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11.
Techniques of rapid prototyping were introduced in the 1980s in the field of engineering for the fabrication of a solid model based on a computed file. After its introduction in the biomedical field, several applications were raised for the fabrication of models to ease surgical planning and simulation in implantology, neurosurgery, and orthopedics, as well as for the fabrication of maxillofacial prostheses. Hence, the literature has described the evolution of rapid prototyping technique in health care, which allowed easier technique, improved surgical results, and fabrication of maxillofacial prostheses. Accordingly, a literature review on MEDLINE (PubMed) database was conducted using the keywords rapid prototyping, surgical planning, and maxillofacial prostheses and based on articles published from 1981 to 2010. After reading the titles and abstracts of the articles, 50 studies were selected owing to their correlations with the aim of the current study. Several studies show that the prototypes have been used in different dental-medical areas such as maxillofacial and craniofacial surgery; implantology; neurosurgery; orthopedics; scaffolds of ceramic, polymeric, and metallic materials; and fabrication of personalized maxillofacial prostheses. Therefore, prototyping has been an indispensable tool in several studies and helpful for surgical planning and fabrication of prostheses and implants.  相似文献   
12.
The matching of the aesthetic, functional, and psychosocial results of a facial deformity may produce devastating effects in its carriers, especially if the lesion is extensive or the treatment is aggressive. Because of this, the objective of the present article was to evaluate patient's satisfaction rating after surgical facial reconstruction or rehabilitation with oral and maxillofacial prosthesis, by means of reviewing the literature.  相似文献   
13.
This study verifies whether there is any temperature change during photoactivation of two resin composites (Filtek Z250 and Filtek Flow) with three different light curing methods (conventional halogen light curing unit, light emitting diodes curing unit and xenon plasma arc curing unit) and the relationship of temperature change with resin composite hardness. A type-K thermocouple registered the temperature rise peak in an elastomer mold during photoactivation. After photoactivation, the specimens were submitted to Knoop hardness test performed by an indenter (HMV-2000) under a load of 50g for 15 seconds. Both the temperature change data and results of the Knoop hardness test were submitted to ANOVA and Tukey's test at the 5% significance level. No statistical differences in temperature rise were recorded for the different composites following processing by light curing unit (p>0.05). The conventional halogen source produced statistically higher temperatures (p<0.05) than the other units. The plasma arc source promoted statistically lower (p<0.05) Knoop hardness values and temperature changes than the other light curing units.  相似文献   
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Background

Remote ischemic perconditioning (rPER) is the newest technique described to mitigate ischemia and reperfusion (IR) injury. Local postconditioning (POS) is also an effective technique for this purpose. It is uncertain if adding local POS to rPER provides superior liver protection, so we tested this hypothesis.

Materials and methods

Twenty five Wistar rats were assigned into five groups: sham, IR, POS, rPER, and rPER + POS. Animals were subjected to liver ischemia for 60 min. POS consisted of four cycles of 5-min liver perfusion followed by 5-min liver ischemia (40 min total) after the major ischemic period. rPER consisted of four cycles of 5-min hindlimb ischemia followed by 5 min hindlimb perfusion contemporaneously to major liver ischemic period, during its last 40 min. After 2 h, median and left lobes were harvested for malondialdehyde and Trolox equivalent antioxidant capacity (TEAC) measurement, and blood for the measurement of serum transaminases.

Results

All tissue conditioning techniques were able to reduce transaminases serum levels, having no differences among them. All tissue conditioning techniques were able to reduce hepatic tissue MDA level; however, only rPER + POS had higher values than SHAM. All tissue conditioning techniques also enhanced TEAC; however, only POS had lower TEAC than SHAM.

Conclusions

rPER appears as the most promising technique to avoid IR injury. This technique reduced oxidative stress of cell membranes and lowered transaminases serum level. There was no additive protection when POS and rPER were held together.  相似文献   
16.
The brown algal genus Laminaria (Phaeophyceae, Laminariales) is ecologically and economically important. Laminaria ochroleuca is the genus member with the southernmost distribution in the Northern hemisphere, from Southern Great Britain to Morocco. Here we describe the characterization of 15 microsatellite loci that can be used to study genetic diversity at different spatial scales and its dynamics in declining southern populations. These loci identified a number of alleles ranging from 3 to 26 (mean = 9). Expected heterozygosities range from 0.0824 to 0.9401. We also tested cross-amplification of these microsatellite markers in two other species within the genus, L. hyperborea and L. digitata. A total of eight and ten alleles cross-amplified in L. hyperborea and L. digitata, respectively. These 15 variable microsatellite loci are an important molecular tool to conduct population genetics studies in L. ochroleuca and other species within the genus.  相似文献   
17.

Introduction

Despite inguinal hernia repair being one of the most common elective operations performed in general surgical practice, there are many controversies including indications for repair and selection of the surgical technique. In recent years, laparoscopic repair has gained wider acceptance because it is associated with fewer postoperative complications and less chronic pain when compared with conventional approaches with similar recurrence rate. However, patients with lower abdominal surgery are contraindicated for laparoscopic approach. There are few studies that evaluated whether patients who have been subjected to radical prostatectomy might be subjected to laparoscopic hernia repair with the same benefits as those without previous radical prostatectomy.

Methods

Between March 2010 and March 2013, 20 consecutive patients, who had been subjected to prior radical prostatectomy, underwent laparoscopic transabdominal inguinal repair and were followed prospectively. Surgical procedure was performed using a standard technique.

Results

Mean operative time was 67.5 min. There was only one (5 %) intraoperative minor complication, an injury to the inferior epigastric vessels, which was managed by clipping of the vessels. There were no major postoperative complications. After 24 h and on the seventh postoperative day, 85 and 90 % of patients had no pain or only complained of discomfort, respectively. Nine patients (45 %) did not need any analgesics postoperatively. The mean time to return to leisure activities and to work was 3.1 and 5.6 days, respectively. There was no conversion to open surgery. All patients were discharged within 24 h. After a mean follow-up of 14 months, none of the patients presented recurrence.

Conclusion

TAPP after prostatectomy is safe and effective. It seems that patients undergoing laparoscopic repair after radical prostatic resection have the same benefits as those without prostatectomy.  相似文献   
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The purpose of this study was to verify the efficacy of a Perceptual-Motor Competences Training Program upon the performance on UFOV of an experimental active group of elderly drivers. Program tasks were conceived to force subjects to divide their attention for central and peripheral stimuli, using a visual strategy of gazing at an anchor-point and, from there, detect important clues on peripheral visual field. For this purpose, almost all tasks were performed on groups of two, being one responsible for testing the other and switching functions from time to time (for instance, dropping one of two juggling handkerchiefs hold apart, one in each tester hand, with the partner having to detect which was dropped and react as quick as possible, catching it before it felt to the floor). We found a significant improvement in the capacity of dividing attention for central and peripheral stimuli under a visual environment full of distractors (selective attention UFOV test) following the Program, as well as a significant reduction on the category of risk (component based upon the three UFOV subtests results), which evidence very clearly the benefits of this training program on the elderly experimental group and its potential to reduce their risk of being involved in car accidents, on their fault, due to perceptual reasons.  相似文献   
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