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1.
Hamstring injuries are common, especially among athletes. A complete rupture of the proximal hamstring muscles requires surgical intervention. In this report we describe a reconstruction method for a complete proximal hamstring rupture using fascia lata autograft augmentation in addition to suture anchors. This method can be advocated in cases in which the primary repair has failed or in chronic injuries where a large defect between the distally retracted tendons and the ischial tuberosity prevents anatomic reinsertion. In our technique, a muscle-tendon flap is first created from the retracted tendon stump, turned proximally, and fixed to the ischial tuberosity by suture anchors. The fascia lata graft is then fixed from the midpart to the ischial tuberosity via the same sutures. The other sleeve of the graft is folded on the ventral side of the ruptured tendon stump and fixed by use of absorbable sutures. Then the other sleeve is folded on the dorsal side and fixed in the same manner. Finally, the fixation can still be reinforced with additional absorbable sutures passing through both sleeves of the graft, as well as the muscle-tendon bridge and the tendon stump.  相似文献   
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From 1971 to 1985, 369 athletes presented to us with stress fractures. Of these patients, 10% (37) were treated for development of delayed unions or nonunions. Twenty-seven of the patients were male and 10 were female. Their mean age was 23.1 years (range, 17 to 39). About half of the athletes were involved in endurance sports. The diagnostic criteria for a delayed union or nonunion were clinical and radiological evidence. There was a diagnostic delay of about 3.5 months in the series. Plain radiographs, tomography, and isotope scans were used in the diagnosis. Special radiographic views were also used. In 15 cases (10 hallux sesamoid bone fractures, 1 midtibial shaft fracture, 1 metatarsal V base fracture, 1 tarsal navicular fracture, 1 olecranon fracture, and 1 proximal tibial shaft fracture) nonoperative treatment was used. Operative treatment was used 22 times (5 sesamoid fractures, 5 midtibial fractures, 5 metatarsal V base fractures, 3 tarsal navicular fractures, 3 olecranon fractures, and 1 proximal tibial shaft fracture). Results were good or excellent in 32 cases (86.5%), moderate in 4 cases, and poor in 1 case.  相似文献   
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We studied the origin of transferrin receptor (CD71) positive cells in blood from seven women pregnant with a male fetus in order to explore if fetal cells could be detected among them. We used a technique that allows direct chromosomal analysis by in situ hybridization on immunologically and morphologically classified cells. Enrichment was performed by magnetic activated cell sorting (miniMACS)® using an anti-CD71 monoclonal antibody. The cells were immunophenotyped by alkaline phosphatase anti-alkaline phosphatase immunostaining with the same antibody. The origin of the immunophenotyped cells was studied by in situ hybridization using an X cosmid Y repeat chromosome specific probe cocktail. CD71 positive cells were found in six of the seven women at the range of 4 to 43 in respective samples. Over 90% of the CD71 positive cells were nucleated erythrocytes. None of the detected positive cells were shown to be fetal. Thus, the use of transferrin receptor antigen alone in combination with the miniMACS® may not be sufficient for enrichment of fetal cells.  相似文献   
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Olfactory neuroblastoma is an unusual neuroectodermal malignancy, which is thought to arise at the olfactory membrane of the sinonasal tract. Due to its rarity, little is understood regarding its molecular and cytogenetic abnormalities. The aim of the current study is to identify specific DNA copy number changes in olfactory neuroblastoma. Thirteen dissected tissue samples were analyzed using array comparative genomic hybridization. Our results show that gene copy number profiles of olfactory neuroblastoma samples are complex. The most frequent changes included gains at 7q11.22-q21.11, 9p13.3, 13q, 20p/q, and Xp/q, and losses at 2q31.1, 2q33.3, 2q37.1, 6q16.3, 6q21.33, 6q22.1, 22q11.23, 22q12.1, and Xp/q. Gains were more frequent than losses, and high-stage tumors showed more alterations than low-stage olfactory neuroblastoma. Frequent changes in high-stage tumors were gains at 13q14.2-q14.3, 13q31.1, and 20q11.21-q11.23, and loss of Xp21.1 (in 66% of cases). Gains at 5q35, 13q, and 20q, and losses at 2q31.1, 2q33.3, and 6q16-q22, were present in 50% of cases. The identified regions of gene copy number change have been implicated in a variety of tumors, especially carcinomas. In addition, our results indicate that gains in 20q and 13q may be important in the progression of this cancer, and that these regions possibly harbor genes with functional relevance in olfactory neuroblastoma.  相似文献   
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Several chromosomal regions are recurrently amplified or deleted in lung tumors, but little is known about the underlying genes, which could be important mediators in tumor formation or progression. In lung cancer, the RB1-CCND1-CDKN2A pathway, involved in the G1-S transition, is damaged in nearly all tumors. In the present study, we localized a novel amplicon in lung tumors to a fragment of less than 0.5 Mb at 12q13.3-q14.1 by using comparative genomic hybridization (CGH) on cDNA microarrays. This approach enabled us to identify 10-15 genes with the most consistent amplifications. Semiquantitative RT-PCR analyses of 13 genes in this region showed that four of them (CDK4, CYP27B1, METTL1, and TSFM) were also highly up-regulated. Immunohistochemical (IHC) analysis of 141 tumor samples on a tissue microarray showed that CDK4 was expressed at a high level in 23% of lung tumors. Six (21.4%) of the tumors with high CDK4 expression (n = 28) were shown by fluorescence in situ hybridization (FISH) to contain the 12q13.3-q14.1 amplification. For CDK4, a positive correlation was found between gene copy number (FISH and CGH array), mRNA expression (RT-PCR), and level of protein expression (IHC). CDK4 expression did not correlate with CDKN2A methylation status. Amplification of CDK4 has been described in other tumor types, but its role in lung cancer remains to be elucidated. Although CDK4 amplification seems to be a relatively rare event (4.3%) in lung tumors, it indicates the significance of the RB1-CCND1 pathway in lung tumorigenesis.  相似文献   
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We present a series of 19 avulsions of the distal tendon of the biceps brachii muscle after a follow-up of 2 to 11 years. Ten patients with delayed diagnosis and treatment (3 weeks to 5 months) were compared with nine patients treated early (within 8 days after injury). Excellent or good results at follow-up were obtained in 9 of 10 patients in the delayed-treatment group and in all 9 patients in the early-treatment group. Nine of 10 patients in the delayed-treatment group and all patients in the early-treatment group had been able to return to their preinjury levels of activity. For reference, a meta-analysis of 147 cases reported previously was performed. Ninety percent of the patients treated with an anatomic reinsertion had excellent or good results after an average follow-up of 3 years, while similar results after 3 years were seen in 60% of the patients who had nonanatomic tendon reinsertion and in 14% of the patients who were treated nonoperatively. The delay of up to 3 years between injury and anatomic reinsertion had not compromised the result. From these data we concluded that anatomic reinsertion of the avulsed distal biceps tendon to the radius is the preferred treatment in acute as well as chronic injuries.  相似文献   
10.
Avulsion fractures in athletes.   总被引:1,自引:1,他引:0       下载免费PDF全文
34 cases of avulsion fractures are described. Each fracture took place during athletic training or competition. Excepting six sportsmen participating in a general fitness programme, every patient was an active competitive athlete. There were six women and 28 men; their average age was 20.1 years, raised by a few middle-aged "fitness sportsmen". Most avulsion fractures took place in sprinters and hurdlers; next were middle and long distance renner, footballers, fitness joggers, skiers and ice-hockey players. The most usual location of a fracture was the anterior pelvic spines; avulsion fractures were also detected in various parts of lower limbs. There were fewer avulsion fractures in the area of the trunk and upper extremities. Roetgenologically, the diagnosis of an avulsion fracture is generally easy to make. However, the diagnosis is facilitated by knowing the mechanism of the injury, the technique of the athletic event, and some of the training methods. Generally, a fracture heals well, even if it requires both sufficient immobilisation and some delay in resuming physical exertion.  相似文献   
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