全文获取类型
收费全文 | 1349篇 |
免费 | 63篇 |
国内免费 | 12篇 |
专业分类
耳鼻咽喉 | 17篇 |
儿科学 | 49篇 |
妇产科学 | 38篇 |
基础医学 | 121篇 |
口腔科学 | 121篇 |
临床医学 | 102篇 |
内科学 | 321篇 |
皮肤病学 | 21篇 |
神经病学 | 49篇 |
特种医学 | 33篇 |
外科学 | 202篇 |
综合类 | 31篇 |
预防医学 | 69篇 |
眼科学 | 43篇 |
药学 | 107篇 |
中国医学 | 8篇 |
肿瘤学 | 92篇 |
出版年
2023年 | 12篇 |
2022年 | 35篇 |
2021年 | 63篇 |
2020年 | 25篇 |
2019年 | 40篇 |
2018年 | 53篇 |
2017年 | 31篇 |
2016年 | 34篇 |
2015年 | 40篇 |
2014年 | 53篇 |
2013年 | 76篇 |
2012年 | 112篇 |
2011年 | 112篇 |
2010年 | 61篇 |
2009年 | 68篇 |
2008年 | 69篇 |
2007年 | 65篇 |
2006年 | 76篇 |
2005年 | 77篇 |
2004年 | 57篇 |
2003年 | 47篇 |
2002年 | 41篇 |
2001年 | 15篇 |
2000年 | 15篇 |
1999年 | 8篇 |
1998年 | 10篇 |
1997年 | 4篇 |
1996年 | 8篇 |
1995年 | 8篇 |
1994年 | 6篇 |
1993年 | 4篇 |
1992年 | 8篇 |
1990年 | 3篇 |
1989年 | 7篇 |
1987年 | 4篇 |
1986年 | 4篇 |
1985年 | 7篇 |
1984年 | 7篇 |
1983年 | 9篇 |
1982年 | 4篇 |
1981年 | 4篇 |
1980年 | 3篇 |
1979年 | 7篇 |
1978年 | 8篇 |
1977年 | 4篇 |
1974年 | 3篇 |
1972年 | 2篇 |
1970年 | 3篇 |
1967年 | 2篇 |
1966年 | 2篇 |
排序方式: 共有1424条查询结果,搜索用时 15 毫秒
41.
Objectives: The aim of this study was to evaluate and compare marginal bone loss and clinical outcomes of conventionally and immediately loaded two implants supporting a ball‐retained mandibular overdenture. Materials and methods: Thirty six completely edentulous patients (22 males and 14 females) were randomly assigned into two groups. Each patient received two implants in the canine area of the mandible after a minimal flap reflection. Implants were loaded by mandibular overdentures either 3 months (conventional loading group) or the same day (immediate loading group) after implant placement. Ball attachments were used to retain all overdentures to the implants. Vertical and horizontal alveolar bone losses were evaluated in both groups 1 and 3 years after implant placement using multislice computed tomography, which allow evaluation of peri‐implant buccal and lingual alveolar bone. Plaque scores, gingival scores, probing depths and periotest values (PTVs) were evaluated at 4 months (baseline), 1 and 3 years after implant placement. Clinical and radiographic evaluations were performed at distal, labial, mesial and lingual peri‐implant sites. Results: After 3 years of follow‐up period, the immediate loading group recorded significant vertical bone loss at distal and labial sites than the conventional loading group and no significant differences in horizontal bone loss between groups were observed. Probing depth at distal and labial sites in the immediate loading group were higher than the conventional loading group, while plaque scores, gingival scores and PTVs showed no significant differences between the two groups. A low level of positive correlation between plaque scores, gingival scores, probing depths and vertical bone loss was noted. Conclusion: Immediately loaded two implants supporting a ball‐retained mandibular overdenture are associated with more marginal bone resorption and increased probing depths when compared with conventionally loaded implants after 3 years. The bone resorption and probing depths at distal and labial sites are significantly higher than those at mesial and lingual sites. Clinical outcomes do not differ significantly between loading protocols. To cite this article :Elsyad MA, Al‐Mahdy YF, Fouad MM. Marginal bone loss adjacent to conventional and immediate loaded two implants supporting a ball‐retained mandibular overdenture: a 3‐year randomized clinical trial.Clin. Oral Impl. Res. 23 , 23, 2012 496‐503.doi: 10.1111/j.1600‐0501.2011.02173.x 相似文献
42.
Trauma is the leading cause of mortality in children over one year of age in industrialized countries. In this retrospective study we reviewed all chest trauma in pediatric patients admitted to Mansoura University Emergency Hospital from January 1997 to January 2007. Our hospital received 472 patients under the age of 18. Male patients were 374 with a mean age of 9.2 ± 4.9 years. Causes were penetrating (2.1%) and blunt trauma (97.9%). The trauma was pedestrian injuries (38.3%), motor vehicle (28.1%), motorcycle crash (19.9%), falling from height (6.7%), animal trauma (2.9%), and sports injury (1.2%). Type of injury was pulmonary contusions (27.1%) and lacerations (6.9%), rib fractures (23.9%) and flail chest (2.5%), hemothorax (18%), hemopneumothorax (11.8%), pneumothorax (23.7%), surgical emphysema (6.1%), tracheobronchial injury (5.3%), and diaphragm injury (2.1%). Associated lesions were head injuries (38.9%), bone fractures (33.5%), and abdominal injuries (16.7%). Management was conservative (29.9%), tube thoracostomy (58.1%), and thoracotomy (12.1%). Mortality rate was (7.2%) and multiple trauma was the main cause of death (82.3%) (P < .001). We concluded that blunt trauma is the most common cause of pediatric chest trauma and often due to pedestrian injuries. Rib fractures and pulmonary contusions are the most frequent injuries. Delay in diagnosis and multiple trauma are associated with high incidence of mortality. 相似文献
43.
Uddin S Hussain AR Ahmed M Siddiqui K Al-Dayel F Bavi P Al-Kuraya KS 《Haematologica》2012,97(7):1092-1100
Background
FoxM1 has been shown to play a critical role in the pathogenesis of various epithelial malignancies. However, its role in lymphoid malignancies has not been fully clarified. We, therefore, investigated the role of FoxM1 expression in a large cohort of diffuse large B-cell lymphoma samples and panel of cell lines.Design and Methods
FoxM1 expression was investigated in a large series of diffuse large B-cell lymphoma tissues in a tissue microarray format by immunohistochemistry. Apoptosis was measured by flow cytometry and protein expression was detected by immunoblotting using diffuse large B-cell lymphoma cell lines following treatment with either pharmacological inhibitor of FoxM1 or small interference RNA knockdown strategy. Invasion/migration and soft agar colony assays were also performed following treatment with FoxM1 inhibitor.Results
FoxM1 expression was detected in 84.6% of diffuse large B-cell lymphoma tumors and found to be significantly associated with proliferative tumor marker Ki67 (P<0.0001), matrix metalloproteinases-2 (P=0.0008), matrix metalloproteinases-9 (P=0.0002), S-phase kinase associated protein-2 (P<0.0001) and inversely associated with p27 expression (P=0.0215). Expression of small interference RNA targeted against FoxM1 or treatment of diffuse large B-cell lymphoma cells with thiostrepton caused its downregulation accompanied by decreased expression of matrix metalloproteinases-2 and matrix metalloproteinases-9. Inhibition of FoxM1 in diffuse large B-cell lymphoma cells also decreased invasive and migratory capability, and induced caspase dependent apoptosis via activation of the mitochondrial apoptotic pathway. Finally, combined thiostrepton and bortezomib at sub-toxic doses led to efficient apoptosis in diffuse large B-cell lymphoma cells.Conclusions
Altogether, these results suggest that FoxM1 is over-expressed in the majority of diffuse large B-cell lymphoma samples. These data also indicate that targeting FoxM1 signaling can serve as a potential therapeutic modality in the management of diffuse large B-cell lymphoma. 相似文献44.
Mansoor M Alani FS Aslam MB Kumar SN Sahasrabudhe N Khan D 《European journal of gastroenterology & hepatology》2012,24(3):332-335
Plasmablastic lymphoma (PBL) is a unique type of diffuse proliferation of large neoplastic lymphoid cells most of which resemble B immunoblasts, but all tumor cells show the immunophenotype of plasma cells. It has a strong predilection for jaw and oral cavity in HIV-positive patients. Incidences of extraoral location of this tumor is increasingly being recognized especially in HIV-negative patients for example, stomach, jejunum, omentum, anorectum, lungs, testes, soft tissues, lymph nodes, bone marrow, skin, and central nervous system. We present a case of PBL found in cecum in an HIV-negative patient. It was accompanied by lung and lymph node involvement and presented as abdominal mass. This is only the second reported case of PBL originating in cecum. 相似文献
45.
46.
47.
48.
Role of endoscopic ultrasound and cyst fluid tumor markers in diagnosis of pancreatic cystic lesions
Hussein Hassan Okasha Abeer Abdellatef Shaimaa Elkholy Mohamad-Sherif Mogawer Ayman Yosry Magdy Elserafy Eman Medhat Hanaa Khalaf Magdy Fouad Tamer Elbaz Ahmed Ramadan Mervat E Behiry Kerolis Y William Ghada Habib Mona Kaddah Haitham Abdel-Hamid Amr Abou-Elmagd Ahmed Galal Wael A Abbas Ahmed Youssef Altonbary Mahmoud El-Ansary Aml E Abdou Hani Haggag Tarek Ali Abdellah Mohamed A Elfeki Heba Ahmed Faheem Hani M Khattab Mervat El-Ansary Safia Beshir Mohamed El-Nady 《World journal of gastrointestinal endoscopy》2022,14(6):402-415
49.
Maria Francesca Sfondrini Simone Gallo Benedetta Turcato Mona A. Montasser Nehal Fouad Albelasy Pekka K. Vallittu Paola Gandini Andrea Scribante 《Materials》2021,14(6)
This study aims to assess the efficacy of a universal adhesive (Scotchbond Universal, 3M ESPE) (SB) in total-etch mode, compared to a traditional orthodontic primer (Transbond XT Primer, 3M ESPE) (XT Primer), to perform bonding of orthodontic fixed retainers along with the Transbond XT Light Cure Adhesive Paste (3M ESPE). For the in vitro study, a round section wire (Ortosmail Krugg) was bonded using XT Primer for 20 bovine incisors (Group 1) and SB for other 20 (Group 2). Samples were debonded in a universal testing machine applying a tangential force to specimens (crosshead speed of 1 millimeter per minute). Shear bond strength (SBS) and adhesive remnant index (ARI) scores were calculated. For the in vivo study, 100 patients needing upper and lower canine-to-canine fixed retainers after orthodontic treatment were randomly assigned to two groups of 50 participants each, i.e., group 1 (retainer bonding with XT Primer) and group 2 (retainer bonding with SB). Over two years, examinations were carried out monthly, and detachments were registered by considering the teeth and arches affected. In vitro, no statistically significant differences in SBS and ARI scores were demonstrated between the two groups, both showing a mean bond strength of about 12 MPa and major frequency of ARI “2” (>50% remnant adhesive on the enamel). Conversely, a significantly lower failure rate over 2 years was assessed clinically for group 2 in both arches. Independently of the adhesive and arch, incisors reported a significantly higher failure rate than canines. Scotchbond Universal used in total-etch mode could be a valid alternative to the traditional orthodontic Transbond XT Primer. 相似文献
50.