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1.
Of four patients with rheumatoid arthritis and Dupuytren's contracture, two were not aware of the presence of Dupuytren's contracture. When both diseases coexist, the presence of rheumatoid hand deformities, especially flexion and ulnar deviation of the metacarpophalangeal joints, may mask the flexion deformity caused by Dupuytren's contracture. Careful clinical examination should rule out the presence of a pathologic fascial cord. When reconstructive surgery is indicated for the rheumatoid hand in the presence of advanced Dupuytren's contracture, staged surgery would be appropriate and reconstruction of Dupuytren's contracture should precede other surgery.  相似文献   

2.
GnRH receptor values are 30-50% of normal in pituitaries of hpg male mice, and testicular LH receptors only 8% of normal (160.4 +/- 17.6 and 2013 +/- 208.1 fmol/testis respectively). In male hpg mice bearing fetal preoptic area (POA) hypothalamic implants for 10 days there was no change in pituitary GnRH receptors, pituitary gonadotrophin content, or seminal vesicle weight. However, testicular weights and LH receptors were doubled in 4/10 mice and 2 had increased serum FSH levels. Between 26 and 40 days after implantation pituitary GnRH receptors and pituitary LH increased to normal male levels, although at 40 days serum and pituitary FSH concentrations had reached only 50% of normal values. Testicular and seminal vesicle weights increased more than 10-fold by 40 days after implantation and LH receptors to 70% of normal. In hpg female mice bearing hypothalamic implants for 30-256 days pituitary gonadotrophin concentrations were normal, even though GnRH receptors reached only 60% of normal values (6.18 +/- 0.4 and 9.8 +/- 0.4 fmol/pituitary respectively). Serum FSH was substantially increased from values of less than 30 ng/ml in hpg mice to within the normal female range in hypothalamic implant recipients. Ovarian and uterine weights increased after hypothalamic grafting from only 4-5% to over 74% of normal values. LH receptors increased from 6.5 +/- 1.3 fmol/ovary for hpg mice to 566.9 +/- 39.2 fmol/ovary for implant recipients. Vaginal opening occurred about 23 days after implantation and these animals displayed prolonged periods of oestrus.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

3.
The aim of this article was to show the participation of epidermal growth factor (EGF) in the pathogenesis of Dupuytren's disease (palmar contracture). The concentration of EGF in specimens obtained from 68 patients with Dupuytren's contracture and 14 controls was examined immunochemically with the use of enzyme-linked immunosorbent assay. The determined EGF concentration in pathologic aponeurosis with symptoms of Dupuytren's disease (median, 6.29 ng/g; range, 1.67 to 63.09 ng/g) showed significantly different values (p = 0.036) in comparison with the control group (median, 10.1 ng/g; range, 5.13 to 39.81 ng/g). The changes in EGF concentration were shown in tested groups of pathologic tissues that were formed according to the clinical stage of disease progression. The significantly lower concentration than that seen in the control group characterizes tissues with first and third degrees of palmar contracture progression (p = 0.025 and p = 0.018, respectively). In the group of patients with second-degree disease progression, the EGF level increased transiently. Nevertheless, in comparison with the other groups, the difference was not significant. The group with the fourth degree of the disease showed EGF concentrations that resembled the control values. The authors conclude that significant differences in levels of EGF concentration between contractured and normal fasciae may suggest the participation of this cytokine in the pathogenesis of Dupuytren's disease.  相似文献   

4.
Long-term use of polyurethane breast prostheses: a 14-year experience   总被引:1,自引:0,他引:1  
I have used polyurethane prostheses for the past 14 years, implanting 220 implants into 130 patients who desired breast reconstruction after subcutaneous mastectomy or cancer ablation or simply breast augmentation. I theorize that a polyurethane-covered implant resists contracture, retaining its compressibility because the fibroblasts proliferate into the polyurethane in many different directions. When the fibrils contract, the forces of contracture counterbalance one another, resisting contracture. However, when smooth prostheses are implanted, fibrils are directed in a circular fashion around the implant and naturally contract, leading to firmer breasts. There were 115 prostheses inserted following subcutaneous mastectomy, and 22 percent developed contracted capsules. Seven implants became exposed because of skin necroses; one was removed because of a Staphylococcus infection; and two patients developed a combination of polyurethane and silicone granulomas. These developed only with the earlier implant, where there was shedding of the polyurethane sponge layer and silicone bled from the low-viscosity silicone used in the earlier implants. No granulomas were noted with the currently used Surgitek Replicon implant. Eighty-five breasts were reconstructed after cancer ablation with polyurethane implants, and the contracture rate was 2.3 percent. Other complications were minimal. A smaller group of patients had augmentation mammaplasty, and 20 prostheses were placed in 10 patients. A 15 percent contracture rate was noted in this group. In this study, 82 percent of patients were followed for up to 14 years. Capsular contractures occurred in 30 implants between 1 and 11 years, for an average recurrence at 6.3 years. The overall contracture rate was 13 percent. Other complications were minimal. All implants were placed subcutaneously or subglandularly, and all were drained.  相似文献   

5.
BackgroundA large number of clinical studies have reported that the different materials used in breast implants were a possible cause of the different incidence rates of capsular contracture observed in patients after implantation. However, this theory lacks comprehensive support from evidence-based medicine, and considerable controversy remains.ObjectivesIn this study, a cumulative systematic review examined breast augmentation that used implants with textured or smooth surfaces to analyze the effects of these two types of implants on the occurrence of postoperative capsular contracture.MethodsWe conducted a comprehensive search of literature databases, including PubMed and EMBASE, for clinical reports on the incidence of capsular contracture after the implantation of breast prostheses. We performed a cumulative meta-analysis on the incidence of capsular contracture in order from small to large sample sizes and conducted subgroup analyses according to the prosthetic material used, the implant pocket placement, the incision type and the duration of follow-up. Relative risks (RR) and 95% confidence intervals (CI) were used as the final pooled statistics.ResultsThis meta-analysis included 16 randomized controlled trials (RCTs) and two retrospective studies. The cumulative comparison of textured and smooth breast implants showed statistical significance at 2.13 (95% CI, 1.18-3.86) when the fourth study was entered into the analysis. With the inclusion of more reports, the final results indicated that smooth breast implants were more likely to be associated with capsular contracture, with statistical significance at 3.10 (95% CI, 2.23-4.33). In the subgroup analyses, the subgroups based on implant materials included the silicone implant group and the saline implant group, with significant pooled statistical levels of 4.05 (95% CI, 1.97-8.31) and 3.12 (95% CI, 2.19-4.42), respectively. According to implant pocket placement, a subglandular group and a submuscular group were included in the analyses, and only the subglandular group had a statistically significant pooled result of 3.59 (95% CI, 2.43-5.30). Four subgroups were included in the analyses according to incision type: the inframammary incision group, the periareolar incision group, the transaxillary incision group and the mastectomy incision group. Among these groups, only the pooled results of the inframammary and mastectomy incision groups were statistically significant, at 2.82 (95% CI, 1.30-6.11) and 2.30 (95% CI, 1.17-4.50), respectively. Three follow-up duration subgroups were included in the analyses: the one-year group, the two- to three-year group and the ≥five-year group. These subgroups had statistically significant results of 4.67 (95% CI, 2.35-9.28), 3.42 (95% CI, 2.26-5.16) and 2.71 (95% CI, 1.64-4.49), respectively.ConclusionIn mammaplasty, the use of textured implants reduces the incidence of postoperative capsular contracture. Differences in implant pocket placement and incision type are also likely to affect the incidence of capsular contracture; however, this conclusion awaits further study.  相似文献   

6.
At the time of immediate breast reconstruction with submuscular implants, 76 consecutive patients (89 breasts) were randomized into two groups. One received a gel-saline, double-lumen implant with 40 cc of saline added to the outer lumen, while the other received the same implant plus 40 cc of saline and 16 mg methyl prednisolone (40 mg%). Patients were followed for a minimum of 3 years. The groups, which were matched for patient age and implant size, were evaluated at 3, 12, 24, and 36 months for capsular contracture, steroid atrophy, and other complications. With completion of the double-blind study, the patients with submuscular gel-saline implants with only saline added had an overall capsular contracture rate of 38 percent at 3 months, 38 percent at 12 months, and 44 percent at 24 and 36 months. Those with methyl prednisolone had an overall capsular contracture rate of 14 percent at 3 months, and this remained unchanged through the end of the study. The rates of all other complications were comparable. Methyl prednisolone in a dose of 16 mg in 40 cc saline (concentration 40 mg%), when used in the outer lumen of a double-lumen gel-saline implant in a submuscular pocket, is both safe and efficacious in reducing the risk of capsular contracture for a minimum of 3 years in patients undergoing immediate breast reconstruction with submuscular mammary implants.  相似文献   

7.
Detection of subclinical infection in significant breast implant capsules   总被引:8,自引:0,他引:8  
The pathogenesis of fibrous capsular contracture after augmentation mammaplasty is still debated. One hypothesis implicates low-grade bacterial infections as a cause. The presence of a staphylococcal biofilm in a patient with recurrent capsular contracture was previously reported. A comparative, prospective, blinded, clinical study of implants and capsules removed from patients with or without significant capsular contracture was conducted to investigate the association of biofilm contamination, breast implants, and capsular contracture.Capsule and implant samples obtained during explantation were tested by routine microbiological culture, sensitive broth culture (after maceration and sonication), and scanning electron microscopy. Clinical parameters were correlated with microbiological findings. A total of 48 implant and/or capsule samples were obtained from 27 breasts during a 22-month period. Of the 27 breasts, 19 exhibited significant contracture (Baker grade III/IV). The mean duration of implantation was 9.2 years (range, 0.4 to 26.0 years). Routine swab cultures obtained at the time of explantation were negative for bacterial growth for all samples. The sensitive broth culture technique yielded 24 positive samples (50 percent, n = 48). An analysis of capsules demonstrated that 17 of 19 samples obtained from patients with significant contracture were positive, compared with only one of eight samples obtained from patients with minimal or no contracture (p = 0.0006). Fourteen of the 17 positive cultures from significantly contracted breasts yielded coagulase-negative staphylococci, mainly, species of the Staphylococcus epidermidis group. The presence of coagulase-negative staphylococci was also significantly associated with capsular contracture (p = 0.01). There was no significant difference in the frequency of culture positivity for saline versus silicone implants (p = 0.885). Scanning electron microscopy confirmed the presence of extensive biofilm on implants and within capsules.Biofilm, in particular, S. epidermidis biofilm, was detected for a significant proportion of patients with capsular contracture. This implicates biofilm disease in the pathogenesis of contracture, and strategies for its prevention should be explored.  相似文献   

8.
Lei L  Cheng L  Hou J  Guo S  Zhu C  Shi Y  Jiang Y  Lin J 《Experimental parasitology》2012,131(4):442-447
This work reports the prevention outcomes of a praziquantel (PZQ) implant against the infection of Schistosoma japonicum in mice. The PZQ implant produced stable plasma PZQ concentrations in a range of 100-1300 ng/mL for a period of 70 days, by releasing PZQ in subcutaneous tissues in a sustained manner. To assess the prevention effects, the mice were infected at varying times after implantation. All the mice were sacrificed at 6 weeks after infection for worm and egg recovery and counting, worm morphological examination, determination of egg-hatching rates, and analysis of hepatic histology. The infection was successfully prevented for mice with early infection times (within 2-3 weeks), as nearly no worms, paired worms, eggs, or miracidia were recovered. However, in mice with late infection times (after 3 weeks), the prevention effects were diminished due to the decreased plasma PZQ concentrations at late times. Interestingly, the implants showed robust prevention effects on repeated infection at 1 and 3 weeks. In the infection-prevented mouse livers, no granuloma formation or granulomatous inflammation was observed. The results demonstrated that by blocking the development of infecting miracidia and by deactivating the eggs, the PZQ implants encouragingly prevented the S. japonicum infection and avoided liver damage.  相似文献   

9.
Little has been published regarding the treatment of patients with long-established capsular contracture after previous submuscular or subglandular breast augmentation. This study reviews 7 years of experience in treating established capsular contracture after augmentation mammaplasty by relocating implants to the "dual-plane" or partly subpectoral position. A retrospective chart review was performed on all patients who were treated for capsular contracture using this technique between 1993 and 1999. Data collected included the date of the original augmentation, the original implant location, date of revision and type of implant used, length of follow-up, outcome, and any ensuing complications. Different surgical techniques were used, depending on whether the prior implant was located in a subglandular or submuscular plane. All patients had revisions such that their implants were relocated to a dual plane, with the superior two thirds or so of the implant located beneath the pectoralis major muscle and the inferior one third located subglandularly. Of 85 patients reviewed, 54 had their original implants in a submuscular position and 31 had their initial augmentation in a subglandular position. Of the 54 patients whose implants were initially submuscular, 23 patients (43 percent) had silicone gel implants, 15 patients (28 percent) had double-lumen implants, and the remaining 16 patients (30 percent) had saline implants. Of the 31 patients whose implants were initially subglandular, 20 patients (65 percent) had silicone gel implants, three patients (10 percent) had double-lumen implants, and the remaining eight patients (26 percent) had saline implants. Fifty-one patients (60 percent) had replacement with saline implants (37 smooth saline, 14 textured saline), whereas 34 (40 percent) had silicone gel implants (seven smooth gel, 27 textured gel). The average time from previous augmentation to revision was 9 years 9 months. The average follow-up time after conversion to the dual-plane position was 11.5 months. Only three of 85 patients required reoperation for complications, all of which involved some degree of implant malposition. Of patients converted to the dual plane, 98 percent were free of capsular contracture and were Baker class I at follow-up, whereas 2 percent were judged as Baker class II. There were no Baker level III or IV contractures at follow-up. The dual-plane method of breast augmentation has proved to be an effective technique for correcting established capsular contracture after previous augmentation mammaplasty. This technique appears to be effective when performed with either silicone or saline-filled implants.  相似文献   

10.
The fate of secondary biomaterial implants was determined by bio-optical imaging and plate counting, after antibiotic treatment of biomaterials-associated-infection (BAI) and surgical removal of an experimentally infected, primary implant. All primary implants and tissue samples from control mice showed bioluminescence and were culture-positive. In an antibiotic treated group, no bioluminescence was detected and only 20% of all primary implants and no tissue samples were culture-positive. After revision surgery, bioluminescence was detected in all control mice. All the implants and 80% of all tissue samples were culture-positive. In contrast, in the antibiotic treated group, 17% of all secondary implants and 33% of all tissue samples were culture-positive, despite antibiotic treatment. The study illustrates that due to the BAI of a primary implant, the infection risk of biomaterial implants is higher in revision surgery than in primary surgery, emphasizing the need for full clearance of the infection, as well as from surrounding tissues prior to implantation of a secondary implant.  相似文献   

11.
The paper presents data on the cultivation of human dermal fibroblasts and rabbit mesenchymal stromal cells on two types of porous titanium implants, i.e., those with irregular pores formed by pressed titanium particles and those with regular pores formed by the cohesion of one-size titanium particles inside the implant. The goal of this study was to determine what type of titanium implant porosity ensured its strongest interaction with cells. Cells were cultivated on implants for 7 days. During this period, they formed a confluent monolayer on the implant surface. Cells grown on titanium implants were monitored by scanning electron microscopy. Fibroblasts interaction with implants depended on the implant porosity structure. On implants with irregular pores cells were more spread. On implants with regular pores fibroblasts enveloped particles and were only occasionally bound with neighboring particles by small outgrowths. There was no tight interaction of particles inside the implant. In implants formed by pressed particles, cells grow not only on surface, but also in the depth of the implant. Thus, we suppose that a tighter interaction of cells with the titanium implant and, supposedly, tissues with the implant in the organism will take place in the variant when the implant structure is formed by pressed titanium particles, i.e., cellular interaction was observed inside the implant. In implants with irregular pores, cells grew both on the surface and in the depth. Thus, cells exhibited more adequate interactions with irregular pore titanium implants in vitro and hopefully the same interaction will be true in tissues after the implantation of the prosthesis into the organism.  相似文献   

12.
Dupuytren's contracture is a fibroproliferative disorder characterized by progressive deposition of mature collagen fibers. In other fibrotic diseases affecting organs such as the liver, lung, heart, and skin, matrix metalloproteinases (MMPs) and their natural inhibitors, the tissue inhibitors of metalloproteinases (TIMPs), play an important role. In this study, serum concentrations of MMP-1, MMP-2, MMP-9, TIMP-1, and TIMP-2 were determined in 22 patients (five women and 17 men; average age, 67 +/- 11 years) with Dupuytren's disease using an enzyme-linked immunosorbent assay. Tissue samples were obtained for standard histological and immunohistochemical analyses. Sera and samples of palmar fascia from 20 patients (13 women and seven men; average age, 60 +/- 15 years) who had undergone hand surgery for carpal tunnel syndrome were used as the control group. Statistical analysis was performed using the Mann-Whitney test. Patients with Dupuytren's contracture presented with a TIMP-1 concentration of 437 +/- 160 ng/ml, a significantly higher TIMP-1 concentration than that seen in the control patients, who had a concentration of 321 +/- 70 ng/ml (p < 0.05). Patients with a proliferative active disease (n = 14) had a significantly higher TIMP-1 concentration (525 +/- 136 ng/ml) than patients (n = 8) with a contracture in the late involutional and residual phase (286 +/- 41 ng/ml; p < 0.05). There were no significant differences in the TIMP-2, MMP-1, MMP-2, and MMP-9 serum concentrations between patients with palmar fibromatosis and the control group. Patients with Dupuytren's disease had a significantly lower MMP-to-TIMP ratio (1.1 +/- 0.3; p < 0.05) than the control group (1.5 +/- 0.35). Patients with an active palmar fibromatosis presented a significantly (p < 0.05) reduced ratio (1 +/- 0.2) compared with those in later phases (1.4 +/- 0.3). TIMP-1 and TIMP-2 could be detected in tissue of patients with Dupuytren's contracture, with an accumulation in proliferative areas. MMPs could be detected locally in Dupuytren's tissue in a few patients, with less positive staining than for TIMPs. In the control group, there was just little or no staining for TIMPs and MMPs. The data indicate that the physiological balance between MMPs and their natural inhibitors is disturbed in patients with a proliferative active Dupuytren's disease. The decrease in the systemic MMP-to-TIMP ratio can cause increased synthesis and deposition of collagen, leading to palmar fibromatosis.  相似文献   

13.
Capsular contracture results in dissatisfaction and deformity among the 2 million women who have had silicone implants. The literature describes contracture rates as high as 74 percent. I present a comparison of rates and incidences of contracture in patients augmented with smooth and textured double-lumen silicone implants. A total of 165 "smooth" and 63 "textured" implant patients were included in this study, which spans 12 years, 1978-1990. All patients underwent bilateral aesthetic augmentation performed by the same surgeon. Of the 165 smooth implant patients, 74 (44.8 percent) experienced contractures requiring treatment. Of the 63 textured implant patients, 3 (4.8 percent) previous contracture patients experienced sudden fibrosis within 3 months. All others remained soft. It appears that deeply textured silicone surfaces delay or decrease the rate and incidence of clinical capsular contracture, at least for 2 years.  相似文献   

14.
目的:探讨新型基因药物rAAV-shRNA-CDK2对人肝癌裸鼠血液系统的影响,评估其安全性。方法:采用皮下接种人肝癌Hep G2细胞构建荷瘤裸鼠,10天后将其随机分为3组:肿瘤组、NC组及rAAV-shRNA-CDK2组,每组雌雄裸鼠各6只。通过尾静脉注射定量给药,15天后取眼球血并处死裸鼠。检测血常规指标和骨髓细胞周期。结果:所有裸鼠平均血小板体积略高于该周龄鼠的正常值范围,但各组间比较差异无统计学意义(P0.05);肿瘤组雌性裸鼠的中性粒细胞百分比显著高于rAAV-shRNA-CDK2组,而淋巴细胞百分比明显低于rAAV-shRNA-CDK2组(P0.05),但指标数值均在正常值范围内。各组雄性裸鼠骨髓细胞周期分布比较差异均无统计学意义(P0.05),而肿瘤组雌性裸鼠骨髓细胞G2/M期比例明显高于rAAV-shRNA-CDK2(P0.05),但两组其他周期骨髓细胞比例比较差异无统计学意义(P0.05)。结论:rAAV--shRNA-CDK2并未对人肝癌裸鼠血液系统产生不良影响。  相似文献   

15.
MISTI Gold breast implants (Bioplasty, St. Paul, Minn.) filled with polyvinylpyrrolidone-hydrogel were developed as a promising alternative to silicone-filled implants. Some studies have reported on the positive effects of the implant, such as improved radiolucency and biocompatibility of the gel; however, there are also reports that such implants increased in volume and were subject to capsular contracture in the human body, resulting in demands for their removal. The purpose of this retrospective study was to analyze the long-term results of a series of patients with MISTI Gold breast implants. Between 1991 and 1993, the authors inserted 83 MISTI Gold implants in 61 patients with an average age of 46 years (range, 16 to 69). The authors were able to follow up 48 patients with 71 MISTI Gold implants. The average follow-up was 68 months (range, 10 to 108 months). The retrospective study found that 59 percent of all MISTI Gold implants were removed after an average period of 4.14 years. The main reason for implant removal was an increase in volume of 38 percent, followed by capsular contracture in 14 percent of all 71 MISTI Gold implants. The average increase in volume of all removed MISTI Gold implants was 43 percent. Capsular contracture was graded as Baker I and II in 63 percent and as Baker III and IV in 37 percent. In conclusion, the authors believe that MISTI Gold implants do not fulfill the criteria of safe breast implants, and they agree with the December of 2000 opinion of the Medical Devices Agency of the Department of Health in London that the hydrogel-filled breast implants should not be used until more information about the filler material and its metabolic fate is available.  相似文献   

16.
Although textured silicone breast implants have been shown to reduce the incidence of capsular contracture, there is little evidence if this effect is maintained in the long term. It has been 10 years since the double-blind randomized trial in which 53 patients received either Mentor smooth (26) or textured silicone gel implants (27). Of the 14 patients who were not known to have developed a contracture in the smooth group, 11 were reviewed. Three had bilateral contractures. In the textured group, 18 of the 24 patients not known to have contractures were reviewed. None had developed contractures. At 10 years, the incidence of capsular contracture was 65 percent of patients with smooth implants (an increase of 6 percent on the 3-year results) and 11 percent for the textured implant patients (no change on the 3-year results). A database containing the details of 1100 patients reinforces these results by examining the differences in contracture rates of textured, smooth, and polyurethane-coated implants. The effect of submuscular placement on reducing contracture rates regardless of texturing is discussed, as is the apparent increase in capsular contracture in patients who smoke.  相似文献   

17.
The implant-tissue response to the silicone gel mammary prosthesis requires a more thorough evaluation in light of recent concerns related to human connective-tissue diseases, contracture, infection, and neoplasia. The silicone prosthesis is not a homogeneous implant but is a milieu of various silicone chemistries. Silicone polymer precursors and prosthesis components (silicone shells, shells extracted of their low-molecular-weight components, silica-free silicone, silicone oil, fumed silica, and silicone extract) were implanted subcutaneously using a nonhemorrhagic technique into the backs of Lew/SsN rats (n = 90), two implants per rat, for periods of 7, 14, 28, 56, and 90 days for a total of 6 implants per material per time period. Histologic analysis was performed on specimens from the harvested soft tissue. The intensity of the cellular and capsular response was lowest for the silicone oil and increased as the material's molecular weight increased and material compliance decreased. Fumed silica elicited the most highly reactive cellular response. From this study it is apparent that the polymer's molecular weight influences its migration, encapsulation, and intensity of cellular response. Further, the silicone extract distillate elicited a highly intense cellular response with pronounced lymphocyte invasion. The human relevance of this work awaits further correlation with implant retrieval and in vivo performance.  相似文献   

18.
Tao Q  Li D  Zhang L  Luo S 《PloS one》2012,7(6):e39936
The purpose of this paper is to report the noninvasive imaging of hepatic tumors without contrast agents. Both normal tissues and tumor tissues can be detected, and tumor tissues in different stages can be classified quantitatively. We implanted BEL-7402 human hepatocellular carcinoma cells into the livers of nude mice and then imaged the livers using X-ray in-line phase-contrast imaging (ILPCI). The projection images' texture feature based on gray level co-occurrence matrix (GLCM) and dual-tree complex wavelet transforms (DTCWT) were extracted to discriminate normal tissues and tumor tissues. Different stages of hepatic tumors were classified using support vector machines (SVM). Images of livers from nude mice sacrificed 6 days after inoculation with cancer cells show diffuse distribution of the tumor tissue, but images of livers from nude mice sacrificed 9, 12, or 15 days after inoculation with cancer cells show necrotic lumps in the tumor tissue. The results of the principal component analysis (PCA) of the texture features based on GLCM of normal regions were positive, but those of tumor regions were negative. The results of PCA of the texture features based on DTCWT of normal regions were greater than those of tumor regions. The values of the texture features in low-frequency coefficient images increased monotonically with the growth of the tumors. Different stages of liver tumors can be classified using SVM, and the accuracy is 83.33%. Noninvasive and micron-scale imaging can be achieved by X-ray ILPCI. We can observe hepatic tumors and small vessels from the phase-contrast images. This new imaging approach for hepatic cancer is effective and has potential use in the early detection and classification of hepatic tumors.  相似文献   

19.
Spear SL  Elmaraghy M  Hess C 《Plastic and reconstructive surgery》2000,105(4):1542-52; discussion 1553-4
The earliest silicone breast implants were smooth-surface, silicone rubber devices filled with either silicone gel or saline. Because of persistent problems with capsular contracture, polyurethane-covered silicone implants were developed as an alternative. Particularly in the short run, these alternatives proved highly successful at reducing the incidence of capsular contracture. By 1990, polyurethane-covered implants were rapidly becoming the preferred implant choice of many plastic surgeons, but for legal, regulatory, financial, and safety reasons they were withdrawn from the market by Bristol-Myers in 1991. Meanwhile, during the late 1980s, surface texturing and improved materials became available on other silicone breast implants and expanders. Most studies suggest that textured-surface silicone gel-filled implants, saline-filled implants, and tissue expanders have less frequent capsular contracture than their smooth-surface counterparts.  相似文献   

20.
LJH-OS人骨肉瘤裸鼠原位移植模型的建立及其生物学特性   总被引:2,自引:0,他引:2  
用人成骨肉瘤细胞系LJH- OS的传代移植瘤组织作为移植材料,进行胫骨原位移植及皮下移植。结果发现胫骨原位移植的潜伏期较短,生长快。皮下移植瘤呈局限性膨胀性生长,有不完整的纤维包膜,未见肺转移,观察7 周无明显消瘦;而胫骨原位移植瘤浸润基层,无纤维包膜,且发生肺转移,7 周时有明显消瘦。原位移植的裸鼠血清ALP水平高于皮下移植者。说明裸鼠胫骨微环境较皮下组织更适于人骨肉瘤的浸润及转移表达,裸鼠胫骨原位移植模型的恶性生物学行为更接近临床骨肉瘤患者的实际情况,该原位移植模型的建立为骨肉瘤的研究提供了良好的实验模型。  相似文献   

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