全文获取类型
收费全文 | 7106篇 |
免费 | 541篇 |
国内免费 | 29篇 |
专业分类
耳鼻咽喉 | 82篇 |
儿科学 | 170篇 |
妇产科学 | 108篇 |
基础医学 | 1054篇 |
口腔科学 | 167篇 |
临床医学 | 677篇 |
内科学 | 1684篇 |
皮肤病学 | 94篇 |
神经病学 | 671篇 |
特种医学 | 280篇 |
外科学 | 1061篇 |
综合类 | 69篇 |
一般理论 | 5篇 |
预防医学 | 517篇 |
眼科学 | 131篇 |
药学 | 352篇 |
中国医学 | 8篇 |
肿瘤学 | 546篇 |
出版年
2023年 | 60篇 |
2022年 | 101篇 |
2021年 | 189篇 |
2020年 | 136篇 |
2019年 | 170篇 |
2018年 | 206篇 |
2017年 | 152篇 |
2016年 | 169篇 |
2015年 | 204篇 |
2014年 | 272篇 |
2013年 | 347篇 |
2012年 | 549篇 |
2011年 | 530篇 |
2010年 | 342篇 |
2009年 | 280篇 |
2008年 | 498篇 |
2007年 | 471篇 |
2006年 | 419篇 |
2005年 | 423篇 |
2004年 | 346篇 |
2003年 | 327篇 |
2002年 | 298篇 |
2001年 | 74篇 |
2000年 | 64篇 |
1999年 | 82篇 |
1998年 | 67篇 |
1997年 | 55篇 |
1996年 | 51篇 |
1995年 | 54篇 |
1994年 | 36篇 |
1993年 | 50篇 |
1992年 | 55篇 |
1991年 | 50篇 |
1990年 | 41篇 |
1989年 | 45篇 |
1988年 | 42篇 |
1987年 | 37篇 |
1986年 | 29篇 |
1985年 | 26篇 |
1984年 | 29篇 |
1983年 | 27篇 |
1982年 | 29篇 |
1981年 | 27篇 |
1980年 | 14篇 |
1979年 | 22篇 |
1978年 | 17篇 |
1975年 | 13篇 |
1974年 | 17篇 |
1973年 | 13篇 |
1972年 | 15篇 |
排序方式: 共有7676条查询结果,搜索用时 15 毫秒
1.
Maria C. Chammas Andre C. Oliveira Mario J. D´Ávilla Pedro H. Moraes Marcelo Straus Takahashi 《Ultrasound in medicine & biology》2019,45(1):50-55
We prospectively evaluated the effectiveness of contrast-enhanced ultrasonography (CEUS) for differentiation of benign versus malignant portal vein thrombosis (PVT). We studied a total of 43 patients with chronic liver disease, hepatocellular carcinoma-suggestive nodules and confirmed PVT, in whom the nature of the PVT was confirmed by follow-up imaging (US, computed tomography and/or magnetic resonance imaging) performed up to 6 mo after CEUS. PVT was assessed by US, Doppler US and CEUS with respect to vessel wall disruption and/or invasion, color Doppler vascularization, pulsed Doppler vascularization pattern and CEUS enhancement and vascularization pattern, and thrombi were classified as benign or malignant based on these findings. Follow-up studies revealed malignant PVT in 22 of the 43 patients (51%) and benign PVT in 21 patients (49%). CEUS findings were consistent with follow-up studies in 41 of the 43 patients (95%), with κ?=?0.903 (p < 0.0001), sensitivity?=?91% and specificity?=?100%, indicating that CEUS can be confidently used to differentiate benign from malignant portal vein thrombosis in the setting of chronic liver disease. 相似文献
2.
Fibromyalgia is a syndrome of widespread pain, nonrestorative sleep, disturbed mood, and fatigue. Optimal treatment involves
a multidisciplinary approach with a team of health care providers using pharmacologic and nonpharmacologic treatment. Because
of the heterogeneity of the illness, management should be individualized for the patient. Pharmacologic treatment should address
issues of pain control, sleep disturbance, fatigue, and any underlying coexisting mood disorder. Nonpharmacologic treatment
should include patient education, a regular exercise and stretching program, and cognitive behavioral therapy. All of these
are essential to improving functional capacity and quality of life. This review provides general guidelines in initiating
a successful pharmacologic treatment program for patients with fibromyalgia. 相似文献
3.
4.
5.
6.
7.
Ellen J Schlette L Jeffrey Medeiros Andre Goy Raymond Lai George Z Rassidakis 《Journal of clinical oncology》2004,22(9):1682-1688
PURPOSE: Survivin, a member of the inhibitor of apoptosis (IAP) family, is not detected in normal adult tissues but is overexpressed in various cancers, including some types of lymphoma. The frequency and prognostic significance of survivin expression in anaplastic large-cell lymphoma (ALCL) is unknown. Materials and METHODS: We assessed for survivin expression in 62 ALCL tumors (30 anaplastic lymphoma kinase [ALK]-positive and 32 ALK-negative) obtained before doxorubicin-based chemotherapy. Given that survivin is a target of the STAT3 signaling pathway and STAT3 is activated in ALCL, survivin expression was also correlated with STAT3 activation. RESULTS: Survivin was expressed in 34 tumors (55%) and did not correlate with ALK. A significant association between survivin expression and STAT3 activation was observed (P =.007, Fisher's exact test). For the ALK-positive group, the 5-year failure-free survival (FFS) was 34% for patients with survivin-positive ALCL compared with 100% for patients with survivin-negative ALCL (P =.009, log-rank test). For the ALK-negative group, the 5-year FFS was 46% for patients with survivin-positive tumors compared with 89% for patients with survivin-negative tumors (P =.03, log-rank test). Overall survival was similarly worse for patients with survivin-positive tumors in both the ALK-positive and ALK-negative groups. Furthermore, multivariate analysis confirmed the independent prognostic value of survivin expression, along with age older than 60 years and Ann Arbor stage III or IV. CONCLUSION: Survivin is expressed in approximately half of ALCL tumors and independently predicts unfavorable clinical outcome. Modulation of survivin expression or function may provide a novel target for experimental therapy in patients with ALCL. 相似文献
8.
Nhân Pham-Thi Pierre Scheinmann Riad Fadel Anne Combebias Claude Andre the Study Group 《Pediatric allergy and immunology》2007,18(1):47-57
Although several studies have demonstrated the efficacy of subcutaneous immunotherapy in allergic asthma, few have shown the same benefit using sublingual immunotherapy (SLIT) in asthmatic patients. This study was conducted to assess the efficacy of house dust mite (HDM) SLIT in addition to allergen avoidance and standard pharmacologic treatment. A double-blind, placebo-controlled trial was performed in 111 children (aged 5-15 yr) with HDM-induced mild-to-moderate asthma. After a 4-week baseline phase, patients were randomly assigned to receive SLIT with tablets of HDM extract (n = 55) or placebo (n = 56) for 18 months. Pharmacologic treatment was adjusted every 3 months following a step-down approach. Asthma symptom scores, reduction in use of inhaled corticosteroids and inhaled beta(2)-agonists, rhinitis symptoms, lung function tests, skin sensitivity to HDM, dust mite-specific immunoglobulin (Ig) E and IgG(4), and quality of life (QoL) were assessed during the study. After 18 months of treatment, diurnal and nocturnal asthma symptoms scores did not show significant differences between SLIT and placebo groups. Inhaled corticosteroids and inhaled beta(2)-agonists use was reduced in both groups without significant differences between groups. There were no significant differences in lung function (forced expiratory volume in 1 s and peak flow rate variations) between groups. Rhinitis symptom score decreased in both groups, with no difference between the two groups. The severity dimension of QoL was significantly improved in the SLIT group (age 6-12 yr). SLIT induced a significant reduction of skin sensitivity to HDM (p < 0.01) and a significant increase in HDM-specific IgE and IgG(4) antibodies (p < 0.001) in the SLIT group compared with the placebo group. SLIT was well tolerated with mild/moderate local adverse events. No severe systemic reactions were reported. This study indicates that, when mild-moderate asthmatic children are optimally controlled by pharmacologic treatment and HDM avoidance, SLIT does not provide additional benefit, despite a significant reduction in allergic response to HDM. Under such conditions, only a complete, but ethically unfeasible, discontinuation of inhaled corticosteroid would have demonstrated a possible benefit of SLIT. 相似文献
9.
10.
Polyclonal antibodies recognizing the pyridyloxobutyl (POB) moiety of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) were produced in rabbits immunized either with POB-bovine albumin or POB-Sepharose. The POB intermediates necessary to modify the protein were generated by alkaline (pH 9.0) treatment of the synthetic precursor 4-(carbethoxynitrosamino)-1-(3-pyridyl)-1-butanone. In a competitive enzyme linked immunoabsorbent assay (ELISA), 70 pmole NNK inhibited 50% of the binding of the anti-POB antibodies to POB-protein absorbed on microtiterplates. This 50% inhibition varied from 70 pmole to 200 nmole using a series of NNK analogues, depending on the integrity of the POB moiety. Immunological techniques initiated in this study detect NNK-protein conjugates or measure the quantity of POB groups liberated upon alkaline or acid treatment of NNK modified protein. 相似文献