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51.
52.
The aim of the study was to assess the effect of a comprehensive prophylactic regimen in reducing the incidence of white spot lesions (WSL) and caries during orthodontic treatment. Eighty consecutive patients, scheduled for fixed appliance treatment in both jaws were compared with a non-orthodontic matched-control group. The oral hygiene regimen consisted of brushing two to three times daily, flossing, fluoride rinse, and plaque disclosing tablets. Patients were requested to avoid carbonated soft drinks/acidic juices and candies. The WSL index of Gorelick et al. (Gorelick L, Geiger A M, Gwinnett A J 1982 Incidence of white spot formation after bonding and banding. American Journal of Orthodontics 81: 93-98) was used. Caries were scored according to Amarante et al. (Amarante E, Raadal M, Espelid I 1998 Impact of diagnostic criteria on the prevalence of dental caries in Norwegian children aged 5, 12 and 18 years. Community Dental Oral Epidemiology 26: 87-94). We collected data from all finished cases. It comprised 40 subjects in the orthodontic group (mean age: 13.6 years, range: 12-16 years) and 40 matched controls. The average treatment time was 18 months (range: 9-25 months). The mean increase in WSL index in the orthodontic group was 1.9 and 0.4 in the control group (P = 0.001). The mean increase in dentine caries was 0.5 lesions and 0.7 lesions in the in the orthodontic group and control group, respectively (P = 0.62). Twenty-three per cent of treated patients showed good compliance, 68 per cent moderate compliance, and 9 per cent poor compliance. The mean increase in WSL was 1.0, 1.4, and 3.3 in the good, moderate, and poor compliance group, respectively (P = 0.155). Orthodontically treated patients have significantly higher risk for developing WSL than untreated patients, while there is no difference with respect to development of new dentinal caries lesions. This study showed that a possible relationship between compliance and WSL development existed.  相似文献   
53.
The optimal combination of region-of-interest (ROI) size and strain length (SL) allowing two-segment strain and strain rate analyses in term neonates was investigated. The impact of different ROI sizes and SLs on the strain and strain rate beat-to-beat variation (BBV) was assessed in 80 good-quality tissue velocity images. Both BBVs decreased with increased ROI length and with increased SL (p < 0.05). There were no significant differences in the BBVs for ROI width 2, 3 and 4 mm (p > 0.05). Among the combinations eligible for two segment analysis, the lowest BBVs were found using SL 10 mm, ROI length 1 mm and ROI width 3 mm. Using this combination, the mean difference between the single-cycle value and two-cycle compound value for peak systolic strain rate was 6.2%, peak systolic strain was 2.9% and end systolic strain was 3.2% of the two-cycle compound mean values. Hence, strain and strain rate measurement in tissue velocity images in neonates is feasible and reliable.  相似文献   
54.
In humans, intermittent and continuous theta‐burst stimulation (iTBS and cTBS) elicit long‐term changes in motor‐evoked potentials (MEPs) reflecting long‐term potentiation (LTP)‐ and depression (LTD)‐like plasticity in the primary motor cortex (M1). In this study, we used TBS to investigate M1 plasticity in patients with MSA. We also assessed whether responses to TBS reflect M1 excitability as tested by short‐interval intracortical inhibition (SICI), intracortical facilitation (ICF), short‐interval intracortical facilitation (SICF), and the input/output curves. We studied 20 patients with MSA and 20 healthy subjects (HS). Patients were clinically evaluated with the Unified Multiple System Atrophy Rating Scale. The left M1 was conditioned with TBS. Twenty MEPs were recorded from the right first dorsal interosseous muscle before TBS and 5, 15, and 30 minutes thereafter. In a subgroup of 10 patients, we also tested MEPs elicited by SICI, ICF, SICF, and input/output curves, before TBS. Between‐group analysis of variance showed that at all time points after iTBS MEPs increased, whereas after cTBS they decreased only in HS. In both subgroups tested, patients with predominant parkinsonian and cerebellar features, iTBS and cTBS left MEPs unchanged. MSA patients had reduced SICI, but normal ICF, SICF, and input/output curves. No correlation was found between patients' clinical features and responses to TBS and M1 excitability variables. These findings suggest impaired M1 plasticity in MSA. © 2013 International Parkinson and Movement Disorder Society  相似文献   
55.
Summary We have investigated the effect of long-term strict glycaemic control on peripheral and autonomic nerve function in 45 IDDM patients (age 18–42 years, diabetes duration 7–23 years) without clinical signs of neuropathy or other neurological disease. They were randomly assigned to treatment either with continuous insulin infusion, multiple injections (4–6 times daily), or conventional treatment (twice daily) for 4 years and followed prospectively for 8 years. Motor and sensory nerve conduction velocities were measured at the start and after 8 years. Autonomic nerve function tests were performed only once, after 8 years. A significant reduction of nerve conduction velocity was observed during 8 years in patients with mean HbA1 more than 10% (n=12, group mean 10.9%, range 10.1–13.2%) compared to patients with HbA1 less than 10% (n=33, group mean 9.0%, range 7.5–9.9%). Change of motor nerve conduction velocity in the peroneal nerve was: –4.8±4.9 (SD) vs –2.2±5.3 m/s (p<0.01). Change of motor nerve conduction velocity in the posterior tibial nerve was: –6.8±5.7 vs –3.9±5.1 m/s (p<0.05). No significant changes were observed in the ulnar nerve. Change of sensoric nerve conduction velocity in the sural nerve was: –8.9±8.0 vs –4.6±5.3 m/s (p<0.05). Multiple regression analysis showed that a change in HbA1 of 1% resulted in a 1.3 m/s change in nerve conduction velocity during 8 years. A significantly lowered heart-rate variation during deep breathing (p<0.05) and heart-rate response to standing (p<0.01) was found in patients with HbA1 more than 10% compared to patients with HbA1 less than 10%. This study confirms that the long-term lowering of blood glucose retards the deterioration in nerve conduction velocity observed in the diabetic nerve.Abbreviations IDDM Insulin-dependent diabetes mellitus  相似文献   
56.
Our aim was to study autonomic function in patients with Irritable bowel syndrome (IBS) without constipation and psychiatric comorbidity. Respiratory sinus arrhythmia (RSA) (representing cardiac vagal activity), skin conductance (representing sympathetic activity) and heart rate were measured at baseline and as a response to emotional stress and rectal discomfort in 33 women with IBS and 21 healthy women. Baseline heart rate was higher in the patients than in the healthy volunteers. Both groups had decreased RSA and increased heart rate and skin conductance level when exposed to emotional stress, but the autonomic responses did not differ significantly between the groups. At discomfort threshold the patients had increased heart rate response and skin conductance amplitude when compared to the healthy volunteers. Correlations between autonomic responses and the depression subscale of the Hospital Anxiety and Depression (HAD) score differed markedly between the diarrhea-predominant IBS patients and the IBS patients with alternating stool habits.  相似文献   
57.
Atherosclerosis is a chronic inflammatory disease of arteries. It is triggered by proinflammatory mediators which induce adhesion molecules (eg, vascular cell adhesion molecule [VCAM]-1) in endothelial cells (ECs) by activating p38 and c-Jun N-terminal kinase (JNK) mitogen-activated protein (MAP) kinases by phosphorylation. Blood flow influences atherosclerosis by exerting shear stress (mechanical drag) on the inner surface of arteries, a force that alters endothelial physiology. Regions of the arterial tree exposed to high shear are protected from endothelial activation, inflammation, and atherosclerosis, whereas regions exposed to low or oscillatory shear are susceptible. We examined whether MAP kinase phosphatase (MKP)-1, a negative regulator of p38 and JNK, mediates the antiinflammatory effects of shear stress. We observed that expression of MKP-1 in cultured ECs was elevated by shear stress, whereas the expression of VCAM-1 was reduced. MKP-1 induction was shown to be necessary for the antiinflammatory effects of shear stress because gene silencing of MKP-1 restored VCAM-1 expression in sheared ECs. Immunostaining revealed that MKP-1 is preferentially expressed by ECs in a high-shear, protected region of the mouse aorta and is necessary for suppression of EC activation at this site, because p38 activation and VCAM-1 expression was enhanced by genetic deletion of MKP-1. We conclude that MKP-1 induction is required for the antiinflammatory effects of shear stress. Thus, our findings reveal a novel molecular mechanism contributing to the spatial distribution of vascular inflammation and atherosclerosis.  相似文献   
58.
59.
This retrospective study from three catchment-area-based acute psychiatric wards showed that of all the pharmacologically and mechanically restrained patients (n=373) 34 (9.1%) had been frequently restrained (6 or more times). These patients accounted for 39.2% of all restraint episodes during the two-year study period. Adjusted binary logistic regression analyses showed that the odds for being frequently restrained were 91% lower among patients above 50 years compared to those aged 18–29 years; a threefold increase (OR=3.1) for those admitted 3 times or more compared to patients with only one stay; and, finally, a threefold increase (OR=3.1) if the length of stay was 16 days or more compared to those admitted for 0–4 days. Among frequently restrained patients, males (n=15) had significantly longer stays than women (n=19), and 8 of the females had a diagnosis of personality disorder, compared to none among males. Our study showed that being frequently restrained was associated with long inpatient stay, many admissions and young age. Teasing out patient characteristics associated with the risk of being frequently restraint may contribute to reduce use of restraint by developing alternative interventions for these patients.  相似文献   
60.
The aim of this case report was to present a case of multiple calcified tuberculous lymph nodes found on a panoramic radiograph coincidently diagnosed in an endodontic clinic. A detailed discussion on the differential diagnosis of similar such calcification found in the same region is also presented. A 14‐year‐old girl was referred to our department with the complaint of painless swelling in the left side of the lower jaw. Clinical and radiographical examinations were performed, leading to the initial diagnosis of chronic periapical abscess. The patient's medical history was re‐evaluated. Advanced imaging and excisional biopsy were performed in order to confirm the final diagnosis. Regarding the presenting signs and symptoms of bilateral carious mandibular molars, a periapical inflammatory process was considered in the provisional diagnosis. A thorough examination and investigations were suggestive of cervical tuberculous lymphadenitis (scrofula), and the patient underwent excision of the same. The clinician should consider the possibility of chronic granulomatous inflammatory lesions in the differential diagnosis of radiopaque lesions.  相似文献   
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