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Background

Despite facet joints being three-dimensional structures, previous computed tomography and magnetic resonance imaging studies have evaluated facet joint orientation in only the axial plane. Facet joint orientation in the sagittal plane has rarely been studied using these imaging techniques. The aim of this study was to elucidate facet joint orientation in both the axial and sagittal planes on computed tomography.

Methods

A total of 568 patients (343 men, 225 women) (excluding orthopedic outpatients) for whom abdominal and pelvic computed tomography scans were obtained at our hospital between September 2010 and October 2012 were included. Mean age was 63 (range 21–90) years. Patients were divided into a degenerative spondylolisthesis group (67 patients; 30 men, 37 women) and a control group (313 patients; 313 men, 188 women). Facet joint orientation was evaluated in the control group according to patient age (≤50, 51–60, 61–70, or ≥71 years). The findings in the control group were then compared with those in the degenerative spondylolisthesis group. The orientation of the lumbar facet joints at each level was measured in the axial and sagittal planes on computed tomography images.

Results

Facet joint angles decreased with age at L4/5 and L5/S1 in women in the axial plane and at L4/5 in men and L3/4 and L4/5 in women in the sagittal plane. The variation in facet joint angle was greatest at L4/5 in women. Patients with degenerative spondylolisthesis showed more sagittally and horizontally oriented facet joints in the axial and sagittal planes; facet tropism showed an association with degenerative spondylolisthesis in the axial plane.

Conclusions

The axial and sagittal orientation of facet joints in the lower lumbar vertebra, especially L4/5, was negatively correlated with age. This finding could help to explain why older people are more prone to degenerative spondylolisthesis.  相似文献   
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PurposeTo investigate differences in outcomes of uterine artery embolization (UAE) for leiomyoma when performed during different phases of the menstrual cycle.Materials and MethodsIn this single-institution retrospective analysis, 111 premenopausal patients (median [range] age, 44 [33–52] years) undergoing UAE for symptomatic leiomyoma between June 2014 and February 2020 were included. Twenty-one patients underwent UAE in the menstrual phase (the early follicular phase), 27 in the late follicular phase, and 63 in the luteal phase. Baseline characteristics and technical and peri-procedural outcomes were compared among groups. Leiomyoma infarction on contrast-enhanced magnetic resonance imaging 1 week after UAE and 4-month outcomes, including changes in the Uterine Fibroid Symptom and Quality of Life questionnaire scores, the volume reduction rates of the uterus and largest leiomyoma, follicle stimulating hormone values, adverse events, and amenorrhea, were compared among groups.ResultsA 4-month follow-up was completed for all patients. No significant differences were observed among groups in baseline characteristics or technical and peri-procedural outcomes. There were no significant differences in the multivariate-adjusted 1-week infarction rates of all leiomyoma volumes (P = .161) or multivariate-adjusted 4-month outcomes, including changes in the Uterine Fibroid Symptom and Quality of Life questionnaire symptoms and total scores (P = .864 and P = .798, respectively), the volume reduction rates of the uterus and the largest leiomyoma (P = .865 and P = .965, respectively), and follicle stimulating hormone values (P = .186) among the groups. No significant differences were noted in the 4-month adverse events (P = .260) or amenorrhea (P = .793) among the groups.ConclusionsThe present study demonstrated no significant differences in the outcomes of UAE for leiomyoma when performed during different phases of the menstrual cycle.  相似文献   
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Plasminogen activator inhibitor (PAI)-1 is predictive of poor outcome in several types of cancer. The present study investigated the biological role for PAI-1 in ovarian cancer and potential of targeted pharmacotherapeutics. In patients with ovarian cancer, PAI-1 mRNA expression in tumor tissues was positively correlated with poor prognosis. To determine the role of PAI-1 in cell proliferation in ovarian cancer, the effects of PAI-1 inhibition were examined in PAI-1-expressing ovarian cancer cells. PAI-1 knockdown by small interfering RNA resulted in significant suppression of cell growth accompanied with G2/M cell cycle arrest and intrinsic apoptosis. Similarly, treatment with the small molecule PAI-1 inhibitor TM5275 effectively blocked cell proliferation of ovarian cancer cells that highly express PAI-1. Together these results suggest that PAI-1 promotes cell growth in ovarian cancer. Interestingly, expression of PAI-1 was increased in ovarian clear cell carcinoma compared with that in serous tumors. Our results suggest that PAI-1 inhibition promotes cell cycle arrest and apoptosis in ovarian cancer and that PAI-1 inhibitors potentially represent a novel class of anti-tumor agents.  相似文献   
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Salivary duct carcinoma (SDC) is a distinctive and aggressive neoplasm. The most frequent site of origin is the parotid gland, followed by the submandibular gland. SDC originating in the minor salivary glands, particularly in the ectopic glands within the mandible, is extremely rare. We describe a 62-year-old man with SDC in the mandible, who presented with a painless lump in the right submandibular region (later identified as lymph node metastasis) and ipsilateral mental nerve palsy. Histologic examination after ablative surgery revealed SDC originating in the mandible and cervical nodal metastases spreading to levels I-III. The patient remains alive 59 months after presentation as a result of postoperative full-dose irradiation and regular intensive chemotherapy using TXT, 5-FU, and CDDP. However, the patient has local recurrence and distant metastases to the lung and brain. In this report, we also discuss the specific diagnostic criteria and developmental theories of intraosseous salivary gland tumors.  相似文献   
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Objective

Heat shock during restorative procedures can trigger damage to the pulpodentin complex. While severe heat shock has toxic effects, fever-range heat stress exerts beneficial effects on several cells and tissues. In this study, we examined whether continuous fever-range heat stress (CFHS) has beneficial effects on thermotolerance in the rat clonal dental pulp cell line with odontoblastic properties, KN-3.

Methods

KN-3 cells were cultured at 41 °C for various periods, and the expression level of several proteins was assessed by Western blot analysis. After pre-heat-treatment at 41 °C for various periods, KN-3 cells were exposed to lethal severe heat shock (LSHS) at 49 °C for 10 min, and cell viability was examined using the MTS assay. Additionally, the expression level of odontoblast differentiation makers in surviving cells was examined by Western blot analysis.

Results

CFHS increased the expression levels of several heat shock proteins (HSPs) in KN-3 cells, and induced transient cell cycle arrest. KN-3 cells, not pre-heated or exposed to CFHS for 1 or 3 h, died after exposure to LSHS. In contrast, KN-3 cells exposed to CFHS for 12 h were transiently lower on day 1, but increased on day 3 after LSHS. The surviving cells expressed odontoblast differentiation markers, dentine sialoprotein and dentine matrix protein-1. These results suggest that CFHS for 12 h improves tolerance to LSHS by inducing HSPs expression and cell cycle arrest in KN-3 cells.

Conclusions

The appropriate pretreatment with continuous fever-range heat stress can provide protection against lethal heat shock in KN-3 cells.  相似文献   
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