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1.
It is widely held that long-term memories are established by consolidation of newly acquired information into stable neural representations, a process that requires protein synthesis and synaptic plasticity. Plasticity within the nucleus accumbens (NAc), a major component of the ventral striatum, is thought to mediate instrumental learning processes and many aspects of drug addiction. Here we show that the inhibition of protein synthesis within the NAc disrupts consolidation of an appetitive instrumental learning task (lever-pressing for food) in rats. Post-trial infusions of anisomycin immediately after the first several training sessions prevented consolidation, whereas infusions delayed by 2 or 4 hours had no effect. However, if the rats were allowed to learn the task, the behavior was not sensitive to disruption by intra-accumbens anisomycin. Control infusions into the medial NAc shell or the dorsolateral striatum did not impair learning; in fact, an enhancement was observed in the latter case. These results show that de novo protein synthesis within the NAc is necessary for the consolidation, but not reconsolidation, of appetitive instrumental memories. 相似文献
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Mahmoud Hadipour Dehshal Mehdi Tabrizi Namini Alireza Ahmadvand Mohsen Manshadi Forouzan Sadeghian Varnosfaderani Hassan Abolghasemi 《Hemoglobin》2014,38(3):179-187
β-Thalassemia major (β-TM) is an inherited disease and efforts have been made in several countries to reduce the number of affected births. In the present study, we aimed to evaluate the Iranian thalassemia prevention program, considered to be an important program in the region. The time period of the present study ranges from 2007–2009, during which new thalassemic births and the relevant causes were evaluated throughout the country. A cross-sectional analytical study was conducted at the Iranian Blood Transfusion Organization (IBTO), Tehran, Iran. A questionnaire was forwarded to all blood centers of the IBTO so as to obtain information about the new cases of thalassemia and the causes of these thalassemic births. Provincial thalassemia societies also received the questionnaires so that screening and prenatal diagnosis (PND) errors would be recorded. The results showed that 755 new thalassemia cases were born during 2007–2009 with the average fall in affected thalassemia births of 80.82%. The main cause of the new births was attributed to unregistered “timeless religious marriages” based on the conventions of the Sunni community which accounted for 43.17% of all new cases mainly having occurred in Sistan & Baluchestan Province. Not using PND was evaluated to be another main cause. Although the prevention program has led to a great reduction in thalassemic births, new measures are required, including research on how to make the program compatible with social and economic conventions and norms of Sistan & Baluchestan Province. The province of Kohgiluyeh Boyer Ahmad also needs to be revisited in terms of the program efficacy. 相似文献
3.
Filippo Maria Bianchi Simone Scardapane Antonello Rizzi Aurelio Uncini Alireza Sadeghian 《Cognitive computation》2016,8(3):442-461
We propose a system able to synthesize automatically a classification model and a set of interpretable decision rules defined over a set of symbols, corresponding to frequent substructures of the input dataset. Given a preprocessing procedure which maps every input element into a fully labeled graph, the system solves the classification problem in the graph domain. The extracted rules are then able to characterize semantically the classes of the problem at hand. The structured data that we consider in this paper are images coming from classification datasets: they represent an effective proving ground for studying the ability of the system to extract interpretable classification rules. For this particular input domain, the preprocessing procedure is based on a flexible segmentation algorithm whose behavior is defined by a set of parameters. The core inference engine uses a parametric graph edit dissimilarity measure. A genetic algorithm is in charge of selecting suitable values for the parameters, in order to synthesize a classification model based on interpretable rules which maximize the generalization capability of the model. Decision rules are defined over a set of information granules in the graph domain, identified by a frequent substructures miner. We compare the system with two other state-of-the-art graph classifiers, evidencing both its main strengths and limits. 相似文献
4.
Soleimani A Salarifar M Kasaian SE Sadeghian S Nejatian M Abbasi A 《Asian cardiovascular & thoracic annals》2008,16(3):202-207
To evaluate the effects of a cardiac rehabilitation program on heart rate recovery after percutaneous transluminal coronary angioplasty, a historical cohort study was performed on 436 patients of whom 285 were grouped on completion of 5, 10, or 24 training sessions. All 3 groups showed significant improvements in heart rate recovery, peak heart rate during treadmill testing, and end-training heart rate, from baseline to follow-up. Heart rate recovery on follow-up correlated significantly with the number of completed exercise sessions. The number of sessions, baseline ejection fraction, and age were independent predictors of mean post-training heart rate recovery. The cardiac rehabilitation program had a significant effect on peak heart rate and heart rate recovery, regardless of the underlying characteristics of the patients. 相似文献
5.
Jahangir ABDI Behnaz AKHOUNDI Mehdi MOHEBALI Abolhasan GHADERIPOUR Zahra KAKOEE Faezeh NAJAFI 《Iranian Journal of Parasitology》2015,10(1):56-61
Background:
Visceral leishmaniasis (VL) as one of the most important human parasitic disease is endemic in some parts of Iran. Several cases of VL have been reported recently in the Ilam Province. The current study aimed to assess the present status of human VL in the region.Methods:
A random cluster sampling method was used to collect 456 serums samples from the children up to 12 years of age and 10% of adults living in urban and rural areas of the province. All the collected serum samples were tested by direct agglutination test (DAT) to detect anti- Leishmania infantum antibodies.Results:
Of the examined 456 serum samples with direct agglutination test (DAT), only 21 (0.43%) sera showed anti- Leishmania antibodies at titers 1:400 and higher. Distribution of anti- Leishmania antibodies titers were: 1:400(n=4), 1:800(n=11), 1:1600(n=3), 1:3200(n=1), and 1:6400(n=1). Individuals with titers ≥1:3200 showed clinical signs and symptoms such as fever and splenomegaly. The highest and lowest seropositivity were observed in the age groups of 5–9 and >15 years old, respectively. There were no significant difference between the rate of seropositivity in males and females.Conclusion:
VL with a low prevalence circulates in some parts of Ilam province, particularly in the southern parts. Complementary studies should be needed to find animal reservoir hosts and vectors. Furthermore, health systems and physicians should pay particular attention to the disease. 相似文献6.
Shirvani Hossein Rostamkhani Fatemeh Arabzadeh Ehsan Mohammadi Faezeh Mohammadi Fatemeh 《Sport Sciences for Health》2021,17(4):849-854
Sport Sciences for Health - The widespread prevalence and mortality of coronavirus diseases-2019 (COVID-19) lead many researchers to study the SARS-CoV-s2 infection to find a treatment for this... 相似文献
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Vahid Farnia Jalal Shakeri Faezeh Tatari Toraj Ahmadi Juibari Katayoun Yazdchi Hafez Bajoghli 《The American journal of drug and alcohol abuse》2014,40(1):10-15
Background: Lifetime prevalence of amphetamine-induced psychotic disorder is reported as being up to 23% for methamphetamine (MA) abusers. Approximately 25% of those with a baseline DSM-IV diagnosis of substance-induced psychosis are diagnosed with primary psychosis at one-year follow-up. Evidence on the treatment of amphetamine psychosis is very limited. Objectives: To investigate the efficacy of risperidone versus aripiprazole in treatment of amphetamine-induced psychotic symptoms. Methods: In a double-blind study, 45 participants were randomly allocated to either aripiprazole 15?mg or risperidone 4?mg daily over a six-week trial. Positive and negative symptoms of psychosis were assessed using the Scale for Assessment of Negative Symptoms (SANS) and the Scale for Assessment of Positive Symptoms (SAPS) at baseline and completion of the trial. Results: SANS and SAPS scores decreased significantly in both groups. Mean SAPS score reduction in risperidone and aripiprazole group was 16.20 and 10.80, respectively, after trial course (p?0.001). Mean SANS score reduction in risperidone and aripiprazole group was 9.35 and 11.25, respectively (p?=?0.08). Conclusions: Both aripiprazole and risperidone were effective for patients diagnosed with amphetamine-induced psychotic disorder. However, risperidone had the greater effect on positive psychotic symptoms while patients with negative symptoms may respond better to aripiprazole. There is a case for further studies evaluating the efficacy of atypical antipsychotics in this disorder. 相似文献
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