全文获取类型
收费全文 | 2411篇 |
免费 | 262篇 |
国内免费 | 17篇 |
专业分类
耳鼻咽喉 | 52篇 |
儿科学 | 44篇 |
妇产科学 | 32篇 |
基础医学 | 80篇 |
口腔科学 | 888篇 |
临床医学 | 119篇 |
内科学 | 145篇 |
皮肤病学 | 44篇 |
神经病学 | 98篇 |
特种医学 | 49篇 |
外科学 | 876篇 |
综合类 | 100篇 |
预防医学 | 50篇 |
眼科学 | 8篇 |
药学 | 81篇 |
1篇 | |
中国医学 | 5篇 |
肿瘤学 | 18篇 |
出版年
2024年 | 9篇 |
2023年 | 84篇 |
2022年 | 87篇 |
2021年 | 141篇 |
2020年 | 125篇 |
2019年 | 132篇 |
2018年 | 142篇 |
2017年 | 108篇 |
2016年 | 110篇 |
2015年 | 123篇 |
2014年 | 187篇 |
2013年 | 171篇 |
2012年 | 102篇 |
2011年 | 113篇 |
2010年 | 99篇 |
2009年 | 101篇 |
2008年 | 107篇 |
2007年 | 138篇 |
2006年 | 102篇 |
2005年 | 61篇 |
2004年 | 65篇 |
2003年 | 59篇 |
2002年 | 44篇 |
2001年 | 38篇 |
2000年 | 30篇 |
1999年 | 14篇 |
1998年 | 24篇 |
1997年 | 21篇 |
1996年 | 22篇 |
1995年 | 26篇 |
1994年 | 19篇 |
1993年 | 16篇 |
1992年 | 7篇 |
1991年 | 9篇 |
1990年 | 10篇 |
1989年 | 2篇 |
1987年 | 7篇 |
1986年 | 5篇 |
1985年 | 3篇 |
1984年 | 3篇 |
1983年 | 1篇 |
1982年 | 4篇 |
1981年 | 3篇 |
1980年 | 2篇 |
1979年 | 5篇 |
1978年 | 6篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有2690条查询结果,搜索用时 15 毫秒
31.
S. Shousha A. Schoenfeld Jill Moss I. Shore H. D. Sinnett 《Ultrastructural pathology》1994,18(5):519-523
Although recent epidemiologic studies suggest that silicone augmentation of the breast is not associated with an increased risk of mammary carcinoma, cases of breast carcinoma arising in augmented breasts are being increasingly encountered as a large number of patients who had augmentation are getting older. A case of a 51-year-old woman with a 20-year history of breast augmentation who developed an invasive cribriform carcinoma associated with extensive microcalcification is presented. The patient had submammary silicone implants 20 years ago that were replaced, because of local complications, in subpectoral positions 10 years later. Dispersive X-ray microanalysis failed to demonstrate silicone in sections of the tumor and adjacent breast tissue. Appropriately fixed tumor tissue was available for electron microscopic examination. The tumor cells were rich in mitochondria, and their luminal surfaces were endowed with abundant microvilli, but the cell surfaces that came closest to the calcified microspheriols were devoid of microvilli and had cellular buddings between the microspheriols. It is suggested that the tumor cells might have been actively involved in the process of microcalcification. 相似文献
32.
C. Mirone F. Albert† A. Tosi‡ F. Mocchetti‡ S. Mosca M. Giorgino S. Pecora§ S. Parmiani§ C. Ortolani 《Clinical and experimental allergy》2004,34(9):1408-1414
BACKGROUND: The allergological relevance of Ambrosia in Europe is growing but the efficacy of the injective immunotherapy for this allergen has been documented only in Northern America. OBJECTIVE: We sought to study the safety and efficacy of injective immunotherapy in European patients sensitized to Ambrosia artemisiifolia. METHODS: Thirty-two patients (18 M/14 F, mean age 36.78, range 23-60 years) suffering from rhinoconjunctivitis and/or asthma and sensitized to Ambrosia were enrolled and randomized in a double-blind, placebo-controlled (DBPC) study lasting 1 year. A maintenance dose corresponding to 7.2 microg of Amb a 1 was administered at 4-week intervals after the build-up. During the second and the third year, all patients were under active therapy in an open fashion. Symptom and medication scores, skin reactivity to Ambrosia (parallel line biological assay), and pollen counts were assessed throughout the trial. RESULTS: Twenty-three patients completed the trial. No severe adverse event was observed. During the DBPC phase, actively treated patients showed an improvement in asthmatic symptoms (P=0.02) and drug (P=0.0068) scores days with asthmatic symptoms (P=0.003), days with rhinitis symptoms (P=0.05), and days with intake of drugs (P=0.0058), as compared to before therapy. No improvement for any of these parameters was detected in the placebo group. Moreover, the number of days with rhinitis and asthma was significantly higher in the placebo as compared to the active group (P=0.048 and P<0.0001, respectively). Patients who switched from placebo to active therapy improved in rhinoconjunctivitis, asthma, and drug intake. The skin reactivity decreased significantly (12.2-fold, P=0.0001) in the active group whereas a slight increase (1.07-fold, P=0.87) was observed in the placebo group after the DBPC phase. After switching to active therapy, patients previously under placebo showed a significant decrease of this parameter (4.78-fold, P=0.002). CONCLUSION: Injective immunotherapy is safe and clinically effective in European patients sensitized to Ambrosia. 相似文献
33.
Kaoru Takakusaki Jun Kohyama Kiyoji Matsuyama Shigemi Mori 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1993,93(3):471-482
Intrapontine microinjections of serotonin in acutely decerebrated cats resulted in the bilateral augmentation of the postural muscle tone of the hindlimbs. Optimal injection sites were located in the dorsomedial part of the rostral pontine reticular formation corresponding to the nucleus reticularis ponds oralis (NRPo). In this study, attempts were made to elucidate the cellular basis for the serotoninergically induced augmentation of postural muscle tone by recording the electromyographic (EMG) activity of hindlimb extensor muscles, the monosynaptic reflex responses evoked by electrical stimulation of group Ia muscle afferent fibres and the membrane potentials of hindlimb alpha-motoneurons (MNs). Serotonin injections resulted not only in the augmentation of the EMG activity of gastrocnemius soleus muscles, but also in the restoration of EMG suppression, which was induced by previous injection of carbachol into the NRPo. Extensor and flexor monosynaptic reflex responses were facilitated by serotonin injections into the NRPo. Such reflex facilitation was not induced by serotonin injections into the mesencephalic or the medullary reticular formation. Intrapontine serotonin injections resulted in membrane depolarization of extensor and flexor MNs with decreases in input resistance and rheobase. Spontaneous depolarizing synaptic potentials (EPSPs) increased in both frequency and amplitude. Peak voltage of Ia monosynaptic EPSPs also increased. Serotonin injections which followed carbachol injections resulted in membrane depolarization of MNs along with an increase in the frequency of spontaneous EPSPs and a decrease in carbachol-induced inhibitory postsynaptic potentials. Following pontine carbachol injections, antidromic and orthodromic responses in MNs were suppressed. Discharges of MNs evoked by intracellular current injections were also suppressed, but were restored following serotonin injections. These results indicate that postsynaptic excitation, presynaptic facilitation and disinhibition (withdrawal of postsynaptic inhibition) simultaneously act on the hindlimb MNs during serotonin-induced postural augmentation and restoration. 相似文献
34.
Tolbert S. Wilkinson M.D. Barry E. Swartz M.D. I. Richard Toranto M.D. 《Aesthetic plastic surgery》1985,9(2):79-85
Based on prior experience with implant exposure, an aggressive regimen to eradicate periprosthetic infections has proven successful in delayed gram-positive and gram-negative bacterial infections and in atypical microbacterial infections. The objective of the salvage procedure is to retain a prosthesis, to maintain breast contour, and to avoid psychological and physical consequences of prosthesis removal. The salvage procedure involves topical antisepsis, contracture release if needed, systemic and topical antibiotics with intermittent or continuous irrigation, and reinforcement of incision lines in selected cases using local tissue flaps. 相似文献
35.
Rolf Muenker M.D. 《Aesthetic plastic surgery》1984,8(1):37-42
The most common procedures to reconstruct a severe saddle-nose deformity are autogenous costal cartilage, iliac bone grafting, or Silastic implants. Each of them has its specific disadvantages. As an alternative solution, an autogenous bilateral conchal graft in sand-wich technique is described. A 3-layer graft for the dorsum and a 2-layer graft to support the depressed columellar-tip area grants a more natural and elastic reconstruction of the nasal framework. The conchal grafts are taken by an incision made on the preauricular surface of the ear. How to plane the curved grafts by meticulous cross-hatching and to immobilize them in the recipient area by transcutaneous suturing is demonstrated.Presented at the VIII International Congress of Plastic and Reconstructive Surgery, Montreal, Canada, June, 1983 相似文献
36.
37.
Poor tendon to bone healing following rotator cuff repair has led to the continued interest and investigation into biological augmentation. The biology of tendinopathy is not fully understood and consequently the availability of disease modifying therapeutic targets is limited. A ceiling of benefit has been reached by mechanical optimisation of rotator cuff repair and thus, in order to improve healing rates, a biological solution is required. This review focuses on the strategies to biologically augment rotator cuff disorders with an emphasis on rotator cuff repair. Leucocyte rich platelet rich plasma has been shown to improve healing rates without clinically relevant improvements in outcome scores. Similarly, improved healing rates have also been reported with bone marrow stimulation and in long-term follow-up with bone marrow concentrate. Extracellular matrix (ECM) and synthetic scaffolds can increase healing through mechanical and or biological augmentation. A potential third category of scaffold is bio-inductive and has no mechanical support. Studies involving various scaffolds have shown promising results for augmentation of large to massive tears and is likely to be most beneficial when tendon quality is poor, however level I evidence is limited. 相似文献
38.
Safety of injectable autologous human fibroblasts 总被引:3,自引:0,他引:3
Keller G Sebastian J Lacombe U Toft K Lask G Revazova E 《Bulletin of experimental biology and medicine》2000,130(8):786-789
Autologous dermal fibroblasts after propagation in cell culture were used for face soft tissue augmentation. Twenty patients
aged 37–61 years with facial rhytides and atrophic scars were treated with autologous fibroblasts from cell culture. Significant
sustained clinical improvement was observed. Cells of early passages (4, 5, 6) were used for injection. The study showed that
cultured fibroblasts were functionally active and produced large quantities of type I collagen.In vitro studies of scar formation potency of injectable fibroblasts showed that these cells possessed normal collagen gel contraction
capacity.In vivo experiments showed that cultured fibroblasts exhibited no oncogenic properties and induced no tumors in nude mice.
Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 130, No. 8, pp. 203–206, August, 2000 相似文献
39.
血管内超声(IVUS)图像是观测血管内部结构的首选影像学手段,基于IVUS图像的内膜和中外膜边界的提取是实现冠脉粥样硬化精准诊断的前提和关键。针对IVUS图像结构复杂、对比度低、边界提取困难等问题,本研究提出一种基于改进TransUnet网络的分割方法。首先,针对IVUS图像边界提取难点,对边血管、血管分叉、导丝伪像、阴影等4种图像结构进行建模,并基于建模结果予以定向数据增强;而后,结合IVUS图像的环状结构分布特点,在TransUnet网络中提出了Polar-bias归纳偏置的策略,并对IVUS图像进行像素级的分类;最后,基于分类结果优化GVF snake模型的外力场,进而提取IVUS图像的内膜和中外膜边界。采用国际标准IVUS图像数据集(两组不同中心频率,共512幅图像)对算法进行评测,引入JMard距离(JM),Hausdorff距离(HD)和面积差异百分比(PAD)等3个评测指标,在数据集A中JM为0.87, HD为0.87, PAD为0.18,数据集B中JM为0.91, HD为0.25, PAD为0.08。实验结果表明,所提出的算法在两组数据集的内膜及中外膜提取问题中的表现均... 相似文献
40.
R. Büttemeyer R. Hohlc W. Meyer-Gattermann J. C. Bruck 《European journal of plastic surgery》1994,17(1):23-27
Summary Three cases of homologous and one of autologous free fat block transplantation for breast augmentation were seen 10 to 20 years after operation due to late complications. Displacement of heavy tumors, local mastitis or disrupted capsules following local trauma led to admission. The calcified centrally necrotic cysts were treated by subcutaneous mastectomy or local enucleation and immediate reconstruction by subpectoral augmentation with silicone-gel implants or reduction mammoplasty. 相似文献