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1.
AIM: The aim of the study was to analyse the number of soft-tissue complications after internal fixation of calcaneal fractures and to evaluate risk factors leading to these complications. MATERIAL: A retrospective analysis of 126 consecutive patients with 148 operatively treated calcaneal fractures was performed. Only primarily closed fractures were included in the study. RESULTS: Wound healing was problematic in 35 cases (24 per cent). The wound was infected in 23 cases (16 per cent) and a wound edge necrosis was observed in 12 cases (8 per cent). The soft tissue complication needed operative treatment in 20 cases (14 per cent). The complications did not lead to amputations in any case. In the end of the follow up all wounds had healed. CONCLUSIONS: The statistical analysis identified a longer delay in surgery and longer operation time to be positive risk factors for wound complications.  相似文献   
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To assess whether initial surgery is beneficial for patients with primary dislocation of the patella, we carried out a prospective randomized study. Knee stability was examined under anesthesia, and associated injuries were excluded by diagnostic arthroscopy. 55 patients then had closed treatment and 70 patients were operated on with individually adjusted proximal realignment procedures.

Surgery gave no benefit based on 2 years of follow-up. The subjective result was better in the non-operative group in respect of mean Houghston VAS knee score (closed 90, operative 87), but similar in terms of the patient's own overall opinion and mean Lysholm II knee score. Recurrent instability episodes (redislocation or recurrent subluxation) occurred in 20 nonoperated and in 18 operated patients. Of these, 15 and 12, respectively, then suffered redislo-cations. Function was better after closed treatment. Serious complications occurred after surgery in 4 patients.

In conclusion, the recurrence of patellar dislocation may be more frequent than reported, whatever the form of treatment. Routine operative management cannot be recommended for primary dislocation of the patella.  相似文献   
4.
Between November 1984 and January 1994 in our department, a total of 2500 patients were treated with totally absorbable internal fixation devices. We studied these patients and analyzed results with regard to the volume of the absorbable implants and the development of wound infection. Of the 2500 patients 2044 were trauma patients and 456 were operated on for orthopedic disease. In 1466 patients treated with implants made of self-reinforced polyglycolic acid (SR-PGA) only, the patients who developed wound infection had a higher implant volume (P=0.07) than those who did not; this difference was close to statistical significance. In the 446 patients who received only implants made of self-reinforced poly-l-lactic acid (SR-PLLA), the 5 who developed wound infection had a mean implant volume more than three times that of the non-infected patients (P=0.01). We found that in the patients treated with the earlier SR-PGA implants, which contained a green staining material, there was no correlation between implant volume and incidence of wound infections. On the other hand, both the non-stained SR-PGA implants, which have been in clinical use since 1989, and the SR-PLLA implants, seem to be more predictable in terms of wound infections. We believe that this difference, is largely due to the lower level of tissue reactions with these newer implants.  相似文献   
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In massive burns, early excision and a free flap reconstruction is, in some cases, limb saving. From October 1979 to August 1993, eleven patients with massive burn injury in the upper extremity were treated using a free flap reconstruction. Eight cases were acute or subacute and three were late reconstructions. The following free flaps were used: rectus femoris microneurovascular musculocutaneous flap (2), latissimus dorsi flap (4), rectus abdominis flap (3), gluteal thigh flap (1), lateral arm flap (1), and serratus flap (1). The gluteal thigh flap was lost and it was later replaced by a rectus abdominis flap. In three cases successful reanastomosis was performed. Functional late reconstructions were performed in nine patients. In all eleven patients the limb was saved and functional recovery was satisfactory. We recommend that a free musculocutaneous or muscle flap is used, proximal to the wrist, if after careful excision of nonviable tissue, tendons, bone joint or major vessels are exposed. The rectus femoris musculocutaneous flap is a useful solution to restore extensor musculature of the forearm after extensive injury.  相似文献   
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A new type of swab (Cellswab; Cellomeda, Turku, Finland), utilizing a highly absorbent cellulose viscose sponge material, was compared to some traditional swabs. The survival of 14 aerobic and 10 anaerobic and microaerophilic bacterial species in the Cellswab, two commercial swab transport systems (Copan, Brescia, Italy, and Orion Diagnostica, Espoo, Finland), and one Dacron swab (Technical Service Consultants Ltd. [TSC], Heywood, United Kingdom) was evaluated. Bacteria were suspended in broth, into which the swabs were dipped. The Cellswab absorbed 1.3 times more fluid and released 3.5 times more fluid upon plating than the other swabs. Aerobic bacteria were stored in dry tubes, the others in transport medium, at 4 degrees C and room temperature (RT), for up to 14 days. Swab samples were transferred to plates at 0, 1, 2, 4, 7, and 14 days. For 10 strains the Cellswab yielded > or =10% of the original CFU for longer than all the other swabs. In the clinical study, the ability of the Cellswab to detect beta-hemolytic streptococci from throat samples (n = 995) was compared to that of the TSC Dacron swab. The swabs performed equally, both when their samples were transferred to plates immediately and after storage for 1 day at 4 degrees C or RT. The changes in normal microbiota after storage were also similar. The Cellswab was found to perform at least as well as ordinary swabs. It was better at storing fastidious strains, and at keeping bacteria viable for long storage times; it might well be a useful replacement or complement to ordinary swabs.  相似文献   
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BACKGROUND/AIMS: Merkel cell carcinoma (MCC) is a rare malignant cutaneous neuroendocrine tumour that mostly affects the elderly. It shows rapid progression of the primary tumour, together with a vertical growth pattern into the underlying subcutaneous tissue. Metastatic dissemination to regional lymph nodes is early and frequent. Tenascin-C (Tn-C) is a large extracellular matrix glycoprotein that is expressed in various benign and malignant processes. Expression of Tn-C is also associated with invasion and cellular proliferation, and is often downregulated in fully evolved advanced carcinomas. In previous studies, Tn-C expression correlated with prognosis in tumours of different origin. METHODS: Immunohistochemistry was used to investigate the expression of Tn-C in 25 MCC specimens and to evaluate the prognostic importance of this glycoprotein. RESULTS: Seventeen samples expressed Tn-C. Staining was mainly seen in the invasion borders and within the connective tissue septae inside the tumours. The expression of Tn-C correlated significantly with large tumour size. There was also frequent expression of Tn-C in primary tumours with metastatic dissemination. Most of the Tn-C negative samples were of small size. CONCLUSIONS: Tn-C expression seems to increase with tumour size and malignant behaviour. Expression was slightly enhanced in tumours with high proliferative indices. Expression is seen mainly in areas of invasive growth and, in this respect, resembles that of other invasive tumours.  相似文献   
8.
Summary In order to understand more fully the effect on pulmonary function of whole body exposure to cold during submaximal exercise, we measured pulmonary function indices in ten healthy male students and ten healthy male forestry workers of similar age following submaximal treadmill walking at different temperatures in a climatic chamber. After measuring the maximal aerobic capacity with a cycle ergometer test, the subjects had to walk on four separate occasions in the climatic chamber at an intensity of 70%–75% of their individual maximal heart rate; the first at normal room temperature and then randomly, either at 0°C or at −20°C, and vice versa. The duration of each walk was 8 min. Finally, each subject had to walk in the chamber at −20° C for 17 min. Flow volume spirometry was performed at room temperature 1, 5, 10, and 20 min after exercise and the values were compared to baseline values taken prior to the last walking test. There were only minor changes in pulmonary function indices following exercise at different temperatures. Only one student showed a reduction of over 15% in peak expiratory flow rate after an 8-min walk at −20° C. It seems that submaximal exercise of short duration, even at a temperature as low as −20° C, does not impair pulmonary function in healthy young men.  相似文献   
9.
Polymorphonuclear neutrophils (PMN) are among the first inflammatory cells to arrive at an implant interface, where they encounter with the foreign material and may produce reactive oxygen species (ROS). During the interaction between titanium and ROS, titanium-peroxy (Ti-peroxy) compounds may be formed. We used a Ti-peroxy gel, made from titanium and hydrogen peroxide, to study the effects of Ti-peroxy compounds on PMN. In the absence of serum, the Ti-peroxy gel decreased the oxidative response of PMN to yeast and PMA and reduced PMN apoptosis without inducing necrosis. These effects could not be ascribed to the release of hydrogen peroxide from the Ti-peroxy gel, because a steady-state hydrogen peroxide producing system failed to mimic the effects of the gel. The effects were similarly unaffected when PMN were preincubated with beta(2)-integrin antibodies, questioning the involvement of adhesion molecules. Nevertheless, when a filter was used to separate the Ti-peroxy gel from the cells, the gel effect on PMN life span was abolished, pointing to a contact-dependent mechanism. In the presence of serum, the Ti-peroxy gel had no effect on the PMN oxidative response and life span, but appeared rather inert. In summary, this study demonstrates that the Ti-peroxy gel has potentially anti-inflammatory properties through a combined peroxide and physical contact effect, supporting the notion that interactions between titanium and inflammatory cells are responsible for the good performance of titanium in vivo.  相似文献   
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