全文获取类型
收费全文 | 612篇 |
免费 | 19篇 |
国内免费 | 15篇 |
专业分类
儿科学 | 42篇 |
妇产科学 | 9篇 |
基础医学 | 46篇 |
口腔科学 | 8篇 |
临床医学 | 51篇 |
内科学 | 146篇 |
皮肤病学 | 21篇 |
神经病学 | 39篇 |
特种医学 | 156篇 |
外科学 | 43篇 |
综合类 | 14篇 |
预防医学 | 24篇 |
药学 | 34篇 |
中国医学 | 1篇 |
肿瘤学 | 12篇 |
出版年
2021年 | 12篇 |
2019年 | 6篇 |
2018年 | 7篇 |
2016年 | 11篇 |
2014年 | 8篇 |
2013年 | 20篇 |
2012年 | 28篇 |
2011年 | 19篇 |
2010年 | 12篇 |
2009年 | 13篇 |
2008年 | 8篇 |
2007年 | 23篇 |
2006年 | 9篇 |
2005年 | 13篇 |
2004年 | 7篇 |
2003年 | 8篇 |
2002年 | 9篇 |
2001年 | 12篇 |
2000年 | 8篇 |
1999年 | 12篇 |
1998年 | 13篇 |
1997年 | 23篇 |
1996年 | 27篇 |
1995年 | 18篇 |
1994年 | 18篇 |
1993年 | 13篇 |
1991年 | 5篇 |
1990年 | 13篇 |
1989年 | 30篇 |
1988年 | 22篇 |
1987年 | 28篇 |
1986年 | 25篇 |
1985年 | 23篇 |
1984年 | 20篇 |
1983年 | 9篇 |
1982年 | 7篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1979年 | 11篇 |
1977年 | 7篇 |
1976年 | 6篇 |
1975年 | 8篇 |
1973年 | 4篇 |
1972年 | 7篇 |
1971年 | 4篇 |
1970年 | 5篇 |
1969年 | 5篇 |
1968年 | 5篇 |
1967年 | 5篇 |
1965年 | 5篇 |
排序方式: 共有646条查询结果,搜索用时 12 毫秒
641.
John Xie Yuanhao Zu Ala Alkhatib Thaidan T. Pham Frances Gill Albert Jang Stella Radosta Gerard Chaaya Leann Myers Jerry S. Zifodya Christine M. Bojanowski Nassir F. Marrouche Franck Mauvais-Jarvis Joshua L. Denson 《Diabetes care》2021,44(1):188
OBJECTIVECoronavirus disease 2019 (COVID-19) mortality is high in patients with hypertension, obesity, and diabetes. We examined the association between hypertension, obesity, and diabetes, individually and clustered as metabolic syndrome (MetS), and COVID-19 outcomes in patients hospitalized in New Orleans during the peak of the outbreak.RESEARCH DESIGN AND METHODSData were collected from 287 consecutive patients with COVID-19 hospitalized at two hospitals in New Orleans, LA, from 30 March to 5 April 2020. MetS was identified per World Health Organization criteria.RESULTSAmong 287 patients (mean age 61.5 years; female, 56.8%; non-Hispanic Black, 85.4%), MetS was present in 188 (66%). MetS was significantly associated with mortality (adjusted odds ratio [aOR] 3.42 [95% CI 1.52–7.69]), intensive care unit requirement (ICU) (aOR 4.59 [CI 2.53–8.32]), invasive mechanical ventilation (IMV) (aOR 4.71 [95% CI 2.50–8.87]), and acute respiratory distress syndrome (ARDS) (aOR 4.70 [95% CI 2.25–9.82]) compared with non-MetS. Multivariable analyses of hypertension, obesity, and diabetes individually showed no association with mortality. Obesity was associated with ICU (aOR 2.18 [95% CI 1.25–3.81]), ARDS (aOR 2.44 [95% CI 1.28–4.65]), and IMV (aOR 2.36 [95% CI 1.33–4.21]). Diabetes was associated with ICU (aOR 2.22 [95% CI 1.24–3.98]) and IMV (aOR 2.12 [95% CI 1.16–3.89]). Hypertension was not significantly associated with any outcome. Inflammatory biomarkers associated with MetS, CRP and lactate dehydrogenase (LDH), were associated with mortality (CRP [aOR 3.66] [95% CI 1.22–10.97] and LDH [aOR 3.49] [95% CI 1.78–6.83]).CONCLUSIONSIn predominantly Black patients hospitalized for COVID-19, the clustering of hypertension, obesity, and diabetes as MetS increased the odds of mortality compared with these comorbidities individually. 相似文献
642.
Ferris EJ; Ledor K; ben-Avi DD; Baker ML; Robbins KV; McCowan TC; Sharma B 《Radiology》1985,157(2):319-322
The cardiovascular applications of flexible fiber-optic technology are imminent because of recent advances in miniaturization. In the work described here, angioscopy, or vascular endoscopy, was performed in the cadaveric aorta and in the systemic and pulmonary circulations of the canine model and selected human patients. Subsequent to our development of percutaneous techniques, clinical trials have ranged from lower-extremity venoscopy to aortic-root arterioscopy. Angioscopy could be clinically useful because of relative or absolute contraindications to iodinated contrast material. The ability to see in color and three dimensions may afford some other advantages to angioscopy over conventional angiography. 相似文献
643.
Nanoparticle research is currently an area of intense scientific interest due to a wide variety of potential applications. Human beings have been exposed to airborne nanosized particles throughout their evolutionary stages, and such exposures have increased dramatically over the last century. Nanoparticle can modify the physicochemical properties of the material as well as create the opportunity for increased uptake and interaction with biological tissues through inhalation, ingestion, and injection. This combination of effects can generate adverse biological effects in living cells. Nanoparticles have proved toxic to human once in the blood stream, nanoparticles, spleen, bone marrow and nervous system can be transported around the body and be taken up by organs tissue and cell cultures, resulting in increased oxidative stress, inflammatory cytokine production and cell death. Unlike larger particles, nanoparticles may be taken up by cell mitochondria and the cell nucleus studies demonstrate the potential for nanoparticles to cause DNA mutation and induce major structural damage to mitochondria, even resulting in cell death. Size is therefore a key factor in determining the potential toxicity of a particle. How these nanoparticles behave inside the body is still a major question that needs to be resolved. There is a responsibility to test and optimize these new nanomaterials early during the development process to eliminate or ameliorate identified toxic characteristics. 相似文献
644.
Cross-linking of the beta-glucan receptor on human monocytes results in interleukin-1 receptor antagonist but not interleukin-1 production 总被引:7,自引:0,他引:7
The beta-glucan receptor, found on monocytes and neutrophils, binds glucose polymers derived from fungi. Ligands for the receptor have various immunomodulatory effects, including increased microbicidal killing activity. We have investigated the effect of beta-glucans on the production of interleukin-1 (IL-1) and its naturally occurring inhibitor, the IL-1 receptor antagonist (IL-1Ra). Particulate beta- glucan induced IL-1Ra production from human peripheral blood mononuclear cells (PBMC) but did not stimulate IL-1 beta synthesis or gene expression in these same cells. Monomeric (soluble) beta-glucan did not induce IL-1Ra production. However, when preincubated with PBMC, monomeric beta-glucan significantly (P < .01) reduced particulate beta- glucan induction of IL-1Ra by 40%, suggesting that crosslinking of beta- glucan receptors is required for induction of IL-1Ra. In support of this, monomeric beta-glucan immobilized on plastic surfaces stimulated IL-1Ra production. Vitamin D3, which increases the functional capacity of beta-glucan receptors, increased IL-1Ra production induced by particulate beta-glucan, whereas dexamethasone suppressed IL-1Ra synthesis. Because of their differential effects on cytokine production, beta-glucans may be used to therapeutic advantage in the diseases in which IL-1 is implicated. 相似文献
645.
646.
Autologous bone marrow transplantation in follicular non-Hodgkin's lymphoma before and after histologic transformation 总被引:3,自引:2,他引:3
Schouten HC; Bierman PJ; Vaughan WP; Kessinger A; Vose JM; Weisenburger DD; Armitage JO 《Blood》1989,74(7):2579-2584
Patients with disseminated follicular non-Hodgkin's lymphoma (NHL) are only occasionally cured with standard chemotherapy regimens. Although most of these tumors are initially responsive to chemotherapy, in 40% to 70% of patients the lymphoma will eventually transform to an NHL of higher grade malignancy and a poorer prognosis. We treated 18 patients having an original diagnosis of follicular NHL with high-dose therapy and autologous bone marrow transplantation. The lymphomas of 10 of the patients had already undergone histologic transformation and eight still had a follicular histologic pattern. The former group had been followed for a longer time from the diagnosis of NHL and had been more extensively treated with conventional chemotherapy regimens. All eight patients with follicular NHL at the time of transplantation are alive for 246+ to 1,804+ days and seven of the patients are in complete remission. In contrast, of the 10 patients in histologic transformation only 1 is alive and in CR. This reflects the inability of these patients to tolerate the high-dose chemotherapy and myelosuppression as well as resistance of their lymphoma to this therapy. This difference in survival between the two groups was highly significant (P = .002). We conclude that the outcome of patients with follicular NHL transplanted early before histologic transformation is better than for those who are transplanted later in the course of their illness. Because of the relapsing behavior of follicular NHL, a longer follow-up is necessary to prove any impact on the natural history of the disease. 相似文献