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81.
An intriguing quality of our brain is that when actions are imagined, corresponding brain regions are recruited as when the actions are actually performed. It has been hypothesized that the similarity between real and simulated actions depends on the nature of motor representations. Here we tested this hypothesis by examining S.D., who never used her legs but is an elite wheel chair athlete. Controls recruited motor brain regions during imagery of stair walking and frontal regions during imagery of wheel chair slalom. S.D. showed the opposite pattern. Thus, brain simulation of actions may be grounded in specific physical experiences.  相似文献   
82.
Objective - The underlying mechanisms of the differences in sex distribution of patients with atrioventricular (AV) nodal re-entrant tachycardia and Wolff-Parkinson-White syndrome are poorly understood. The objective of this study was to determine potential gender differences in the electrophysiological properties of the normal AV conduction system that may be attributable to differences in sex distribution. Design - The AV conduction properties were studied in 96 patients (52 men and 44 women) who underwent electrophysiological testing, 32 patients with atrial tachycardia, 39 with idiopathic ventricular tachycardia and 25 with unexplained palpitations or syncope. Results - The AH (83 &#45 15 ms) and His-ventricular intervals in men (42 &#45 6 ms) were significantly longer than in women (78 &#45 14, 38 &#45 6 ms, p < 0.05, respectively), as was the PR interval (160 &#45 17 vs 152 &#45 13 ms, p = 0.02). The effective refractory period of AV node in men (349 &#45 75 ms) was longer than in women (297 &#45 45 ms, p = 0.03). However, no significant difference was observed between men and women with respect to the incidence of AV nodal dual pathway and the maximum AH interval achieved during premature stimulation or incremental pacing. The AV block cycle length was significantly longer in men (371 &#45 76 ms) than in women (330 &#45 52 ms, p = 0.02). A longer ventriculoatrial block cycle length was also found in men than in women although not at a significant level (436 &#45 107 vs 384 &#45 90 ms, p = 0.08). In addition, men (23%) were twice as likely to have ventriculoatrial dissociation during ventricular pacing as women were (11%, p = 0.2). Conclusion - The data show that gender-related differences in AV conduction properties may be responsible for the differences in sex distribution observed in patients with AV nodal re-entrant tachycardia and those with ventricular pre-excitation.  相似文献   
83.
In allowing compression along the femoral shaft (uniaxial dynamization) and optional compression along the femoral neck (biaxial dynamization), the Medoff sliding plate (MSP) represents a new principle in the fixation of trochanteric hip fractures. The Twin hook with 2 apical hooks was designed as an alternative to the lag screw. In 3 prospective consecutive case series and 1 prospective randomized study together comprising 342 trochanteric fractures, these alternative techniques were investigated. 3 postoperative fixation failures occurred in the unstable intertrochanteric fractures treated with biaxial dynamization with the MSP (n=194), and 5 in those treated with the sliding hip screw (n=62) (p=0.04). A mean femoral shortening of 15 mm with the MSP and 11 mm with the sliding hip screw was found (p=0.03). More medialization of the femoral shaft occurred with the sliding hip screw (26%) than with the MSP (12%) in patients with marked femoral shortening (p=0.03). 3 postoperative fixation failures occurred in subtrochanteric fractures treated with uniaxial dynamization (n=29) and 2 in those treated with biaxial dynamization (n=19). Medialization of the femoral shaft occurred in 9 of the 19 biaxially dynamized fractures. The Twin hook was used in 50 patients and appeared to provide similar fixation stability as the lag screw. Biomechanical tests confirmed improved stress transmission over the fracture area with the MSP compared to the sliding hip screw in intertrochanteric fractures, and similar fixation stability with the MSP and the Intramedullary Hip Screw in subtrochanteric fractures. In axial and torsional loading, the Twin hook demonstrated gradually increasing resistance to migration. With the lag screw, the peak load was higher, but after migration with failure of the support by the threads, the loads were similar. Biaxial dynamization with the MSP appears to control fracture impaction effectively and minimizes the rate of postoperative fixation failure in intertrochanteric fractures. In subtrochanteric fractures, uniaxial dynamization prevents medialization of the femoral shaft and is therefore preferred to biaxial dynamization. The Twin hook appears to provide adequate fixation stability, and with potential for simplified intraoperative handling and reduced dissection, the Twin hook may pose advantages compared to the lag screw.  相似文献   
84.
The aim of this study was to compare the safety, morphological outcome, and degree of parental satisfaction of the new spring-mediated cranioplasty with those of the modified pi-plasty in the management of sagittal synostosis. Ten patients with non-syndromic sagittal synostosis treated with the spring-mediated cranioplasty were followed prospectively. A control group of 10 sex-matched patients operated on with the modified pi-plasty procedure was chosen. Cephalometric radiographs were obtained preoperatively and postoperatively at 1 year of age. Cephalic index, axial width ratio, length ratio, width ratio and height ratio were used as objective measures of outcome. Parents were sent a questionnaire to obtain a subjective aesthetic assessment of outcome. Significantly less blood replacement was required (p?=?0.003), and shorter duration of postoperative anaesthesia (p?=?0.030) and postoperative hospital stay (p?=?0.013) were found in the spring-mediated cranioplasty group. There were no complications or deaths in either group. Also significant was the inter-group difference in the postoperative change in the height ratio (p?=?0.030), the most change being seen in the spring group. The change in the subjective parental aesthetic evaluation of skull shape was significant in both groups. In conclusion, the spring-mediated procedure was morphologically more effective than the modified pi-plasty procedure in the management of sagittal synostosis with the additional benefits of less blood transfusion needed and shorter duration of hospital stay.  相似文献   
85.
Psychosocial development in children with chronic disease is a key issue in paediatrics. This study investigated whether psychosocial adjustment could be reliably assessed with the 42-item Adolescent Adjustment Profile (AAP) instrument. The study mainly focused on adjustment-to-obesity measurement, although it compared three patient groups with chronic conditions. All phenylketonuria (PKU) patients in Sweden between ages 9 and 18 and their parents and teachers were invited to participate. Patients with neurobehavioural syndromes and obesity were age- and gender-matched with PKU patients. Healthy children constituted a reference group. Psychosocial adjustment was measured using the AAP, which is a multi-informant questionnaire that contains four domains. Information concerning parents’ socio-economic and civil status was requested separately. Respondents to the three questionnaires judged the PKU patients to be normal in all four domains. Patients with neurobehavioural syndromes demonstrated less competence and the most problems compared with the other three groups. According to the self-rating, the parent rating and the teacher rating questionnaires, obese patients had internalizing problems. The parent rating and the teacher rating questionnaire scored obese patients as having a lower work capacity than the reference group. Compared with the reference group, not only families with obese children but also families with children with neurobehavioural syndromes had significantly higher divorce rates. Obese patients were also investigated with the Strength and Difficulties Questionnaire (SDQ), another instrument that enables comparison between two measures of adjustment. The AAP had good psychometric properties; it was judged a useful instrument in research on adolescents with chronic diseases.  相似文献   
86.
For adolescent people with ID, falls are more common compared to peers without ID. However, postural balance among this group is not thoroughly investigated. The aim of this study was to compare balance and muscle performance among adolescents aged between 16 and 20 years with a mild to moderate intellectual disability (ID) to age-matched adolescents without ID. A secondary purpose was to investigate the influence of vision, strength, height and Body Mass Index (BMI) on balance. A group of 100 adolescents with ID and a control group of 155 adolescents without ID were investigated with five balance tests and three strength tests: timed up and go test, one leg stance, dynamic one leg stance, modified functional reach test, force platform test, counter movement jump, sit-ups, and Biering-Sørensen trunk extensor endurance test. The results showed that adolescents with an ID in general had significantly lower scores in the balance and muscle performance tests. The group with ID did not have a more visually dominated postural control compared to the group without ID. Height, BMI or muscle performance had no strong correlations with balance performance. It appears as if measures to improve balance and strength are required already at a young age for people with an ID.  相似文献   
87.
88.
89.
T Olofsson  H Odeberg  I Olsson 《Blood》1976,48(4):581-593
The initial rate of phagocytosis, oxygen consumption rate during phagocytosis, bactericidal capacity against Escherichia coli, and the granule protein composition of isolated mature-appearing granulocytes were studied in 23 patients with chronic granulocytic leukemia (CGL) with the simultaneous use of normal controls. The initial rate of phagocytosis was decreased (p less than 0.05) in the CGL patient group, as were oxygen consumption rate (p less than 0.001) and bactericidal capacity (p less than 0.001). Kinetic analysis of the ingestion rate showed CGL granulocytes to have the same capacity to bind the particles as normal granulocytes. Both specific and primary granule protein deficiencies were shown for CGL granulocytes, and these deficiencies were more pronounced at or near blast cell transformation. Analysis of all different granulocyte function parameters showed an inverse correlation to white blood cell counts (p less than 0.01) and to the percentage of immature granulocytes in peripheral blood (p less than 0.001). The leukocytosis doubling time was progressively shortened during the chronic course of the disease. A correlation was found between granulocyte function parameters and leukocytosis doubling time (p less than 0.001), indicating that granulocyte function was progressively deteriorating during chronic phase CGL, and may be an expression of increasing disturbance of the differentiation process.  相似文献   
90.
An increase in the use of cocaine and crack in several parts of Europe has raised the question whether this trend is similar to that of the USA in the 1980s. However, research in the field of cocaine use in Europe has been only sporadic. Therefore, a European multi-centre and multi-modal project was designed to study specific aspects of cocaine and crack use in Europe, in order to develop guidelines for public health strategies. Data on prevalence rates were analysed for the general population and for specific subgroups. Despite large differences between countries in the prevalence of cocaine use in the general population, most countries show an increase in the last few years. The highest rate with a lifetime prevalence of 5.2% was found for the United Kingdom, although with a plateau effect around the year 2000. With regard to specific subgroups, three groups seem to show a higher prevalence than the general population: (1) youth, especially in the party scene; (2) socially marginalized groups, such as homeless and prostitutes or those found in open drug scenes; (3) opiate-dependent patients in maintenance treatment who additionally use cocaine. Specific strategies need to be developed to address problematic cocaine use in these subgroups.  相似文献   
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