全文获取类型
收费全文 | 1403篇 |
免费 | 78篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 20篇 |
妇产科学 | 9篇 |
基础医学 | 182篇 |
口腔科学 | 11篇 |
临床医学 | 157篇 |
内科学 | 352篇 |
皮肤病学 | 28篇 |
神经病学 | 91篇 |
特种医学 | 86篇 |
外科学 | 249篇 |
综合类 | 9篇 |
一般理论 | 1篇 |
预防医学 | 62篇 |
眼科学 | 26篇 |
药学 | 69篇 |
中国医学 | 1篇 |
肿瘤学 | 120篇 |
出版年
2022年 | 9篇 |
2021年 | 21篇 |
2020年 | 17篇 |
2019年 | 17篇 |
2018年 | 22篇 |
2017年 | 19篇 |
2016年 | 32篇 |
2015年 | 37篇 |
2014年 | 48篇 |
2013年 | 46篇 |
2012年 | 102篇 |
2011年 | 107篇 |
2010年 | 79篇 |
2009年 | 53篇 |
2008年 | 101篇 |
2007年 | 91篇 |
2006年 | 79篇 |
2005年 | 86篇 |
2004年 | 75篇 |
2003年 | 64篇 |
2002年 | 56篇 |
2001年 | 15篇 |
2000年 | 23篇 |
1999年 | 14篇 |
1998年 | 16篇 |
1997年 | 10篇 |
1996年 | 7篇 |
1994年 | 6篇 |
1992年 | 17篇 |
1991年 | 13篇 |
1990年 | 14篇 |
1989年 | 14篇 |
1988年 | 11篇 |
1987年 | 11篇 |
1986年 | 11篇 |
1985年 | 9篇 |
1984年 | 9篇 |
1983年 | 7篇 |
1980年 | 4篇 |
1979年 | 8篇 |
1978年 | 10篇 |
1974年 | 6篇 |
1973年 | 4篇 |
1972年 | 7篇 |
1971年 | 4篇 |
1970年 | 5篇 |
1967年 | 5篇 |
1966年 | 5篇 |
1965年 | 4篇 |
1949年 | 7篇 |
排序方式: 共有1481条查询结果,搜索用时 15 毫秒
101.
102.
Effects of verteporfin therapy on central visual field function 总被引:5,自引:0,他引:5
Schmidt-Erfurth UM Elsner H Terai N Benecke A Dahmen G Michels SM 《Ophthalmology》2004,111(5):931-939
PURPOSE: To evaluate the effect of photodynamic therapy with verteporfin on the maintenance of central visual field function. DESIGN: Randomized controlled clinical trial. PARTICIPANTS: Forty-six consecutive patients with subfoveal choroidal neovascularization (CNV) caused by age-related macular degeneration including a classic component were randomly assigned. Thirty-three participants received standard verteporfin therapy, and 13 received placebo and laser treatment. METHODS: The trial was performed as a single-center, double-masked study. Patients were examined before therapy and continuously in 3-month intervals during 2 years of follow-up. A scanning laser ophthalmoscope (SLO) was used to perform macular microperimetry. Absolute and relative scotomas were documented at each visit, and size was measured in square millimeters. MAIN OUTCOME MEASURES: The change in size of central scotoma in the verteporfin group compared with the placebo group. RESULTS: An absolute scotoma was seen in 88%, and a relative scotoma was seen in 100% of eyes before therapy. Absolute defects were associated with the classic CNV component localized angiographically. In the verteporfin group, the absolute scotoma grew from 2.5 mm(2) at baseline to a final size of 7.3 mm(2) at month 24. In the placebo group, the mean lesion size of the absolute scotoma enlarged from an initial size of 2.7 mm(2) to 31.5 mm(2) after 24 months. The relative scotoma increased from 7.9 mm(2) at baseline to 20.8 mm(2) at month 24 in the verteporfin group, whereas a progression from 8.5 mm(2) initially to 48.3 mm(2) at the final presentation was measured in the placebo group. Statistical analysis showed that both the mean absolute and relative scotoma sizes were significantly smaller in the verteporfin group than the placebo group for all intervals from 6 to 24 months (P<0.001). CONCLUSIONS: Documentation of macular function with SLO perimetry demonstrated a significant benefit of verteporfin therapy for the preservation of the central visual field. Absolute and relative scotoma sizes remained smaller after therapy. This may influence reading ability and visual rehabilitation. 相似文献
103.
Cilengitide (EMD 121974) arrests the growth of a heavily pretreated highly vascularised head and neck tumour 总被引:5,自引:0,他引:5
The suppression and eradication of malignant tumours by targeting the endothelial cells of the tumour is one of the rapidly evolving new approaches to cancer therapy. Head and neck tumours, because of their high levels of vascularization, present themselves as ideal candidates for such antiangiogenic strategies. We report a heavily pretreated patient with a tumour 15 cm in diameter representing fourth relapse of squamous cell carcinoma, which had its origin in the upper left jaw. The patient was treated with the antiangiogenetic, cyclic peptide, EMD 121974 [cilengitide] (600 mg/m2 over 60 minutes i.v.) on day 1 and 4 in combination with gemcitabine (1000 mg/m2 over 30 minutes) administered days 1 and 8 every 3 weeks for five months, and a partial remission was achieved. This resulted in a clinical improvement in the ability of the patient to eat and smell. The patient remained stable for 12 months on cilengitide mainenance therapy, with no tendency towards spontaneous bleeding. This clinical case demonstrates the clinical efficacy of the antiangiogenetic agent cilengitide, in combination with gemcitabine, in inhibiting rapid growth of highly vascularized tumour and highlights the potential of this new therapeutic agent 相似文献
104.
Anterior cruciate reconstruction combined with autologous osteochondral transplantation 总被引:1,自引:0,他引:1
Hans-Michael?KlingerEmail author Mike?H.?Baums Stephanie?Otte Hanno?Steckel 《Knee surgery, sports traumatology, arthroscopy》2003,11(6):366-371
The purpose of this prospective study was to evaluate the results of simultaneous anterior cruciate ligament (ACL) reconstruction and osteochondral autograft transplantation performed in patients suffering an anterior instability associated with symptomatic full-thickness cartilage defects. Our clinical report includes the first 21 patients (six women, 15 men) who have been followed up for 32 months or longer. The average patient age was 29 years (range 22–44 years), and mean time from injury to the combined reconstructive surgery was 10 months (range 4–27 months). The cartilage defects had a mean area of 3.5 cm2 (range 2.0–5.0 cm2). All patients were evaluated according to the IKDC, Lysholm and Tegner scoring scales by an independent observer. A visual analogue scale (VAS) reflecting patient pain was evaluated. Assessment using the IKDC knee scoring scale revealed 81% of the patients with a normal or nearly normal knee joint. There was a significant improvement in subjective discomfort, and the KT-1000 arthrometric evaluation showed a reduction of the ventral tibial translation (5.9 to 1.9 mm). All but two patients had returned to full activities without restriction and were asymptomatic. The results of this study suggest that symptomatic full-thickness articular cartilage defects associated with ACL instability can be effectively treated by performing ACL reconstruction and osteochondral autologous grafts in one procedure. However, only the years which follow will show the long-term outcome of the patients. 相似文献
105.
Unusual cross-sectional imaging findings in hepatic peliosis 总被引:1,自引:0,他引:1
Hepatic peliosis is a rare entity that represents focal, multifocal, segmental, or diffuse dilatation of liver sinusoids.
Hepatic peliosis is often associated with chronic wasting diseases but also has been reported in association with anabolic,
contraceptive, or other hormonal treatment, and even in context with HIV-related bacterial infections. Hepatic peliosis is
usually clinically unapparent and mostly found only during autopsy, but occasionally it may lead to diagnostic problems if
detected radiologically since the imaging findings in hepatic peliosis are quite variable according to the variety of its
possible histologic features as well as the possibility of additional hemorrhage. We present a case of hepatic peliosis associated
with bronchial carcinoma that showed moderate centripetal enhancement during the portal-venous phase on CT, pronounced venous
pooling on contrast enhanced T1-weighted images acquired during the hepatic-venous phase, and bright signal on T2-weighted
images, thus mimicking in some way a capillary hemangioma. We also discuss some not yet described CT and MR features of this
rare entity which should be included into the differential diagnosis of atypical liver lesions in patients with the above-mentioned
conditions. 相似文献
106.
Dissociations among functional subsystems governing melody recognition after right-hemisphere damage
This study describes an amateur musician, KB, who became amusic following a right-hemisphere stroke. A series of assessments conducted post-stroke revealed that KB functioned in the normal range for most verbal skills. However, compared with controls matched in age and music training, KB showed severe loss of pitch and rhythmic processing abilities. His ability to recognise and identify familiar instrumental melodies was also lost. Despite these deficits, KB performed remarkably well when asked to recognise and identify familiar song melodies presented without accompanying lyrics. This dissociation between the ability to recognise/identify song vs. instrumental melodies was replicated across different sets of musical materials, including newly learned melodies. Analyses of the acoustical and musical features of song and instrumental melodies discounted an explanation of the dissociation based on these features alone. Rather, the results suggest a functional dissociation resulting from a focal brain lesion. We propose that, in the case of song melodies, there remains sufficient activation in KB's melody analysis system to coactivate an intact representation of both associative information and the lyrics in the speech lexicon, making recognition and identification possible. In the case of instrumental melodies, no such associative processes exist; thus recognition and identification do not occur. 相似文献
107.
Steinke K Gananadha S King J Zhao J Morris DL 《Surgical laparoscopy, endoscopy & percutaneous techniques》2003,13(6):366-371
Pad burns during or after radiofrequency ablation (RFA) are a skin complication probably underreported in the literature. We report on 4 severe pad burns, deep second and third degree, in 3 patients undergoing radiofrequency ablation of liver malignancies, 1 percutaneously and the other 2 after laparotomy. All burns occurred at the leading edge or at the corner of the pads attached to the patients' thighs. Potential causes leading to the burns are discussed. Current dispersive pad designs do not prevent the leading edge phenomenon and subsequent burns. Further developmental work in the pad design with the possibility of skin temperature monitoring via temperature sensors under the leading pad edge is needed. 相似文献
108.
Roder HM 《Journal of molecular neuroscience : MN》2003,20(2):197-201
Alois Alzheimer described the concurrence of two conspicuous proteinacious aggregates in 1906. Today it is clear that the two types of protein aggregates are fundamentally different. One consists of a short fragment (Abeta peptide) of a membrane protein APP and is found mainly outside of cells and the other is formed from a biochemically modified cytoskeleton-associated protein known as tau. The latter is found exclusively inside cells. Aggregated tau in all tauopathies including AD is abnormally modified by the excess incorporation of chemical groups called phosphates (hyperphosphorylation), and the appearance of this biochemical change coincides with the onset all tauopathies, suggesting that it is both a necessary and sufficient cause for such diseases. Data indicate that the basis for tau hyperphosphorylation is the dysregulation of key enzymes known as kinases. These enzymes are therapeutic targets for AD and other neurodegenerative diseases, which feature pathological tau structures in brain 相似文献
109.
110.
Carotid artery disease was assessed in 180 patients by means of color Doppler flow imaging. Color Doppler findings in 360 carotid arteries were compared with the results of standard Doppler sonography, and color Doppler findings in 60 bifurcations were compared with the results of intraarterial angiography. The sensitivity of color Doppler for the detection of carotid disease was 100% when compared with angiography. The accuracy of color Doppler in classifying minor (40-60%), moderate (61-80%), and severe (81-90%) stenosis ranged from 91.3% to 97.8% vs standard Doppler sonography, and from 91.7% to 95.8% vs angiography. Whereas all occlusions were identified correctly by both color Doppler and angiography, four pseudoocclusions of the carotid artery were misdiagnosed as occluded. Characteristic features providing reliable criteria of the degree of stenosis are (1) intensity, extent, and duration of color fading; (2) postprocessed systolic peak frequency; (3) plaque extent on serial sonograms; and (4) poststenotic flow patterns. Display of hemodynamic disturbances induced by less pronounced plaques showed highly variable patterns that could not be anticipated from the plaque morphology alone. Thus, color Doppler preserves the advantages of standard Doppler and duplex sonography but provides additional information about otherwise anechoic necrotic and thrombotic material that often causes cerebral embolisms. With atherogenesis, repair mechanisms may be sustained or progression be stopped by reducing the risk factors and instituting medical treatment; thus, the application of this noninvasive technique is important. 相似文献