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61.
Nutritive Quality of Fermented Sorghum   总被引:1,自引:0,他引:1  
The relative nutritive value (% RNV) of sorghum fermented at 25°C and at 35°C increased significantly (P < 0.05) over the % RNV of the control. During the consecutive 7-day fermentation at 25°C, time had no effect on the % RNV. The highest % RNV (56.45%) was achieved at the end of 1 day. Fermentation at 35°C was influenced by the time, with the highest % RNV (61.11%) obtained at the end of 7 days. Available lysine and methionine increased substantially (P < 0.01) over the control when sorghum was fermented at 25°C or 35°C for 4 days. Sorghum fermented at 25°C and at 35°C had methionine contents of 25.68 and 26.79 mg/g N, respectively, whereas the control contained only 11.25 mg/g N. Lysine levels were 33.2 and 34.5 mg/g N in sorghum fermented at 25°C and at 35°C, respectively, whereas the control contained 9.1 mg/g N. None of the available B-vitamins studied was altered significantly in the fermented samples.  相似文献   
62.
An experimental animal model was used to investigate the effect of bioactive glass (BG) granules and nonresorbable polytetrafluoroethylene (PTFE) membrane on the repair of cortical bone defects adjacent to titanium and BG implants. Thirty-two Astra® (diameter 3.5 mm) dental implants were inserted bicortically and 42 conical BG implants (diameter 2.5–3.0 mm) monocortically, into fitted holes of rabbit tibia. Before implantation, a standardized bone defect was created by drilling an extra hole (diameter 3.0 mm) adjacent to each implant site. Twenty-eight defects were filled with BG granules (diameter 630–800 m) (BG group) and 28 defects were left empty but covered with PTFE membrane (PTFE group). No material was used in 18 control defects (control group). Morphometrical evaluation with a digital image analysis system was used to measure bone repair as percentages of the defect area on scanning electron microscopy (SEM) and light microscopy pictures. Bone–implant contact was measured as percentages of the thickness of the cortical bone. At 6 and 12 wk, bone repair in defects in connection with titanium implants was 23.2% and 36.6% in the BG group, 23.2% and 32.4% in the PTFE group, and 47.2% and 46.2% in control defects. Corresponding figures for BG implants were 33.2% and 40.1% in the BG group, 16.6% and 33.5% in the PTFE group, and 25.7% and 54.9% in control defects, BG granules and new bone together filled 82.7% and 68.5% of the defect area adjacent to titanium implants, and 75.9% and 74.4% of the defect adjacent to BG implants at 6 and 12 wk, respectively. Better bone–implant contact was achieved at the defect side with BG than titanium implants (77.0% versus 45.0% at 12 wk). The results indicate that BG granules are useful in treatment of bone defects adjacent to dental implants. BG coating of the implant seems to improve osseointegration in the defect area.  相似文献   
63.
为制备具有亲水和防污自清洁性能的PVC建筑薄膜,在经低温等离子体改性的PVC薄膜表面涂覆SiO2作为隔离层,然后采用旋涂法将TiO2涂覆于薄膜表面,制备得到PVC/SiO2/TiO2复合膜。利用XRD、FTIR、SEM、EDS等测试手段对复合膜的形貌和结构进行表征,并用接触角测试仪测定了其亲水性能,经紫外光照后,复合膜的接触角由42.2°降为10.9°,结果表明TiO2层的涂覆大大地提高了PVC薄膜的亲水性能。  相似文献   
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Aromatase inhibitors have been available for a number of years and their ability to reduce circulating estradiol levels has been shown to produce clinical benefit in women with advanced breast cancer. Until recently, the only commercially available aromatase inhibitor was aminoglutethimide. Although aminoglutethimide has been shown to be efficacious in the treatment of advanced breast cancer, it does cause significant toxicity and requires the use of concomitant hydrocortisone therapy. Anastrozole is one of a new class of potent aromatase inhibitors able to suppress estradiol to the limit of detection of sensitive assays without suppressing adrenal steroidal synthesis. Two large clinical trials (n = 764) conducted in the U.S.A. and in Europe evaluated two doses of anastrozole, 1 and 10 mg a day, compared to megesterol acetate, 40 mg four times a day, in postmenopausal women who had progressed while on tamoxifen. Response rates and time to progression with anastrozole were similar to those of megesterol acetate. Objective responses (CR + PR) were 10.3%, 8.9% and 7.9% in the 1 and 10 mg of anastrozole and megesterol acetate treatment groups, respectively. Another 25.2%, 22.6% and 26.1% had stable disease for over 24 weeks on 1, 10 mg anastrozole and megesterol acetate, respectively. Anastrozole and megesterol acetate were well tolerated; however, more patients had significant weight gain on megesterol acetate than with anastrozole treatment. The weight gain seen with megesterol acetate continued to increase over time. Anastrozole has a better therapeutic index (fewer side-effects) and has recently been approved by the FDA and a number of other regulatory agencies around the world for the treatment of advanced breast cancer.  相似文献   
66.
We present and analyze a model for the interaction of human immunodeficiency virus type 1 (HIV-1) with target cells that includes a time delay between initial infection and the formation of productively infected cells. Assuming that the variation among cells with respect to this 'intracellular' delay can be approximated by a gamma distribution, a high flexible distribution that can mimic a variety of biologically plausible delays, we provide analytical solutions for the expected decline in plasma virus concentration after the initiation of antiretroviral therapy with one or more protease inhibitors. We then use the model to investigate whether the parameters that characterize viral dynamics can be identified from biological data. Using non-linear least-squares regression to fit the model to simulated data in which the delays conform to a gamma distribution, we show that good estimates for free viral clearance rates, infected cell death rates, and parameters characterizing the gamma distribution can be obtained. For simulated data sets in which the delays were generated using other biologically plausible distributions, reasonably good estimates for viral clearance rates, infected cell death rates, and mean delay times can be obtained using the gamma-delay model. For simulated data sets that include added simulated noise, viral clearance rate estimates are not as reliable. If the mean intracellular delay is known, however, we show that reasonable estimates for the viral clearance rate can be obtained by taking the harmonic mean of viral clearance rate estimates from a group of patients. These results demonstrate that it is possible to incorporate distributed intracellular delays into existing models for HIV dynamics and to use these refined models to estimate the half-life of free virus from data on the decline in HIV-1 RNA following treatment.  相似文献   
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68.
Nine 1,2,5-trisubstituted benzimidazole derivatives were prepared and their structure have been elucidated by IR, NMR spectral data and elemental analyses. Analgesic activity of the compounds prepared was investigated in mice by modified KOSTER test. Anti-inflammatory activity of these compounds was investigated by a carregeenan-induced hind paw edema model in mice. Their antibacterial activities were examined against S. aureus, E. faecalis, E. coli, P. aeruginosa, and antifungal activity against three kinds of yeast-like fungi (C. albicans, C. parapsilosis, C. stellatoidea).  相似文献   
69.
The condition of multiple breast duct papillomas although relatively common in adult women is not a well recognized clinical entity in adolescent females. The risk of adolescents with this condition developing carcinoma is presently unknown, although in adulthood it is regarded by some authorities as a precancerous condition. We report a case of a 14-year-old girl with such a lesion who remains well with no breast abnormalities 2 years after surgery. The clinicopathological features of the condition and the relevant literature are discussed.  相似文献   
70.
BACKGROUND: Controversy exists as to the treatment regimen necessary to best provide optimal local control for inflammatory breast carcinoma (IBC). This study was conducted to determine if mastectomy combined with radiotherapy offered any advantages over radiotherapy alone in patients with IBC who had been treated with doxorubicin-based combination chemotherapy. METHODS: A retrospective review of 178 women treated for IBC on doxorubicin-based multimodality therapy protocols between January 1974 and September 1993 was performed. Clinical and histologic response to treatment, time to local recurrence, survival, and ultimate control of local disease were analyzed. Kaplan-Meier analysis was used to examine survival and relapse times, and Fisher's exact test was used to test differences in treatment outcomes. Significance was determined at p < or = 0.05. RESULTS: Median follow-up was 89 months (range 22 to 223 months). Locoregional disease persisted in seven patients and recurred in 44 patients who had been rendered disease free at a median time of 10 months. The mortality rate after a local recurrence (LR) was 98%, and all patients but one with LR developed systemic metastases. Response to induction chemotherapy influenced the incidence of LR, and the amount of residual disease found on histologic examination of mastectomy specimens was highly prognostic for local failure. Patients who underwent mastectomy in addition to radiotherapy had a lower incidence of LR than did patients who received radiotherapy alone (16.3% vs. 35.7%, p = 0.015). CONCLUSIONS: The addition of mastectomy to combination chemotherapy plus radiotherapy improved local control in patients with IBC. The addition of mastectomy to chemotherapy plus radiotherapy improved distant disease-free and overall survival in patients with a clinical complete or partial response to induction chemotherapy. Patients who had no significant response to induction chemotherapy received no survival or local disease-control benefit from the addition of mastectomy to their treatment regimen. These patients should be considered for entry into clinical trials of new treatment regimens.  相似文献   
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