全文获取类型
收费全文 | 190989篇 |
免费 | 14279篇 |
国内免费 | 2120篇 |
专业分类
耳鼻咽喉 | 1036篇 |
儿科学 | 3727篇 |
妇产科学 | 4451篇 |
基础医学 | 38760篇 |
口腔科学 | 5602篇 |
临床医学 | 23350篇 |
内科学 | 34744篇 |
皮肤病学 | 2882篇 |
神经病学 | 15972篇 |
特种医学 | 7386篇 |
外国民族医学 | 7篇 |
外科学 | 20639篇 |
综合类 | 5995篇 |
现状与发展 | 30篇 |
一般理论 | 7篇 |
预防医学 | 10275篇 |
眼科学 | 2378篇 |
药学 | 12165篇 |
34篇 | |
中国医学 | 1945篇 |
肿瘤学 | 16003篇 |
出版年
2023年 | 7449篇 |
2022年 | 9882篇 |
2021年 | 11410篇 |
2020年 | 12399篇 |
2019年 | 7734篇 |
2018年 | 7776篇 |
2017年 | 8503篇 |
2016年 | 8686篇 |
2015年 | 9314篇 |
2014年 | 16856篇 |
2013年 | 12963篇 |
2012年 | 9637篇 |
2011年 | 8863篇 |
2010年 | 10862篇 |
2009年 | 10346篇 |
2008年 | 5459篇 |
2007年 | 5403篇 |
2006年 | 4577篇 |
2005年 | 3942篇 |
2004年 | 3407篇 |
2003年 | 3267篇 |
2002年 | 3113篇 |
2001年 | 3163篇 |
2000年 | 2693篇 |
1999年 | 2968篇 |
1998年 | 1937篇 |
1997年 | 1010篇 |
1996年 | 908篇 |
1995年 | 730篇 |
1994年 | 702篇 |
1993年 | 587篇 |
1992年 | 922篇 |
1991年 | 911篇 |
1990年 | 870篇 |
1989年 | 713篇 |
1988年 | 725篇 |
1987年 | 469篇 |
1986年 | 318篇 |
1985年 | 502篇 |
1984年 | 511篇 |
1983年 | 502篇 |
1982年 | 447篇 |
1981年 | 402篇 |
1980年 | 389篇 |
1979年 | 348篇 |
1978年 | 308篇 |
1977年 | 263篇 |
1976年 | 287篇 |
1974年 | 236篇 |
1973年 | 240篇 |
排序方式: 共有10000条查询结果,搜索用时 30 毫秒
1.
2.
《Journal of diabetes and its complications》2022,36(3):108134
AimPhysical activity (PA) is recommended to improve glycemic control in T1D; however, the effect of PA on distal symmetric polyneuropathy (DSPN) and cardiac autonomic function in longstanding T1D is unknown.MethodsData from 75 participants were collected as part of the Canadian Study of Longevity in T1D. Participants completed a physical exam, medical history, extensive complications phenotyping and reported their daily PA from the preceding 12-months. Pearson and Spearman correlations were used to assess PA time and complications variables. Linear regression was used to test associations between PA time, neurological and electrophysiological measures. Univariable regression was used to indicate the change in the given independent variables associated with a 30-min increase in PA per week.ResultsParticipants were 66 ± 8 years old with diabetes duration of 54 [52,58] years, HbA1c was 7.3 ± 0.8, 65(89%) had DSPN. Weekly PA time was 156 ± 132 min, and 35(47%) reported ≧150 min/week. Participants with DSPN reported lower PA time compared to individuals without DSPN (141 ± 124 min/week vs. 258 ± 129 min/week; p = 0.015). PA time was associated with better cooling detection threshold (r = 0.24; p = 0.043), peroneal and sural amplitude (r = 0.36; p = 0.0017, rs = 0.26; p = 0.024) and conduction velocity (rs = 0.28; p = 0.015, r = 0.23; p = 0.050). Linear regression adjusting for age and HbA1c, showed that for each 30-min of PA there was a 0.09mv higher peroneal amplitude (p = 0.032) and 0.048 ms lower peroneal F-wave latency (p = 0.022).ConclusionIn longstanding T1D, PA time is associated with superior large nerve fibre function in the lower limbs and some better measures of small nerve fibre function. 相似文献
3.
Espersen Caroline Modin Daniel Hoffmann Søren Hagemann Christoffer A. Hagemann Rikke A. Olsen Flemming J. Fritz-Hansen Thomas Platz Elke Møgelvang Rasmus Biering-Sørensen Tor 《The international journal of cardiovascular imaging》2022,38(1):131-140
The International Journal of Cardiovascular Imaging - Global longitudinal strain (GLS) has proven to be a powerful prognostic marker in various patient populations, but the prognostic value of... 相似文献
4.
5.
6.
Diabetic macular ischaemia (DMI) is traditionally defined and graded based on the angiographic evidence of an enlarged and irregular foveal avascular zone. However, these anatomical changes are not surrogate markers for visual impairment. We postulate that there are vascular phenotypes of DMI based on the relative perfusion deficits of various retinal capillary plexuses and choriocapillaris. This review highlights several mechanistic pathways, including the role of hypoxia and the complex relation between neurons, glia, and microvasculature. The current animal models are reviewed, with shortcomings noted. Therefore, utilising the advancing technology of optical coherence tomography angiography (OCTA) to identify the reversible DMI phenotypes may be the key to successful therapeutic interventions for DMI. However, there is a need to standardise the nomenclature of OCTA perfusion status. Visual acuity is not an ideal endpoint for DMI clinical trials. New trial endpoints that represent disease progression need to be developed before irreversible vision loss in patients with DMI. Natural history studies are required to determine the course of each vascular and neuronal parameter to define the DMI phenotypes. These DMI phenotypes may also partly explain the development and recurrence of diabetic macular oedema. It is also currently unclear where and how DMI fits into the diabetic retinopathy severity scales, further highlighting the need to better define the progression of diabetic retinopathy and DMI based on both multimodal imaging and visual function. Finally, we discuss a complete set of proposed therapeutic pathways for DMI, including cell-based therapies that may provide restorative potential. 相似文献
7.
《Ticks and Tick》2022,13(1):101869
BackgroundAlpha-gal allergy, also known as red meat allergy or alpha-gal syndrome, can present after bites of certain tick species that contain galactose-alpha-1,3-galactose (alpha-gal) carbohydrate. Following this exposure, patients may develop an allergic reaction after mammalian meat consumption. Some heparin products are derived from porcine intestinal tissue, and it is therefore possible that administering these medications to a patient with an alpha-gal allergy may trigger a reaction.ObjectiveThe purpose of this study was to evaluate the incidence of reactions to porcine heparin products in patients with an alpha-gal allergy.MethodsA retrospective case series was conducted by review of electronic medical record data. Patients included were between the ages of 18 and 89 years, with a documented alpha-gal or red meat allergy and an admission to a hospital in the Sentara Healthcare system. The primary outcome was the incidence of allergic reactions upon exposure to heparin products in patients with a documented alpha-gal allergy.ResultsPatients with a documented alpha-gal allergy received a heparin product in 57 of 158 hospital visits (36.1%). Heparin products were tolerated in 56 of the 57 visits (98.3%). The incidence of an alpha-gal reaction to unfractionated heparin was 2.6% (1/39) while the incidence of an alpha-gal reaction to enoxaparin was 0% (0/22).Conclusion and RelevanceHeparin products were associated with a low incidence of alpha-gal reactions among patients with documented alpha-gal allergy. It is possible that enoxaparin poses less of a risk for reaction in these patients compared to unfractionated heparin. 相似文献
8.
《Current problems in cancer》2022,46(6):100896
Head and neck squamous cell carcinoma (HNSCC) is considered an immunosuppressive malignancy. Cross-talk between cancer cells and immune cells is modulated in part by CC ligand (CCL) chemokines, having a major effect on tumor progression. However, the predictive value and function of CCL family members in HNSCC have not been elucidated. Here, the predictive value of CCL members in cancer prognosis and Immune checkpoint blockade therapy response was investigated. CCL17 and CCL22 were screened as the key CCL chemokines in HNSCC through co-expression analysis. Further, the correlation between CCL17/CCL22 expression and cancer immune infiltration were evaluated based on TIMER and were validated by a set of scRNA-seq data. Moreover, the expression level of CCL17/CCL22 we evaluated to predict the response to Immune checkpoint blockade therapy in a panel of cancer types by using the TIDE database. Results indicated that CCL17/CCL22 had a high co-expression correlation and had a marginally statistical significance with the overall survival in HNSCC patients (P value = 0.057 and 0.055, respectively). Our findings showed high expression of CCL17/CCL22 was positively correlated with CD4+ T cell infiltration levels in HNSCCs and activate mTORC1 signaling pathway in CD4+ T cells. Further analysis from TIDE showed the high expression of CCL17/CCL22 might predict favorable responses to immune checkpoint blockade therapy in HNSCC patients. These findings provide an insight into the predictive roles of CCL17/CCL22 in HNSCC. 相似文献
9.
10.