全文获取类型
收费全文 | 4296篇 |
免费 | 181篇 |
国内免费 | 22篇 |
专业分类
耳鼻咽喉 | 217篇 |
儿科学 | 119篇 |
妇产科学 | 122篇 |
基础医学 | 504篇 |
口腔科学 | 16篇 |
临床医学 | 343篇 |
内科学 | 1216篇 |
皮肤病学 | 70篇 |
神经病学 | 364篇 |
特种医学 | 81篇 |
外科学 | 447篇 |
综合类 | 34篇 |
一般理论 | 2篇 |
预防医学 | 230篇 |
眼科学 | 122篇 |
药学 | 401篇 |
中国医学 | 2篇 |
肿瘤学 | 209篇 |
出版年
2023年 | 20篇 |
2022年 | 136篇 |
2021年 | 247篇 |
2020年 | 71篇 |
2019年 | 88篇 |
2018年 | 125篇 |
2017年 | 95篇 |
2016年 | 83篇 |
2015年 | 97篇 |
2014年 | 141篇 |
2013年 | 215篇 |
2012年 | 327篇 |
2011年 | 377篇 |
2010年 | 180篇 |
2009年 | 134篇 |
2008年 | 260篇 |
2007年 | 292篇 |
2006年 | 300篇 |
2005年 | 303篇 |
2004年 | 281篇 |
2003年 | 239篇 |
2002年 | 215篇 |
2001年 | 20篇 |
2000年 | 19篇 |
1999年 | 19篇 |
1998年 | 24篇 |
1997年 | 16篇 |
1996年 | 14篇 |
1995年 | 9篇 |
1994年 | 16篇 |
1993年 | 11篇 |
1992年 | 11篇 |
1991年 | 13篇 |
1990年 | 7篇 |
1989年 | 7篇 |
1988年 | 4篇 |
1987年 | 6篇 |
1986年 | 5篇 |
1985年 | 8篇 |
1984年 | 5篇 |
1983年 | 6篇 |
1982年 | 9篇 |
1980年 | 6篇 |
1978年 | 5篇 |
1977年 | 9篇 |
1975年 | 3篇 |
1971年 | 2篇 |
1967年 | 2篇 |
1966年 | 2篇 |
1961年 | 2篇 |
排序方式: 共有4499条查询结果,搜索用时 62 毫秒
31.
Wojciech Czogaa Magorzata Czogaa Wojciech Strojny Gracjan Wtor Pawe Wokow Magorzata Wjcik Mirosaw Bik Multanowski Przemysaw Tomasik Andrzej Wdrychowicz Wojciech Kowalczyk Karol Miklusiak Agnieszka azarczyk Przemysaw Haubiec Szymon Skocze 《Nutrients》2021,13(5)
The occurrence of childhood obesity is influenced by both genetic and epigenetic factors. FTO (FTO alpha-ketoglutarate dependent dioxygenase) is a gene of well-established connection with adiposity, while a protooncogene PLAG1 (PLAG1 zinc finger) has been only recently linked to this condition. We performed a cross-sectional study on a cohort of 16 obese (aged 6.6–17.7) and 10 healthy (aged 11.4–16.9) children. The aim was to evaluate the relationship between methylation and expression of the aforementioned genes and the presence of obesity as well as alterations in anthropometric measurements (including waist circumference (WC), body fat (BF_kg) and body fat percent (BF_%)), metabolic parameters (lipid profile, blood glucose and insulin levels, presence of insulin resistance) and blood pressure. Expression and methylation were measured in peripheral blood mononuclear cells using a microarray technique and a method based on restriction enzymes, respectively. Multiple regression models were constructed to adjust for the possible influence of age and sex on the investigated associations. We showed significantly increased expression of the FTO gene in obese children and in patients with documented insulin resistance. Higher FTO expression was also associated with an increase in WC, BF_kg, and BF_% as well as higher fasting concentration of free fatty acids (FFA). FTO methylation correlated positively with WC and BF_kg. Increase in PLAG1 expression was associated with higher BF%. Our results indicate that the FTO gene is likely to play an important role in the development of childhood adiposity together with coexisting impairment of glucose-lipid metabolism. 相似文献
32.
Grzegorz Kowalski Marcin Zawadzki Wojciech Leppert Paweł Szpot Marta Siczek Krzysztof Słowiński Małgorzata Sobieszczańska Agata Gawłowska Katarzyna Wieczorowska-Tobis 《Burns : journal of the International Society for Burn Injuries》2021,47(4):880-887
BackgroundThe aim of this study was to assess the analgesic efficacy of sufentanil in dressings after surgical treatment of burn wounds.Patients and methodsTwenty adult patients, who underwent surgical treatment of third–degree burn wounds under general anesthesia, were included. Two of the patients underwent surgery twice. During surgery, patients received 50–100 μg fentanyl every 20–30 min and, after surgery, patients received 100 mg ketoprofen twice daily. Additionally, ten patients (group 1) received 50 μg sufentanil added to the burn wound dressings soaked in octenidine and phenoxyethanol while 10 patients (group 2) received 25 μg sufentanil added to the same dressings. The rescue analgesic, which was administered when pain intensified, was 5 mg subcutaneous morphine. Plasma sufentanil concentrations were assayed at 1, 2, 3, and 6 h after surgery completion and when pain was reported, along with pain intensity evaluation.ResultsSufentanil was not detected in the serum of any patients. Rescue morphine was given during the postoperative period (24 h) in one patient in group 1 (who underwent surgery twice) and three patients in group 2. The mean sufentanil concentration in dressings was higher in group 1 (0.13 ± 0.03) than group 2 (0.06 ± 0.03 μg/mL; p < 0.001). The group 1 patient who received rescue morphine had a sufentanil concentration of 0.10 μg/mL, which was the lowest concentration in group 1. Group 2 patients who received rescue morphine had sufentanil concentrations of at least two–fold lower (0.03–0.05 μg/mL). No adverse effects were observed.ConclusionsSufentanil in dressings after burn wound surgery provides effective and safe analgesia and the sufentanil concentration in dressings should be ≥0.10 μg/mL in a solution of octenidine and phenoxyethanol. 相似文献
33.
34.
Isabel M. A. Brüggenwirth Maureen J. M. Werner René Adam Wojciech G. Polak Vincent Karam Michael A. Heneghan Arianeb Mehrabi Jürgen L. Klempnauer Andreas Paul Darius F. Mirza Johann Pratschke Mauro Salizzoni Daniel Cherqui Michael Allison Olivier Soubrane Steven J. Staffa David Zurakowski Robert J. Porte Vincent E. de Meijer all the other contributing centers the European Liver Intestine Transplant Association 《Transplant international》2021,34(10):1928-1937
High-risk combinations of recipient and graft characteristics are poorly defined for liver retransplantation (reLT) in the current era. We aimed to develop a risk model for survival after reLT using data from the European Liver Transplantation Registry, followed by internal and external validation. From 2006 to 2016, 85 067 liver transplants were recorded, including 5581 reLTs (6.6%). The final model included seven predictors of graft survival: recipient age, model for end-stage liver disease score, indication for reLT, recipient hospitalization, time between primary liver transplantation and reLT, donor age, and cold ischemia time. By assigning points to each variable in proportion to their hazard ratio, a simplified risk score was created ranging 0–10. Low-risk (0–3), medium-risk (4–5), and high-risk (6–10) groups were identified with significantly different 5-year survival rates ranging 56.9% (95% CI 52.8–60.7%), 46.3% (95% CI 41.1–51.4%), and 32.1% (95% CI 23.5–41.0%), respectively (P < 0.001). External validation showed that the expected survival rates were closely aligned with the observed mortality probabilities. The Retransplantation Risk Score identifies high-risk combinations of recipient- and graft-related factors prognostic for long-term graft survival after reLT. This tool may serve as a guidance for clinical decision-making on liver acceptance for reLT. 相似文献
35.
Dimitri Sneiders Anne-Baue R. M. van Dijk Wojciech G. Polak Darius F. Mirza M. Thamara P. R. Perera Hermien Hartog 《Transplant international》2021,34(12):2534-2546
Full-left-full-right split liver transplantation (FSLT) for adult recipients, may increase the availability of liver grafts, reduce waitlist time, and benefit recipients with below-average body weight. However, FSLT may lead to impaired graft and patient survival. This study aims to assess outcomes after FSLT. Five databases were searched to identify studies concerning FSLT. Incidences of complications, graft- and patient survival were assessed. Discrete data were pooled with random-effect models. Graft and patient survival after FSLT were compared with whole liver transplantation (WLT) according to the inverse variance method. Vascular complications were reported in 25/273 patients after FSLT (Pooled proportion: 6.9%, 95%CI: 3.1–10.7%, I2: 36%). Biliary complications were reported in 84/308 patients after FSLT (Pooled proportion: 25.6%, 95%CI: 19–32%, I2: 44%). Pooled proportions of graft and patient survival after 3 years follow-up were 72.8% (95%CI: 67.2–78.5, n = 231) and 77.3% (95%CI: 66.7–85.8, n = 331), respectively. Compared with WLT, FSLT was associated with increased graft loss (pooled HR: 2.12, 95%CI: 1.24–3.61, P = 0.006, n = 189) and patient mortality (pooled HR: 1.81, 95%CI: 1.17–2.81, P = 0.008, n = 289). FSLT was associated with high incidences of vascular and biliary complications. Nevertheless, long-term patient and graft survival appear acceptable and justify transplant benefit in selected patients. 相似文献
36.
Elżbieta Tabor Hanna Hűpsch Joanna Rokicka Teresa Sierpińska Jerzy Konstantynowicz Karolina Orywal Wojciech Pluskiewicz 《Journal of clinical densitometry》2021,24(1):14-21
Aim: The aim of the study was to investigate whether salivary mineral content may be associated with bone status in women after menopause. Material and methods: The study group consisted of 125 postmenopausal women aged 64.3 ± 6.9 yr, derived from the epidemiological SilesiaOsteoActive Study. All participants underwent hip and spine bone densitometry using dual energy X-ray absorptiometry, dental examination, and saliva content analysis. Data for salivary pH, copper, calcium, phosphorus, and zinc concentrations were evaluated. Results: Mean femoral neck bone mineral density (BMD) was 0.739 ± 0.118 g/cm2, total hip BMD 0.891 ± 0.14 g/cm2, and spine BMD 0.868 ± 0.14 g/cm2. Salivary pH was significantly lower in women with spinal osteoporosis defined as T-score below ?2.5, compared to individuals with normal BMD (pH: 6.65 ± 0.67 vs 6.96 ± 0.58, p < 0.05). There was a significant though weak inverse correlation between Ca concentration in saliva and femoral neck BMD (r = ?0.23, p < 0.05). Conclusions: High salivary calcium content and low salivary pH may be indicative of low hip and decreased spine BMD, respectively. These associations may reflect demineralization process (calcium redistribution) influencing bone, and a negative effect of acidity on mineral tissues, although causal pathway remains not clear. 相似文献
37.
Agata Kurzyk Tomasz Dębski Wojciech Święszkowski Zygmunt Pojda 《Journal of biomaterials science. Polymer edition》2019,30(5):376-397
Adipose tissue yields adult adipose stem cells (ASCs) in large quantities via less-invasive methods. These cells are of interest owing to their modulating properties and paracrine activities, which can be harnessed in regenerative medicine. Many studies on the use of rat fat tissue in an autologous animal model have been conducted; however, the different locations to obtain stromal vascular fraction of rat fat depots have not been fully characterized. The purpose of the current study was to identify optimal source of ASC from various locations of rat body. Animal experiments in vitro revealed that fat depots from cervical fat are an optimal ASC source. A high ASC yield facilitates subsequent studies on autologous transplantation in rats. The secondary objective was to compare the efficiency of osteoinductive media composition and evaluate of osteogenic potential of ASCs for seeding on scaffolds for bone repair. Scaffolds were assessed in vitro, using rat adipose stem cells and three-dimensional (3D) scaffolds comprising polycaprolactone (PCL) or polycaprolactone covered with tricalcium phosphate (PCL + 5%TCP). Seeded ASCs adhere to the surface and migrate to the scaffolds. Upon staining and determining alkaline phosphatase levels, PCL + 5%TCP scaffolds performed better than PCL scaffolds. Furthermore, growth factors such as BMP2 and FGF2 significantly increased ASC mineralization and induced osteogenesis (p?<?0.05). Our results may help select and develop pre-clinical animal model for confirming the use of ASC, alone or in association with appropriate biomaterials for bone repair. 相似文献
38.
S Zommer-Urbańska P Topolewski P Wojciech H Bojarowicz 《Roczniki Państwowego Zak?adu Higieny》1991,42(1):25-32
Fluorine and lead were determined by spectroscopic methods in some vegetables harvested in 1988 in two groups of Employees' Gardens in Inowroc?aw ("Transportowiec" and "Irena", distant from the Household Glassworks "Irena" by ca. 500 and 2600 m, respectively). Employees' Gardens "Irena" were divided into 2 belts, in consideration of a vicinal traffic artery. It was found that 42% of the plants harvested in Employees' Gardens "Transportowiec" exhibited excessive contents of fluorine, and 91%--of lead; fluorine contamination of vegetables was, however, slight, except for parsley leaves containing 56.0 mg F per 1 kg dry weight. In the case of Employees' Gardens "Irena", in the I belt (30-40 m from the traffic artery) the level of fluorine was excessive in 8.3% of plants, and that of lead--in 63.6% of plants; in the II belt (80-100 m from the traffic artery) the respective values were 17% for fluorine and 66.6% for lead. 相似文献
39.
The effects of acamprosate and neramexane on cue-induced reinstatement of ethanol-seeking behavior in rat. 总被引:4,自引:0,他引:4
Daniel Bachteler Daina Economidou Wojciech Danysz Roberto Ciccocioppo Rainer Spanagel 《Neuropsychopharmacology》2005,30(6):1104-1110
This study examines, for the first time, the effects of acamprosate and the non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist neramexane on ethanol-seeking induced by alcohol-related environmental stimuli in an animal model of relapse. Wistar rats were trained to operantly self-administer ethanol (10% w/v) or water on a fixed-ratio 1 schedule in a 30-min daily session. Ethanol availability was signaled by an olfactory discriminative stimulus of orange extract (S+). In addition, each lever press was accompanied by a 5-s illumination of the operant chamber's house light (CS+). Water availability was signaled by anise odor (S-) and 5-s white noise stimulus (CS-). After completion of the conditioning phase, indicated by stable levels of responding, operant behaviors were extinguished. Prior to reinstatement tests, animals were divided into groups according to either treatment with acamprosate (100, 200 mg/kg given twice), neramexane (1.0, 2.0, 4.0 mg/kg), or vehicle. In vehicle-treated rats, re-exposure to the S+/CS+ in the absence of further ethanol availability elicited strong recovery of responding. No effect was observed following presentation of water-paired cues (S-/CS-). Acamprosate dose-dependently attenuated recovery of responding elicited by ethanol-paired cues (S+/CS+), whereas responding under S-/CS- was not modified by drug administration. Treatment with 1.0 and 2.0 mg/kg of neramexane did not significantly modify responding under both S+/CS+ and S-/CS- conditions. However, a slight reduction of cue-induced reinstatement of alcohol seeking was observed. At the dose of 4.0 mg/kg, neramexane elicited a marked inhibition of responding following presentation of both ethanol- and water-paired cues. In conclusion, acamprosate significantly and selectively reduced alcohol-seeking elicited by environmental stimuli predictive of alcohol availability. Treatment with neramexane that shares part of the pharmacological effects of acamprosate on NMDA receptors, however, resulted in a nonselective reduction of lever responding. 相似文献
40.
The involvement of glutamate mediated neurotoxicity in the pathogenesis of Alzheimer's disease is finding increasingly more acceptance in the scientific community. Central to this hypothesis is the assumption that in particular glutamate receptors of the N-methyl-D-aspartate (NMDA) type are overactivated in a tonic rather than a phasic manner. Such continuous mild activation leads under chronic conditions to neuronal damage. Moreover, one should consider that impairment of plasticity (learning) may result not only from neuronal damage per se but also from continuous activation of NMDA receptors. To investigate this possibility we tested whether overactivation of NMDA receptors using either non-toxic doses/concentrations of a direct NMDA agonist or through an indirect approach--decrease in magnesium concentration--produces deficits in plasticity. In fact NMDA both in vivo (passive avoidance test) and in vitro (LTP in CA1 region) impaired learning and synaptic plasticity. Under these conditions memantine which is an uncompetitive NMDA receptor antagonist with features of "improved magnesium" (voltage dependence, affinity) attenuated the deficit. The more direct proof that memantine can act as a surrogate for magnesium was obtained in LTP experiments under low magnesium conditions. In this case as well, impaired LTP was restored in the presence of therapeutically relevant concentrations of memantine (1 microM). In vivo, doses leading to similar brain/serum levels produce neuroprotection in animal models relevant for neurodegeneration in Alzheimer's disease such as neurotoxicity produced by inflammation in the NBM or beta-amyloid injection to the hippocampus. Hence, we postulate that if in Alzheimer's disease overactivation of NMDA receptors occurs indeed, memantine would be expected to improve both symptoms (cognition) and slow down disease progression because it takes over the physiological function of magnesium. 相似文献