全文获取类型
收费全文 | 117477篇 |
免费 | 26232篇 |
国内免费 | 94篇 |
专业分类
耳鼻咽喉 | 1753篇 |
儿科学 | 4668篇 |
妇产科学 | 943篇 |
基础医学 | 18965篇 |
口腔科学 | 5551篇 |
临床医学 | 15057篇 |
内科学 | 27997篇 |
皮肤病学 | 7728篇 |
神经病学 | 15929篇 |
特种医学 | 2935篇 |
外国民族医学 | 5篇 |
外科学 | 17333篇 |
综合类 | 228篇 |
一般理论 | 37篇 |
预防医学 | 5918篇 |
眼科学 | 1819篇 |
药学 | 6885篇 |
6篇 | |
中国医学 | 1059篇 |
肿瘤学 | 8987篇 |
出版年
2023年 | 133篇 |
2022年 | 273篇 |
2021年 | 1918篇 |
2020年 | 6554篇 |
2019年 | 12523篇 |
2018年 | 10521篇 |
2017年 | 11838篇 |
2016年 | 12491篇 |
2015年 | 12324篇 |
2014年 | 12396篇 |
2013年 | 13277篇 |
2012年 | 5485篇 |
2011年 | 5512篇 |
2010年 | 9827篇 |
2009年 | 5966篇 |
2008年 | 3258篇 |
2007年 | 2248篇 |
2006年 | 2238篇 |
2005年 | 1977篇 |
2004年 | 1988篇 |
2003年 | 1899篇 |
2002年 | 1898篇 |
2001年 | 986篇 |
2000年 | 862篇 |
1999年 | 483篇 |
1998年 | 258篇 |
1997年 | 240篇 |
1996年 | 197篇 |
1995年 | 193篇 |
1994年 | 148篇 |
1993年 | 150篇 |
1992年 | 174篇 |
1991年 | 163篇 |
1990年 | 137篇 |
1989年 | 125篇 |
1988年 | 115篇 |
1987年 | 124篇 |
1986年 | 115篇 |
1985年 | 114篇 |
1984年 | 152篇 |
1983年 | 132篇 |
1982年 | 159篇 |
1981年 | 145篇 |
1980年 | 150篇 |
1979年 | 102篇 |
1978年 | 98篇 |
1977年 | 102篇 |
1976年 | 112篇 |
1975年 | 79篇 |
1974年 | 78篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
941.
Analyzing treatment aggressiveness and identifying high‐risk patients in diabetic foot ulcer return to care
下载免费PDF全文
![点击此处可从《Wound repair and regeneration》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Austin C. Remington BA Tina Hernandez‐Boussard PhD Nicholus M. Warstadt BS Micaela A. Finnegan BA Robyn Shaffer BA Jereen Z. Kwong BA Catherine Curtin MD 《Wound repair and regeneration》2016,24(4):731-736
Rates of diabetes and its associated comorbidities have been increasing in the United States, with diabetic foot ulcer treatment representing a large cost to the patient and healthcare system. These ulcers often result in multiple hospital admissions. This study examined readmissions following inpatient care for a diabetic foot ulcer and identified modifiable factors associated with all‐cause 30‐day readmissions to the inpatient or emergency department (ED) setting. We hypothesized that patients undergoing aggressive treatment would have lower 30‐day readmission rates. We identified patient discharge records containing International Classification of Disease ninth revision codes for both diabetes mellitus and distal foot ulcer in the State Inpatient and Emergency Department databases from the Agency for Healthcare Research and Quality, Healthcare Cost and Utilization Project in Florida and New York, 2011–2012. All‐cause 30‐day return to care visits (ED or inpatient) were analyzed. Patient demographics and treatment characteristics were evaluated using univariate and multivariable regression models. The cohort included 25,911 discharges, having a mean age of 63 and an average of 3.8 comorbidities. The overall rate of return to care was 30%, and 21% of subjects underwent a toe or midfoot amputation during their index stay. The most common diagnosis codes upon readmission were diabetes mellitus (19%) and infection (13%). Patients with a toe or midfoot amputation procedure were less likely to be readmitted within 30 days (odds ratio: 0.78; 95% confidence interval: 0.73, 0.84). Presence of comorbidities, black and Hispanic ethnicities, and Medicare and Medicaid payer status were also associated with higher odds of readmission following initial hospitalization (p < 0.05). The study suggests that there are many factors that affect readmission rates for diabetic foot ulcer patients. Understanding patients at high‐risk for readmission can improve counseling and treatment strategies for this fragile patient population. 相似文献
942.
Ana Flávia Marçal Pessoa PhD Juliana Costa Florim MSc Hosana Gomes Rodrigues PhD Vinicius Andrade‐Oliveira PhD Simone A. Teixeira PhD Kaio Fernando Vitzel PhD Rui Curi PhD Niels Olsen Saraiva Câmara PhD Marcelo N. Muscará PhD Marcelo Lazzaron Lamers PhD Marinilce Fagundes Santos PhD 《Wound repair and regeneration》2016,24(6):981-993
Oxidative stress aggravates several long‐term complications in diabetes mellitus. We evaluated the effectiveness of the oral administration of antioxidants (vitamins E and C, 40 and 100 mg/kg b.w., respectively) on skin wound healing acceleration in alloxan‐induced diabetic mice. Mice were wounded 30 days after the induction of diabetes. Antioxidants were effective in preventing oxidative stress, as assessed by TBARS. The enzymes catalase, glutathione reductase, glutathione peroxidase, and superoxide dismutase were increased in diabetics on the 3rd day post‐wounding; catalase and glutathione peroxidase remained still augmented in diabetics after 14th day postwounding, and the treatment with vitamins restored their activities to control. After 3 days, diabetic mice showed lower infiltration of inflammatory cells (including CD11b+ and Ly6G+ cells) and reduced levels of KC, TNF‐α, IL‐1β, and IL‐12 p40 when compared with control mice. The treatment restored cytokine levels. After 14 days, diabetic mice showed late wound closure, persistent inflammation and delayed reepithelialization, accompanied by an increase in MIG+/CD206? macrophages whereas CD206+/MIG? macrophages were decreased. Cytokines IL‐12p40, TNF‐α, IL‐1β, and KC were increased and normal levels were restored after treatment with antioxidants. These results suggest that oxidative stress plays a major role in diabetic wound healing impairment and the oral administration of antioxidants improves healing by modulating inflammation and the antioxidant system with no effect on glycemia. 相似文献
943.
Julien Rigal Thomas Thelen Fergus Byrne Arnaud Cogniet Louis Boissière Stephane Aunoble Jean-Charles Le Huec 《European spine journal》2016,25(4):1000-1005
Introduction
The modern literature is producing a rapidly growing number of articles which highlight the relationship between infection and lumbar disc degeneration. However, the means by which samples are collected is questionable. Posterior approach surgery is not free from skin contamination. The possibility of intraoperative contamination of disc biopsies cannot be excluded.Objective
The objective of this study was to determine if an association existed between lumbar disc degeneration and chronic infection of the intervertebral disc.Materials and methods
313 patients (186/127, F/M) with chronic low back pain secondary to degenerative disc disease which was resistant to medical treatment were included in a single-centre prospective study. All underwent a lumbar anterior video-assisted minimally invasive fusion or disc prosthesis in L4–L5 and/or L5–S1 via an anterior retroperitoneal approach. The patients MRI scans demonstrated in Pfirrmann's classification grade IV or V disc degeneration; 385 disc drives were taken. In terms of Modic changes, 303 Modic 1, 58 Modic II and 24 absence of Modic change, respectively. All underwent intraoperative biopsy, performed according to a strict aseptic protocol. The biopsies were then cultured for 4 weeks with specialised enrichment cultures and subjected to histopathological analysis.Results
The mean age was 47 ± 8.6 years sterile cultures were obtained in 379 samples (98.4 %) and 6 were positive (1.6 %). The cultured bacteria were: Propionibacterium acnes (n:2), Staphylococcus epidermidis (n:2), Citrobacter freundii (n:1), and Saccharopolyspora hirsuta (n:1). Histopathological analysis did not demonstrate any evidence of a neutrophilia. There were no delayed or secondary infections.Discussion and conclusion
Unlike the posterior approach where contamination is common, the anterior video-assisted approach allows a biopsy without skin contact. This approach to the spine is the most effective way to eliminate the risk of contamination. Our results confirm the absence of any relationship between infection and disc degeneration. We suggest that the 6 positive samples in our study may be related to contamination. The absence of infection at 1-year followup is an additional argument in favour of our results. In conclusion, our study shows no association between infection and disc degeneration. The pathophysiology of disc degeneration is complex, but the current literature opens new perspectives.944.
Risk Factors Associated With Early Invasive Pulmonary Aspergillosis in Kidney Transplant Recipients: Results From a Multinational Matched Case–Control Study
下载免费PDF全文
![点击此处可从《American journal of transplantation》网站下载免费的PDF全文](/ch/ext_images/free.gif)
F. Lpez‐Medrano J. T. Silva M. Fernndez‐Ruiz P. L. Carver C. van Delden E. Merino M. J. Prez‐Saez M. Montero J. Coussement M. de Abreu Mazzolin C. Cervera L. Santos N. Sab A. Scemla E. Cordero L. Cruzado‐Vega P. L. Martín‐Moreno
. Len E. Rudas A. Ponce de Len M. Arriola R. Lauzurica M. David C. Gonzlez‐Rico F. Henríquez‐Palop J. Fortún M. Nucci O. Manuel J. R. Pao‐Pardo M. Montejo P. Muoz B. Snchez‐Sobrino A. Mazuecos J. Pascual J. P. Horcajada T. Lecompte C. Lumbreras A. Moreno J. Carratal M. Blanes D. Hernndez E. A. Hernndez‐Mndez M. C. Farias M. Perell‐Carrascosa J. M. Morales A. Andrs J. M. Aguado 《American journal of transplantation》2016,16(7):2148-2157
Risk factors for invasive pulmonary aspergillosis (IPA) after kidney transplantation have been poorly explored. We performed a multinational case–control study that included 51 kidney transplant (KT) recipients diagnosed with early (first 180 posttransplant days) IPA at 19 institutions between 2000 and 2013. Control recipients were matched (1:1 ratio) by center and date of transplantation. Overall mortality among cases was 60.8%, and 25.0% of living recipients experienced graft loss. Pretransplant diagnosis of chronic pulmonary obstructive disease (COPD; odds ratio [OR]: 9.96; 95% confidence interval [CI]: 1.09–90.58; p = 0.041) and delayed graft function (OR: 3.40; 95% CI: 1.08–10.73; p = 0.037) were identified as independent risk factors for IPA among those variables already available in the immediate peritransplant period. The development of bloodstream infection (OR: 18.76; 95% CI: 1.04–339.37; p = 0.047) and acute graft rejection (OR: 40.73, 95% CI: 3.63–456.98; p = 0.003) within the 3 mo prior to the diagnosis of IPA acted as risk factors during the subsequent period. In conclusion, pretransplant COPD, impaired graft function and the occurrence of serious posttransplant infections may be useful to identify KT recipients at the highest risk of early IPA. Future studies should explore the potential benefit of antimold prophylaxis in this group. 相似文献
945.
M. Maquart H. Pascalis S. Abdouroihamane M. Roger F. Abdourahime E. Cardinale C. Cêtre‐Sossah 《Transboundary and Emerging Diseases》2016,63(2):e281-e285
Major explosive outbreaks of Rift Valley fever (RVF), an arthropod borne zoonotic disease, occur in humans and animals with significant mortality and economic impact across continental Africa and the Indian Ocean region (Madagascar, the Comoros archipelago). Recently, sporadic human cases have been reported in Mayotte and Grande Comore, two islands belonging to the Comoros archipelago. To identify the hypothetical source of virus introduction in an inter‐epidemic or a post‐epidemic period, a longitudinal survey of livestock was set up in Comorian ruminant populations, known to be susceptible hosts. The phylogeographic genomic analysis has shown that RVF virus (RVFV) detected in a zebu collected in Anjouan in August 2011 seems to be related to the last known epidemic of RVF which occurred in East Africa and Madagascar (2007–2009). This result highlights the fact that RVFV is maintained within local livestock populations and transboundary animal movements from eastern continental Africa to Indian Ocean islands likely result in RVFV crossover. 相似文献
946.
F. J. Conraths C. Sauter‐Louis A. Globig K. Dietze G. Pannwitz K. Albrecht D. Hreth‐Bntgen M. Beer C. Staubach T. Homeier‐Bachmann 《Transboundary and Emerging Diseases》2016,63(1):10-13
Epidemiological outbreak investigations were conducted in highly pathogenic avian influenza virus of the subtype H5N8 (HPAIV H5N8)‐affected poultry holdings and a zoo to identify potential routes of entry of the pathogen via water, feedstuffs, animals, people, bedding material, other fomites (equipment, vehicles etc.) and the presence of wild birds near affected holdings. Indirect introduction of HPAIV H5N8 via material contaminated by infected wild bird seems the most reasonable explanation for the observed outbreak series in three commercial holdings in Mecklenburg‐Western Pomerania and Lower Saxony, while direct contact to infected wild birds may have led to outbreaks in a zoo in Rostock and in two small free‐range holdings in Anklam, Mecklenburg‐Western Pomerania. 相似文献
947.
948.
OBJECT: The Hoffmann sign is commonly used in clinical practice to assess cervical spine disease. It is unknown whether the sign correlates with the severity of myelopathy, and no consensus exists regarding the significance of a positive sign in asymptomatic individuals. METHODS: In a retrospective review of cervical spine surgeries for myelopathy due to cervical spondylosis, ossification of the posterior longitudinal ligament, or disc herniation performed at a tertiary center, the authors compiled data on the presence of hyperreflexia, the Hoffmann and Babinski signs, and modified Japanese Orthopaedic Association (mJOA) scale scores. Then, in a prospective evaluation, new patients with lumbar spine complaints were examined for the presence of a Hoffmann sign, and, if present, a cervical MR imaging study was assessed for cord compression. RESULTS: Of the 225 surgically treated patients, a Hoffmann sign occurred in 68%, hyperreflexia in 60%, and a Babinski sign in 33%. In patients with milder disability (mJOA Scores 14-16), the Hoffmann sign was present in 46%, whereas a Babinski sign occurred in 10%; in those with severe myelopathy and mJOA scores of < or =10, the Hoffmann sign was present in 81% and the Babinski sign in 83%. Of 290 patients presenting exclusively with lumbar spine-related complaints, 36 (12%) had a positive Hoffmann sign. Magnetic resonance imaging demonstrated spinal cord compression in 91% when the sign was present bilaterally and 50% when positive unilaterally. CONCLUSIONS: In patients surgically treated for cervical myelopathy, the Hoffmann sign is more prevalent and more likely to be seen in individuals with less severe neurological deficits than the Babinski sign. In patients with lumbar symptoms, a bilateral Hoffmann sign was a highly sensitive marker for occult cervical cord compression, whereas a unilateral Hoffmann sign correlated with similar disease in about one-half of patients. 相似文献
949.
PTEN抑癌基因在乳腺癌组织中的表达及其与乳腺癌微小转移灶的关系 总被引:1,自引:0,他引:1
目的:研究PTEN抑癌基因在乳腺癌组织中的表达,探讨其与乳腺癌病人的外周血、骨髓及前哨淋巴结微小转移灶之间的关系。方法:选择53例乳腺癌病人的组织标本,用免疫组织化学方法检测原发肿瘤PTEN蛋白的表达;用定量RT鄄PCR法测定原发肿瘤PTENmRNA的表达。以免疫细胞化学法检测外周血和骨髓中的微小转移灶;HE染色和免疫组织化学法检测前哨淋巴结中的微小转移灶。结果:外周血、骨髓及前哨淋巴结中微小转移灶的检出率分别是24.5%,56.6%,26.4%和41.5%。乳腺癌组织中PTEN蛋白表达呈丢失者占35.8%,后者与外周血和骨髓微小转移灶间无显著关系,而与前哨淋巴结中的微小转移密切相关(P≤0.001)。PTENmRNA的表达与外周血、骨髓及前哨淋巴结中的微小转移灶之间均无显著相关性。结论:乳腺癌组织中PTEN蛋白表达的丢失与前哨淋巴结中的微小转移有密切关系,可作为预测其早期转移的重要指标。 相似文献
950.
Schulman CI Cohn SM Blackbourne L Soffer D Hoskins N Bowers N Habib F Crookes B Benjamin B Pizano LR 《The Journal of trauma》2005,59(1):92-95
OBJECTIVE: The purpose of this study was to determine the optimal time interval for identifying a pneumothorax (PTX) on chest radiograph (CXR) after placing a chest tube on water seal. METHODS: One hundred nineteen chest tubes were placed on water seal according to a prospective, observational study protocol. After water seal, both an early (3.1 +/- 2.1 hours) and a late (17.6 +/- 8.0 hours) CXR was obtained. RESULTS: Thirty-one patients had a PTX on follow-up CXRs. There were 22 early and 9 late PTXs identified. Three patients in the early group had a clinically significant PTX or an increase in the size of PTX on follow-up CXR. None of the patients in the late group had a clinically significant PTX (any worsening of their PTX) or required further intervention. CONCLUSION: A normal chest radiograph obtained 3 hours after placing a chest tube on water seal effectively excludes development of a clinically significant pneumothorax. 相似文献