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11.
Right ventricular involvement is a typical characteristic of Chagas' disease, and it has been described especially in the early stages of the disease. However, the role of right ventricular dysfunction in cardiac failure due to Chagas' cardiomyopathy has not been well established. Seventy-four patients with positive serology tests for Trypanosoma cruzi and Chagas' dilated cardiomyopathy characterized by left ventricular dilatation and systolic dysfunction were studied. Clinical history, physical exam, ECG, chest X-ray and Doppler echocardiogram with color flow mapping were obtained in all. Mean age was 47.5+/-12.9 and 51 were males (69%). Sixty-five patients (88%) were in NYHA functional classes I and II. Mild systolic dysfunction was present in 35 (47%) while in 18 (24%), dysfunction was moderate and in 21 (28%) it was severe. In 43 patients (58%), only the left ventricle was involved by echocardiographic criteria; the remaining 31 patients (42%) showed biventricular involvement. No patient had isolated involvement of the right ventricle. Greater dilation of the right ventricle was associated with larger diastolic (p<0.002) and systolic (p<0.001) diameters of the left ventricle. Systolic pulmonary artery pressure was obtained non-invasively in 54 patients. Pulmonary hypertension was associated with right ventricular dilation (p<0.005) and with systolic dysfunction of the left ventricle (p<0.001). In this group of patients with Chagas' dilated cardiomyopathy, right ventricular dysfunction was present when there was associated and significant involvement of the left ventricle and with higher levels of pulmonary pressure.  相似文献   
12.
Parkinson's disease (PD) is characterised by motor alterations, which are commonly treated with L-DOPA. However, long-term L-DOPA use may cause dyskinesia. Although the pathogenic mechanism of L-DOPA-induced dyskinesia is unclear, the condition has been associated with alterations in dopamine receptors, among which D2 receptors (D2R) have received little attention. This study aims to: (i) develop and standardise an experimental model of L-DOPA-induced dyskinesia in rats with hemiparkinsonism; and (ii) evaluate the correlation between D2R expression and presence of abnormal involuntary movements (AIM). We allocated 21 male Wistar rats into 3 groups: intact controls, lesioned rats (with neurotoxin 6-OHDA), and dyskinetic rats (injected with L-DOPA for 19 days). Sensorimotor impairment was assessed with behavioural tests. Dyskinetic rats gradually developed AIMs during the treatment period; front leg AIMs were more severe and locomotor AIMs less severe (P < .05). All AIMs were significantly evident from day 5 and persisted until the last day of injection. D2R density was greater in the striatum and the medial anterior brain of the lesioned and dyskinetic rats than in those of controls. Our results suggest an association between D2R expression and locomotor AIMs. We conclude that RD2 is involved in L-DOPA-induced dyskinesia.  相似文献   
13.
[Purpose] The aim of the present study was to assess the knowledge of the spine and posture among adolescent female students and to determine if they had access to postural education in or outside school. [Subjects and Methods] This was an epidemiological survey of a representative sample of 495 female students aged 14 to 18 years attending a regular secondary school in São Leopoldo, RS, Brazil. Data were collected through a questionnaire. [Results] The results showed that 16.8% of teens did not know what a spine was, 8.3% had no knowledge of posture, and 61% reported receiving no posture education. Posture awareness was associated only with posture while using a computer, while having postural education class was not associated with any postural behavior. [Conclusion] The results showed that, although most students are familiar with the spine and posture, a sizable group is not, and over half had no postural education. These findings suggest that inclusion of postural education programs in schools should be encouraged in order to promote health and prevent diseases related to the spine.Key words: Posture, Adolescent health, School health  相似文献   
14.
Most mediastinal abscesses result from infections after thoracotomy, esophageal perforation or penetrating chest trauma. This disease is rarely caused by closed blunt chest trauma. All previously reported such cases after closed blunt chest trauma presented with hematoma and sternal osteomyelitis resulting from sternal fracture. Here we report a 15-year-old sumo wrestler who presented with an anterior mediastinal abscess without any mediastinal fracture. The mediastinal abscess resulted from the hematogenous spread of Staphylococcus aureus to a hematoma that might have been caused by a closed blunt chest trauma incurred during sumo wrestling exercises.  相似文献   
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Our goal was to study deglutition of Parkinson??s disease (PD) patients and normal controls (NC) using surface electromyography (sEMG). The study included 15 patients with idiopathic PD and 15 age-matched normal controls. Surface electromyography was collected over the suprahyoid muscle group. Conditions were the following: swallow at once 10 and 20?ml of water and 5 and 10?ml of yogurt of firm consistency, and freely drink 100?ml of water. During swallowing, durations of sEMG were significantly longer in PD patients than in normal controls but no significant differences of amplitudes were found. Eighty percent of the PD patients and 20?% of the NC needed more than one swallow to consume 20?ml of water, while 70?% of the PD patients and none of the NC needed more than one swallow to consume 5?ml of yogurt. PD patients took significantly more time and needed significantly more swallows to drink 100?ml of water than normal controls. We conclude that sEMG might be a simple and useful tool to study and monitor deglutition in PD patients.  相似文献   
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18.

OBJECTIVE

To analyze the career path and professional satisfaction of alumni from the doctorate degree programs in health sector.

METHODS

Exploratory study with 827 alumni of doctoral programs in public health, biological and health sciences at the Fundação Oswaldo Cruz , RJ, Southeastern Brazil, from1984 to 2007. The subjects were grouped in three cross-temporal cohorts according to year. The profiles of the alumni were analyzed, their career paths mapped and information on the perceptions of the education they received and the reasons that led them to choose the institute for their doctoral courses gathered, as well as their evaluations of the courses. The data were collected by means of an online questionnaire.

RESULTS

There are differences between cohorts of alumni related to the periods they followed the courses, their distinct educational backgrounds and labor processes between those from the biological and health sciences areas, and to the specificities of the different areas where the institution offers doctoral courses: public health, biological and health sciences.

CONCLUSIONS

The results allow the academic management of the educational processes to expend its knowledge, thus establishing a baseline for tracking the trajectory of alumni, and may contribute to upgrading the follow up process of Brazilian graduate programs.  相似文献   
19.
Surfactants have long been known to have microbicidal action and have been extensively used as antiseptics and disinfectants for a variety of general hygiene and clinical purposes. Among surfactants, quaternary ammonium compounds (QAC) are known to be the most useful antiseptics and disinfectants. However, our previous toxicological studies showed that QAC are also the most toxic surfactants for mammalian cells. An understanding of the mechanisms that underlie QAC toxicity is a crucial first step in their rational use and in the design and development of more effective and safer molecules. We show that QAC-induced toxicity is mediated primarily through mitochondrial dysfunction in mammalian columnar epithelial cell cultures in vitro. Toxic effects begin at sublethal concentrations and are characterized by mitochondrial fragmentation accompanied by decreased cellular energy charge. At very low concentrations, several QAC act on mitochondrial bioenergetics through a common mechanism of action, primarily by inhibiting mitochondrial respiration initiated at complex I and, to a lesser extent, by slowing down coupled ADP phosphorylation. The result is a reduction of cellular energy charge which, when reduced below 50% of its original value, induces apoptosis. The lethal effects are shown to be primarily a result of this process. At higher doses (closer to the critical micellar concentration), QAC induce the complete breakdown of cellular energy charge and necrotic cell death.  相似文献   
20.
Disease-modifying antirheumatic drugs (DMARDs), a heterogeneous group of drugs, are widely used in rheumatoid arthritis management. The scientific evidence on the management of spondyloarthropathy with DMARDs is limited and the results are inconclusive. In this article, we review the role of DMARDs in the management of axial involvement in spondyloarthropathies, emphasizing its paradigm, ankylosing spondylitis. We review the data published to date on the efficacy and tolerability of salazopyrin, mesalazine, methotrexate, and leflunomide, as well as those of other drugs used on specific occasions such as pamidronate and thalidomide. Data on the effects of this management on peripheral symptoms and organic disease-like uveitis are also included.  相似文献   
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