全文获取类型
收费全文 | 4091篇 |
免费 | 340篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 36篇 |
儿科学 | 151篇 |
妇产科学 | 84篇 |
基础医学 | 677篇 |
口腔科学 | 89篇 |
临床医学 | 383篇 |
内科学 | 895篇 |
皮肤病学 | 65篇 |
神经病学 | 448篇 |
特种医学 | 87篇 |
外科学 | 369篇 |
综合类 | 12篇 |
一般理论 | 1篇 |
预防医学 | 462篇 |
眼科学 | 95篇 |
药学 | 286篇 |
中国医学 | 5篇 |
肿瘤学 | 299篇 |
出版年
2024年 | 9篇 |
2023年 | 52篇 |
2022年 | 72篇 |
2021年 | 116篇 |
2020年 | 95篇 |
2019年 | 121篇 |
2018年 | 128篇 |
2017年 | 119篇 |
2016年 | 117篇 |
2015年 | 134篇 |
2014年 | 142篇 |
2013年 | 199篇 |
2012年 | 356篇 |
2011年 | 362篇 |
2010年 | 182篇 |
2009年 | 162篇 |
2008年 | 259篇 |
2007年 | 307篇 |
2006年 | 229篇 |
2005年 | 251篇 |
2004年 | 266篇 |
2003年 | 219篇 |
2002年 | 215篇 |
2001年 | 24篇 |
2000年 | 21篇 |
1999年 | 23篇 |
1998年 | 31篇 |
1997年 | 26篇 |
1996年 | 21篇 |
1995年 | 18篇 |
1994年 | 17篇 |
1993年 | 17篇 |
1992年 | 21篇 |
1991年 | 16篇 |
1990年 | 7篇 |
1989年 | 8篇 |
1988年 | 9篇 |
1987年 | 11篇 |
1986年 | 5篇 |
1985年 | 5篇 |
1984年 | 5篇 |
1983年 | 5篇 |
1982年 | 6篇 |
1975年 | 3篇 |
1971年 | 3篇 |
1970年 | 2篇 |
1969年 | 3篇 |
1968年 | 2篇 |
1967年 | 2篇 |
1965年 | 6篇 |
排序方式: 共有4444条查询结果,搜索用时 31 毫秒
31.
Mario Cocco Cristiana Bellan Roxane Tussiwand Davide Corti Elisabetta Traggiai Stefano Lazzi Susanna Mannucci Lucio Bronz Nazzareno Palummo Chiara Ginanneschi Piero Tosi Antonio Lanzavecchia Markus G. Manz Lorenzo Leoncini 《The American journal of pathology》2008,173(5):1369-1378
Recent studies suggest that Epstein-Barr virus (EBV) can infect naïve B cells, driving them to differentiate into resting memory B cells via the germinal center reaction. This hypothesis has been inferred from parallels with the biology of normal B cells but has never been proven experimentally. Rag2−/− γc−/− mice that were transplanted with human CD34+ cord blood cells as newborns were recently shown to develop human B, T, and dendritic cells, constituting lymphoid organs in situ. Here we used this model to better define the strategy of EBV infection of human B cells in vivo and to compare this model system with different conditions of EBV infection in humans. Our results support the model of EBV persistence in vivo in cases that were characterized by follicular hyperplasia and a relatively normal CD4+ and CD8+ T-cell distribution. Intriguingly, in cases that were characterized by nodular and diffuse proliferation with a preponderance of CD8+ T cells, similar to infectious mononucleosis, EBV still infects naïve B cells but also induces clonal expansion and ongoing somatic mutations without germinal center reactions. Our results reveal different strategies of EBV infection in B cells that possibly result from variations in the host immune response. Future experiments might allow understanding of the mechanisms responsible for persistent EBV infection and provide targets for more highly tailored therapeutic interventions. 相似文献
32.
Mauro Congia Fulvia Frau Rosanna Lampis Rita Frau Roberto Mele Francesco Cucca Francesco Muntoni Susanna Porcu Francesca Boi Licinio Contu Giorgio La Nasa Marina Mulargia Mario Pirastu Antonio Cao Stefano De Virgillis 《Tissue antigens》1992,39(2):78-83
This study characterizes by serological and molecular methods the HLA class I and class II alleles in a group of celiac disease children, their parents and a control group of Sardinian descent. We found the DR3-DQw2 haplotype in all patients which was, in almost all cases (84%), associated with the HLA-A30, B18, DR3, DRw52, DQw2 extended haplotype named "Sardinian haplotype" because of its frequency (12-15%) in this Caucasian population. This is the first time that this DQw2-linked haplotype has been reported with such a high frequency in CD. However, no different distribution of "Sardinian haplotype" was found comparing CD patients with 91 haplotyped DQw2-positive controls. This finding indicates that the DQw2 antigen in Sardinians is almost always associated with the A30, B18, DR3, DRw52, DQw2 extended haplotype. The DQA1 and DQB1 second exon sequence analysis of the B18,DR3 and B8,DR3 haplotypes showed the DQA1*0501 and DQB1*0201 alleles which shared the already published sequences. DPB1 subtyping showed the DPB1*0301 allele more frequently (p less than 0.005) in CD patients but this difference was no longer significant when patients and controls, both heterozygous for the DR3-DQw2 haplotype, were compared. We suggest that the divergent HLA extended haplotypes and DP allele associated with CD, described in different Caucasian populations, can be explained by the particular DQw2 linkage disequilibrium in each population. 相似文献
33.
Granulocyte superoxide production by different stimuli was studied in 14 patients suffering from rheumatoid arthritis, and in four cases defective (O
2
–
generation was shown. The effect of two chemically related drugs, such as indomethacin and oxamethacin, was also evaluated, since we have previously investigated the action of antiinflammatory agents on cell locomotion. Indomethacin did not affect O
2
–
production, whereas oxamethacin reduced significantly superoxide generation in PMNs from all subjects tested. Moreover, the extent of the effect was dependent on the stimulant used, being larger when the activation of O
2
–
generating system was induced by opsonized zymosan. 相似文献
34.
Alicia Aguilar-Martínez Marina Bosque-Prous Helena Gonzlez-Casals Ester Colillas-Malet Susanna Puigcorb Laura Esquius Albert Espelt 《Nutrients》2021,13(5)
Adolescence is a critical period in the consolidation of healthy lifestyles that can last into adulthood. To analyze changes in food consumption and eating behaviors in high-school adolescents during the first confinement, a cross-sectional study was conducted at the end of confinement in Spain. Changes in the frequency or quantity of consumption of different types of food and food-related behaviors were analyzed. Socioeconomic and health-related variables were also considered. To determine whether dietary changes were related to socioeconomic position (SEP), Poisson regression models with robust variance were estimated. Overall, there were some changes towards a healthier diet such as an increase in fruit consumption (38.9%) and a decrease in the consumption of soft drinks (49.8%), sweets and pastries (39.3%), and convenience foods (49.2%). Some changes, however, were related to less healthy behaviors, such as a more irregular pattern of meal distribution (39.9%) or an increase in snacking between meals (56.4%). Changes towards less healthy eating were also related to students’ SEP. The risk of worsening the diet was found to be 21% higher in adolescents from a more disadvantaged SEP. Future public policies could be adapted to avoid increasing nutritional and health inequalities. 相似文献
35.
36.
Lorente Nicolas Sherriff Nigel Panochenko Oksana Marcus Ulrich Dutarte Maria Kuske Matthias Aussó Susanna Huber Jörg Krone Michael Schink Susanne Barbara Cawley Caoimhe Casabona Jordi Folch Cinta 《Journal of community health》2021,46(3):545-556
Journal of Community Health - Little is known about Community Health Workers (CHWs) who work in non-clinical settings to provide sexual health support around HIV, viral hepatitis, and other... 相似文献
37.
V Susanna A Loffreda M G Matera R Servodio A Filippelli A Santagata C Montanaro N Carapella E Marmo 《International journal of tissue reactions》1990,12(1):59-65
We have investigated the effect of inhaled adenosine on bronchomotor tone in 16 healthy and 24 allergic and non-allergic bronchopathic subjects. We determined the inhaled adenosine dose-response curves after no treatment and after treatment with aminophylline (240 mg in 10 min), reproterol (90 mcg in 2 min) and salbutamol (100 mcg in 2 min) administered intravenously 15 min before adenosine and reproterol (500 mcg) and salbutamol (200 mcg) administered by inhalation from a metered aerosol 30 min before adenosine on separate days. Without prior treatment, inhaled adenosine caused bronchoconstriction in both groups of subjects (normal, and atopic and non-atopic asthmatic ones), but the peripheral airways revealed only a moderate change in normal subjects. Aminophylline caused a greater inhibition of adenosine bronchoconstriction than did reproterol. These results suggest that inhaled adenosine bronchoconstriction involved purinergic transmission and that it is mediated via a P1/Ri (A-1/R1) receptor. Aminophylline is a potent antagonist at purinoceptor level. Reproterol inhibits bronchoconstriction by a mechanism independent of its effect on beta-adrenergic receptors. Because salbutamol, i.e. a beta 2-agonist bronchodilator, did not inhibit adenosine-induced bronchoconstriction (or very nearly so), our results support the view that reproterol antagonizes P1/Ri (A1/R1) tracheobronchial receptors. 相似文献
38.
Susanna Jernelöv Erik Forsell Henrietta Westman Ylva Eriksson Dufva Nils Lindefors Viktor Kaldo Martin Kraepelien 《Journal of sleep research》2023,32(2):e13759
Cognitive behavioural therapy for insomnia is efficacious and recommended for insomnia, but availability is scarce. Cognitive behavioural therapy for insomnia self-help interventions could increase availability, especially if unguided. Optimizing cognitive behavioural therapy for insomnia methods and system user-friendliness, we developed a short, digital, self-help programme—FastAsleep—based on the behavioural components of sleep restriction and stimulus control. This study investigated its feasibility and preliminary effects. Thirty media-recruited participants with moderate to severe insomnia were assessed via telephone before using FastAsleep for 4 weeks, and were interviewed afterwards. Self-ratings with web questionnaires were conducted at screening, pre-, mid- and post-treatment, and at 3-month follow-up. Primary outcomes were feasibility (credibility, adherence, system user-friendliness and adverse effects), and secondary outcomes were changes in symptom severity (insomnia, depression and anxiety). Adherence was generally high, participants' feasibility ratings were favourable, and adverse effects matched previously reported levels for cognitive behavioural therapy for insomnia. Symptoms of insomnia decreased after the treatment period (Hedge's g = 1.79, 95% confidence interval = 1.20–2.39), as did symptoms of depression and anxiety. FastAsleep can be considered feasible and promising for alleviating insomnia symptoms among patients fit for self-care. Future controlled trials are needed to establish the efficacy of FastAsleep and its suitability in a stepped care model. 相似文献
39.
Septo-optic dysplasia and growth hormone deficiency: accelerated pubertal maturation during GH therapy 总被引:1,自引:0,他引:1
Susanna Freude H Frisch Daniela Wimberger Edith Schober Gabriele Häusler F Waldhauser F Aichner 《Acta paediatrica (Oslo, Norway : 1992)》1992,81(8):641-645
We report four patients (three male, one female) with septo-optic dysplasia and growth hormone deficiency. All had GH therapy for a period of four to eight years until reaching final height. In all four cases bone maturation during puberty was accelerated (1.4 to 1.9 "years"/year), resulting in a final height which was clearly below the predicted height. The progress of pubertal stages was very short in all patients. In three patients TSH and prolactin release after TRH stimulation were increased. These data support a hypothalamic original of the endocrine disorder. Insufficient GH release, even after repeated GHRH stimulation, is in contrast to this assumption. In one case there was a late manifestation of neurohormonal diabetes insipidus, which indicates the possibility of later disease progression. MR imaging of the brain demonstrated variable malformation of the septum pellucidum, chiasma and nervus opticus or the pituitary gland, respectively. 相似文献
40.
Susanna Hegewisch-Becker Katharina Braun Markus Otte Aneta Corovic Djordje Atanackovic Axel Nierhaus Dieter K Hossfeld Klaus Pantel 《Clinical cancer research》2003,9(6):2079-2084
PURPOSE: Combining heat with antineoplastic drugs has produced evidence of antitumor synergism. An increasing number of trials are investigating whole body hyperthermia (WBH) in combination with chemotherapy in patients with advanced malignancies. Here we investigated whether the hyperdynamic state of the circulation as a consequence of WBH may stimulate dissemination of malignant cells. EXPERIMENTAL DESIGN: WBH in combination with chemotherapy was administered by a radiant heat device to 20 consecutive patients with advanced epithelial malignancies. One WBH session lasted for approximately 4 h (90 min heating time, 60 min plateau at 41.8 degrees C, and 60-80 min cooling). Peripheral blood was drawn before WBH treatment (baseline), at the end of the plateau (1 h), and 24 h and 48 h thereafter. After removal of leukocytes using anti-CD45 magnetic beads, circulating tumor cells were detected immunocytochemically using the monoclonal antibody A45-B/B3, which binds to a common epitope present on various cytokeratins. RESULTS: The method used to detect tumor cells in the peripheral blood proved to be specific and very sensitive (detection limit 1 tumor cell per 1.7 x 10(5) peripheral blood mononuclear cell). Before WBH, 6 of 20 patients had cyto-keratin-positive cells in their blood. A treatment-induced increase in the number of circulating tumor cells became statistically significant at 24 h after WBH (P = 0.043) and was detected in a total of 9 patients, 5 of whom had no detectable malignant cells at baseline. There was no evidence of a correlation between an increase in the number of circulating tumor cells and increased metastasis frequency. CONCLUSIONS: Our findings suggest that WBH might induce a temporary release of tumor cells into the circulation, but this spread appears to be clinically not significant in patients with advanced malignancies. 相似文献