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1.
Freiberg's infraction is an ostechondrosis of a lesser metatarsal head resulting in degeneration of the metatarsophalangeal joint. Several mechanisms have been suggested in its pathenogenesis. Freiberg first described the entity and believed single impact trauma was the underlying cause. Repetitive biomechanical microtrauma is the most widely accepted etiologic theory. Other factors contributing to its development include aseptic necrosis, ischemia, and a congenital predisposition. We present a case report of Freiberg's infraction occurring in identical twins involving multiple metatarsals in various stages of degeneration. One of the twins was affected unilaterally whereas the other twin was affected bilaterally. Both twins had involvement of the second metatarsal on the same side extremity. The occurrence of Freiberg's infraction in identical twins suggests that an underlying congenital predisposition to the condition may play more of a role than previously considered.  相似文献   
2.
The objective of this study was to elucidate gene and protein expression of Wnt signaling molecules in chondrocytes of foals having early osteochondrosis (OC) versus normal controls. The hypothesis was that increased expression of components of Wnt signaling pathway in osteochondral junction (OCJ) and cartilage canal (CC) chondrocytes would be found in early OC when compared to controls. Paraffin‐embedded osteochondral samples (7 OC, 8 normal) and cDNA from whole cartilage (7 OC, 10 normal) and chondrocytes surrounding cartilage canals and osteochondral junctions captured with laser capture microdissection (4 OC, 6 normal) were obtained from femoropatellar joints of 17 immature horses. Equine‐specific Wnt signaling molecule mRNA expression levels were evaluated by two‐step real‐time qPCR. Spatial tissue protein expression of β‐catenin, Wnt‐11, Wnt‐4, and Dkk‐1 was determined by immunohistochemistry. There was significantly decreased Wnt‐11 and increased β‐catenin, Wnt‐5b, Dkk‐1, Lrp6, Wif‐1, Axin1, and SC‐PEP gene expression in early OC cartilage canal chondrocytes compared to controls. There was also significantly increased β‐catenin gene expression in early OC osteochondral junction chondrocytes compared to controls. Based on this study, abundant gene expression differences in OC chondrocytes surrounding cartilage canals suggest pathways associated with catabolism and inhibition of chondrocyte maturation are targeted in early OC pathogenesis. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1433–1438, 2015.  相似文献   
3.
Cartilage canal vessels in epiphyseal cartilage have a pivotal role in the pathogenesis of osteochondrosis/osteochondritis dissecans. The present study aimed to validate high field magnetic resonance imaging (MRI) methods to visualize these vessels in young pigs. Osteochondral samples from the distal femur and distal humerus (predilection sites of osteochondrosis) of piglets were imaged post‐mortem: (1) using susceptibility‐weighted imaging (SWI) in an MRI scanner, followed by histological evaluation; and (2) after barium perfusion using µCT, followed by clearing techniques. In addition, both stifle joints of a 25‐day‐old piglet were imaged in vivo using SWI and gadolinium enhanced T1‐weighted MRI, after which distal femoral samples were harvested and evaluated using µCT and histology. Histological sections were compared to corresponding MRI slices, and three‐dimensional visualizations of vessels identified using MRI were compared to those obtained using µCT and to the cleared specimens. Vessels contained in cartilage canals were identified using MRI, both ex vivo and in vivo; their locations matched those observed in the histological sections, µCT images, and cleared specimens of barium‐perfused tissues. The ability to visualize cartilage canal blood vessels by MRI, without using a contrast agent, will allow future longitudinal studies to evaluate their role in developmental orthopedic disease. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31:2006–2012, 2013  相似文献   
4.
Focal ischemic chondronecrosis of epiphyseal growth cartilage (EGC) during endochondral ossification is believed to be a key early event on the pathway to osteochondrosis (OC) in both animals and humans. The lateral ridge of the equine trochlea is a site where severe osteochondritis dissecans lesions frequently arise and is a model for the study of naturally occurring disease. Non‐invasive imaging to investigate EGC vascularity may help elucidate why focal ischemia occurs. 3T MRI susceptibility‐weighted imaging (SWI) of femoral trochlea of OC predisposed (n = 10) and control (n = 6) day‐old foals, with minimal joint loading after birth, was performed. SWI and 3D images revealed the EGC vascular architecture without a contrast agent, and matched histologic observations. No vascular lesions were identified. There was no difference in the vascular density and architecture between control and OC specimens, but a striking difference in vascular pattern was seen at the OC‐predilected site in the lateral ridge of the trochlea in all specimens, when compared to the medial ridge of the trochlea, where OC lesions are rarely observed. This site was less ossified with more perichondrial vessels not yet bridging with the subchondral bone. Furthermore, the mean vascular density of all specimens was significantly higher at this site. We speculate that joint morphology and focal internal trauma on this site with a unique vascular architecture may trigger ischemic events at this site. SWI permitted visualization of EGC in young foals with a clinical 3T MRI and paves the way for non‐destructive longitudinal studies to improve understanding of OC in all species. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1539–1546, 2016.  相似文献   
5.
We propose an experimental model of degenerative-dystrophic changes in intervertebral disks of rat tail. The results of X-ray examination and histological studies showed that degenerative changes in the disk tissues caused by experimental compression of intervertebral disks in rat tails are identical to those in humans. __________ Translated from Kletochnye Tehnologii v Biologii i Medicine, No. 3, pp. 139–142, July, 2007  相似文献   
6.
OBJECTIVES—To investigate the relation with a case-control study between symptomatic osteochondrosis or spondylosis of the lumbar spine and cumulative occupational exposure to lifting or carrying and to working postures with extreme forward bending.
METHODS—From two practices and four clinics were recruited 229 male patients with radiographically confirmed osteochondrosis or spondylosis of the lumbar spine associated with chronic complaints. Of these 135 had additionally had acute lumbar disc herniation. A total of 197 control subjects was recruited: 107 subjects with anamnestic exclusion of lumbar spine disease were drawn as a random population control group and 90 patients admitted to hospital for urolithiasis who had no osteochondrosis or spondylosis of the lumbar spine radiographically were recruited as a hospital based control group. Data were gathered in a structured personal interview and analysed using logistic regression to control for age, region, nationality, and other diseases affecting the lumbar spine. To calculate cumulative forces to the lumbar spine over the entire working life, the Mainz-Dortmund dose model (MDD), which is based on an overproportional weighting of the lumbar disc compression force relative to the respective duration of the lifting process was applied with modifications: any objects weighing 5 kg were included in the calculation and no minimum daily exposure limits were established. Calculation of forces to the lumbar spine was based on self reported estimates of occupational lifting, trunk flexion, and duration.
RESULTS—For a lumbar spine dose >9×106 Nh (Newton×hours), the risk of having radiographically confirmed osteochondrosis or spondylosis of the lumbar spine as measured by the odds ratio (OR) was 8.5 (95% confidence interval (95% CI) 4.1 to 17.5) compared with subjects with a load of 0 Nh. To avoid differential bias, forces to the lumbar spine were also calculated on the basis of an internal job exposure matrix based on the control subjects' exposure assessments for their respective job groups. Although ORs were lower with this approach, they remained significant.
CONCLUSIONS—The calculation of the sum of forces to the lumbar spine is a useful tool for risk assessment for symptomatic osteochondrosis or spondylosis of the lumbar spine. The results suggest that cumulative occupational exposure to lifting or carrying and extreme forward bending increases the risk for developing symptomatic osteochondrosis or spondylosis of the lumbar spine.


Keywords: case-control study; physical work load; lumbar osteochondrosis; lumbar spondylosis  相似文献   
7.
Osteochondrosis is a condition involving defective endochondral ossification and retention of cartilage in subchondral bone. The pathophysiology of this condition is poorly characterized, but it has been proposed that the fundamental defect is failure of chondrocyte hypertrophy. The aim of the current study was to characterize phenotypic changes in chondrocytes associated with the initiation of osteochondrosis. Early lesions were induced in an equine model of osteochondrosis by feeding foals a high energy diet for 8 or 15 weeks. Lesions in articular‐epiphyseal growth cartilage were examined histologically and by quantitative PCR analysis of expression of a number of genes representative of pathways that regulate chondrocyte behavior during endochondral ossification. There were more cells present in clusters in the lesions compared to normal articular cartilage. Expression of matrix metalloproteinase‐13, type I collagen, type X collagen, and Runx2 mRNA was significantly greater in the lesions compared to normal cartilage from the same joint. Expression of vascular endothelial growth factor, type II collagen, connective tissue growth factor, aggrecan, Sox9, and fibroblast growth factor receptor 3 mRNA was not significantly different in lesions than in control cartilage. These observations suggest that osteochondrosis does not result from failure of chondrocytes to undergo hypertrophy. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 452–457, 2009  相似文献   
8.
目的:探讨胸腔镜辅助下侧前路减压融合术治疗胸腰段或高位腰椎间盘突出症(lumbar disc herniation,LDH)伴椎体后缘骨软骨病(vertebral osteochondrosis,VO)的可行性及其临床效果。方法:回顾性分析2017年12月至2019年12月采用胸腔镜辅助下侧前路减压融合术治疗胸腰段或高...  相似文献   
9.
Summary A number of case studies were followed for 10 years. Children suffering from postural defects, structural scoliosis and spinal osteochondrosis were separated from a normal group. Spinal mobility and posture were compared with the mobility of normal, healthy boys and girls aged 5–14 years. In postural defects curves similar to the physiologic one were observed. The range of motion was not physiologic in scoliosis. In this disease, rotationflexion thoracic hypermobility with decreased lumbar flexion ability was found. A physiologic trend was found in spinal osteochondrosis, although sometimes the rotational mobility of the spine was reduced. An extremely high increase of thoracic kyphosis was found only in children aged 14 years.  相似文献   
10.
In vivo visualization of subclinical osteochondrosis (OC) lesions, characterized by necrosis of epiphyseal growth cartilage, is necessary to clarify the pathogenesis of this disease. Hence, our objectives were to demonstrate induced necrosis of the epiphyseal cartilage in vivo using MRI and to monitor progression or resolution of resulting lesions. We also aimed to improve the goat model of OC by introducing controlled exercise. Vascular supply to the epiphyseal cartilage was surgically interrupted in four 5‐day‐old goats to induce ischemic cartilage necrosis in a medial femoral condyle. Starting 3 weeks postoperatively, goats underwent daily controlled exercise until euthanasia at 6, 10, 11 (n = 2) weeks postoperatively. T2 maps of operated and control femora were obtained in vivo at 3 (n = 4), 6 (n = 4), 9 (n = 3), and 11 (n = 2) weeks postoperatively using a 3 T MR scanner. In vivo MRI findings were validated against MRI results obtained ex vivo at 9.4 T in three goats and compared to histological results in all goats. Surgical interruption of the vascular supply caused ischemic cartilage necrosis in three out of four goats. T2 maps obtained in vivo at 3 T identified regions of increased relaxation time consistent with discrete areas of cartilage necrosis 3–11 weeks postoperatively and demonstrated delayed progression of the ossification front at 9 (n = 1) and 11 (n = 2) weeks postoperatively. In vivo MRI findings were confirmed by ex vivo MRI at 9.4 T and by histology. Identification of cartilage necrosis in clinical patients in the early stages of OC using T2 maps may provide valuable insight into the pathogenesis of this condition. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:868–875, 2017.
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