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61.
The aim of this study is to evaluate the use of fractional carbon dioxide laser (CO2) with betamethasone and salicylic acid solution in the treatment of patients with refractory vitiligo in hands. Each hand of the patient was randomly assigned to one of two groups: lesion treated with fractional carbon dioxide laser associated with betamethasone and salicylic acid solution administration or lesion treated only with betamethasone and salicylic acid solution. We conclude that combined treatment with fractional carbon dioxide laser and betamethasone associated with salicylic acid solution could effectively and safely be used in the treatment of refractory vitiligo.  相似文献   
62.

Objectives

The purpose of this study was to perform a finite element analysis to determine whether adhesive reconstruction is able to restore the original biomechanical behaviour of weakened roots, in terms of fracture resistance, when compared with post/crown-restored teeth with intact roots.

Methods

A three-dimensional model of a maxillary central incisor was created. The model simulated an endodontically treated tooth restored with a glass-fibre post, a composite-resin core and a metal crown (Model 1). Based on Model 1, a new volume was created in the root cervical third that represented the area where the dentine structure was lost, resulting in a structurally damaged root (Model 2). A 100 N load was applied to the palatal surface at 130° from the long axis of the tooth. After processing (Ansys® 10.0 – Canonsburg, PA, USA), the principal normal stress data were analyzed (S1, tensile; S3, compressive).

Results

The models demonstrated a similar S1 distribution concentrated in the lingual cervical region but different S1 levels (Model 1: 28.7 MPa; Model 2: 35.3 MPa). The S3 distribution indicated differences in behaviour between the models (Model 1: −18 to −27 MPa along the buccal root surface; Model 2: −25 to −32 MPa on the post buccal surface and along the buccal root wall).

Conclusions

Although the stress distribution within the root walls remained below the ultimate stress limit of the root dentine, the adhesive reconstruction of the weakened roots did not recover the load resistance of structurally intact roots.

Clinical significance

The decision of when to prosthetically rehabilitate weakened roots with cervical dentine structural tissue loss is a challenge for clinicians. A ‘monoblock’ adhesive reconstruction has been proposed for root reinforcement. During treatment planning, the possibility of restoring the mechanical resistance of the root must be evaluated if successful long-term results are to be achieved.  相似文献   
63.
Several formulations of alternative alloys have been proposed for the substitution of gold-based alloys used in Dentistry. Recently, a Ni-Cr-Ti-based alloy has been introduced. The purpose of this work was to verify the marginal adaptation obtained with one-piece superstructures for implant-supported prostheses obtained in Ni-Cr-Ti alloy, compared to a semi-noble alloy Pd-Ag. Eight superstructures for each alloy were produced over 4 implants in the anterior region of the mandible. The superstructures were placed in a torquemeter and the fixation screw of implant #1 was tightened with a 20 Ncm load with the others loosened (Sheffield test). The unfitness (in mm) was measured using a three-dimensional optical measurer in each implant, in the buccal and lingual aspects. The obtained data were submitted to statistical analysis by the analysis of variance and Tukey's test at 5% level. Significant differences were found for the factors material (p<0.05), with Ni-Cr-Ti pieces better than Pd-Ag ones, and implants (p<0.01). There were no significant differences for the factor position and interactions among factors (p>0.05). Based on the analysis of the data, it is possible to conclude that the Ni-Cr-Ti alloy makes possible the obtainment of one-piece implant-supported superstructures with a smaller misfit compared to the one obtained in Pd-Ag alloy, traditionally indicated for this situation. Additional tests may verify the superiority of the Ni-Cr-Ti alloy.  相似文献   
64.
BACKGROUND: The hepatocellular carcinoma is a disorder that affects patients suffering from cirrhosis. Liver resection, orthotopic liver transplantation and percutaneous ablation are some forms of therapy currently used to provide a cure for this disease. AIM: To assess the results achieved through liver resection for the treatment of the hepatocellular carcinoma in patients with cirrhosis being under treatment in a general hospital. METHODS: Clinical observation, laboratory test results, endoscopic and histopathologic analysis were taken into consideration in the case of 22 patients who underwent liver resection between 1996 and 2005. To verify the survival rates, identify the prognostic factors and determine the risk of recurrence, special attention was given to the serologic levels of bilirubins and alpha-fetoprotein, and to the level of the hepatocellular dysfunction (classified according to the Child-Pugh-Turcotte and the Model for End-Stage Liver Disease parameters). The size and number of tumours, microvascular invasion and the presence of satellite lesions were also taken into consideration. The level of statistic significance employed was of 95%. RESULTS: In the cases studied, patients had an average age of 62.09 years, being 17 of them male. In 10 cases the liver cirrhosis was associated to the hepatitis C chronic infection; in 4 cases there was a combination of chronic ingestion of ethanol and the hepatitis C virus; in 3 cases there was an association with the hepatitis B virus chronic infection. Two cases were related to the chronic ingestion of ethanol alone and in one case the use of medications was reported. It was not possible to establish the etiology in two of the cases studied. Eighteen patients had a single tumour, 11 of them smaller than 5 cm. The survival rate varied between 10 days and 120 months, being of 33.5 months on average. At the end of the 1st, 3rd and 5th year, the survival rates were 61.90%, 16.67% and 11.11%, respectively. Three patients died within the first 3 months after the liver resection. Thirteen patients died after the first 3 months, 12 of the cases associated to tumour recurrence and tumour progression. There was one death in the immediate post-operative period of a second operation carried out to remove a recurrent tumour. When it comes to the survival rate and the identification of prognostic factors, a relationship between patients survival and microvascular invasion was observed. No statically significant relationship was established between the survival rate and the serologic levels of bilirubins and alpha-fetoprotein or the level of hepatocellular dysfunction, size or number of tumours. However, a more significant incidence of tumour recurrence was observed in patients with microvascular invasion in the histopathologic study. CONCLUSION: In spite of the reduced number of cases studied, the surgical treatment of the hepatocellular carcinoma produced bad results. A careful selection of cases where surgery could be an option may be a decisive factor to improve such results. A careful selection of cases might be a decisive factor in order to improve such results.  相似文献   
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67.
Study of nuclear diameters in non-Hodgkin's lymphomas   总被引:2,自引:5,他引:2       下载免费PDF全文
The mean maximum nuclear diameter (Dmax) in 21 cases of non-Hodgkin's lymphoma (NHL) has been determined, using the Reichert-Jung (Kontron) MOP-AMO3 user-controlled image analyser. Nuclear diameters of high-grade malignancy NHL were found to be considerably greater than those of low-grade malignancy lymphomas, although there was some overlap of their ranges. These findings confirm objectively subjective estimates of nuclear size in NHL. The relative usefulness of the user-controlled (interactive) image analyser for the measurement of nuclei in tissue sections is compared with that of a fully automatic machine.  相似文献   
68.
Immunoglobulin (Ig) was demonstrated in paraffin sections of 12 trephine bone marrow biopsies by means of the unlabelled antibody peroxidase-antiperoxidase (PAP) method. The Ig-containing cells, which were counted with the Reichert-Jung (Kontron) MOP-AMO3 user-controlled image-analyser, were found to constitute approximately 4·2% of all the nucleated cells in the marrow, a figure significantly higher than those reported by previous workers.  相似文献   
69.
A 36 years-old man was admitted in September 1987. For 5 years he suffered from 4 recurrent episodes of throbbing headache, tinnitus, nausea, diplopia and divergent strabismus to which a facial palsy was recently added. In all episodes, the symptoms disappeared spontaneously and completely. A neuro-ophthalmological examination at admission disclosed an exotropia of the right eye, gaze paralysis to the left, paralysis of adduction of the left eye and preserved right eye abduction which triggered a rhythmic horizontal nystagmus. The upward and downward gazes and the convergence were well preserved. Moreover, there was a left peripheral facial palsy, and Babinski sign at the right side. Auditory evoked potentials were slowed at the mesencephalopontine transition. CT scan showed a low-density area with no contrast enhancement at the left pontine tegmentum and a left anterolateral atrophy of the pons. CSF examination showed increase in protein content and increase in the IgG content. Additional investigation included a dopplerometry of the cervical arteries, a panangiography and a bidimensional echocardiography which were normal. Diagnosis of one-and-a-half syndrome was made, possibly secondary to multiple sclerosis, and immunossuppressive therapy was initiated.  相似文献   
70.
The objective of this periodic review was to identify, summarize, and appraise studies relating to the implementation of salt reduction strategies that were retrieved between November 2015 and February 2016. From the established MEDLINE search, 56 studies were identified as relevant to the implementation of salt reduction initiatives. Detailed appraisal was performed on seven studies that evaluated the impact of salt reduction interventions. While study quality varied, all had one or more risks related to bias. There was consistent evidence, from three studies, demonstrating that setting‐based structural interventions to improve the nutritional composition of foods were effective in reducing salt but mixed evidence in relation to the effectiveness of behavioral interventions. The development of an evaluation guidance framework that supports scientific rigor and external validity would aid future design and interpretation of studies evaluating salt reduction interventions, particularly for low‐resource countries.  相似文献   
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