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1.
Summary The management of displaced intracapsular fractures of the hip is still controversial because of the high incidence of complications after internal fixation or hemiarthroplasty. To avoid some of these complications we have used primary total hip replacement for independently mobile patients over 65 years of age.Of 49 patients who were interviewed an average of 4.6 years after total hip replacement, 81.6% had excellent or good results as assessed by the Harris Hip Score. At that time two hips had been revised and another converted to Girdlestone due to deep infection. The survival of the prostheses was at 5 years 91.3%.It is concluded that total hip replacement is an established method of management for a selected group of patients with this injury, but further prospective studies are needed in order to define the groups of patients that benefit the most.  相似文献   
2.
Lethal white foal syndrome (LWFS) is a congenital anomaly of horses characterized by a white coat colour and aganglionosis of the bowel, which is similar to Hirschsprung disease (HSCR). We decided to investigate possible mutations of the endothelin-B receptor gene ( EDNRB ) in LWFS as recent studies in mutant rodents and some patients have demonstrated EDNRB defects. First, we identified a full-length cDNA for horse EDNRB . This cDNA fragment contained a 1329 bp open reading frame which encoded 443 amino acid residues. The predicted amino acid sequence was 89, 91 and 85% identical to human, bovine and mouse as well as rat EDNRB respectively, but only 55% identical to the human, bovine and rat endothelin A receptor (EDNRA). Secondly, sequence analysis, together with allele-specific PCR and the amplification- created restriction site (ACRS) technique, revealed a dinucleotide TC-- >AG mutation, which changed isoleucine to lysine in the predicted first transmembrane domain of the EDNRB protein. This was associated with LWFS when homozygous and with the overo phenotype when heterozygous.   相似文献   
3.
Objective To study the relationship between human leukocyte antigen (HLA)-DRB1 and DQ alleles and the genetic susceptibility of type 1 diabetes in North Chinese children. Methods Polymerase chain reaction (PCR) techniques were used to amplify the second exon of DRB1 and DQ alleles, after which sequence specific olignucleotide probe (SSOP) dot blot hybridization techniques were used to analyze the amplified products. Results DRB1*0301, DQA1*0301, DQB1*0201 alleles and DRB1*0301-DQA1*0501-DQB1*0201 haplotype were significantly increased in patients, while DQA1*0103 and DQB1*0601 alleles were significantly increased in controls. The distribution of DR4 and DR9 haplotypes in patients and controls were not significantly different, but DR3/DR4 and DR4/DR9 heterozygotes were significantly increased in patients. Conclusions DRB1*0301, DQA1*0301 and DQB1*0201 confer susceptibility while DQA1*0103 and DQB1*0601 confer protection to type 1 diabetes. DRB1*0301-DQA1*0501-DQB1*0201 haplotype offers a predisposition to type 1 diabetes in North Chinese. Although the distribution of DR4 and DR9 in patients and controls had no significant difference, DR3/DR4 and DR3/DR9 heterozygotes were significantly increased in patients, showing that the susceptive effects of DR3 and DR4 or DR4 and DR9 haplotypes could be added up.  相似文献   
4.
We report our clinical experience with phototherapy in 3802 infants; 3629 were exposed to "standard" daylight phototherapy and 173 to "high-intensity" blue-light phototherapy. High-intensity blue-light phototherapy was twice as effective as standard daylight phototherapy in decreasing bilirubin concentrations. No failures occurred with high-intensity phototherapy compared with an overall failure rate of 1.84/1000 with daylight lamps; these cases were transferred to high-intensity phototherapy with prompt response. Rebound after cessation of phototherapy was greater in those exposed to high-intensity blue light with a significantly greater number requiring a second exposure. However, the incidence was still low. No third exposure was required in any infant. Nursing of infants under high-intensity blue light was more difficult and inconvenient as was clinical monitoring. The light also caused more stress on the nursing and medical personnel. However, the infants tolerated both types of phototherapy equally well. High-intensity blue-light phototherapy would seem to be the treatment of choice for infants with rapidly increasing or very high bilirubin levels, as well as in those not responding adequately to daylight phototherapy.  相似文献   
5.
BACKGROUND: The informed consent procedure plays a central role in randomised controlled trials but has only been explored in a few studies on children. AIM: To assess the quality of the informed consent process in a paediatric setting. METHODS: A questionnaire was sent to parents who volunteered their child (230 children) for a randomised, double blind, placebo controlled trial of ibuprofen syrup to prevent recurrent febrile seizures. RESULTS: 181 (79%) parents responded. On average, 73% of parents were aware of the major study characteristics. A few had difficulty understanding the information provided. Major factors in parents granting approval were the contribution to clinical science (51%) and benefit to the child (32%). Sociodemographic status did not influence initial participation but west European origin of the father was associated with willingness to participate in future trials. 89% of participants felt positive about the informed consent procedure; however, 25% stated that they felt obliged to participate. Although their reasons for granting approval and their evaluation of the informed consent procedure did not differ, relatively more were hesitant about participating in future. Parents appreciated the investigator being on call 24 hours a day (38%) and the extra medical care and information provided (37%) as advantages of participation. Disadvantages were mainly the time consuming aspects and the work involved (23%). CONCLUSIONS: Parents' understanding of trial characteristics might be improved by designing less difficult informed consent forms and by the investigator giving extra attention and information to non-west European parents. Adequate measures should be taken to avoid parents feeling obliged to participate, rather than giving true informed consent.  相似文献   
6.
In a prospective study, 31 consecutive patients with a femoral shaft fracture were treated with the Marchetti-Vicenzi intramedullary flexible bundle-type nail. Open reduction of the fracture was necessary in 25 of the 31 patients (81%). Twenty-five of the 31 fractures (81%) united within 2.5 to 6 months after the operation (mean, 4.2 months). Nonunion occurred in one patient (3.2%). Other complications included delayed union in five patients (16%), femoral shortening in five (16%), breakage of the distal pins in two (6.5%), and severe varus malunion in two patients (6.5%). Because of the high complication rate in this series, the authors no longer use the Marchetti-Vicenzi flexible nail for treatment of femoral shaft fractures.  相似文献   
7.
Bagby  GC Jr; McCall  E; Bergstrom  KA; Burger  D 《Blood》1983,62(3):663-668
Human umbilical vein endothelial cells were cultured in supernatants of peripheral blood monocytes that had been cultured for 3 days with and without lactoferrin. Colony-stimulating activity (CSA) was measured in supernatants of the endothelial cell cultures and appropriate control cultures using normal, T-lymphocyte-depleted, phagocyte-depleted, low- density bone marrow cells in colony growth (CFU-GM) assays. Monocyte- conditioned medium contained a nondialyzable, heat labile factor that enhanced 4-15--fold the production of CSA by endothelial cells. The addition of lactoferrin to monocyte cultures reduced the activity of this monokine by 69%. Lactoferrin did not inhibit CSA production by monokine-stimulated endothelial cells. Therefore, vascular endothelial cells are potent sources of CSA, the production of CSA by these cells is regulated by a stimulatory monokine, and the production and/or release of the monokine is inhibited by lactoferrin, a neutrophil- derived putative feedback inhibitor of granulopoiesis. Inasmuch as a similar monokine is known to stimulate CSA production by fibroblasts and T lymphocytes, we suggest that mononuclear phagocytes play a pivotal role in the regulation of granulopoiesis by recruiting a variety of cell types to produce CSA.  相似文献   
8.

Objective

The purpose of this study was to eliminate orthodontic treatment in mild to moderate cases of condylar hyperplasia in its early stages by condylectomy.

Patients and methods

A total of five patients (two females and three males) aged between 17 and 40 years were treated with unilateral condylectomy of the involved side without orthodontic treatment. All patients underwent standardized clinical and radiological examination at initial consultation, before surgery, immediately after surgery, and follow-up. Objective and subjective evaluation of temporomandibular joint (TMJ) included maximal incisal opening, lateral excursions, correction of facial asymmetry, occlusal harmony, TMJ pain, and jaw function. Results were recorded at 5-year follow-up.

Results

In all our cases, we achieved good mouth opening and near to normal occlusion. Good facial aesthetics was obtained after 3 months postoperative follow-up without secondary orthodontic treatment.

Conclusion

Thus, we conclude that treatment of mild to moderate cases of unilateral condylar hyperplasia during the inactive phase can be treated with condylectomy without orthodontic treatment, and it significantly improves long-term surgical outcomes.  相似文献   
9.
10.

Aim

To compare the biomechanical properties of a newly proposed technique, utilizing intramedullary nailing and compression bolts, for the osteosynthesis of intra-articular proximal tibial fractures with meta–diaphyseal comminution, with modern and conventional plating techniques.

Methods

Fifteen left tibia 4th generation composite Sawbones models (in 3 groups of 5 for each technique) with identically reproduced type VI Schatzker tibial plateau fractures, including meta–diaphyseal dissociation, were used. Three different techniques of osteosynthesis were tested: (a) a new technique that combines intramedullary nailing and compression bolts, (b) internal fixation with a single lateral locking plate and (c) internal fixation with dual buttress plating technique. The model-device constructs were successively subjected to 500 N, 1000 N and 1500 N load levels with five cycles applied at each level on both articular compartments and a final load cycle to failure. Four parameters were recorded for each technique: the average reversible or irreversible displacement in vertical subsidence, the horizontal diastasis of the intra-articular fracture, the average passive construct stiffness and the load to failure.

Results

The new intramedullary nailing technique provided rigid intra-articular osteosynthesis being statistically similar to dual buttress plating for subsidence at medium and higher load levels. At the same time the proposed technique provided statistically equivalent stiffness values to the single lateral locking plate incarnating the rational of biologic fixation. Average load to failure was 1611 N for single lateral locking plates, 2197 N for intramedullary nailing and 4579 N for dual buttress plating. The single lateral locking plate technique had the worse results in interfragmentary displacement while dual buttress plating was superior in stiffness from the other 2 techniques. The mode of failure differed between techniques, with collapse of medial plateau occurring exclusively in the single lateral locking plates group.

Conclusion

The proposed new technique of intramedullary nailing and compression bolts demonstrates a flexural behaviour similar to single lateral locking plates, which complies with the terms and benefits of biological fixation, while at the same time maintains a rigid intra-articular stability similar to the stiff dual buttressing plating technique.  相似文献   
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