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1.
A preliminary investigation has been performed (a) to determine the kinetics of bone ingrowth into porous materials and to determine if this ingrowth could be catalyzed by the presence of a foreign substrate; and (b) to measure the bonding capability of bone with a porous-surfaced metallic implant. Tests on porous-surfaced implants corroborate the work of other investigators in showing that bony tissue will grow into a porous substance that has pores large enough to support tissue nourishment. The shear strength of the bone-implant interface appears to increase with pore size and time of healing. Furthermore, it may be possible to catalyze this tissue ingrowth by the introduction into the fracture site of a foreign substance; in this experiment, glass beads 200-290mu in diameter were used. 相似文献
2.
Measurement of blood-retinal barrier permeability: a reproducibility study in normal eyes 总被引:3,自引:0,他引:3
P S Chahal P J Chowienczyk E M Kohner 《Investigative ophthalmology & visual science》1985,26(7):977-982
Fluorescein penetration into the posterior vitreous depends on plasma-free fluorescein concentration and blood-retinal barrier (BRB) permeability. The reproducibility of two methods of deriving BRB permeability was studied in 19 normal eyes of 14 subjects using vitreous fluorophotometry on two separate occasions. Plasma-free fluorescence was measured at intervals over 1 hr and posterior vitreous fluorescence was measured before (background scan), within 6 min (bolus) and at 60 min (measurement) after intravenous fluorescein (14 mg X kg-1). A computer algorithm subtracted background fluorescence from the measurement scan which was then corrected for signal spread by using a "spread" function derived from the bolus scan. BRB permeability coefficient and vitreous diffusion coefficients were derived by fitting a mathematical model to the plasma and corrected vitreous fluorescence data. A permeability index was also calculated by dividing the area under the vitreous fluorescence by the area under the plasma fluorescence curve. There were no significant differences in the results between right and left eyes. Mean +/- SD values on first and second occasions for all eyes were permeability coefficient: (1.91 +/- 0.94) and (2.08 +/- 0.95) X 10(-7) cm X s-1; diffusion coefficient: (1.33 +/- 0.68) and (1.19 +/- 0.54) X 10(-5) cm2 X s-1; and permeability index: (2.05 +/- 1.03) and (2.11 +/- 1.02) X 10(-7) cm X s-1.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
3.
Simran Dhunna Valerie Tarasuk 《Canadian journal of public health. Revue canadienne de santé publique》2021,112(5):888
ObjectivesTo understand the differential vulnerability to household food insecurity of the Black population as compared with white counterparts in Canada.MethodsUsing data for households with Black and white respondents in pooled Canadian Community Health Survey cycles from 2005 to 2014, the 18-question Household Food Security Survey Module was analyzed (N = 491,400). Bivariate and multivariate logistic and multinomial regression models were run using respondent’s race, immigration status, and six well-established predictors of household food insecurity in the general population. Additional multivariable logistic regression models were run, with race interacted with each predictor individually to yield predicted probabilities.ResultsThe weighted prevalence of household food insecurity was 10.0% for white respondents and 28.4% for Black respondents. The odds of Black households being food-insecure as compared with white households fell from 3.56 (95% CI: 3.30–3.85) to 1.88 (95% CI: 1.70–2.08) with adjustment for household socio-demographic characteristics. In contrast with white households, there was relative homogeneity of risk of food insecurity among Black subgroups defined by immigration status, household composition, education, and province of residence. Homeownership was associated with lower probabilities of food insecurity for Black and white households, but the probability among Black owners was similar to that for white renters (14.7% vs. 14.3%). Black households had significantly higher predicted probabilities of food insecurity than their white counterparts across all main sources of household income except child benefits and social assistance.ConclusionBeing racialized as Black appears to be an overriding factor shaping vulnerability to food insecurity for the Black population in Canada. Future research and public policy on food insecurity should seriously consider the role of racism at the systemic and institutional levels. 相似文献
4.
International Urology and Nephrology - 相似文献
5.
6.
Leontiou CA Gueorguiev M van der Spuy J Quinton R Lolli F Hassan S Chahal HS Igreja SC Jordan S Rowe J Stolbrink M Christian HC Wray J Bishop-Bailey D Berney DM Wass JA Popovic V Ribeiro-Oliveira A Gadelha MR Monson JP Akker SA Davis JR Clayton RN Yoshimoto K Iwata T Matsuno A Eguchi K Musat M Flanagan D Peters G Bolger GB Chapple JP Frohman LA Grossman AB Korbonits M 《The Journal of clinical endocrinology and metabolism》2008,93(6):2390-2401
7.
Prognostic Significance of Cavitary Lung Nodules in Granulomatosis With Polyangiitis (Wegener's): A Clinical Imaging Study of 225 Patients 下载免费PDF全文
Bailey Russell Sindu Mohan Rachandeep Chahal Simon Carette Christian Pagnoux 《Arthritis care & research》2018,70(7):1082-1089
Objective
Granulomatosis with polyangiitis (Wegener's) (GPA) is a systemic necrotizing vasculitis in which pulmonary nodules are a common manifestation. Our study examined whether pulmonary nodules, and nodule type (solid versus cavitary), are associated with different disease manifestations and outcomes.Methods
Demographic, clinical, biologic, and radiologic data at diagnosis and during followup and treatments of GPA patients followed at the Mount Sinai Hospital (Canada) Vasculitis Clinic were analyzed. Patients were separated by the absence of lung nodules, presence of solid nodules only, and presence of cavitary nodules (+/? solid nodules). The study outcomes included followup lung imaging, relapses, and deaths.Results
Of 225 patients with GPA, 46 had solid nodules only and 44 had cavitary nodules at diagnosis. Demographic and clinical manifestations were similar in the patient subgroups at diagnosis. Cyclophosphamide (CYC) was used for induction after diagnosis in 76.7% of patients with cavitary nodules, compared with 64.7% of patients without nodules and 51.1% of patients with solid nodules (P = 0.04). The mean ± SD followup after diagnosis was 106.6 ± 92.6 months, and 6 of the patients died. In multivariable analysis, diagnosis before 2000 or pulmonary nodule cavitation at diagnosis were associated with relapse, with a hazard ratio of 0.38 (95% confidence interval [95% CI] 0.22–0.65; P < 0.001) and 1.53 (95% CI 1.00–2.33; P = 0.05), respectively, after adjustment for CYC use.Conclusion
The presence of cavitary nodules led to increased use of CYC but had no impact on survival. Relapse occurred more often, however, in patients with cavitary nodules than in those with solid nodules or no nodules, and should be studied in other cohorts.8.
A Novel KCNJ13 Nonsense Mutation and Loss of Kir7.1 Channel Function Causes Leber Congenital Amaurosis (LCA16) 下载免费PDF全文
Bikash R. Pattnaik Nathaniel York Simran Brar John Chiang De‐Ann M. Pillers Elias I. Traboulsi 《Human mutation》2015,36(7):720-727
Mutations in the KCNJ13 gene that encodes the inwardly rectifying potassium channel Kir7.1 cause snowflake vitreoretinal degeneration (SVD) and leber congenital amaurosis (LCA). Kir7.1 controls the microenvironment between the photoreceptors and the retinal pigment epithelium (RPE) and also contributes to the function of other organs such as uterus and brain. Heterologous expressions of the mutant channel have suggested a dominant‐negative loss of Kir7.1 function in SVD, but parallel studies in LCA16 have been lacking. Herein, we report the identification of a novel nonsense mutation in the second exon of the KCNJ13 gene that leads to a premature stop codon in association with LCA16. We have determined that the mutation results in a severe truncation of the Kir7.1 C‐terminus, alters protein localization, and disrupts potassium currents. Coexpression of the mutant and wild‐type channel has no negative influence on the wild‐type channel function, consistent with the normal clinical phenotype of carrier individuals. By suppressing Kir7.1 function in mice, we were able to reproduce the severe LCA electroretinogram phenotype. Thus, we have extended the observation that Kir7.1 mutations are associated with vision disorders to include novel insights into the molecular mechanism of disease pathobiology in LCA16. 相似文献
9.
John J. Sim Simran K. Bhandari Michael Batech Aviv Hever Teresa N. Harrison Yu-Hsiang Shu Dean A. Kujubu Tracy Y. Jonelis Michael H. Kanter Steven J. Jacobsen 《Mayo Clinic proceedings. Mayo Clinic》2018,93(2):167-178
Objective
To compare renal function decline, incident end-stage renal disease (ESRD), and mortality among patients with 5 common glomerular diseases in a large diverse population.Patients and Methods
A retrospective cohort study (between January 1, 2000, and December 31, 2011) of patients with glomerulonephropathy using the electronic health record of an integrated health system was performed. Estimated glomerular filtration rate (eGFR) change, incident ESRD, and mortality were compared among patients with biopsy-proven focal segmental glomerulosclerosis (FSGS), membranous glomerulonephritis (MN), minimal change disease (MCD), immunoglobulin A nephropathy (IgAN), and lupus nephritis (LN). Competing risk models were used to estimate hazard ratios for different glomerulonephropathies for incident ESRD, with mortality as a competing outcome after adjusting for potential confounders.Results
Of the 2350 patients with glomerulonephropathy (208 patients [9%] younger than 18 years) with a mean follow-up of 4.5±3.6 years, 497 (21%) progressed to ESRD and 195 (8%) died before ESRD. The median eGFR decline was 1.0 mL/min per 1.73 m2 per year but varied across different glomerulonephropathies (P<.001). The highest ESRD incidence (per 100 person-years) was observed in FSGS 8.72 (95% CI, 3.93-16.72) followed by IgAN (4.54; 95% CI, 1.37-11.02), LN (2.38; 95% CI, 0.37-7.82), MN (2.15; 95% CI, 0.29-7.46), and MCD (1.67; 95% CI, 0.15-6.69). Compared with MCD, hazard ratios (95% CIs) for incident ESRD were 3.43 (2.32-5.08) and 2.35 (1.46-3.81), 1.28 (0.79-2.07), and 1.02 (0.62-1.68) for FSGS, IgAN, LN, and MN, respectively. No significant association between glomerulonephropathy types and mortality was detected (P=.24).Conclusion
Our findings from a real-world clinical environment revealed significant differences in eGFR decline and ESRD risk among patients with 5 glomerulonephropathies. These variations in presentation and outcomes warrant different management strategies and expectations. 相似文献10.