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排序方式: 共有392条查询结果,搜索用时 640 毫秒
1.
Microvascular reconstruction of a cranial defect in a 10-week-old infant, which is the youngest case in the literature, is reported. A latissimus dorsi free muscle flap was transferred to cover the defect and a split thickness skin graft was placed over the muscle flap. Despite the successful flap transfer in this case, microvascular reconstruction in an infant has its own risks and infants should be discussed as a separate entity apart from the other pediatric patients.  相似文献   
2.
BackgroundHeterotopic ossification (HO) is common after total joint arthroplasty and usually does not cause diagnostic problems. However, the occurrence of HO after oncologic prostheses implantation can be troublesome as it may mimic a locally recurrent tumor. Because this distinction could have a profound impact on the surgeon and patient, it is important to distinguish the two entities; to our knowledge, no study has evaluated this after oncologic endoprosthetic reconstruction around the knee after tumor resection.Questions/purposes(1) How common is the occurrence of HO compared with local recurrence (LR) after resection of bone sarcoma and the use of an oncologic knee prosthesis? (2) Are there any factors associated with the development of HO after limb salvage procedures with an endoprosthesis? (3) What features allow the surgeon to differentiate HO from a locally recurrent tumor in this setting?Methods‏Between 2002 and 2018, we performed 409 resections of primary bone tumors followed by reconstructions with oncologic endoprostheses. Of these, 17% (71 of 409) died before 2 years and did not have HO at that time, 2% (8 of 409) were lost to follow-up before 2 years, and another 2% (10 of 409) did not have radiographs available at a minimum of 2 years after surgery (and had not developed HO before then), and so could not be analyzed, leaving 320 patients for analysis in this retrospective study. Forty-two patients were excluded; 2% (5 of 320) for a history of failed allograft reconstruction, 3% (8 of 320) for pathologic fracture at presentation, 2% (6 of 320) for inadequate or complicated biopsy, 1% (2 of 320) for stem fractures, 2% (7 of 320) for stem loosening, and 4% (14 of 320) for extracortical bone bridging, leaving 278 patients for final evaluation. Two observers analyzed AP and lateral radiographs for signs of HO at a mean follow-up of 63 ± 33 months after surgery. We defined HO as extraskeletal bone formation in soft tissues. The primary study endpoint was survivorship free from HO, as ascertained by a competing-risks estimator. To identify factors associated with HO appearance, the demographic, radiographic, clinical, pathologic, and surgical characteristics were compared between patients with HO and those who had no lesion. Characteristic features were also compared between patients with HO and those with LR to help their differentiation. Univariate analysis was used for all statistical evaluations.ResultsHO developed in 8% (21 of 278) of patients in whom oncologic knee prosthesis was implanted. LR developed in 10% (28 of 278) of the patients. According to survivorship estimates, the HO-free survival rate was not different from the LR-free survival rate at 2 years after oncologic knee reconstruction (76 ± 5% [95% CI 63 to 87] versus 74 ± 5% [95% CI 62 to 88]; p = 0.19). History of infection was more common in patients with HO than in patients with no lesion (19% [4 of 21] versus 5% [12 of 229], Odds ratio [OR] 6 [95% CI 2 to 17]; p < 0.001). The male sex was more common in the HO group as well (76% [16 of 21] versus 55% [128 of 229], OR 2 [95% CI 1 to 5]; p = 0.03). The Modular Universal Tumor and Revision System prosthesis was more frequently used in patients with HO (67% [14 of 21]) compared to those with no lesions (40% [92 of 229]; OR 2 [95% CI 1 to 5]; p = 0.02).‏ The lesion border in radiographs was ill-defined in 19% (4 of 21) of patients with HO and 100% (28 of 28) of patients with LR (OR 8 [95% CI 3 to 20]; p < 0.001). The median time to the appearance of HO was shorter than the time to LR (8 months [3 to 13] versus 16 months [11 to 21], [95% CI 10 to 13]; p < 0.001). Pain at presentation was more frequent in patients with LR than in those with HO (86% [24 of 28] versus 14% [3 of 21], OR 36 [95% CI 7 to 181]; p < 0.001).ConclusionHO may occur after the use of oncologic knee prostheses for reconstruction after tumor resection. In most patients, HO could be differentiated from local recurrence through identifying a well-defined border on radiographs. Otherwise, factors such as an earlier time of presentation and absence of pain could suggest an HO, rather than an LR.Level of EvidenceLevel III, therapeutic study.  相似文献   
3.
The effects of hyperbaric oxygen (HBO) and heparin on the survival of the rat inferior epigastric venous flap were investigated. Preliminary transcutaneous oxygen measurements showed that partial oxygen pressure values of venous flaps increased at 2.5 ATA pressure while inhaling 100% oxygen. During the experiment, 128 venous flaps of two different sizes and 50 composite grafts were prepared bilaterally in 89 rats. Perivenous areolar tissue was removed from the pedicle vein in all flaps. Half of the venous flaps were isolated from the wound bed. Initial flap perfusion was tested by fluorescein injection during flap elevation. Four treatment groups were created: control, heparin, HBO, and HBO+heparin. After 6 days of treatment, the mean surviving flap area was calculated for each group. Surviving flaps were reelevated, final flap perfusion was tested by fluorescein injection, and flaps were harvested for histological examination. The mean survival rates of the HBO (26.56%) and the HBO+heparin (36.87%) groups were significantly higher than the control (0%) and the heparin (0%) groups (p<0.01). None of the composite grafts survived. Smaller flaps and nonisolated flaps survived better, although not significantly (p>0.05). Veins were enlarged both clinically and histologically. Fluorescein uptake was delayed during initial flap elevation but was normal during reelevation. These findings imply that the rat inferior epigastric venous flap may be an ischemic flap with capillary circulation through a single venous pedicle, but it needs HBO treatment to survive, especially during the acute period. Heparin treatment, reducing the flap size, and presence of a vascular wound bed also improve survival rates.  相似文献   
4.
A neurocutaneous island flap model: an experimental study in rats   总被引:5,自引:0,他引:5  
Neurocutaneous flaps have been popularized recently in clinical reconstructive surgery. However, controversies exist concerning their anatomy and physiology. The particular role of neural vasculature in the survival of these skin flaps is also quite undefined in the experimental setting, and additional studies on this subject are necessary. The goal of this study was to describe a neurocutaneous flap in a rat model and to investigate its blood supply. Thirty male Sprague-Dawley rats weighing 300 to 350 g were used in this study, which was conducted in two stages. During the first stage, the lower extremities of 10 rats were dissected for the anatomic study of the neurocutaneous flap. A constant cutaneous nerve innervating the anterolateral thigh skin was exposed. It arose either from the saphenous nerve or the superficial epigastric nerve and was accompanied by a constant longitudinal arterial plexus. The tiny neural vessels were conveyed by the superficial fascia along their course. A 30 x 30-mm cutaneous island flap, which was based only on the cutaneous nerve with its accompanying vessels and a strip of superficial fascia, was raised on the anterolateral thigh skin using an operating microscope. The well-perfused skin territory was marked after sodium fluorescein injection. The stained skin territory was located centrally and medially on the whole island flap, and it was approximately 10 x 20 mm. This finding was confirmed by the qualitative assessment of the vascularity for this skin territory in microangiography. After studying the pedicle anatomy and determining the optimal viable skin island, the second stage of the study was performed. The remaining 20 rats were divided into two groups. In the experimental group (N = 10), a neurocutaneous island flap (10 x 20 mm) was outlined on the anterolateral aspect of the thigh at its middle third. It was designed in such a way that its short and long axes lay in the center of the distance between the anterior superior iliac spine and the anterior aspect of the knee joint. After identification and dissection of the neurovascular pedicle, the flap was raised in a lateral-to-medial direction without including the deep fascia. At this point the flap remained connected only by the pedicle and a strip of superficial fascia surrounding it. It was sutured in the same place. In the control group (N = 10), the pedicle of the flap was severed and the skin island was sutured back as a composite graft. All the experimental flaps survived well. In the control group, none of the flaps survived except one that was partially viable. The flaps in the experimental group were reelevated as neurocutaneous island flaps on day 7 for microangiographic study, and specimens were processed for histologic staining. Microangiography revealed the extent of neural vasculature and vascularization of the skin through cutaneous perforators. Histologic investigation demonstrated the neural vessels that were related closely to the superficial fascia. The authors propose a neurocutaneous island flap model in the lower extremity of the rat in which the survival of the flap depended mainly on the neural arterial supply. It was also demonstrated that the superficial fascia played a role as a connective tissue framework for conveying tiny neural blood vessels to reach the skin. This model may serve as a reproducible and reliable neurocutaneous island flap model for additional studies in this field.  相似文献   
5.
AimsThe rising prevalence of metabolic syndrome has made it a major health concern. Chronic occupational exposure to organic solvents affects different systems of the body. This study aimed to investigate the association between exposure to organic solvents and the prevalence of metabolic syndrome in petroleum refinery workers.MethodThis study was conducted in 2019–2020 on workers employed in an Iranian petroleum refinery. The demographic and occupational information on the participants was obtained using the interview method. Their height, weight, and blood pressure were measured by the occupational health team, and fasting blood samples were taken from them to measure the paraclinical parameters.ResultsIn this study, 1009 petroleum refinery workers were analyzed. The prevalence of metabolic syndrome in workers was 20.1% and it was about two times higher in exposed workers (CI 95%: 1.61–3.35) compared to non-exposed ones. Factors associated with the prevalence of metabolic syndrome include age, higher BMI, exercise, and longer exposure to organic solvents.ConclusionFindings of this study suggested that exposure to organic solvents is associated with increased prevalence of metabolic syndrome (the highest association was observed with elevated serum triglycerides). Besides, longer exposure to organic solvents increased the risk of developing metabolic syndrome.  相似文献   
6.
7.
Increase of distribution of environmental contaminants such as heavy metals have been caused the knowledge of the safety and hygiene of food is very important, especially eggs, because of its role in the daily diet. There are very few studies about the investigation of the heavy metal contents in egg-white. In this study, six heavy metals include Aluminium (Al), Arsenic (As), Lead (Pb), Cadmium (Cd), Mercury (Hg), Antimony (Sb) in egg-white from 32 industrial poultry farms were investigated, by ICP-OES. All the samples were collected in all area of Markazi Province, Iran in autumn 2013. The mean concentrations of heavy metals in egg-white as follows: 0.119 for Al, 0.785 for As, 0.750 for Pb, 0.249 for Cd, 0.270 for Hg and 0.186?mg/kg for Sb. Also, the concentration of the some heavy metals were higher than maximum allowable concentration that probably it is associated to use pesticides and activities of industrial factories around the poultry farms.  相似文献   
8.
9.
Lawsone (2-hydroxynaphthalene-1,4-dione) is a natural product which shows significant biological activity. Aminomethylnaphthoquinone Mannich bases derived from lawsone constitute an interesting class of naphthoquinones and/or their metal complexes have demonstrated a series of important biological properties. So, this review aimed to document the publications concerning the synthesis of aminomethylnaphthoquinone Mannich bases from lowsone, aldehydes and amines and their metal complexes using different conditions, and investigation of their applications.

Lawsone (2-hydroxynaphthalene-1,4-dione) is a natural product which shows significant biological activity.  相似文献   
10.
Impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) are two risk groups for type 2 diabetes. Type 2 diabetes is characterized by both impaired insulin secretion and insulin resistance but their relative contribution to the development of hyperglycemia may differ due to heterogeneity of the disease. Combined glucose intolerance (CGI), on the other hand, seems to represent a more advanced stage of prediabetes that bears a distinctly higher risk of progression to diabetes and its comorbidities. This study has the aim to compare isolated IFG and CGI categories with respect to the degree of early phase insulin secretion abnormalities and insulin resistance. Subjects who had IFG (fasting glucose: 110-126 mg/dl) were included in the study. A 75-g oral glucose tolerance test (OGTT) with insulin response was done and subjects were classified according to the WHO criteria. Six subjects were excluded because they had diabetic glucose tolerance. A total of 66 patients (53.4 +/- 11.1 years, female/male: 48/18) were divided into two groups according to their glucose tolerance in OGGT (Group 1: isolated IFG and group 2: CGI). Early phase insulin secretion was measured by intravenous glucose tolerance test (IVGTT) and OGTT. Insulin resistance was assessed by the R value of the homeostasis model assessment (HOMA). We did not find any statistically significant difference between groups according to age, gender, body mass index (BMI), fasting glucose, fasting insulin, insulin-AUC (0-180 min) and HOMA-R values. In OGGT there was no statistically significant difference between 0', 30', 60' and 90' insulin levels of the groups; only 120' and 180' insulin levels were higher in CGI than in IFG group (p<0.05). In IVGTT, there was no statistically significant difference between glucose levels of the groups. Furthermore, insulin response to intravenous glucose was higher in IFG than in CGI (p<0.05). Our data demonstrate that isolated IFG and CGI are similar with respect to the degree of insulin resistance, and that subjects with CGI had a more prominent deficit in early phases of insulin secretion.  相似文献   
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