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21.
The aim of this study was to compare two different types of surgical approaches, intrasinus and extramaxillary, for the placement of zygomatic implants to treat atrophic maxillae. A computational finite element simulation was used to analyze the strength of implant anchorage for both approaches in various occlusal loading locations. Three-dimensional models of the craniofacial structures surrounding a region of interest, soft tissue and framework were developed using computed tomography image datasets. The implants were modelled using computer-aided design software. The bone was assumed to be linear isotropic with a stiffness of 13.4GPa, and the implants were assumed to be made of titanium with a stiffness of 110GPa. Masseter forces of 300N were applied at the zygomatic arch, and occlusal loads of 150N were applied vertically onto the framework surface at different locations. The intrasinus approach demonstrated more satisfactory results and could be a viable treatment option. The extramaxillary approach could also be recommended as a reasonable treatment option, provided some improvements are made to address the cantilever effects seen with that approach.  相似文献   
22.
For patients undergoing radical head and neck surgery, the deformity or physical defect adds to the agony. Rehabilitation of patients with such deformities is a challenge for the maxillofacial prosthodontist to enhance the esthetics and give psychological strength to the patient. This clinical report describes the rehabilitation, using a silicone prosthesis, of a large facial and orbital defect due to mucoepidermoid carcinoma.  相似文献   
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Narcolepsy is a rare disorder characterised by sleep disturbances, cataplexy, sleep paralysis and hypnagogic, hypnopompic hallucinations. Although several treatment modalities, such as tricyclic antidepressants or selective serotonin reuptake inhibitors, have been used to treat different symptoms, there is no definite treatment for narcolepsy. Modafinil or amphetamine-like stimulants, such as dexamphetamine or methylphenidate, are used to treat sleepiness. Our case was a 58-year-old woman who was diagnosed as narcolepsy cataplexy syndrome. Her Epworth Sleepiness Scale (ESS) score was 14 and Beck Depression Inventory (BDI) score was 29 in the first evaluation. Imipramine and modafinil were begun for the treatment, but there was no improvement in her symptoms. Subsequently, bupropion was started at 150 mg/day and then dosage was increased to 300 mg/day. She was asymptomatic at the end of 3 months. To our knowledge, this is the second depressive narcoleptic patient who has responded to 300 mg/day of bupropion.  相似文献   
25.
Abstract Objective. Isolated systolic hypertension (ISH) is generally encountered in elderly patients and there are scarce data regarding the renin-angiotensin-aldosterone system (RAAS) activity in patients with ISH. We aimed to determine the plasma renin activity (PRA), plasma aldosterone levels (PAL) and aldosterone/PRA ratio (PAL/PRA) in patients (age >50 years) with ISH and to compare these values with patients with essential hypertension (EH) as well as subjects with normal blood pressure values (control) who have similar age and cardiovascular risk profile. Methods. Consecutively, 42 untreated ISH patients, 30 patients with EH and 29 normal subjects were included in the study. Parameters were presented as median (interquartile range). Results. There were no significant differences regarding age, gender and other cardiovascular risk factors among groups. As expected, systolic, diastolic blood pressure and pulse pressure values were significantly different among groups. Besides, PRA values were found to be significantly lower in patients with ISH (0.4 [0.2-1.1] ng/ml/h) compared with the EH (0.95 [0.5-2.6] ng/ml/h, p =0.024) and control (1.3 [0.7-2.1] ng/ml/h, p =0.001) groups. Although, PAL were similar among groups, PAL/PRA ratio was significantly higher in ISH group (134.1 [73-224]) compared with those with EH (42.2 [35-84], p <0.001) and the control group (53.3 [30-106], p =0.001). No significant difference was present with respect to PAL/PRA ratio between EH and control groups. Conclusions. Our findings suggested that in patients with ISH, despite lower PRA levels, PAL/PRA ratio is significantly higher compared with the patients with EH and subjects with normal blood pressure. Since higher PAL/PRA levels is an indicator of relative aldosterone excess, medications blocking RAAS activity including aldosterone antagonists may have useful cardiovascular consequences in addition to their antihypertensive effects in ISH.  相似文献   
26.
Endoscopic transsphenoidal surgery is emerging as a minimally invasive and maximally effective procedure for pituitary adenomas. In this report we analyzed the complications in 624 procedures of endonasal transsphenoidal endoscopic surgery in the treatment of 570 patients with pituitary adenomas. The leading author (MB) operated pituitary adenomas via pure endoscopic endonasal transsphenoidal surgery between January 2006 and August 2011 at the Hacettepe University, Department of Neurosurgery in Ankara. Complications were assessed in 624 surgical procedures under five groups; rhinological, CSF leaks, infection, vascular and endocrinologic complications. We observed a total of 76 complications (12.1%). Rhinological complications occurred in 8 patients (1.3%): 4 epistaxis (0.6%) and 4 hyposmia (0.6%). Postoperative CSF leaks occurred in 8 patients (1.3%), and infectious complications occurred in 8 patients: 3 cases of sphenoidal sinusitis (0.4%), 5 cases of meningitis (0.8%). Only 1 case of internal carotid aneurysm rupture during the opening of sellar floor (0.16%) was observed. Endocrinologic complications occurred in 51 (8.1%) patients: Anterior pituitary deficiency in 12 (1.9%), transient diabetes insipidus (DI) in 29 (4.6%), permanent DI in 3 (0.4%) and inappropriate antidiuretic hormone secretion syndrome occurred in 7 (1.1%). There was no mortality directly related to the surgical procedure. The complication rates observed in our study suggests that the endoscopic pituitary surgery is at least as safe as microscopic transphenoidal surgery. These rates were obtained with due experience and well-coordinated teamwork. To further improve these rates, new technological developments will be helpful.  相似文献   
27.
An 18-year-old female came to our clinic with complaints of a tender lump just under her jaw on the left side and another lump in front of her left ear, ecchymosis around the eye and some redness in the eye at the same side. After administering antibiotic therapy for two days we suspected of tularemia and referred the patient to the Infectious Diseases Department. A serum sample was taken and a fine needle aspiration biopsy was performed. The patient was diagnosed with tularemia, the oculoglandular syndrome of Parinaud. Tularemia should also be kept in mind for differential diagnosis in patients with both ocular and glandular symptoms in endemic regions like Turkey and the appropriate therapy should be initiated immediately.  相似文献   
28.

Background

Inguinal hernias are a common cause of groin pain. Most hernias are detectable by clinical examination and many patients proceed to hernia repair on the basis of history and examination findings alone. However, a significant proportion of patients with symptoms suggestive of groin hernia are found to have a normal clinical examination. Several radiological techniques have been developed to solve the dilemma posed by occult inguinal hernias. No systematic review or meta-analysis has addressed this common clinical problem.

Methods

A systematic review and meta-analysis were undertaken of relevant articles in Medline, Embase, and the Cochrane database. Studies were assessed using the QUADAS tool. Statistical analysis was undertaken.

Results

We have shown in this meta-analysis that ultrasound has a sensitivity of 86 % and a specificity of 77 % in occult inguinal hernias. Computed tomography has a sensitivity of 80 % and a specificity of 65 %. Herniography has a sensitivity of 91 % and a specificity of 83 %.

Conclusions

Based on this systematic review, herniography should be considered as the initial investigation for occult inguinal hernia where available. In centers where this is not available, ultrasound of the groin should be used with good clinical judgment. When there is still diagnostic uncertainty, further investigation with magnetic resonance imaging should be considered to exclude alternative pathology.  相似文献   
29.
ATP dependent K channels (K-ATP) take part in the Erythropoietin (EPO) induced cardioprotection but these channel activations have role in cytoprotective role of EPO in the renal ischemia reperfusion (IR) damage is still unknown. For this purpose rats were pretreated with EPO (500 IU/kg) and/or K-ATP channel blocker glibenclamide (40mM/kg) i.p. before bilateral renal IR damage. Renal tissues were used for histological examination and measurement of caspase-3 and TNF-α levels. Renal functions were evaluated by glomerular filtration rate (GFR) fractional excretion of sodium (FENa) and potassium (FEK). Renal TNF-α and caspase-3 levels were decreased in both glibenclamide and EPO-treated IR rats compared to untreated rats. The protection afforded by the pretreatment with EPO alone was greater than that of administering glibenclamide alone. Application of glibenclamide at the same time partly abolished the cytoprotective effect of EPO treatment. K-ATP mediated cytoprotection is not the main mechanism of protective effect of EPO.  相似文献   
30.
BackgroundLisfranc fracture dislocations cause severe tarso-metatarsal malalignment. The research question of this study was to evaluate the severity of the soft tissue injury on the final clinical outcome and compare that with the effect of various determinants on the disability in daily living activities after open reduction and internal fixation of a Lisfranc injury.MethodsThis study consisted of a retrospective analysis of patients with Lisfranc fracture dislocations who were treated by open reduction and internal fixation beween 2004 and 2009. Evaluation focused mainly on the severity of the soft tissue injury, age, fracture classification, time to operation, posttraumatic osteoarthritis, and the results were compared with American Foot and Ankle Society (AOFAS) scores, and Foot and Ankle Disability Index (FADI). Eight patients had Tscherne Grade 1, 13 had Grade 2, and 11 had Grade 3 soft tissue injuries. Myerson classification revealed 11 type A, 8 type B and 13 type C fractures. Six patients’ operations were delayed beyond 8 h.ResultsOf the 38 patients treated in the study period, 32 patients (11 female, 21 male; <30 y-old: 14, >30 y-old: 18) were available for complete follow-up (average, 55.5 months). The comparison of treatment results revealed that those patients with high grade soft tissue injuries had lower AOFAS and FADI scores (43.8 ± 15.9, 53.7 ± 9.4, respectively) when compared to Tscherne Grade 1 injuries (82.8 ± 6.1, 109 ± 13.9, respectively) (p < 0.001). The overall negative impact of the severity of soft tissue injury on functional outcomes had similar significance with regard to post-traumatic osteoarthritis, and fracture type. There was also a statistically significant difference between outcome measures and post-reduction quality (p = 0.002). Patient age (p = 0.9) and delayed surgery (p = 0.5) had no statistically significant effect on the final outcome.ConclusionsSatisfactory results can be achieved with open reduction for Lisfranc injuries. However, despite this treatment, both the severity of the soft tissue injury and non-anatomic reduction are negative prognostic factors in the treatment of Lisfranc fracture dislocations.  相似文献   
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