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991.
Cara C. Powers Henry Ho Sarah E. Beykirch Cathy Huynh Robert H. Hopper Jr C. Anderson Engh Jr Charles A. Engh 《The Journal of arthroplasty》2010
The highly cross-linked polyethylene liners currently used with modular uncemented cups have substantially decreased wear and osteolysis at early follow-up. However, retroacetabular osteolysis has still been reported in some cases with DePuy Orthopaedic's (Warsaw, IN) second-generation Duraloc acetabular shell. DePuy's third-generation Pinnacle cup incorporates a different shell-liner locking mechanism. We compared the clinical outcome among a matched series of 42 Duraloc and 42 Pinnacle cups at a mean follow-up of 5.9 years. Although the Harris Hip Scores and wear rates were not statistically different between the 2 cup designs, retroacetabular osteolysis behind the central hole was absent among the Pinnacle cups but noted among 19% of the Duraloc cups. 相似文献
992.
G. L. Chew C. W. Huo D. Huang T. Blick P. Hill J. Cawson H. Frazer M. C. Southey J. L. Hopper K. Britt M. A. Henderson I. Haviv E. W. Thompson 《Breast cancer research and treatment》2014,148(2):303-314
Mammographic density (MD) is a strong risk factor for breast cancer. It is altered by exogenous endocrine treatments, including hormone replacement therapy and Tamoxifen. Such agents also modify breast cancer (BC) risk. However, the biomolecular basis of how systemic endocrine therapy modifies MD and MD-associated BC risk is poorly understood. This study aims to determine whether our xenograft biochamber model can be used to study the effectiveness of therapies aimed at modulating MD, by examine the effects of Tamoxifen and oestrogen on histologic and radiographic changes in high and low MD tissues maintained within the biochamber model. High and low MD human tissues were precisely sampled under radiographic guidance from prophylactic mastectomy fresh specimens of high-risk women, then inserted into separate vascularized murine biochambers. The murine hosts were concurrently implanted with Tamoxifen, oestrogen or placebo pellets, and the high and low MD biochamber tissues maintained in the murine host environment for 3 months, before the high and low MD biochamber tissues were harvested for histologic and radiographic analyses. The radiographic density of high MD tissue maintained in murine biochambers was decreased in Tamoxifen-treated mice compared to oestrogen-treated mice (p = 0.02). Tamoxifen treatment of high MD tissue in SCID mice led to a decrease in stromal (p = 0.009), and an increase in adipose (p = 0.023) percent areas, compared to placebo-treated mice. No histologic or radiographic differences were observed in low MD biochamber tissue with any treatment. High MD biochamber tissues maintained in mice implanted with Tamoxifen, oestrogen or placebo pellets had dynamic and measurable histologic compositional and radiographic changes. This further validates the dynamic nature of the MD xenograft model, and suggests the biochamber model may be useful for assessing the underlying molecular pathways of Tamoxifen-reduced MD, and in testing of other pharmacologic interventions in a preclinical model of high MD. 相似文献
993.
Amos CI Wang LE Lee JE Gershenwald JE Chen WV Fang S Kosoy R Zhang M Qureshi AA Vattathil S Schacherer CW Gardner JM Wang Y Bishop DT Barrett JH;GenoMEL Investigators MacGregor S Hayward NK Martin NG Duffy DL;Q-Mega Investigators Mann GJ Cust A Hopper J;AMFS Investigators Brown KM Grimm EA Xu Y Han Y Jing K McHugh C Laurie CC Doheny KF Pugh EW Seldin MF Han J Wei Q 《Human molecular genetics》2011,20(24):5012-5023
We performed a multistage genome-wide association study of melanoma. In a discovery cohort of 1804 melanoma cases and 1026 controls, we identified loci at chromosomes 15q13.1 (HERC2/OCA2 region) and 16q24.3 (MC1R) regions that reached genome-wide significance within this study and also found strong evidence for genetic effects on susceptibility to melanoma from markers on chromosome 9p21.3 in the p16/ARF region and on chromosome 1q21.3 (ARNT/LASS2/ANXA9 region). The most significant single-nucleotide polymorphisms (SNPs) in the 15q13.1 locus (rs1129038 and rs12913832) lie within a genomic region that has profound effects on eye and skin color; notably, 50% of variability in eye color is associated with variation in the SNP rs12913832. Because eye and skin colors vary across European populations, we further evaluated the associations of the significant SNPs after carefully adjusting for European substructure. We also evaluated the top 10 most significant SNPs by using data from three other genome-wide scans. Additional in silico data provided replication of the findings from the most significant region on chromosome 1q21.3 rs7412746 (P = 6 × 10(-10)). Together, these data identified several candidate genes for additional studies to identify causal variants predisposing to increased risk for developing melanoma. 相似文献
994.
995.
This paper introduces a novel method for measuring the surface temperature of ultrasound transducer membranes and compares it with two standard measurement techniques. The surface temperature rise was measured as defined in the IEC Standard 60601-2-37. The measurement techniques were (i) thermocouple, (ii) thermal camera and (iii) novel infra-red (IR) “micro-sensor.” Peak transducer surface measurements taken with the thermocouple and thermal camera were −3.7 ± 0.7 (95% CI)°C and −4.3 ± 1.8 (95% CI)°C, respectively, within the limits of the IEC Standard. Measurements taken with the novel IR micro-sensor exceeded these limits by 3.3 ± 0.9 (95% CI)°C. The ambiguity between our novel method and the standard techniques could have direct patient safety implications because the IR micro-sensor measurements were beyond set limits. The spatial resolution of the measurement technique is not well defined in the IEC Standard and this has to be taken into consideration when selecting which measurement technique is used to determine the maximum surface temperature. 相似文献
996.
Muller DC Giles GG Manning JT Hopper JL English DR Severi G 《British journal of cancer》2011,105(3):438-440
Background:
The ratio of the lengths of index and ring fingers (2D:4D) is a marker of prenatal exposure to sex hormones, with low 2D:4D being indicative of high prenatal androgen action. Recent studies have reported a strong association between 2D:4D and risk of prostate cancer.Methods:
A total of 6258 men participating in the Melbourne Collaborative Cohort Study had 2D:4D assessed. Of these men, we identified 686 incident prostate cancer cases. Hazard ratios (HRs) and confidence intervals (CIs) were estimated for a standard deviation increase in 2D:4D.Results:
No association was observed between 2D:4D and prostate cancer risk overall (HRs 1.00; 95% CIs, 0.92–1.08 for right, 0.93–1.08 for left). We observed a weak inverse association between 2D:4D and risk of prostate cancer for age <60, however 95% CIs included unity for all observed ages.Conclusion:
Our results are not consistent with an association between 2D:4D and overall prostate cancer risk, but we cannot exclude a weak inverse association between 2D:4D and early onset prostate cancer risk. 相似文献997.
Southey MC Ramus SJ Dowty JG Smith LD Tesoriero AA Wong EE Dite GS Jenkins MA Byrnes GB Winship I Phillips KA Giles GG Hopper JL 《British journal of cancer》2011,104(6):903-909
Background:
Knowing a young woman with newly diagnosed breast cancer has a germline BRCA1 mutation informs her clinical management and that of her relatives. We sought an optimal strategy for identifying carriers using family history, breast cancer morphology and hormone receptor status data.Methods:
We studied a population-based sample of 452 Australian women with invasive breast cancer diagnosed before age 40 years for whom we conducted extensive germline mutation testing (29 carried a BRCA1 mutation) and a systematic pathology review, and collected three-generational family history and tumour ER and PR status. Predictors of mutation status were identified using multiple logistic regression. Areas under receiver operator characteristic (ROC) curves were estimated using five-fold stratified cross-validation.Results:
The probability of being a BRCA1 mutation carrier increased with number of selected histology features even after adjusting for family history and ER and PR status (P<0.0001). From the most parsimonious multivariate model, the odds ratio for being a carrier were: 9.7 (95% confidence interval: 2.6–47.0) for trabecular growth pattern (P=0.001); 7.8 (2.7–25.7) for mitotic index over 50 mitoses per 10 high-powered field (P=0.0003); and 2.7 (1.3–5.9) for each first-degree relative with breast cancer diagnosed before age 60 years (P=0.01).The area under the ROC curve was 0.87 (0.83–0.90).Conclusion:
Pathology review, with attention to a few specific morphological features of invasive breast cancers, can identify almost all BRCA1 germline mutation carriers among women with early-onset breast cancer without taking into account family history. 相似文献998.
Stevens KN Garcia-Closas M Fredericksen Z Kosel M Pankratz VS Hopper JL Dite GS Apicella C Southey MC Schmidt MK Broeks A Van 't Veer LJ Tollenaar RA Fasching PA Beckmann MW Hein A Ekici AB Johnson N Peto J dos Santos Silva I Gibson L Sawyer E Tomlinson I Kerin MJ Chanock S Lissowska J Hunter DJ Hoover RN Thomas GD Milne RL Arias Pérez JI González-Neira A Benítez J Burwinkel B Meindl A Schmutzler RK Bartrar CR Hamann U Ko YD Brüning T Chang-Claude J Hein R Wang-Gohrke S Dörk T Schürmann P 《British journal of cancer》2011,105(12):1934-1939
Background:
Somatic mutations in phosphoinositide-3-kinase catalytic subunit alpha (PIK3CA) are frequent in breast tumours and have been associated with oestrogen receptor (ER) expression, human epidermal growth factor receptor-2 overexpression, lymph node metastasis and poor survival. The goal of this study was to evaluate the association between inherited variation in this oncogene and risk of breast cancer.Methods:
A single-nucleotide polymorphism from the PIK3CA locus that was associated with breast cancer in a study of Caucasian breast cancer cases and controls from the Mayo Clinic (MCBCS) was genotyped in 5436 cases and 5280 controls from the Cancer Genetic Markers of Susceptibility (CGEMS) study and in 30 949 cases and 29 788 controls from the Breast Cancer Association Consortium (BCAC).Results:
Rs1607237 was significantly associated with a decreased risk of breast cancer in MCBCS, CGEMS and all studies of white Europeans combined (odds ratio (OR)=0.97, 95% confidence interval (CI) 0.95–0.99, P=4.6 × 10−3), but did not reach significance in the BCAC replication study alone (OR=0.98, 95% CI 0.96–1.01, P=0.139).Conclusion:
Common germline variation in PIK3CA does not have a strong influence on the risk of breast cancer 相似文献999.
Roberts A Nancarrow D Clendenning M Buchanan DD Jenkins MA Duggan D Taverna D McKeone D Walters R Walsh MD Young BW Jass JR Rosty C Gattas M Pelzer E Hopper JL Goldblatt J George J Suthers GK Phillips K Parry S Woodall S Arnold J Tucker K Muir A Drini M Macrae F Newcomb P Potter JD Pavluk E Lindblom A Young JP 《Familial cancer》2011,10(2):245-254
Causative genetic variants have to date been identified for only a small proportion of familial colorectal cancer (CRC). While conditions such as Familial Adenomatous Polyposis and Lynch syndrome have well defined genetic causes, the search for variants underlying the remainder of familial CRC is plagued by genetic heterogeneity. The recent identification of families with a heritable predisposition to malignancies arising through the serrated pathway (familial serrated neoplasia or Jass syndrome) provides an opportunity to study a subset of familial CRC in which heterogeneity may be greatly reduced. A genome-wide linkage screen was performed on a large family displaying a dominantly-inherited predisposition to serrated neoplasia genotyped using the Affymetrix GeneChip Human Mapping 10?K SNP Array. Parametric and nonparametric analyses were performed and resulting regions of interest, as well as previously reported CRC susceptibility loci at 3q22, 7q31 and 9q22, were followed up by finemapping in 10 serrated neoplasia families. Genome-wide linkage analysis revealed regions of interest at 2p25.2-p25.1, 2q24.3-q37.1 and 8p21.2-q12.1. Finemapping linkage and haplotype analyses identified 2q32.2-q33.3 as the region most likely to harbour linkage, with heterogeneity logarithm of the odds (HLOD) 2.09 and nonparametric linkage (NPL) score 2.36 (P?=?0.004). Five primary candidate genes (CFLAR, CASP10, CASP8, FZD7 and BMPR2) were sequenced and no segregating variants identified. There was no evidence of linkage to previously reported loci on chromosomes 3, 7 and 9. 相似文献
1000.
Whether people who inherit a mutation in MUTYH from only one parent (monoallelic mutation) are at increased risk of colorectal cancer (CRC) remains controversial. Most
previous studies and meta-analyses have not found statistically significant associations but, given carriers are relatively
rare, may be underpowered to detect small increased risks. We have conducted a systematic review and meta-regression analysis
of previously published case–control studies to estimate the strength of association for monoallelic MUTYH mutation and CRC risk. Potential sources of heterogeneity were evaluated. We have compared the carrier frequency in cases
with a family history of CRC to that of controls, as a novel and powerful design, to measure statistical evidence of an association
but not the strength of association. The magnitude of the genotype-disease association, estimated from a pooled odds ratio
comparing cases unselected for family history with controls, was 1.15 (95% CI = 0.98–1.36) and not substantially altered by
adjustment for potential sources of heterogeneity. Monoallelic mutation carrier frequency was greater for cases ascertained
due to a family history (3.3%; SE 0.9%) than for controls (1.4%; SE 0.3%) (P = 0.02). Monoallelic MUTYH mutation carriers are at increased risk of CRC but the average increase is small. 相似文献