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21.
RY Lin AE Rappoport LM Deppisch NS Natividad W Katz 《Canadian Metallurgical Quarterly》1977,118(6):1066-1067
The third documented case of primary squamous cell carcinoma of the urachus in the English literature is reported. The interesting coincidental occurrence of the dermoid cyst of the right ovary and a complete longitudinal septum of the vagina and uterine cervix is described. 相似文献
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Studies were conducted on harvesting of Bacillus thuringiensis (Bt)-based biopesticides from fermented broths of starch industry wastewater (SIW), wastewater sludge (raw and hydrolyzed-NH and TH, respectively) and semi-synthetic soyameal to enhance entomotoxicity (Tx) by centrifugation. Pertinent factors influencing Tx, solids concentration, pH, temperature and centrifugal force were investigated. The centrifugate solids concentration beyond 100 g/l did not enhance Tx, instead caused pellet formation. Centrifugation efficiency (Tx recovery) was higher at pH 4, and temperature 20 degrees C for starch wastewater (98%), wastewater sludge (98% and 97.8% for non-hydrolyzed and hydrolyzed, respectively) and soya broth (83%). For maximum Tx recovery (SIW-95%; NH-90%; TH-98% and soya-78%), the centrifugal force and time required was 48,000 g and 30 min, respectively. Losses in recovery efficiency were lower for SIW and wastewater sludge in comparison to soya on adopting commercially recommended centrifugal force of 9000 g. The settling velocity computations for different fermented broths enabled calculation of Sigma factor for continuous commercial centrifuge of a given capacity and hence simulation of power requirements. It was established that power requirements for a given Tx recovery efficiency were highest for conventional medium (soya) in comparison to other waste-based fermented broths. 相似文献
23.
In this study, the application of response surface model in predicting and optimizing the ferro-sonication pre-treatment for degradation of bisphenol A (BPA), an endocrine disrupter compound from wastewater sludge (WWS) was investigated. The ferro-sonication pre-treatment process was carried out according to central composite design (CCD) with four independent variables such as wastewater sludge solids concentration, pH, ultrasonication time and FeSO(4) concentration. The effect of ferro-sonication pre-treatment was assessed in terms of increase in sludge solids (suspended solids (SS) and volatile solids (VS)) and organic matter (chemical oxygen demand (COD) and soluble organic carbon (SOC)) solubilization and simultaneous BPA degradation from WWS. It was observed that among all the variables studied, ultrasonication time had more significantly affected the efficiency of the ferro-sonication pre-treatment process followed by FeSO(4) and solids concentration. Through this optimization process, it was found that maximum BPA degradation of 88% could be obtained with 163 min ultrasonication time, 2.71 mg/L FeSO(4) concentration, pH 2.81 with 22 g/L SS. Further, the effect of ferro-sonication pre-treatment on biodegradation of WWS was also studied. It was observed that ultrasonication time had significant effect and the higher biodegradation (32.48%) was observed at 180 min ultrasonication time. 相似文献
24.
Regulation of the sterol-synthesizing mevalonate pathway occurs in part through feedback-regulated endoplasmic reticulum degradation of 3-hydroxy-3-methylglutaryl-CoA reductase (HMG-R). In yeast, the Hmg2p isozyme of HMG-R is regulated in this manner. We have tested the involvement of ubiquitination in the regulated degradation of Hmg2p, by using both genetic and direct biochemical approaches. Hmg2p degradation required the UBC7 gene, and Hmg2p protein was directly ubiquitinated. Hmg2p ubiquitination was dependent on UBC7 and was specific for the degraded yeast Hmg2p isozyme. Furthermore, Hmg2p ubiquitination was regulated by the mevalonate pathway in a manner consistent with regulation of Hmg2p stability. Thus, regulated ubiquitination appeared to be the mechanism by which Hmg2p stability is controlled in yeast. Finally, our data indicated that the feedback signal controlling Hmg2p ubiquitination and degradation was derived from farnesyl diphosphate, and thus implied conservation of an HMG-R degradation signal between yeast and mammals. 相似文献
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Embryoscopic diagnosis of conjoined twins presenting with a missed abortion has never been reported. The morphological and pathological examinations, and the exact time of death in the conceptus of a missed abortion are seldom clearly delineated. The newly developed field of embryoscopy has created a new frontier in early embryonic/fetal visualization and is able to confirm the sonographic diagnosis. In this report, we used a transcervical endoscope to verify conjoined twins (thoraco-omphalopagus) in a 10-week missed abortion. Based on the size and the external features of the dead embryo, which exhibited developmental arrest at nine weeks and three days of menstrual age, we estimated that the embryo had died four days before examination. The whole procedure proceeded smoothly without any immediate complications. 相似文献
28.
Suprachiasmatic nucleus organization 总被引:1,自引:0,他引:1
OBJECTIVE: To assess the effect of a combined exercise and motivation program on the compliance and level of disability of patients with chronic and recurrent low back pain. DESIGN: A double-blind prospective randomized controlled trial. SETTING: Physical therapy outpatient department, tertiary care. PATIENTS: Ninety-three low back pain patients were randomly assigned to either a standard exercise program (n = 49) or a combined exercise and motivation program (n = 44). INTERVENTIONS: Patients were prescribed 10 physical therapy sessions and were advised to continue exercising after treatment termination. The motivation program consisted of five compliance-enhancing interventions. Follow-up assessments were performed at 3 1/2 weeks, 4 months, and 12 months. MAIN OUTCOME MEASURES: Disability (low back outcome score), pain intensity, physical impairment (modified Waddell score, fingertip-to-floor distance, abdominal muscle strength), working ability, motivation, and compliance. RESULTS: The patients in the motivation group were significantly more likely to attend their exercise therapy appointments (p = .0005). Four and 12 months after study entry there was a significant difference in favor of the motivation group with regard to the disability score (p = .004) and pain intensity (p < or = .026). At 4 months, there was a significant advantage for the motivation group in the fingertip-to-floor distance (p = .01) and in abdominal muscle strength (p = .018). No significant differences were found in motivation scores, self-reported compliance with long-term exercise, and modified Waddell score. In terms of working ability, there was a trend favoring the combined exercise and motivation program. CONCLUSION: The combined exercise and motivation program increased the rate of attendance at scheduled physical therapy sessions, ie, short-term compliance, and reduced disability and pain levels by the 12-month follow-up. However, there was no difference between the motivation and control groups with regard to long-term exercise compliance. 相似文献
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JJ Worthington MH Pollack MW Otto RY McLean G Moroz JF Rosenbaum 《Canadian Metallurgical Quarterly》1998,34(2):199-205
OBJECTIVE: To assess the effect of the relief of obstruction on the ultimate function of the affected renal unit in urinary tuberculosis, and to identify predictors of functional recoverability. PATIENTS AND METHODS: Of a total of 82 patients with urinary tuberculosis presenting over 7 years, 38 with evidence of upper tract obstruction were analysed. All patients were assessed with pre-operative excretory urography, urinary mycobacterial cultures and serum chemistry. Patients with subnormally functioning kidneys were assessed with baseline renal scans. Preliminary intervention in the form of JJ stenting or percutaneous nephrostomy (PCN) was carried out in patients with reasonable renal function. Function was reassessed after 4 weeks to detect evidence of improvement and factors which could affect the outcome were determined. RESULTS: Thirty-eight patients had documented upper tract obstruction, of whom six had bilateral obstruction (total of 44 renal units). Ten renal units were not functioning at presentation, with a mean (SD) glomerular filtration rate (GFR) of 3.0 (5.73) mL/min, and no preliminary intervention was performed. In the remaining 34, preliminary intervention was carried out before definitive surgery (JJ stenting in 14, PCN in 15 and PCN followed by antegrade JJ stenting in five); 21 of these renal units were salvaged but 13 were lost despite overcoming the obstruction. Three of the 13 units deteriorated from having acceptable pre-treatment GFRs to becoming non-functional. Good renal cortical thickness, a low grade of renal involvement (Semb 1 or 2), the presence of more distal disease in the form of ureteric stricture and a GFR of > 15 mL/min were good predictors of renal recovery after diversion. CONCLUSIONS: The loss of some renal units seems inevitable in patients with urinary tuberculosis, despite advances in chemotherapy. Having pre-operative predictors of renal recovery may ensure optimal patient selection, thereby reducing the number of procedures and economic burden on the patient who does not require intervention. 相似文献