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Individual differences in cognitive ability and social behaviour are influenced by the variability in the structure and function of the limbic system. A strong heritability of the limbic cortex has been previously reported, but little is known about how genetic factors influence specific limbic networks. We used diffusion tensor imaging tractography to investigate heritability of different limbic tracts in 52 monozygotic and 34 dizygotic healthy adult twins. We explored the connections that contribute to the activity of three distinct functional limbic networks, namely the dorsal cingulum (‘medial default-mode network’), the ventral cingulum and the fornix (‘hippocampal-diencephalic-retrosplenial network’) and the uncinate fasciculus (‘temporo-amygdala-orbitofrontal network’). Genetic and environmental variances were mapped for multiple tract-specific measures that reflect different aspects of the underlying anatomy. We report the highest heritability for the uncinate fasciculus, a tract that underpins emotion processing, semantic cognition, and social behaviour. High to moderate genetic and shared environmental effects were found for pathways important for social behaviour and memory, for example, fornix, dorsal and ventral cingulum. These findings indicate that within the limbic system inheritance of specific traits may rely on the anatomy of distinct networks and is higher for fronto-temporal pathways dedicated to complex social behaviour and emotional processing.  相似文献   
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Postural orthostatic tachycardia syndrome is characterized by orthostatic intolerance. Orthostasis (or other mild physical stress) triggers a cascade of inappropriate tachycardia, lightheadedness, palpitations, and often fainting. The underlying defect is sympathetic dysregulation of the heart, which receives its sympathetic tone from the cervical and upper thoracic sympathetic ganglia. Primary hyperhidrosis is also thought to be the result of sympathetic dysregulation. We present the case of a patient treated with CT-guided, percutaneous T2 EtOH sympatholysis for craniofacial hyperhidrosis. The patient also suffered from postural orthostatic tachycardia syndrome for many years and was unresponsive to treatment. Immediately after sympatholysis, the patient experienced resolution of both craniofacial hyperhidrosis and postural orthostatic tachycardia syndrome.  相似文献   
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The diagnostic value of deoxycytidylate deaminase (dCMP) in the diagnosis of acute myocardial infarction (AMI) was examined in 31 healthy controls and 32 patients with proven AMI. Its specificity in normal controls was 93.5%. Its highest levels were measured on the 3rd to 5th post-infarct day, when its sensitivity reached 97.5%. Its diagnostic performance was similar to that of SGOT, total LDH1/LDH2 ratio greater than 1, total CPK and CPK-MB. Its peak levels showed a highly significant correlation (p less than 0.001) with those of the above enzymes. The measurement of dCMP may be a valuable complement in the diagnosis of AMI since this enzyme is not affected by lung infarction or hemolysis. Moreover, since it expresses tissue regeneration rather than destruction it may aid in the assessment of various interventions designed for the promotion of myocardial healing process.  相似文献   
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Purpose  

Our objective was to determine the efficacy and safety of image-guided, percutaneous cryoablation for American Joint Committee on Cancer pT1ANxMx and pT1BNxMx biopsy-proven renal cell carcinoma (RCC).  相似文献   
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OBJECTIVE: To investigate 24-h ambulatory blood pressure measurements (ABPM) as a tool for long-term prediction of future blood pressure (BP) status in high normal and low stage 1 hypertensives. DESIGN, SETTING AND PARTICIPANTS: A total of 165 men from a population screening program with diastolic BP (DBP) 85-94 mmHg and a systolic BP (SBP) < 150 mmHg performed a 24-h ABPM. Ten years later, 120 participants (73%) returned for renewed measurements. MAIN OUTCOME MEASURES: Blood pressure status at 10 years. RESULTS: At the 10-year follow-up, 53% of the participants were classified as hypertensive (HT) (BP > or = 140/90 or taking anti-hypertensive medication) and 47% were classified as normotensive (NT) (BP < 140/90 mmHg). There was no significant baseline differences in office SBP levels between those who were normotensive or hypertensive at follow-up (136/91 versus 138/92 mmHg), whereas both SBP and DBP night-time levels were significantly lower in the future normotensives as compared to the future hypertensives (107/69 versus 112/74 mmHg, P < 0.01). Using recommended normalcy night-time ABP levels of < 120/75 mmHg in addition to office BP (140/90) at baseline, over 85% of the subjects were correctly classified provided they met both clinic and ambulatory night-time criteria for HT and NT classification at baseline. CONCLUSION: The use of ABPM in addition to office BP's in patients with borderline hypertension greatly increases the possibility of identifying those individuals who are at a very small risk of developing future hypertension. This could potentially lead to considerable savings in both patient anxiety, physician time and resource consumption.  相似文献   
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The placenta contains several types of feto-maternal interfaces where zygote-derived cells interact with maternal cells or maternal blood for the promotion of fetal growth and viability. The genetic factors regulating the interactions between different cell types within feto-maternal interfaces and the relative contributions of the maternal and zygotic genomes are poorly understood. Genomic imprinting, the epigenetic process responsible for parental origin-dependent functional differences between homologous chromosomes, has been proposed to contribute to these events. Previous studies showed that mouse conceptuses with an absence of imprinted differences between the two copies of chromosome 12 (upon paternal inheritance of both copies) die late in gestation and have a variety of defects, including placentomegaly. Here we examined the role of chromosome 12 imprinting in these placentae in more detail. We show that the spatial interactions between different cell types within feto-maternal interfaces are defective and identify abnormal behaviors in both zygote-derived and maternal cells that are attributed to the genome of the zygote but not the mother. These include compromised invasion of the maternal decidualized endometrium and the central maternal artery situated within it by zygote-derived trophoblast, abnormalities in the wall of the central maternal artery, and defects within the zygote-derived cellular layer of the labyrinth, which is in direct contact with maternal blood. These findings demonstrate multiple roles for chromosome 12 imprinting in the placenta that have not previously been associated with imprinting effects. They provide insights into the function of imprinting in placental development and have evolutionary and clinical implications.  相似文献   
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PURPOSE: Both heart rate variability (HRV) and inflammatory markers are carrying prognostic information in coronary heart disease (CHD), however, we know of no studies examining their relation in CHD. The aim of this study, therefore, was to assess the association between HRV and inflammatory activity, as reflected by the levels of interleukin-6 (IL-6), IL-1 receptor antagonist (IL-1ra) and C-reactive protein (CRP). SUBJECTS AND METHODS: Consecutive women patients who survived hospitalization for acute myocardial infarction, and/or underwent a percutaneous transluminal coronary angioplasty or a coronary artery bypass grafting were included and evaluated in a stable condition 1 year after the index events. An ambulatory 24-h ECG was recorded during normal activities. SDNN index (mean of the standard deviations of all normal to normal intervals for all 5-min segments of the entire recording) and the following frequency domain parameters were assessed: total power, high frequency (HF) power, low frequency (LF) power and very low frequency (VLF) power. Levels of high-sensitivity CRP were measured by nephelometry, IL-6 and IL-1ra concentrations were determined by enzyme immunoassay. RESULTS: Levels of IL-6 showed an inverse relation with HRV measures even after controlling for potential confounding factors. The P-values were 0.02, 0.04, 0.01, 0.03, 0.18 for the multivariate association with SDDN index, total power, VLF power, LF power and HF power respectively. In contrast, the inverse relationship between HRV measures and CRP or IL-1ra levels were weak and nonsignificant. Correlation coefficients for the relationship between IL-6 and HRV measures were both uni- and multivariately higher than for the relationship between HRV measures and any other factors evaluated in this study. CONCLUSION: Concentration of IL-6 showed a negative, independent association with HRV in women with CHD. Thus, increased inflammatory activity, as reflected by IL-6 levels, may represent a new auxiliary mechanism linking decreased HRV to poor prognosis in CHD.  相似文献   
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