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1.
The objective of this article is to describe various radiographic projections which can be used during endodontic therapy. Changes to the angulation of the X-ray beam in relation to the teeth and film can help diagnosis and treatment by producing images which provide additional information not always visible on radiographs taken with standard angulations. For example, changes in angulation can be useful to determine the number and curvature of roots and canals, to identify superimposed roots and to distinguish between anatomical landmarks and apical pathology. Although use of such techniques increases the diagnostic yield of films, it must be appreciated that such views lead to images that are less distinct because of inherent image distortion. Nevertheless, use of the various techniques during endodontics can provide substantial benefit for clinicians in their daily practice.  相似文献   
2.
AStudyonExtension-FlexionDynamicLumbarSpineRadiographsinPatientswithLumbarIntervertebralDiscHerniationAStudyonExtension-Flexi...  相似文献   
3.
Angioedema of the oropharynx and hypopharynx due to oral angiotensin-converting enzyme (ACE) inhibitors is a potentially life-threatening event and has not been well described in the radiology literature. A retrospective review of the clinical and radiologic findings in three patients with angioedema due to ACE inhibitor use was performed.Our subgroup of patients treated with ACE inhibitors presented with varying degrees of dysphagia, dyspnea, and facial swelling. Plain radiographic findings included enlargement of the epiglottis, aryepiglottic folds, and prevertebral and submental soft tissue. Computed tomography confirmed extensive retropharyngeal and subcutaneous edema. Clinical symptoms resolved in each case in 24–48 hours with cessation of the ACE inhibitor and concomitant steriod therapy.Our cases demonstrate the typical clinical and radiographic presentation of neck angioedema in the setting of ACE inhibitor use. As ACE inhibitors are increasingly being used as first-line agents in the treatment of hypertension, we caution that neck angioedema may be encountered with increased frequency in adults. Early recognition and immediate intervention result in rapid resolution of this potentially life-threatening event.  相似文献   
4.
Vanishing fluid collections in interlobar fissures, associated with congestive cardiac failure, are uncommon but well-recognized. Previous studies have highlighted the occurrence of solitary vanishing ‘tumours’, but in the study reported here 7 out of 12 consecutive patients presented with more than one interlobar fluid collection simulating pulmonary tumours. In most cases a lateral radiograph confirmed the correct diagnosis and in all cases follow-up radiographs demonstrated resolution of all pleural fluid collections. In one case ultrasound was helpful. Making the correct diagnosis is very important inorder to prevent inappropriate investigations and treatment such as biopsy or surgery. It is suggested that unusual pleural fluid collections may be more common in communities where pleural disease following stab wounds or tuberculosis are more prevalent.  相似文献   
5.
Objects We evaluated whether the presence of lacunar skull deformity (LSD) with myelomeningocele is a predictive factor for subsequent hydrocephalus development. Materials and methods We reviewed the clinical and radiological records of 18 infants with myelomeningocele, divided the patients into groups with (group A, n=9) and without (group B, n=9) ventriculomegaly at birth and assessed whether the presence of LSD was predictive of the necessity for ventriculoperitoneal shunt (VPS) placement. Results LSD was present in five group A patients. All nine group A patients underwent VPS placement. Among the group B patients, five had LSD; they underwent VPS placement. A significantly higher proportion of those with ventricle enlargement or LSD at birth required VPS placement (p=0.0001). Conclusion Adding to the ventriculomegaly at birth, the presence of LSD alerts to the necessity to monitor these infants closely to determine the necessity for VPS placement.  相似文献   
6.
目的 探讨平片在腹股沟疝无张力疝修补术中的应用。方法 对我科2003年10-2006年10月收冶的125例腹股沟疝患者采用平片无张力腹股沟疝修补术的疗效进行回顾性分析。结果 所有患者均治愈出院,术后无切口感染,除2例残留疝囊处血肿外无其他不良并发症,随访2个月~36月无复发。结论 平片应用于腹股沟疝的修补,具有易掌握,疗效好,费用低,值得广泛开展应用。  相似文献   
7.
Zusammenfassung Anhand einer prospektiven, auslesefreien Serie von 22 Patienten mit perforierten Ulcera im Gastroduodenalbereich verweisen wir auf die begrenzte diagnostische Aussagekraft einfacher anamnestischer, klinischer und radiologischer Daten. Lediglich bei acht Patienten (36%) ergaben sich wesentliche Indizien aus Krankengeschichte und Aufnahmebefund. Bei 16 Patienten (73%) verriet die Thoraxübersichtsaufnahme durch Nachweis einer subphrenischen Luftsichel eine Perforation im Magen-Darm-Trakt. Die Ultraschalluntersuchung wird als bedeutungsvolle Ergänzungsmethode vor allem in der diagnostischen Abklärung radiologisch negativer Ulcusperforationen vorgestellt und diskutiert. Dabei werden die sonographisch faßbare flüssigkeitsbedingte Magendistension sowie das Magenwandödem als unspezifische Kriterien gewertet. Der Objektivierung einer pathologischen Magenkokarde kommt bei gleichzeitigem Nachweis freier Luft und/oder extraluminärer Ingesta sowie freier echoloser Transsudatflüssigkeit pathognomonische Beweiskraft zu. Selbige Ultraschallkriterien erlaubten im einschlägigen Krankengut bei 16 Patienten (73%) eine definitive Diagnose und erfaßte 4 Patienten mit negativem Röntgen. Die kombinierte Analyse radiologischer und sonographischer Befunde führte somit bei 20 Patienten (91 %) unverzüglich zur korrekten Diagnose.
Perforated peptic ulcer: Diagnosis and assessment by sonography
Summary In a prospective unselected series of 22 patients with perforated gastroduodenal ulcers the diagnostic efficacy of clinical and radiologic data was modest. In eight patients only (36%), clinical data yielded sufficient evidence; in 16 patients (73%), plain X-ray demonstrated subphrenic gas. Sonography was proven to be a major advance, especially rewarding in the diagnosis of perforations with negative plain X-ray. Gastric distention and stomach wall edema are unspecifc sonographic criteria, whereas objectivation of a pathologic stomach cockade in the presence of free gas, extraluminary ingesta or echofree fluid in the peritoneal cavity are pathognomonic data. These criteria yielded a definite diagnosis in 16 patients (73%) including four patients with negative X-ray. The combined analysis of radiologic and sonographic findings yielded an immediate correct diagnosis in 20 patients (91%).
  相似文献   
8.
BackgroundAccurate preoperative planning is a key component of successful total hip arthroplasty (THA). The purpose of the present study was to compare the accuracy and reliability of three-dimensional (hipEOS) and common digital two-dimensional (TraumaCad) templating with special focus on stem morphology.Methods51 patients undergoing THA were randomized to two groups. Preoperative planning was performed on 23 patients with hipEOS (3D) and on 28 patients with TraumaCad (2D) planning software. Planning results were compared with the implanted component size. Inter- and intraobserver reliability as well as planning accuracy of both planning methods with special focus on straight and short stem design were recorded.ResultsIntraobserver reliability of both planning methods was good for component planning (ICC2,1: 0.835-0.967). Interobserver ICC2,1 for stem and cup planning were higher for 3D templating (3D ICC2,1: 0.906-0.918 vs. 2D ICC2,1: 0.835-0.843). Total stem and cup size predictions were within 2 sizes for 3D and within 3 sizes for 2D planning. Comparing short stem planning accuracy of both planning methods, absolute difference between implanted and planned component size was significantly lower in 3D planning (P = .029). There was no significant difference in straight stem (P = .935) and cup (P = .954) planning accuracy.ConclusionOur findings suggest that 3D templating with hipEOS software has a good overall reliability and may have a better planning accuracy of short stem prostheses than digital templating with TraumaCad software. Assuming that the number of implanted short stem prostheses will further increase in coming years, a more precise planning with 3D technique can contribute to improve surgery outcome.  相似文献   
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10.
股骨头无血坏死的CT诊断及其与X线平片的关系   总被引:2,自引:0,他引:2  
虽然对股骨头无血坏死的诊断CT不如MRI灵敏,但可与闪烁摄影媲美。我们对20例正常人(共27髋)进行了股骨头CT扫描作为对照,报告了13例(共15髋)股骨头无血坏死的CT所见并与X线平片分期进行了对照.正常股骨头内可见清晰的星芒征,在较低平面于股骨头内侧可见类似双环之现象。股骨头无血坏死时股骨头内星芒征分支融合成丛成簇,可有囊性变及股骨头骨折变形。CT发现骨折的灵敏度比平片高,因此可以提高疾病分期级别,有助于治疗方案的选择。  相似文献   
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