全文获取类型
收费全文 | 28516篇 |
免费 | 2060篇 |
国内免费 | 108篇 |
专业分类
耳鼻咽喉 | 448篇 |
儿科学 | 1027篇 |
妇产科学 | 452篇 |
基础医学 | 2817篇 |
口腔科学 | 671篇 |
临床医学 | 2673篇 |
内科学 | 6442篇 |
皮肤病学 | 613篇 |
神经病学 | 1504篇 |
特种医学 | 1225篇 |
外国民族医学 | 1篇 |
外科学 | 5569篇 |
综合类 | 398篇 |
一般理论 | 16篇 |
预防医学 | 1463篇 |
眼科学 | 928篇 |
药学 | 2345篇 |
中国医学 | 65篇 |
肿瘤学 | 2027篇 |
出版年
2024年 | 69篇 |
2023年 | 258篇 |
2022年 | 492篇 |
2021年 | 1155篇 |
2020年 | 566篇 |
2019年 | 954篇 |
2018年 | 1147篇 |
2017年 | 728篇 |
2016年 | 781篇 |
2015年 | 796篇 |
2014年 | 1281篇 |
2013年 | 1457篇 |
2012年 | 2173篇 |
2011年 | 2184篇 |
2010年 | 1124篇 |
2009年 | 1003篇 |
2008年 | 1596篇 |
2007年 | 1515篇 |
2006年 | 1430篇 |
2005年 | 1203篇 |
2004年 | 1118篇 |
2003年 | 951篇 |
2002年 | 861篇 |
2001年 | 616篇 |
2000年 | 563篇 |
1999年 | 512篇 |
1998年 | 189篇 |
1997年 | 163篇 |
1996年 | 161篇 |
1995年 | 159篇 |
1994年 | 129篇 |
1993年 | 110篇 |
1992年 | 276篇 |
1991年 | 291篇 |
1990年 | 256篇 |
1989年 | 218篇 |
1988年 | 215篇 |
1987年 | 222篇 |
1986年 | 194篇 |
1985年 | 184篇 |
1984年 | 117篇 |
1983年 | 129篇 |
1982年 | 91篇 |
1981年 | 75篇 |
1980年 | 69篇 |
1979年 | 132篇 |
1978年 | 78篇 |
1977年 | 74篇 |
1974年 | 69篇 |
1973年 | 89篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Hageman JC Patel J Franklin P Miscavish K McDougal L Lonsway D Khan FN 《Diagnostic microbiology and infectious disease》2008,62(4):440-442
A vancomycin-intermediate Staphylococcus aureus (VISA) isolated from the blood of a 46-year-old patient with endocarditis was determined to be pulsed-field type USA300, daptomycin nonsusceptible, and positive for the Panton-Valentine leukocidin genes. Development of the VISA phenotype does not appear limited to traditional health care strains of S. aureus. 相似文献
82.
Amani Kallel Samir Ben Ali Yosra Sediri Sonia Chabrak Monia Elasmi Ha?fa Sanhaji Omar Souheil Sameh Haj-Taieb Moncef Feki Rachid Mechmeche Riadh Jemaa Naziha Kaabachi 《Clinical chemistry and laboratory medicine》2008,46(8):1097-1101
BACKGROUND: Numerous polymorphisms of the apolipoprotein B (APOB) gene have been described. Particularly, the insertion/deletion (Ins/Del) polymorphism located in the coding part of the signal peptide of apoB, associated with modification of lipid concentrations and the risk of coronary artery disease and/or myocardial infarction (MI), has been reported in the general population. Moreover, conflicting results emerge from the literature and suggest that the effect is context-dependent. In the present study, the first investigation of the Ins/Del polymorphism of the APOB gene in Tunisian patients with MI, we examined a possible association between this polymorphism and MI in a subgroup of the Tunisian population. METHODS: A total of 318 Tunisian patients with MI and 368 healthy controls were included in the study. Genomic DNA was extracted from white blood cells, and the Ins/Del polymorphism was determined by electrophoresis in polyacrylamide gels after PCR amplification. A binary logistic regression analysis was performed to test how the association between MI and Ins/Del polymorphism is independent from confounding factors. RESULTS: A significant difference in genotype distribution and allele frequency was observed between patients and controls. Patients with MI had a frequency of 7.2% for the Del/Del genotype, 39.6% for the Ins/Del genotype, and 53.1% for the Ins/Ins genotype. Controls had a frequency of 3.0% for the Del/Del, 32.1% for the Ins/Del and 64.9% for the Ins/Ins genotype (chi2=12.93, p=0.002). The MI patient group showed a significantly higher frequency of the Del allele compared to controls (27.1% vs. 19.1%; chi2=12.50, p=0.0004). In comparison to the Ins/Ins homozygotes, the odds ratio (95% confidence interval) for MI was 1.51 (1.09-2.07) for Ins/Del heterozygotes and 2.95 (1.40-6.22) for Del/Del homozygotes. In multivariate analysis, age (p=0.001), smoking (p<0.001), hypertension (p=0.001), diabetes mellitus (p<0.001), and dyslipidemia (p=0.01) were independent correlates of the presence of MI, whereas the Ins/Del polymorphism (p=0.330) was not an independent predictor of MI. CONCLUSIONS: The present study shows a significant but not independent association between the Ins/Del polymorphism of the APOB gene and MI in the Tunisian population. 相似文献
83.
Kevin Johnson Marcus D. Jarboe George B. Mychaliska Ryan P. Barbaro Peter Rycus Ronald B. Hirschl Samir K. Gadepalli 《Journal of pediatric surgery》2018,53(7):1301-1304
Background
Neurologic complications are common, and amongst the most devastating complications in pediatric patients undergoing extracorporeal life support (ECLS). Carotid artery cannulation (CAN) has been associated with an increase in these complications, thereby shaping practices to avoid this approach in most pediatric patients in which other cannulation approaches are viable.Methods
A retrospective review of children (0–18 years) in the ELSO database was undertaken from 1989 through 2013. Multivariate logistic regression analysis of rates of stroke and other neurologic complications based on cannulation technique was undertaken, adjusting for patient factors including age, underlying disease process, and severity of illness.Results
A total of 30,282 ECLS runs were found in the database. CAN was associated with higher rates of stroke (5.15% vs 3.74%) and overall neurologic complications. However, when correcting for patient factors, including age, underlying disease process, and support type, CAN was not associated with an increased rate of neurologic complications or stroke (p > 0.05 for both).Conclusion
When correcting for patient related factors CAN is not associated with an increase in stroke or neurologic compilcations. CAN should be re-examined as a cannulation technique for older pediatric patients.Level of evidence
III. 相似文献84.
Samir S. Taneja 《The Journal of urology》2018,199(4):892-894
85.
Siamak Daneshmand Sanjay Patel Yair Lotan Kamal Pohar Edouard Trabulsi Michael Woods Tracy Downs William Huang Jeffrey Jones Michael O’Donnell Trinity Bivalacqua Joel DeCastro Gary Steinberg Ashish Kamat Matthew Resnick Badrinath Konety Mark Schoenberg J. Stephen Jones 《The Journal of urology》2018,199(5):1158-1165
86.
Roxana de Fátima Camelo Albuquerque Cinthia Esbrile Moraes Carbonara Rita de Cássia T. Martin Luciene Machado dos Reis Climério Pereira do Nascimento Sérgio Samir Arap Rosa M.A. Moysés Vanda Jorgetti Fábio L.M. Montenegro Rodrigo Bueno de Oliveira 《Surgery》2018,163(2):381-387
Background
Parathyroidectomy (PTx) decreases the mortality rate of refractory secondary hyperparathyroidism (rSHP) due to chronic kidney disease. A consensus regarding which techniques of PTx are associated with better outcomes is not available. The aims of this study are to evaluate the clinical and laboratory evolution of 49 hemodialysis patients with rSHP who underwent PTx using different techniques.Methods
Patients underwent subtotal PTx (sub-PTx) or total PTx with autotransplantation (AT) of 45 (PTx-AT45) or 90 parathyroid fragments (PTx-AT90) and were followed for 12 months. We analyzed the expression of proliferating cell nuclear antigen (PCNA), calcium-sensing receptor (CasR), vitamin D receptor (VDR), fibroblast growth factor receptor-1 (FGFR1), sodium-dependent phosphate cotransporter-1 (PIT1), and Klotho in parathyroid glands.Results
Baseline median serum intact parathyroid hormone (iPTH) levels were 1,466 (1,087–2,125) pg/mL; vascular calcification scores correlated with serum iPTH (r?=?0.529; P?=?.002) and serum phosphate levels (r?=?0.389; P?=?.028); and Klotho expression was negatively correlated with serum phosphate levels (r?=??0.4; P?=?.01). After 12 months, serum iPTH and alkaline phosphatase levels were significantly controlled in all groups, as was bone pain. The proportions of patients with serum iPTH levels within the ranges recommended by Kidney Disease: Improving Global Outcomes were similar among the treatment groups. During the hungry bone disease (HBS), patients received 3,786?g (1,412–7,580) of elemental calcium, and a trend toward a positive correlation between the cumulative calcium load at the end of follow up and VC score post-PTx was noted (r?=?0.390; P?=?.06). Two cases evolved to clinically uncontrolled hyperparathyroidism in the sub-PTx group. The expression patterns of PCNA, VDR, CasR, PIT1, FGFR1, and Klotho in parathyroid glands did not correlate with serum systemic iPTH levels or the duration of HBS.Conclusions
All 3 operative techniques were effective at controlling rSHP, both in clinical and laboratory terms. Neither the quantity nor quality of parathyroid fragments influenced serum systemic iPTH and AT-iPTH levels. The cumulative calcium load appeared to correlate with the VC score and may have affected its progression. The effects of phosphate restriction on Klotho expression in human parathyroid glands and the subsequent decrease in FGF23 resistance must be addressed in further studies. 相似文献87.
88.
Daniel Rhee Barbara Pockaj Nabil Wasif Chee-Chee Stucky Victor Pizzitola Marina Giurescu Bhavika Patel Janice McCarthy Richard Gray 《American journal of surgery》2018,215(1):151-154
Introduction
In-operating room specimen radiography (ORSR) has not been studied among women undergoing radioactive seed localization (RSL) for breast cancer surgery and had the potential to decrease operative time and perhaps improve intraoperative margin management.Methods
One hundred consecutive RSL segmental mastectomies among 98 patients using ORSR were compared to 100 consecutive segmental mastectomies among 98 patients utilizing conventional radiography (CSR) prior to the initiation of ORSR from December 2013 to January 2015 after radioactive seed localization. Final pathologic margins were considered to be 10 mm for all cases of no residual disease after biopsy or neoadjuvant therapy, but such patients were excluded from analyses involving tumor size. All patients' specimens were subjected to intraoperative pathologic consultation in addition to ORSR or CSR.Results
The median age of the cohort was 65 years (range 36–97), and the median tumor size was 1 cm. There were no differences between the ORSR and CSR groups in age, tumor size, percentage of cases with only DCIS, and percentage of cases with microcalcifications. The ORSR group had a statistically significant lower BMI. Mean operative time from cut-to-close was not significantly different (ORSR 77 min, SD 24.8 vs CSR 76 min, SD 24.8, p = 0.75). There was no statistical difference in mean closest final pathologic margin (4.99 mm, SD 3.3 vs 4.88 mm, SD 3.5, p = 0.9). The percentage undergoing intraoperative margin re-excision (ORSR 40%, CR 47%, p = 0.31) and the mean total number of margins excised intraoperatively (ORSR 0.9, CR 1.0 p = 0.65) were similar. The rate of any margin <2 mm was 14% vs 12% for ORSR and CR, respectively (p = 0.64). The mean specimen volume for ORSR was 76cm3 (SD 101.8) vs 90cm3 (SD 61.2) for CSR; this difference was not statistically significant (p = 0.25). The mean ratio of segmental mastectomy volume to maximum tumor diameter was less for ORSR (82.7cm2 vs 139.4cm2, p = 0.014).Conclusion
ORSR for RSL breast surgery, in the setting of routine intraoperative pathology consultation, does not significantly impact operative time, the rate or number of additional intraoperative margins excised, the number of reoperations for margins, or the width of final pathological margins. ORSR was associated with a decrease in the volume of segmental mastectomies relative to the tumor diameter. 相似文献89.