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91.
BACKGROUND: High-intensity focused ultrasound (HIFU) consists of focused ultrasound waves emitted from a transducer that are capable of inducing tissue damage. Experimental studies have shown clear damage of malignant tissue exposed to HIFU, but knowledge of in vivo effects is limited. We studied the safety and efficacy of HIFU in patients with a T1-2 N0) M0 prostate carcinoma. METHODS: HIFU treatment was performed under general anesthesia with the Ablatherm device (Technomed Medical Systems, Lyon, France), 7-12 days prior to radical prostatectomy. Only the lobe in which carcinoma was confirmed was treated. The radical prostatectomy specimen was examined histopathologically, and the changes were compared with treatment goals. RESULTS: So far, 9 patients have been treated. On histology, a sharp delineation was noted between areas treated with HIFU and untreated areas. On the dorsal border, however, incomplete destruction of tissue was noted, and in 2 cases a small residual tumor was seen in this region. In all cases complete necrosis was seen in the treated region. CONCLUSIONS: Histology reports of radical prostatectomy specimens of patients operated 7-12 days after HIFU treatment showed marked and complete necrosis in the treated area. Due to incomplete tissue destruction at the dorsal side, however, a small focus of residual vital tumor was found in 2 of 9 patients.  相似文献   
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93.
PURPOSE: SU6668 is a tyrosine kinase inhibitor which targets platelet-derived growth factor receptor-beta, fibroblast growth factor receptor-1, vascular endothelial growth factor receptor-2, and KIT. We did a phase I study to define the maximum tolerated dose and to assess the pharmacokinetics of SU6668 administered orally thrice daily with food. PATIENTS AND METHODS: Patients with histologically proven, advanced, and progressive solid tumors were included at a starting dose level of 400 mg/m2 thrice daily. The early onset of dose-limiting toxicities (DLT) required dose reductions to 100 and 200 mg/m2 thrice daily. Pharmacokinetics was done on days 1, 28, and 56. RESULTS: Sixteen patients were included. Two of the first three patients developed DLTs, which consisted of grade 4 fatigue and grade 3 serositis-like pains. Six patients at dose level 100 mg/m2 thrice daily experienced no DLT. At dose level 200 mg/m2 thrice daily, two out of seven patients experienced DLTs consisting of grade 3 abdominal pain, grade 4 anorexia and grade 3 nausea/vomiting. Increasing doses resulted in a disproportional increase in area under the curve and C(max) (peak plasma concentration). Both variables, however, decreased significantly on days 28 and 56 compared with day 1 (P < 0.05). No objective responses were observed. Acute phase response, probably mediated by interleukin-6, was observed in serial blood samples. CONCLUSIONS: The maximum tolerated dose of SU6668 given orally, thrice daily under fed conditions, is 100 mg/m2. Because of the low plasma levels reached at this dose level, the efficacy of SU6668 as a single agent is not to be expected.  相似文献   
94.
Neonates with congenital diaphragmatic hernia (CDH) suffer from a diaphragmatic defect, lung hypoplasia, and pulmonary hypertension, with poor lung function forming the major clinical challenge. Despite prenatal diagnosis and advanced postnatal treatment strategies, the mortality rate of CDH is still high. CDH has been subject of extensive research over the past decades, but its etiology remains unknown. A major problem with CDH is the failure to predict the individual response to treatment modalities like high-frequency ventilation, inhaled nitric oxide, and extracorporeal membrane oxygenation. In this study, we tested the possibility that CDH lungs are surfactant protein deficient, which could explain the respiratory failure and difficulties in treating CDH infants. We investigated this hypothesis in the nitrofen-induced CDH rat model and assessed the cellular concentrations of surfactant protein (SP)-A, -B, and -C mRNA with a quantitative radioactive in situ hybridization technique. No differences were observed between control and CDH lungs for SP mRNA expression patterns. The cellular concentration (mean OD) of SP-A and SP-B mRNA was similar at all stages whereas the mean OD of SP-C mRNA and the volume fraction of cells (% Area) expressing SP mRNA was higher in CDH lungs at term. Immunohistochemical analysis revealed no differences between control and CDH lungs for SP protein expression. No differences in the mean OD or % Area for the SP mRNAs were found between the ipsi- and contralateral side of CDH lungs. We conclude that there is no primary deficiency of surfactant proteins in the nitrofen-induced CDH rat model.  相似文献   
95.
96.
OBJECTIVE: To determine whether the alpha-catenin expression pattern and DNA content have additional value over primary tumour histology, including information on vascular invasion and tunica albuginea invasion, in detecting occult metastasis in patients with clinical stage I nonseminomatous germ cell tumours of the testis (NSGCT). PATIENTS AND METHODS: Fifty consecutive patients with clinical stage I NSGCT underwent retroperitoneal lymphadenectomy (RPLND) between 1986 and 1992. The orchidectomy specimens were histopathologically reviewed and immunohistochemically stained with mouse monoclonal anti-alpha-catenin antibody. The presence of an aberrant or negative staining in >10% of the malignant cells was defined as abnormal; in all other cases tumours were classified as normal. Furthermore, intact nuclei were isolated from 50 microm thick paraffin sections of the primary tumour, Feulgen stained, and analysed with an image-analysis system. RESULTS: Of the 50 patients, 14 had positive retroperitoneal nodes (stage IIa, 28%), one pathologically staged I patient developed a lung metastasis (stage IV) within 3 months of RPLND. Univariate analysis showed that the presence of embryonal cell carcinoma, vascular invasion and tunica albuginea invasion were predictive for occult metastases. In multivariate logistic regression analysis only vascular and tunica albuginea invasion were significant. All 11 patients with no embryonal cell carcinoma in the primary tumour were classified as having pathological stage I disease. Also, the tumours which were DNA-diploid (three) or DNA-polyploid (two) were pathologically stage I. In screening for occult metastases the DNA content and the alpha-catenin expression pattern had no additional value. CONCLUSION: Vascular and tunica albuginea invasion have prognostic value in identifying patients with clinical stage I NSGCT at high risk for occult retroperitoneal disease. In contrast, the absence of embryonal cell carcinoma could predict all patients at low risk for metastasis. The DNA-ploidy also identified patients at low risk. Other DNA-analyses and the alpha-catenin expression pattern provided no additional information. Further studies are recommended to identify patients who are at low or high risk for metastasis.  相似文献   
97.
Cytokine profiles in aqueous humour were studied in relation to corneal disease and subsequent corneal graft survival or rejection. Cytokine levels in samples obtained from eyes with clear grafts (n = 59) were all within the normal range. At the time of penetrating keratoplasty (n = 146), intraocular levels of IL-6 were increased in 38% (50/131), most markedly in eyes with previous allograft failure or herpetic stromal keratitis. The level of IL-10 was increased in 1 eye (n = 144) and of IL-4 and IFN-gamma in none. During rejection (n = 10), the levels of IL-6 in aqueous humour were increased in 75% (3/4), of IL-10 in 50% (3/6), of IL-4 in none (0/4) and of IFN-gamma in 40% (2/5). In conclusion, the levels of total protein and IL-6 were increased prior to penetrating keratoplasty in eyes with previous inflammation. These results could however not predict the final outcome of the graft. Increased intraocular levels of IL-6, IL-10 and IFN-gamma were observed during rejection.  相似文献   
98.
The application fo postembedding immunocytochemistry on serial semithin plastic sections, revealed the presence of γ-aminobutyric acid (GABA)-positive and aspartate-positive neurons in cultured neocortex explants. GABA-positive neurons were found in all layers of the cultured cortex, whereas aspartate-positive neurons were mainly restricted to layer 6. Although exact quantification was not carried out because of the variability in aspartate immunoreactivity, colocalization of GABA and aspartate immunoreactivity could unambiguously be observed in a few neurons.  相似文献   
99.
One versus two embryo transfer after IVF and ICSI: a randomized study   总被引:6,自引:0,他引:6  
BACKGROUND: The main reason for adverse treatment outcome in assisted reproduction is the high rate of multiple pregnancies. The only strategy to avoid dizygotic twins is to transfer one embryo at a time. METHODS: A total of 144 women, who had had at least four good quality embryos available after IVF/intracytoplasmic sperm injection (ICSI) and who had no more than one previous failed treatment cycle, were randomized to have either one or two embryos transferred. The treatment outcomes including those after frozen embryo transfer were compared between these groups. RESULTS: The clinical pregnancy rate per transfer was 32.4% in the one embryo transfer group and 47.1% in the two embryo transfer group, the difference being not significant. Eleven twin deliveries (n = 39) occurred in the two embryo transfer group and there was one pair of monozygotic twins in the one embryo transfer group. The cumulative pregnancy rate per patient after transfer of fresh and frozen embryos was 47.3% in the one embryo transfer group and 58.6% in the two embryo transfer group. CONCLUSIONS: Our results indicate that among women who have good quality embryos in their first IVF/ICSI, good treatment results can be achieved. They support the idea of changing embryo transfer policy towards one embryo transfer without any remarkable decrease in the success rate, while dizygotic twins can be avoided.  相似文献   
100.
Primary cultures of osteogenic precursor cells derived from rat bone marrow stroma were performed on commercially available pure titanium discs (Ti c.p.) and surface modified Ti c.p.using a sol-gel technique (Ti sol). In separate repeated experimental runs, cell behavior and in vitro mineralization were compared with cultures on silica gel bioactive glass discs (S53P4). All substrates were incubated in simulated body fluid prior to the experiment. Overall, variable effects between experimental runs were seen. Apparently, this was due to the heterogeneous nature of the used cell population. Therefore, only careful conclusions can be made. Initial cell adhesion and growth rates between 3 and 5 days of culture--analyzed by cell numbers--were in general comparable for the two titanium substrates, while initial growth up to day 3 is suggested to be higher in Ti c.p. compared to Ti sol. Although initial cell adhesion on the S53P4 glass discs was lower than the titanium substrates, cell growth rates appeared to be higher on the silica gel compared to the two titanium substrates. Further, there were some indications that the early and late osteoblast differentiation markers, alkaline phosphatase and osteocalcin, monitored up to day 24, were elevated in Ti c.p cultures compared to Ti sol cultures. There were no differences observed in in vitro mineralization between the titanium groups. S53P4 seemed to display a substantially higher differentiating capacity for both osteogenic cell markers as well as in vitro mineralization compared to the two titanium substrates.  相似文献   
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