全文获取类型
收费全文 | 916篇 |
免费 | 33篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 7篇 |
儿科学 | 37篇 |
妇产科学 | 81篇 |
基础医学 | 143篇 |
口腔科学 | 3篇 |
临床医学 | 54篇 |
内科学 | 186篇 |
皮肤病学 | 9篇 |
神经病学 | 57篇 |
特种医学 | 26篇 |
外科学 | 53篇 |
综合类 | 12篇 |
预防医学 | 86篇 |
眼科学 | 7篇 |
药学 | 115篇 |
肿瘤学 | 77篇 |
出版年
2023年 | 5篇 |
2022年 | 24篇 |
2021年 | 46篇 |
2020年 | 15篇 |
2019年 | 16篇 |
2018年 | 18篇 |
2017年 | 29篇 |
2016年 | 30篇 |
2015年 | 27篇 |
2014年 | 35篇 |
2013年 | 58篇 |
2012年 | 68篇 |
2011年 | 62篇 |
2010年 | 31篇 |
2009年 | 29篇 |
2008年 | 68篇 |
2007年 | 83篇 |
2006年 | 49篇 |
2005年 | 66篇 |
2004年 | 54篇 |
2003年 | 50篇 |
2002年 | 41篇 |
2001年 | 5篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 4篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1993年 | 4篇 |
1992年 | 1篇 |
1991年 | 4篇 |
1990年 | 1篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1980年 | 3篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1973年 | 4篇 |
1971年 | 1篇 |
1968年 | 1篇 |
1931年 | 1篇 |
排序方式: 共有953条查询结果,搜索用时 0 毫秒
941.
Opalinska M Stompor T Pach D Mikolajczak R Fedak D Krzanowski M Rakowski T Sowa-Staszczak A Glowa B Garnuszek P Maurin M Karczmarczyk U Sulowicz W Hubalewska-Dydejczyk A 《European journal of nuclear medicine and molecular imaging》2012,39(4):673-682
Purpose
Identification of vulnerable plaques remains crucial for better cardiovascular risk assessment. At least 20% of inflammatory cells within unstable (vulnerable) plaques comprise T lymphocytes, which contain receptors for interleukin-2 (IL-2); those receptors can be identified by scintigraphy with radiolabelled IL-2.The aim of this study was to identify the “inflamed” (vulnerable) plaques by scintigraphy using IL-2 labelled with 99mTc in the selected, high cardiovascular risk group of end-stage renal disease (ESRD) patients.Methods
A total of 28 patients (18 men, 10 women, aged 55.2?±?9.6?years, 17 on peritoneal dialysis, 11 on haemodialysis) underwent common carotid artery (CCA) scintigraphy with the use of 99mTc-hydrazinonicotinamide (HYNIC)-IL-2. In all cases, ultrasound examination of the CCA was performed and levels of selected proinflammatory factors, atherogenic markers and calcium-phosphate balance parameters were measured. Finally, the target to non-target (T/nT) ratio of IL-2 uptake in atherosclerotic plaques with intima-media thickness (IMT), classic cardiovascular risk factors and concentrations of the measured factors were compared.Results
Increased 99mTc-HYNIC-IL-2 uptake in atherosclerotic plaques in 38/41 (91%) cases was detected. The median T/nT ratio of focal 99mTc-HYNIC-IL-2 uptake in atherosclerotic plaques was 2.35 (range 1.23–3.63). The mean IMT value on the side of plaques assessed by scintigraphy was 0.79?±?0.18?mm (median 0.8, range 0.5–1.275). Correlations between T/nT ratio and homocysteine (R?=?0.22, p?=?0.037), apolipoprotein B (apoB) (R?=?0.31, p?=?0.008), apoB to apoA-I ratio (R?=?0.29, p?=?0.012) and triglyceride concentration (R?=?0.26, p?=?0.021) were detected. A lower T/nT ratio in patients with better parameters of nutritional status (haemoglobin, albumin, adiponectin) in comparison with patients with worse nutritional parameters (3.20?±?0.5 vs 2.16?±?0.68, p?=?0.025) was revealed as well as a difference between values of T/nT ratio in groups of patients with values of apoB, soluble CD40 ligand and asymmetric dimethylarginine above and below median (3.18?±?0.52 vs 2.16?±?0.68, p?=?0.031). No statistically significant association was found between T/nT ratio and mean value of either IMT or classic cardiovascular risk factors.Conclusion
Scintigraphy with the use of 99mTc-HYNIC-IL-2 can be a tool for inflamed atherosclerotic (vulnerable) plaque visualization within CCA in ESRD patients. Quantitative results of carotid artery scintigraphy with 99mTc-HYNIC-IL-2 correlate with serum concentration of selected cardiovascular risk markers. 相似文献942.
943.
Skalska U Kontny E Prochorec-Sobieszek M Maslinski W 《Rheumatology (Oxford, England)》2012,51(10):1757-1764
Objectives. To evaluate the chondrogenic potential, phenotype and percentage of IA adipose-derived mesenchymal stem cells (ADSCs) from RA patients in comparison with OA patients. The effect of TNF treatment on ADSC differentiation was also examined. Methods. Adipose tissue was obtained from RA and OA patients. ADSCs were isolated and cultured until passage 4. After that period, the phenotype and percentage of these cells were analysed by flow cytometry. Passage 4 cells were cultured in chondrogenic medium with or without TNF. After 3 weeks of differentiation the expression of Sox9, aggrecan (Acan) and collagen 2a (Col2a) mRNA was assessed by RT-PCR and GAG deposition by alcian blue staining. Results. The phenotype and percentage of ADSCs were similar in both RA and OA. The results of alcian blue staining showed effective chondrogenesis in RA and OA ADSCs. TNF inhibited GAG deposition in both RA and OA samples similarly. Sox9, Acan and Col2a mRNA expression was significantly increased in chondrogenic-medium-treated cells (P?0.05) and decreased after TNF exposure (P?0.01). No statistically significant differences between RA and OA were observed. Conclusion. ADSCs from RA and OA patients are similar with regard to their phenotype, percentage in IA tissue and chondrogenic potential, which is reduced after exposure to TNF. 相似文献
944.
Ross AC Leong T Avery A Castillo-Duran M Bonilla H Lebrecht D Walker UA Storer N Labbato D Khaitan A Tomanova-Soltys I McComsey GA 《HIV medicine》2012,13(2):98-106
Objectives
HIV and antiretroviral (ART) exposure in utero may have deleterious effects on the infant, but uncertainty still exists. The objective of this study was to evaluate aspects of mitochondrial DNA (mtDNA) content, mitochondrial function and oxidative stress simultaneously in placenta, umbilical cord blood and infant blood in HIV/ART‐exposed infants compared with uninfected controls.Methods
HIV‐1‐infected pregnant women and HIV‐1‐uninfected healthy pregnant controls were enrolled in the study prospectively. Placenta and umbilical cord blood were obtained at delivery and infant blood was obtained within 48 h of delivery. mtDNA content was determined for each specimen. Nuclear [subunit IV of cytochrome c‐oxidase (COX IV)]‐ and mitochondrial (COX II)‐encoded polypeptides of the oxidative phosphorylation enzyme cytochrome c‐oxidase were quantified in cord and infant blood. Placental mitochondria malondialdehyde (MDA) concentrations were measured as a marker of oxidative stress.Results
Twenty HIV‐positive/HIV‐exposed and 26 control mother–infant pairs were enrolled in the study. All HIV‐infected women and their infants received ART. Placental MDA concentration and mtDNA content in placenta and cord blood were similar between groups. The cord blood COX II:IV ratio was lower in the HIV‐positive group than in the controls, whereas the infant peripheral blood mtDNA content was higher in the HIV‐exposed infants, but the infant peripheral blood COX II:IV ratio was similar. No infant had clinical evidence of mitochondrial disease or acquired HIV infection. In multivariable regression analyses, the significant findings in cord and infant blood were both most associated with HIV/ART exposure.Conclusions
HIV‐exposed infants showed reduced umbilical cord blood mitochondrial enzyme expression with increased infant peripheral blood mitochondrial DNA levels, the latter possibly reflecting a compensatory mechanism to overcome HIV/ART‐associated mitochondrial toxicity. 相似文献945.
CTLA-4 gene is considered to be one of the strongest factors determining the predisposition to antithyroid antibody (Ab) production. The aim of the study was to evaluate the association of the polymorphism A/G of exon 1 of CTLA-4 gene and antithyroid Ab level in children with Hashimoto's thyroiditis (HT). Material and Methods: 45 children with HT (aged 14.9 ± 2, range 8.1-7.9) and 55 healthy controls (aged 14.8 ± 2.34, range 8.0-17.4) were enrolled. Controls were euthyroid and free from any autoimmune disease. CTLA-4 gene (+49)A/G polymorphism was evaluated by a single-strand conformation polymorphism method and restriction fragment-length polymorphism. Results: The frequency of GG genotype in HT children was significantly higher than in controls: 31 vs. 14.5% respectively (p < 0.04, OR = 2.65, CI = 0.99-7.06). Anti-Tg Ab titers were higher in patients homozygous for G allele than with AA genotype. The GG genotype seemed to be protective from hypothyroidism at the moment of HT diagnosis, but this observation was not statistically confirmed. Conclusions: Our study provides the evidence supporting the association between CTLA-4 gene (+49)A/G polymorphism and the susceptibility to HT in Polish children and confirms the existence of a link between (+49)A/G polymorphism and anti-Tg Ab level. 相似文献
946.
Plech T Wujec M Kosikowska U Malm A Kaproń B 《European journal of medicinal chemistry》2012,47(1):580-584
Treating infections caused by drug-resistant bacterial strains constitutes one of the most essential challenges for medicine nowadays. A range of new derivatives of 1,2,4-triazolo[3,4-b]1,3,4-thiadiazole have been synthesized and evaluated for their in?vitro antimicrobial activity. Compounds 1-8 indicated high activity towards Gram-positive bacteria, which was up to 16 times more than currently used antibiotics. To the best of our knowledge, the derivatives obtained by us are the most active among the 3-aryl-6-arylamino-1,2,4-triazolo[3,4-b]1,3,4-thiadiazoles known until now. 相似文献
947.
The latest observations indicate a continuous increase in the frequency of fungal infections, particularly in hospital patients, accompanied by changes in both the profile of the isolated strains and their drug susceptibility. The objective of this study was to evaluate the trend in the incidence of candidaemia and susceptibility of antifungal drugs in the Polish Mother's Memorial Hospital over an 11-year period. Blood samples taken from the hospitalised children were sent to the Department of Clinical Microbiology for diagnostic purposes. A total of 195 Candida strains were isolated: 47.7% Candida albicans and 52.3% non- albicans . Candida parapsilosis was isolated in 65.7% of non- albicans strains. The prevalence of Candida spp. decreased from 16.9–20.5% in the years 1996–1997 to 3.1–2.1% in the years 2005–2006. In the years 2000–2005, non- albicans strains were more prevalent. All C. albicans strains were susceptible to amphotericin B, 2.94% of non -C. albicans strains were semisusceptible to amphotericin B, 98.92% of C. albicans and 85.29% of non- albicans strains were susceptible to 5-fluorocytosine. Candida spp. strains are predominant pathogens in fungaemia in children in our hospital. Over the last few years, C. albicans have been replaced by non- albicans strains (predominantly C. parapsilosis ), which exhibit a higher level of drug resistance. The number of Candida spp. isolated from blood decreased during the 11-year study. 相似文献
948.
Slawomir Gwozdowicz Klaudia Nestorowicz Elzbieta Graczyk‐Pol Urszula Szlendak Marta Rogatko‐Koros Renata Mika‐Witkowska Daria Pawliczak Marta Zubala Agnieszka Malinowska Agnieszka Witkowska Jacek Nowak 《International journal of immunogenetics》2019,46(4):217-231
Natural killer (NK) cells make vital contributions to the immune system and the reproductive system. Notably, NK cells of donor origin can recognize and kill residual leukaemic cells and cure malignant patients in hematopoietic stem cell (HSC) transplant setting. NK cell function is regulated by KIRs that recognize cognate HLA class I molecules on target cells, depending on their amino acid residues. In review, we addressed the question of binding capacity and avidity of HLA class I molecules to different killer cell immunoglobulin‐like receptors (KIRs) depending on all interacting amino acid residues both on HLA and KIR side. We searched PubMed database and analysed available HLA:KIR crystallographic data for amino acid residues in HLA molecules, those physically involved in binding KIRs (termed here the “entire KIR interface”). Within entire KIR interface, we selected five functional sequence motifs (14–19, 66–76, 77–84, 88–92 and 142–151) and classified them according to the conservation of their amino acid sequences among 8,942 HLA class I molecules. Although some conserved amino acid motifs were shared by different groups of KIR ligands, the HLA motif combinations were exclusive for the ligand groups. In 135 common HLA class I molecules with known HLA:KIR recognition, we found 54 combinations of five motifs in each of the KIR‐binding interfaces (C1, C2, Bw4, A3/11) and conserved non‐KIR‐binding interfaces. Based on the entire KIR interface, this analysis allowed to classify 8,942 HLA class I molecules into KIR specificity groups. This functional and evolutionary classification of entire KIR interfaces provides a tool for unambiguously predicting HLA:KIR interactions for common and those HLA molecules that have not yet been functionally tested. Considering the entire KIR interface in HLA class I molecules, functional interactions of HLA and KIR can be predicted in immune responses, reproduction and allotransplantation. Further functional studies are needed on the HLA:KIR interaction variations caused by the repertoires of peptides presented by HLA molecules and KIR polymorphisms at allelic level. 相似文献
949.
950.
Alicja Tomaszek Liliana Kiczak Jacek Bania Paweł Krupa Urszula Pasławska Maciej Zacharski Adrian Janiszewski Tadeusz Stefaniak Dorota Zyśko Hossein Ardehali Ewa A. Jankowska Piotr Ponikowski 《Autonomic neuroscience : basic & clinical》2013,177(2):253-259