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排序方式: 共有4462条查询结果,搜索用时 31 毫秒
71.
《International journal of oral and maxillofacial surgery》2020,49(2):169-175
Chronic vascular rejection characterized by the myointimal proliferation of smooth muscle cells that progressively obstruct the arterial graft lumen may become the main cause of long-term graft loss in vascularized composite allotransplantation (VCA), as observed in solid organ transplantation. As such, new diagnostic tools are required. The objective of this study was to evaluate the usefulness of flow magnetic resonance imaging (MRI) in the qualitative and quantitative monitoring of VCA in three patients transplanted between 2005 and 2012. Seven flow MRI acquisitions were performed concurrently with standardized clinical and histological monitoring between 2015 and 2017. A progressive reduction in the average flow rate and intraluminal diameter of the arterial pedicle of the grafts was demonstrated. During follow-up, two patients developed chronic vascular rejection requiring partial resection of the graft. For these patients, flow MRI acquisitions were characterized by a significant reduction in vascular signal, with a reduction in intravascular flow prior to anatomical injury. The results of this study confirm the feasibility of reproducible, non-invasive, and non-operator-dependent morphometric and haemodynamic radiological analysis, providing clinicians with new information on the vascular status of VCA over time and offering the prospect of an imaging technique specific to vascular outflow. 相似文献
72.
L'Huillier I Cottin Y Touzery C Zeller M Beel JC Fraison M Verges B Louis P Brunotte F Wolf JE 《International journal of cardiology》2003,90(2-3):165-173
Objective: This study was designed to assess the prognostic value of myocardial tomoscintigraphy perfusion imaging after percutaneous coronary intervention (PCI) in asymptomatic diabetic patients. Methods: One hundred and fourteen diabetic patients were followed up during 27±16 (mean±SD) months after the myocardial tomoscintigraphy. PCI-related events were studied after myocardial tomoscintigraphy stress testing and included major cardiac events (MACE) (cardiovascular death, myocardial infarction) and revascularization (bypass surgery or new PCI). Stress myocardial tomoscintigraphy imaging was performed 5±5 months after PCI and ischemia was considered as present if at least 2 contiguous segments were showing reversible defects. Results: Persistent silent ischemia was found in 49/114 (43%) patients. No difference was observed between the two groups for MACE: four among the 65 (6%) non ischemic patients versus 2 among the 49 (4%) ischemic patients (NS). In contrast, 15 (31%) among the ischemic patients and 4 (6%) among the non ischemic patients underwent iterative revascularization (p<0.01). The relative risk of revascularization for patients with significant ischemia was 5.5 versus non ischemic patients (p<0.001). Conclusion: After PCI, in asymptomatic diabetic patients followed by myocardial tomoscintigraphy a high frequency of persistent silent ischemia was found and associated with a high risk for repeat interventional procedure, although no increase in major cardiac events was observed. 相似文献
73.
Dong-Ni Zhou Qing-Qing Yang Zhong-Lin Li Zhi-Yong Pan Yan-Fei Deng 《International journal of clinical and experimental pathology》2015,8(5):4277-4283
Head and neck rhabdomyosarcoma (HNRMS) is exceedingly rare and poorly documented. The difficult diagnosis often causes a poor prognosis and high mortality. Hence, we report 4 cases of HNRMS and their follow-up outcomes, and review the clinicopathological features of this rare tumor. The 4 patients ranged in age from 5 to 29 years. Among them, 3 patients had a good prognosis after combination of radiotherapy and chemotherapy or surgery alone. Another patient survived for only 3 months after diagnosis without therapy. Deeply insight into HNRMS might improve the ability of diagnosis and treatment for this disease. 相似文献
74.
Li-Chang Zhong Feng Lu Fang Ma Hui-Xiong Xu Dan-Dan Li Le-Hang Guo Li-Ping Sun 《International journal of clinical and experimental pathology》2015,8(3):3155-3159
Purpose: The management criterion of thyroid nodules is to evaluate the risk of malignancy, based on cytological examinations. Ultrasound-guided fine-needle aspiration biopsy (US-FNAB) has a highly diagnostic value for thyroid nodules. The aim of this study was to compare the efficacy of US-FNAB for thyroid nodules with different sizes. Material and methods: From August 2013 to November 2013, 344patients with thyroid nodules who had undergone US-FNAB were divided into three groups, according to the largest diameter of their nodules (group A, ≤ 5.0 mm; group B, 5.1-10.0 mm; group C, > 10.0 mm). All the nodules were subsequently verified by histology or follow-up findings. The accuracy, sensitivity, specificity, positive predictive value, negative predictive value of aspiration cytology in each group was compared. Results: Among 344 thyroid nodules diagnosed by cytology, the cytology was classified as nondiagnostic or unsatisfactory for 53 (15.4%) lesions, benign for 144 (41.9%) lesions, atypia of undetermined significance or follicular lesion of undetermined significance for 20 (5.8%) lesions, follicular neoplasm or suspicious for a follicular neoplasm for 26 (7.6%) lesions, suspicious for malignancy for 36 (10.5%) lesions, malignant for 65 (18.9%) lesions. There were 243 benign and 101 malignant nodules confirmed by the pathological or follow-up ultrasound. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were confirmed to be 87.5% (14/16), 92.5% (37/40), 91% (51/56), 82.3% (14/17), and 94.8% (37/39) in group A; 92.3% (36/39), 96.9% (94/97), 95.5% (130/136), 92.3% (36/39), and 96.9% (94/97) in group B; and 91.3% (42/46), 93.4% (99/106), 92.7% (141/152) 85.7% (42/49), and 96.1% (99/103), in group C. There were no statistical differences in accuracy, sensitivity, specificity, false positive accuracy, false negative rate of fine needle aspiration of thyroid nodules with different sizes (P > 0.05). Conclusion: US-FNAB has similar diagnostic efficacy to thyroid nodules with different sizes. 相似文献
75.
76.
目的:对Cerec3计算机辅助设计与辅助制作(CAD-CAM)系统制作的种植体上部全瓷冠进行6年随访,评价其远期效果,以期为临床提供参考。方法:使用Cerec3 CAD-CAM系统对植入36例患者的缺牙区的40颗种植体进行上部全瓷冠的CAD-CAM修复,定期随访,末次随访时参照改良美国加州牙科协会评价标准对CAD-CAM全瓷冠进行评价,同时对患者进行满意度问卷调查,并进行Kapl an-Mei er生存率分析。结果:除7件CAD-CAM全瓷冠失败外,其余33件CAD-CAM全瓷冠随访70个月-80个月。除费用外,患者对其余指标的满意度达100%。Ka-pl an-Mei er生存率分析显示,CAD-CAM全瓷冠的6年留存率为82.5%。结论:Cer ec3 CAD-CAM系统制作的种植体上部全瓷冠可在口腔环境中长期保存并行使功能。 相似文献
77.
The present study examines the association between repetition of suicide attempts and sociodemographic and psychopathological characteristics of patients during a 5-year follow-up period. Participants were 874 suicide attempters referred to the University Hospital of Ghent, among whom 361 (41.3%) patients were available for follow-up analysis. Within 5 years, 29.2% of those admitted for an index suicide attempt repeated non-fatal suicidal behavior. Repetition of suicidal behavior was associated with high scores on measures of psychopathology. In addition, the risk of repetition was increased if the patient was female, aged between 20 and 49, and had a lower education. Multivariate analysis showed significant results for age, the Buglass & Horton Risk of Repetition Scale and for anxiety. Repetition of suicidal behavior is associated with high anxiety, severe depression, more psychiatric symptoms and is increased in young patients. 相似文献
78.
Background
Drug-metabolizing enzymes (DMEs) inhibition based drug-drug interaction and herb-drug interaction severely challenge the R&D process of drugs or herbal ingredients.Objective
To evaluate the inhibition potential of wogonin (an important flavonoid isolated from the root of Scutellaria baicalensis) towards one of the most important phase II DMEs, UDP-glucuronosyltransferase (UGT) 1A9.Methods
Both recombinant UGT1A9-catalyzed 4-methylumbelliferone (4-MU) glucuronidation reaction and human liver microsomes (HLMs)-catalyzed propofol glucuronidation reaction were used as two different probe reactions.Results
Wogonin noncompetitively inhibited recombinant UGT1A9-catalyzed 4-MU glucuronidation, and exerted competitive inhibition towards HLMs-catalyzed propofol glucuronidation. The inhibition kinetic parameters (Ki) were calculated to be 3.2 µM and 52.0µM, respectively.Conclusion
Necessary monitoring was needed when wogonin was co-administered with the clinical drugs mainly undergoing UGT1A9-mediated glucuronidation elimination. Additionally, probe reactions-dependent inhibition of wogonin towards the activity of UGT1A9 should be paid attention when translating these in vitro data into in vivo situation. 相似文献79.
Gunvor Bentung Lygre Nils Roar Gjerdet Lars Björkman 《Acta odontologica Scandinavica》2013,71(5):258-263
The Dental Biomaterials Adverse Reaction Unit in Bergen, Norway, is a national unit for the examination of patients with suspected adverse reactions to dental materials. The aim of this study was to investigate whether patients with suspected adverse reactions to dental materials experienced improvement in health after dental restorations had been replaced, and whether they had acted according to the recommendations of the Unit. A questionnaire was sent to 358 patients who had been examined at the Unit 18 months to 7 years earlier. Of the 207 patients who completed the questionnaire, 85 had had restorative materials replaced with other types of materials. A majority had had amalgam fillings replaced. After replacement, 51 patients reported an improvement in health. Twelve patients reported that they felt worse after replacement. The Unit recommended replacement of materials in 31 patients, of whom 24 followed the recommendation. Among 176 patients who were not given specific recommendations as to replacement of dental materials, 67 had had their restorations replaced, and 40 had started to have them replaced. It appears that the examination at the Dental Biomaterials Adverse Reaction Unit is one of several inputs that influence a person's decision to replace dental materials. 相似文献
80.
《Renal failure》2013,35(6):718-721
Antenatal hydronephrosis (AHN), defined as dilatation of renal pelvis and/or calyces, is the most frequently detected antenatal abnormality. However, postnatal management of AHN is controversial. The purpose of this study was to describe the clinical outcomes of infants with AHN and to contribute to the definition of the postnatal evaluation of these patients. One hundred and thirty-six infants with AHN were prospectively followed up to 18 months. Patients were divided into two groups according to the degree of sonographic hydronephrosis (HN) on days 5–7: group I (n = 87, 64%) included patients who had grades 1 and 2 (64%) and group II (n = 49, 36%) included patients who had grade 3 and above HN. The grade of HN was found to be correlated with the increased risk of urologic pathologies. Frequency of vesicoureteral reflux was found to be significantly lower in patients with mild HN (6%) as compared to patients with severe AHN (29%) (p = 0.005). In addition, the risk of urinary tract infection increases with increasing grades of HN (10% vs. 29%, p = 0.006). The frequency of spontaneous resolution in patients with mild AHN (64%) was also significantly higher than in patients with severe HN (29%) (p < 0.001). The degree of AHN can be used for making decision about further diagnostic imaging and treatment. Our results strongly suggest that low-grade HN is a relatively self-limited condition and needs minimal investigation. In contrast, the outcome of more severe degrees of AHN needs clarification. 相似文献