全文获取类型
收费全文 | 6364篇 |
免费 | 272篇 |
国内免费 | 80篇 |
专业分类
耳鼻咽喉 | 79篇 |
儿科学 | 117篇 |
妇产科学 | 307篇 |
基础医学 | 641篇 |
口腔科学 | 206篇 |
临床医学 | 482篇 |
内科学 | 1685篇 |
皮肤病学 | 86篇 |
神经病学 | 370篇 |
特种医学 | 324篇 |
外科学 | 1174篇 |
综合类 | 25篇 |
一般理论 | 1篇 |
预防医学 | 203篇 |
眼科学 | 339篇 |
药学 | 237篇 |
中国医学 | 4篇 |
肿瘤学 | 436篇 |
出版年
2024年 | 4篇 |
2023年 | 67篇 |
2022年 | 62篇 |
2021年 | 194篇 |
2020年 | 116篇 |
2019年 | 175篇 |
2018年 | 225篇 |
2017年 | 118篇 |
2016年 | 167篇 |
2015年 | 165篇 |
2014年 | 254篇 |
2013年 | 366篇 |
2012年 | 499篇 |
2011年 | 586篇 |
2010年 | 361篇 |
2009年 | 357篇 |
2008年 | 490篇 |
2007年 | 547篇 |
2006年 | 500篇 |
2005年 | 441篇 |
2004年 | 342篇 |
2003年 | 260篇 |
2002年 | 198篇 |
2001年 | 35篇 |
2000年 | 16篇 |
1999年 | 15篇 |
1998年 | 37篇 |
1997年 | 20篇 |
1996年 | 22篇 |
1995年 | 17篇 |
1994年 | 9篇 |
1993年 | 5篇 |
1992年 | 9篇 |
1990年 | 2篇 |
1989年 | 7篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 1篇 |
1984年 | 8篇 |
1983年 | 6篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1978年 | 1篇 |
1977年 | 1篇 |
排序方式: 共有6716条查询结果,搜索用时 15 毫秒
991.
Nikolaos Smyrnis Foteini Protopapa Evangelos Tsoukas Allison Balogh Constantinos I. Siettos Ioannis Evdokimidis 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2014,232(2):659-673
This study investigated the question whether spatial working memory related to movement plans (motor working memory) and spatial working memory related to spatial attention and perceptual processes (perceptual spatial working memory) share the same neurophysiological substrate or there is evidence for separate motor and perceptual working memory streams of processing. Towards this aim, ten healthy human subjects performed delayed responses to visual targets presented at different spatial locations. Two tasks were attained, one in which the spatial location of the target was the goal for a pointing movement and one in which the spatial location of the target was used for a perceptual (yes or no) change detection. Each task involved two conditions: a memory condition in which the target remained visible only for the first 250 ms of the delay period and a delay condition in which the target location remained visible throughout the delay period. The amplitude spectrum analysis of the EEG revealed that the alpha (8–12 Hz) band signal was smaller, while the beta (13–30 Hz) and gamma (30–45 Hz) band signals were larger in the memory compared to the non-memory condition. The alpha band signal difference was confined to the frontal midline area; the beta band signal difference extended over the right hemisphere and midline central area, and the gamma band signal difference was confined to the right occipitoparietal area. Importantly, both in beta and gamma bands, we observed a significant increase in the movement-related compared to the perceptual-related memory-specific amplitude spectrum signal in the central midline area. This result provides clear evidence for the dissociation of motor and perceptual spatial working memory. 相似文献
992.
Aikaterini Patsatsi M.D. Ph.D. Miltiadis Kokolios M.D. Olga Pikou M.D. Vasilios Lambropoulos M.D. Ph.D. Ioannis Efstratiou M.D. Ph.D. Dimitrios Sotiriadis M.D. Ph.D. 《Pediatric dermatology》2016,33(6):e366-e367
Regression of congenital nevi is usually associated with loss of pigment or halo formation. In rare cases, regression is characterized by sclerosis and hair loss. We describe a rare case of a sclerotic hypopigmented large congenital melanocytic nevus in which a localized scleroderma‐like reaction process of regression seemed to have started in utero and progressed throughout early childhood. 相似文献
993.
Ioannis S Papanikolaou Georgios Tziatzios Alexandros Chatzidakis Antonio Facciorusso Stefano Francesco Crin Paraskevas Gkolfakis Gjorgi Deriban Mario Tadic Goran Hauser Antonios Vezakis Ivan Jovanovic Nicola Muscatiello Anna Meneghetti Konstantinos Miltiadou Kalina Stardelova Alojzije Lacković Maria-Zoi Bourou Srdjan Djuranovic Konstantinos Triantafyllou 《World journal of gastrointestinal endoscopy》2021,13(9):416-425
BACKGROUND Coronavirus disease 2019(COVID-19) significantly affected endoscopy practice,as gastrointestinal endoscopy is considered a risky procedure for transmission of infection to patients and personnel of endoscopy units(PEU).AIM To assess the impact of COVID-19 on endoscopy during the first European lockdown(March-May 2020).METHODS Patients undergoing endoscopy in nine endoscopy units across six European countries during the period of the first European lockdown for COVID-19(MarchMay 2020) were included. Prior to the endoscopy procedure, participants were stratified as low-or high-risk for potential COVID-19 infection according to the European Society of Gastrointestinal Endoscopy(ESGE) and the European Society of Gastroenterology and Endoscopy Nurses and Associates(ESGENA) joint statement, and contacted 7-14 d later to assess COVID-19 infection status. PEU were questioned regarding COVID-19 symptoms and/or infection via questionnaire, while information regarding hospitalizations, intensive care unitadmissions and COVID-19-related deaths were collected. The number of weekly endoscopies at each center during the lockdown period was also recorded.RESULTS A total of 1267 endoscopies were performed in 1222 individuals across nine European endoscopy departments in six countries. Eighty-seven(7%) were excluded because of initial positive testing. Of the 1135 pre-endoscopy low risk or polymerase chain reaction negative for COVID-19, 254(22.4%) were tested post endoscopy and 8 were eventually found positive, resulting in an infection rate of 0.7% [(95%CI: 0.2-0.12]. The majority(6 of the 8 patients, 75%) had undergone esophagogastroduodenoscopy. Of the 163 PEU, 5 [3%;(95%CI: 0.4-5.7)] tested positive during the study period. A decrease of 68.7%(95%CI: 64.8-72.7) in the number of weekly endoscopies was recorded in all centers after March 2020. All centers implemented appropriate personal protective measures(PPM) from the initial phases of the lockdown.CONCLUSION COVID-19 transmission in endoscopy units is highly unlikely in a lockdown setting, provided endoscopies are restricted to emergency cases and PPM are implemented. 相似文献
994.
Ioannis A Ziogas Muhammad H Hayat Georgios Tsoulfas 《World Journal of Transplantation》2020,10(11):320-329
An increasing number of childbearing agewomen undergo liver transplantation (LT) in the United States. Transplantation in this patient subgroup poses a significant challenge regarding the plans for future fertility, particularly in terms of immunosuppression and optimal timing of conception. Intrapartum LT is only rarely performed as the outcome is commonly dismal for the mother or more commonly the fetus. On the other hand, the outcomes of pregnancy in LT recipients are favorable, and children born to LT recipients are relatively healthy. Counseling on pregnancy should start before LT and continue after LT up until pregnancy, while all pregnant LT recipients must be managed by amultidisciplinary team, including both an obstetrician and a transplant hepatologist. Additionally, an interval of at least 1-2 years after successful LT is recommended before considering pregnancy. Pregnancy-induced hypertension, pre-eclampsia, and gestational diabetes mellitus are reported more commonly during the pregnancies of LT recipients than in the pregnancies of non-transplant patients. As adverse fetal outcomes, such asmiscarriage, abortion, stillbirth, or ectopic pregnancy, may occur more often than in the non-transplant population, early planning or delivery either through a planned induction of labor or cesarean section is critical to minimize the risk of complications. No significant long-term physical or phycological abnormalities have been reported in children born to LT recipients. 相似文献
995.
996.
Spyridon Karras Cedric Annweiler Dimitris Kiortsis Ioannis Koutelidakis Kalliopi Kotsa 《Nutrients》2020,12(11)
We have previously described increased fasting plasma glucose levels in patients with normocalcemic primary hyperparathyroidism (NPHPT) and co-existing prediabetes, compared to prediabetes per se. This study evaluated the effect of parathyroidectomy (PTx) (Group A), versus conservative follow-up (Group B), in a small cohort of patients with co-existing NPHPT and prediabetes. Sixteen patients were categorized in each group. Glycemic parameters (levels of fasting glucose (fGlu), glycosylated hemoglobin (HbA1c), and fasting insulin (fIns)), the homeostasis model assessment for estimating insulin secretion (HOMA-B) and resistance (HOMA-IR), and a 75-g oral glucose tolerance test were evaluated at baseline and after 32 weeks for both groups. Measurements at baseline were not significantly different between Groups A and B, respectively: fGlu (119.4 ± 2.8 vs. 118.2 ± 1.8 mg/dL, p = 0.451), HbA1c (5.84 ± 0.3 %vs. 5.86 ± 0.4%, p = 0.411), HOMA-IR (3.1 ± 1.2 vs. 2.9 ± 0.2, p = 0.213), HOMA-B (112.9 ± 31.8 vs. 116.9 ± 21.0%, p = 0.312), fIns (11.0 ± 2.3 vs. 12.8 ± 1.4 μIU/mL, p = 0.731), and 2-h post-load glucose concentrations (163.2 ± 3.2 vs. 167.2 ± 3.2 mg/dL, p = 0.371). fGlu levels demonstrated a positive correlation with PTH concentrations for both groups (Group A, rho = 0.374, p = 0.005, and Group B, rho = 0.359, p = 0.008). At the end of follow-up, Group A demonstrated significant improvements after PTx compared to the baseline: fGlu ((119.4 ± 2.8 vs. 111.2 ± 1.9 mg/dL, p = 0.021) (−8.2 ± 0.6 mg/dL)), and 2-h post-load glucose concentrations ((163.2 ± 3.2 vs. 144.4 ± 3.2 mg/dL, p = 0.041), (−18.8 ± 0.3 mg/dL)). For Group B, results demonstrated non-significant differences: fGlu ((118.2 ± 1.8 vs. 117.6 ± 2.3 mg/dL, p = 0.031), (−0.6 ± 0.2 mg/dL)), and 2-h post-load glucose concentrations ((167.2 ± 2.7 vs. 176.2 ± 3.2 mg/dL, p = 0.781), (+9.0 ± 0.8 mg/dL)). We conclude that PTx for individuals with NPHPT and prediabetes may improve their glucose homeostasis when compared with conservative follow-up, after 8 months of follow-up. 相似文献
997.
998.
999.
1000.
Ioannis Skarmoutsos Athanasios Skarmoutsos Ioannis Katafigiotis Elisavet Tataki Athina Giagini Ioannis Adamakis Christos Alamanis Mordechai Duvdevani Nikolaos Sitaras Constantinos Constantinides 《Medical oncology (Northwood, London, England)》2018,35(7):97
The goal of the study is to examine the possible use of HA (hyaluronic acid) and HAase (hyaluronidase) as novel urine biomarkers for the early diagnosis for prostate cancer (Pca). After a prostatic massage, the urine of 118 high-risk patients for Pca was collected, and the patients were submitted to ultrasound-guided transrectal biopsy. HA and HAase were detected and analyzed with Enzyme-Linked Immunosorbent Assay, and a statistical analysis of the urine levels of the two biomarkers according to the histology results was performed. HAase and HA were independently associated with Pca, and both HAase and HA showed significant predictive ability for prostate cancer. With an optimal cut-off point of 183.71 HAase had 70% sensitivity maintaining at the same time a 55.2% specificity, while the optimal cut-off point for HA was 50.13 with 65% sensitivity and 53.9% specificity. Patients with HAase more than 183.71 ng/ml had 3.67 times greater likelihood for prostate cancer and Patients with HA more than 50.13 ng/ml had 2.31 times greater likelihood for prostate cancer. The need of novel biomarkers that will improve the efficacy of PSA is urgent. HAase and HA showed significant predictive ability for prostate cancer and were independently associated with Pca, and greater levels were associated with greater odds for prostate cancer. To Our Knowledge, this is the first study referring to the detection of HAase and HA as potential urine biomarkers for the early diagnosis of Pca. 相似文献