全文获取类型
收费全文 | 836篇 |
免费 | 53篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 28篇 |
妇产科学 | 26篇 |
基础医学 | 144篇 |
口腔科学 | 23篇 |
临床医学 | 99篇 |
内科学 | 199篇 |
皮肤病学 | 15篇 |
神经病学 | 64篇 |
特种医学 | 20篇 |
外科学 | 80篇 |
综合类 | 12篇 |
预防医学 | 50篇 |
眼科学 | 23篇 |
药学 | 71篇 |
中国医学 | 8篇 |
肿瘤学 | 31篇 |
出版年
2024年 | 2篇 |
2023年 | 14篇 |
2022年 | 38篇 |
2021年 | 76篇 |
2020年 | 34篇 |
2019年 | 42篇 |
2018年 | 53篇 |
2017年 | 46篇 |
2016年 | 41篇 |
2015年 | 32篇 |
2014年 | 40篇 |
2013年 | 49篇 |
2012年 | 77篇 |
2011年 | 68篇 |
2010年 | 39篇 |
2009年 | 43篇 |
2008年 | 35篇 |
2007年 | 44篇 |
2006年 | 33篇 |
2005年 | 19篇 |
2004年 | 19篇 |
2003年 | 14篇 |
2002年 | 10篇 |
2001年 | 8篇 |
2000年 | 11篇 |
1999年 | 6篇 |
1998年 | 1篇 |
1990年 | 1篇 |
1979年 | 1篇 |
排序方式: 共有896条查询结果,搜索用时 0 毫秒
81.
Koehler NK Roebbert M Dehghani K Ballmaier M Claus P von Hoersten S Shing M Odin P Strehlau J Heidenreich F 《Journal of neuroscience research》2008,86(2):392-402
In multiple sclerosis (MS) and its animal model, experimental allergic encephalomyelitis (EAE), clinical disease is associated with infiltration of the central nervous system (CNS) by immune cells. Subsequent remission with remyelination has been linked to an increased occurrence of oligodendrocyte progenitor (O2A) cells. Platelet-derived growth factor (PDGF) and fibroblast growth factor-2 (FGF-2) are key growth factors for O2A cells, yet little is known about their relevance in EAE and MS. We analyzed the expression of PDGF, FGF-2, and their receptors by peripheral-blood leukocytes (PBLs) and lymphocyte subsets during MBP-induced EAE. Strong up-regulation of PDGF, but not FGF-2, was observed in PBLs, with the highest expression after the disease maximum. T, NK, and NKT cells expressed PDGF, which is a novel observation because thus far only monocytes/macrophages have been reported to express PDGF. These results extend the idea that growth factors may contribute to improved CNS tissue repair, including PDGF, which is secreted by lesion-homing immune cells. The production of PDGF by lymphocytes may have potential therapeutic value when activating or modulating T-cell responses in demyelinating diseases. 相似文献
82.
Several neuroendocrine complications including diabetes change the morphine antinociception and the development of tolerance to the drug. Morphine antinociception was reduced significantly in morphine tolerant diabetic rats compared to the non-diabetic animals. The exact mechanism of this effect is not known. This study was performed to determine the role of nitric oxide (NO) on morphine tolerance in diabetic state. Nociceptive responses in alloxan-induced diabetic morphine tolerated rats were measured by the hot-plate test. The urinary nitric oxide level was measured spectrophotometrically with Griess reagent. For the conversion of nitrate to nitrite, vanadium chloride was used. The results showed that experimental diabetes increased morphine analgesia. Conversely, degree of tolerance to morphine was diminished in diabetic state. The urinary nitrite content in diabetic morphine tolerated rats was higher than non-diabetic groups. L-arginine significantly increased the NO production in diabetic morphine tolerated animals, whereas aminoguanidine decreased it. Appropriately, L-arginine increased the latency time of reaction to noxious stimuli in diabetic compared to non-diabetic rats. L-arginine-treated animals also showed more tolerance to morphine analgesia. As expected, aminoguanidine deducted the level of morphine tolerance in diabetic animals. It is suggested that NO has a modulatory role in the effects of diabetes on morphine analgesia and tolerance. 相似文献
83.
Mansoureh Dehghani Seyyed Morteza Hosseini Sara Molkara Danial FazilatPanah Omid Mehrpour Davood Soroosh Elham Zarei James S. Welsh Mohammad Nematshahi Seyed Alireza Javadinia 《Clinical Case Reports》2021,9(8)
Despite Radiation‐induced dermatitis is a self‐limiting complication, it can be complicated if inappropriate self‐medications have been used such as opium latex traditional extract. 相似文献
84.
Alieh Daryabor Mohammad Samadian Masoumeh Veiskarami Monireh Ahmadi Bani 《Disability and rehabilitation. Assistive technology》2017,12(4):324-332
Background: Adolescent idiopathic scoliosis (AIS) is a progressive growth disease that affects spinal anatomy, mobility, and left-right trunk symmetry. As a consequence, AIS can modify human gait. Spinal orthoses are a commonly used conservative method for the treatment of AIS.Objective: This review evaluated the AIS spinal orthosis literature that involved gait and energy consumption evaluations.Study design: Literature review.Method: According to the population intervention comparison outcome measure methods and based on selected keywords, 10 studies met the inclusion criteria.Results: People with AIS who wore a spinal orthosis, compared with able-bodied participants, walked slower with decreased hip and pelvic movements, decreased hip mediolateral forces, ground reaction force asymmetry, and excessive energy cost. Pelvis and hip frontal plane motion decreased when wearing an orthosis. Hip and pelvis movement symmetry improved when using an orthosis. Ankle and foot kinematics did not change with orthotic intervention. People with AIS continued to have excessive energy expenditure with an orthosis.Conclusion: Spinal orthoses may be considered for improving the walking style, although energy cost does not decline following the orthotic intervention.
- Implications for Rehabilitations
Problems related to scoliosis include reduced quality of life, disability, pain, postural alterations, sensory perturbations, standing instability and gait modifications.
Wearing corrective spinal orthoses in AIS subjects produce a reduction in walking speed and cadence, increase in stride length and reduction of gait load asymmetry compared to without brace condition.
Spinal orthoses do not decline excessive energy expenditure to walk versus without it.
85.
Electrical impedance tomography of human brain function using reconstruction algorithms based on the finite element method 总被引:2,自引:0,他引:2
Bagshaw AP Liston AD Bayford RH Tizzard A Gibson AP Tidswell AT Sparkes MK Dehghani H Binnie CD Holder DS 《NeuroImage》2003,20(2):752-764
Electrical impedance tomography (EIT) is a recently developed technique which enables the internal conductivity of an object to be imaged using rings of external electrodes. In a recent study, EIT during cortical evoked responses showed encouraging changes in the raw impedance measurements, but reconstructed images were noisy. A simplified reconstruction algorithm was used which modelled the head as a homogeneous sphere. In the current study, the development and validation of an improved reconstruction algorithm are described in which realistic geometry and conductivity distributions have been incorporated using the finite element method. Data from computer simulations and spherical or head-shaped saline-filled tank phantoms, in which the skull was represented by a concentric shell of plaster of Paris or a real human skull, have been reconstructed into images. There were significant improvements in image quality as a result of the incorporation of accurate geometry and extracerebral layers in the reconstruction algorithm. Image quality, assessed by blinded subjective expert observers, also improved significantly when data from the previous evoked response study were reanalysed with the new algorithm. In preliminary images collected during epileptic seizures, the new algorithm generated EIT conductivity changes which were consistent with the electrographic ictal activity. Incorporation of realistic geometry and conductivity into the reconstruction algorithm significantly improves the quality of EIT images and lends encouragement to the belief that EIT may provide a low-cost, portable functional neuroimaging system in the foreseeable future. 相似文献
86.
Novel hydrophobic cellulose aerogel (CA) supported graphene quantum dots (GQD)/Pd were synthesized with high lipophilicity, superior porosity as well as high catalytic activity. The nanocomposite aerogel was obtained in four steps, including transformation of cotton to CA, a silanization reaction of CA in the presence of TiO2 nanoparticles to give polysiloxane/TiO2 nanoparticles supported on CA (ST@CA), a modification of ST@CA with GQD to yield polysiloxane/TiO2 nanoparticles/graphene quantum dots supported on CA (STG@CA), and finally a deposition of Pd nanoparticles on STG@CA. The synthesized aerogel demonstrated hydrophobicity with a water contact angle of 136.2°. It also exhibited excellent oil/water selective absorption capacity with an oil absorption of up to 79 g g−1 with 134 g g−1 selectivity. Finally, the nanocomposite was used as a heterogeneous catalyst in the oxidation reaction of alcohols, ethylbenzene, and alkenes. High yields, excellent selectivities, green and mild reaction conditions, recyclability and biocompatibility of the catalyst were important features of the reactions.Novel hydrophobic cellulose aerogel (CA) supported graphene quantum dots (GQD)/Pd were synthesized with high lipophilicity, superior porosity as well as high catalytic activity. 相似文献
87.
Sharif-Alhoseini M Saadat S Rahimi-Movaghar A Motevalian A Amin-Esmaeili M Hefazi M Rahimi-Movaghar V 《中华创伤杂志(英文版)》2012,15(3):145-147
Objective: Injury is a major cause of morbidity and mortality in the world.The assessment of patterns and severity of injury in high-risk groups is crucial for planning and service development.On a lar... 相似文献
88.
Masoumeh Abedzadeh-Kalahroudi Mojtaba Sehat Zahra Vahedpour Parisa Talebian Akram Haghighi 《Taiwanese journal of obstetrics & gynecology》2021,60(3):458-462
ObjectiveTo evaluate the clinical characteristics and outcomes of pregnant women with Covid-19.Materials and methodsThis case series study was performed to investigate demographic, clinical and obstetric characteristics of 26 pregnant women with COVID-19 referring to a university hospital of Kashan during the epidemic of COVID-19 (March to May 2020).ResultsThe mean gestational age of the patients at admission and delivery was 31.8 ± 5.2 and 36.3 ± 3.4 weeks, respectively. The most common symptoms were fever (96.2%) followed by dyspnea and cough (30.8%). The findings of lung CT scan showed abnormalities confirming the pneumonia in 22 patients (84.6%). Cesarean section was performed in 69.2% of the mothers. The most common maternal–fetal outcome was preterm delivery (38%). Two mothers were transferred to the ICU due to deterioration in clinical condition and they underwent mechanical ventilation without any maternal death. The most common neonatal outcomes were prematurity (38%) and low birth weight (34.6%). No cases of confirmed COVID-19 were observed in the neonates.ConclusionClinical manifestations and laboratory and radiographic findings in pregnant women with COVID-19 are similar to the general population. Common outcomes of pregnancy and delivery in mothers included increased rate of preterm delivery and cesarean section. The most prevalent neonatal outcomes included prematurity and LBW. Careful monitoring of pregnant women with COVID-19 is recommended. 相似文献
89.
90.