全文获取类型
收费全文 | 8264篇 |
免费 | 514篇 |
国内免费 | 48篇 |
专业分类
耳鼻咽喉 | 98篇 |
儿科学 | 263篇 |
妇产科学 | 155篇 |
基础医学 | 1397篇 |
口腔科学 | 464篇 |
临床医学 | 627篇 |
内科学 | 1811篇 |
皮肤病学 | 215篇 |
神经病学 | 721篇 |
特种医学 | 102篇 |
外科学 | 866篇 |
综合类 | 34篇 |
一般理论 | 4篇 |
预防医学 | 746篇 |
眼科学 | 174篇 |
药学 | 586篇 |
中国医学 | 51篇 |
肿瘤学 | 512篇 |
出版年
2024年 | 6篇 |
2023年 | 65篇 |
2022年 | 162篇 |
2021年 | 314篇 |
2020年 | 203篇 |
2019年 | 248篇 |
2018年 | 314篇 |
2017年 | 189篇 |
2016年 | 234篇 |
2015年 | 241篇 |
2014年 | 380篇 |
2013年 | 494篇 |
2012年 | 721篇 |
2011年 | 749篇 |
2010年 | 411篇 |
2009年 | 311篇 |
2008年 | 601篇 |
2007年 | 545篇 |
2006年 | 505篇 |
2005年 | 438篇 |
2004年 | 423篇 |
2003年 | 406篇 |
2002年 | 348篇 |
2001年 | 43篇 |
2000年 | 35篇 |
1999年 | 45篇 |
1998年 | 60篇 |
1997年 | 32篇 |
1996年 | 29篇 |
1995年 | 27篇 |
1994年 | 26篇 |
1993年 | 17篇 |
1992年 | 11篇 |
1991年 | 16篇 |
1990年 | 10篇 |
1989年 | 19篇 |
1988年 | 21篇 |
1987年 | 11篇 |
1986年 | 12篇 |
1985年 | 7篇 |
1984年 | 12篇 |
1982年 | 10篇 |
1981年 | 8篇 |
1980年 | 7篇 |
1979年 | 6篇 |
1978年 | 5篇 |
1976年 | 5篇 |
1974年 | 7篇 |
1973年 | 8篇 |
1970年 | 7篇 |
排序方式: 共有8826条查询结果,搜索用时 46 毫秒
141.
Lucas Celia Petersen Luiz Claudio Danzmann Eduardo Bartholomay Luiz Carlos Bodanese Brenda Gonalves Donay Ellen Hettwer Magedanz Adriana Vier Azevedo Gustavo Farias Porciuncula Marcelo Haertel Miglioranza 《Arquivos brasileiros de cardiologia》2021,116(1):14
BackgroundHeart Failure with mid-range Ejection Fraction (HFmEF) was recently described by European and Brazilian guidelines on Heart Failure (HF). The ejection fraction (EF) is an important parameter to guide therapy and prognosis. Studies have shown conflicting results without representative data from developing countries.ObjectiveTo analyze and compare survival rate in patients with HFmEF, HF patients with reduced EF (HFrEF), and HF patients with preserved EF (HFpEF), and to evaluate the clinical characteristics of these patients.MethodsA cohort study that included adult patients with acute HF admitted through the emergency department to a tertiary hospital, reference in cardiology, in south Brazil from 2009 to 2011. The sample was divided into three groups according to EF: reduced, mid-range and preserved. A Kaplan-Meier curve was analyzed according to the EF, and a logistic regression analysis was done. Statistical significance was established as p < 0.05.ResultsA total of 380 patients were analyzed. Most patients had HFpEF (51%), followed by patients with HFrEF (32%) and HFmEF (17%). Patients with HFmEF showed intermediate characteristics related to age, blood pressure and ventricular diameters, and most patients were of ischemic etiology. Median follow-up time was 4.0 years. There was no statistical difference in overall survival or cardiovascular mortality (p=.0031) between the EF groups (reduced EF: 40.5% mortality; mid-range EF 39.7% and preserved EF 26%). Hospital mortality was 7.6%.ConclusionThere was no difference in overall survival rate between the EF groups. Patients with HFmEF showed higher mortality from cardiovascular diseases in comparison with HFpEF patients. (Arq Bras Cardiol. 2021; 116(1):14-23) 相似文献
142.
Nitrogen‐containing bisphosphonate therapy: assessment of the alveolar bone structure in rats – a blind randomized controlled trial
下载免费PDF全文
![点击此处可从《International journal of experimental pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Viviane N. Pacheco Renan Langie Adriana Etges Deise Ponzoni Edela Puricelli 《International journal of experimental pathology》2015,96(4):255-260
This study aimed to assess the effect of zoledronic acid exposure on structures of the alveolar bone of rats. The sample was composed of 42 male Wistar rats. Animals in the T1 and T2 groups received weekly doses of 0.2 mg/kg intraperitoneal zoledronic acid for 3 weeks, while animals in the T3 group received the same treatment for 8 weeks. The control groups C1, C2 and C3 received equivalent doses of saline. The first upper molars of Wistar rats in the C2, T2, C3 and T3 groups were extracted. Cone‐beam computerized tomography scans were performed, and the image density was analysed by grey levels. The presence and type of inflammatory infiltrate, vascularization and bone necrosis were assigned by histological qualitative scores. Histomorphometric analysis of bone density was performed in the groups without extraction. No significant differences were found in the bone grey density estimated by grey‐level value and histomorphometric analysis between the C1 and T1 groups (P > 0.05). The grey levels in the T3 group were lower (P < 0.05) than in the C3 group, corresponding to the bone defect. Histological assessments showed the presence of bone necrosis in the T3 group and lower levels of bone remodelling in the test groups (T2 and T3) compared to the control groups (C2 and C3). The results of qualitative analyses did not differ significantly between the groups (P > 0.05). Zoledronic acid‐exposed animals showed maxillary changes including reduced grey levels, the presence of bone necrosis and a higher prevalence of inflammatory signs. 相似文献
143.
Adriana Olar Khalida M. Wani Erik P. Sulman Alireza Mansouri Gelareh Zadeh Charmaine D. Wilson Franco DeMonte Gregory N. Fuller Kenneth D. Aldape 《Brain pathology (Zurich, Switzerland)》2015,25(3):266-275
While World Health Organization (WHO) grading of meningioma stratifies patients according to recurrence risk overall, there is substantial within‐grade heterogeneity with respect to recurrence‐free survival (RFS). Most meningiomas are graded according to mitotic counts per unit area on hematoxylin and eosin sections, a method potentially confounded by tumor cellularity, as well as potential limitations of accurate mitotic figure detection on routine histology. To refine mitotic figure assessment, we evaluated 363 meningiomas with phospho‐histone H3 (Ser10) and determined the mitotic index (number of mitoses per 1000 tumor cells). The median mitotic indices among WHO grade I (n = 268), grade II (n = 84) and grade III (n = 11) tumors were 1, 4 and 12. Classification and regression tree analysis to categorize cut‐offs identified three subgroups defined by mitotic indices of 0–2, 3–4 and ≥5, which on univariate analysis were associated with RFS (P < 0.01). In multivariate analysis, mitotic index subgrouped in this manner was significantly associated with RFS (P < 0.01) after adjustment for Simpson grade, WHO grade and MIB‐1 index. Mitotic index was then examined within individual WHO grade, showing that for grade I and grade II meningiomas, mitotic index can add additional information to RFS risk. The results suggest that the use of a robust mitotic marker in meningioma could refine risk stratification. 相似文献
144.
Grassi N Cipolla C Torcivia A Mandala S Graceffa G Bottino A Latteri F 《World journal of gastroenterology : WJG》2008,14(8):1302-1304
Gastrointestinal stromal tumour (GIST) is a rare tumour of the gastrointestinal tract which does not generally originate in the rectum. The authors describe a case of a 70-year-old man who underwent an anterior resection of the rectum for a low-risk GIST. The patient was not given adjuvant chemotherapy with imatinib and is still disease-free 30 mo after surgery. The authors conclude that although rectal GIST is extremely uncommon, it should be included in differential diagnosis when a tumour in the rectum is detected. Biopsy of the tumour is essential, since this makes it possible to reach a sure preoperative diagnosis based on the immunohistological features of the CDl17 and CD34. Although complete surgical resection with negative tumour margins is the principal curative procedure for primary and nonmetastatic tumours, further studies are still needed for the determination of the most effective treatment strategy for patients with rectal GIST. 相似文献
145.
Canto CL Sumita LM Machado AF Tateno A Cunha EV Machado CM 《Revista do Instituto de Medicina Tropical de S?o Paulo》2008,50(1):61-63
HHV-6 is the etiological agent of Exanthem subitum which is considered the sixth most frequent disease in infancy. In immuno-compromised hosts, reactivation of latent HHV-6 infection may cause severe acute disease. We developed a Sybr Green Real Time PCR for HHV-6 and compared the results with nested conventional PCR. A 214 pb PCR derived fragment was cloned using pGEM-T easy from Promega system. Subsequently, serial dilutions were made in a pool of negative leucocytes from 10-6 ng/microL (equivalent to 2465.8 molecules/microL) to 10-9 (equivalent to 2.46 molecules/microL). Dilutions of the plasmid were amplified by Sybr Green Real Time PCR, using primers HHV3 (5' TTG TGC GGG TCC GTT CCC ATC ATA 3)'and HHV4 (5' TCG GGA TAG AAA AAC CTA ATC CCT 3') and by conventional nested PCR using primers HHV1 (outer): 5'CAA TGC TTT TCT AGC CGC CTC TTC 3'; HHV2 (outer): 5' ACA TCT ATA ATT TTA GAC GAT CCC 3'; HHV3 (inner) and HHV4 (inner) 3'. The detection threshold was determined by plasmid serial dilutions. Threshold for Sybr Green real time PCR was 24.6 molecules/microL and for the nested PCR was 2.46 molecules/microL. We chose the Real Time PCR for diagnosing and quantifying HHV-6 DNA from samples using the new Sybr Green chemistry due to its sensitivity and lower risk of contamination. 相似文献
146.
Homocysteine triggers mucosal microvascular activation in inflammatory bowel disease 总被引:3,自引:0,他引:3
Danese S Sgambato A Papa A Scaldaferri F Pola R Sans M Lovecchio M Gasbarrini G Cittadini A Gasbarrini A 《The American journal of gastroenterology》2005,100(4):886-895
OBJECTIVES: Increased homocysteine contributes to the pathophysiology of several chronic inflammatory diseases. Whether homocysteine could participate in mucosal inflammation in inflammatory bowel disease (IBD) has not been explored yet. Our aims were to study the levels of plasma and mucosal homocysteine in IBD patients and to assess whether homocysteine can trigger an inflammatory reaction on human intestinal microvascular endothelial cells (HIMECs). METHODS: Homocysteine was measured in the plasma, mucosal biopsy, and lamina propria mononuclear cell (LPMC) supernatants from normal and IBD subjects. HIMEC were cultured in presence of homocysteine, TNF-alpha, or folic acid, alone or in combination. Expression of vascular cell adhesion molecule 1 (VCAM-1) and intercellular cell adhesion molecule 1 was measured by flow cytometry and monocyte chemoattractant protein-1 (MCP-1) production by ELISA. Phosphorylation of p38 and p42/44 was assessed by immunoblot in HIMEC extracts. T-cell- and monocyte-HIMEC adhesion assays were used to evaluate the impact of homocysteine on leukocyte adhesion to intestinal endothelial cells. RESULTS: Patients with IBD displayed significantly higher homocysteine plasma and mucosal levels than control subjects. IBD-derived LPMC released higher homocysteine than control-derived LPMC. Treatment of HIMEC with homocysteine, and synergistically with the combination of TNF-alpha and homocysteine, triggered HIMEC inflammation, resulting in VCAM-1 up-regulation, MCP-1 production, and p38 phosphorylation. These events lead to an increased capacity of HIMEC to adhere T- and monocyte cells and were blocked by folic acid treatment. CONCLUSIONS: Homocysteine is increased in both the mucosa and plasma of patients with Crohn's disease and ulcerative colitis and contributes to the inflammatory state of the mucosal IBD endothelium. Therefore, homocysteine could play a proinflammatory role in IBD, which can be efficiently targeted by folic acid supplementation. 相似文献
147.
Dana P. Turner Adriana D. Lebowitz Ivana Chtay Timothy T. Houle 《Current pain and headache reports》2018,22(9):62
Purpose of Review
This review synthesizes the utility of measuring migraine triggers for the purpose of forecasting future headache attacks. The nature of forecasting models, headache triggers as inputs to such models, and how these trigger exposures can be measured for forecasting are reviewed. A critical evaluation of the existing forecasting models in the context of their potential application for preemptive treatment is considered.Recent Findings
A substantial pool of candidate trigger factors could be considered in the creation of forecasting models. However, because mechanistic information about causal factors that precede a migraine attack is not well understood, and such factors are difficult to measure, empirical models that are based on trigger factors that are merely associated with the onset of headache activity are likely to be the focus of forecasting efforts in the near future. Of such factors, stress has considerable empirical support and has been used to successfully forecast future headache attacks within individuals over time. However, at present, existing models possess only modest levels of discrimination and lack strong resolution in generated predictions.Summary
Current headache forecasting models represent an important first step in accurately predicting future headache activity. However, to utilize these models in a preemptive treatment paradigm where the risk of headache is treated prior to the actual experience of pain, these models must achieve greater precision with good calibration and generate predictions that are clinically actionable by individuals in their real-time home environments.148.
Marina Barreto Alvarenga Adriana Amorim Francisco Sonia Maria Junqueira Vasconcellos de Oliveira Flora Maria Barbosa da Silva Gilcéria Tochika Shimoda Lucas Petri Damiani 《Revista latino-americana de enfermagem》2015,23(1):162-168
OBJECTIVE:
to analyse the Redness, Oedema, Ecchymosis, Discharge, Approximation (REEDA) scale reliability when evaluating perineal healing after a normal delivery with a right mediolateral episiotomy.METHOD:
observational study based on data from a clinical trial conducted with 54 randomly selected women, who had their perineal healing assessed at four time points, from 6 hours to 10 days after delivery, by nurses trained in the use of this scale. The kappa coefficient was used in the reliability analysis of the REEDA scale.RESULTS:
the results indicate good agreement in the evaluation of the discharge item (0.75< Kappa ≥0.88), marginal and good agreement in the first three assessments of oedema (0.16< Kappa ≥0.46), marginal agreement in the evaluation of ecchymosis (0.25< Kappa ≥0.42) and good agreement regarding redness (0.46< Kappa ≥0.66). For the item coaptation, the agreement decreased from excellent in the first assessment to good in the last assessment. In the fourth evaluation, the assessment of all items displayed excellent or good agreement among the evaluators.CONCLUSION:
the difference in the scores among the evaluators when applying the scale indicates that this tool must be improved to allow an accurate assessment of the episiotomy healing process. 相似文献149.
G. Adriana Perez Karen Moomaw Rose Billy A. Caceres Wanda Spurlock Barbara Bowers Barbara Lutz Cynthia Arslanian-Engoren Karin Reuter-Rice Toby Bressler Mona Wicks Diana Taylor Versie Johnson-Mallard Elizabeth Kostas-Polston Teresa Hagan Desiree Bertrand Susan C. Reinhard 《Nursing outlook》2018,66(3):337-340
150.
Trent Peng Adriana Pérez Kelley Pettee Gabriel 《Journal of manipulative and physiological therapeutics》2018,41(4):294-303