全文获取类型
收费全文 | 22078篇 |
免费 | 2121篇 |
国内免费 | 1283篇 |
专业分类
耳鼻咽喉 | 198篇 |
儿科学 | 277篇 |
妇产科学 | 416篇 |
基础医学 | 2011篇 |
口腔科学 | 433篇 |
临床医学 | 2943篇 |
内科学 | 2918篇 |
皮肤病学 | 253篇 |
神经病学 | 974篇 |
特种医学 | 677篇 |
外国民族医学 | 8篇 |
外科学 | 1445篇 |
综合类 | 4469篇 |
现状与发展 | 10篇 |
一般理论 | 1篇 |
预防医学 | 2046篇 |
眼科学 | 556篇 |
药学 | 2767篇 |
17篇 | |
中国医学 | 1732篇 |
肿瘤学 | 1331篇 |
出版年
2024年 | 74篇 |
2023年 | 321篇 |
2022年 | 798篇 |
2021年 | 1025篇 |
2020年 | 826篇 |
2019年 | 609篇 |
2018年 | 636篇 |
2017年 | 689篇 |
2016年 | 619篇 |
2015年 | 970篇 |
2014年 | 1229篇 |
2013年 | 1278篇 |
2012年 | 1832篇 |
2011年 | 1918篇 |
2010年 | 1467篇 |
2009年 | 1241篇 |
2008年 | 1474篇 |
2007年 | 1362篇 |
2006年 | 1313篇 |
2005年 | 1110篇 |
2004年 | 803篇 |
2003年 | 715篇 |
2002年 | 662篇 |
2001年 | 496篇 |
2000年 | 409篇 |
1999年 | 311篇 |
1998年 | 179篇 |
1997年 | 186篇 |
1996年 | 138篇 |
1995年 | 139篇 |
1994年 | 101篇 |
1993年 | 67篇 |
1992年 | 89篇 |
1991年 | 78篇 |
1990年 | 62篇 |
1989年 | 53篇 |
1988年 | 47篇 |
1987年 | 35篇 |
1986年 | 35篇 |
1985年 | 17篇 |
1984年 | 11篇 |
1983年 | 7篇 |
1982年 | 7篇 |
1981年 | 7篇 |
1977年 | 5篇 |
1976年 | 3篇 |
1975年 | 3篇 |
1974年 | 3篇 |
1973年 | 4篇 |
1972年 | 4篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
Purpose: To investigate the relationships between the axonal sprouting and target neurotization by central neurons after nerve heterocon-nection. Methods: Unilateral (right) vagal-hypoglossal nerve anastomosis (VHA) was performed in adult cats. Following 3-315 days postoperation (dpo), quantitative analyses and ultrastructural changes in the proximal portion of the vagal-hypoglossal heteroconnected nerve as well as the time course of neuronal regeneration were studied. Along with this, horseradish peroxidase (HRP) retrograde tracing technique was used to label the neurons of dorsal motor vagal nucleus (DMV) and nucleus ambiguus (NA) to ascertain if target neurotization was established. Results: The contralateral (left) intact vagus nerve proximal to the level of ansa cervicalis showed an average of 33 +/- 1 myelinated and 74 +/- 4 unmyelinated axons in 727 &mgr;m(2) sectional area of the nerve. In the heteroconnected nerve at the corresponding level just proximal to the anastomosis site, there was a marked increase in the number of small axons sprouting from the unmyelinated nerve fibers between 18 and 25 dpo. The number of these axonal sprouts appeared to decline at 32 dpo but its increase of 131 % was sustained until the late regeneration stage at 315 dpo when compared with the contralateral nerve serving as a control. The mean number of myelinated axons per area unit (727 &mgr;m(2)) was reduced to 18 at 3 dpo but was immediately restored to the normal range at 7 dpo. The retrograde labelling of neurons in both the DMV and NA was first detected at 22 dpo and was progressively increased peaking by about 67 dpo. Conclusions: We conclude that compared with the unmyelinated axons, the myelinated axons may acquire a superior interaction with the new target. Furthermore, the postoperative neurotization of tongue muscles may initiate and facilitate the retraction of the redundant axonal sprouts. 相似文献
32.
逍遥散由当归、白芍、白术、茯苓、炙甘草、柴胡、生姜、薄荷组成,有疏肝解郁,健脾和营之功[1].后世医家在原方基础上加减化裁,广泛应用于临床各科.凡邪在半表半里者,出现肝郁脾虚之证,均可采用,以调其偏胜,扶其不足,使病去人安.笔者临床应用逍遥散治疗肝郁不舒、克伐脾土、脾失健运、气血失和而产生的各种皮肤疾患,收到较好的疗效. 相似文献
33.
34.
目的 研究金属烤瓷修复体制作过程中经常出现的问题及如何补救,探讨提高金瓷修复体修复工艺方面的问题。方法 收集并分析临床近5年制作的580例、共650件金属烤瓷修复体,归纳其在制作中出现的问题。结果 瓷裂及崩瓷18件,占2.76%:气泡15件,占2.31%;铸造缺陷11件,占1.69%;色泽不协调12件,占1.85%。结论 金瓷修复体的加工制作是一个复杂而细致的过程,与技工室制作、临床设计及牙体制备都有密切关系,其中任何一个环节的操作不当都可能导致修复体的失败。 相似文献
35.
Background:The findings on the effectiveness of platelet-rich plasma, ozone, and hyaluronic acid in the treatment of osteoarthritis of the knee are controversial, and the existing original studies and meta-analyses are mostly comparisons of a single joint cavity injection method, lacking direct and indirect comparisons of different drugs in the joint cavity. The lack of direct and indirect comparisons of different drugs in the joint cavity makes it difficult to have a clearer and more comprehensive understanding of joint cavity injection methods. In this study, the efficacy of platelet-rich, ozone, sodium hyaluronate, and combined knee cavity injections were compared directly or indirectly using a reticulated meta-analysis in this field, and the efficacy of treatment measures was ranked to provide more comprehensive and reliable evidence-based clinical evidence for the selection of knee cavity injections in osteoarthritis of the knee.Objective:To compare the effects of platelet-rich plasma, ozone, and sodium glassate injection interventions on the efficacy of osteoarthritis of the knee through reticulated Meta-analysis, and to comprehensively compare the clinical effectiveness of platelet-rich plasma, ozone, and sodium glassate injection joint cavity injection for the treatment of osteoarthritis of the knee.Methods:The PubMed, CBM, CNKI, VIP, and Wan-Fang databases were searched for information on the effectiveness of platelet-rich plasma, ozone, and sodium vitrate injection for the comparative treatment of osteoarthritis of the knee, with a search time frame of each database from the date of creation to July 20, 2021. Two investigators independently screened the literature, extracted data according to inclusion and exclusion criteria, and evaluated the quality of the literature in parallel. Statistical analysis was performed using Stata 16.0 software to compare the differences in the efficacy of each treatment measure using the ratio and 95% confidence interval as effect indicators and to rank the efficacy.Results:Thirty-three RCTs with 7003 patients with osteoarthritis of the knee were included, involving 5 therapeutic measures. Meta-analysis showed that the efficacy of platelet-rich plasma injection was superior to both ozone and hyaluronic acid therapies. Hyaluronic acid+ozone and platelet-rich plasma+hyaluronic acid were both superior to ozone and hyaluronic acid monotherapy. The differences in efficacy between hyaluronic acid and ozone compared with platelet-rich plasma were statistically significant, and the differences in efficacy between the 2 combination therapies (platelet-rich plasma+hyaluronic acid, hyaluronic acid+ozone) and the 3 monotherapies (platelet-rich plasma, ozone, hyaluronic acid) were statistically significant. Platelet-rich plasma+hyaluronic acid, hyaluronic acid+ozone compared with 3 monotherapies (platelet-rich plasma, ozone, hyaluronic acid) were statistically significant, except for the difference in efficacy with platelet-rich plasma, which was not statistically significant, indicating that this platelet-rich plasma+hyaluronic acid and Hyaluronic acid+ozone combination therapy was superior to monotherapy. Also, the efficacy of platelet-rich plasma was better than hyaluronic acid and ozone and the difference was statistically significant, indicating that platelet-rich plasma was more effective than ozone and sodium glass in the treatment of osteoarthritis of the knee in monotherapy.Conclusion:It is believed that in the course of clinical practice, hyaluronic acid+ozone or platelet-rich plasma+hyaluronic acid combination therapy or platelet-rich plasma therapy can be preferred for patients with osteoarthritis of the knee. 相似文献
36.
目的 探讨项目管理在提高门诊肠镜患者肠道准备合格率中的应用效果.方法 成立项目管理团队,对门诊肠镜患者肠道准备合格率进行调查,找出影响合格率亟待改进的问题,实施项目管理,项目管理运用后再次进行调查,将调查结果与实施前进行比较.结果 项目管理实施后门诊肠镜患者肠道准备合格率显著高于实施前(P<0.01).结论 实施项目管... 相似文献
37.
Xinmeng Liao Yawen Lan Rui Shao Jiayu Liu Shufei Liang Zhan Yin Gudmundur H. Gudmundsson Peter Bergman Min Wan 《Journal of innate immunity》2022,14(3):229
Vitamin D (VD) is a major regulator of calcium metabolism in many living organisms. In addition, VD plays a key role in regulating innate and adaptive immunity in vertebrates. Neutrophils constitute an important part of the first line of defense against invading microbes; however, the potential effect of VD on neutrophils remains elusive. Thus, in this study zebrafish in different developmental stages were utilized to identify the potential role of VD in the basal homeostasis and functions of neutrophils. Our results showed that addition of exogenous VD<sub>3</sub> promoted granulopoiesis in zebrafish larvae. Reciprocally, neutrophil abundance in the intestine of adult zebrafish with a cyp2r1 mutant, lacking the capacity to 25-hydroxylate VD, was reduced. Moreover, VD-mediated granulopoiesis was still observed in gnotobiotic zebrafish larvae, indicating that VD regulates neutrophil generation independent of the microbiota during early development. In contrast, VD was incapable to influence granulopoiesis in adult zebrafish when the commensal bacteria were depleted by antibiotic treatment, suggesting that VD might modulate neutrophil activity via different mechanisms depending on the developmental stage. In addition, we found that VD<sub>3</sub> augmented the expression of il-8 and neutrophil recruitment to the site of caudal fin amputation. Finally, VD<sub>3</sub> treatment significantly decreased bacterial counts and mortality in zebrafish infected with Edwardsiella tarda (E. tarda) in a neutrophil-dependent manner. Combined, these findings demonstrate that VD regulates granulopoiesis and neutrophil function in zebrafish immunity. 相似文献
38.
目的:研究荞麦花叶提取物(extraction of buckwheat flower and leaf,EBFL)对肿瘤的辅助治疗作用,并探讨其可能的机制。方法:建立小鼠S180肿瘤模型;分别ig荞麦花叶提取物200,400 mg.kg-1及与环磷酰胺(CTX)联合给药14 d,实验重复3次。测定荷瘤小鼠的生存期、肿瘤抑制率、白细胞计数、胸腺指数、脾指数,同时测定荷瘤小鼠血清中白细胞介素-2(IL-2),肿瘤坏死因子-α(TNF-α)水平。结果:与模型组相比,EBFL对肿瘤抑制作用不明显,但可使荷瘤小鼠生存期明显延长,25 d生存率以CTX+EBFL-H组最高(35%),其次是EBFL-H(25%)和EBFL-L(20%);与CTX阳性对照组比较,EBFL能明显抑制CTX所致白细胞数量减少及免疫器官指数降低(P<0.05,P<0.01);EBFL可提高IL-2水平,但对TNF-α水平无影响。结论:EBFL可改善荷瘤小鼠生存质量,延长生存期,减轻CTX的毒性,其机制可能是通过提高机体免疫力实现的。 相似文献
39.
40.
生地对大鼠肺间质成纤维细胞Ⅰ、Ⅲ型胶原表达的作用 总被引:3,自引:0,他引:3
目的研究生地对原代分离的大鼠肺间质成纤维细胞(fibroblast,fb)Ⅰ、Ⅲ型胶原(Col Ⅰ、Col Ⅲ)表达的影响.方法生地经提取分离后得到不同部位的提取物.大鼠肺间质成纤维细胞经原代分离传代后,加入不同浓度的生地提取物及生地注射液作用72 h,采用RT-PCR的方法测定其中Ⅰ、Ⅲ型胶原的量.结果水提醇沉上清液中以低聚糖为主的部分除个别浓度外,其余浓度对col Ⅰ表达均有抑制作用,高浓度对C0l Ⅲ表达有一定的抑制作用;醇沉沉淀部分2×10-2g/mL的浓度对col Ⅰ表达抑制作用明显,各浓度对Col Ⅲ表达均有抑制作用;生地注射液各浓度均对col Ⅰ的表达均有抑制作用,低浓度(5×10-3g/mL)对coI Ⅰ、Col Ⅲ表达均有明显抑制作用.结论生地中某些成分能够抑制大鼠肺间质成纤维细胞Col Ⅰ、Col Ⅲ的表达,是生地对肺纤维化起治疗作用的机制之一. 相似文献