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排序方式: 共有319条查询结果,搜索用时 0 毫秒
1.
Atul K Madan Constantine T Frantzides Christopher L Tebbit William C Park Nakka V Aruna Kumari Nina Shervin 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2004,8(2):191-193
BACKGROUND: Laparoscopic suturing and tying constitute advanced minimally invasive surgery skills. Developing proficiency in the standard methods with needle drivers is often an arduous process. Recent advances in laparoscopic instrumentations has allowed for easier methods of suturing and tying. This study investigated the hypothesis that the use of a specialized suturing device and a specialized tying device allows inexperienced medical students to suture and tie laparoscopically. METHODS: Preclinical medical students who had not received any training in open or laparoscopic surgery were included in this investigation. Each student was given a 5-minute demonstration of a specialized suturing device and a specialized tying device. The medical students were not allowed to deploy either device before actual use. After the demonstration, each student was given the device to use in a porcine model. Times were recorded and a subjective grade was given for each student. RESULTS: Twenty medical students were involved in this study. All medical students were able to complete the task of suturing and tying. The average time to suture was 104.6 seconds and the average time to tying was 31.2 seconds. The average subjective performance grade was 90 (out of 100). CONCLUSION: Specialized devices are easy to learn and use for laparoscopic suturing and tying with minimal instruction even for inexperienced medical students. Even surgeons who are not well versed in laparoscopic surgery should be able to suture and tie with certain laparoscopic instruments. 相似文献
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Negin Badihian Roya Riahi Parvin Goli Shervin Badihian Parnian Poursafa Roya Kelishadi 《Autoimmunity reviews》2021,20(6):102823
ObjectiveBoth genetic and environmental factors play roles in Multiple Sclerosis (MS) etiopathogenesis. The relationship between prenatal/perinatal factors/exposures and future MS occurrence in the offspring remains controversial. Here, we aimed to review the available evidence on prenatal/perinatal factors associated with later MS occurrence.MethodWe performed systematic search of PubMed, Web of Science, and Scopus from inception to October 2020. We included original observational studies conducted on human participants addressing the association between prenatal/perinatal factors and MS occurrence. Data were extracted according to the PRISMA guideline. The adjusted odds ratio (OR) with 95% confidence interval (CI) was considered as the desired effect size. The heterogeneity was evaluated by Cochran's Q and I2 and the publication bias was assessed. We excluded gestational/neonatal vitamin D level, season of birth, and latitude because of recently published systematic reviews/meta-analyses on these subjects.ResultsOverall, 2306 records were identified in the primary search. After excluding irrelevant studies, we evaluated 34 studies with contributing data on 100 prenatal/perinatal factors associated with an increased or decreased risk of MS occurrence. In the meta-analyses, we found no statistically significant associations between later MS occurrence in offspring and prenatal smoking exposure (OR = 1.01, 95% CI = 0.77–1.34), mode of delivery (OR = 0.90, 95% CI = 0.52–1.56), birth order (OR = 0.85, 95% CI = 0.72–1.00), and maternal age (OR = 1.34, 95% CI = 0.88–2.04). Paternal age and parents' marital status at the time of childbirth, maternal preeclampsia/ toxemia, forceps use, birth weight, plurality, and preterm birth were the other most studied factors, and none reported to affect MS risk.ConclusionWe found that prenatal smoking exposure, mode of delivery, birth order, and maternal age do not affect risk of future MS development. Moreover, most of the other investigated factors were reported not to affect MS risk in the offspring. 相似文献
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Frech Tracy M. VanBuren John M. Startup Emily Assassi Shervin Bernstein Elana J. Castelino Flavia V. Chung Lorinda Correia Chase Gordon Jessica K. Hant Faye N. Hummers Laura Khanna Dinesh Sandorfi Nora Shah Ami A. Shanmugam Victoria K. Steen Virginia Evnin Luke 《Clinical rheumatology》2021,40(3):965-971
Clinical Rheumatology - The objective of this analysis is to examine whether the severity of systemic sclerosis (SSc)-hand involvement influences patient-reported outcome measure (PROM) completion... 相似文献
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Kaviani MJ Malekzadeh R Vahedi H Sotoudeh M Kamalian N Amini M Massarrat S 《European journal of gastroenterology & hepatology》2001,13(8):915-919
INTRODUCTION: One of the most economical and effective therapeutic regimens for eradication of Helicobacter pylori is the classic triple therapy with amoxycillin or tetracycline, metronidazole and a bismuth derivative. Addition of H2-receptor antagonists to these drugs may heighten the rate of eradication and shorten the duration. We therefore performed a randomized controlled trial comparing twice daily metronidazole, bismuth derivative and amoxycillin for 2 weeks with additional ranitidine for 1 or 2 weeks. PATIENTS AND METHODS: In total, 240 adult patients with duodenal ulcer and H. pylori infection were randomly assigned to one of the following regimens: (1) amoxycillin 1 g bid, metronidazole 500 mg bid, bismuth sub-citrate 240 mg bid and ranitidine 300 mg bid for 1 week; (2) triple therapy without ranitidine for 2 weeks; or (3) triple therapy plus ranitidine 300 mg bid for 2 weeks. Side-effects of the drugs were evaluated two weeks after starting the treatment. The rapid urease test and histology from antrum and corpus, and/or 14C- urea breath test were used to determine H. pylori eradication six weeks after starting the treatment. RESULTS: In total, 195 patients were followed up for 6 weeks. The most frequent drug side-effects were unpleasant taste (46%), dry mouth (41%) and fatigue (26%), which had an equal distribution in all treatment groups. Endoscopy and 14C- urea breath test were performed for 178 and 123 patients, respectively. Eradication of H. pylori was documented in 19/64 (29.7%), 29/63 (46%) and 50/68 (73.5%) of patients in groups 1, 2 and 3, respectively (P < 0.000001 for group 1 versus group 3; P < 0.0014 for group 2 versus group 3; difference not significant for group 1 versus group 2). An intention-to-treat analysis showed eradication rates of 19/80 (23.75%), 29/80 (36.25%) and 50/80 (62.5%) for groups 1, 2 and 3, respectively. At four weeks post-treatment, the most sensitive test for evaluation of eradication of H. pylori was histology. CONCLUSION: Although combined use of an H2-receptor antagonist and twice daily triple therapy in a two-week regimen is more effective than two-week triple or one-week quadruple therapy in Iranian patients, none of these regimens is ideal in countries with a probable high rate of resistant and strongly toxic strains of H. pylori. 相似文献
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Carmona FD Gutala R Simeón CP Carreira P Ortego-Centeno N Vicente-Rabaneda E García-Hernández FJ García de la Peña P Fernández-Castro M Martínez-Estupiñán L Egurbide MV Tsao BP Gourh P Agarwal SK Assassi S Mayes MD Arnett FC Tan FK Martín J;Spanish Scleroderma Group 《Annals of the rheumatic diseases》2012,71(1):114-119
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Hessam Nowzari DDS PhD Shervin Molayem DDS Ching Hsiu Ketty Chiu DDS Sandra K. Rich RDH PhD 《Clinical implant dentistry and related research》2012,14(4):595-602
Background: The initial thickness of maxillary bone has significant impact on the responding level of facial bone and soft tissue after extraction and immediate implant placement. A prevailing notion is that following implant placement in fresh extraction sites, at least 2 mm of facial bone is needed to prevent soft tissue recession, fenestration, and dehiscence. Purpose: The purpose of this study was to use cone beam computed tomography (CBCT) to measure horizontal width of facial alveolar bone overlying healthy maxillary central incisors and to determine prevalence of bone thickness ≥2 mm. Materials and Methods: Tomographic data from 101 randomly selected patients were evaluated by two independent observers. Assessments were made of facial bone width at levels 1.0 to 10.0 mm apical to the bone crest. Results: Healthy maxillary central incisors (n = 202) were measured from 101 patient scans. The percent of teeth with facial bone ≥2 mm at levels 1, 2, 3, 4, and 5 mm from the bone crest was 0, 1.5, 2.0, 3.0, and 2.5%, respectively. Overall mean thickness of the bone was 1.05 mm for right and left central incisors combined. The range of individual measurements for all levels was 0 to 5.1 mm. The occurrence of ≥2 mm thickness bone measurements increased with increasing depth. However, mean widths observed at levels 6 to 10 mm from the crest ranged only 1.0 to 1.3 mm because of apparent fenestration occurrence (0 mm bone) in approximately 12% of teeth. Overall, no significant differences in bone thickness were found between ethnic, gender, age, or scan groups. Conclusions: Using CBCT, occurrences of ≥2 mm maxillary facial alveolar bone were found on no more than 3% of root surfaces 1.0 to 5.0 mm apical to the bone crest in this sample of maxillary central incisors. The study evidenced prevalence of a thin facial alveolar bone (<2 mm) that may contribute to risk of facial bone fenestration, dehiscence, and soft tissue recession after immediate implant therapy. 相似文献
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