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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Jeffery J Maclean Cynthia R Lee Mauro Alini James C Iatridis 《Journal of orthopaedic research》2004,22(6):1193-1200
The goal of this study was to characterize the anabolic and catabolic mRNA response of the disc to dynamic loading to determine if variations in the magnitude and/or frequency of loading could elicit different cellular responses. Sixty-eight Wistar rats were instrumented with an Ilizarov-type device spanning caudal disc 8-9. Seventy-two hours after surgery, animals were anesthetized and loaded at either 1 or 0.2 MPa at a frequency of 1, 0.2 or 0.01 Hz for 2 h (6 groups). The surgical control (Sham) animals underwent anesthesia with no loading. Loaded (c8-9) and internal-control discs (c6-7 and c10-11) were dissected and annulus and nucleus tissue were separately analyzed by real-time RT-PCR for levels of anabolic (collagen-1A1, collagen-2A1, aggrecan) and catabolic (MMP-3, MMP-13, ADAMTs-4) mRNA. In the nucleus, a frequency-dependent response was seen at 1 MPa with anabolic genes stimulated at 0.01 Hz and catabolic genes at 1 Hz. In the annulus all frequencies resulted in significant up-regulation of catabolic mRNA at 1 MPa loading. In general loading at 0.2 MPa or 0.2 Hz had little effect on gene expression. The results suggest that gene expression of the annulus appears to be more dependent on the magnitude of applied stress, while the nucleus is both magnitude- and frequency-dependent. 相似文献
92.
M De Cristofaro C Baldi M Petrone A Vecchio M Di Mauro B Ravera 《Giornale italiano di cardiologia》1985,15(10):995-997
A case of cardiac echinococcosis in a 22 year-old woman is reported. Clinical findings and cardiac catheterization data offered only presumptive evidence of an intraventricular mass but failed to make a positive diagnosis of cardiac involvement by hydatid disease. Using Two-Dimensional Echocardiography (2-DE) we were able to identify a rounded structure with multiple loculation into the right ventricle, highly suggestive of a hydatid cyst. Surgery confirmed our findings. We confirm the ability of 2-DE to detect and characterise intracardiac masses and we suggest that 2-DE could be considered the procedure of choice in the diagnosis of cardiac hydatid disease. 相似文献
93.
Krengli Marco Ferrara Eleonora Guaschino Riccardo Puta Erinda Turri Lucia Luciani Ilaria Sacchetti Gian Mauro Franco Pierfrancesco Brambilla Marco 《Annals of nuclear medicine》2022,36(5):450-459
Annals of Nuclear Medicine - [18F] fluorodeoxyglucose positron emission tomography/computed tomography ([18F] FDG-PET/CT) is used for diagnosis, staging, response assessment and prognosis... 相似文献
94.
Perugia G Ciccariello M Pirolli F Chinazzi A Teodonio S Borgoni G Croce F Liberti M 《Urology》2012,79(4):e51-e52
Paraurethral leiomyoma is a rare, benign, hormone-dependent neoplasm of mesenchymal origin affecting women. The clinical evidence varies, but it tends to be asymptomatic or associated with the sensation of a foreign body; urinary symptoms are rarely described. The distinction among urethral, paraurethral, and anterior vaginal wall leiomyoma can be very difficult owing to their anatomic proximity. Excision of the mass is the recommended treatment, and the diagnosis is confirmed by the pathologic finding to rule out the presence of a sarcoma. A case of paraurethral leiomyoma associated with dysuria, dyspareunia, and obstructive voiding symptoms is reported. 相似文献
95.
Purpose
To evaluate laparoscopic hyperthermic intraperitoneal chemotherapy (HIPEC) with neoadjuvant, adjuvant, or palliative purpose in order to discuss potential clinical implications.Methods
A systematic search of PubMed??s Medline through August 2011 using the keywords laparoscopic, hyperthermic, and chemotherapy.Results
Eight studies encompassing a total of 183 patients were considered. The indications for laparoscopic HIPEC was neoadjuvant in 5 patients, adjuvant in 102 patients, and palliative in 76 patients. There were 13 minor complications not requiring repeat operation, and no deaths related to procedure were recorded. When performed to treat refractory malignant ascites, the procedure was effective in 95?% of cases.Conclusions
Laparoscopic HIPEC appears to be a safe and effective procedure when performed to treat malignant ascites refractory to less aggressive treatments. The effectiveness of laparoscopy to perform HIPEC with neoadjuvant or adjuvant purpose needs to be confirmed by further studies. 相似文献96.
Bello L Lucini V Giussani C Carrabba G Pluderi M Scaglione F Tomei G Villani R Black PM Bikfalvi A Carroll RS 《Neurosurgery》2003,52(1):177-85; discussion 185-6
OBJECTIVE: The biological features of malignant gliomas include high cell proliferation, extensive local infiltration of tumor cells into normal brain, and marked neovascularization. alphavbeta3 integrin is highly expressed in malignant gliomas and plays a role in glioma growth. This article investigates the in vitro and in vivo effects of a synthetic alphavbeta3 integrin inhibitor called IS20I on human malignant gliomas. METHODS: The in vitro effects of IS20I were studied by performing adhesion assays, competition studies, semi-in vivo angiogenic assays, and migration and proliferation assays. For the in vivo experiments, IS20I was administered systemically in nude mouse intracranial and subcutaneous malignant glioma models. RESULTS: IS20I reacted selectively to alphavbeta3 integrin in glioma cells and tissues. In vitro, IS20I strongly inhibited angiogenesis and simultaneously exhibited potent antimitotic and antimigratory effects on numerous tumor and endothelial cell lines. In addition, at high concentrations, IS20I induced endothelial and tumor cell apoptosis. In vivo, when IS20I was administered intraperitoneally in subcutaneous and intracranial nude mouse glioma models, it potently reduced malignant glioma growth. Inhibition levels of 76 and 82% were observed at concentrations of 1 and 5 mg/kg, respectively, in the U87 intracranial model. The suppression of tumor growth is associated with a decrease in tumor vascularity, an increase in apoptosis, and a decrease in tumor cell proliferation. CONCLUSION: This work expands the understanding of the effects of anti-alphavbeta3 integrin inhibitors on malignant gliomas. In addition to direct proapoptotic and antiangiogenic effects, IS20I inhibits tumor and endothelial cell proliferation and migration, resulting in a potent inhibition of glioma growth in vivo. 相似文献
97.
Bellantone R Lombardi CP Bossola M Boscherini M De Crea C Alesina P Traini E Princi P Raffaelli M 《World journal of surgery》2002,26(12):1468-1471
Total thyroidectomy is not frequently performed in cases of benign disease because of the associated risk of postoperative hypoparathyroidism and recurrent laryngeal nerve (RLN) damage. We chose a series of patients who had undergone total thyroidectomy (TT) for benign thyroid tumors to evaluate the safety of this approach and its role in the treatment of nonmalignant lesions of the thyroid. We considered only patients with a minimum follow-up of 24 months. Records of 526 patients who underwent TT were carefully reviewed, assessing for perioperative complications and late sequelae. The mean age was 44 +/- 15.7 years; 109 patients (20.7%) were male and 417 (79.3%) were female. Altogether, 65 patients (12.3%) were operated on for toxic goiter, 429 (81.6%) for bilateral nodular goiter, and 32 (6.1%) for thyroiditis. Postoperative hemorrhage requiring reoperation occurred in 8 cases (1.5%). The incidences of permanent RLN palsy (considered as a percentage of the nerves at risk) and permanent hypocalcemia were 0.4% and 3.4%, respectively. A trend toward a decrease in the complication rate was observed during the last 5 years. There were no disease recurrences during a mean follow-up of 44 months. The results of our series show that TT can be performed safely in patients, with a low incidence of lifetime disabilities. TT has the advantage of reducing/avoiding the risk of disease recurrence and reoperation and should therefore be considered a valuable option for treating benign thyroid diseases. 相似文献
98.
Background: When investigating the degree of formation of intimal hyperplasia (IH) quantification of the extent of the lesion is crucial to its assessment and analysis. The aim of the present study was to establish a new methodology (IH index) for estimating the degree of IH associated with vascular prosthesis implantation. Methods: Ten female Merino sheep underwent a standard gelatin sealed Dacron (GSD) patch grafting procedure in the left common carotid artery. The grafts were harvested 4 weeks following implantation and processed for assessment of IH by two methodologies ? mean intimal thickness (MIT) and IH index. The advantages and disadvantages of the two methods for expressing the degree of IH were compared. Results: The IH index is less labour intensive but is as accurate as the MIT method in quantifying the IH lesion, statistical analysis showing high correlation and measurement agreement between the two methods. Conclusion: The IH index is a labour saving standardized methodology for quantification of IH in the current animal model. 相似文献
99.
Cristiano Cervellera Mauro Gaggero Danilo Macciò 《Optimal control applications & methods.》2017,38(6):1193-1207
This paper investigates the use of lattice point sets as an efficient method to sample uniformly the state space of discrete‐time dynamic systems for the solution of finite‐horizon optimal control problems using approximate dynamic programming. Lattice point sets are a kind of discretization method, commonly employed for efficient numerical integration, providing a regular and balanced sampling of the state space based on the repetition of elementary unit cells. A convergence analysis of the approximate solution of the control problem to the optimal one is provided, pointing out that such sampling schemes allow one to efficiently exploit possible regularities of the cost‐to‐go functions. Furthermore, it is shown that a higher accuracy may be obtained through suitable transformations of the state vector of the dynamic system. Another advantage of lattice point sets over other sampling schemes is the possibility of evaluating a priori the goodness of a given set over another through the explicit computation of a specific parameter. Simulation results concerning the optimal control of a water reservoirs system are presented to show the effectiveness of the proposed approach. 相似文献
100.