全文获取类型
收费全文 | 1211篇 |
免费 | 65篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 70篇 |
妇产科学 | 20篇 |
基础医学 | 105篇 |
口腔科学 | 23篇 |
临床医学 | 139篇 |
内科学 | 356篇 |
皮肤病学 | 20篇 |
神经病学 | 89篇 |
特种医学 | 16篇 |
外科学 | 138篇 |
综合类 | 5篇 |
预防医学 | 114篇 |
眼科学 | 13篇 |
药学 | 102篇 |
中国医学 | 8篇 |
肿瘤学 | 66篇 |
出版年
2024年 | 1篇 |
2023年 | 10篇 |
2022年 | 24篇 |
2021年 | 62篇 |
2020年 | 29篇 |
2019年 | 51篇 |
2018年 | 59篇 |
2017年 | 36篇 |
2016年 | 40篇 |
2015年 | 37篇 |
2014年 | 49篇 |
2013年 | 70篇 |
2012年 | 102篇 |
2011年 | 111篇 |
2010年 | 64篇 |
2009年 | 54篇 |
2008年 | 85篇 |
2007年 | 96篇 |
2006年 | 84篇 |
2005年 | 52篇 |
2004年 | 54篇 |
2003年 | 39篇 |
2002年 | 60篇 |
2001年 | 2篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1998年 | 6篇 |
1997年 | 1篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1985年 | 1篇 |
排序方式: 共有1289条查询结果,搜索用时 0 毫秒
1.
2.
Nakopoulou L Tsirmpa I Giannopoulou I Trafalis D Katsarou S Davaris P 《Cancer Genetics and Cytogenetics》2002,134(2):127-132
Breast carcinoma is a genetically and phenotypically heterogeneous disease and is frequently associated with nonrandom chromosomal alterations. The aim of this study was to investigate the numerical aberrations of chromosome 20 in breast cancer. The observed chromosome-specific numerical abnormalities were evaluated along with the established clinicopathological parameters, the immunohistochemical expression of ER, PR, p53, c-erbB-2, Ki-67 and patients' survival. Nonisotopic in situ hybridization was applied to interphase cell nuclei on paraffin embedded tissue sections. Polysomy of chromosome 20 was the prevalent alteration in 45 of 50 (90%), monosomy in 2 of 50 (4%) and disomy in 3 of 50 (6%) cases. Invasive ductal carcinomas displayed a higher percentage of polysomy than lobular ones. A statistical significant association was demonstrated between Ki-67 immunohistochemical expression and polysomy of chromosome 20. Disomy was inversely correlated with Ki-67, while monosomy was suggestively associated with PR positive expression. Among the patients, those with the highest levels of polysomy showed the worst survival. In conclusion, the gain of chromosome 20 is the prevalent aberration in patients with breast carcinomas and may be useful prognostic marker in breast cancer. 相似文献
3.
Ioanna Dori John G. Parnavelas 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1996,110(3):347-359
The excitatory amino acids l-glutamate and l-aspartate are believed to be utilized as neurotransmitters by the pyramidal neurons in the mammalian cerebral cortex. These cells can be recognized early in development, while glutamate might play an important part in the maturation and plasticity of the cortex. Here, we used light and electron microscopic immunocytochemistry to study the time of appearance and maturation of glutamate and aspartate in neurons of the rat visual cortex. Glutamate- and aspartate-immunoreactive cells were first detected in deep cortical layers at postnatal day 3. During the next 3 weeks, labelled neurons were observed progressively in more superficial layers, but did not demonstrate their adult pattern of distribution until postnatal week 4. Electron microscopic analysis showed that glutamate- and aspartate-labelled neurons gradually develop their cytological and synaptic features during the first 4 postnatal weeks, with this process of differentiation originating in the deep cortical layers and progressively extending to the superficial layers. These findings suggest that cortical pyramidal neurons begin to express detectable levels of transmitter glutamate and/or aspartate after they have completed their migration. Their neurochemical differentiation follows an inside-out pattern similar to the pattern described for the genesis and morphological differentiation of this population of cortical neurons. 相似文献
4.
Nicolaos C. Tassopoulos Krzysztof Krawczynski Angelos Hatzakis Antigoni Katsoulidou Ioanna Delladetsima Maria G. Koutelou Dimitrios Trichopoulos 《Journal of medical virology》1994,42(2):124-128
The aim of this study was to determine the frequency of hepatitis E virus (HEV) infection in a population of Greek adults with community-acquired (sporadic) non-A, non-B hepatitis found to be seronegative for antibodies to hepatitis C virus (anti-HCV). All patients admitted to the Liver Unit of Western Attica General Hospital and diagnosed as having acute community-acquired non-A, non-B hepatitis between February, 1986, and May, 1990, were enrolled in follow up studies (n = 66). Nineteen patients with HCV infection and 11 patients with acute non-A, non-B, non-C hepatitis that progressed to chronicity were excluded. Convalescent sera were tested for antibody to HEV (anti-HEV) by a fluorescent antibody blocking assay in 33 of 36 eligible patients. One of the 33 (3%) patients was found to be positive for anti-HEV. Anti-HEV testing of all 20 available serum specimens from this patient showed evidence of anti-HEV seroconversion at the fourth week after the onset of hepatitis. The patient had not travelled abroad or within Greece or had not had apparent contact with people from foreign countries for the previous 3 months. These data show that HEV infection is not a major cause of community-acquired non-A, non-B hepatitis in Greece. However, the reported case of HEV hepatitis suggests that HEV may retain a low endemicity in Greece. More extensive seroprevalence studies are needed for an accurate estimation of the extent of HEV infection in the southeastern European countries. © 1994 Wiiey-Liss, Inc. 相似文献
5.
Ioanna K. Bolia 《Arthroscopy》2021,37(1):95-97
The management of the capsule during hip arthroscopy for femoroacetabular impingement syndrome has been in the spotlight during the last decade. Although there is robust biomechanical evidence that preserving the anatomic integrity of the iliofemoral ligament is important for the stability of the hip joint, the effect of capsular management on patient outcomes is often debated in clinical studies. Mid-term and long-term follow-up studies have shown that capsular closure is associated with decreased risk of hip arthroscopy failure, but no difference in patient outcomes based on capsular management has been found by some case series studies. What is driving the controversy in the literature? It seems to stem from the variation in surgical techniques used to perform hip capsulotomy or capsular repair, worldwide. Given that improvement in patient outcomes must be prioritized, it is time to use the existing knowledge appropriately to establish evidence-based guidelines for the management of hip capsule during hip arthroscopy. 相似文献
6.
7.
Elliott Joshua Bodinier Barbara Whitaker Matthew Delpierre Cyrille Vermeulen Roel Tzoulaki Ioanna Elliott Paul Chadeau-Hyam Marc 《European journal of epidemiology》2021,36(3):299-309
European Journal of Epidemiology - Most studies of severe/fatal COVID-19 risk have used routine/hospitalisation data without detailed pre-morbid characterisation. Using the community-based UK... 相似文献
8.
Zoi Tsimtsiou Ioanna Tsiligianni Anastasia Papaioannou Dimitrios Gougourelas Konstantinos Kolokas Vasileios Gkizlis Emmanuil Chatzimanolis Philippe-Richard J. Domeyer 《Health & social care in the community》2021,29(3):818-828
Despite the unequivocal value of vaccination in reducing the global burden of infectious diseases, the anti-vaccination movement thrives. The vast majority of the existing validated tools explore attitudes regarding vaccination in children. The aim of our study was to develop and validate a scale assessing attitudes towards adult immunisation. This national cross-sectional study included adult healthcare users who visited 23 Greek Primary Healthcare Units. The development of the scale was the result of literature review, semi-structured interviews and pilot testing of its preliminary versions. The initial version contained 15 items measuring respondents’ attitudes on a 6-point Likert scale. The sample was randomly split into two halves. Exploratory factor analysis, performed in the first sample, was used for the creation of multi-item scales; confirmatory factor analysis was used in the second sample to assess goodness of fit. Moreover, concurrent validity, internal consistency reliability, test–retest reliability and ceiling and floor effects were explored. The total sample consisted of 1,571 individuals. Overall ‘Cronbach's alpha’ (0.821) indicated good internal consistency. The initial exploratory factor analysis resulted in a three-factor model. The subsequent confirmatory factor analysis indicated that an 11-item version of the scale provided the best fit of the model to the data (RMSEA = 0.050, SRMR = 0.053, TLI = 0.937, CFI = 0.955, AIC = 24,999.949). All subscales (‘value of adult vaccination’, ‘safety concerns’ and ‘perceived barriers’) demonstrated strong concurrent associations with participants’ attitudes and behaviour regarding vaccination (p < .001). No ceiling or floor effects were noted for any of the subscales (0.13%, 2.61% and 0.51%; 0.13%, 0.57% and 0.45% respectively). The 11-item ATAVAC scale proved to be a reliable and valid tool, suitable for assessing attitudes towards adult vaccination. 相似文献
9.
Nikolaos Athanasiou Katerina Baou Eleni Papandreou Georgia Varsou Anastasia Amfilochiou Elisavet Kontou Athanasia Pataka Konstantinos Porpodis Ioanna Tsiouprou Evangelos Kaimakamis Serafeim-Chrysovalantis Kotoulas Evgenia Katsibourlia Christina Alexopoulou Izolde Bouloukaki Meropi Panagiotarakou Aspasia Dermitzaki Nikolaos Charokopos Kyriakh Pagdatoglou Kallirroi Lamprou Sofia Pouriki Foteini Chatzivasiloglou Zoi Nouvaki Alexandra Tsirogianni Ioannis Kalomenidis Paraskevi Katsaounou Emmanouil Vagiakis 《Journal of sleep research》2023,32(1):e13656
Growing evidence suggests that sleep could affect the immunological response after vaccination. The aim of this prospective study was to investigate possible associations between regular sleep disruption and immunity response after vaccination against coronavirus disease 2019 (COVID-19). In total, 592 healthcare workers, with no previous history of COVID-19, from eight major Greek hospitals were enrolled in this study. All subjects underwent two Pfizer–BioNTech messenger ribonucleic acid (mRNA) COVID-19 vaccine BNT162b2 inoculations with an interval of 21 days between the doses. Furthermore, a questionnaire was completed 2 days after each vaccination and clinical characteristics, demographics, sleep duration, and habits were recorded. Blood samples were collected and anti-spike immunoglobulin G antibodies were measured at 20 ± 1 days after the first dose and 21 ± 2 days after the second dose. A total of 544 subjects (30% males), with median (interquartile range [IQR]) age of 46 (38–54) years and body mass index of 24·84 (22.6–28.51) kg/m2 were eligible for the study. The median (IQR) habitual duration of sleep was 6 (6–7) h/night. In all, 283 participants (52%) had a short daytime nap. In 214 (39.3%) participants the Pittsburgh Sleep Quality Index score was >5, with a higher percentage in women (74·3%, p < 0.05). Antibody levels were associated with age (r = −0.178, p < 0.001), poor sleep quality (r = −0.094, p < 0.05), insomnia (r = −0.098, p < 0.05), and nap frequency per week (r = −0.098, p < 0.05), but after adjusting for confounders, only insomnia, gender, and age were independent determinants of antibody levels. It is important to emphasise that insomnia is associated with lower antibody levels against COVID-19 after vaccination. 相似文献
10.