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101.
Summary: Purpose : We studied the functional organization of the interictal epileptic spike complex in patients with benign rolandic epilepsy of childhood (BREC).
Methods : We recorded interictal epileptiform spikes and somatosensory evoked potentials after median nerve stimulation, providing a biologic marker for the location of the central sulcus in 12 patients with BREC. We used multiple dipole modeling to assess the number, the three-dimensional intracerebral location, and the time activity of the underlying neuronal sources.
Results : Although the interictal spike complex could be modeled by a single tangential dipolar source in seven patients (group 1), in the remaining five patients, two sources—a radial and a tangential dipole—were necessary adequately to explain the interictal spikes (group 2). The tangential source was located deeper than the radial source and was characterized by a frontal positivity and a centroparietal negativity with a phase reversal across the central sulcus, suggesting that the interictal spikes originated in the anterior wall of the central sulcus. The radial source showed a single electronegativity over the ipsilateral central region, which would be compatible with involvement of the top of either the pre- or postcentral gyrus. Both sources showed biphasic time patterns with an average latency difference of 30 ms.
Conclusions : Our results indicate that in some patients with typical BREC, the interictal epileptiform spike complex is generated by multiple, simultaneously active neuronal populations within the central region and that epileptiform activity is propagated between these two adjacent cortical areas.  相似文献   
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103.
Synchronous firing of spatially separate neurons was studied with multi-electrode recordings in area 17 of the visual cortex of strabismic cats which had developed behaviourally verified amblyopia of the deviated eye. Responses of neurons were evoked with moving light bars or gratings of different spatial frequency. Neurons driven by the normal eye displayed stronger synchronization of their responses than neurons dominated by the amblyopic eye. These interocular differences were highly significant and particularly pronounced for grating stimuli of high spatial frequency. No interocular differences were noted with respect to the amplitudes of responses to the light bars and gratings. These results suggest reduced synchronization of population responses as a neurophysiological correlate of strabismic amblyopia and underline the importance of correlated firing of spatially separate cortical neurons for normal processing of visual information.  相似文献   
104.
Objectives:  The present study in hypomanic and manic patients explored how amygdala responses to affective stimuli depend on the valence of the stimuli presented.
Methods:  We compared 10 patients with 10 matched healthy control subjects. We measured blood oxygen level-dependent (BOLD) responses in the amygdala while subjects passively viewed photographs taken from the International Affective Picture System. After the fMRI session, subjects saw the pictures again and subjectively rated the emotional valence and intensity of each picture.
Results:  Compared to healthy individuals, hypomanic or manic patients showed higher valence ratings in positive pictures and associated larger BOLD responses in the left amygdala during positive versus neutral picture viewing. This enhanced amygdala activation was correlated with Young Mania Rating Scale scores and with euphoric as opposed to irritable symptom presentation.
Conclusions:  Increased valence ratings and amygdala responses to positive affective stimuli may reflect a positive processing bias contributing to elevated mood states characteristic for euphoric mania.  相似文献   
105.
Chronic lymphocytic leukaemia (CLL) is the most common leukaemia in the Western world. Historically, CLL patients have received prednisone- or chlorambucil-containing regimens, resulting in modest responses and a slim chance of long-term survival. The addition of purine nucleoside analogues, specifically fludarabine, to the armamentarium has significantly improved efficacy in treatment-naive or heavily pretreated CLL patients. Since the 1980s, fludarabine monotherapy has demonstrated an improvement in response over historical chemotherapeutic agents. Single-agent fludarabine therapy has expanded into a combination regimen containing cyclophosphamide and has further evolved to incorporate monoclonal antibodies. A review of the fludarabine literature shows that these advancements in fludarabine-containing therapy have enhanced the overall patient response with a potential increase in survival time, thus representing progress towards a superior treatment for CLL.  相似文献   
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108.
We examined 38 patients out of 41 with indicis tendon transfer, performed at the Department for Hand Surgery of the University of Munich during the past eight years; the patients had suffered a subcutaneous rupture or an open traumatic separaton of the extensor pollicis longus tendon. In five cases the function fo the operated had was found deteriorated by other causes. Of the remaining 33 patients 26 showed an excellent function and five patients a good function of the operated thumb. Deficient functional results were discovered with two patients. Almost in all cases extension of the index finger was found reduced in force; none of the patients, however become aware of it. In performing the tendon anastomosis care must be taken to apply proper tensions to the tendons joined.  相似文献   
109.
The individual risk of infection and requirements for medical treatment after high-dose chemotherapy have been unpredictable. In this prospective, multicenter, open-label study we investigated the potential of granulocyte colony-stimulating factor (G-CSF) responsiveness as a predictor. A total of 168 patients with multiple myeloma or lymphoma received a single dose of subcutaneous G-CSF (lenograstim, 263 μg) after high-dose chemotherapy. Highly variable leukocyte peaks were measured and grouped as low (quartile 1; leukocytes 100-10 100/μL), medium (quartile 2; leukocytes > 10 100-18 300/μL), and high (quartiles 3/4; leukocytes > 18 300-44 800/μL). G-CSF responsiveness (low vs medium vs high) was inversely correlated with febrile neutropenia (77% vs 60% vs 48%; P = .0037); the rate of infection, including fever of unknown origin (91% vs 67% vs 54%; P < .0001); days with intravenous antibiotics (9 vs 6 vs 5; P < .0001); and antifungal therapy (P = .042). In multivariate analysis, G-CSF responsiveness remained the only factor significantly associated with infection (P = .016). In addition, G-CSF responsiveness was inversely correlated with grade 3/4 oral mucositis (67% vs 33% vs 23%; P < .0001). G-CSF responsiveness appears as a signature of the myeloid marrow reserve predicting defense against neutropenic infection after intensive chemotherapy. This study is registered at http://www.clinicaltrials.gov as NCT01085058.  相似文献   
110.
Background:  Adiponectin is a circulating protein with hepatoprotective effects.
Aims:  To study the relationship of excessive alcohol consumption and serum adiponectin levels (SAL).
Patients and Methods:  The SAL were determined in (i) heavy drinkers without advanced liver damage during the course of alcohol withdrawal, (ii) patients with chronic hepatitis C virus (HCV) infection, (iii) patients with alcohol-associated cirrhosis, and (iv) healthy volunteers that consumed excessive amounts of alcohol for only a short period of time. Further, primary human hepatocytes (PHH) and adipocytes were incubated in vitro with alcohol or serum of patients.
Results:  Patients with chronic alcohol consumption had significantly higher SAL than HCV-patients with comparable degrees of liver damage. In alcoholics, but not in HCV patients, SAL positively correlated with serum levels of aminotransferases. Further, SAL correlated with the amount of alcohol consumption but declined during the course of alcohol abstinence. After short-term excessive alcohol consumption SAL were not elevated in healthy individuals. Adiponectin mRNA was detectable in adipocytes but not in hepatocytes, and alcohol failed to induce adiponectin in both cell types. In contrast, serum of active drinkers induced adiponectin expression in adipocytes while serum from the same individuals collected after alcohol withdrawal had no effect.
Conclusions:  Alcohol exhibits a specific effect on SAL that is dose and time dependent, and correlates with the degree of hepatic damage. Alcohol does not seem to affect adiponectin expression directly in adipocytes but potentially via mediators systemically released as a result of the chronic alcohol intake.  相似文献   
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