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Our study reviewed nine patients who were treated with the VAC? Abdominal Dressing System after suffering pelvic fractures and soft tissue loss after high‐energy pelvic trauma. Between March 2008 and August 2009, our clinic treated nine patients with complicated perineal injuries from high‐energy pelvic trauma with multiple irrigation and debridement procedures and broad‐spectrum antibiotics. Protective ostomies were created for all nine patients. Required interventions were made for associated injuries, and VAC? application was started. All patients were male, with an average age of 24·3 (range 21–32) years, and a mean injury severity score of 36·4 (range 16–59). Wound diameters ranged from 15 to 30 cm, and wound depths ranged from 5 to 25 cm. The injuries included one traumatic bilateral hemipelvectomy, and three unilateral and two bilateral lower extremity amputations. Intensive care unit length of stay averaged 12 (6–19) days, and average hospital length of stay was 44·12 (31–64) days. Beginning at an average of day 17 (±5·9 days) post‐injury, wound cultures detected no bacterial colonisation. One patient died on the sixth day after injury from septic complications. Two patients' wounds were closed by primary closure, and six patients' wounds were closed by split thickness grafts after an average of 31·4 (17–50) days. Optimal treatment of high‐energy perineal injuries requires early and extensive debridement and rich irrigation. The application of the VAC? system as temporary coverage of large complex wounds in the pelvic region enhances wound healing and facilitates an early grafting process.  相似文献   
74.
Axial pattern flaps are characterized by a single vascular pedicle that supplies the whole flap and carry the danger of flap loss. For this reason, monitoring and early identification of vascular perfusion is important for flap prognosis. The most commonly used method for flap monitoring is clinical assessment, but it has certain limitations. The bioelectrical properties of tissues can be affected by ischemic conditions, and a preliminary study showed that the bioelectrical resistance of blood was decreased under thrombotic conditions. In this controlled study, the resistance values of the axial flaps were calculated during thrombosis. A total of 28 rats were randomly divided into a control group (n = 14) and an experimental group (n = 14). Axial flaps were elevated based on the inferior epigastric pedicle. For the ischemic group, microvascular clamps were placed in the ischemic group to produce artificial thrombosis from day 1 of the experiment. Bioelectrical resistance was measured every 30 minutes for the first 6 hours and then daily after that. The resistance values from the ischemic group decreased progressively, and 150 minutes after the clamping, the difference became statistically significant (P < 0.05). The results showed that the assessment of flap resistance is a valuable tool and may allow early recognition of a compromise in the vascular system before clinical signs become obvious.  相似文献   
75.
Cervical osteophytes may cause dysphagia by compressing the esophagus and may cause dysphonia by compressing the larynx and inferior laryngeal nerve. The occurrence of dysphagia and dysphonia due to cervical osteophytes has rarely been reported in literature. In this article, a case, in which the multiple cervical osteophytes were found to be the cause of dysphagia and dysphonia, was evaluated by imaging methods and electrophysiological evaluation of swallowing and the case was discussed in the light of relevant literatures.  相似文献   
76.
Diagnosis of polycystic ovary syndrome (PCOS) is very difficult in women with ovulatory cycles. We assessed the diagnostic value of prostate-specific antigen (PSA) and free prostate-specific antigen (fPSA) in women with ovulatory or anovulatory PCOS. Study group consisted of 62 women with PCOS and 35 healthy female controls. PCOS group was divided into two subgroups as anovulatory (n = 42; 68%, Group A) and ovulatory group (n = 20; 32%, Group B). A cut-off level of PSA and fPSA was established for the sensitivity, specificity, positive likelihood ratio, area under curve, diagnostic accuracy, and positive and negative predictive values of diagnosis of PCOS. In group A, a PSA level of greater than 10 pg/ml yielded a sensitivity of 73.2%, a specificity of 80%, and a diagnostic accuracy of 73%, with a positive predictive value of 88.2% and a negative predictive value of 59.3%. An fPSA level of greater than 2.1 pg/ml yielded a sensitivity of 71.2%, a specificity of 80.4%, and a diagnostic accuracy of 87%, with a positive predictive value of 87.2% and a negative predictive value of 58.4%. In group B, a PSA level of greater than 10 pg/ml yielded a sensitivity of 65%, a specificity of 80%, and a diagnostic accuracy of 73%, with a positive predictive value of 76.5% and a negative predictive value of 69.6%. An fPSA level of greater than 2.1 pg/ml yielded a sensitivity of 65.4%, a specificity of 80.4%, and a diagnostic accuracy of 87%, with a positive predictive value of 75.5% and a negative predictive value of 68.4%. Circulating androgens and hirsutism are independently associated with the degrees of PSA and fPSA in PCOS women. Increased plasma levels of PSA (>10 pg/ml) and fPSA (>2.1 pg/ml) could be helpful as a diagnostic tool for women with ovulatory or anovulatory PCOS.  相似文献   
77.
Several human diseases have been associated with the overproduction of reactive oxygen species (ROS) and subsequently various antioxidants emerged as potential therapeutic agents that scavenge ROS. As an oxidative stress model of human disease, we used hydrogen peroxide (H2O2) to study effect of ROS on C6 glioma cells as a surrogate for astrocytes. H2O2 induced dose- and time-dependent apoptotic cell death which was preceded by growth arrest, and transiently activated the signalling proteins ATF-2, ERK1/2 and AKT in C6 glioma cells. While several antioxidants failed to block H2O2-induced apoptosis of these cells, Ginkgo biloba extract (EGb) totally prevented the cell death and growth inhibition induced by H2O2. Interestingly, EGb did not prevent the activation of ATF-2, ERK1/2 and AKT induced by H2O2 excluding the role of these factors in the pro-apoptotic effect of H2O2. We have previously shown that the lipid-lowering drug, simvastatin, causes apoptotic cell death in C6 glioma cells [Koyuturk M, Ersoz M, Altiok N. Simvastatin induces proliferation inhibition and apoptosis in C6 glioma cells via c-jun N-terminal kinase. Neurosci Lett 2004;370(2-3):212-7]. However, in parallel experiments with H2O2, EGb was unable to prevent cell death induced by simvastatin suggesting the involvement of separate signalling pathways between H2O2 and simvastatin. Thus, EGb and other plant flavonoids might have potential as protective agents against apoptosis through scavenging ROS upon cerebral or myocardial diseases associated with free radical generation.  相似文献   
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79.
This study investigates angiogenesis and the expression of thrombospondin 1 in invasive ductal carcinoma of the breast and their possible relation to platelet counts and platelet activity. The study included 20 cases of invasive ductal carcinoma. Platelet activity was evaluated by determining thromboxane B2 and cyclic guanosine monophosphate (cGMP) levels by enzyme immunoassay (EIA).Thrombospondin (TSP) 1 and CD34 expression was studied immunohistochemically. Mean platelet count of the patient group was significantly greater than the mean platelet count of the control group (P < 0.05). The platelet counts were positively correlated with tumour size (r=0.609; P < 0.01). Platelet counts were higher in the patients who had grade 3 microvessel density (P < 0.05). The mean basal platelet cGMP level in the patient group was significantly lower than it was in the control group (P < 0.05). Focal TSP immunoreactivity was detectable in 5 (20%) cases in the tumour cells, and in 9 (45%) cases in the stroma. We did not find any correlation between TSP-1 staining and angiogenesis, platelet counts, platelet activity, and the histological prognostic parameters. Our study confirms the essential role of platelets in tumour growth and angiogenesis. Decreased levels of cGMP in the patient group may cause platelet hyperreactivity. Although thrombospondin 1 may be upregulated in malignant breast tissue, this is not sufficient for tumour growth and dissemination according to our results.  相似文献   
80.
Hydrogels that mimic native tissues chemically and structurally have been increasingly sought for a wide variety of tissue engineering applications. Gelatin can be naturally derived from different sources and functionalized to fabricate hydrogels that exhibit high cytocompatibility and favorable biodegradable properties. The amino groups on the gelatin backbone can be substituted by adding varying proportions of methacrylic anhydride (MAA) to create biomimetic hydrogels which can be used as tissue engineering scaffolds. Gelatin from different sources yields hydrogels with distinctive physical, chemical, and biological properties. In this work, gelatin from bovine skin was used to fabricate hydrogels with varying degrees of crosslinking content using 1, 4, 7, and 10 mL MAA. The material properties of these hydrogels were characterized. The cytocompatibility of the gelatin-based hydrogels was studied using L6 rat myoblasts. The hydrogels from bovine skin gelatin exhibit mechanical properties that are conducive for applications which require substrates to propagate cell growth, migration, and proliferation rapidly. These hydrogels exhibit exceptional tunability behavior which makes them useful and applicable to culture different cell types.

Gelatin from bovine skin was chemically modified to synthesize biocompatible photolabile hydrogels for tissue engineering applications.  相似文献   
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