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EMG responses in the external anal sphincter (EAS), the rectus abdominis muscle (RA), and the anterior tibial muscle (TA) were recorded following single magnetic transcranial cortical stimulations (TCCS) in seven healthy volunteers. The responses in the EAS differed from the responses in the other muscles. They had comparatively long durations ranging from 1 to 2 seconds, no inhibitory periods were observed, and there was no tendency for habituation to occur following a limited number of stimuli. The responses recorded in the EAS were used as test responses in order to evaluate the excitability changes in the EAS motoneurons occurring during bladder filling. Cystometries with filling rates of 15, 50 and 200 ml/min were done. During these cystometries TCCS were applied repeatedly, with constant strength, after each 50 ml of filling up to bladder capacity. The responses following TCCS changed in a highly reproducible way during bladder filling. After 100–200 ml of filling, the responses had longer latencies, diminished sizes, and shorter durations. When the filling reached a level 50–150 ml below capacity, the responses in most subjects again became greater and the latencies shorter. The changes were believed to be physiological. It was concluded that the EAS motoneurons are under both inhibitory and facilitatory influence during bladder filling in intact healthy humans. Facilitatory influences are often observed when the bladder is filled close to capacity. At lower bladder volumes the observed influence is always inhibitory. A decrease in the EMG activity of the EAS during filling cystometry should consequently not be regarded as a pathological response.  相似文献   
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The circulating concentration of 1,25-dihydroxycholecalciferol [1,25-(OH)2D3] is a physiologic index of enzymatic activity of the renal 1-hydroxylase of 25-hydroxychole-calciferol (25-OH-D3). Hydroxylation of 25-OH-D3 and circulating 1,25-(OH)2D3 are decreased in the streptozotocin diabetic rat. We previously found that activity of another redox enzyme system, cytosolic superoxide dismutase, also decreased in streptozotocin diabetes, can be restored by treatment with glutathione. In the present experiment we tested the effect of glutathione treatment on vitamin D metabolism in control and diabetic rats. Enteral glutathione increased circulating 1,25-(OH)2D3 and decreased 25-OH-D3 in both control and diabetic animals. These results suggest that exogenous glutathione increases 25-OH-D3 1-hydroxylation both under basal conditions in the normal animal and in diabetes-induced depression.  相似文献   
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Behavioral disturbances have been reported with subthalamic (STN) deep brain stimulation (DBS) treatment in Parkinson's disease (PD). We report correlative functional imaging (fMRI) of mood and motor responses induced by successive right and left DBS. A 36-year-old woman with medically refractory PD and a history of clinically remitted depression underwent uncomplicated implantation of bilateral STN DBS. High-frequency stimulation of the left electrode improved motor symptoms. Unexpectedly, right DBS alone elicited several reproducible episodes of acute depressive dysphoria. Structural and functional magnetic resonance imaging (fMRI) imaging was carried out with sequential individual electrode stimulation. The electrode on the left was within the inferior STN, whereas the right electrode was marginally superior and lateral to the intended STN target within the Fields of Forel/zona incerta. fMRI image analysis (Analysis of Functional NeuroImages, AFNI) contrasting OFF versus ON stimulation identified significant lateralized blood oxygen level-dependent (BOLD) signal changes with DBS (P < 0.001). Left DBS primarily showed changes in motor regions: increases in premotor and motor cortex, ventrolateral thalamus, putamen, and cerebellum as well as decreases in sensorimotor/supplementary motor cortex. Right DBS showed similar but less extensive change in motor regions. More prominent were the unique increases in superior prefrontal cortex, anterior cingulate (Brodmann's area [BA] 24), anterior thalamus, caudate, and brainstem, and marked widespread decreases in medial prefrontal cortex (BA 9/10). The mood disturbance resolved spontaneously in 4 weeks despite identical stimulation parameters. Transient depressive mood induced by subcortical DBS stimulation was correlated with changes in mesolimbic cortical structures. This case provides new evidence supporting cortical segregation of motor and nonmotor cortico-basal ganglionic systems that may converge in close proximity at the level of the STN and the adjacent white matter tracts (Fields of Forel/zona incerta).  相似文献   
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BACKGROUND: Chlorofluorocarbon (CFC)-free metered-dose inhalers (MDIs) were introduced into Australia in 1999. Device care instructions were modified (e.g., CFC-free salbutamol inhalers to be washed weekly), but this information was not communicated directly to health care professionals. OBJECTIVE: This pilot study aimed to assess the level of awareness of device care protocols for CFC-free MDIs by patients and their pharmacists. SETTING AND DESIGN: Purchasers of CFC-free MDIs were recruited from four community pharmacies. They were interviewed regarding information sources, knowledge of propellant change, and awareness of and adherence to device care protocols. The dispensing pharmacists were interviewed for knowledge of CFC-free device care. The primary outcome variable was awareness of the relevant device care protocol. RESULTS: Thirty-nine patients were interviewed. Most patients (77%) were aware of the change to CFC-free propellant. Only nine patients (23%) were aware of the need to wash the device holder, and four patients (10% of total) complied with the specified protocol. One of the ten dispensing pharmacists could describe correct device care protocols for the CFC-free MDIs. CONCLUSIONS: Although most patients are aware that MDIs are now CFC-free, there is a low level of awareness of the device care required for these inhalers, and a very low rate of compliance with recommended practice. Although the clinical impact of failing to wash the device holder is unclear, this added instruction may have substantial implications for patient satisfaction and medication delivery. Pharmaceutical manufacturers need to highlight to health care professionals any clinically important changes in device care instructions, so that appropriate information may be passed on to patients.  相似文献   
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To determine whether the improved survival of very low birthweight (VLBW) infants (< 1500 g) born in Australia can be attributed to currently high rates of Caesarean section, we examined the associations between neonatal mortality and Caesarean section in singleton liveborn VLBW infants (500–1499 g) born during 1986–93 in Victoria, Australia, using data from the Victorian Perinatal Collection Unit. The infants included in this study had completed > 23 weeks of gestation, had no life-threatening malformations and had not been delivered by a repeat Caesarean without a trial of labour (n = 2763). For infants weighing 500–749 g, 750–999 g, 1000–1249 g and 1250–1499 g, the neonatal mortality rates were 56.1%, 25.7%, 13.0% and 4.3% respectively, and the Caesarean section rates were 33.1%, 42.3%, 54.8% and 55.8%. Nearly half of these births (n = 1269) were associated with one or more obstetric indications for Caesarean section (non-breech malpresentaion, fetal distress, prolapsed cord, placenta praevia, pre-eclampsia and hypertension). Overall, the odds ratio (OR) for neonatal death associated with Caesarean section was 0.92 [95% confidence interval 0.60–1.41], after adjustment for gestational age, birthweight, year of birth, type of hospital, presence or absence of labour, presentation and obstetric indications for Caesarean section. However, when the vertex-presenting (n = 1702) and breech-presenting (n = 746) infants were considered separately, the adjusted ORs for neonatal death were 1.98 [0.96–4.10] and 0.52 [0.29–0.96] respectively. For those infants without obstetric indications for Caesarean section, the adjusted ORs for neonatal death in vertex-presenting (n = 950) and breech-presenting (n = 446) infants were 3.80 [1.11–13.0] and 0.47 [0.23–0.6]. These recent population - based data support the view that Caesarean section does not enhance the neonatal survival of VLBW babies when obstetric complications are absent.  相似文献   
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