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211.
Protective effects of Ziziphora tenuior extract against chlorpyrifos induced liver and lung toxicity in rat: Mechanistic approaches in subchronic study 下载免费PDF全文
Alireza Yazdinezhad Meysam Abbasian Seyed Hojjat Hosseini Parvaneh Naserzadeh Abdol‐Hakim Agh‐Atabay Mir‐Jamal Hosseini 《Environmental toxicology》2017,32(9):2191-2202
Chlorpyrifos (CPF) is one of the most widely used organophosphorus, which has spurred renewed interest. This study was conducted to investigate the protective effect of ziziphora tenuior extract against CPF‐induced liver and lung toxicity. This study conducted 8‐week rat sub‐chronic toxicity study and then the effect of ziziphora tenuior extract in 3 different doses (40, 80, 160 mg/kg) was determined. We administrated maximum tolerated dose of CPF (6.75 mg/kg) by gavage for 8 weeks (5 times in week) to male rats. Rats were sacrificed 24 h after last dose and the biochemical analysis, which confirms involvement of oxidative stress in the pathogenesis of CPF toxicity in liver including increased in lipid peroxidation, protein carbonyl content, and ROS formation, glutathione depletion, decreased of antioxidant effect via frap oxidation and cytochrome c expulsion. In addition, pathological lesions confirm the dysfunction of the organs (liver and lung). In addition, using of ziziphora extract as an antioxidant is resulted in amelioration of oxidative stress marker in liver and lung damage. In conclusion, the current study revealed that CPF toxicity is related to oxidative stress and induction of cell death signaling and cotreatment with ziziphora extract is recommended in the routine therapy for the protection against CPF induced liver and lung tissue damage. 相似文献
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213.
EEGs of the frontal brain of patients diagnosed with major depressive disorder (MDD) have been investigated in recent years using linear methods but not based on nonlinear methods. This paper presents an investigation of the frontal brain of MDD patients using the wavelet-chaos methodology and Katz's and Higuchi's fractal dimensions (KFD and HFD) as measures of nonlinearity and complexity. EEGs of the frontal brain of healthy adults and MDD patients are decomposed into 5 EEG sub-bands employing a wavelet filter bank, and the FDs of the band-limited as well as those of their 5 sub-bands are computed. Then, using the ANOVA statistical test, HFDs and KFDs of the left and right frontal lobes in EEG full-band and sub-bands of MDD and healthy groups are compared in order to discover the FDs showing the most meaningful differences between the two groups. Finally, the discovered FDs are used as input to a classifier, enhanced probabilistic neural network (EPNN), to discriminate the MDD from healthy EEGs. The results of HFD show higher complexity of left, right and overall frontal lobes of the brain of MDD compared with non-MDD in beta and gamma sub-bands. Moreover, it is observed that HFD of the beta band is more discriminative than HFD of the gamma band for discriminating MDD and non-MDD participants, while the KFD did not show any meaningful difference. A high accuracy of 91.3% is achieved for classification of MDD and non-MDD EEGs based on HFDs of left, right, and overall frontal brain beta sub-band. The findings of this research, however, should be considered tentative because of limited data available to the authors. 相似文献
214.
Mohammad Khayatzadeh Mahani Masood Karimloo Susan Amirsalari 《Hong Kong Journal of Occupational Therapy》2011,21(1):9-14
Objective
This study aimed to investigate the effects of the Modified Adeli suit therapy (MAST) on improvement of gross motor function in children with cerebral palsy (CP).Methods
Thirty-six children with CP assigned by match pairs to three equal groups such as the MAST, the AST, and the Neurodevelopmental Treatment. They were treated for 4 weeks, 2 hr/d, 5 d/wk. All children were tested by the Gross Motor Function Measure (GMFM) at baseline, immediately before and 16 weeks after treatments.Results
All groups had improvement in the GMFM after treatment (p < .01) and there were significant differences among groups (p < .01). In the follow-up study, no significant improvement in the GMFM was seen within groups (p > .05), but again there were significant differences among groups (p < .01).Conclusion
The MAST was more effective than using either the AST or the Neurodevelopmental treatment on improvement of gross motor function in children with CP after treatment and at follow-up. 相似文献215.
216.
Parviz Daryaei Farzad Vaghef Davari Mohammadreza Mir Iraj Harirchi Hojjat Salmasian 《World journal of surgery》2009,33(4):773-777
Introduction Surgeons routinely use nasogastric (NG) tubes in most esophageal resection surgeries. Considering the numerous complications
caused by using the tube and the uncertainty about its usefulness and the scarcity of studies conducted on the subject, particularly
in patients with esophageal cancer, the necessity of using the tube in these types of cases is investigated in the present
study.
Methods In this clinical trial, patients with esophageal cancer were randomized into groups with NG tube and without NG tube after
surgery; the latter were prescribed Metoclopramide, as well. The variables recorded for each patient included the first day
of gas passage, defecation and bowel sounds (BSs) auscultation, as well as the duration of postoperative hospitalization,
nausea and vomiting, abdominal distension, pulmonary complications, wound complications, anastomosis leak, and the need for
placing/replacing the NG tube.
Results The incidence of anastomosis leak was significantly higher in the NG-tube group (6 vs. 0; P = 0.016). Other complications were not different in the two groups. The mean time of gas passage, defecation, BS auscultation,
and the duration of postoperative hospitalization did not have meaningful differences in the two groups. The need for placing/replacing
the NG tube was the same for both groups.
Conclusions The routine application of NG tubes after surgery is not recommended for all patients. We suggest that NG tubes should be
used according to the specific problems of each patient. 相似文献
217.
Ravangard R Arab M Rashidian A Akbarisari A Zare A Zeraati H 《Acta medica Iranica》2011,49(10):650-658
Survival analysis is a set of methods used for analysis of the data which exist until the occurrence of an event. This study aimed to compare the results of the use of the semi-parametric Cox model with parametric models to determine the factors influencing the length of stay of patients in the inpatient units of Women Hospital in Tehran, Iran. In this historical cohort study all 3421 charts of the patients admitted to Obstetrics, Surgery and Oncology units in 2008 were reviewed and the required patient data such as medical insurance coverage types, admission months, days and times, inpatient units, final diagnoses, the number of diagnostic tests, admission types were collected. The patient length of stay in hospital 'leading to recovery' was considered as a survival variable. To compare the semi-parametric Cox model and parametric (including exponential, Weibull, Gompertz, log-normal, log-logistic and gamma) models and find the best model fitted to studied data, Akaike's Information Criterion (AIC) and Cox-Snell residual were used. P<0.05 was considered as statistically significant. AIC and Cox-Snell residual graph showed that the gamma model had the lowest AIC (4288.598) and the closest graph to the bisector. The results of the gamma model showed that factors affecting the patient length of stay were admission day, inpatient unit, related physician specialty, emergent admission, final diagnosis and the number of laboratory tests, radiographies and sonographies (P<0.05). The results showed that the gamma model provided a better fit to the studied data than the Cox proportional hazards model. Therefore, it is better for researchers of healthcare field to consider this model in their researches about the patient length of stay (LOS) if the assumption of proportional hazards is not fulfilled. 相似文献
218.
Tissue engineering is a newly emerging biomedical technology, which aids and increases the repair and regeneration of deficient and injured tissues. It employs the principles from the fields of materials science, cell biology, transplantation, and engineering in an effort to treat or replace damaged tissues. Tissue engineering and development of complex tissues or organs, such as heart, muscle, kidney, liver, and lung, are still a distant milestone in twenty-first century. Generally, there are four main challenges in tissue engineering which need optimization. These include biomaterials, cell sources, vascularization of engineered tissues, and design of drug delivery systems. Biomaterials and cell sources should be specific for the engineering of each tissue or organ. On the other hand, angiogenesis is required not only for the treatment of a variety of ischemic conditions, but it is also a critical component of virtually all tissue-engineering strategies. Therefore, controlling the dose, location, and duration of releasing angiogenic factors via polymeric delivery systems, in order to ultimately better mimic the stem cell niche through scaffolds, will dictate the utility of a variety of biomaterials in tissue regeneration. This review focuses on the use of polymeric vehicles that are made of synthetic and/or natural biomaterials as scaffolds for three-dimensional cell cultures and for locally delivering the inductive growth factors in various formats to provide a method of controlled, localized delivery for the desired time frame and for vascularized tissue-engineering therapies. 相似文献
219.
A spatio-temporal wavelet-chaos methodology for EEG-based diagnosis of Alzheimer's disease 总被引:1,自引:0,他引:1
A spatio-temporal wavelet-chaos methodology is presented for analysis of EEGs and their delta, theta, alpha, and beta sub-bands for discovering potential markers of abnormality in Alzheimer's disease (AD). The non-linear dynamics of the EEG and EEG sub-bands are quantified in the form of the correlation dimension (CD), representing system complexity, and the largest Lyapunov exponent (LLE), representing system chaoticity. The methodology is applied to two groups of EEGs: healthy subjects and AD patients. The eyes open and eyes closed conditions are investigated to evaluate the effect of visual input and attention. EEGs from different loci in the brain are investigated to discover areas of the brain responsible for or affected by changes in CD and LLE. It is found that the wavelet-chaos methodology and the sub-band analysis developed in this research accurately characterizes the non-linear dynamics of non-stationary EEG-like signals with respect to the EEG complexity and chaoticity. It is concluded that changes in the brain dynamics are not spread out equally across the spectrum of the EEG and over the entire brain, but are localized to certain frequency bands and electrode loci. New potential markers of abnormality were discovered in this research for both eyes open and closed conditions. 相似文献