全文获取类型
收费全文 | 14250篇 |
免费 | 1063篇 |
国内免费 | 394篇 |
专业分类
耳鼻咽喉 | 96篇 |
儿科学 | 107篇 |
妇产科学 | 100篇 |
基础医学 | 2593篇 |
口腔科学 | 746篇 |
临床医学 | 1147篇 |
内科学 | 2841篇 |
皮肤病学 | 171篇 |
神经病学 | 631篇 |
特种医学 | 396篇 |
外科学 | 1061篇 |
综合类 | 1140篇 |
预防医学 | 1007篇 |
眼科学 | 121篇 |
药学 | 1606篇 |
1篇 | |
中国医学 | 750篇 |
肿瘤学 | 1193篇 |
出版年
2024年 | 46篇 |
2023年 | 260篇 |
2022年 | 1133篇 |
2021年 | 1391篇 |
2020年 | 618篇 |
2019年 | 623篇 |
2018年 | 591篇 |
2017年 | 516篇 |
2016年 | 519篇 |
2015年 | 586篇 |
2014年 | 939篇 |
2013年 | 1059篇 |
2012年 | 665篇 |
2011年 | 852篇 |
2010年 | 516篇 |
2009年 | 631篇 |
2008年 | 589篇 |
2007年 | 547篇 |
2006年 | 512篇 |
2005年 | 390篇 |
2004年 | 299篇 |
2003年 | 290篇 |
2002年 | 226篇 |
2001年 | 190篇 |
2000年 | 145篇 |
1999年 | 133篇 |
1998年 | 141篇 |
1997年 | 121篇 |
1996年 | 112篇 |
1995年 | 106篇 |
1994年 | 94篇 |
1993年 | 70篇 |
1992年 | 80篇 |
1991年 | 73篇 |
1990年 | 70篇 |
1989年 | 66篇 |
1988年 | 41篇 |
1987年 | 41篇 |
1986年 | 37篇 |
1985年 | 63篇 |
1984年 | 54篇 |
1983年 | 49篇 |
1982年 | 57篇 |
1981年 | 38篇 |
1980年 | 26篇 |
1979年 | 21篇 |
1978年 | 23篇 |
1977年 | 9篇 |
1976年 | 20篇 |
1975年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
181.
Andrea Bernini Ottavia Spiga Arianna Ciutti Maria Scarselli Giuseppe Bottoni Paolo Mascagni Neri Niccolai 《European journal of pharmaceutical sciences》2004,22(5):445-450
A 1H and 13C NMR study on the inclusion complex of paroxetine with β-cyclodextrin was carried out in order to define the stoichiometry of the association and its strength. Proton and carbon chemical shift measurements of paroxetine and β-cyclodextrin were performed at several molar ratios and temperatures, allowing the determination of a 1:1 stoichiometry and an association constant value of the order of 2 × 103 for the paroxetine–β-cyclodextrin complex. Overhauser effects in the rotating frame were also measured, and the experimental interproton distance constraints have been used for molecular model building of the complex. The obtained model indicates that the benzodioxolyl moiety of paroxetine is deeply inserted in the cavity of the cylindrical structure of β-cyclodextrin, while the fluoro-phenyl ring lays above the wider rim. 相似文献
182.
目的 探讨CCLG-ALL2008方案治疗具有不同分子生物学特征的初诊儿童急性淋巴细胞白血病(ALL)的长期疗效。方法 选取按照CCLG-ALL2008方案治疗的940例初诊ALL患儿为研究对象,针对不同分子生物学特征ALL的长期疗效进行回顾性分析。结果 940例ALL患儿中,男570例,女370例,中位年龄5(1~15)岁,中位随访时间65(3~123)个月。完全缓解(CR)率为96.7%,预期10年总体生存(OS)率为(76.5±1.5)%,无事件生存(EFS)率为(62.6±3.0)%。患儿经治疗达CR后,总复发率为21.9%,其中ETV6-RUNX1阳性患儿复发率最低,且易于晚期复发;MLL重排阳性患儿复发率最高,且易于早期复发。ETV6-RUNX1阳性患儿的预期10年OS率明显高于伴有TCF3-PBX1阳性、BCR-ABL阳性、MLL重排及无分子生物学特征患儿(P < 0.05)。ETV6-RUNX1阳性患儿的预期10年EFS率明显高于伴有BCR-ABL阳性和MLL重排患儿(P < 0.05)。结论 分子生物学特征是影响ALL患儿长期预后的指标,MLL重排、BCR-ABL融合基因阳性是预后的不良指标,ETV6-RUNX1融合基因阳性患儿长期生存率较高。 相似文献
183.
Amparo Rodríguez Sánchez María J. Chueca Guindulain María Alija Merillas Susana Ares Segura José Carlos Moreno Navarro María Dolores Rodríguez Arnao 《Anales de pediatría (Barcelona, Spain : 2003)》2019,90(4):250.e1-250.e8
The screening program of congenital hypothyroidism (CH) is probably one of the best achievements in paediatrics. Thyroid hormones are essential for brain development and brain maturation that continue through the neonatal period. Hypothyroidism that begins in the first months of life causes irreversible damage to the central nervous system, and is one of the most frequent and preventable causes of mental retardation. As children with congenital hypothyroidism are born with a normal appearance, analytical studies are required to immediately start the appropriate therapy.This article analyses the aims, diagnostic procedures, tests required, aetiology, and differential diagnosis in this disorder. Especially relevant is to perform frequent monitoring to ensure dose adjustments of L-Thyroxine therapy, avoiding infra- or supra-dosing that negatively affects neurosensory functions. Re-evaluation of the aetiology permanent vs transient hypothyroidism is always recommended after 3 years of chronological age.The relevance of this screening program should be widely discussed in paediatrics. The main objective is to avoid cerebral damage in these patients, and has been highly successful and economically beneficial.Other aspects are required to optimise patient outcomes, to perform all the controls according to the recommendations and to include, in the near future, the diagnosis of central hypothyroidism. Implementation of this program is necessary to progress in accordance with current scientific knowledge. 相似文献
184.
Mireia Orgilés Silvia Melero Patricia Penosa José Pedro Espada Alexandra Morales 《Anales de pediatría (Barcelona, Spain : 2003)》2019,90(5):263-271
IntroductionAlthough several tools have been developed to assess general HRQoL in children, parental reports are required to supplement this information, especially in very young children. The parents version of the Kiddy-KINDL-R was developed to assess HRQoL in children aged 3 to 7 years through the reports of their parents or legal guardians.ObjectiveThe aim of this study was to validate the parents version of the Kiddy-KINDL-R questionnaire and assess its psychometric properties in a sample of Spanish preschool-aged children.MethodCross-sectional study in 283 parents or legal guardians of children aged 3 to 6 years that completed the Kiddy-KINDL-R questionnaire and an additional scale to assess anxiety problems. We performed confirmatory factor analysis to assess whether the original Kiddy-KINDL-R version fit the Spanish data; we assessed internal consistency by means of the ordinal alpha and the discriminant validity by means of the Preschool Anxiety Scale.ResultsAlthough the original six-factor model showed a good fit, we propose a model consisting of 22 items and the same 6 factors for the Spanish version. The reliability was excellent, and the internal consistency values were adequate. Our results showed significant negative correlations between the Kiddy-KINDL-R and the external anxiety measure, which was evidence of discriminant validity.ConclusionWe demonstrated that the Spanish version of the Kiddy-KINDL-R had good psychometric properties and that this questionnaire is an adequate assessment tool that could be useful in clinical practice. 相似文献
185.
The overexpression of cyclooxygenase-2 (COX-2) was correlated with the invasion and lymphatic metastasis and with the clinical stage of Nasopharyngeal carcinoma (NPC). The C allele of COX-2 gene rs5275 polymorphism disrupts miR-542-3p function to promote COX-2 overexpression. To examine the role of COX-2 gene rs5275 polymorphism in NPC, we determined COX-2 gene rs5275 polymorphism by using a custom-by-design 48-Plex single nucleotide polymorphism (SNP) Scan? Kit. We found that C allele or CC genotype of rs5275 polymorphism in COX-2 gene was associated with an increased risk of NPC. In stratified analyses, COX-2 gene rs5275 polymorphism was associated with the risk of NPC among females, smokers, and drinkers. Based on these results, we concluded that COX-2 gene rs5275 variant contributes to NPC risk in a Chinese population. Larger studies with more diverse ethnic populations are needed to confirm these results. 相似文献
186.
Ahwon Lee Sung-Hak Lee Chan Kwon Jung Gyungsin Park Kyo Young Lee Hyun Joo Choi Ki Ouk Min Tae Jung Kim Eun Jung Lee Youn Soo Lee 《Pathology, research and practice》2018,214(5):713-719
Targeted application of next-generation sequencing (NGS) technology allows detection of specific mutations that can provide treatment opportunities for cancer patients. We evaluated the applicability of the Ion AmpliSeq Cancer Hotspot Panel V2 (CHV2) using formalin-fixed, paraffin-embedded (FFPE) tissue of clinical specimens.Thirty-five FFPE tumour samples with known mutational status were collected from four different hospitals and sequenced with CHV2 using an Ion Chef System and Ion S5 XL system. Out of 35 cases, seven were sequenced with Oncomine focus Assay Panel for comparison. For the limit of detection test, we used an FFPE reference standard, a cell line that included an engineered 50% EGFR T790?M in an RKO cell line background. Coverage analysis results including number of mapped reads, on target percent, mean depth, and uniformity were not different according to hospitals. Sensitivity for mutation detection down to 3% was demonstrated. NGS results showed 100% concordance with the results from single molecular pathology tests Assay in 30 cases with 24 known positive mutations and 14 known negative mutations, and another NGS panel of the Oncomine focus in seven cases.The CHV2 NGS test for solid tumours using Ion chef system and S5 XL system in clinical molecular pathology laboratories for analysis of solid tumours could be routinely used and could replace some single molecular pathology tests after a stringent and thorough validation process. 相似文献
187.
An estimated rise in liver cancer incidence will increase to 95374 new cases by 2020. Hepatocellular Carcinoma (HCC), the most common primary malignant tumour of the liver, is considered to be the third leading cause of all cancer-related deaths and fifth common cancer worldwide. The reported data shows that the rate of HCC incidence in male population is three to four times higher compared with the female population. In the United States, HCV-induced liver cancer is increasing very fast because of the lack of proper treatment option. There are various treatment strategies available for HCC like liver transplantation, resection, ablation, embolization and chemotherapy still the prognosis is destitute. If the patient is eligible, liver transplantation is the only therapeutic option that may give around 90% survival rate, but the scarcity of liver donor limits its broad applicability. A sudden address is necessary to develop specific drugs, personalized medicine, for HCC. 相似文献
188.
Urothelial carcinoma is the fourth most common tumors after prostate cancer, lung, and colorectal carcinoma but the second most common urologic malignancy. Urothelial carcinoma composed more than 90% of bladder tumors while squamous cell carcinoma and adenocarcinomas composed 5% and 2% respectively. The intense research involving the different molecular aspects of bladder cancer has provided a great insight into identifying more about molecular profiling and pathways of bladder cancer.In this review, we will highlight the general concepts of the molecular features; profiling and classification as well as the molecular pathways for bladder carcinomas, especially urothelial carcinoma. Also, we will discuss the advances of molecular biomarkers for screening, early diagnosis, surveillance and potential prognosis of urothelial carcinoma of the bladder. Studies showed that accumulation of genetic alterations involving the clonal expansion of altered cells with growth advantages through sequential multi-step pathways results in progression of bladder tumors.The accumulated research data from literature has revealed that the genomic signatures of urothelial carcinoma are required to subclassify bladder cancer into genetically distinct subgroups. These findings could improve the understating of pathogenesis as well as will provide new therapeutic modules e.g. targeted therapy. 相似文献
189.
《Chemical biology & drug design》2018,91(2):620-630
Estrogen receptor (ER) has been a therapeutic target to treat ER‐positive breast cancer, most notably by agents known as selective estrogen receptor modulators (SERMs). However, resistance and severe adverse effects of known drugs gave impetus to the search for newer agents with better therapeutic profile. ERα and ERβ are two isoforms sharing 56% identity and having different physiological functions and expressions in various tissues. Only two residues differ in the active sites of the two isoforms motivating us to design isoform‐selective ligands. Guided by computational docking and molecular dynamics simulations, we have designed, synthesized, and tested, substituted biphenyl‐2,6‐diethanones and their derivatives as potential agents targeting ERα. Four of the molecules synthesized exhibited preferential cytotoxicity in ERα+ cell line (MCF‐7) compared to ERβ+ cell line (MDA‐MB‐231). Molecular dynamics (MD) in combination with molecular mechanics‐generalized Born surface area (MM‐GBSA) methods could account for binding selectivity. Further cotreatment and E‐screen studies with known ER ligands—estradiol (E2) and tamoxifen (Tam)—indicated isoform‐selective anti‐estrogenicity in ERα+ cell line which might be ER‐mediated. ERα siRNA silencing experiments further confirmed the ER selective nature of ligands. 相似文献
190.
Gentian violet (GV) is a well-known triarylmethane dye that is used in aquacultural, industrial and medicinal fields. But concerns in growing number have been paid to its potential health problems to human beings and its hazardous effects to environment. Herein, the toxic interaction of GV with bovine hemoglobin (BHb) was investigated by a series of spectroscopic methods and molecular modeling method. The fluorescence emission profile exhibited a remarkable quenching upon addition of GV to the buffered aqueous solution of BHb and the analysis of results revealed the dominant role of static quenching mechanism in GV–BHb interaction. The negative ΔH and positive ΔS values demonstrated that the electrostatic interactions mainly stabilized this toxicantprotein complex. Synchronous fluorescence, UV–Vis absorption and CD spectroscopic studies proved that the conformational change of BHb was induced by GV’s combination. Molecular modeling studies exhibited the binding mode of GV–BHb complex and the detailed information of related driving forces. During the 1H nuclear magnetic resonance spectra (1H NMR) study, the chemical shift perturbation and spin–lattice relaxation times of different protons were further used to investigate the interaction of GV with BHb and the results indicated that GV bound orientationally to BHb. 相似文献