全文获取类型
收费全文 | 2691篇 |
免费 | 162篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 51篇 |
儿科学 | 106篇 |
妇产科学 | 72篇 |
基础医学 | 401篇 |
口腔科学 | 16篇 |
临床医学 | 203篇 |
内科学 | 442篇 |
皮肤病学 | 64篇 |
神经病学 | 91篇 |
特种医学 | 35篇 |
外科学 | 236篇 |
综合类 | 210篇 |
一般理论 | 4篇 |
预防医学 | 190篇 |
眼科学 | 356篇 |
药学 | 176篇 |
中国医学 | 14篇 |
肿瘤学 | 187篇 |
出版年
2023年 | 15篇 |
2022年 | 60篇 |
2021年 | 85篇 |
2020年 | 69篇 |
2019年 | 48篇 |
2018年 | 64篇 |
2017年 | 40篇 |
2016年 | 63篇 |
2015年 | 83篇 |
2014年 | 104篇 |
2013年 | 144篇 |
2012年 | 178篇 |
2011年 | 171篇 |
2010年 | 117篇 |
2009年 | 70篇 |
2008年 | 150篇 |
2007年 | 151篇 |
2006年 | 108篇 |
2005年 | 107篇 |
2004年 | 120篇 |
2003年 | 117篇 |
2002年 | 111篇 |
2001年 | 81篇 |
2000年 | 95篇 |
1999年 | 69篇 |
1998年 | 30篇 |
1997年 | 15篇 |
1996年 | 16篇 |
1995年 | 16篇 |
1994年 | 18篇 |
1993年 | 10篇 |
1992年 | 24篇 |
1991年 | 30篇 |
1990年 | 30篇 |
1989年 | 18篇 |
1988年 | 21篇 |
1987年 | 16篇 |
1986年 | 13篇 |
1985年 | 14篇 |
1984年 | 10篇 |
1981年 | 7篇 |
1978年 | 8篇 |
1977年 | 9篇 |
1976年 | 9篇 |
1975年 | 10篇 |
1973年 | 10篇 |
1972年 | 9篇 |
1970年 | 7篇 |
1968年 | 11篇 |
1967年 | 7篇 |
排序方式: 共有2854条查询结果,搜索用时 0 毫秒
121.
Polymerase chain reaction for detection of Mycobacterium tuberculosis in epiretinal membrane in Eales' disease 总被引:13,自引:0,他引:13
Madhavan HN Therese KL Gunisha P Jayanthi U Biswas J 《Investigative ophthalmology & visual science》2000,41(3):822-825
PURPOSE: Tuberculous etiology has been suggested in Eales' disease. Because epiretinal membrane (ERM) is formed on the inner surface of the retina in Eales' disease, it could be the most appropriate intraocular specimen for investigation. Therefore, a nested polymerase chain reaction (nPCR), which detects MPB64 gene of Mycobacterium tuberculosis on the archival specimens of ERM of well-documented Eales' and non-Eales' patients, was applied and the results compared. METHODS: nPCR technique was standardized, and the sensitivity and specificity of the primers were determined. nPCR technique was applied to tissue sections obtained from formalin-fixed and paraffin-embedded tissues of ERM from 23 patients with Eales' disease and 27 noninfective and non-Eales' disease patients as controls. RESULTS: nPCR technique was specific for M. tuberculosis genome and sensitive enough to detect 0.25 fg (corresponding to the presence of a single bacillus). Eleven (47.8%) ERM of 23 Eales' disease and 3 (11.1%) of 27 controls were positive for M. tuberculosis genome. The difference between the two groups was statistically significant (P = 0.001), indicating association of this bacterium with Eales' disease. CONCLUSIONS: The demonstration of the presence of M. tuberculosis DNA by nPCR technique in significant number of ERM of Eales' disease compared with the controls further emphasizes the probable role of this bacterium in the pathogenesis of this enigmatic clinical condition. 相似文献
122.
PURPOSE: Although conjunctival rhinosporidiosis is endemic in India, associated scleral melting and staphyloma formation are quite rare. We report clinical features and management in three patients with this unusual presentation. METHODS: Retrospective review of case records of three patients with conjunctival rhinosporidiosis. RESULTS: Infection occurred in young, healthy adults and was localized to the forniceal conjunctiva in all patients. The affected conjunctiva had numerous grey-white spherules, but a polyp-like lesion was not present in any patient. Diagnosis was based on clinical features and examination of scrapings from the involved conjunctiva. Treatment was surgical, with excision of infected conjunctival tissues and staphyloma repair with homologous sclera or autogenous periosteum. Failure to recognize the conjunctival pathology in one patient resulted in recurrence of the staphyloma. CONCLUSION: Conjunctival rhinosporidiosis can be associated with scleral staphyloma in young, healthy, adults. Differentiating this entity from idiopathic scleral ectasia requires knowledge of the clinical features of conjunctival rhinosporidiosis and a high index of clinical suspicion. 相似文献
123.
Biswas J Samanta TK Madhavan HN Kumarasamy N Solomon S 《Indian journal of ophthalmology》2000,48(4):311-312
Anterior uveitis is a known clinical entity in herpes zoster ophthalmicus associated with AIDS. However, reports of acute haemorrhagic hypopyon uveitis in such cases are lacking. Herein we describe a young male patient presenting with acute panuveitis with haemorrhagic hypopyon, who was found HIV positive on investigation. 相似文献
124.
Eales disease--an update 总被引:22,自引:0,他引:22
Biswas J Sharma T Gopal L Madhavan HN Sulochana KN Ramakrishnan S 《Survey of ophthalmology》2002,47(3):197-214
Eales disease, first described by Henry Eales in 1880, remains an enigma. The disease, observed more commonly in the Indian subcontinent than in the rest of the world, occurs in young healthy adult males, initially presenting as retinal periphlebitis and later as retinal ischemia that may lead to vascular alterations and neovascularization. Recurrent vitreous hemorrhage with or without retinal detachment is the common sequelae. In recent years, immunological, molecular biological, and biochemical studies have indicated the role of human leukocyte antigen, retinal autoimmunity, mycobacterium tuberculosis genome, and free radical mediated damage in the etiopathogenesis of this disease. However, its etiology appears to be multifactorial. The management depends on the stage of the disease and consists of medical treatment with oral corticosteroids in the active inflammatory stage and laser photocoagulation in the advanced retinal ischemia and neovascularization stages. The results of vitreoretinal surgery have been found to be satisfactory in case of vitreous hemorrhage with or without retinal detachment. 相似文献
125.
126.
A rare case of oncocytoma of the caruncle in a 75-year-old female is reported. Clinical differential diagnosis and histopathologic features are discussed. 相似文献
127.
PURPOSE: Cytomegalovirus retinitis (CMV) is the most common ocular opportunistic infection in transplant recipients. This retrospective study attempts to report the differences in occurrence of cytomegalovirus retinetis in transplant recipients from those reported in patients with acquired immunodeficiency syndrome (AIDS). METHODS: 25 eyes of 15 transplant recipients (14 renal and one cardiac) with cytomegalovirus retinitis were retrospectively reviewed. Immunological profile included CD4+ and CD8+ T lymphocyte counts, CD4+/CD8+ cell ratio (5 cases) and serology for the viral antibodies (8 cases). RESULTS: A predominantly bilateral presentation (60%) was noted. Active cytomegalovirus retinitis (72%) in zone 2 (92%) of the inferotemporal quadrant (68%) was noted. The average cell counts were within normal limits (mean CD4 cell count-711/microliter), unlike in late stages of AIDS with cytomegalovirus retinitis (CD4 count < 50/microliter). Serology revealed an IgM positivity of 53%. Retinal detachment (52%) was the most common complication occurring after an average of 5.4 months. CONCLUSION: CMV retinitis in organ transplant recipients appears to differ from that in AIDS patients. CMV retinitis presents early and has different immunological profile, probably owing to differences in pathogenesis. 相似文献
128.
PURPOSE: To study the cytopathological features of explanted intraocular lenses (IOLs) and correlate the features with their clinical presentation. SETTING: Ocular Pathology Department, Medical and Vision Research Foundation, Sankara Nethralaya, Chennai, India. METHODS: The study comprised 61 explanted IOLs (48 posterior chamber IOLs and 13 anterior chamber IOLs) removed for the following reasons: pseudophakic bullous keratopathy (36), recalcitrant uveitis (7), retinal detachment (10), endophthalmitis (5), uveitis (7), IOL subluxation (2), and painful blind eye (1). The IOLs were stained with hematoxylin and eosin using a simple cytological technique. The cytopathological features were studied and correlated with the clinical presentations. RESULTS: The mean time of IOL explantation was 10.1 months after surgery. Twenty-one IOLs had granulomatous and nongranulomatous inflammations and 4, nongranulomatous inflammations. One IOL had fungal filaments on the surface. CONCLUSIONS: Intraocular lenses can produce both granulomatous and nongranulomatous inflammation. Granulomatous inflammation was the most common in this series. The surface of IOLs explanted because of intraocular infection may show infective agents. 相似文献
129.
130.
Receptor protein tyrosine phosphatases (RPTPs) are thought to play important functions in pathfinding and target recognition by growing neuronal processes. The leech RPTPs HmLAR1 and HmLAR2 are expressed selectively by central neurons, Comb cells, and peripheral muscle tissues in the Hirudo medicinalis embryo. To explore the functions of HmLARs, we have sought to determine their physiological substrates. We report here the cloning and embryonic expression of Lena, the leech homolog of Enabled, a cytosolic protein implicated in actin-based cell motility. Lena is expressed in embryonic central neurons and in the Comb cell. We present experimental evidences indicating that Lena associates selectively with the intracellular domain of HmLAR1 and HmLAR2. Additionally, RNA interference (RNAi) of HmLAR1 in intact leech embryos leads to the hyperphosphorylation of Lena. We propose, therefore, that Lena is an in vivo substrate of HmLAR1 in neurons and perhaps of HmLAR2 in the Comb cells. 相似文献