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51.
52.
Eight new oleanane saponins (1- 8) together with four know saponins (9-12) were isolated from the aerial parts of Meryta denhamii. Their structures were elucidated by 1D and 2D NMR experiments including 1D TOCSY, DQF-COSY, ROESY, HSQC, and HMBC spectroscopy, as well as ESIMS analysis. The antiproliferative activity of all compounds was evaluated using three murine and human cancer cell lines: J774.A1, HEK-293, and WEHI-164.  相似文献   
53.
Vitrification, an ultra-rapid cooling technique, offers a new perspective in attempts to develop an optimal cryopreservation procedure for human oocytes and embryos. To further evaluate this method for human oocytes, 796 mature oocytes (metaphase II) were collected from 120 volunteers. Since Italian legislation allows the fertilization of a maximum of only three oocytes per woman, there were 463 supernumerary oocytes; instead of being discarded, they were vitrified. When, in subsequent cycles, these oocytes were utilized, 328 out of 330 (99.4%) oocytes survived the warming procedure. The fertilization rate, pregnancy rate and implantation rate per embryo were 92.9, 32.5 and 13.2% respectively. Thus, as already reported in the literature, the vitrification procedure seems to be highly effective, safe (since healthy babies have been born) and easy to apply. In situations where embryo cryopreservation is not permitted (as in Italy), there is now good indication for routine application of the method, once further standardization is achieved.  相似文献   
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Functional near infrared spectroscopy (fNIRS) is a valuable tool for assessing oxy- and deoxyhemoglobin concentration changes (Δ[HbO] and Δ[HbR], respectively) in the human brain. To this end, photon pathlengths in tissue are needed to convert from light attenuation to Δ[HbO] and Δ[HbR]. Current techniques describe the human head as a homogeneous medium, in which case these pathlengths are easily computed. However, the head is more appropriately described as a layered medium; hence, the partial pathlengths in each layer are required. The current way to do this is by means of Monte Carlo (MC) simulations, which are time-consuming and computationally expensive. In this work, we introduce an approach to theoretically calculate these partial pathlengths, which are computed several times faster than MC simulations. Comparison of our approach with MC simulations show very good agreement. Results also suggest that these analytical expressions give much more specific information about light absorption in each layer than in the homogeneous case.  相似文献   
56.
BACKGROUND: New-onset diabetes mellitus after transplantation (NODAT) is a severe complication of kidney transplantation (KTx) with negative effects upon patient and graft survival. Several risk factors for NODAT have been described; however, the search for an early predictive marker is ongoing. It has recently been demonstrated that high concentrations of adiponectin (APN), which is an adipocyte-derived peptide with antiinflammatory and insulin-sensitizing properties, protect against future development of type 2 diabetes in healthy individuals. The purpose of this report was to study pretransplant insulin resistance and analyze pretransplant serum leptin and APN levels as independent risk factors for the development of NODAT. METHODS: A total of 68 KTx patients were studied [mean age, 48 +/- 11 years; 70% males; body mass index (BMI), 25 +/- 3 kg/m]; 31 KTx patients with NODAT and 37 KTx patients without NODAT (non-NODAT) with similar age, sex, BMI, immunosuppression, and posttransplant time were studied. All patients received prednisone and calcineurin inhibitors (75% tacrolimus and 25% cyclosporine A), and 76% of patients received mycophenolate mofetil. Family history of diabetes mellitus was recorded. Pretransplant homeostasis model assessment for insulin resistance (HOMA-IR) index was calculated from fasting plasma glucose and insulin. Pretransplant serum leptin and APN levels were determined by radioimmunoassay. RESULTS: NODAT patients showed higher pretransplant plasma insulin concentrations [NODAT, 13.4 (11-22.7) microIU/mL; non-NODAT, 10.05 (7.45-18.4) microIU/mL; P=0.049], HOMA-IR index [NODAT, 4.18 (2.49-5.75); non-NODAT, 2.63 (1.52-4.68); P=0.043], and lower pretransplant serum APN concentration [NODAT, 8.78 (7.2-11.38) microg/mL; non-NODAT, 11.4 (8.56-15.27) microg/mL, P=0.012]. Inverse correlations between APN and BMI (r=-0.33; P=0.014) and APN and HOMA-IR index (r=-0.39; P=0.002) and between APN and NODAT (r=-0.31; P=0.011) were observed. Multiple logistic regression analysis showed the patients with lower pretransplant APN concentrations to be those at greater risk of developing NODAT [Odds Ratio=0.832 (0.71-0.96); P=0.01]. CONCLUSION: Pretransplant serum APN concentration is an independent predictive factor for NODAT development in kidney-transplanted patients.  相似文献   
57.
Surgical treatment of pancreatic cancer is to date the only modality that offers a chance of long-term survival. Potentially curative surgery is an option for only about 15% of patients with pancreatic adenocarcinoma. The aim of this study was to determine the survival and to assess the association of clinical, pathological, and treatment features with survival of patients who underwent resection of pancreatic cancer at the Department of Surgery of Udine University Hospital. From November 1989 to December 2005, 137 consecutive patients, who underwent surgical procedures for pancreatic cancer, were followed in our department. We performed 76 pancreatico-duodenectomy, 26 distal pancreatectomies and 35 total pancreatectomies. The surgical reconstruction after pancreatico-duodenectomy was as follows: 11 closures of the main duct with manual nonabsorbable stitches, 24 closures of the main duct with a linear stapler, 17 occlusions of the main duct with neoprene glue and 24 duct-to-mucosa anastomoses. Mean survival time was 27.7 +/- 26.93 months (mean +/- SD) and mean disease-free survival time was 25.4 +/- 23.06 months (mean +/- SD). 1, 3, 5, 7 and 9-year survival rates were 63.9, 33.7, 21.17, 12.7 and 10.2%, respectively. Significant differences in survival were recorded by the Log-rank test for age > 70 (p = 0.001), surgical procedures (p = 0.00046) and presence of metastases (p = 0.0055) The treatment of pancreatic cancer is undertaken with two different aims. The first is radical surgery for patients with early-stage disease, mainly stage I and partly stage II. In all other cases, the aim of treatment is the palliation of the several distressing symptoms related to this cancer. The standard treatment option for resectable tumours is radical pancreatic resection according to the Whipple procedure or total pancreatectomy.  相似文献   
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59.

Aim  

To assess the predictive value of baseline ventricular dyssynchrony and myocardial contractile reserve (mCR) in identifying responders to cardiac resynchronization therapy (CRT).  相似文献   
60.
Piedmont is a region in northwestern Italy counting 4.2 million inhabitants. The purpose of our study was to update data on incidence and outcomes of hip fractures (HF) in our region to present days. The data of all patients affected by HF in 2003 in Piedmont (total: 5,386 patients) were analyzed, determining the incidence of HF, mean age, sex, fracture pattern and treatment adopted. Additionally, 564 patients underwent a questionnaire on comorbidities, complications, functional outcome and survivorship. Overall incidence of HF was 126.13/100,000 inhabitants-year. Mean hospitalization was 13.67 days. Mean time to surgery was 2.67 days. Survivorship was 94% at 3-month, 71.32% at 1-year and 60.21% at 3-year follow-up. These up-to-date data on HF in our region are in accordance with the international literature and could prove useful for Orthopaedic and Trauma surgeons for giving information to patients and their relatives.  相似文献   
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