全文获取类型
收费全文 | 19957篇 |
免费 | 1006篇 |
国内免费 | 575篇 |
专业分类
耳鼻咽喉 | 65篇 |
儿科学 | 201篇 |
妇产科学 | 358篇 |
基础医学 | 2666篇 |
口腔科学 | 388篇 |
临床医学 | 1472篇 |
内科学 | 3014篇 |
皮肤病学 | 157篇 |
神经病学 | 1138篇 |
特种医学 | 182篇 |
外国民族医学 | 8篇 |
外科学 | 1160篇 |
综合类 | 2798篇 |
现状与发展 | 2篇 |
预防医学 | 817篇 |
眼科学 | 289篇 |
药学 | 4520篇 |
9篇 | |
中国医学 | 1407篇 |
肿瘤学 | 887篇 |
出版年
2023年 | 274篇 |
2022年 | 418篇 |
2021年 | 713篇 |
2020年 | 876篇 |
2019年 | 592篇 |
2018年 | 555篇 |
2017年 | 743篇 |
2016年 | 857篇 |
2015年 | 687篇 |
2014年 | 1650篇 |
2013年 | 2736篇 |
2012年 | 1996篇 |
2011年 | 1766篇 |
2010年 | 1330篇 |
2009年 | 1177篇 |
2008年 | 955篇 |
2007年 | 586篇 |
2006年 | 462篇 |
2005年 | 417篇 |
2004年 | 335篇 |
2003年 | 245篇 |
2002年 | 155篇 |
2001年 | 115篇 |
2000年 | 77篇 |
1999年 | 79篇 |
1998年 | 111篇 |
1997年 | 102篇 |
1996年 | 81篇 |
1995年 | 75篇 |
1994年 | 82篇 |
1993年 | 46篇 |
1992年 | 66篇 |
1991年 | 51篇 |
1990年 | 56篇 |
1989年 | 49篇 |
1988年 | 43篇 |
1987年 | 37篇 |
1986年 | 45篇 |
1985年 | 118篇 |
1984年 | 136篇 |
1983年 | 106篇 |
1982年 | 126篇 |
1981年 | 77篇 |
1980年 | 74篇 |
1979年 | 57篇 |
1978年 | 33篇 |
1977年 | 35篇 |
1976年 | 35篇 |
1975年 | 33篇 |
1973年 | 31篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
1.
María C. Lanuza-López Sandra G. Martínez-Garza Jesús F. Solórzano-Vázquez Daniela Paz-Cervantes Claudia González-Ortega Israel Maldonado-Rosas 《Gynecological endocrinology》2020,36(9):829-834
AbstractOocyte maturation defect is a challenging situation in the management of infertility, the etiology may be related to endocrine causes, protocols used in ovarian stimulation, oocyte intrinsic defects or procedures in embryology laboratory. We report three Mexican females in treatment for primary infertility with non-mature oocytes after ovary stimulation and oocyte capture in whom a genetic diagnosis of TUBB8-oocyte maturation defect was revealed by exome sequencing. Two couples achieved pregnancies though oocyte donation after establishing the genetic etiology. Our results expand the role of TUBB8-disorders in patients of non-Asian ethnicity. Oocyte maturation defects of monogenic origin are a growing group of disorders that endocrinologists and reproductive medicine specialists should be aware in order to provide referral to genetics for establish a correct and opportune diagnosis. 相似文献
2.
3.
《Saudi Pharmaceutical Journal》2022,30(6):655-668
Most vaccines approved by regulatory bodies are administered via intramuscular or subcutaneous injections and have shortcomings, such as the risk of needle-associated blood infections, pain and swelling at the injection site. Orally administered vaccines are of interest, as they elicit both systemic and mucosal immunities, in which mucosal immunity would neutralize the mucosa invading pathogen before the onset of an infection. Hence, oral vaccination can eliminate the injection associated adverse effects and enhance the person's compliance. Conventional approaches to manufacturing oral vaccines, such as coacervation, spray drying, and membrane emulsification, tend to alter the structural proteins in vaccines that result from high temperature, organic and toxic solvents during production. Electrohydrodynamic processes, specifically electrospraying, could solve these challenges, as it also modulates antigen release and has a high loading efficiency. This review will highlight the mucosal immunity and biological basis of the gastrointestinal immune system, different oral vaccine delivery approaches, and the application of electrospraying in vaccines development. 相似文献
4.
Signaling by the transforming growth factor-β (TGF-β) superfamily is important in the regulation of hematopoiesis and is dysregulated in myelodysplastic syndromes (MDS), contributing to ineffective hematopoiesis and clinical cytopenias. TGF-β, activins and growth differentiation factors exert inhibitory effects on red cell formation by activating canonical SMAD2/3 pathway signaling. SMAD2/3 overactivation is seen in numerous subtypes of MDS. Furthermore, reduced levels of inhibitory SMAD7 are 相似文献
References
- 1.Valcarcel D, Verma A, Platzbecker U, et al. Phase 2 Study of Monotherapy Galunisertib (LY2157299 Monohydrate) in Very Low-, Low-, and Intermediate-Risk Patients with Myelodysplastic Syndromes. Blood. 2015;126:1669.
- 2.Suragani RN, Cawley SM, Li R, Wallner S, et al. Modified activin receptor IIB ligand trap mitigates ineffective erythropoiesis and disease complications in murine β-thalassemia. Blood. 2014 Jun 19;123(25):3864-72.
- 3.Dussiot M, Maciel TT, Fricot A, et al. Nat Med. 2014 Apr;20(4):398-407.
- 4.
5.
Caveolin-1 (Cav-1) appears to be both a pathophysiological contributor and a target in different inflammatory and hyperproliferative skin conditions as well as in skin aging. Skin fibroblasts demonstrate an up-regulation of Cav-1 expression both in chronological and UV-induced aging, and such an up-regulation was observed both in vitro and in vivo. Typical alterations in aging skin involve a reduction of the dermis thickness, a significant expansion of the dermal white adipose tissue as well as modifications of the content and distribution of hyaluronan, impairment of autophagic flux, a reduction of collagen expression and an increase in tissue inflammation. All of these phenomena can be connected with changes in Cav-1 expression in the aging skin. Modified expression of Cav-1 can also significantly influence the mechanical properties of individual skin layers, thus changing the total mechanical stability of the layered composite skin/WAT, leading to typical structural modifications of the skin surface in the aging skin. Selective reduction of Cav-1 expression has the potential to exert anti-aging effects on the skin. 相似文献
6.
目的 探讨在苯妥英钠(Phenytoin,PHT)促进大鼠牙周膜干细胞(Rat periodontal ligament stem cells,rPDLSCs)、大鼠骨髓间充质干细胞(Rat Bone Marrow Mesenchymal Stem Cells,rBMMSCs)黏附于牙骨质过程中,整合素α5β1(Integrin α5β1)起到的作用。方法 提取大鼠BMMSCs和PDLSCs,培养并纯化。通过细胞鉴定后,将获得的两种细胞各分为4组:40 mg/L PHT处理组、40 mg/L PHT+整合素α5抗体处理组、40 mg/L PHT+整合素β1抗体处理组、PBS处理组,每组细胞放入置有牙骨质片的96孔板处理4 h后,检测黏附于牙骨质片上的细胞量并做以比较。最后,利用qRT-PCR和Western blot检测40 mg/L PHT组与对照组细胞的整合素α5、β1亚基的mRNA与蛋白表达量。结果 40 mg/L PHT可促进rBMMSCs及rPDLSCs黏附于牙骨质片,加入整合素α5、β1抗体后,均明显抑制了40 mg/L PHT对rBMMSCs、rPDLSCs黏附于牙骨质的促进作用(P<0.01)。qRT-PCR、Western-blot结果显示PHT处理组的整合素α5、β1亚基表达量高于空白对照组(P<0.05)。结论 40 mg/L PHT能促进rBMMSCs、rPDLSCs黏附于牙骨质,该作用与整合素α5β1的表达上调密切相关。 相似文献
7.
《Saudi Pharmaceutical Journal》2022,30(6):669-678
BackgroundIschemia reperfusion (I/R) play an imperative role in the expansion of cardiovascular disease. Sinomenine (SM) has been exhibited to possess antioxidant, anticancer, anti-inflammatory, antiviral and anticarcinogenic properties. The aim of the study was scrutinized the cardioprotective effect of SM against I/R injury in rat.MethodsRat were randomly divided into normal control (NC), I/R control and I/R + SM (5, 10 and 20 mg/kg), respectively. Ventricular arrhythmias, body weight and heart weight were estimated. Antioxidant, inflammatory cytokines, inflammatory mediators and plasmin system indicator were accessed.ResultsPre-treated SM group rats exhibited the reduction in the duration and incidence of ventricular fibrillation, ventricular ectopic beat (VEB) and ventricular tachycardia along with suppression of arrhythmia score during the ischemia (30 and 120 min). SM treated rats significantly (P < 0.001) altered the level of antioxidant parameters. SM treatment significantly (P < 0.001) repressed the level of creatine kinase MB (CK-MB), creatine kinase (CK) and troponin I (Tnl). SM treated rats significantly (P < 0.001) repressed the tissue factor (TF), thromboxane B2 (TXB2), plasminogen activator inhibitor 1 (PAI-1) and plasma fibrinogen (Fbg) and inflammatory cytokines and inflammatory mediators.ConclusionOur result clearly indicated that SM plays anti-arrhythmia effect in I/R injury in the rats via alteration of oxidative stress and inflammatory reaction. 相似文献
8.
Michael M Gezalian Luigi Mangiacotti Padmesh Rajput Nicklaus Sparrow Konrad Schlick Shouri Lahiri 《Journal of cerebral blood flow and metabolism》2021,41(4):693
Adrenoceptor and calcium channel modulating medications are widely used in clinical practice for acute neurological and systemic conditions. It is generally assumed that the cerebrovascular effects of these drugs mirror that of their systemic effects – and this is reflected in how these medications are currently used in clinical practice. However, recent research suggests that there are distinct cerebrovascular-specific effects of these medications that are related to the unique characteristics of the cerebrovascular anatomy including the regional heterogeneity in density and distribution of adrenoceptor subtypes and calcium channels along the cerebrovasculature. In this review, we critically evaluate existing basic science and clinical research to discuss known and putative interactions between adrenoceptor and calcium channel modulating pharmacotherapies, the neurovascular unit, and cerebrovascular anatomy. In doing so, we provide a rationale for selecting vasoactive medications based on lesion location and lay a foundation for future investigations that will define neuroprotective paradigms of adrenoceptor and calcium channel modulating therapies to improve neurological outcomes in acute neurological and systemic disorders. 相似文献
9.
10.
The Clinical and Prognostic Implications of Pluripotent Stem Cell Markers Expression and Their Correlation with the WNT signal pathway in Hepatocellular Carcinoma 下载免费PDF全文
Nisreen A.A. OsmanAlzahraa Ibrahim KhalilRehab Kamal Yousef 《Asian Pacific journal of cancer prevention》2020,21(10):2961-2970
Objectives: This study aimed to investigate the expression of SOX2, SOX9, p53, and β-catenin in hepatocellular carcinoma (HCC) and their correlation with clinicopathological parameters of prognostic importance. Materials and Methods: Seventy-five patients were enrolled in this study. All patients had full clinical and follow-up data and available paraffin blocks. Immunohistochemical analysis was performed and correlated with clinicopathological factors and patient survival. Results: We detected the positive expression of SOX2, SOX9, p53, and β-catenin in 76%, 50.7%, 50.7%, and 77.9% of HCC specimens respectively. All studied markers showed a significant increase in the expression in tumor tissue specimens compared to non-tumor tissue. Both SOX2 and SOX9 expressions were significantly associated with adverse prognostic factors in HCC. Significant positive correlations were found between SOX2 and SOX9 and both p53 and β-catenin expression (r= 0.528, 0.485 and; r = 0.253, 0.327, respectively; p < 0.0001 for both of them). Regarding survival, we found that HCC patients with positive SOX2 and SOX9 expressions had significantly shorter overall survival (p=0.0001, each). Additionally, larger tumor size, tumor grade, high stage, tumor multiplicity, presence of cirrhosis, tumor necrosis, high p53 expression, and positive β-catenin expression were independent predictors of worse survival. A multivariate Cox analysis revealed that tumor grade, stage, p53, and SOX2 expression were independent predictors of unfavorable prognosis in overall survival (p=0.0001, p=0.0001,p=0.033; and p=0.003, respectively). Conclusions: Our findings might provide an insight into SOX2 and SOX9’s role in HCC and suggest that SOX2 might be targeted for HCC therapy. 相似文献