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961.
A prospective and controlled study of training after surgery for lumbar disc herniation (LDH). The objective was to determine the effect of early neuromuscular customized training after LDH surgery. No consensus exists on the type and timing of physical rehabilitation after LDH surgery. Patients aged 15–50 years, disc prolapse at L4–L5 or L5–S1. Before surgery, at 6 weeks, 4, and 12 months postoperatively, the following evaluations were performed: low back pain and leg pain estimated on a visual analog scale, disability according to the Roland–Morris questionnaire (RMQ) and disability rating index (DRI). Clinical examination, including the SLR test, was performed using a single blind method. Consumption of analgesics was registered. Twenty-five patients started neuromuscular customized training 2 weeks after surgery (early training group=ETG). Thirty-one patients formed a control group (CG) and started traditional training after 6 weeks. There was no significant difference in pain and disability between the two training groups before surgery. Median preoperative leg pain was 63 mm in ETG and 70 mm in the CG. Preoperative median disability according to RMQ was 14 in the ETG and 14.5 in the CG. Disability according to DRI (33/56 patients) was 5.3 in the ETG vs. 4.6 in the CG. At 6 weeks, 4 months, and 12 months, pain was significantly reduced in both groups, to the same extent. Disability scores were lower in the ETG at all follow-ups, and after 12 months, the difference was significant (RMQ P=.034, DRI P=.015). The results of the present study show early neuromuscular customized training to have a superior effect on disability, with a significant difference compared to traditional training at a follow-up 12 months after surgery. No adverse effects of the early training were seen. A prospective, randomized study with a larger patient sample is warranted to ultimately demonstrate that early training as described is beneficial for patients undergoing LDH surgery.  相似文献   
962.
Background Congenital pseudarthrosis of the tibia (CPT) is frequently, but not always, associated with neurofibromatosis type 1 (NF1). Double inactivation of the NF1 gene has been reported to be the pathogenesis of CPT in NF1 cases. Methods We analyzed the loss of heterozygosity (LOH) of the NF1 gene in cases of CPT with NF1 to examine whether double inactivation was seen in the case. In addition to morphological analysis, immunoexpression of differentiation markers was examined. Results and discussion The tibia tapered with the zone phenomenon from mature to immature bone with osteoblastic rimming, resembling osteofibrous dysplasia. Osteosclerotic bowed bone with a small number of osteoclasts suggested dysfunction of bone remodeling. Fibrous tissue at the site of pseudarthrosis was associated with the periosteum and demonstrated myofibroblastic differentiation accompanied by massive cartilage formation, suggesting some misdirection during the differentiation of periosteum to myofibroblasts or chondrocytes. LOH of the NF1 gene locus was not seen in fibrous tissue. This result suggests that CPT is not accompanied by double inactivation in every NF1 case.  相似文献   
963.
964.
A biomechanical study comparing simulated lytic vertebral metastases treated with laser-induced thermotherapy (LITT) and vertebroplasty versus vertebroplasty alone. To investigate the effect of tumor ablation using LITT prior to vertebroplasty on biomechanical stability and cement fill patterns in a standardized model of spinal metastatic disease. Vertebroplasty in the metastatic spine is aimed at reducing pain, but is associated with risk of cement extravasation in up to 10%. Six pairs of fresh-frozen cadaveric thoracolumbar spinal motion segments were tested in axial compression intact, with simulated metastases and following percutaneous vertebroplasty with or without LITT. Canal narrowing under load, pattern of cement fill, load to failure, and LITT temperature and pressure generation were collected. In all LITT specimens, cement filled the defect without extravasation. The canal extravasation rate was 33% in specimens treated without LITT. LITT and vertebroplasty yielded a trend toward improved posterior wall stability (P = 0.095) as compared to vertebroplasty alone. Moderate rises in temperature and minimal pressure generation was seen during LITT. In this model, elimination of tumor by LITT, facilitates cement fill, enhances biomechanical stability and reduces the risk of cement extravasation.  相似文献   
965.
Fifteen skeletally immature patients with double major adolescent idiopathic scoliosis with large lumbar curves and notable L4 and L5 coronal plane obliquity were retrospectively studied. Seven patients who underwent anterior release and fusion of the lumbar curve with segmental anterior instrumentation and subsequent posterior instrumentation ending at L3 were compared with eight patients treated with anterior release and fusion without anterior instrumentation followed by posterior instrumentation to L3 or L4. At 4.5 years follow-up (range 2.5-7 years), curve correction, coronal balance and fusion rate were not statistically different between the two groups; however, the group with anterior instrumentation had improved coronal plane, near normalangulation in the distal unfused segment compared with the group without anterior instrumentation. In cases involving severe lumbar curvatures in the context of double major scoliosis, when as a first stage anterior release is chosen, the addition of instrumentation appears to restore normal coronal alignment of the distal unfused lumbar segment, and may in certain cases save a level compared with traditional fusions to L4.  相似文献   
966.
OBJECTIVE: Respiratory scleroma (RS) is a progressive, chronic, granulomatous disease caused by Klebsiella rhinoscleromatis. There is only one report of RS association with HLA-DQ3. In this study, molecular association of HLA class II and RS was determined. STUDY DESIGN AND SETTING: Nine RS patients and 163 healthy controls were compared. DQA1, DQB1, and DRB1 loci were typed. RESULTS: Statistical analysis demonstrated association between DQB1*0301 and susceptibility to RS (P(c) = 0.004). Haplotype analysis showed an association of DQA1*03011-DQB1*0301 (P = 1.21E-19) and DRB1*0407-DQA1*03011-DQB1*0301 (P = 0.0002). CONCLUSIONS: Results established that DQA1*03011-DQB1*0301 haplotype is a strong risk factor for development of RS.  相似文献   
967.

Background  

Official guidelines that promote evidence-based and cost-effective prescribing are of main relevance for obvious reasons. However, to what extent these guidelines are followed and their conditioning factors at different levels of the health care system are still insufficiently known.  相似文献   
968.
This study explored the toxic effects of crotoxin isolated from Crotalus durissus cumanensis venom on the ultrastructure of mice cardiac autonomic nervous system. Mice were intravenously injected with saline (control group) and crotoxin diluted in saline venom (study group) at a dose of 0.107 mg/kg mouse body weight. Samples from the inter-ventricular septum were prepared for electron microscopy after 6 h (G1), 12 h (G2), 24 h (G3) and 48 h (G4). The G1 group showed some cardiomyocyte with pleomorphic mitochondria. Capillary swollen walls, nerve cholinergic endings with depleted acetylcholine vesicles in their interior and other depletions were observed. A space completely lacking in contractile elements was noticed. The G2 group demonstrated a myelinic figure, a subsarcolemic region with few myofibrils and nervous cholinergic terminal with scarce vacuoles in their interior. The G3 group demonstrated a structure with a depleted axonic terminal, mitochondrias varying in size and enhanced electron density. In addition, muscular fibers with myofibrillar structure disorganization, a depleted nervous structure surrounded by a Schwann cell along with an abundance of natriuretic peptides, were seen. An amyelinic terminal with depleted Schwann cell and with scarce vesicles was also observed. Finally, axonic lysis with autophagic vacuoles in their interior and condensed mitochondria was observed in the G4 group. This work describes the first report of ultrastructural damage caused by crotoxin on mice cardiac autonomic nervous system.  相似文献   
969.
The carotid rete of Artiodactyla, an intracranial arterial plexus which supplies blood to the brain, has intrigued investigators for a long time. This study was designed to examine the responsiveness of isolated retial arteries (250-700 microns in external diameter) of goat, pig, and cattle. The findings in these arteries were compared to those observed in cerebral arteries (250-650 microns in external diameter) of the same animal species. The magnitude of the arterial responses to potassium chloride varied with the resting tension applied to the tissue. The two types of vessels exhibited similar resting tension values (0.3 g) for maximal tension development in response to potassium chloride; however, the ability of retial vessels to contract in the presence of potassium chloride was consistently smaller than that of cerebral arteries. The contractile response of retial arteries to norepinephrine (10(-9) to 10(-4) M), tyramine (10(-8) to 10(-3) M), and field electrical stimulation (2-16 Hz) was negligible. The same retial arteries exhibited dose-dependent contractions in response to 5-hydroxytryptamine (10(-9) to 10(-5) M) and histamine (10(-9) to 3 X 10(-4) M). Cerebral arteries exhibited larger responses to the vasoactive agents than retial arteries. Our findings indicate that retial arteries have a small vasomotor activity in response to adrenergic stimulation or to vasoactive agents. Therefore, the carotid rete of Artiodactyla may have a low ability to change resistance to blood flow under neural or hormonal influences.  相似文献   
970.
In a small company, the whole company culture, including the management style, is dominated by the owner. The management culture in small companies and above all the management style of the owner determine the chances of successfully introducing workplace health promotion (WHP). For this reason a typology was developed that describes the management personalities who affect the company culture in small enterprises. This provides a guide to the possible success of WHP in connection with the management style. Although a summary of the management and corporate culture of small companies in a few categories cannot show the variety of social reality, it can provide orientation. The typical categories of company social order (a mixture of ownership and leadership) in small and medium-sized enterprises are given below. Furthermore, there is an assessment of what the chances of realising workplace health promotion are in each type of company. Small and medium-sized companies (SME) have a number of organisational characteristics which are just ideal for the introduction and implementation of workplace health promotion. The work of the employer and employees is often the same. Information in the company is generally comprehensive and easily available. The lack of information which employees often complain about in large companies is not a problem. There is a good flow of communication. Small companies have a flat hierarchy that enables participation, the essential requirement for WHP. There is a close social relationship between the company head and the workforce, although it must be said that this closeness can be dangerous, particularly if it is misused as complete social control. The readiness to implement Workplace Health Promotion (WHP) in SME and the degree of success depends largely on the personality of the company manager and the style of leadership. Considering the importance of a manager’s personality for WHP in SME, modules and instruments to assist company owners and managers in SME are to be developed. On behalf of and in co-operation with the Austrian Network for Workplace Health Promotion several modules have been introduced to assist owners and managers of SMEs.  相似文献   
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