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51.

Background

Tranexamic acid is used to treat pigmented disorder in dermatology for a long time however there are limited data for effectiveness of tranexamic acid for rejuvenation and improvement of wrinkle. Here we want to find the effectiveness of tranexamic acid as mesotherapy in improvement of periorbital wrinkle in a clinical trial study.

Methods

Patients with melasma who were treated with 4 session of tranexamic acid mesotherapy at intervals on 1 week were evaluated with Visioface device before starting and 1 month after last course of treatment. The outcomes including volume, area, area percent, and depth were measured by Visioface device.

Results

Mean of periorbital wrinkles volume before and after procedure were 89 271 and 74 639 pixel3 (px3), respectively. Very significant difference with p-value of <0.001 was detected at volume of patient wrinkles before and after treatment. Moreover, the mean of area (and area percent) of their periorbital wrinkles before and after therapeutic method were 8481 Px3 (1.131%) and 7184 Px3 (0.646%), respectively, with significant differences (both have p-value of <0.001).Mean of periorbital wrinkles depth at before and after treatment were 9.8 and 9.6, respectively, without remarkable difference (p-value was 0.257).

Conclusion

Tranexamic acid mesotherapy significantly leads to reduced volume and area of wrinkles. Injection of tranexamic acid as mesotherapy seems to be effective in improvement of periorbital wrinkling.  相似文献   
52.
53.
Neurodevelopmental delay and intellectual disability (ID) can arise from numerous genetic defects. To date, variants in the EXOSC gene family have been associated with such disorders. Using next-generation sequencing (NGS), known and novel variants in this gene family causing autosomal recessive ID (ARID) have been identified in five Iranian families. By collecting clinical information on these families and comparing their phenotypes with previously reported patients, we further describe the clinical variability of ARID resulting from alterations in the EXOSC gene family, and emphasize the role of RNA processing dysregulation in ARID.  相似文献   
54.
OBJECTIVE: To assess the roles of the interleukin 4 (IL-4) and interferon-g (IFN-g) gene polymorphisms in a series of patients with biopsy-proven giant cell arteritis (GCA). METHODS: Eighty-two patients with biopsy-proven GCA and 102 ethnically matched controls from the Lugo region (Northwest Spain) were studied. The following single nucleotide polymorphisms (SNP) were assessed: IL-4 (SNP1: rs2070874, SNP2: rs2227284, SNP3: rs2227282, SNP4: rs2243266, and SNP5: rs2243267) and IFN-g (SNP1: rs1861494, SNP2: rs1861493, and SNP3: rs2069718). RESULTS: Significant differences in allele and genotype frequencies were observed for the IL-4 SNP between HLA-DRB1*04 negative patients and controls. Epistatic interaction between SNP2 (rs2227284) with HLA-DRB1 showed a significant interaction (p = 0.001) and carriage of the SNP2*T allele in the absence of HLA-DRB1*04 resulted in a 4-fold risk of developing GCA (OR 4.2, 95% CI 1.1-15.6). Also, a significant increase in the frequency of the T-T-C-A-C IL-4 haplotype was observed in HLA-DRB1*04 negative GCA patients compared to the controls (p = 0.02; OR 2.0, 95% CI 1.0-3.9). Similar distributions of allele and genotype frequencies were observed for the IFN-g polymorphisms in both GCA patients and controls. CONCLUSION: Our results suggest an association with IL-4 gene polymorphism that is dependent on HLA-DRB1 genotype in GCA susceptible individuals. These data indicate an interaction between HLA-DRB1 and IL-4 that contributes to pronounced disease susceptibility.  相似文献   
55.
56.

Background

As one of the most common work-related musculoskeletal disorders and postural deviations, forward head posture (FHP), is considered to lead to muscle imbalance.

Objectives

The aim of this study is to investigate the bilateral cross-sectional area (CSA) of the deep neck flexor muscles at rest and during five stages of the craniocervical flexion (CCF) test in individuals with FHP and the controls with normal head posture.

Methods

Eighteen students with FHP and 18 controls with normal head posture, all females aged 18–35 years, participated in this study. Participants were categorized into two groups based on their craniovertebral angle. The CSA of the deep neck flexors was measured using ultrasonography while participants lay supine on the table with a pressure biofeedback unit placed under their necks in order to let the examiner measure the CSA of the muscles during rest and five stages of the CCF test including 22, 24, 26, 28, and 30 mmHg of the pressure biofeedback unit.

Results

A significant effect of contraction level was observed in both groups, indicating significant increases of the CSA of the deep neck flexors during contraction (F = 64.37, P < 0.001). No significant difference was evident for the CSA of the deep neck flexors between the groups, although the increase in the CSA of the deep neck flexors was up to 28 mmHg in the normal head posture group compared to 26 mmHg in the FHP group.

Conclusions

The results of the present study showed no significant difference between the performance of the deep neck flexors during the CCF test in FHP and normal head posture individuals, which challenge the common belief of the deep neck flexors weakness in individuals sustaining FHP.  相似文献   
57.

Purpose

Ultrasound imaging is an effective approach for diagnosing breast cancer, but it is highly operator-dependent. Recent advances in computer-aided diagnosis have suggested that it can assist physicians in diagnosis. Definition of the region of interest before computer analysis is still needed. Since manual outlining of the tumor contour is tedious and time-consuming for a physician, developing an automatic segmentation method is important for clinical application.

Methods

The present paper represents a novel method to segment breast ultrasound images. It utilizes a combination of region-based active contour and neutrosophic theory to overcome the natural properties of ultrasound images including speckle noise and tissue-related textures. First, due to inherent speckle noise and low contrast of these images, we have utilized a non-local means filter and fuzzy logic method for denoising and image enhancement, respectively. This paper presents an improved weighted region-scalable active contour to segment breast ultrasound images using a new feature derived from neutrosophic theory.

Results

This method has been applied to 36 breast ultrasound images. It generates true-positive and false-positive results, and similarity of 95%, 6%, and 90%, respectively.

Conclusion

The purposed method indicates clear advantages over other conventional methods of active contour segmentation, i.e., region-scalable fitting energy and weighted region-scalable fitting energy.
  相似文献   
58.
OBJECTIVE: Giant cell arteritis (GCA) is the most frequent vasculitis in European and North American countries. Increased expression of monocyte chemoattractant protein 1 (MCP-1) has been observed within the inflammatory infiltrates of blood vessels and serum of patients with GCA and in other autoimmune and inflammatory conditions. MCP-1 gene polymorphisms have been reported to contribute to susceptibility to several immune and inflammatory conditions. To investigate the clinical implication of MCP-1 polymorphisms in GCA, we examined the association of 3 single nucleotide polymorphisms (SNP) in a series of patients with GCA from Northwest Spain. METHODS: Seventy-nine patients with biopsy proven GCA and 99 ethnically matched controls were studied. Patients and controls were genotyped for MCP-1 polymorphisms. SNP included in this study (rs2857657, rs4586, rs139000) were located in intron 1(G/C), exon 2(T/C), and 3'UTR(C/T) region of MCP-1 gene. RESULTS: The distribution of the alleles and genotypes for each MCP-1 polymorphism showed no significant differences between GCA patients and controls. When we compared the overall distribution of haplotype frequencies between GCA cases and controls a significant difference was observed (p = 0.005, by chi-square test from 4 2 contingency table). In addition, haplotype C-C was significantly increased in GCA patients compared with controls (p = 0.03, OR 2.09, 95% CI 1.09-4.02). Similarly, haplotype T-T was overrepresented in GCA patients (p = 0.005). CONCLUSION: Significant differences in haplotype frequencies between GCA patients and controls may indicate a role for MCP-1 gene in susceptibility to GCA.  相似文献   
59.
Despite the abundance of skin substitutes in the worldwide market, major hurdles in developing more complex tissues include the addition of skin appendages and vascular networks as the most important structure. The aim of this research was a clinical feasibility study of a novel prevascularized skin grafts containing the dermal and epidermal layer using the adipose stromal vascular fraction (SVF)‐derived endothelial cell population for vascular network regeneration. Herein, we characterized hydrogel with emphasis on biological compatibility and cell proliferation, migration, and vitality. The therapeutic potential of the prevascularized hydrogel transplanted on five human subjects as an intervention group with diabetic wounds was compared with nonvascularized skin grafts as the control on five patients. Wound planimetric and biometric analysis was performed using a Mann–Whitney nonparametric t‐test (p ≤ .05). The fibrin–collagen hydrogel was suitable for skin organotypic cell culture. There was a significant (p ≤ .05) increased in skin thickness and density in the vascular beds of the hypodermis measured with skin scanner compared with that in the control group. No significant macroscopic differences were observed between the intervention and control groups (p ≤ .05). In summary, we report for the first time the use of autologous dermal–epidermal skin grafts with intrinsic vascular plexus in a clinical feasibility study. The preliminary data showed that SVF‐based full‐thickness skin grafts are safe and accelerate the wound healing process. The next stage of the study is a full‐scale randomized clinical trial for the treatment of patients with chronic wounds.  相似文献   
60.
To evaluate the influence of echocardiographic examination in the clinical management of the sick neonate, 241 patients, admitted to the neonatal intensive care unit of a tertiary referral center that had echocardiograms with data available for review, were enrolled in a retrospective study. Asymptomatic murmurs (45%) followed by extracardiac anomalies/dysmorphic features (24%) were the most common clinical indications for requesting an echocardiogram. Congenital structural abnormalities (33%), hemodynamically significant patent arterial duct (3%), persistent pulmonary hypertension of the newborn (6%), and left ventricular dysfunction (3%) were the echocardiographic findings that subgrouped as structural or functional abnormalities. Patent oval foramen and hemodynamically nonsignificant patent arterial duct (20%) and physiologic pulmonary artery stenosis (1%) were categorized as normal structural group. Thirty‐four percent of neonates had normal heart anatomy. This investigation changed the clinical management in at least 66% of newborns scanned, including emergency surgical intervention for 7%, medical treatment for 22%, and routine cardiologic follow‐up for 37% of patients. Asymptomatic murmur in our critically ill neonates has been associated with a higher incidence of cardiac disease. Hence, echocardiography is an important tool for diagnosis of cardiac abnormalities that can influence the management and outcome of the sick newborn in the intensive care unit. A preliminary echocardiogram performed by the neonatologist under the supervision of a pediatric cardiologist for interpretation and review is an alternate when there is not a cardiologist “in house.”  相似文献   
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