全文获取类型
收费全文 | 1705篇 |
免费 | 169篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 45篇 |
妇产科学 | 18篇 |
基础医学 | 202篇 |
口腔科学 | 35篇 |
临床医学 | 132篇 |
内科学 | 382篇 |
皮肤病学 | 29篇 |
神经病学 | 107篇 |
特种医学 | 43篇 |
外科学 | 189篇 |
综合类 | 143篇 |
一般理论 | 2篇 |
预防医学 | 222篇 |
眼科学 | 58篇 |
药学 | 88篇 |
中国医学 | 13篇 |
肿瘤学 | 157篇 |
出版年
2023年 | 10篇 |
2022年 | 24篇 |
2021年 | 51篇 |
2020年 | 37篇 |
2019年 | 41篇 |
2018年 | 58篇 |
2017年 | 43篇 |
2016年 | 41篇 |
2015年 | 48篇 |
2014年 | 61篇 |
2013年 | 82篇 |
2012年 | 129篇 |
2011年 | 135篇 |
2010年 | 72篇 |
2009年 | 59篇 |
2008年 | 92篇 |
2007年 | 116篇 |
2006年 | 91篇 |
2005年 | 72篇 |
2004年 | 66篇 |
2003年 | 56篇 |
2002年 | 54篇 |
2001年 | 32篇 |
2000年 | 38篇 |
1999年 | 31篇 |
1998年 | 24篇 |
1997年 | 16篇 |
1996年 | 5篇 |
1995年 | 6篇 |
1994年 | 7篇 |
1993年 | 8篇 |
1992年 | 15篇 |
1991年 | 16篇 |
1990年 | 25篇 |
1989年 | 17篇 |
1988年 | 21篇 |
1987年 | 21篇 |
1986年 | 13篇 |
1985年 | 14篇 |
1984年 | 10篇 |
1983年 | 10篇 |
1982年 | 6篇 |
1979年 | 7篇 |
1978年 | 6篇 |
1977年 | 5篇 |
1976年 | 11篇 |
1975年 | 8篇 |
1974年 | 12篇 |
1973年 | 7篇 |
1970年 | 6篇 |
排序方式: 共有1878条查询结果,搜索用时 31 毫秒
81.
Christiane?MuthEmail author Marjan?van den Akker Jeanet?W?Blom Christian?D?Mallen Justine?Rochon Fran?ois?G?Schellevis Annette?Becker Martin?Beyer Jochen?Gensichen Hanna?Kirchner Rafael?Perera Alexandra?Prados-Torres Martin?Scherer Ulrich?Thiem Hendrik?van den Bussche Paul?P?Glasziou 《BMC medicine》2014,12(1):223
Multimorbidity is a health issue mostly dealt with in primary care practice. As a result of their generalist and patient-centered approach, long-lasting relationships with patients, and responsibility for continuity and coordination of care, family physicians are particularly well placed to manage patients with multimorbidity. However, conflicts arising from the application of multiple disease oriented guidelines and the burden of diseases and treatments often make consultations challenging. To provide orientation in decision making in multimorbidity during primary care consultations, we developed guiding principles and named them after the Greek mythological figure Ariadne. For this purpose, we convened a two-day expert workshop accompanied by an international symposium in October 2012 in Frankfurt, Germany. Against the background of the current state of knowledge presented and discussed at the symposium, 19 experts from North America, Europe, and Australia identified the key issues of concern in the management of multimorbidity in primary care in panel and small group sessions and agreed upon making use of formal and informal consensus methods. The proposed preliminary principles were refined during a multistage feedback process and discussed using a case example. The sharing of realistic treatment goals by physicians and patients is at the core of the Ariadne principles. These result from i) a thorough interaction assessment of the patient’s conditions, treatments, constitution, and context; ii) the prioritization of health problems that take into account the patient’s preferences – his or her most and least desired outcomes; and iii) individualized management realizes the best options of care in diagnostics, treatment, and prevention to achieve the goals. Goal attainment is followed-up in accordance with a re-assessment in planned visits. The occurrence of new or changed conditions, such as an increase in severity, or a changed context may trigger the (re-)start of the process. Further work is needed on the implementation of the formulated principles, but they were recognized and appreciated as important by family physicians and primary care researchers.Please see related article: http://www.biomedcentral.com/1741-7015/12/222. 相似文献
82.
83.
84.
Therese Muzeniek Thejanee Perera Sahan Siriwardana Dilara Bas Fatimanur Kaplan Mizgin
ruc Beate Becker-Ziaja Inoka Perera Jagathpriya Weerasena Shiroma Handunnetti Franziska Schwarz Gayani Premawansa Sunil Premawansa Wipula Yapa Andreas Nitsche Claudia Kohl 《Viruses》2022,14(2)
Coronaviruses (CoV) are divided into the genera α-CoVs, β-CoVs, γ-CoVs and δ-CoVs. Of these, α-CoVs and β-CoVs are solely capable of causing infections in humans, resulting in mild to severe respiratory symptoms. Bats have been identified as natural reservoir hosts for CoVs belonging to these two genera. Consequently, research on bat populations, CoV prevalence in bats and genetic characterization of bat CoVs is of special interest to investigate the potential transmission risks. We present the genome sequence of a novel α-CoV strain detected in rectal swab samples of Miniopterus fuliginosus bats from a colony in the Wavul Galge cave (Koslanda, Sri Lanka). The novel strain is highly similar to Miniopterus bat coronavirus 1, an α-CoV located in the subgenus of Minunacoviruses. Phylogenetic reconstruction revealed a high identity of the novel strain to other α-CoVs derived from Miniopterus bats, while human-pathogenic α-CoV strains like HCoV-229E and HCoV-NL63 were more distantly related. Comparison with selected bat-related and human-pathogenic strains of the β-CoV genus showed low identities of ~40%. Analyses of the different genes on nucleotide and amino acid level revealed that the non-structural ORF1a/1b are more conserved among α-CoVs and β-CoVs, while there are higher variations in the structural proteins known to be important for host specificity. The novel strain was named batCoV/MinFul/2018/SriLanka and had a prevalence of 50% (66/130) in rectal swab samples and 58% (61/104) in feces samples that were collected from Miniopterus bats in Wavul Galge cave. Based on the differences between strain batCoV/MinFul/2018/SriLanka and human-pathogenic α-CoVs and β-CoVs, we conclude that there is a rather low transmission risk to humans. Further studies in the Wavul Galge cave and at other locations in Sri Lanka will give more detailed information about the prevalence of this virus. 相似文献
85.
M. Thamara P.R. Perera 《Journal of pediatric surgery》2009,44(2):e9
Embryonal rhabdomyosarcoma of the ampullary region is a very rare childhood tumor (2 reported cases), and herein we describe a child presenting with obstructive jaundice at early age owing to such tumor in the ampullary region. Successful management with multidisciplinary approach is discussed with reference to the literature. 相似文献
86.
The effect of estradiol and a combined estradiol/progestagen preparation on insulin sensitivity in healthy postmenopausal women. 总被引:2,自引:0,他引:2
A C Duncan H Lyall R N Roberts J R Petrie M J Perera S Monaghan D M Hart J M Connell M A Lumsden 《The Journal of clinical endocrinology and metabolism》1999,84(7):2402-2407
Abnormalities of carbohydrate metabolism and insulin sensitivity have been reported in estrogen deficiency. Estrogen replacement appears to result in an improvement in these parameters, although progestagens may antagonize these effects. We have examined the effects of transdermal estradiol and oral norethisterone on insulin sensitivity using the hyperinsulinemic euglycemic clamp method by performing a randomized, double blind, placebo-controlled study in 22 healthy women after a surgically induced menopause. After baseline measurements, subjects were randomized to receive either transdermal 17beta-estradiol (50 microg) or matching placebo patches for 6 weeks. The subjects were then further randomized to receive either estradiol in combination with oral norethisterone (1 mg) or a matching oral placebo preparation, crossing over after 6 weeks, with assessment of insulin sensitivity at the end of each treatment. No significant increase in insulin sensitivity was observed after 6 weeks of transdermal 17beta-estradiol treatment (95% confidence interval, -0.54, 1.86; P = 0.27). Addition of norethisterone for a further 6 weeks had no detectable effect on insulin sensitivity (95% confidence interval, -1.65, 1.10; P = 0.65). The results of this study using transdermal estradiol do not support previous reports that unopposed estrogens exert potentially beneficial effects on insulin sensitivity and suggest that the addition of an oral progestagen confers no clinically important risk or benefit. It is therefore unlikely that effects on insulin sensitivity contribute appreciably to the cardioprotective benefits attributed to hormone replacement therapy. 相似文献
87.
Coadministration of HIV vaccine vectors with vaccinia viruses expressing IL-15 but not IL-2 induces long-lasting cellular immunity 总被引:16,自引:0,他引:16 下载免费PDF全文
Oh S Berzofsky JA Burke DS Waldmann TA Perera LP 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(6):3392-3397
Vaccine efficacy is determined largely by cellular and humoral immunity as well as long-lasting immunological memory. IL-2 and IL-15 were evaluated in vaccinia vectors expressing HIV gp160 for the establishment of an effective vaccine strategy. Both IL-2 and IL-15 in the vaccinia vector induced strong and long-lasting antibody-mediated immunity as well as a short-term cytotoxic T cell response against HIV gp120. In addition, IL-15 also supported robust CD8+ T cell-mediated long-term immunity, whereas the CD8+ T cell-mediated immunity induced by IL-2 was short-lived. Moreover, we found that the cytokine milieu at the time of priming had surprisingly persistent effects on the character of the memory CD8 T cells long afterward with respect to their fate, functional activities, cytokine receptor expression, and antigen-independent proliferation. 相似文献
88.
89.
Wieslaw Jedrychowski Frederica P. Perera Jeffery Jankowski Umberto Maugeri Dorota Mrozek‐Budzyn Elzbieta Mroz Elzbieta Flak Anita Skarupa Susan Edwards Ilona Lisowska‐Miszczyk 《Pediatric allergy and immunology》2010,21(3):550-556
Jedrychowski W, Perera FP, Jankowski J, Maugeri U, Mrozek‐Budzyn D, Mroz E, Flak E, Skarupa A, Edwards S, Lisowska‐Miszczyk I. Early wheezing phenotypes and cognitive development of 3‐yr‐olds. Community‐recruited birth cohort study.Pediatr Allergy Immunol 2010: 21: 550–556.© 2009 John Wiley & Sons A/S The main purpose of the study was to answer the question whether young children without clinical diagnosis of asthma but experiencing early wheezing disorders and therefore being at high risk of developing asthma may have cognitive deficits. In the ongoing birth cohort study wheezing symptoms were recorded postpartum over two first years of age and subsequently cognitive status of children at the age of 3 yr was assessed with the Bayley Mental Development Index (MDI). In the statistical analysis a wide range of modifying and confounding factors (maternal education, gender of children, prenatal exposure to lead and environmental tobacco smoke (ETS) were considered to assess the independent effect of early wheezing phenotypes on cognitive development of children. The MDI score correlated inversely with the number of wheezing days recorded over 24 months (r = ?0.13, p = 0.007), lead cord blood concentration (r = ?0.12, p = ?0.02), number of siblings (r = ?0.17, p = 0.0006) and the number of cigarettes smoked daily by other household members at home over the pregnancy period (r = ?0.18, p = 0.0002). While the children who experienced wheezing over the first year of age showed deficit of 2 MDI scores (beta coeff. = ?2.31, 95%CI: ?4.63 to 0.02), those with persistent wheezing had the score deficit of 4 points (beta coeff. = ?4.41, 95%CI: ?8.27 to ?0.55). To our knowledge, it is the first report in the iterature showing that early wheezing is associated the cognitive deficit in a community‐recruited very young children. Observed cognitive deficit in early wheezers may be caused by RSV infections or can be related to lower lung function attributed to persistent wheezing, which reducing oxygen supply would affect rapidly developing brain. 相似文献