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1.
Research on physical activity (PA) by level of acculturation in Hispanic children is limited and findings have been mixed. We examined PA participation by primary language used with parents in a representative sample of 4th, 8th, and 11th grade Texas public school students. Mixed-effects regression models were conducted using cross-sectional data from the 2004–2005 School Physical Activity and Nutrition Study (n = 22,049). Self-reported PA was compared among three language-ethnic groups: Spanish-Hispanic (SH) (referent); English-Hispanic (EH); and English-Other (EO). EH and/or EO girls were generally between 1.25 and 2.58 [OR] times more likely to participate in PA across grade levels, with the largest differences found for school sports in 8th grade girls. EH and EO 8th grade boys were 1.71 (CI: 1.40, 2.10) and 2.06 (CI: 1.68, 2.51) times, respectively, more likely to participate in school sports. Findings indicate important disparities in Spanish-speaking Hispanic children’s PA participation.  相似文献   
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Heterotopes Pankreasgewebe der Magenwand   总被引:2,自引:0,他引:2  
Heterotopic pancreas is an uncommon cause of gastrointestinal complaints such as epigastric pain, nausea, vomiting, and upper gastrointestinal bleeding. Despite the development of modern diagnostic procedures, it is still difficult to differentiate heterotopic pancreatic tissue from other benign or malignant gastric tumors. Local excision of the gastric wall is regarded as the diagnostic and therapeutic procedure of choice. We present two cases and an overview of the literature.  相似文献   
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A new concept in the surgical treatment of gastroesophageal reflux.   总被引:6,自引:0,他引:6       下载免费PDF全文
Surgical treatment of gastroesophageal reflux has been thought to depend on the construction of a valve mechanism at the gastroesophageal junction (GEJ). Recently, a silicone prosthesis that does not construct a valve has been introduced, and in preliminary studies in the human, shown to be effective in the treatment of reflux. A precise mode of action has not been demonstrated for the prosthesis. This study was undertaken to investigate the mechanics of the prosthesis and determine its effectiveness in an animal model. Six canine gastroesophageal specimens were excised and the lower esophageal sphincter (LES) simulated by a rubber band placed around the GEJ at a tension calibrated to give 25 mmHg "sphincter" pressure. Circumferential silk ligatures of varying length were then placed on the stomach 3.0 cm distal to the GEJ. With no ligature, the LES opening pressure (LESOP) was 8.0 mmHg, varying to 17.0 mmHg with an 8.0 cm ligature. Further, 24 adult mongrel dogs were randomly divided into four equal groups: controls, circular myomectomy of the LES alone, myomectomy combined with fundoplication, and myomectomy combined with implantation of the silicone antireflux prosthesis. Evaluation included manometry, endoscopy, and histology. Although only the normal sphincter and fundoplication responded physiologically, the prosthesis was just as effective in preventing reflux, as evidenced by reducing acid exposure time of myomectomized dogs from 35.4% to 1.8%, and by preventing endoscopic esophagitis. It was concluded that the silicone antireflux prosthesis acts in the same fashion as the ligature in the model, by interrupting distraction of the LES by gastric wall tension. This concept is an effective method for raising LESOP, treating experimental gastroesophageal reflux, and eliminating the sequelae of reflux. Long-term evaluations of the prosthesis are required.  相似文献   
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Background: Several authors have recently reported encouraging results from low-level direct current therapy in easily accessible malignant tumors. However, antitumoral effects in colorectal metastases have not been investigated experimentally. Methods: Using an animal model with induced hepatic metastases, we analyzed the effectiveness and the tumor growth dynamics after direct current application. Three weeks after induction tumor volumes were estimated with magnetic resonance imaging (MRI). Then direct current (80 C/cm3) was applied in the treatment group by means of one anode in the tumor center and four cathodes peripherally. In the control group electrodes were placed without applying current. Tumor growth dynamics was analyzed with MRI after 3 and 5 weeks. After this all animals were killed, and the livers histologically examined. Results: After 5 weeks MRI showed a 1.6-fold tumor enlargement in the treatment group versus a 2.9-fold enlargement in the control group (Student t test, P = 0.0051). The histopathologic analysis of the treated livers yielded a 21% complete response rate and a 78% partial response rate. No necroses were found in the control group. Conclusions: These results confirm the effectiveness of low-level direct current application as a potential modality for the treatment of hepatic metastases.  相似文献   
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Setting: Tanzania is a high-burden country for tuberculosis (TB), and prisoners are a high-risk group that should be screened actively, as recommended by the World Health Organization. Screening algorithms, starting with chest X-rays (CXRs), can detect asymptomatic cases, but depend on experienced readers, who are scarce in the penitentiary setting. Recent studies with patients seeking health care for TB-related symptoms showed good diagnostic performance of the computer software CAD4TB.Objective: To assess the potential of computer-assisted screening using CAD4TB in a predominantly asymptomatic prison population.Design: Cross-sectional study.Results: CAD4TB and seven health care professionals reading CXRs in local tuberculosis wards evaluated a set of 511 CXRs from the Ukonga prison in Dar es Salaam. Performance was compared using a radiological reference. Two readers performed significantly better than CAD4TB, three were comparable, and two performed significantly worse (area under the curve 0.75 in receiver operating characteristics analysis). On a superset of 1321 CXRs, CAD4TB successfully interpreted >99%, with a predictably short time to detection, while 160 (12.2%) reports were delayed by over 24 h with conventional CXR reading.Conclusion: CAD4TB reliably evaluates CXRs from a mostly asymptomatic prison population, with a diagnostic performance inferior to that of expert readers but comparable to local readers.  相似文献   
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Background

It is well documented in the literature that low socioeconomic status (SES) is associated with lower consumption of healthy foods and that these differences in consumption patterns are influenced by neighborhood food environments. Less understood is the role that SES differences in physical and social aspects of the home food environment play in consumption patterns.

Methods

Using data on 4th grade children from the 2009–2011 Texas School Physical Activity and Nutrition (SPAN) study, we used mixed-effects regression models to test the magnitude of differences in the SPAN Health Eating Index (SHEI) by parental education as an indicator of SES, and the extent to which adjusting for measures of the home food environment, and measures of the neighborhood environment accounted for these SES differences.

Results

Small but significant differences in children’s SHEI by SES strata exist (-1.33 between highest and lowest SES categories, p<0.01). However, incorporating home food environment and neighborhood environment measures in this model eliminates these differences (-0.7, p=0.145). Home food environment explains a greater portion of the difference. Both social (mealtime structure) and physical aspects (food availability) of the home food environment are strongly associated with consumption of healthy and unhealthy foods.

Conclusions

Our findings suggest that modifiable parent behaviors at home can improve children’s eating habits and that the neighborhood may impact diet in ways other than through access to healthy food.
  相似文献   
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Background

Clinical reasoning is based on the declarative and procedural knowledge of workflows in clinical medicine. Educational approaches such as problem-based learning or mannequin simulators support learning of procedural knowledge. Immersive patient simulators (IPSs) go one step further as they allow an illusionary immersion into a synthetic world. Students can freely navigate an avatar through a three-dimensional environment, interact with the virtual surroundings, and treat virtual patients. By playful learning with IPS, medical workflows can be repetitively trained and internalized. As there are only a few university-driven IPS with a profound amount of medical knowledge available, we developed a university-based IPS framework. Our simulator is free to use and combines a high degree of immersion with in-depth medical content. By adding disease-specific content modules, the simulator framework can be expanded depending on the curricular demands. However, these new educational tools compete with the traditional teaching

Objective

It was our aim to develop an educational content module that teaches clinical and therapeutic workflows in surgical oncology. Furthermore, we wanted to examine how the use of this module affects student performance.

Methods

The new module was based on the declarative and procedural learning targets of the official German medical examination regulations. The module was added to our custom-made IPS named ALICE (Artificial Learning Interface for Clinical Education). ALICE was evaluated on 62 third-year students.

Results

Students showed a high degree of motivation when using the simulator as most of them had fun using it. ALICE showed positive impact on clinical reasoning as there was a significant improvement in determining the correct therapy after using the simulator. ALICE positively impacted the rise in declarative knowledge as there was improvement in answering multiple-choice questions before and after simulator use.

Conclusions

ALICE has a positive effect on knowledge gain and raises students’ motivation. It is a suitable tool for supporting clinical education in the blended learning context.  相似文献   
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