全文获取类型
收费全文 | 26452篇 |
免费 | 1357篇 |
国内免费 | 256篇 |
专业分类
耳鼻咽喉 | 215篇 |
儿科学 | 537篇 |
妇产科学 | 625篇 |
基础医学 | 2776篇 |
口腔科学 | 523篇 |
临床医学 | 2289篇 |
内科学 | 7756篇 |
皮肤病学 | 568篇 |
神经病学 | 2311篇 |
特种医学 | 916篇 |
外科学 | 4341篇 |
综合类 | 67篇 |
一般理论 | 5篇 |
预防医学 | 949篇 |
眼科学 | 346篇 |
药学 | 1395篇 |
中国医学 | 43篇 |
肿瘤学 | 2403篇 |
出版年
2024年 | 18篇 |
2023年 | 211篇 |
2022年 | 374篇 |
2021年 | 779篇 |
2020年 | 489篇 |
2019年 | 645篇 |
2018年 | 764篇 |
2017年 | 591篇 |
2016年 | 728篇 |
2015年 | 788篇 |
2014年 | 999篇 |
2013年 | 1378篇 |
2012年 | 2130篇 |
2011年 | 2088篇 |
2010年 | 1231篇 |
2009年 | 1099篇 |
2008年 | 1916篇 |
2007年 | 1817篇 |
2006年 | 1660篇 |
2005年 | 1673篇 |
2004年 | 1537篇 |
2003年 | 1352篇 |
2002年 | 1254篇 |
2001年 | 181篇 |
2000年 | 125篇 |
1999年 | 176篇 |
1998年 | 228篇 |
1997年 | 206篇 |
1996年 | 164篇 |
1995年 | 186篇 |
1994年 | 152篇 |
1993年 | 140篇 |
1992年 | 100篇 |
1991年 | 83篇 |
1990年 | 93篇 |
1989年 | 57篇 |
1988年 | 49篇 |
1987年 | 39篇 |
1986年 | 50篇 |
1985年 | 53篇 |
1984年 | 57篇 |
1983年 | 41篇 |
1982年 | 54篇 |
1981年 | 32篇 |
1980年 | 44篇 |
1979年 | 25篇 |
1978年 | 15篇 |
1977年 | 17篇 |
1975年 | 19篇 |
1974年 | 20篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Pelosi G Scarpa A Veronesi G Spaggiari L Del Curto B Moore PS Maisonneuve P Sonzogni A Masullo M Viale G 《Virchows Archiv : an international journal of pathology》2005,447(6):969-977
Nuclear translocation of β-catenin has been correlated with epidermal growth factor receptor (EGFR) overexpression/activation
in nonsmall cell lung cancer. Less is known on β-catenin transactivation in high-grade pulmonary neuroendocrine tumors and
on the status of β-catenin activating EGFR and human epidermal growth factor receptor 2 (HER-2) or β-catenin target genes
cyclin D1 and matrix metalloproteinase-7 (MMP-7). β-catenin immunoreactivity was evaluated in 51 large-cell neuroendocrine
carcinomas (LCNEC) and 45 small-cell lung carcinomas (SCLC). Nineteen cases were assessed for β-catenin gene exon 3 mutations, expression of MMP-7, and expression/gene amplification of EGFR, HER-2, and cyclin D1. β-catenin was
expressed in all 96 high-grade neuroendocrine tumors, the vast majority (94%) showing >50% immunopositive cells. A disarrayed
immunoreactivity, however, was commonly encountered consisting in variably altered membrane-associated patterns of staining
along with progressive accumulation of cytoplasmic immunoreactivity. In LCNEC, but not in SCLC, the disarrayed patterns correlated
with EGFR and HER-2 protein expression. β-catenin nuclear accumulation was found in nine tumors, including seven LCNEC and
two SCLC, and was always associated with disarrayed immunoreactivity and increased MMP-7, but not cyclin D1 expression. These
cases, however, did not show β-catenin gene mutations or EGFR and HER-2 gene amplification or expression. No association was found between nuclear β-catenin and
any clinicopathological variable including patients' survival. The subcellular compartmentalization of β-catenin is profoundly
altered in high-grade pulmonary neuroendocrine tumors. A minor subset of these tumors shows β-catenin nuclear accumulation
in association with increased expression of MMP-7, but not of cyclin D1, independent of EGFR and HER-2 gene amplification
or expression.
The authors have no significant financial or other relationship with the manufacturers of any commercial products or commercial
services presented in this paper 相似文献
102.
Chiara Leoni Elizabeth Katherine Anna Triumbari Catello Vollono Roberta Onesimo Maria Podagrosi Valentina Giorgio Eliza Kuczynska Stefania Veltri Marco Tartaglia Giuseppe Zampino 《American journal of medical genetics. Part A》2019,179(6):940-947
Pain in individuals with RASopathies is a neglected topic in literature. In this article, we assessed prevalence and profile of pain in a sample of 80 individuals affected by RASopathies. The study sample included individuals with Noonan syndrome (N = 42), Costello syndrome (N = 17), and cardio‐facio‐cutaneous syndrome (N = 21). A set of standardized questionnaires and scales were administered (VAS/numeric scale, r‐FLACC, Wang‐Baker scale, NPSI, BPI, NCCPC‐R) to detect and characterize acute and chronic pain and to study the influence of pain on quality of life (PEDs‐QL, SF‐36) and sleeping patterns (SDSC); revision of past medical history and multisystemic evaluation was provided. Available clinical data were correlated to the presence of pain. High prevalence of acute (44%) and chronic (61%) pain was documented in the examined sample. Due to age and intellectual disability, acute pain was localized in 18/35 individuals and chronic pain in 33/49. Muscle‐skeletal and abdominal pain was more frequently reported. The intensity of acute and chronic pain interfered with daily activities in 1/3 of the sample. Pain negatively impacted on QoL and sleeping patterns. This work documents that pain is highly prevalent in RASopathies. Future studies including subjective and objective measures of pain are required to discriminate a somatosensory abnormality from an abnormal elaboration of painful stimuli at a central level. 相似文献
103.
104.
Colacurci N Chiàntera A Fornaro F de Novellis V Manzella D Arciello A Chiàntera V Improta L Paolisso G 《Menopause (New York, N.Y.)》2005,12(3):299-307
OBJECTIVE: To evaluate the effects of soy isoflavone administration on endothelial function in healthy postmenopausal women. DESIGN: Sixty naturally postmenopausal women were randomly assigned to receive isoflavone or placebo tablets for 6 months. Endothelium-dependent vasodilatation was measured by brachial reactivity technique along with levels of plasma soluble intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin, P-selectin and soluble thrombomodulin, von Willebrand factor, and tissue plasminogen activator. Differences between endothelium-dependent and endothelium-independent vasodilatation were assessed by evaluating brachial reactivity parameters after reactive hyperemia and after sublingual administration of nitroglycerin; furthermore, in the active group, the effect of isoflavones was also evaluated during the intra-arterial infusion of N-monomethyl-L-arginine. Serum levels of lipids [high-density lipoprotein and low-density lipoprotein cholesterol, triglycerides and lipoprotein(a)] and hemostatic factors (prothrombin, fibrinogen, plasminogen activator inhibitor-1, and fibrin D-dimer) were also measured. To confirm the absorption of isoflavones, their blood concentrations were determined. RESULTS: Isoflavone treatment versus placebo was associated with a significant improvement in endothelium-dependent vasodilatation but had no impact on endothelial-independent arterial diameter and flow. Intra-arterial infusion of N-monomethyl-L-arginine inhibited the significant effect of isoflavones on endothelium-mediated vasodilatation. Furthermore, isoflavone group experienced statistically significant reductions in plasma concentrations of ICAM-1, VCAM-1, and E-selectin. Levels of soluble thrombomodulin, von Willebrand factor, tissue plasminogen activator, lipids, and hemostatic factors did not change significantly throughout the study in both groups. CONCLUSIONS: Our findings suggest a positive influence of soy isoflavones on endothelial function in healthy postmenopausal women as evidenced by an improvement in endothelium-dependent vasodilatation and a reduction in plasma adhesion molecule levels. 相似文献
105.
O'Brien SG Guilhot F Larson RA Gathmann I Baccarani M Cervantes F Cornelissen JJ Fischer T Hochhaus A Hughes T Lechner K Nielsen JL Rousselot P Reiffers J Saglio G Shepherd J Simonsson B Gratwohl A Goldman JM Kantarjian H Taylor K Verhoef G Bolton AE Capdeville R Druker BJ;IRIS Investigators 《The New England journal of medicine》2003,348(11):994-1004
106.
Ferdinando Iellamo Jacopo Maria Legramante Filippo Castrucci Michele Massaro Gianfranco Raimondi Giuseppe Peruzzi Giuseppe Tallarida 《European journal of applied physiology》1993,66(5):381-387
Summary In recent studies in humans the role of cardiopulmonary baroreflexes in modulating the cardiovascular responses to isometric exercise (somatic pressor reflex) has been investigated by performing static hand-grip exercise during deactivation of cardiopulmonary receptors produced by low levels of lower body negative pressure; however, findings from these studies have not been consistent. The purpose of this study was to investigate whether a more physiological unloading stimulus of cardiopulmonary baroreceptors, obtained by sequentially changing posture, could influence the pressor response to somatic afferent stimulation induced by isometric, exercise. To accomplish this, ten healthy subjects performed a 2-min isometric handgrip (IHG) at 30% maximal voluntary contraction after 10 min of supine rest and, in rapid sequence, after 10 min of sitting and 10 min of standing, at the time when, owing to their transitory nature, the cardiovascular effects, due to arterial baroreceptor intervention should have been minimal. During IHG arterial pressure (BPa) was continuously and noninvasively measured to quantify accurately the blood pressure response to IHG both in magnitude and time course. Results showed that the pressor response to IHG was not significantly influenced by change in posture, either in magnitude or in time course. The mean arterial pressure increased by 17.4 (SEM 2.5), 18.6 (SEM 1.2) and 17.0 (SEM 1.3) mmHg in supine, sitting and standing [2.3 (SEM 0.3), 2.5 (SEM 0.2) and 2.3 (SEM 0.2) kPa] positions, respectively. Also the heart rate response to IHG was unaffected by change in posture. Most important, the sum of the separate BPa responses induced by supine IHG and by posture change from supine to sitting (summation of reflexes) was not significantly different from the pressor response observed during sitting IHG (interaction of reflexes). Likewise, the sum of the separate BPa. responses induced by sitting IHG and by changing postures from sitting to standing was not significantly different from the pressor response to standing IHG. These data indicate that, under physiological conditions, cardiopulmonary baroreflexes do not exert a significant role in modulating the reflex pressor drive from muscles during isometric exercise in healthy humans. 相似文献
107.
N19 polyepitope as a carrier for enhanced immunogenicity and protective efficacy of meningococcal conjugate vaccines 总被引:2,自引:0,他引:2 下载免费PDF全文
Baraldo K Mori E Bartoloni A Petracca R Giannozzi A Norelli F Rappuoli R Grandi G Del Giudice G 《Infection and immunity》2004,72(8):4884-4887
N19, a string of human universal CD4 T-cell epitopes from various pathogen-derived antigens, was shown to exert a stronger carrier effect than CRM197 for the induction of anti-group C Neisseria meningitidis capsular polysaccharide (MenC), after immunization of mice with various dosages of N19-MenC or CRM-MenC conjugate vaccines. After two immunizations, the N19-based construct induced anti-MenC antibody and protective bactericidal antibody titers higher than those induced by three doses of the CRM-MenC conjugate and required lower amounts of conjugate. N19-based conjugates are superior to CRM-based conjugates to induce protective immune responses to MenC conjugates. 相似文献
108.
Genes and translocations involved in POF 总被引:14,自引:0,他引:14
109.
Giuliano M Bellavia G Lauricella M D'Anneo A Vassallo B Vento R Tesoriere G 《International journal of molecular medicine》2004,13(4):565-571
A potent inhibitor of serine/threonine kinases, staurosporine exerts antiproliferative and apoptotic effects in many cancer cells, although the exact mechanism of its action is still unclear. This study examines the effects of staurosporine on Chang liver cells, an immortalized non-tumor cell line, in comparison with those caused in HuH-6 and HepG2 cells, two human hepatoma cell lines. Our results provide evidence that staurosporine promotes apoptosis in Chang liver cells as observed by flow cytometric analysis and acridine orange/ethidium bromide staining. The effect appeared already after 8 h of treatment and increased with treatment time and dose. After 48 h of exposure to 200 nM staurosporine clear apoptotic signs were observed in about 50% of the cells. Western blotting analysis showed that in Chang liver cells staurosporine induced a marked decrease in the levels of the antiapoptotic factors Bcl-2 (-75%) and Bcl-XL (-50%). Staurosporine also caused loss of mitochondrial transmembrane potential, release of cytochrome c from mitochondria and activation of caspase-3. The involvement of caspases in staurosporine-induced cell death was also suggested by the observation that the addition of z-VAD-fmk, a general inhibitor of caspases, suppressed apoptosis. In HuH-6 and HepG2 cells treatment with staurosporine induced the arrest of cells in G2/M phase of cell cycle. This effect was not modified by z-VAD-fmk and was not accompanied by the appearance of biochemical signs of apoptosis. We conclude that staurosporine induced apoptosis in Chang liver cells by a mitochondria-caspase-dependent pathway which was closely correlated with a decrease in Bcl-2 and Bcl-XL levels, while in HuH-6 and HepG2 hepatoma cells the drug caused only an antiproliferative effect. 相似文献
110.
Rolla G Nebiolo F Marsico P Guida G Bigo P Riva G Zanotta S 《International archives of allergy and immunology》2004,135(4):293-295
BACKGROUND: The European tick, Argas reflexus, is an urban pest parasitizing urban pigeons and may cause a wide range of allergic reactions. METHODS: Specific IgE to A. reflexus, SDS-PAGE and IgE immunoblotting, performed with tick extract, were carried out in the sera of 6 patients who reported allergic reactions after tick bite. RESULTS: Specific IgE to A. reflexus (RAST class ranging from 1 to 3) were detected in the sera of 6 patients who reported allergic reactions (urticaria and angioedema in 2 and anaphylaxis in the other 4 patients) after tick bite. IgE reactivity to two bands of 22 and 40 kDa were identified in the patient sera. CONCLUSIONS: Allergy to A. reflexus has to be considered in allergic patients living in buildings where pigeons have their nests. The powerful sensitizing property of tick allergen is underlined by the observation that none of our patients was atopic. 相似文献