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991.
OBJECTIVE: To analyze the spatial distribution of leprosy, identify areas of potential case underreporting or high transmission risk, and to assess the ecological association of leprosy distribution with multibacillary cases. METHODS: This study was carried out in 94 neighborhoods of Recife, Brazil. Data was obtained from the Ministry of Health's Disease Reporting System. An ecological approach with the empirical Bayesian method was applied for local rate flattening, using data from a neighborhood matrix. RESULTS: The mean annual occurrence was 17.3% of new cases in individuals under the age of 15 (28.3% corresponded to multibacillary forms), revealing an intense disease transmission. The spatial distribution of leprosy indicated three areas where there was a concentration of high detection rates and low-income neighborhoods. CONCLUSIONS: The Bayesian method allowed to reassess epidemiological indicators based on data from neighboring spatial units. This enabled to identify areas that should be prioritized in municipal control programs, either because of underreporting of cases or the higher number of occurrences related to multibacillary forms in individuals under 15.  相似文献   
992.
BackgroundProcesses underlying cortical hypoactivation in schizophrenia are poorly understood but some evidence suggests that a deficient sensory filtering is associated with the condition. This filtering deficit can be studied by using measures of prepulse inhibition (PPI) of the startle reflex.ObjectiveTo evaluate the contribution of sensory filtering deficits to cortical hypoperfusion during an attention test in schizophrenia.MethodMeasurements of PPI of the startle reflex and perfusion during the performance of a Stroop test (assessed with single photon emission tomography) were obtained in 10 acutely treated schizophrenia patients (6 with recent onset, RO) and 16 control subjects. These measurements were compared between patients and controls and the correlation between PPI and perfusion was evaluated within each group, using Statistical Parametric Mapping.ResultsIn comparison with normal subjects, the patients exhibited lower PPI, although the difference was not statistically significant. Perfusion was significantly lower in the prefrontal and premotor regions of the patients. In the patient group, a statistically significant difference was observed between PPI and perfusion in the parietal, premotor, and cingulate regions. When the associations were analyzed in the RO patients alone, a positive correlation was also found between prefrontal perfusion and PPI, while anterior hippocampal perfusion was inversely related to PPI.ConclusionsThese results support the notion that deficient sensory-motor filtering is associated with decreased cortical task-related activation in schizophrenia.  相似文献   
993.
INTRODUCTION AND OBJECTIVE: The clinical relevance of myocardial bridging (MB) is a matter of debate. The objective of this work was to examine its prevalence, clinical presentation, prognosis, and functional features on scintigraphy in a group of patients with no significant atherosclerotic coronary disease. METHODS: We retrospectively examined 7039 consecutive cardiac angiograms performed between January 1994 and December 2004, selecting cases in which MB was not accompanied by significant coronary disease (defined as luminal stenosis > 50%), valvular heart disease or cardiomyopathy. Patient characteristics such as age, gender, vascular risk factors and clinical presentation were recorded. We then contacted these patients by telephone to determine cardiovascular events since diagnosis (hospitalization, infarction, death) or symptoms of angina, and to invite them for myocardial perfusion scintigraphy (MPS) with stress testing. RESULTS: The prevalence of MB was 0.97% (68 patients). The study population without significant coronary disease, valvular heart disease or cardiomyopathy was composed of 31 subjects, mean age 51.45 +/- 13.77 years, 94% (29 patients) male. Clinical presentations were: non-ST elevation acute coronary syndromes with or without biomarkers of necrosis 34% (14 patients), stable angina 23% (7 patients), atypical chest pain 16% (5 patients), ST-elevation myocardial infarction 13% (4 patients), other 3% (1 patient). Left ventricular function was normal in all patients, and angiography showed MB of the left anterior descending artery, 63% (19 patients) in the mid portion, and 33% (12 patients) in the distal portion. All subjects were treated medically. We were able to contact 24 (77%) of the 31 patients, all of whom underwent MPS; mean time since angiography was 61.25 months, with no cardiovascular events (hospitalization, infarction, death) or symptomatic angina. MPS only identified three patients with findings consistent with anterior wall ischemia. CONCLUSIONS: In this series, 58% of the patients with MB and no significant atherosclerotic coronary disease presented with acute coronary syndromes. In all the subjects contacted, the prognosis had been good during the time since diagnosis. In the majority of them, no signs of ischemia were detected on MPS.  相似文献   
994.
995.
Conventional radiography has shown limitation in acquiring image of the ATM region, thus, computed tomography (CT) scanning has been the best option to the present date for diagnosis, surgical planning and treatment of bone lesions, owing to its specific properties. Objective: The aim of the study was to evaluate images of simulated bone lesions at the head of the mandible by multislice CT. Material and methods: Spherical lesions were made with dental spherical drills (sizes 1, 3, and 6) and were evaluated by using multislice CT (64 rows), by two observers in two different occasions, deploying two protocols: axial, coronal, and sagittal images, and parasagittal images for pole visualization (anterior, lateral, posterior, medial and superior). Acquired images were then compared with those lesions in the dry mandible (gold standard) to evaluate the specificity and sensibility of both protocols. Statistical methods included: Kappa statistics, validity test and chi-square test. Results demonstrated the advantage of associating axial, coronal, and sagittal slices with parasagittal slices for lesion detection at the head of the mandible. Results: There was no statistically significant difference between the types of protocols regarding a particular localization of lesions at the poles. Conclusions: Protocols for the assessment of the head of the mandible were established to improve the visualization of alterations of each of the poles of the mandible''s head. The anterior and posterior poles were better visualized in lateral-medial planes while lateral, medial and superior poles were better visualized in the anterior-posterior plane.  相似文献   
996.
997.
998.
OBJECTIVE: To verify the effects of rapid maxillary expansion performed after secondary alveolar bone graft in one patient. SETTING: Department of Orthodontics of the Hospital for Rehabilitation of Craniofacial Anomalies, University of Sao Paulo. PATIENT(S): The patient had bilateral cleft lip and palate, had already had a bone graft, and showed a relapsing maxillary constriction in need of correction. INTERVENTION: A fixed dental-mucous-bone-supported expander corrected the maxillary constriction. MAIN OUTCOME MEASURE(S): Measurements were obtained from dental casts, including transverse dimensions (intercanine distance [IC], interfirst premolar distance [IP], and interfirst molar distance [IM]) and measurements of the grafted area (interfirst premolar/central incisors [IPI] and interfirst premolar/canine [IPC]) to observe the changes. Clinical and radiographic analyses were done through direct view. RESULTS: The occlusal radiograph of the maxilla after expansion showed opening of the intermaxillary suture in the premaxillary area, which was clinically confirmed by the diastema between the maxillary central incisors. No radiographic alteration was observed in the grafted area. The transverse measurements of the dental casts (IC, IP, and IM) showed a significant increase. The measurements of the teeth adjacent to the grafted area, IPI and IPC, increased. CONCLUSIONS: The orthopedic effect of rapid maxillary expansion after bone graft was verified. Nevertheless, additional studies are necessary to define any side effects in patients submitted to bone graft.  相似文献   
999.
1000.
Osteopetrosis is a rare hereditary bone disorder presenting with variable clinical features and is characterized by an increase in bone density. The main clinical findings of the benign-type of osteopetrosis (autosomal dominant) are fractures and osteomyelitis of the mandible, leading to the detection of the disease. We report a case of autosomal dominant osteopetrosis with secondary mandibular osteomyelitis. Clinical and radiological patterns and treatment evaluation were assessed. The patient was referred for evaluation and treatment of an acute abscess in the left side of the face and osteomyelitis of the mandible. Several imaging studies were performed to assess the lesion and the adjacent bone and soft tissue structures. Treatment consisted of intravenous antibiotic therapy, debridement of the necrotic bone and sequestrum, and extra-oral drainage of the abscess, with submandibular access. Healing was uneventful.  相似文献   
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