全文获取类型
收费全文 | 4356篇 |
免费 | 215篇 |
国内免费 | 34篇 |
专业分类
耳鼻咽喉 | 117篇 |
儿科学 | 183篇 |
妇产科学 | 209篇 |
基础医学 | 336篇 |
口腔科学 | 149篇 |
临床医学 | 411篇 |
内科学 | 1001篇 |
皮肤病学 | 164篇 |
神经病学 | 276篇 |
特种医学 | 191篇 |
外科学 | 970篇 |
综合类 | 66篇 |
预防医学 | 94篇 |
眼科学 | 116篇 |
药学 | 156篇 |
中国医学 | 10篇 |
肿瘤学 | 156篇 |
出版年
2023年 | 31篇 |
2022年 | 50篇 |
2021年 | 100篇 |
2020年 | 82篇 |
2019年 | 90篇 |
2018年 | 134篇 |
2017年 | 104篇 |
2016年 | 171篇 |
2015年 | 160篇 |
2014年 | 178篇 |
2013年 | 278篇 |
2012年 | 316篇 |
2011年 | 333篇 |
2010年 | 199篇 |
2009年 | 154篇 |
2008年 | 298篇 |
2007年 | 318篇 |
2006年 | 280篇 |
2005年 | 291篇 |
2004年 | 227篇 |
2003年 | 194篇 |
2002年 | 167篇 |
2001年 | 109篇 |
2000年 | 69篇 |
1999年 | 62篇 |
1998年 | 28篇 |
1997年 | 12篇 |
1996年 | 14篇 |
1995年 | 8篇 |
1994年 | 10篇 |
1993年 | 9篇 |
1992年 | 18篇 |
1991年 | 8篇 |
1990年 | 11篇 |
1989年 | 8篇 |
1988年 | 10篇 |
1987年 | 10篇 |
1986年 | 6篇 |
1985年 | 7篇 |
1984年 | 7篇 |
1980年 | 3篇 |
1979年 | 5篇 |
1974年 | 3篇 |
1972年 | 2篇 |
1971年 | 2篇 |
1970年 | 3篇 |
1969年 | 2篇 |
1967年 | 6篇 |
1966年 | 3篇 |
1909年 | 2篇 |
排序方式: 共有4605条查询结果,搜索用时 1 毫秒
1.
Karaosmanoglu Ali Devrim Onur Mehmet Ruhi Salman Mehmet Coskun Usubutun Alp Karcaaltincaba Musturay Ozmen Mustafa Nasuh Akata Deniz 《Abdominal imaging》2019,44(4):1493-1505
Abdominal Radiology - Metastatic involvement of the ovaries is not rare. The most common tumor types metastasizing to the ovaries, from non-gynecological organs, are breast, colorectal, gastric,... 相似文献
2.
3.
Adrenergic signalling between rat taste receptor cells 总被引:2,自引:0,他引:2
Scott Herness† Fang-li Zhao Namik Kaya Shao-gang Lu Tiansheng Shen Xiao-Dong Sun‡ 《The Journal of physiology》2002,543(2):601-614
In taste buds, synaptic transmission is traditionally thought to occur from taste receptor cells to the afferent nerve. This communication reports the novel observation that taste receptor cells respond to adrenergic stimulation. Noradrenaline application inhibited outward potassium currents in a dose-dependent manner. This inhibition was mimicked by the β agonist isoproterenol and blocked by the β antagonist propranolol. The α agonists clonidine and phenylephrine both inhibited the potassium currents and elevated intracellular calcium levels. Inwardly rectifying potassium currents were unaffected by adrenergic stimulation. Experiments using the RT-PCR technique demonstrate that lingual epithelium expresses multiple α (α1a, α1b, α1c, α1d, α2a, α2b, α2c) and β (β1, β2) subtypes of adrenergic receptors, and immunocytochemistry localized noradrenaline to a subset of taste receptor cells. Collectively, these data imply strongly that adrenergic transmission within the taste bud may play a paracrine role in taste physiology. 相似文献
4.
The Arg753GLn polymorphism of the human toll-like receptor 2 gene in tuberculosis disease. 总被引:16,自引:0,他引:16
A C Ogus B Yoldas T Ozdemir A Uguz S Olcen I Keser M Coskun A Cilli O Yegin 《The European respiratory journal》2004,23(2):219-223
Toll-like receptor 2 (TLR2), a member of the Toll-like receptor family, plays an important role in recognition of, and subsequent immune response activation against, mycobacteria. The genetic polymorphism of TLR2 (arginine to glutamine substitution at residue 753 (Arg753Gln)) has been associated with a negative influence on TLR2 function, which may, in turn, determine the innate host response to mycobacteria. The aim of the present study was to investigate the Arg753Gln single nucleotide polymorphism of the TLR2 gene in tuberculosis (TB) patients compared to healthy controls. A retrospective case/control study was carried out. The Arg753Gln polymorphism of the TLR2 gene was studied in 151 TB patients compared to 116 ethnically and age-matched healthy control subjects. The TLR2 polymorphism (adenine (A) allele) was observed in 17.9 and 7.7% of TB patients and controls, respectively. When the ratios of the three genotypes were compared between the two groups, the AA genotype was found to be more significantly associated with TB. Allele frequencies for guanine (G) and A were found to be 0.95 and 0.05 in the control group and 0.86 and 0.14 in the TB patient group, respectively. The risk of developing TB disease was increased 6.04- and 1.60-fold for carriers of the AA and GA genotypes, respectively. In conclusion, the present data suggest that the arginine to glutamine substitution at residue 753 polymorphism of the Toll-like receptor 2 gene influences the risk of developing tuberculosis. 相似文献
5.
6.
OBJECTIVE: The study goal was to evaluate whether quantitative analysis of neck drainage contents is an important parameter of objective and early diagnosis of chylous fistula (CF) in the postoperative period. STUDY DESIGN AND SETTING: We prospectively evaluated 103 consecutive neck dissections during a 2-year period at a tertiary academic referral center. Six of the patients (5.8%) had CF. The data obtained from the patients with CF were matched with normal data obtained from patients without CF. RESULTS: A statistically significant difference was found between total drainage volumes of the patients with and those without CF (P < 0.05). In almost all patients with CF, drainage levels of triglycerides and cholesterol on postoperative day 1 were higher than serum levels. The difference between the drainage levels of triglycerides and cholesterol of the patients with and without CF was highly significant (P < 0.001). CONCLUSIONS: Serum and drainage levels of triglycerides and cholesterol on postoperative day 1 can be used as objective and early predictive parameters of CF. 相似文献
7.
Ozlem Coskun Serap Ucler Leyla Cavdar Levent E Inan 《Journal of clinical neuroscience》2007,14(4):334-339
Discontinuation of medication is the treatment of choice for patients with chronic daily headache (CDH) who overuse their medications. This treatment may be difficult due to increased headache severity observed in patients immediately after withdrawal. We retrospectively evaluated the efficacy of valproic acid therapy in 66 patients with overuse of CDH medication during withdrawal therapy. Patients were all withdrawn from medications and valproic acid started at 250 mg or 500 mg daily. Forty-two (63.6%) patients had decreased headache severity, including 27.3% objective responses in the first week. At the last visit in the 12th week, 50 patients were headache-free and only one patient had persistent headache. Fifteen patients withdrew from therapy due to side effects and lost to follow-up within this timeframe. Thus, low dose valproic acid appears to be safe and effective in the management of withdrawal therapy. 相似文献
8.
9.
Osman Inci Esat Kaya Bulent Alagol Irfan Huseyin Atakan Sabahattin Aydin Hasan Ereselli 《International urology and nephrology》2003,36(1):1-4
Methods: Second primary cancers constitute approximately 9–10% of malignancies diagnosed in the United States. We aimed to show the
risk and incidance of second primary tumor occuring associated to urologic tumors and show the distrubution of tumors in Tracia
region. We retrospectively examined the patients' files with the diagnosis of malignant disease between the years 1985–2000.
Hazard function analysis was performed to estimate the relative risk of secondary malignancy occuring. Age, sex and tumor
number were examined to find out if they affect on mortality rate. Results: A total number of 25 MPMNs were diagnosed. In 52 percent of the cases the second primary neoplasm developed within six months.
The relative risk of development of a second neoplasm is found as increasing 1.111 times per month. The incidence of secondary
malignancy occuring in the patients with one tumor was found as 6.31%. Age (p < 0.001) and tumor number (p < 0.001) are found as statistically effective predictor on mortality rate where the sex is not. Conclusions: In the patients with a primary tumor not only the metastasis must be investigated but also second primary tumors should be
taken in to consideration.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
10.
Objective: To investigate whether pentoxifylline could play a role in attenuation of the hazardous effects of ischemia/reperfusion on corporeal tissue in a rat model of veno-occlusive priapism (VOP).
Materials and methods: Placebo and pentoxifylline were given to eight groups of rats prior to priapism being induced by a vacuum constrictive device for durations of 6 and 12 h, respectively. Half of the groups of rats that underwent the same duration of priapism (ischemic) were subjected to 1 h of detumescence after band removal (reperfusion). One group underwent no manipulation and no drug administration and served as a baseline determination (control). Corporeal homogenates were examined for lipid peroxidation (LP) derived malondialdehyde (MDA) accumulation via thiobarbituric acid assay.
Results: MDA concentration differed significantly between VOP rats and controls (P < 0.001) but did not differ significantly between ischemic-only groups and reperfused groups (P > 0.05). In the pentoxifyllinepretreated groups, although MDA accumulation tended to be slightly lower than in the placebo groups, the difference was not statistically significant (P > 0.05) either in the 6- or 12-h duration priapic groups.
Conclusions: LP, an indicator of radical oxygen metabolite (ROM) induced injury, occurs in rat corporeal tissue during and after abolishment of VOP. Single-dose pentoxifylline pretreatment failed to exert a protective effect on corporeal tissue in a rat model of VOP in terms of attenuation of LP. 相似文献