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61.

Objective

The goal of this work was to assess the shear bond strength (SBS) and fracture mode of a self-adhering flowable composite when used after thermocycling for lingual retainer bonding.

Materials and methods

A total of 80 human mandibular incisor teeth were categorized into four equal groups: group 1: Vertise? Flow (VF) without acid etching; group 2: VF with acid etching; group 3: VF with a self-etching bonding agent accompanied by an additional acid etching; group 4: Transbond LR control. Either VF or Transbond LR was applied to the lingual surface of the teeth by packing the material into cylindrical plastic matrices to simulate the lingual retainer bonding area. After all teeth were thermocycled (5000 cycles, 5 and 55?°C), fracture modes were examined under ×20 magnification. The SBS data were assessed via analysis of variance (ANOVA) and Tukey’s tests. Fracture modes were analyzed by the χ2 test at a significance level of 0.05.

Results

Statistically significant differences in SBS values between groups (p??<?0.001). In all the self-adhering flowable composite groups, the adhesive type (tooth–composite interface) fracture occurred more frequently than cohesive and mixed-type fractures.

Conclusion

When applied to bond lingual retainers to unetched enamel or with self-etching bonding agent accompanied by an additional acid etching, Vertise? Flow resulted in a significant decrease in bond strength.  相似文献   
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Journal of Neurology - Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease with loss of muscle function. The pathogenesis is still unclear and the heterogeneity of ALS...  相似文献   
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Open in a separate windowOBJECTIVESThis study investigated the efficacy and complications of albendazole use after surgery in patients with pulmonary hydatid cysts.METHODSOne hundred fifty-three consecutive patients who met the study criteria out of 215 patients who received prophylaxis with albendazole after surgery for isolated pulmonary hydatid cysts in our clinic between January 2011 and December 2020 were analysed retrospectively.RESULTSEighty-six out of 153 (56.2%) of cases were male and 67 (43.8%) were female. The average age was 24.6 ± 17.4 (between 3 and 71 years), 76 of them (49.7%) were 18 years old and younger, while 77 (50.3%) were adults. All cases were approached transthoracically and a total of 170 operations were performed on the 153 cases. Fever, weakness and dizziness were reported in only one patient who was given albendazole treatment. A partial increase in liver enzymes was observed in 16 cases (10.5%) after albendazole treatment. Mild leukopoenia and neutropenia were observed in only one of the cases. In 1 case, a second operation was performed 30 months later due to recurrence. Albendazole treatment was not required to be discontinued in any of the cases. Mortality was not observed in any of the cases. Factors such as mean age, cyst size and hospitalization period did not have a statistically significant effect on any changes in liver enzymes tests following albendazole therapy (P > 0.05).CONCLUSIONSAlbendazole treatment can safely be used for postoperative prophylaxis in patients with pulmonary hydatid cysts in a controlled manner without causing serious complications.Subj collection152.  相似文献   
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The possibility for maxillary artery (MA) to petrous internal carotid artery (ICA) bypass was investigated. Five adult cadavers were dissected bilaterally. After zygomatic arch osteotomy, the coronoid process was sectioned at its base. An extensive infratemporal craniotomy was performed at the level of foramina ovale, rotundum and spinosum. The petrous portion of the ICA was exposed by drilling away the floor of the middle fossa, posterior to the foramen ovale and medial to the foramen spinosum. The MA was identified medial to the infratemporal crest and was followed in the pterygopalatine fossa, then transected at the origin of the infraorbital artery. The MA graft was brought posteromedially to reach the petrous ICA. The mean caliber of the MA before the origin of the infraorbital artery was 2.54±0.31 mm, 2.76±0.14 mm at the site of anastomosis, and 3.46±0.32 mm after giving off the middle meningeal artery. The average length of the MA between the middle meningeal artery and the infraorbital artery was 43.4±2.35 mm, and up to the site of anastomosis was 37.64±1.68 mm. We conclude that the length and diameter of the MA are sufficient for a tension-free anastomosis between MA and petrous ICA, and such a procedure could be used in the treatment of patients with tumors of the infratemporal fossa invading the high cervical ICA.

Electronic Supplementary Material The french version of this article is available in the form of electronic supplementary material and can be obtained by using the Springer Link server located at
Étude anatomique des possibilités de by-pass entre la partie pétreuse de l'artère carotide interne et l'artère maxillaire
Résumé La possibilité d'un by-pass entre l'artère maxillaire et la partie pétreuse de l'artère carotide interne a été étudiée. Cinq cadavres adultes ont été disséqués des deux côtés. Après ostéotomie de l'arcade zygomatique, le processus coronoïde était sectionné à sa base. Une large craniotomie infra-temporale était effectuée au niveau du foramen ovale, du foramen rond et du foramen épineux. La partie pétreuse de l'artère carotide interne était exposée par fraisage du plancher de la fosse cérébrale moyenne, en arrière du foramen ovale et en dedans du foramen épineux. L'artère maxillaire était identifiée en dedans de la crête infra-temporale et suivie dans la fosse ptérygo-palatine, puis sectionnée à l'origine de l'artère infra-orbitaire. Le greffon d'artère maxillaire était transposé en dedans et en arrière pour atteindre la partie pétreuse de l'artère carotide interne. Le calibre moyen de l'artère maxillaire était de 2,54±0,31 mm à l'origine de l'artère infra-orbitaire, 2,76±0,14 mm au niveau de l'anastomose, et 3,46±0,32 mm après la naissance à l'artère méningée moyenne. La longueur moyenne de l'artère maxillaire entre l'artère méningée moyenne et l'artère infra-orbitaire était de 43,4±2,35 mm et au-delà du site d'anastomose était de 37,64±1,68 mm. Nous en avons conclu que la longueur et le diamètre de l'artère maxillaire était suffisant pour une anastomose sans tension entre l'artère maxillaire et la partie pétreuse de l'artère carotide interne. Ainsi, une telle technique pourrait être utilisée pour le traitement de patients porteurs d'une tumeur de la fosse infra-temporale envahissant la partie cervicale haute de l'artère carotide interne.
  相似文献   
66.
Case studied Median nerve entrapment is a rare, serious complication of elbow dislocation. We report a Type 4 median nerve entrapment after elbow dislocation in a 10-year-old boy. Radiologically Matev's sign and a new radiological finding—a sclerotic tunnel at the lateral side of the olecranon—were seen.Treatment The patient was treated by excising the damaged segment and reanastomosing the nerve 13 months after the injury.  相似文献   
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Objective:To transplant bone marrow–derived mesenchymal stem cells (MSCs) into the interpremaxillary suture after rapid maxillary expansion with the aim of increasing new bone formation in the suture.Materials and Methods:Nineteen male Wistar rats were divided into two groups (control, n  =  9; experimental, n  =  10). Both groups were subjected to expansion for 5 days, and 50 cN of force was applied to the maxillary incisors with a helical spring. Pkh67+ (green fluorescent dye)–labeled MSCs were applied to the interpremaxillary suture after force application into the interpremaxillary suture of rats. Bone formation in the sutural area was histomorphometrically evaluated, including the amount of new bone formation (µm2), number of osteoblasts, number of osteoclasts, and number of vessels. Mann-Whitney U-test was used for statistical evaluation at the P < .05 level.Results:After 10 days of retention, Pkh67+ can be detected in suture mostly in the injection site under fluorescence microscope. Histomorphometric analysis revealed that a single local injection of MSCs into the midpalatal suture increased the new bone formation in the suture by increasing the number of osteoblasts and new vessel formation, compared with controls injected with phosphate-buffered saline.Conclusions:This preclinical study might provide foundations for the underlying potential clinical use of MSCs after maxillary expansion. Given the fact that MSCs are currently in use in clinical trials, this approach might be a feasible treatment strategy to accelerate new bone tissue formation in midpalatal suture and to shorten the treatment period for patients undergoing maxillary expansion reinforcement  相似文献   
69.
ABSTRACT: Chronic paranasal sinus disease is one of the most common causes of application to physicians in pediatric and adult patients. In the surgical treatment of these diseases, endoscopic sinus surgery is an application that is often done to increase the quality of the patient's life. On account of this, the anatomic variations in skull basement must be well known to avoid possible major complications that may occur during the operation.Recent developments in paranasal sinus surgery also enhanced the need for examining exhaustively the anatomy of this region and existing pathology. Superiority of computed tomography (CT) has an unquestionable importance for the evaluation of anatomic structure and pathology compared with conventional radiographs. A likely anatomic knowledge is needed for a safe surgery. Before the surgery, determining the anatomic variations makes the operation safer and increases the prospects, so we can prevent complications that may occur during the surgery.In this study, CT coronal sections of 300 patients who were admitted to the Department of Ear Nose Throat of Medical Faculty of Cumhuriyet University Research and Training Hospital between the dates December 2008 and January 2011 with complaints of nasal flow and postnasal drip were studied. According to coronal section CT examinations, the patients were divided into 2 groups. Group 1, with 156 cases (64%), showed mucosal changes, and in 144 cases (36%), no mucosal changes were established (group 2). In comparison between the sexes, in groups 1 and 2 females, significant difference was determined for other parameters except the average height of the ethmoid roof. In the comparison between the sexes, in groups 1 and 2 males, significant difference was determined for all parameters. The difference between these 2 rates was statistically significant.Keros types 1 and 2 cases were compared with the control group, and there was no statistically significant difference. Notwithstanding, at the comparison of the Keros type 3 with the control group, there was a statistically significant difference for all the parameters (maximum orbital height, the length of the middle concha, and the nasal wall).It seems to be important for us to know the average length of the peripheral anatomic structures to avoid serious complications that may occur during the operation. Careful preoperative review of paranasal sinus CT scans in patients undergoing sinus surgery seems to be the most important to prevent severe intraoperative complications.  相似文献   
70.
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