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Background: Endogenous cannabinoids such as anandamide and 2‐arachidonoylglycerol (2‐AG) exert important regulatory influences on neuronal signaling, participate in short‐ and long‐term forms of neuroplasticity, and modulate stress responses and affective behavior in part through the modulation of neurotransmission in the amygdala. Alcohol consumption alters brain endocannabinoid levels, and alcohol dependence is associated with dysregulated amygdalar function, stress responsivity, and affective control. Methods: The consequence of long‐term alcohol consumption on the expression of genes related to endocannabinoid signaling was investigated using quantitative RT‐PCR analyses of amygdala tissue. Two groups of ethanol (EtOH)‐exposed rats were generated by maintenance on an EtOH liquid diet (10%): the first group received continuous access to EtOH for 15 days, whereas the second group was given intermittent access to the EtOH diet (5 d/wk for 3 weeks). Control subjects were maintained on an isocaloric EtOH‐free liquid diet. To provide an initial profile of acute withdrawal, amygdala tissue was harvested following either 6 or 24 hours of EtOH withdrawal. Results: Acute EtOH withdrawal was associated with significant changes in mRNA expression for various components of the endogenous cannabinoid system in the amygdala. Specifically, reductions in mRNA expression for the primary clearance routes for anandamide and 2‐AG (fatty acid amide hydrolase [FAAH] and monoacylglycerol lipase [MAGL], respectively) were evident, as were reductions in mRNA expression for CB1, CB2, and GPR55 receptors. Although similar alterations in FAAH mRNA were evident following either continuous or intermittent EtOH exposure, alterations in MAGL and cannabinoid receptor‐related mRNA (e.g., CB1, CB2, GPR55) were more pronounced following intermittent exposure. In general, greater withdrawal‐associated deficits in mRNA expression were evident following 24 versus 6 hours of withdrawal. No significant changes in mRNA expression for enzymes involved in 2‐AG biosynthesis (e.g., diacylglicerol lipase‐α/β) were found in any condition. Conclusions: These findings suggest that EtOH dependence and withdrawal are associated with dysregulated endocannabinoid signaling in the amygdala. These alterations may contribute to withdrawal‐related dysregulation of amygdalar neurotransmission.  相似文献   
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Aging has been shown to disrupt performance on tasks that require intact visual search and discrimination abilities in human studies. The goal of the present study was to determine if canines show age-related decline in their ability to perform a novel simultaneous visual search task. Three groups of canines were included: a young group (N = 10; 3 to 4.5 years), an old group (N = 10; 8 to 9.5 years), and a senior group (N = 8; 11 to 15.3 years). Subjects were first tested for their ability to learn a simple two-choice discrimination task, followed by the visual search task. Attentional demands in the task were manipulated by varying the number of distracter items; dogs received an equal number of trials with either zero, one, two, or three distracters. Performance on the two-choice discrimination task varied with age, with senior canines making significantly more errors than the young. Performance accuracy on the visual search task also varied with age; senior animals were significantly impaired compared to both the young and old, and old canines were intermediate in performance between young and senior. Accuracy decreased significantly with added distracters in all age groups. These results suggest that aging impairs the ability of canines to discriminate between task-relevant and -irrelevant stimuli. This is likely to be derived from impairments in cognitive domains such as visual memory and learning and selective attention.  相似文献   
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Much attention has been directed toward lifestyle modifications as effective means of reducing cardiovascular disease risk. In particular, physical activity has been heavily studied because of its well-known effects on metabolic syndrome, insulin sensitivity, cardiovascular disease risk, and all-cause mortality. However, data regarding the effects of exercise on various stages of the atherosclerosis pathway remain conflicting. The investigators review previously published reports for recent observational and interventional trials investigating the effects of physical activity on markers of (or causal factors for) atherosclerotic burden and vascular disease, including serum lipoproteins, systemic inflammation, thrombosis, coronary artery calcium, and carotid intima-media thickness. In conclusion, the data show a correlation between physical activity and triglyceride reduction, apolipoprotein B reduction, high-density lipoprotein increase, change in low-density lipoprotein particle size, increase in tissue plasminogen activator activity, and decrease in coronary artery calcium. Further research is needed to elucidate the effect of physical activity on inflammatory markers and intima-media thickness.  相似文献   
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The purpose of craniomaxillofacial surgery is to improve function, occlusion, craniofacial balance, and aesthetics. Accurate diagnosis, assessment, and careful treatment planning are essential in achieving a successful outcome, and an understanding of the pattern of facial growth is integral in this process. Patients with craniofacial congenital dysmorphologies, posttraumatic asymmetries, or disturbances of facial balance from radiation may have functional and/or aesthetic issues that require treatment. Understanding the complexities of growth in the skull and face is a key component to appropriate treatment planning for these disorders. This article reviews growth and development in the craniofacial skeleton.  相似文献   
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Introduction and objectives

To investigate the relationship between inflammatory and apoptotic parameters and the severity and extent of target organ damage in patients with essential hypertension.

Methods

We studied 159 consecutive patients with treated essential hypertension. An exhaustive evaluation of damage to heart, kidney, and blood vessels was performed and plasma levels of inflammatory (interleukin 6 and soluble receptor of tumor necrosis factor-alpha type 2) and apoptotic markers (soluble receptor of tumor necrosis factor-alpha type 1 and soluble Fas receptor) were determined. Patients were categorized into four groups: a) no organ damage (33 patients); b) 1 organ damaged (52 patients); c) 2 organs damaged (44 patients), and d) 3 organs damaged (30 patients).

Results

Serum levels of interleukin 6, soluble receptor of tumor necrosis factor-alpha type 1 and soluble receptor of tumor necrosis factor-alpha type 2 were higher in patients with target organ damage than in hypertensive patients without organ damage. Increasing levels of these molecules were progressively associated with an increase in the number of organs damaged, and the highest levels were observed in the group with damage to 3 organs (heart, kidney, and blood vessels). There were no differences in soluble Fas receptor levels between groups. Logistic regression analysis showed that age, smoking, diabetes mellitus, abdominal circumference, interleukin 6, and soluble receptor of tumor necrosis factor-alpha type 1 were independently related to the number of target organs damaged.

Conclusions

Extensive hypertensive disease with involvement of more target organs was associated with greater inflammatory and apoptotic activation in these hypertensive patients.Full English text available from:www.revespcardiol.org  相似文献   
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BackgroundCorticobasal degeneration (CBD) is a neurodegenerative, sporadic disorder of unknown cause. Few familial cases have been described.ObjectiveWe aim to characterize the clinical, imaging, pathological and genetic features of two familial cases of CBD.MethodsWe describe two first cousins with CBD associated with atypical MRI findings. We performed exome sequencing in both subjects and in an unaffected first cousin of similar age.ResultsThe cases include a 79-year-old woman and a 72-year-old man of Native American and British origin. The onset of the neurological manifestations was 74 and 68 years respectively. Both patients presented with a combination of asymmetric parkinsonism, apraxia, myoclonic tremor, cortical sensory syndrome, and gait disturbance. The female subject developed left side fixed dystonia. The manifestations were unresponsive to high doses of levodopa in both cases. Extensive bilateral T1-W hyperintensities and T2-W hypointensities in basal ganglia and thalamus were observed in the female patient; whereas these findings were more subtle in the male subject. Postmortem examination of both patients was consistent with corticobasal degeneration; the female patient had additional findings consistent with mild Alzheimer's disease. No Lewy bodies were found in either case. Exome sequencing showed mutations leading to possible structural changes in MRS2 and ZHX2 genes, which appear to have the same upstream regulator miR-4277.ConclusionsCorticobasal degeneration can have a familial presentation; the role of MRS2 and ZHX2 gene products in CBD should be further investigated.  相似文献   
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