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1.
BACKGROUND: This study was undertaken to investigate the effect of long-term blood pressure (BP) reduction, achieved with salt restriction and strict volume control, on frequency and regression of left ventricular hypertrophy (LVH) in long-term peritoneal dialysis (PD) patients. METHODS: 56 patients who had been treated for more than 2 years under our care were enrolled. After echocardiographic (Echo) evaluation, 46 patients were included in the follow-up study. In our unit, we aim to keep patients' BP below 130/85 mmHg and cardiothoracic index below 0.50. To reach these targets, moderate salt restriction is advised, and if necessary, hypertonic PD solutions are used. Echo was performed at the beginning of the study (after a mean period of 36 months on PD) and at the end of the prospective follow-up period (24 months later). RESULTS: At the time of the first Echo, LVH was detected in only 8 (21%) patients. Residual urine volume was significantly decreased compared to data taken when they first started PD (658 +/- 795 vs 236 +/- 307 mL/day). Mean left ventricular mass index (LVMI) was 107 +/- 26.5 g/m2. LVMI was significantly decreased at the end of the follow-up in patients who had LVH at baseline. No LVH developed in patients who had normal LVMI at baseline. CONCLUSION: Our results indicate that control of hypertension is possible when extracellular fluid volume is kept under control using hypertonic PD solutions in case of recruitment in addition to salt restriction in long-term PD patients. Sustained normovolemia is associated with low incidence and regression of LVH.  相似文献   
2.
BACKGROUND: Posterior spinal procedures through tubular exposures have been described. However, tubes restrain visibility and require co-axial instrument manipulation, increasing difficulty and potentially compromising surgical results. An independent-blade retractor system overcomes the obstacles of working through a tube and has been used to perform minimally-disruptive decompression and instrumented tranforaminal lumbar interbody fusion (TLIF). PURPOSE: To evaluate the advantages to patient recovery and surgical efficacy of this technique. METHODS/RESULTS: Retrospective review of technique employing a minimally-disruptive approach to decompression and transforaminal lumber interbody fusion (TLIF). CONCLUSIONS: Minimally-disruptive decompression and instrumented TLIF can be performed in a safe and effective manner using an independent-blade retractor system. Relative to traditional-open techniques, surgical goals can be accomplished, but with the benefits of minimally-disruptive surgery.  相似文献   
3.
When left bundle branch block (LBBB) is present on the electrocardiogram, the diagnosis of left ventricular hypertrophy (LVH) may be difficult. The left ventricular mass in 70 patients with LBBB was estimated by echocardiography, and was compared to the QRS configuration on the electrocardiogram. We found that there was agreement between a monophasic R pattern in lead 1 or V6 (sensitivity 79.3%, 70.7%) and left ventricular hypertrophy. We suggest that a monophasic R pattern in L1 and V6 may provide a useful simple index of left ventricular hypertrophy in the presence of left bundle branch block.  相似文献   
4.
Summary High-resolution computed tomography (HRCT) provides excellent contrast between osseous structures, air and soft tissue in conjunction with high spatial resolution. Therefore, thin-section HRCT with bone window setting is the method of choice for the examination of the middle ear structures. The indications are acute and chronic inflammatory changes, cholesteatoma and tumor, the “postoperative middle ear”, and malformations. In most cases, HRCT enables differentiation between inflammatory changes, cholesteatoma, and tumor. The excellent depiction of subtle osseous details enables the identification of erosions of the ossicles or of the bony walls of the mastoid cells, of osseous defects of the tegmen, of the bony labyrinth, and of the tympanic course of the facial canal. In addition, HRCT enables excellent depiction of reconstructions of the ossicles or prosthesis of the ossicles. Although HRCT is the first method of choice, magnetic resonance imaging (MRI) may provide additional information and lead to a more accurate diagnosis in some cases. This is explained by the excellent soft tissue contrast provided by MRI. In addition, MRI offers the possibility of using various pulse sequences and the administration of IV contrast material. Therefore, MRI may allow the differentiation between inflammatory changes, cholesteatoma, and tumor in those cases in which accurate diagnosis cannot be made by HRCT. The differentiation between a meningocele or meningoencephalocele and other entities such as tumors or cholesteatoma can be established by MRI. Furthermore, MRI can accurately depict cases of labyrinthitis or of neuritis of the facial nerve or of intracranial disease caused by middle ear processes, while this is not always possible by HRCT. In summary, HRCT of the middle ear is the method of choice, but MRI may provide supplementary information in those cases in which accurate diagnosis cannot be established by HRCT.   相似文献   
5.
Tranilast is an antiallergic drug that interferes with proliferation and migration of vascular smooth muscle cell induced by platelet-derived growth factor (PDGF) and transforming growth factor-beta1 (TGF-beta1). We investigated the local effect of tranilast on neointimal hyperplasia using tranilast-coated prosthetic grafts. The inner sides of the thin-walled polytetrafluoroethylene (PTFE) grafts were coated with chitosan and tranilast containing chitosan solution. Wistar albino rats (32) were used in the study. Patches (1 x 2 mm) for vascular grafts were prepared. Three groups were tested: group 1 (n = 12; tranilast coated), group 2 (n = 10; adhesive-only film-layer-coated), and group 3 (n = 10; normal ePTFE patch grafts sutured to the carotid arteries of the rats). Recipient sites of the carotid arteries were excised 4 weeks after surgery. All sections were examined histologically for graft patency, thrombus formation, and neointimal thickness. Expression of PDGF, fibroblast growth factor, and TGF-beta1 on cross-sections of the neointima were evaluated by immunohistochemistry. No significant differences were found regarding mean neointimal thicknesses. PDGF and TGF-beta-1 expressions were significantly lower in group 1. Although a decrease in local effect of tranilast was observed for growth factor expressions at a drug concentration of 0.05 mg/cm(2), a significant reduction in neointimal hyperplasia was not achieved. The coating concentration of 0.05 mg/cm(2) may have been too low to produce an antiproliferative effect. Given our promising results, further studies are recommended and planned using different drug concentrations and time intervals.  相似文献   
6.
A neurotrophic model for stress-related mood disorders.   总被引:31,自引:0,他引:31  
There is a growing body of evidence demonstrating that stress decreases the expression of brain-derived neurotrophic factor (BDNF) in limbic structures that control mood and that antidepressant treatment reverses or blocks the effects of stress. Decreased levels of BDNF, as well as other neurotrophic factors, could contribute to the atrophy of certain limbic structures, including the hippocampus and prefrontal cortex that has been observed in depressed subjects. Conversely, the neurotrophic actions of antidepressants could reverse neuronal atrophy and cell loss and thereby contribute to the therapeutic actions of these treatments. This review provides a critical examination of the neurotrophic hypothesis of depression that has evolved from this work, including analysis of preclinical cellular (adult neurogenesis) and behavioral models of depression and antidepressant actions, as well as clinical neuroimaging and postmortem studies. Although there are some limitations, the results of these studies are consistent with the hypothesis that decreased expression of BDNF and possibly other growth factors contributes to depression and that upregulation of BDNF plays a role in the actions of antidepressant treatment.  相似文献   
7.
8.
BACKGROUND: We aimed to determine whether serum concentrations of anti-Müllerian hormone (AMH) can be used as a tool for prediction of the efficacy of sperm retrieval. METHODS: This was a prospective cohort observational study. AMH levels were determined in 47 men presenting for infertility evaluation. Group 1 consisted of 24 infertile patients diagnosed with non-obstructive azoospermia. Group 1 was further divided into two subgroups. The patients with spermatozoa in their testicular samples constituted group 1a (n = 13), while the patients with absence of spermatozoa constituted group 1b (n = 11). Twenty-three normozoospermic fertile men constituted group 2. Serum AMH was measured before obtaining testicular specimens. RESULTS: Testicular spermatozoa were recovered in 13 out of the 24 patients (54%). Demographic characteristics of the three groups were similar. The difference between serum AMH levels among the three groups did not reach statistical significance. CONCLUSIONS: We speculated that although AMH is secreted predominantly into the seminiferous tubules, studying serum samples might be more advantageous than seminal plasma because the presence of seminal proteases could influence AMH levels in the latter. However, our results did not demonstrate differences in serum concentrations of AMH between the studied groups. Studies with extended patient populations focusing on seminal plasma concentrations of AMH are warranted.  相似文献   
9.
The purpose of this study was to present our experience with combined use of CO2 laser and cold instrumentation for Reinke’s edema surgery and to evaluate 1-year follow-up results of the technique in a series of professional voice users. Fifteen patients with Reinke’s edema who underwent microlaryngoscopic surgery were included. Videolaryngostroboscopy, perceptual and acoustic voice analyses were performed before and after surgery. During the 1-year follow-up, no recurrence of Reinke’s edema was encountered. Significant postoperative improvement was obtained in the quality of voice, in terms of GRBAS scores, Fo, jitter, shimmer and NHR. No evidence of laryngeal cancer was found on the histological examinations. Combined use of CO2 laser and cold instrumentation provides a reliable and safe method for Reinke’s edema surgery, and cessation of smoking, voice rest and control of the laryngopharyngeal reflux contribute to the success of surgery. We consider that the removal of redundant mucosa of the vocal fold reduces the risk of the recurrence of Reinke’s edema and provides better quality of voice. However, it does not imply that our method is superior to others’, but this procedure constitutes an effective treatment of choice for Reinke’s edema patients, including professional voice users.  相似文献   
10.
We present the case of a patient with juvenile onset systemic lupus erythematosus (SLE) who developed a persistent, acquired hypogammaglobulinaemia with IgG deficiency. The hypogammaglobulinaemia was probably a complication of high dose corticosteroid treatment. The serum IgG level remained subnormal despite intravenous immunoglobulin therapy. Lupus vulgaris, which developed on the nasal cartilage in this patient with SLE, is not an expected finding. This patient is probably the first reported case of SLE associated with lupus vulgaris.  相似文献   
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