全文获取类型
收费全文 | 1982篇 |
免费 | 167篇 |
国内免费 | 57篇 |
专业分类
耳鼻咽喉 | 43篇 |
儿科学 | 43篇 |
妇产科学 | 19篇 |
基础医学 | 210篇 |
口腔科学 | 29篇 |
临床医学 | 184篇 |
内科学 | 384篇 |
皮肤病学 | 24篇 |
神经病学 | 115篇 |
特种医学 | 65篇 |
外国民族医学 | 1篇 |
外科学 | 306篇 |
综合类 | 189篇 |
现状与发展 | 3篇 |
预防医学 | 148篇 |
眼科学 | 30篇 |
药学 | 190篇 |
2篇 | |
中国医学 | 63篇 |
肿瘤学 | 158篇 |
出版年
2024年 | 7篇 |
2023年 | 28篇 |
2022年 | 46篇 |
2021年 | 67篇 |
2020年 | 60篇 |
2019年 | 44篇 |
2018年 | 47篇 |
2017年 | 47篇 |
2016年 | 49篇 |
2015年 | 66篇 |
2014年 | 78篇 |
2013年 | 82篇 |
2012年 | 106篇 |
2011年 | 151篇 |
2010年 | 93篇 |
2009年 | 71篇 |
2008年 | 89篇 |
2007年 | 100篇 |
2006年 | 93篇 |
2005年 | 114篇 |
2004年 | 68篇 |
2003年 | 101篇 |
2002年 | 85篇 |
2001年 | 72篇 |
2000年 | 51篇 |
1999年 | 60篇 |
1998年 | 38篇 |
1997年 | 27篇 |
1996年 | 29篇 |
1995年 | 16篇 |
1994年 | 20篇 |
1993年 | 7篇 |
1992年 | 22篇 |
1991年 | 23篇 |
1990年 | 25篇 |
1989年 | 24篇 |
1988年 | 9篇 |
1987年 | 16篇 |
1986年 | 11篇 |
1985年 | 6篇 |
1983年 | 4篇 |
1975年 | 4篇 |
1974年 | 3篇 |
1972年 | 5篇 |
1971年 | 3篇 |
1970年 | 3篇 |
1969年 | 4篇 |
1968年 | 8篇 |
1967年 | 3篇 |
1966年 | 3篇 |
排序方式: 共有2206条查询结果,搜索用时 15 毫秒
81.
目前,骨质疏松症的传统治疗方法主要集中于抑制骨破坏和促进骨形成方面,但此单一的治疗方法很难彻底解决多重因素致病的骨质疏松症。近来,许多文献报道血管形成与骨形成之间存在偶联关系,其中骨骼中新发现的H亚型血管成为骨质疏松治疗的新焦点。根据骨骼血管内皮细胞位置和功能的区别,可分为H亚型血管和L亚型血管,而H亚型血管可促进其周围骨祖细胞的分化与增殖。H亚型血管主要分布于干骺端和骨膜下,表现为血小板-内皮细胞粘附分子抗体(CD31)和内皮粘蛋白抗体(endomucin,EMCN)强阳性;而L亚型血管表现为两种内皮细胞抗体(CD31或EMCN)弱阳性,分布于骨干区。实验表明,H亚型内皮细胞与周围的骨祖细胞数量会随着小鼠的老龄化呈正比例下降,而且小鼠体内缺氧诱导型转录因子1α缺失后会出现H亚型内皮细胞和骨祖细胞数量明显降低,这些均提示H亚型血管与骨形成存在偶联关系。笔者着重对H亚型内皮细与骨形成之间存在的偶联关系及其机制进行综述,探讨H亚型内皮细胞与骨质疏松症的关系,以进一步加深对骨质疏松症发生、发展的认识,为骨质疏松症治疗提供新的思路与方法。 相似文献
82.
本文结果表明,免疫增强剂对受照射小鼠有抗辐射作用。照射8Gy的小鼠,照后30min注入I-RNA、MDP+CP-CWS、BCG-CWS+CP-CWS,它们的30天活存率分别为78.4%、73.3%、53.3%、57.1%和50.0%,而对照组只为5.7%。照射8.5Gy的小鼠注入MDP+CP-CWS、TP+CP-CWS,活存率分别为34.8%和57.1%,对照组只为2.08%。照射9Gy的小鼠注入TP+CP-CWS、TP其活存率分别为52.7%、37.5%,对照组全部死亡。 相似文献
83.
目的探讨骨髓水肿综合征(bone marrow edema syndrome,BMES)与股骨头缺血性坏死(avascular necrosis of femoral head,ANFH)的差异。方法广泛查阅国内外关于ANFH及BMES研究的相关文献,进行回顾及综合分析。结果 BMES与ANFH在病理、发病机制、临床表现、治疗方法及预后等方面存在不同。结论 BMES与ANFH是两种不同性质的疾病,微骨折可能是骨髓水肿出现的原因。 相似文献
84.
F. M. González Valverde F. Mauri Barberá M. Molto Aguado N. Torregrosa A. Hernández Quiles F. Menárguez Pina M. J. Gómez Ramos M. García Real J. A. Barreras Mateos J. L. Vázquez Rojas 《European Surgery》2004,36(4):253-256
Summary BACKGROUND: Endometriosis is a relatively common pathology in women of childbearing age and of low parity but rarely shows
extraperitoneal involvement. The main aim of this paper is to raise the attention of specialists to the necessity of carrying
out penetrating diagnosis of nonspecific extraperitoneal masses occurring in women of reproductive age. METHODS: We performed
a retrospective review of six patients diagnosed with extraperitoneal endometriosis who were treated at the Vega Baja University
Hospital (Spain) during the last 5 years. RESULTS: Surgical treatment had positive results in five patients. The preoperative
diagnosis was correctly made in only two patients. The accurate aetiology of endometriosis remains unknown and diagnosis is
based on clinical and cytopathological findings. CONCLUSIONS: Surgical treatment of extraperitoneal endometriosis is recommended.
However, postoperative follow-up is obligatory and hormonal suppressive therapy may be necessary. Medical treatment with gestagens,
Danazol, or agonists of the gonadotropin-releasing hormone are ineffective in endometriomas which are bigger than 2 cm.
相似文献
85.
86.
87.
Nicola Napoli Ann V Schwartz Anne L Schafer Eric Vittinghoff Peggy M Cawthon Neeta Parimi Eric Orwoll Elsa S Strotmeyer Andrew R Hoffman Elizabeth Barrett‐Connor Dennis M Black for the Osteoporotic Fractures in Men Study Research Group 《Journal of bone and mineral research》2018,33(1):63-69
Type 2 diabetes (T2DM) is associated with a significant increase in risk of nonvertebral fractures, but information on risk of vertebral fractures (VFs) in subjects with T2DM, particularly among men, is lacking. Furthermore, it is not known whether spine bone mineral density (BMD) can predict the risk of VF in T2DM. We sought to examine the effect of diabetes status on prevalent and incident vertebral fracture, and to estimate the effect of lumbar spine BMD (areal and volumetric) as a risk factor for prevalent and incident morphometric vertebral fracture in T2DM (n = 875) and nondiabetic men (n = 4679). We used data from the Osteoporotic Fractures in Men (MrOS) Study, which enrolled men aged ≥65 years. Lumbar spine areal BMD (aBMD) was measured with dual‐energy X‐ray absorptiometry (DXA), and volumetric BMD (vBMD) by quantitative computed tomography (QCT). Prevalence (7.0% versus 7.7%) and incidence (4.4% versus 4.5%) of VFs were not higher in T2DM versus nondiabetic men. The risk of prevalent (OR, 1.05; 95% CI, 0.78 to 1.40) or incident vertebral‐fracture (OR, 1.28; 95% CI, 0.81 to 2.00) was not higher in T2DM versus nondiabetic men in models adjusted for age, clinic site, race, BMI, and aBMD. Higher spine aBMD was associated with lower risk of prevalent VF in T2DM (OR, 0.55; 95% CI, 0.48 to 0.63) and nondiabetic men (OR, 0.66; 95% CI, 0.5 to 0.88) (p for interaction = 0.24) and of incident VF in T2DM (OR, 0.50; 95% CI, 0.41 to 0.60) and nondiabetic men (OR, 0.54; 95% CI, 0.33 to 0.88) (p for interaction = 0.77). Results were similar for vBMD. In conclusion, T2DM was not associated with higher prevalent or incident VF in older men, even after adjustment for BMI and BMD. Higher spine aBMD and vBMD are associated with lower prevalence and incidence of VF in T2DM as well as nondiabetic men. © 2017 American Society for Bone and Mineral Research. 相似文献
88.
Associations of 25‐Hydroxyvitamin D and 1,25‐Dihydroxyvitamin D With Bone Mineral Density,Bone Mineral Density Change,and Incident Nonvertebral Fracture 下载免费PDF全文
Christine M Swanson Priya Srikanth Christine G Lee Steven R Cummings Ivo Jans Jane A Cauley Roger Bouillon Dirk Vanderschueren Eric S Orwoll Carrie M Nielson for the Osteoporotic Fractures in Men MrOS Study Research Group 《Journal of bone and mineral research》2015,30(8):1403-1413
Relationships between 1,25‐dihydroxyvitamin D (1,25(OH)2D) and skeletal outcomes are uncertain. We examined the associations of 1,25(OH)2D with bone mineral density (BMD), BMD change, and incident non‐vertebral fractures in a cohort of older men and compared them with those of 25‐hydroxyvitamin D (25OHD). The study population included 1000 men (aged 74.6 ± 6.2 years) in the Osteoporotic Fractures in Men (MrOS) study, of which 537 men had longitudinal dual‐energy X‐ray absorptiometry (DXA) data (4.5 years of follow‐up). A case‐cohort design and Cox proportional hazards models were used to test the association between vitamin D metabolite levels and incident nonvertebral and hip fractures. Linear regression models were used to estimate the association between vitamin D measures and baseline BMD and BMD change. Interactions between 25OHD and 1,25(OH)2D were tested for each outcome. Over an average follow‐up of 5.1 years, 432 men experienced incident nonvertebral fractures, including 81 hip fractures. Higher 25OHD was associated with higher baseline BMD, slower BMD loss, and lower hip fracture risk. Conversely, men with higher 1,25(OH)2D had lower baseline BMD. 1,25(OH)2D was not associated with BMD loss or nonvertebral fracture. Compared with higher levels of calcitriol, the risk of hip fracture was higher in men with the lowest 1,25(OH)2D levels (8.70 to 51.60 pg/mL) after adjustment for baseline hip BMD (hazard ratio [HR] = 1.99, 95% confidence interval [CI] 1.19–3.33). Adjustment of 1,25(OH)2D data for 25OHD (and vice versa) had little effect on the associations observed but did attenuate the hip fracture association of both vitamin D metabolites. In older men, higher 1,25(OH)2D was associated with lower baseline BMD but was not related to the rate of bone loss or nonvertebral fracture risk. However, with BMD adjustment, a protective association for hip fracture was found with higher 1,25(OH)2D. The associations of 25OHD with skeletal outcomes were generally stronger than those for 1,25(OH)2D. These results do not support the hypothesis that measures of 1,25(OH)2D improve the ability to predict adverse skeletal outcomes when 25OHD measures are available. © 2015 American Society for Bone and Mineral Research. 相似文献
89.
Feng Wei Quan Liu Yujia Zhai Zhiqiang Fu Wensen Liu Jingtao Men Hai Lian Chen Chen Yaojun Shi Xing-Quan Zhu 《Acta tropica》2009,111(3):284-344
Two recombinant plasmids, pVAX/SjFABP and pVAX/mIL-18 containing Schistosoma japonicum 14 kDa fatty acid binding protein (SjFABP) and murine IL-18, were constructed and evaluated for their ability to induce immune responses and to protect against S. japonicum challenge in mice. Mice were intramuscularly immunized twice at three-weekly intervals, and challenged with S. japonicum cercariae at 4 weeks after the last vaccination. All animals vaccinated with pVAX/SjFABP alone or plus pVAX/mIL-18 developed specific anti-SWAP ELISA antibody and T lymphocyte proliferation. Co-injection of pVAX/mIL-18 significantly increased the production of IFN-γ and IL-2 compared with pVAX/SjFABP alone, indicating that IL-18 enhances the Th1-dominant immune response. The challenge experiment showed that co-injection of plasmid encoding IL-18 significantly enhances protective effect against S. japonicum infection, as demonstrated by worm reduction rates and the hepatic egg reduction rates 45 days post-challenge. These results indicated that IL-18 may become a novel vaccine adjuvant for development of vaccines against schistosomiasis. 相似文献
90.
Mehmet Ctrk Cosar Batman Gamze Men Murvet Tuncel Orhan Zleloglu 《Clinical & experimental optometry》2007,90(5):367-370
Purpose: To report a case of Alport’s syndrome and to present electronmicroscopic examination findings of the anterior lens capsule of this patient. Method: A 21‐year‐old man was referred for low visual acuity and retinal pigment epithelial changes in the left eye. The patient and his relatives underwent detailed ophthalmological examination, including electrophysiological testing. The patient also underwent electronmicroscopic examination of the anterior lens capsule. Results: His visual acuity was 6/18 OD and 6/15 OS. Anterior lenticonus and subcapsular opacities were observed in the left eye. Cataract extraction by phacoemulsification with intraocular lens implantation was performed for his poor visual performance. During the capsulorhexis, the remarkably thin and fragile anterior capsule was noted and removed. Ultrastructural analysis of the anterior lens capsule showed a thinner central zone compared with the periphery. Conclusions: The course of Alport’s syndrome can be ameliorated by early diagnosis. Therefore, the ophthalmological examination of a patient with anterior lenticonus must be combined with a detailed medical evaluation. Ultrastructural analysis of the lens capsule can support the diagnosis of Alport’s syndrome. 相似文献