全文获取类型
收费全文 | 2880篇 |
免费 | 130篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 113篇 |
妇产科学 | 67篇 |
基础医学 | 510篇 |
口腔科学 | 22篇 |
临床医学 | 239篇 |
内科学 | 580篇 |
皮肤病学 | 29篇 |
神经病学 | 225篇 |
特种医学 | 206篇 |
外科学 | 489篇 |
综合类 | 24篇 |
一般理论 | 2篇 |
预防医学 | 120篇 |
眼科学 | 20篇 |
药学 | 200篇 |
中国医学 | 6篇 |
肿瘤学 | 161篇 |
出版年
2023年 | 13篇 |
2022年 | 30篇 |
2021年 | 61篇 |
2020年 | 33篇 |
2019年 | 31篇 |
2018年 | 50篇 |
2017年 | 44篇 |
2016年 | 61篇 |
2015年 | 69篇 |
2014年 | 101篇 |
2013年 | 116篇 |
2012年 | 161篇 |
2011年 | 184篇 |
2010年 | 108篇 |
2009年 | 121篇 |
2008年 | 184篇 |
2007年 | 218篇 |
2006年 | 205篇 |
2005年 | 190篇 |
2004年 | 167篇 |
2003年 | 183篇 |
2002年 | 192篇 |
2001年 | 52篇 |
2000年 | 33篇 |
1999年 | 33篇 |
1998年 | 34篇 |
1997年 | 37篇 |
1996年 | 43篇 |
1995年 | 27篇 |
1994年 | 16篇 |
1993年 | 17篇 |
1992年 | 12篇 |
1991年 | 10篇 |
1990年 | 14篇 |
1989年 | 11篇 |
1988年 | 11篇 |
1987年 | 11篇 |
1986年 | 9篇 |
1985年 | 12篇 |
1983年 | 7篇 |
1982年 | 10篇 |
1981年 | 8篇 |
1978年 | 6篇 |
1976年 | 5篇 |
1975年 | 4篇 |
1973年 | 4篇 |
1972年 | 8篇 |
1971年 | 7篇 |
1970年 | 8篇 |
1939年 | 5篇 |
排序方式: 共有3021条查询结果,搜索用时 34 毫秒
81.
82.
Olga Moser Martin Zimmermann Ulrike Meyer Wolfram Klapper Ilske Oschlies Martin Schrappe Andishe Attarbaschi Georg Mann Felix Niggli Claudia Spix Udo Kontny Thomas Klingebiel Alfred Reiter Birgit Burkhardt Wilhelm Woessmann 《Haematologica》2021,106(5):1390
Second malignant neoplasms (SMN) pose a concern for survivors of childhood cancer. We evaluated incidence, type and risk factors for SMN in patients included in Berlin-Frankfurt-Muenster protocols for childhood non-Hodgkin lymphoma.3,590 patients <15 years of age at diagnosis, registered between 01/1981 and 06/2010, were analyzed. SMN were reported by the treating institutions and the German Childhood Cancer Registry. After a median follow-up of 9.4 years (quartile [Q] range, Q1 6.7 and Q3 12.1) 95 SMN were registered (26 carcinomas including nine basal cell carcinomas, 21 acute myeloid leukemias/myelodysplastic syndromes, 20 lymphoid malignancies, 12 central nervous system [CNS]-tumors, and 16 others). Cumulative incidence at 20 years was 5.7±0.7%, standard incidence ratio, excluding basal cell carcinomas, was 19.8 (95% Confidence Interval [CI]: 14.5-26.5). Median time from initial diagnosis to second malignancy was 8.7 years (range, 0.2-30.3 years). Acute-lymphoblasticleukemia- type therapy, cumulative anthracycline dose, and cranial radiotherapy for brain tumor-development were significant risk factors in univariate analysis only. In multivariate analysis including risk factors significant in univariate analysis, female sex (hazard ratio [HR] 1.87, 95% CI: 1.23-2.86, P=0.004), CNS-involvement (HR 2.24, 95% CI: 1.03-4.88, P=0.042), lymphoblastic lymphoma (HR 2.60, 95% CI: 1.69-3.97, P<0.001), and cancer-predisposing condition (HR 11.2, 95% CI: 5.52-22.75, P<0.001) retained an independent risk. Carcinomas were the most frequent SMN after non-Hodgkin lymphoma in childhood followed by acute myeloid leukemia and lymphoid malignancies. Female sex, lymphoblastic lymphoma, CNS-involvement, or/and known cancer-predisposing condition were risk factors for SMN-development. Our findings set the basis for individualized long-term follow-up and risk assessment of new therapies. 相似文献
83.
84.
The recent technical advances in magnetic resonance imaging (MRI) and multislice computed tomography (MSCT) have led to a routine use of both methods in clinical cardiology. MRI is established for the diagnosis of complex congenital heart disease, aortic and pericardial disease as well as cardiac tumours. New indications include the diagnosis of myocardial infarction and inflammatory heart disease as well as myocardial perfusion measurements. CT is used for the diagnosis of coronary calcification for risk stratification. Moreover, stenoses of the coronary arteries and bypass grafts can be depicted using contrast enhanced multi-slice CT in selected patients. Training of cardiologists in the field of MRI has been defined by the Deutsche Arztetag in 2003 and demands 24 months of full-time training. At least 12 months must be spent in a department of radiology. Alternatively, the approach of the Landes?rztekammer Baden-Württemberg is presented. 相似文献
85.
Breitmeier D Becker N Weilbach C Albrecht K Scheinichen D Panning B Schneider U Jüttner B 《Alcoholism, clinical and experimental research》2008,32(10):1708-1713
Background: Polymorphonuclear, neutrophil granulocytes (PMN) play a major role in the control of infections, and people who abuse alcohol are susceptible to infections. Resistance against infections ensues intracellularly following initial phagocytosis of microorganisms with the oxygen‐dependent respiratory burst, the key enzyme of which is the respiratory burst oxidase, whereby oxygen radicals are produced for microbial destruction. To date there is insufficient information available in connection with the process of impaired defence against infection in patients suffering from alcohol dependence. Therefore, our investigation was carried out to determine the influence of alcohol exposition on the formation of oxygen radicals and the respiratory burst. Methods: 4.5 ml of whole blood was taken from 10 healthy adults and 10 patients suffering from alcohol dependence. An additional 3.5 ml of whole blood was taken from the alcoholic patients for determination of the blood alcohol concentration. The respiratory burst of PMN was tested using the Four‐Colour‐Continuous Flow Cytometer. Each experimental procedure consisted of 4 test samples [negative controls, Escherichia coli, FMLP‐supplement (N‐formyl‐l‐methionyl‐l‐leucyl‐l‐phenylalanin), PMA‐supplement (phorbol‐12‐myristate‐13‐acetate)]. Differing concentrations of ethanol were also introduced to each of the tests performed (0.20 to 4.00 g/l). Results: Ethanol revealed a marked decrease of burst activity in those patients suffering from alcoholism with increased alcohol concentration. A dependence between the burst activity and the ethanol concentration was seen to be statistically significant. This effect was only evident after stimulation with E. coli and FMLP in those patients with alcohol dependence. Conclusion: The results presented in this study show an impairment in the function of PMN in those patients addicted to alcohol due to the decrease in burst activity. In view of the results of the different stimuli, the second‐messenger effects were not evident. A clarification of this phenomenon could well be assumed as an allosteric receptor effect on the burst oxidase, namely, a direct effect on the phagocytosis interaction between circulating granulocytes and causative organisms. 相似文献
86.
Orietta D'Orlando Fang Zhao Brigitte Kasper Zane Orinska Jürgen Müller Irm Hermans‐Borgmeyer Gillian M. Griffiths Udo Zur Stadt Silvia Bulfone‐Paus 《European journal of immunology》2013,43(1):194-208
Syntaxin 11 (STX11) controls vesicular trafficking and is a key player in exocytosis. Since Stx11 mutations are causally associated with a familial hemophagocytic lymphohistio‐cytosis, we wanted to clarify whether STX11 is functionally important for key immune cell populations. This was studied in primary cells obtained from newly generated Stx11?/? mice. Our data revealed that STX11 is not only widely expressed in different immune cells, but also induced upon LPS or IFN‐γ treatment. However, Stx11 deficiency does not affect macrophage phagocytic function and cytokine secretion, mast cell activation, or antigen presentation by DCs. Instead, STX11 selectively controls lymphocyte cytotoxicity in NK and activated CD8+ T cells and degranulation in neutrophils. Stx11?/? NK cells and CTLs show impaired degranulation, despite a comparable activation, maturation and expression of the complex‐forming partners MUNC18–2 and VTI1B. In addition, Stx11?/? CTLs and NK cells produce abnormal levels of IFN‐γ. Since functional reconstitution rescues the defective phenotype of Stx11?/? CTLs, we suggest a direct, specific and key role of STX11 in controlling lymphocyte cytotoxicity, cytokine production and secretion. Finally, we show that these mice are a very useful tool for dissecting the role of STX11 in vesicular trafficking and secretion. 相似文献
87.
Satyan S. Kalkunte Stefan Neubeck Wendy E. Norris Shi-Bin Cheng Stefan Kostadinov Dang Vu Hoang Aftab Ahmed Ferdinand von Eggeling Zahir Shaikh James Padbury Goran Berg Anders Olofsson Udo R. Markert Surendra Sharma 《The American journal of pathology》2013,183(5):1425-1436
Preeclampsia is a major pregnancy complication with potential short- and long-term consequences for both mother and fetus. Understanding its pathogenesis and causative biomarkers is likely to yield insights for prediction and treatment. Herein, we provide evidence that transthyretin, a transporter of thyroxine and retinol, is aggregated in preeclampsia and is present at reduced levels in sera of preeclamptic women, as detected by proteomic screen. We demonstrate that transthyretin aggregates form deposits in preeclampsia placental tissue and cause apoptosis. By using in vitro approaches and a humanized mouse model, we provide evidence for a causal link between dysregulated transthyretin and preeclampsia. Native transthyretin inhibits all preeclampsia-like features in the humanized mouse model, including new-onset proteinuria, increased blood pressure, glomerular endotheliosis, and production of anti-angiogenic factors. Our findings suggest that a focus on transthyretin structure and function is a novel strategy to understand and combat preeclampsia.Preeclampsia occurs in 5% to 8% of pregnancies worldwide and is a major cause of fetal and maternal morbidity and mortality.1–3 It is a heterogeneous disease with varied presentations from mild self-limited hypertension and proteinuria to severe forms with significant end-organ dysfunction and HELLP syndrome (hemolysis, elevated liver enzymes, and low platelets).3 Although the cause of preeclampsia and its appropriate treatment remain elusive, this syndrome has been proposed to reflect at least two stages of complications during pregnancy. These begin with preclinical manifestations at the maternal-fetal interface, followed by systemic clinical symptoms.1,2 Hypertension, proteinuria, and edema, with a variable degree of fetal growth restriction, are the cardinal features of preeclampsia.3 Because the placenta is the nutritional and immunological gateway to normal fetal development and pregnancy outcome, placenta-related events are believed to be central to the pathogenesis of this disease. Evidence exists for the release of disease-initiating molecules into maternal circulation that triggers the clinical symptoms.1,4 Placental and systemic anomalies reflected by circulating placental debris, inflammation, impaired remodeling of spiral arteries, placental hypoxia/ischemia, excess production of anti-angiogenic factors [soluble fms-like tyrosine kinase-1 (sFlt-1)], and soluble endoglin (sEng), and angiotensin receptor autoantibodies have all emerged as contributors to the pathophysiological characteristics of preeclampsia.2,4–14Preeclampsia has remained enigmatic because of lack of well-defined etiology and animal models. Although normal mice do not develop preeclampsia spontaneously, mouse models have been judged to be particularly useful to uterine diseases and pregnancy complications because many similarities in female reproduction and placentation have been identified between the two species.15 Moreover, their tractable genetics provide an effective way to probe mechanisms more deeply than many other species.15–17 We recently showed that sera from preeclamptic women could function as a source of novel causative factors that induced hypertension, proteinuria, and kidney pathological characteristics, as well as intrauterine growth restriction (IUGR), in IL-10−/− mice in a pregnancy-specific manner.18 IL-10 functions as a potent vascular and anti-inflammatory cytokine and has been shown to be present at significantly reduced levels in preeclampsia placental tissue.19,20 Preeclampsia serum (PES) was found to disrupt endovascular cross talk between trophoblasts and endothelial cells and to induce placental hypoxia and excess production of sFlt-1 and sEng,18 soluble factors known to precipitate maternal symptoms.21,22 These results from our serum-based humanized mouse model suggest that the pathophysiological characteristics of preeclampsia are more complex than previously thought and are likely to involve interactions and dysregulation of multiple factors. By using serum proteomic screening by surface-enhanced laser-desorption ionization-time-of-flight (SELDI-TOF), our results suggest that PES contains a reduced abundance of transthyretin, a plasma transport protein for the thyroid hormone, thyroxine, and retinol-binding protein.23 More important, transthyretin has been widely studied for its role in amyloid diseases associated with protein misfolding and aggregation, resulting in deposits of toxic, fibrillar aggregates in specific organs.24–26 Dysregulated or reduced transthyretin has also been implicated in Alzheimer disease, and overexpression of a wild-type human transthyretin transgene has been shown to ameliorate the disease in the transgenic murine model of human Alzheimer disease.27,28 Transthyretin in its native form assumes a homotetrameric quaternary configuration (approximately 14 kDa per monomer). Post-translational modifications of the monomer result in detection of several isoforms.29 Circulating transthyretin is also a validated marker of malnutrition and has a putative role in oocyte maturation and inflammation.30–32 Although the presence of transthyretin during implantation in mice and in the placenta and trophoblasts in humans has been reported,33,34 its functional role in normal pregnancy or adverse pregnancy outcomes has not been recognized. We hypothesize that transthyretin in preeclampsia is structurally and functionally dysregulated and contributes to the onset of this serious pregnancy complication. Herein, we present complementary in vitro and in vivo approaches, which show that endogenously altered transthyretin is a preeclampsia-causing agent and that native transthyretin has the ability to block the onset of preeclampsia-like features. 相似文献
88.
Stefanie J.G. Veenhuis MD Nienke J.H. van Os MD PhD Anjo J.W.M. Janssen PhD Marjo H.J.C. van Gerven MSc Karlien L.M. Coene PhD Udo. F.H. Engelke PhD Ron A. Wevers PhD Gerjen H. Tinnevelt PhD Rob ter Heine PhD Bart P.C. van de Warrenburg MD PhD Corry M.R. Weemaes MD PhD Nel Roeleveld PhD Michèl A.A.P. Willemsen MD PhD 《Movement disorders》2021,36(12):2951-2957
89.
Udo Rüb Franziska Hoche Ewout R. Brunt Helmut Heinsen Kay Seidel Domenico Del Turco Henry L. Paulson Jürgen Bohl Charlotte von Gall Jean‐Paul Vonsattel Horst‐Werner Korf Wilfred F. den Dunnen 《Brain pathology (Zurich, Switzerland)》2013,23(2):165-177
Huntington's disease (HD) is a polyglutamine disease and characterized neuropathologically by degeneration of the striatum and select layers of the neo‐ and allocortex. In the present study, we performed a systematic investigation of the cerebellum in eight clinically diagnosed and genetically confirmed HD patients. The cerebellum of all HD patients showed a considerable atrophy, as well as a consistent loss of Purkinje cells and nerve cells of the fastigial, globose, emboliform and dentate nuclei. This pathology was obvious already in HD brains assigned Vonsattel grade 2 striatal atrophy and did not correlate with the extent and distribution of striatal atrophy. Therefore, our findings suggest (i) that the cerebellum degenerates early during HD and independently from the striatal atrophy and (ii) that the onset of the pathological process of HD is multifocal. Degeneration of the cerebellum might contribute significantly to poorly understood symptoms occurring in HD such as impaired rapid alternating movements and fine motor skills, dysarthria, ataxia and postural instability, gait and stance imbalance, broad‐based gait and stance, while the morphological alterations (ie ballooned neurons, torpedo‐like axonal inclusions) observed in the majority of surviving nerve cells may represent a gateway to the unknown mechanisms of the pathological process of HD. 相似文献
90.