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971.
The severely of skin loss and the options of resurfacing is determined by taking into account the following factors. 1) The size & location of the defect, 2) The depth of the defect and the quality of the tissue bed, 3) The extent of exposed vital structures, 4) The associated bone and other tissues injuries, 5) The availability of donor skin flap. The size of the defect is the most important factor in choosing a resurfacing option. The size can be categorized into small, medium and large. A small defect is one that is less than 5 cm2 in size, a medium defect is between 5 to 15 cm2, and a large defect is greater than 15 cm2. Local flaps are usually sufficient to cover small defects <5 cm2. These are advancement flaps or rotation and transposition flaps. Regional flaps are indicated to resurface these medium‐sized defects 5 to 15 cm2. The donor is within the same region of the hand, from one of the digits or from dorsum and palmar surfaces of the hand. It is usually based on vascular or NV pedicles. Large defects >15 cm2 will need larger flaps for coverage. These large flaps are pedicled distant flaps and free flaps. In these severe injuries, there is usually associated bone and soft tissues injuries. These injuries can be reconstructed as a single stage combined reconstruction or multi‐staged reconstructions. The resurfacing should always be given priority.  相似文献   
972.
973.
Mesenchymal stem cells (MSC), easily culture-expanded from bone marrow, can significantly enhance bone defect healing. Several proteins, such as the bone morphogenetic proteins (BMPs) and in particular BMP-7, are involved in bone formation in vitro and in vivo. In this preclinical study, we evaluated if the association of human MSC (hMSC) with BMP-7 had synergic action on bone healing. Rat femoral defects (n=12) were treated with: autoclaved bone and mononucleated cells (MNC) as control group G1; bone and hMSC, group G2; bone with BMP-7, group G3; bone and hMSC plus BMP-7, group G4. Defect regeneration was evaluated with plain radiographs after 2, 4, 8 and 12 weeks and with histological analysis. We observed organized trabeculae bridging between the osteotomic ends of the host bone in rats treated with the association of hMSC and rhBMP-7. These trabeculae, formed by a core of devitalized tissue surrounded by osteoblasts, osteocytes and osteoclasts, were continuous with a cortical-like structure of bony tissue. Such new bone formation of the group treated with the association of hMSC and rhBMP-7 (G4) was clearly superior compared to rats treated with rhBMP-7 (G2) or hMSC (G3) alone, as shown by radiographic analysis and histological study. The present study suggests that the association of hMSC and BMP-7 is more effective than hMSC or BMP-7 alone in the healing of femoral defects in rats. Further studies with larger samples are required to confirm these results and to evaluate the best dosage.  相似文献   
974.
AIM: This prospective, split mouth control study was planned to clinically evaluate shown short-term caries protection of glass ionomer cement on tooth enamel placed in contact to it, as a result of fluoride release. STUDY DESIGN: The sample consisted of 83 children, aged 4-7 years, visiting a private practice during the years 1999 and 2000. All subjects met the following criteria: a Class II restoration was needed to a maxillary or mandibular primary molar on both sides of the mouth, the adjacent molars being radiographically diagnosed as sound or with caries in the relative proximal enamel only. METHODS: A resin modified glass ionomer restoration (Vitremer, 3M) was placed at the test side chosen by chance, while an amalgam or composite restoration was placed at the control side. Lesion initiation or progression adjacent to each restoration was categorized in 5 stages radiographically. STATISTICS: The non-parametric Marginal Homogeneity test for paired observations was used. RESULTS: Differences between test and control were not statistically significant (p>0.1). Two years after restorations were placed bitewings were taken from 36 children (41 pairs of restorations). Uncontrolled brushing with fluoride dentifrice was reported. Mean fluoride treatments performed were 2.2, initial visit included. Lesion progression was: 14 pairs--no progression in either side; 9 pairs--equal progression by 1 stage in both sides; 9 pairs--progression by 1 stage at test side, no progression at control side; 6 pairs--progression by 1 stage at control side, no progression at test side; 3 pairs--various other combinations of scores. CONCLUSIONS: Under these clinical conditions, fluoride release from Class II Vitremer restorations did not affect the rate of caries progression at the adjacent enamel of proximal primary teeth.  相似文献   
975.
HYPOTHESIS: Based on recent findings on the association between vascular risk factors and hippocampal atrophy, we hypothesized that hypertension and diabetes mellitus (DM) are associated with medial temporal lobe atrophy (MTA) in subjects without disability, independent of the severity of white matter hyperintensities. METHODS: In the Leukoaraiosis And DISability in the elderly (LADIS) study, we investigated the relationships between DM, hypertension, blood pressure and MTA in 582 subjects, stratified by white matter hyperintensity severity, using multinomial logistic regression. MTA was visually scored for the left and right medial temporal lobe (score 0-4), and meaned. RESULTS: Mean age was 73.5 years (sd 5.1), 54% was female. Of the subjects, 15% had DM, and 70% had a history of hypertension. The likelihood of having MTA score 3 was significantly higher in subjects with DM (OR 2.9; 95% CI: 1.1-7.8) compared with an MTA score of 0 (no atrophy). The odds ratio for MTA score 2 was not significantly increased (OR 1.8; CI: 0.9-4). Systolic and diastolic blood pressure and a history of hypertension were not associated with MTA. There was no interaction between DM and hypertension. Stratification on white matter hyperintensities (WMH) did not alter the associations. CONCLUSION: Our study strengthens the observation that MTA is associated with DM, independently of the amount of small vessel disease as reflected by WMH.  相似文献   
976.
There is growing evidence that obesity in women lead to a more severe form of hyperandrogenism and other endocrine abnormalities which may have some health implications later in life. Obese females are at higher risk for metabolic syndrome due to severe hyperandrogenemia. Calculated values for free testosterone are equivalent to those obtained by equilibrium dialysis, which is one of the reference measurement procedures (RMP) for estimation of free testosterone and may be capable of replacing values estimated using RMP's. For adult women correlations of body mass index (BMI) with calculated free (cFT) and bioavailable testosterone (cBT) are still rare, while these data are reported for peripubertal and adolescent girls. In this study we aimed to investigate the association between BMI and different androgen parameters (including calculated free and bioavailable testosterone, free androgen index, and sex hormone-binding globulin [SHBG]) in adult women with Hirsutism and with PCOS. In hirsute women with BMI > or = 25 kg/m2 measured total testosterone (TT) was significantly higher, SHBG was significantly lower and the calculated androgen parameter (FAI, cFT and cBT) were significantly higher compared to women with BMI < 25 kg/m2. In PCOS women with BMI > or = 25 kg/m2 TT was significantly higher, SHBG was significantly lower and the calculated androgen parameter (FAI, cFT and cBT) were also significantly higher compared to women with BMI < 25 kg/m2. In both the Hirsutism and PCOS-group there was a positive correlation between BMI and TT, cFT, and cBT, while BMI was negatively correlated with SHBG. In summary, in adult women with Hirsutism and PCOS obesity is associated with increased levels of TT and decreased levels of SHBG resulting in significant elevated calculated free and bioavailable testosterone levels. Obesity might lead to a more severe form of hyperandrogenism with elevated calculated free and bioavailable testosterone in the study population.  相似文献   
977.
Degranulating mast cells are increased in the airway smooth muscle (ASM) of asthmatics, where they may influence ASM function. The aim of the present study was to determine whether histamine and tryptase modulate ASM cell granulocyte-macrophage colony-stimulating factor (GM-CSF) and RANTES (regulated on activation, normal T-cell expressed and secreted) release and also to examine which receptors are involved in this release. Confluent, quiescent ASM cells from asthmatic and nonasthmatic donors were treated with histamine (1 microM-100 microM) with and without histamine receptor antagonist pre-treatment, or the protease-activated receptor (PAR)-2 agonists tryptase (0.5-5 nM) and SLIGKV (100 and 400 microM). The cells were then stimulated with interleukin (IL)-1beta and/or tumour necrosis factor (TNF)-alpha (10 ng.mL(-1)) or left unstimulated for 24 h. Release of GM-CSF and RANTES was determined by ELISA and prostaglandin (PG)E(2) measured by enzyme immunoassay. Neither histamine nor tryptase induced ASM GM-CSF or RANTES secretion. However, histamine increased IL-1beta-induced GM-CSF release and markedly reduced TNF-alpha-induced RANTES release by both asthmatic and nonasthmatic cells to a similar extent, but did not modulate PGE(2) release. All changes involved activation of the histamine H1 receptor as they were partially or fully blocked by chlorpheniramine, but not ranitidine. Tryptase, via its proteolytic activity, also potentiated GM-CSF, but not RANTES, release from asthmatic and nonasthmatic ASM cells induced by both cytokines. PAR-2 involvement in the tryptase potentiation was unlikely because SLIGKV had no effect. In conclusion, mast cells, through histamine and tryptase, may locally modulate airway smooth muscle-induced inflammation in asthma.  相似文献   
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979.
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