全文获取类型
收费全文 | 11556篇 |
免费 | 502篇 |
国内免费 | 83篇 |
专业分类
耳鼻咽喉 | 267篇 |
儿科学 | 497篇 |
妇产科学 | 401篇 |
基础医学 | 1034篇 |
口腔科学 | 414篇 |
临床医学 | 960篇 |
内科学 | 2696篇 |
皮肤病学 | 205篇 |
神经病学 | 713篇 |
特种医学 | 514篇 |
外科学 | 2301篇 |
综合类 | 254篇 |
一般理论 | 3篇 |
预防医学 | 465篇 |
眼科学 | 251篇 |
药学 | 634篇 |
中国医学 | 36篇 |
肿瘤学 | 496篇 |
出版年
2024年 | 8篇 |
2023年 | 108篇 |
2022年 | 232篇 |
2021年 | 393篇 |
2020年 | 209篇 |
2019年 | 278篇 |
2018年 | 331篇 |
2017年 | 242篇 |
2016年 | 382篇 |
2015年 | 432篇 |
2014年 | 542篇 |
2013年 | 622篇 |
2012年 | 802篇 |
2011年 | 813篇 |
2010年 | 483篇 |
2009年 | 424篇 |
2008年 | 788篇 |
2007年 | 890篇 |
2006年 | 880篇 |
2005年 | 812篇 |
2004年 | 686篇 |
2003年 | 550篇 |
2002年 | 483篇 |
2001年 | 86篇 |
2000年 | 82篇 |
1999年 | 69篇 |
1998年 | 60篇 |
1997年 | 43篇 |
1996年 | 53篇 |
1995年 | 29篇 |
1994年 | 21篇 |
1993年 | 22篇 |
1992年 | 24篇 |
1991年 | 20篇 |
1990年 | 24篇 |
1989年 | 31篇 |
1988年 | 20篇 |
1987年 | 19篇 |
1986年 | 18篇 |
1985年 | 18篇 |
1984年 | 8篇 |
1983年 | 11篇 |
1982年 | 6篇 |
1980年 | 6篇 |
1979年 | 7篇 |
1978年 | 8篇 |
1974年 | 5篇 |
1973年 | 9篇 |
1972年 | 7篇 |
1971年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Gullu H Caliskan M Erdogan D Yilmaz S Dursun R Ciftci O Topcu S Yucel E Muderrisoglu H 《Annals of medicine》2007,39(2):154-159
BACKGROUND: Behcet's disease (BD) is characterized with remissions and exacerbations. However, to date, there is no study to investigate a possible association of disease activity (active versus inactive disease period) with cardiovascular complications. METHODS: Forty patients with BD were evaluated in both active and in inactive disease period. For the control group 45 healthy volunteers, age and sex matched, were registered. Subjects with at least a 15-day lesion-free period were regarded in inactive disease period, and subjects with any oral, skin, and/or genital lesion was regarded as in active disease period. In each subject coronary diastolic peak flow velocities (DPFV) were measured at baseline and after dipyridamole infusion (0.84 mg/kg over 6 minutes) using an Acuson Sequoia C256 echocardiography system. Coronary flow reserve (CFR) was defined as the ratio of hyperemic to baseline DPFV. RESULTS: CFR values were significantly lower in BD patients compared to the controls (2.57+/-0.50 versus 2.87+/-0.53, P = 0.006). In active disease period, basal DPFV (24.6+/-7.5 versus 27.3+/-6.6, P = 0.019) was significantly higher than in the inactive disease period. In the active disease period hyperemic DPFV (61.7+/-14.9 versus 56.8+/-16.7, P = 0.015) values decreased significantly. Therefore, in the active disease period CFR significantly decreased from 2.57+/-0.50 to 2.09+/-0.46, P<0.001. The only independent predictor of CFR within the active disease period was the disease duration (beta = -0.384, P = 0.012). CONCLUSION: Within the active disease period, coronary microvascular function is more prominently impaired in BD patients. Therefore, BD patients are possibly more vulnerable to cardiovascular manifestations when they are in an active disease period. 相似文献
992.
Unalacak M Aydin M Ermis B Ozeren A Sogut A Demirel F Unluoglu I 《The Tohoku journal of experimental medicine》2004,204(1):63-69
The pathogenesis of monosymptomatic nocturnal enuresis is controversial. Various urodynamic studies showed bladder hyperactivity in enuretic children. But the exact cause is not precisely known. The aim of this study was to understand whether the autonomic nervous system dysfunction is involved in this bladder hyperactivity or not. Heart rate variability measurement is widely used for evaluation of cardiac autonomic activity. We evaluated cardiac autonomic nervous system functions in monosymptomatic nocturnal enuretic children by using 24-hour Holter electrocardiogram. The study group consisted of 32 enuretic children (20 boys and 12 girls) and the control group consisted of 20 healthy children (12 boys and 8 girls). In these two groups, we assessed cardiac autonomic regulation by analysis of heart rate variability, and found a significantly higher parasympathetic activity in enuretic children than controls. We suggest that the parasympathetic nervous system hyperactivity plays a role in nocturnal enuresis by causing vesical hyperactivity in monosymptomatic enuretic children. 相似文献
993.
Eda Suer Suha Sayrac Elif Sarinay Hakan Emre Ozturk Mustafa Turkoz Akitoyo Ichinose Tsuyoshi Nagatake Kamruddin Ahmed 《Journal of infection and chemotherapy》2008,14(4):333-336
S-carboxymethylcysteine (S-CMC) is a mucolytic agent that can prevent respiratory infection by decreasing the attachment of respiratory pathogens to human pharyngeal epithelial cells (HPECs). Streptococcus pneumoniae is a major cause of respiratory infections. A previous study revealed that treatment of S. pneumoniae with S-CMC caused a decrease in the attachment of this bacterium to HPECs. In the present study we found that the effect of S-CMC varied according to hosts and strains. S-CMC treatment altered the surface structure of S. pneumoniae, resulting in a decrease of attachment, without affecting the virulence of the bacteria. 相似文献
994.
Burhan Özalp Ömer Berköz Mustafa Aydınol 《Journal of plastic surgery and hand surgery》2018,52(1):7-13
Objective: The aim of this study was to assess the efficacy of suction-assisted liposuction (SAL) in Simon grade 2b gynecomastia and its effect on sternal notch to nipple areola (SNN) distance.Methods: A retrospective analysis was performed on 21 patients with grade 2b gynecomastia who underwent SAL. Preoperative and postoperative SNN distances of the patients were measured, the results were analysed using a Mann–Whitney U test and a p-value <.05 was accepted as statistically significant. Aesthetic results were evaluated by the surgical team considering five criteria: breast size, breast shape, nipple-areolar complex positioning, scarring, and skin tightness of the breast envelope. A 10-point Likert scale was used to assess patient satisfaction with SAL surgery.Results: All of the patients were followed up for an average period of 17.8 months (range?=?12–28 months). The mean amount of lipoaspirate was 232?mL per breast (range?=?190–310?mL). The mean preoperative SNN distance was 22.3?cm (range?=?20–23.5?cm), whereas postoperative was 21.3?cm (range?=?19.2–22.8?cm); the difference was statistically significant (p?.05). There was one case of nipple areola necrosis, three hypoesthesia, five persistent pains, and four slight buttonhole deformities. The aesthetic result was evaluated as very good by the surgical team, and the overall patient satisfaction rate in terms of breast shape and volume was 92%.Conclusions: It was concluded that SAL provides a good aesthetic outcome in patients with Simon grade 2b gynecomastia and shortens the SNN distance by 1?cm, but further clinical studies are required to support this conclusion. 相似文献
995.
Altin T Akyurek O Vurgun K Beton O Sayin T Kilickap M Karaoguz R Guldal M Erol C 《Pacing and clinical electrophysiology : PACE》2007,30(11):1356-1362
BACKGROUND: Pacemaker and implantable cardioverter defibrillator (ICD) implantation increases cardiac troponin I (cTnI) levels which indicates myocardial injury. During implantation of a cardiac resynchronization therapy (CRT) device, balloon inflation for coronary sinus (CS) venogram, cannulation of CS side branch, and electrode advancement may interfere with CS drainage and, hence, may decrease the washout of toxic metabolites from the heart. Thus, CRT implantation may further increase cTnI levels. In this study, we investigated the effects of CRT implantation on cTnI release. METHODS: We included 10 patients (mean age = 57 +/- 15 years) in whom a successful transvenous CRT system was implanted (CRT group). Twenty patients (mean age = 65 +/- 10 years) who underwent a transvenous pacemaker or ICD implantation were included as the control group. Blood samples for cTnI were drawn at baseline and at six, 12, 18, and 24 hours thereafter. RESULTS: Baseline median cTnI levels were similar in CRT and control groups (0.03 ng/mL vs 0.02 ng/mL, respectively; P = 0.1). Postoperative cTnI levels during 24 hours were significantly higher in the CRT group (P < 0.05) by two-way repeated measures of analysis of variance. Post hoc analysis revealed that cTnI levels were higher at the 6th, 12th, 18th, and 24th hours compared to baseline levels (P < 0.001, P < 0.001, P < 0.01, and P < 0.01, respectively). There was a significant difference in the area under the curves (AUCs) of cTnI measurements (1.79 hr.ng/mL in the CRT group and 0.78 hr.ng/mL in the control group, P < 0.05). CONCLUSION: Postoperative cTnI levels were higher after CRT implantation than simple pacemaker/ICD implantation. This may be due to CS manipulation during CRT implantation. 相似文献
996.
Aksakal E Yapici O Yazici M Yilmaz O Sahin M 《The international journal of cardiovascular imaging》2005,21(2-3):185-188
The coronary slow flow phenomenon is an angiographic finding characterized by delayed distal vessel opacification in the absence of epicardial coronary artery disease. Patients often present with acute coronary syndrome. Histopathologic studies have revealed the existence of fibromuscular hyperplasia and myofibrilar hypertrophy. Apical hypertrophic cardiomyopathy is a benign progressive form of hypertrophic cardiomyopathy, that is rarely observed in western communities. It remains commonly asymptomatic until advanced ages. Syncope, arrhythmia or sudden death may be the first symptom. We report a case of slow coronary arterial flow in a 71-year-old male patient with apical hypertrophic cardiomyopathy who experienced chest pain and sudden cardiac arrest due to ventricular arrhythmia. 相似文献
997.
998.
Evidence for a role of adaptive immune response in the disease pathogenesis of the MPTP mouse model of Parkinson's disease 下载免费PDF全文
Heather L. Martin Matteo Santoro Sarah Mustafa Gernot Riedel John V. Forrester Peter Teismann 《Glia》2016,64(3):386-395
Parkinson's disease (PD) is the second most common neurodegenerative disease and results from the loss of dopaminergic neurons of the nigrostriatal pathway. The pathogenesis of PD is poorly understood, but inflammatory processes have been implicated. Indeed increases in the number of major histocompatibility complex II (MHC II) reactive cells have long been recognised in the brains of PD patients at post‐mortem. However whether cells expressing MHC II play an active role in PD pathogenesis has not been delineated. This was addressed utilising a transgenic mouse null for MHC II and the parkinsonian toxin 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP). In wild‐type mice MHC II levels in the ventral midbrain were upregulated 1–2 days after MPTP treatment and MHC II was localized in both astrocytes and microglia. MHC II null mice showed significant reductions in MPTP‐induced dopaminergic neuron loss and a significantly reduced invasion of astrocytes and microglia in MHC II null mice receiving MPTP compared with controls. In addition, MHC II null mice failed to show increases in interferon‐γ or tumour necrosis factor‐α in the brain after MPTP treatment, as was found in wild‐type mice. However, interleukin‐1β was significantly increased in both wild‐type and MHC II null mice. These data indicate that in addition to microglial cell/myeloid cell activation MHC Class II‐mediated T cell activation is required for the full expression of pathology in this model of PD. GLIA 2016;64:386–395 相似文献
999.
Evaluation of oxidative metabolism and oxidative DNA damage in patients with obsessive–compulsive disorder 下载免费PDF全文
1000.
Halil Can Gemalmaz Kerim Sarıyılmaz Okan Ozkunt Seren Gulsen Gurgen Sena Silay 《Acta orthopaedica et traumatologica turcica》2018,52(6):452-458