全文获取类型
收费全文 | 28841篇 |
免费 | 1734篇 |
国内免费 | 149篇 |
专业分类
耳鼻咽喉 | 362篇 |
儿科学 | 940篇 |
妇产科学 | 612篇 |
基础医学 | 4089篇 |
口腔科学 | 2056篇 |
临床医学 | 2637篇 |
内科学 | 5658篇 |
皮肤病学 | 716篇 |
神经病学 | 2621篇 |
特种医学 | 1113篇 |
外国民族医学 | 4篇 |
外科学 | 3035篇 |
综合类 | 361篇 |
一般理论 | 21篇 |
预防医学 | 2728篇 |
眼科学 | 465篇 |
药学 | 1844篇 |
5篇 | |
中国医学 | 243篇 |
肿瘤学 | 1214篇 |
出版年
2023年 | 268篇 |
2022年 | 533篇 |
2021年 | 938篇 |
2020年 | 624篇 |
2019年 | 780篇 |
2018年 | 994篇 |
2017年 | 724篇 |
2016年 | 748篇 |
2015年 | 927篇 |
2014年 | 1249篇 |
2013年 | 1478篇 |
2012年 | 2107篇 |
2011年 | 2065篇 |
2010年 | 1211篇 |
2009年 | 1050篇 |
2008年 | 1484篇 |
2007年 | 1585篇 |
2006年 | 1351篇 |
2005年 | 1347篇 |
2004年 | 1299篇 |
2003年 | 1134篇 |
2002年 | 972篇 |
2001年 | 613篇 |
2000年 | 578篇 |
1999年 | 491篇 |
1998年 | 232篇 |
1997年 | 196篇 |
1996年 | 149篇 |
1995年 | 139篇 |
1994年 | 116篇 |
1993年 | 122篇 |
1992年 | 256篇 |
1991年 | 261篇 |
1990年 | 240篇 |
1989年 | 211篇 |
1988年 | 235篇 |
1987年 | 201篇 |
1986年 | 159篇 |
1985年 | 160篇 |
1984年 | 130篇 |
1983年 | 90篇 |
1982年 | 83篇 |
1981年 | 67篇 |
1980年 | 65篇 |
1979年 | 110篇 |
1978年 | 87篇 |
1975年 | 67篇 |
1974年 | 86篇 |
1973年 | 87篇 |
1971年 | 73篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Paleari AG Marra J Rodriguez LS de Souza RF Pero AC Mollo Fde A Compagnoni MA 《Journal of oral rehabilitation》2012,39(8):615-622
The objective of this study is to compare the effects of canine guidance (CG) and bilateral balanced occlusion (BBO) on denture satisfaction and kinesiographic parameters of complete denture wearers, by means of a cross-over trial. Fifty edentulous patients received new maxillary and mandibular complete dentures. After the intra-oral adjustments and adaptation period, 44 participants were enrolled in the trial and randomly received a sequence of occlusal schemes: BBO followed by CG, or CG followed by BBO. Outcomes were assessed after 30 days of each occlusal scheme. Participants answered a denture satisfaction questionnaire and a kinesiograph instrument recorded mandibular physiologic movements and pattern of maxillary denture movement during chewing. Wilcoxon test and paired sample t-test were used to compare satisfaction levels and kinesiographic data for each occlusal scheme, respectively (α=0.05). The results showed no differences between occlusal schemes on participant's satisfaction and in any of the kinesiographic parameters studied, except for the vertical intrusion of the maxillary complete denture during chewing, which was lower with CG. It can be concluded that the occlusal scheme did not influence on satisfaction and kinesiographic parameters evaluated, as long as volume and resilience of residual edentulous ridges of the participants were normal. Clinical Trial Registration Identifier: NC.T01420536. 相似文献
992.
993.
Catunda IS de Medeiros MF Santos LA Melo AR 《International journal of oral and maxillofacial surgery》2012,41(3):344-349
By definition, degloving is skin and subcutaneous tissue detachment, most often affecting the limbs and extremities and occasionally the scalp. Degloving generally stems from high-energy trauma, but can also be intentional, such as in the case of planned surgical access in the anterior region of the mandible in oral-maxillofacial surgery. This paper describes an extreme case of complete traumatic maxillofacial degloving that caused partial avulsion of the soft tissues and maxilla. This is an extremely rare condition that has not previously been described in the literature, as the patient survived despite the risk of imminent death. This case report addresses the decisions made regarding the prevention of necrosis and infection that guided the emergency care and subsequent elective steps. 相似文献
994.
Nícolas de Castro Campos Pinto Mariana de Souza Ferreira Maciel Nathalia dos Santos Rezende Ana Paula do Nascimento Duque Renata de Freitas Mendes Jucélia Barbosa da Silva Monique de Rezende Evangelista Luana Cahon Monteiro Josiane Mello da Silva Juliana de Carvalho da Costa Elita Scio 《The Journal of pharmacy and pharmacology》2020,72(12):1933-1945
995.
Myla Lôbo de Souza Lucas Amadeu Gonzaga da Costa Emerson de Oliveira Silva André Luiz Moreira Domingues de Sousa Widson Michael dos Santos Pedro José Rolim Neto 《Drug development research》2020,81(7):803-814
Considered prevalent in many countries on five continents, especially in low-income regions, leishmaniasis is a neglected tropical disease classified by World Health Organization as one of the diseases for which the development of new treatments is a priority. It is an infectious disease caused by protozoa of the genus Leishmania, whose species may cause different clinical manifestations, such as cutaneous and visceral leishmaniasis (VL). Treatment is exclusively by drug therapy, as it has not been possible to develop vaccines yet. Currently available drugs are not fully effective in all cases; they have parenteral administration and exhibit a number of serious and very common adverse effects. The only oral drug available is expensive and it is not available in many endemic countries. Injectable administration is the main problem of treatments, since it requires patients to go to health centers, hospitalization and professional administration, which are conditions that are not adapted to the reality of the poverty conditions of patients with the disease. In this context, the development of an oral medicine has become a focus as it may solve many of these issues. Based on this scenario, this review aimed to investigate which therapeutic alternatives have been studied for the development of oral drugs directed to the treatment of human VL. 相似文献
996.
Thaís Pasqualli Pamella Eduardha E Chaves Lavínia da Veiga Pereira Élvio Adílio Serpa Luís Flávio Souza de Oliveira Michel Mansur Machado 《Clinical and experimental pharmacology & physiology》2020,47(10):1751-1757
One of the most widely used sweeteners in the world is sucralose. With sweetening power 600 times greater than sucrose, its use grows among those who seek to cut calories. Research shows that when heated, sucralose generates toxic products that attack the organism and interact with DNA. Our objective was to test this sweetener under unheated conditions and at average concentrations of consumption, evaluating parameters of cytotoxicity, genotoxicity, and immunotoxicity. For this purpose, we made use of lymphocyte cultures and the analysis of their CD3+, CD4+, and CD8+ subpopulations. In a complementary way, the mechanism of action is proposed here by computational methods. Our results showed that sucralose reduces non-selectively the total lymphocytes due to falls in the levels of the CD4+, CD8+, and CD4+CD8+ subpopulations. We observed an increase in the level of DNA damage and a gradual incidence of structural changes in the lymphocyte chromosomal sets. It was possible to propose that sucralose modulates the gene expression, interfering especially with the MAPK8, APTX, and EID1 genes. This article presents the results of an evidence-based approach to the safety of human health in the use of sucralose. Finally, this study points out that sucralose has cytotoxic, genotoxic, and mutagenic effects in the concentrations and conditions tested in human lymphocyte cell culture. 相似文献
997.
Emma ODonnell Jennifer L. Scheid Sarah L. West Mary Jane De Souza 《Scandinavian journal of medicine & science in sports》2019,29(4):544-553
In estrogen‐deficient post‐menopausal women, osteoporosis shares a common link with cardiovascular disease risk, including endothelial dysfunction. The current study sought to examine associations between bone mineral density (BMD) and endothelial function in estrogen‐deficient premenopausal women with exercise‐associated menstrual disturbances. Recreationally trained women (24.3 ± 0.8 years; overall mean ± SEM) who were estrogen deficient (amenorrheic or eumenorrheic anovulatory cycles; E2Def; n = 13) or estrogen replete (eumenorrheic ovulatory cycles; E2Rep; n = 14) were studied. Total body and lumbar BMD (L1‐L4) were determined using dual‐energy X‐ray absorptiometry. Serum markers of oxidative stress (oxidized low‐density lipoprotein; OxLDL), energy deficiency (triiodothyronine), and bone turnover (osteocalcin, c‐telopeptide X, P1NP) were assessed. Estrogen exposure was determined by assessing daily urinary estrone‐3‐glucuronide (E1G) across a monitoring period. Calf blood flow (CBF), an index of endothelial function, was measured using strain‐gauge plethysmography. CBF, total body and L1‐L4 BMD, triiodothyronine and E1G were lower (P < 0.05), and c‐telopeptide crosslinks higher (P < 0.05) in E2Def. Osteocalcin and OxLDL did not differ (P > 0.05) between groups. L1‐L4 BMD, osteocalcin, and E1G were the strongest predictors of CBF (R2=0.615, P < 0.001). CBF was the strongest predictor of L1‐L4 BMD (R2=0.478, P < 0.001). L1‐L4 (r = 0.558, P = 0.008) and CBF (r = 0.534, P = 0.004) were independently correlated with E1G. In young recreationally trained premenopausal women with anovulatory menstrual disturbances, low CBF predicts decreased lumbar BMD, suggesting impaired peripheral endothelial function may predict early unfavorable changes in bone metabolism. This finding may be of relevance in the early detection of cardiovascular and bone health decrements in otherwise healthy estrogen‐deficient premenopausal women. 相似文献
998.
Lachlan Bird Arkiev DSouza Iain Ball Caroline Rae Robert D. Herbert Bart Bolsterlee 《Scandinavian journal of medicine & science in sports》2019,29(6):808-815
Muscle performance is closely related to the structure and function of tendons and aponeuroses, the sheet‐like, intramuscular parts of tendons. The architecture of aponeuroses has been difficult to study with magnetic resonance imaging (MRI) because these thin, collagen‐rich connective tissues have very short transverse relaxation (T2) times and therefore provide a weak signal with conventional MRI sequences. Here, we validated measurements of aponeurosis dimensions from two MRI sequences commonly used in muscle‐tendon research (mDixon and T1‐weighted images), and an ultrashort echo time (UTE) sequence designed for imaging tissues with short T2 times. MRI‐based measurements of aponeurosis width, length, and area of 20 sheep leg muscles were compared to direct measurements made with three‐dimensional (3D) quantitative microdissection. The errors in measurement of aponeurosis width relative to the mean width were 1.8% for UTE, 3.7% for T1, and 18.8% for mDixon. For aponeurosis length, the errors were 7.6% for UTE, 1.9% for T1, and 21.0% for mDixon. Measurements from T1 and UTE scans were unbiased, but mDixon scans systematically underestimated widths, lengths, and areas of the aponeuroses. Using the same methods, we then found high inter‐rater reliability (intraclass correlation coefficients >0.92 for all measures) of measurements of the dimensions of the central aponeurosis of the human tibialis anterior muscle from T1‐weighted scans. We conclude that valid and reliable measurements of aponeurosis dimensions can be obtained from UTE and from T1‐weighted scans. When the goal is to study the macroscopic architecture of aponeuroses, UTE does not hold an advantage over T1‐weighted imaging. 相似文献
999.
1000.
Neuroprotective Effects of Sulphated Agaran from Marine Alga Gracilaria cornea in Rat 6‐Hydroxydopamine Parkinson's Disease Model: Behavioural,Neurochemical and Transcriptional Alterations
下载免费PDF全文
![点击此处可从《Basic & clinical pharmacology & toxicology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Ricardo Basto Souza Annyta Fernandes Frota Rayane Siqueira Sousa Nayara Araújo Cezario Tarcizio Brito Santos Luziana Mara Frota Souza Chistiane Oliveira Coura Valdécio Silvano Monteiro Gerardo Cristino Filho Silvânia Maria Mendes Vasconcelos Rodrigo Maranguape Silva da Cunha Lissiana Magna Vasconcelos Aguiar Norma Maria Barros Benevides 《Basic & clinical pharmacology & toxicology》2017,120(2):159-170