全文获取类型
收费全文 | 873篇 |
免费 | 59篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 14篇 |
妇产科学 | 21篇 |
基础医学 | 83篇 |
口腔科学 | 25篇 |
临床医学 | 98篇 |
内科学 | 188篇 |
皮肤病学 | 14篇 |
神经病学 | 30篇 |
特种医学 | 11篇 |
外科学 | 115篇 |
综合类 | 19篇 |
预防医学 | 114篇 |
眼科学 | 14篇 |
药学 | 144篇 |
中国医学 | 14篇 |
肿瘤学 | 29篇 |
出版年
2024年 | 2篇 |
2023年 | 14篇 |
2022年 | 20篇 |
2021年 | 46篇 |
2020年 | 30篇 |
2019年 | 41篇 |
2018年 | 48篇 |
2017年 | 27篇 |
2016年 | 42篇 |
2015年 | 27篇 |
2014年 | 41篇 |
2013年 | 41篇 |
2012年 | 79篇 |
2011年 | 80篇 |
2010年 | 40篇 |
2009年 | 45篇 |
2008年 | 53篇 |
2007年 | 39篇 |
2006年 | 37篇 |
2005年 | 38篇 |
2004年 | 29篇 |
2003年 | 33篇 |
2002年 | 26篇 |
2001年 | 13篇 |
2000年 | 5篇 |
1999年 | 5篇 |
1998年 | 6篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 4篇 |
1994年 | 1篇 |
1992年 | 3篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1974年 | 2篇 |
1973年 | 1篇 |
排序方式: 共有935条查询结果,搜索用时 15 毫秒
151.
Muhammad Adil Soofi Muhammad Azam Shah Ammar Mohammed AlQadhi Abdullah Mofareh AlAnazi Waleed M. Alshehri Amir Umair 《Journal of the Saudi Heart Association》2021,33(3):228
ObjectiveEchocardiography is helpful in assessment of pulmonary hemodynamic, however its correlation with Right heart catheterization (RHC) is conflicting. We conducted a study to evaluate sensitivity and specificity of pulmonary hemodynamic parameters measured in echocardiography. Furthermore its correlation with the values measured in RHC was assessed.MethodRetrospective, cross-sectional study conducted at King Fahad medical City, Riyadh, Saudi Arabia. 95 adult patients referred for right heart catheterization were enrolled in the study. All the patients had echocardiography and RHC within one week of each other.ResultDiabetes mellitus, hypertension and dyslipidemia were present among 55%, 66% and 41% of patients respectively. 85% of the study participants were diagnosed to have pulmonary hypertension and 79% of the study participants had postcapillary pulmonary hypertension. Sensitivity of pulmonary artery systolic pressure (PAPs), mean pulmonary artery pressure (PAPm) using PAPs and pulmonary artery acceleration velocity (PAcT) were 86%, 93% and 89% respectively. Correlation of PAPs, PAPm using PAPs and PAcT on echo with invasive hemodynamic in RHC were 0.56, 0.43 and 0.24 respectively. Among patients with moderate to severe Tricuspid Regurgitation (TR) and tricuspid annular plane systolic excursion (TAPSE) <1.5cm correlation of PAPs, PAPm using PAPs and PAcT on echocardiography with right heart catheterization were 0.31, 0.24 and 0.42 respectively.ConclusionEchocardiographic assessment of PAPs and PAPm has high sensitivity and weak to moderate correlation with hemodynamic data in RHC. PAPs measurement on echocardiogram has best correlation with invasive measurement followed by PAPm measurement using PAPs. Among patients with moderate to severe TR and TAPSE <1.5cm PAPm measurement using PAcT has better correlation than using PAPs. 相似文献
152.
Echinacea plants as antioxidant and antibacterial agents: From traditional medicine to biotechnological applications
下载免费PDF全文
![点击此处可从《Phytotherapy research : PTR》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Mehdi Sharifi‐Rad Dima Mnayer Maria Flaviana Bezerra Morais‐Braga Joara Nályda Pereira Carneiro Camila Fonseca Bezerra Henrique Douglas Melo Coutinho Bahare Salehi Miquel Martorell María del Mar Contreras Azam Soltani‐Nejad Yoshie Adriana Hata Uribe Zubaida Yousaf Marcello Iriti Javad Sharifi‐Rad 《Phytotherapy research : PTR》2018,32(9):1653-1663
The genus Echinacea consists of 11 taxa of herbaceous and perennial flowering plants. In particular, Echinacea purpurea (L.) Moench is widely cultivated all over the United States, Canada, and in Europe, exclusively in Germany, for its beauty and reported medicinal properties. Echinacea extracts have been used traditionally as wound healing to improve the immune system and to treat respiratory symptoms caused by bacterial infections. Echinacea extracts have demonstrated antioxidant and antimicrobial activities, and to be safe. This survey aims at reviewing the medicinal properties of Echinacea species, their cultivation, chemical composition, and the potential uses of these plants as antioxidant and antibacterial agents in foods and in a clinical context. Moreover, the factors affecting the chemical composition of Echinacea spp. are also covered. 相似文献
153.
Herbal medicine as a promising therapeutic approach for the management of vascular dementia: A systematic literature review
下载免费PDF全文
![点击此处可从《Phytotherapy research : PTR》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Adel Ghorani‐Azam Samaneh Sepahi Elham Khodaverdi Seyed Ahmad Mohajeri 《Phytotherapy research : PTR》2018,32(9):1720-1728
Vascular dementia (VaD) generally refers to memory deficits and cognitive abnormalities that are resulted from vascular disease. In this study, we aimed to systematically review the literature wherein therapeutic effects of medicinal plants have been studied on VaD. A systematic literature search was performed in the PubMed, Scopus, Web of Science, Google Scholar, and other databases using VaD, and medicinal plants as key terms. No strict inclusion criteria were defined, and almost all clinical studies were included. A total of 524 articles were found, of which only 28 relevant articles with 3461 studied patients were included to this systematic review. The results showed that medicinal plants, particularly Sancaijiangtang and Ginkgo biloba could improve behavioral and psychological symptoms, working memory, Mini‐Mental State Examination, and activities of daily living as well as neuropsychiatric features. It was also shown that the age, average progression of the disease, and the type of folk medicines effective in treating the disease are important factors in the management of VaD. The results of this review indicated that herbal therapy can be a potential candidate in the treatment of VaD; however, further studies are needed to confirm such efficiency. 相似文献
154.
Marcello Iriti Miquel Martorell William N. Setzer María del Mar Contreras Bahare Salehi Azam Soltani‐Nejad Sadegh Rajabi Mercedeh Tajbakhsh Javad Sharifi‐Rad 《Phytotherapy research : PTR》2018,32(9):1675-1687
Carvacrol (CV) is a phenolic monoterpenoid found in essential oils of oregano (Origanum vulgare), thyme (Thymus vulgaris), pepperwort (Lepidium flavum), wild bergamot (Citrus aurantium bergamia), and other plants. Carvacrol possesses a wide range of bioactivities putatively useful for clinical applications such antimicrobial, antioxidant, and anticancer activities. Carvacrol antimicrobial activity is higher than that of other volatile compounds present in essential oils due to the presence of the free hydroxyl group, hydrophobicity, and the phenol moiety. The present review illustrates the state‐of‐the‐art studies on the antimicrobial, antioxidant, and anticancer properties of CV. It is particularly effective against food‐borne pathogens, including Escherichia coli, Salmonella, and Bacillus cereus. Carvacrol has high antioxidant activity and has been successfully used, mainly associated with thymol, as dietary phytoadditive to improve animal antioxidant status. The anticancer properties of CV have been reported in preclinical models of breast, liver, and lung carcinomas, acting on proapoptotic processes. Besides the interesting properties of CV and the toxicological profile becoming definite, to date, human trials on CV are still lacking, and this largely impedes any conclusions of clinical relevance. 相似文献
155.
Syeda Hafiza Benish Ali Kashif Sardar Bangash Abdur Rauf Muhammad Younis Khursheed Anwar Raja Khurram Muhammad Athar Khawaja Maleeha Azam Abid Ali Qureshi Saeed Akhter Lambertus A. Kiemeney Raheel Qamar 《Familial cancer》2017,16(4):577-594
Urothelial bladder carcinoma (UBC) is the most common among urinary bladder neoplasms. We carried out a preliminary study to determine the genetic etiology of UBC in Pakistani population, for this 25 sequence variants from 17 candidate genes were studied in 400 individuals by using polymerase chain reaction-based techniques. Multivariate logistic regression analysis was performed for association analysis of the overall data as well as the data stratified by smoking status, tumor grade and tumor stage. Variants of GSTM1, IGFBP3, LEPR and ACE were found to be associated with altered UBC risk in the overall comparison. CYP1B1 and CDKN1A variants displayed a risk modulation among smokers; IGFBP3 and LEPR variants among nonsmokers while GSTM1 polymorphism exhibited association with both. GSTM1 and LEPR variants conferred an altered susceptibility to low grade UBC; GSTT1, IGFBP3 and PPARG variants to high grade UBC while ACE polymorphism to both grades. GSTM1 and LEPR variants exhibited risk modulation for non-muscle-invasive bladder cancer (NMIBC); GSTT1 and PPARG variants for muscle-invasive bladder cancer (MIBC), and ACE variant for NMIBC as well as MIBC. In general, the susceptibility markers were common for low grade and NMIBC; and distinct from those for high grade and MIBC indicating the distinct pathologies of both groups. In brief, our results conform to reports of previously associated variants in addition to identifying novel potential genetic predictors of UBC susceptibility. 相似文献
156.
157.
Impact of antioxidant supplementations on cardio‐renal protection in cardiac surgery: an updated and comprehensive meta‐analysis and systematic review
下载免费PDF全文
![点击此处可从《Cardiovascular therapeutics》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Sadegh Ali‐Hassan‐Sayegh Seyed Jalil Mirhosseini Mahbube Tahernejad Parisa Mahdavi Azadeh Shahidzadeh Ali Akbar Karimi‐Bondarabadi Ali‐Mohammad Dehghan Elham Rahimizadeh Fatemeh Haddad Zahra Ghodratipour Zahra Sarrafan‐Chaharsoughi Arezoo Shahidzadeh Azam Ghanei Mohammadreza Lotfaliani Mohamed Zeriouh Alexander Weymann Aron‐Frederik Popov Anton Sabashnikov 《Cardiovascular therapeutics》2016,34(5):360-370
This systematic review with meta‐analysis sought to determine the strength of evidence in terms of the impact of common antioxidant supplementations, such as N‐acetylcysteine (NAC), vitamin C, and polyunsaturated fatty acids (PUFA) on perioperative outcomes after cardiac surgery with particular focus on the incidence of atrial fibrillation (AF) and acute kidney injury (AKI) with associated mortality. A total of 29 trials were identified that reported incidence of AF and 17 trials that reported incidence of AKI. Pooled analysis reported that NAC (OR=0.5; P=.001), vitamin C (OR=0.4; P=.001), and PUFA (OR=0.8; P=.01) administration were associated with significantly reduced incidence of AF. In terms of postoperative AKI, only NAC was shown to be a beneficial supplement that was able to significantly reduce the incidence of AKI (OR=0.7; P=.01), and NAC could also significantly decrease overall mortality (OR=0.3; P=.03) following cardiac surgery. The use of NAC in patients undergoing cardiac surgery should be strongly recommended due to its combined cardio‐renal protective effects and reduced mortality. Also, PUFA and vitamin C might be able to significantly decrease the incidence of arrhythmia; however, reno‐protective effects and impact on overall mortality of these supplements seem to be less impressive. 相似文献
158.
Alireza Kordafshari Azam Amirian Sirous Zeinali Atefeh Valaei Fereshteh Maryami 《Hemoglobin》2016,40(1):44-47
δ-Thalassemia (δ-thal) (OMIM #142000) resulting from mutations on the HBD gene usually has no clinical consequences. However, it may cause the misdiagnosis of β-thalassemia (β-thal) carriers by lowering the Hb A2 level to the normal range. Therefore, a study for δ-thal should be considered as a step in the detection of at-risk couple in our region. The aim of the present study was to characterize the mutations of the HBD gene in β-thal carriers with normal Hb A2 levels, and also in normal individuals with Hb A2 of less than 2.0%. Four β-thal carriers with normal Hb A2 and 39 individuals with Hb A2 of less than 2.0% were enrolled. Genomic DNA was extracted by the salting out method and the HBD gene was investigated by polymerase chain reaction (PCR) and direct DNA sequencing. Hb A2-Yialousa (HBD: c.82?G?>?T) was the most common variant found in the HBD gene, but the following mutations were also found: Hb A2-NYU (HBD: c.39?T?>?A), Hb A2-Coburg (HBD: c.350?G?>?A), Hb A2-Etolia (HBD: c.257?T?>?C), Hb A2-Fitzroy (HBD: c.428?C?>?A) and the δ-IVS-I-5 (G?>?T) (HBD: c.92?+?5?G?>?T). One case was a compound heterozygote for δ-IVS-I-5/Hb A2-Fitzroy. The results of this single center study suggest that the mutations in the HBD gene in the Iranian population are heterogeneous and should be considered in genetic counseling of families. 相似文献
159.
Biochemical,histopathological, and transmission electron microscopic ultrastructural changes in mice after exposure to silver nanoparticles
下载免费PDF全文
![点击此处可从《Environmental toxicology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Mohammad Azam Ansari Haris M. Khan Aijaz A. Khan Mohammad A. Alzohairy Mohammad Waseem Mohammad Kaleem Ahmad Abbas Ali Mahdi 《Environmental toxicology》2016,31(8):945-956
Four‐week‐old mice, weighing about 25–35 g were divided into five groups (8 mice in each group): vehicle control, low‐ (0.5 g/kg), middle‐ (1 g/kg), high‐ (3 g/kg), and exceptionally high‐dose (5 g/kg). After first and second weeks of intraperitoneal exposure to AgNPs, biochemical, histopathological, and electron microscopic ultrastructural changes were investigated. No significant changes were observed in SGOT and ALP levels after first week of exposure, while the level of SGPT significantly increased (p < 0.05) in 2nd week treated mice, indicating that inflammatory of liver might be induced by high‐dose (3 and 5 g/kg) of AgNPs. No obvious changes were observed for UA and BUN in all groups of treated mice. However, significant (p < 0.05) decrease in CR level was noticed in all groups of treated mice only at high‐dose (3 and 5 g/kg). No remarkable changes in lipid profile were observed. Light microscopic histopathological investigation shows that first week treatment had not perceptible effect on the cytoarchitecture on liver, kidney, and spleen; while, second week treatment had only sporadic mild effects on these organs. However, no ultrastructural electron microscopic changes were observed in liver, kidney, and spleen of mice treated with 0.5, 1, and 3 g/kg of AgNPs when sacrificed on first and second week; while, exceptionally high‐dose (5 g/kg) of AgNPs resulted in slight nuclear chromatin condensation and irregularities in nuclear membrane. The results suggested that AgNPs could be well tolerated in mice when given intraperitoneally and no death has been found during the experiment in any groups of treated mice. Interestingly, significant (<0.05) decrease in glucose levels in all experiment group is suggestive of curious hypoglycemic role of AgNPs warranting further study to explore its possible therapeutic potential in hyperglycemic conditions as well as its mechanism of action at molecular level. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 945–956, 2016. 相似文献
160.