似文献
996.
997.
Rich DQ Mittleman MA Link MS Schwartz J Luttmann-Gibson H Catalano PJ Speizer FE Gold DR Dockery DW 《Environmental health perspectives》2006,114(1):120-123
OBJECTIVES: We reported previously that 24-hr moving average ambient air pollution concentrations were positively associated with ventricular arrhythmias detected by implantable cardioverter defibrillators (ICDs). ICDs also detect paroxysmal atrial fibrillation episodes (PAF) that result in rapid ventricular rates. In this same cohort of ICD patients, we assessed the association between ambient air pollution and episodes of PAF. DESIGN: We performed a case-crossover study. PARTICIPANTS: Patients who lived in the Boston, Massachusetts, metropolitan area and who had ICDs implanted between June 1995 and December 1999 (n=203) were followed until July 2002. EVALUATIONS/MEASUREMENTS: We used conditional logistic regression to explore the association between community air pollution and 91 electrophysiologist-confirmed episodes of PAF among 29 subjects. RESULTS: We found a statistically significant positive association between episodes of PAF and increased ozone concentration (22 ppb) in the hour before the arrhythmia (odds ratio=2.08; 95% confidence interval=1.22, 3.54; p=0.001). The risk estimate for a longer (24-hr) moving average was smaller, thus suggesting an immediate effect. Positive but not statistically significant risks were associated with fine particles, nitrogen dioxide, and black carbon. CONCLUSIONS: Increased ambient O3 pollution was associated with increased risk of episodes of rapid ventricular response due to PAF, thereby suggesting that community air pollution may be a precipitant of these events. 相似文献
998.
The ongoing interest in ethanolamide derivatives of anti-inflammatory drugs as potential synthetic cannabinoids and mechanistic tools for the study of cannabinoid and vanilloid receptors prompted us to develop a practical gram scale synthesis for the hitherto unknown ethanolamide of fenbufen. Dehydration of fenbufen leads to intramolecular ring closure yielding bright pink crystals of the intramolecular enol ester. Reaction of this activated but stable intermediate with ethanolamine leads to the title compound in good yield and purity without the necessity to remove coupling reagents or residual activating groups, such as N, N-dialkyl ureas and fluorinated phenols. 相似文献
999.
Gabrio T Broser S Felder-Kennel A Fichtner G Kirsch H Link B Maisner V Rzonca E Schick KH Schrimpf M Schröder S Spöker-Maas K Weidner U Wuthe J Zöllner I 《Gesundheitswesen (Bundesverband der Arzte des Offentlichen Gesundheitsdienstes (Germany))》2004,66(8-9):528-535
So far there have been rather few reliable and comparable data available on indoor pollution with mould. Following the publication of the Federal Environmental Agency and the Health Agency Baden-Württemberg which supports the assessment of mould pollution of indoor air, it seemed advisable to investigate as to how far these criteria can be used for the assessing the mould pollution in daily practice. The results of investigations of 130 homes and 117 classrooms in Baden-Württemberg. will be represented. 相似文献
1000.
Intraocular pressure in zebrafish: comparison of inbred strains and identification of a reduced melanin mutant with raised IOP 总被引:2,自引:0,他引:2
Link BA Gray MP Smith RS John SW 《Investigative ophthalmology & visual science》2004,45(12):4415-4422
PURPOSE: The goal was to establish an accurate method for measuring intraocular pressure (IOP) in living adult zebrafish and to determine the average IOPs of genetically different strains and mutants. The overall purpose was to develop the zebrafish system for studies of IOP and glaucoma. Elevated IOP and anterior segment dysgenesis are two known risk factors for glaucoma. Because albino mammals have increased IOP and are prone to anterior segment anomalies, the study was focused on a reduced melanin zebrafish mutant, brass. METHODS: Servo-null electrophysiology was used to measure IOP in anesthetized adult zebrafish. A pulled-glass microelectrode was used to penetrate the cornea into the anterior chamber, and pressure transduction was recorded. IOP, histology, and visual behavioral assays were used to assess the brass mutant. RESULTS: Significant differences in IOP were detected between genetically distinct zebrafish strains. IOP averages were highest in the long fin (LF) strain (20.5 +/- 1.2 mm Hg) and lowest in the Oregon AB (AB) strain (10.8 +/- 0.3 mm Hg). In brass mutants, which show a reduced melanin phenotype, IOPs were elevated and mild iris hypoplasia was noted. No defects were observed within the retina or in visual function. CONCLUSIONS: In the present study, an accurate method was developed for measuring IOP in adult zebrafish. Both the ability to measure IOP in the genetically powerful zebrafish model and the conservation of elevated IOP and anterior segment anomalies between albino mammals and hypopigmented fish are important. They strongly support the use of zebrafish for studying the complex genetics of elevated IOP and glaucoma. 相似文献